[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues...[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.展开更多
The Chinese medicine revitalization plan represented by Zhuang and Yao ethnic medicine has been incorporated into China’s and Guangxi’s overall economic and social development plans,reflecting that The Zhuang and Ya...The Chinese medicine revitalization plan represented by Zhuang and Yao ethnic medicine has been incorporated into China’s and Guangxi’s overall economic and social development plans,reflecting that The Zhuang and Yao ethnic medicine industry is an important part of China’s ethnic medicine,and it is also the representative ethnic medicine industry in Guangxi.In this paper,we investigated the development of Zhuang and Yao ethnic medicine industry and its development status by consulting literature,documents and related materials and visiting relevant departments,systematically analyzed the advantages and disadvantages of the development of Guangxi Zhuang and Yao ethnic medicine industry,and put forward feasible suggestions,aiming to accelerate the healthy development of Guangxi Zhuang and Yao ethnic medicine industry and provide effective data and decision-making basis for China to formulate relevant policies.展开更多
Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained promine...Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis efficiency.Recently,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault diagnosis.However,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative model.This complexity results in high computational costs and limited industrial applicability.To tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault diagnosis.First,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration signals.Then,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global perspective.Finally,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and Transformer.This study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.展开更多
[Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-l...[Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-layer identification characteristics.[Results]D.loddigesi has obvious plant morphology,characters,microscopic structure and thin-layer identification characteristics.The stem of Xiaohuangcao is slender and cylindrical,and the surface is golden yellow;and the fiber bundles outside the vascular bundles are crescent-shaped or semi-circular in the stem transection.For the powder,crystal fiber can be observed;the vascular bundles are embedded with siliceous block cells;and there are more starch grains.In the thin layer chromatography,petroleum ether-ethyl acetate-butanone-glacial acetic acid (8.5∶ 3.5∶ 1.5∶ 5 d) was used as a developing solvent,and 10% sulfuric acid ethanol solution was used as a color developing agent.[Conclusions]The research results provide reference for the application of the medicinal material and the formulation of its related quality standards.展开更多
Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerati...Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and active.Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool.Active adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits.This review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis.Furthermore,we discuss the physiological significance and underlying advantages of these diffe rences.Due to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.展开更多
This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1...This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1)Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26%and 30%,respectively,of the total samples,with primary hydrochemical type identified as HCO_(3)-Na.The karst and sand areas exhibit relatively high groundwater quality,serving as preferred sources for water supply.It is recommended that local governments fully harness groundwater in these areas;(2)groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin,which represents the drainage zone of groundwater;(3)arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources;(4)the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks,which are more serious to kids compared to adults.This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.展开更多
The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the tropics.We review the nature of this tran...The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the tropics.We review the nature of this transition and hypothesize the physical,ultimately climatic,factors thatmay maintain it,with a special focus on how the increasing instability and warming of climates will affect these forests.A primary climatic mediator of the transition is proposed,thereby offering a testable hypothesis for the climateeforest transition relationship.What is known of this transition is summarized in context of the primary climatic mediators of elevational zonation of forest formations in equatorial Asia to the tree line,in the Himalaya at the India-Indo-Burma northern tropical margin,and as both elevational and latitudinal zonation in southern China.Consequent secondary edaphic and other physical changes are described for the Himalaya,and hypothesized for southern China.The forest ecotones are seen to be primarily defined by tree floristic change,on which account changes in structure and physiognomy are determined.The montane tropical-subtropical transition in the Himalaya is narrowand observed to correlate with an as yet ill-defined frost line.A distinct tropical-subtropical transition forest is recognized in the southwest Chinamountains.There is a total change in canopy species at the Himalayan ecotone,but subcanopy tropical species persist along an elevational decline of c.400 m.The latitudinal transition in South China is analogous,but here the tropical subcanopy component extends north over ten degrees latitude,albeit in decline.The tropical-subtropical transition is uniquely clear in East Asia because here alone a tropical wet summer-dry winter monsoon extends to 35north latitude,encompassing the subtropical evergreen forest,whereas subtropical evergreen forests elsewhere exist under drier temperate summer climate regimes.展开更多
Varicella zoster virus(VZV) is the causative agent of varicella(chicken pox) and herpes zoster(shingles). After primary infection, the virus remains latent in sensory ganglia, and reactivates upon weakening of the cel...Varicella zoster virus(VZV) is the causative agent of varicella(chicken pox) and herpes zoster(shingles). After primary infection, the virus remains latent in sensory ganglia, and reactivates upon weakening of the cellular immune system due to various conditions, erupting from sensory neurons and infecting the corresponding skin tissue. The current varicella vaccine(v-Oka) is highly attenuated in the skin, yet retains its neurovirulence and may reactivate and damage sensory neurons. The reactivation is sometimes associated with postherpetic neuralgia(PHN), a severe pain along the affected sensory nerves that can linger for years, even after the herpetic rash resolves. In addition to the older population that develops a secondary infection resulting in herpes zoster, childhood breakthrough herpes zoster affects a small population of vaccinated children. There is a great need for a neuro-attenuated vaccine that would prevent not only the varicella manifestation, but, more importantly, any establishment of latency, and therefore herpes zoster. The development of a genetically-defined live-attenuated VZV vaccine that prevents neuronal and latent infection, in addition to primary varicella, is imperative for eventual eradication of VZV, and, if fully understood, has vast implications for many related herpesviruses and other viruses with similar pathogenic mechanisms.展开更多
The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous,island-like,distribution.It is diverse,rich in endemic species,and likely to be sensitive...The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous,island-like,distribution.It is diverse,rich in endemic species,and likely to be sensitive to climate change.Six 1-ha sampling plots were established across the main distribution area of the upper montane evergreen broad-leaved forest in Yunnan.All trees with d.b.h.>1 cm in each plot were identified.Patterns of seed plant distributions were quantified at the specific,generic and family levels.The forests are dominated by the families Fagaceae,Lauraceae,Theaceae and Magnoliaceae,but are very diverse with only a few species shared between sites.Floristic similarities at the family and generic level were high,but they were low at the specific level,with species complementarity between plots.Diversity varied greatly among sites,with greater species richness and more rare species in western Yunnan than central Yunnan.The flora is dominated by tropical biogeographical elements,mainly the pantropic and the tropical Asian distributions at the family and genus levels.In contrast,at the species level,the flora is dominated by the southwest or the southeast China distributions,including Yunnan endemics.This suggests that the flora of the upper montane forest in Yunnan could have a tropical floristic origin,and has adapted to cooler temperatures with the uplift of the Himalayas.Due to great sensitivity to climate,high endemism and species complementarity,as well as the discontinuous,island-like,distribution patterns of the upper montane forest in Yunnan,the regional conservation of the forest is especially needed.展开更多
Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential b...Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential biomarker to diagnose tumor,evaluate efficacy,and determine patient prognosis.TST001 is a recombinant humanized CLDN18.2 antibody that selectively binds to the extracellular loop of human Claudin18.2.In this study,we constructed a solid target radionuclide zirconium-^(89)(^(89)Zr)labled-TST001 to detect the expression of in the human stomach cancer BGC823CLDN18.2 cell lines.The[^(89)Zr]Zr-desferrioxamine(DFO)-TST001 showed high radiochemical purity(RCP,>99%)and specific activity(24.15±1.34 GBq/mmol),and was stable in 5%human serum albumin,and phosphate buffer saline(>85%RCP at 96 h).The EC_(50) values of TST001 and DFO-TST001 were as high as 0.413±0.055 and 0.361±0.058 nM(P>0.05),respectively.The radiotracer had a significantly higher average standard uptake values in CLDN18.2-positive tumors than in CLDN18.2-negative tumors(1.11±0.02 vs.0.49±0.03,P=0.0016)2 days post injection(p.i.).BGC823CLDN18.2 mice models showed high tumor/muscle ratios 96 h p.i.with[^(89)Zr]Zr-DFO-TST001 was much higher than those of the other imaging groups.Immunohistochemistry results showed that BGC823CLDN18.2 tumors were highly positive(+++)for CLDN18.2,while those in the BGC823 group did not express CLDN18.2().The results of ex vivo biodistribution studies showed that there was a higher distribution in the BGC823CLDN18.2 tumor bearing mice(2.05±0.16%ID/g)than BGC823 mice(0.69±0.02%ID/g)and blocking group(0.72±0.02%ID/g).A dosimetry estimation study showed that the effective dose of[^(89)Zr]Zr-DFO-TST001 was 0.0705 mSv/MBq,which is within the range of acceptable doses for nuclear medicine research.Taken together,these results suggest that Good Manufacturing Practices produced by this immuno-positron emission tomography probe can detect CLDN18.2-overexpressing tumors.展开更多
To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-T...To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as follows.First,the average microplastic abundance in surface water of the independent rivers and the whole area is 247−2686 items/m^(3) and 856 items/m^(3),respectively.The average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0−933 items/m^(2) and 362 items/m^(2),respectively.Meanwhile,the degree of microplastic pollution in river sediments is higher than that in lake sediments,and the rivers suffering from microplastic pollution mainly include the Brahmaputra River,Tongtian River,and Nujiang River.Second,compared with the microplastic pollution in other areas of the world,the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human activities.Finally,this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment.展开更多
The study of frictional properties of human skin is important for medical research, skin care products and textile exploi- tation. In order to investigate the influence of normal load and sliding speed on the friction...The study of frictional properties of human skin is important for medical research, skin care products and textile exploi- tation. In order to investigate the influence of normal load and sliding speed on the frictional properties of skin and its possible mechanism, tests were carded out on a multi-specimen friction tester. When the normal load increases from 0.1 N to 0.9 N, normal displacement and the friction coefficient of skin increase. The friction coefficient is dependent on the load, indicating that both adhesion and deformation contribute to the friction behaviour. The deformation friction was interpreted using the plough model of friction. When sliding speed increases from 0.5 mm·s^-1 to 4 mm·s^-1, the friction coefficient increases and ＂stick-slip＂ phenomena increase, indicating that hysteretic friction contributes to the friction. The hysteretic friction was in- terpreted using schematic of energy translation during the rigid spherical probe sliding on the soft skin surface, which provides an explanation for the influence of the sliding speed on the frictional characteristics of the skin.展开更多
In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper...In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during winter.The woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest savanna-like.However,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical south.The structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and Indo-Burma.Furthermore,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed tropical.We originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and Indo-Burma.The sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese range.The tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern China;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the Pliocene.The exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation.展开更多
Background:Experimental animals are used to study physiological phenomena,pathological mechanisms,and disease prevention.The gut microbiome is known as a potential confounding factor for inconsistent data from preclin...Background:Experimental animals are used to study physiological phenomena,pathological mechanisms,and disease prevention.The gut microbiome is known as a potential confounding factor for inconsistent data from preclinical studies.Although many gut microbiome studies have been conducted in recent decades,few have focused on gut microbiota fluctuation among representative mouse strains.Methods:A range of frequently used mouse strains were selected from 34 isolation packages representing disease-related animal(DRA),immunity defect animal(IDA),or gene-editing animal(GEA)from the BALB/c and C57BL/6J backgrounds together with normal mice,and their microbial genomic DNA were isolated from mouse feces to sequence for the exploration of gut microbiota.Results:Mouse background strain,classification,introduced source,introduced year,and reproduction type significantly affected the gut microbiota structure(p<0.001 for all parameters),with background strain contributing the greatest influence(R^(2)=0.237).In normal groups,distinct gut microbiota types existed in different mouse strains.Sixty-four core operational taxonomic units were obtained from normal mice,and 12 belonged to Lactobacillus.Interestingly,the gut microbiota in C57BL/6J was more stable than that in BALB/c mice.Furthermore,the gut microbiota in the IDA,GEA,and DRA groups significantly differed from that in normal groups(p<0.001 for all).Compared with the normal group,there was a significantly higher Chao 1 and Shannon index(p<0.001 for all)in the IDA,GEA,and DRA groups.Markedly changed classes occurred with Firmicutes and Bacteroidetes.The abundances of Helicobacter,Blautia,Enterobacter,Bacillus,Clostridioides,Paenibacillus,and Clostridiales all significantly decreased in the IDA,GEA,and DRA groups,whereas those of Saccharimonas,Rikenella,and Odoribacter all significantly increased.展开更多
Herpesviruses are a prominent cause of human viral disease, second only to the cold and influenza viruses. Most herpesvirus infections are mild or asymptomatic. However, when the virus invades the eye, a number of pat...Herpesviruses are a prominent cause of human viral disease, second only to the cold and influenza viruses. Most herpesvirus infections are mild or asymptomatic. However, when the virus invades the eye, a number of pathologies can develop and its associated sequelae have become a considerable source of ocular morbidity. The most common culprits of herpetic eye disease are the herpes simplex virus(HSV), varicella zoster virus(VZV), and cytomegalovirus(CMV). While primary infection can produce ocular disease, the most destructive manifestations tend to arise from recurrent infection. These recurrent infections can wreck devastating effects and lead to irreversible vision loss accompanied by a decreased quality of life, increased healthcare usage, and significant cost burden. Unfortunately, no method currently exists to eradicate herpesviruses from the body after infection. Treatment and management of herpes-related eye conditions continue to revolve around antiviral drugs, although corticosteroids, interferons, and other newer therapies may also be appropriate depending on the disease presentation. Ultimately, the advent of effective vaccines will be crucial to preventing herpesvirus diseases altogether and cutting the incidence of ocular complications.展开更多
[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As...[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.展开更多
This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the followi...This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.展开更多
基金Development of Huotanmu Capsules,a New Zhuang Ethnic Medicine for the Treatment of Hepatitis B(20183046-1)Collaborative Innovation Center of Zhuang and Yao Ethnic Medicine(GJKY[2013]20)+2 种基金Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicines(GKJZ[2014]32)Guangxi Key Discipline:Zhuang Pharmacology(GJKY[2013]16)First-class Discipline in Guangxi of Traditional Chinese Pharmacology(Direction of Ethnic Medicine)(GJKY[2018]12).
文摘[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.
基金Supported by Guangxi Zhuang Autonomous Region Philosophy and Social Science Planning Research Project"Guangxi Zhuang and Yao Ethnic Medicine Industry Development Research"(20BMZ005)Collaborative Innovation Center of Zhuang and Yao Ethnic Medicine[2013]No.20+3 种基金Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicine[2014]No.32Guangxi Engineering Research Center of Ethnic Medicine Resources and Application(Guifa Gai High Technology Letter[2020]No.2605)Guangxi Key Discipline:Zhuang Ethnic Pharmacognosy(GZXK-Z-20-64)The Eighth Batch of Guangxi Specially-employed Expert Projects(Study on Quality Standard of Zhuang and Yao Ethnic Medicine,GRCTZ[2019]13)。
文摘The Chinese medicine revitalization plan represented by Zhuang and Yao ethnic medicine has been incorporated into China’s and Guangxi’s overall economic and social development plans,reflecting that The Zhuang and Yao ethnic medicine industry is an important part of China’s ethnic medicine,and it is also the representative ethnic medicine industry in Guangxi.In this paper,we investigated the development of Zhuang and Yao ethnic medicine industry and its development status by consulting literature,documents and related materials and visiting relevant departments,systematically analyzed the advantages and disadvantages of the development of Guangxi Zhuang and Yao ethnic medicine industry,and put forward feasible suggestions,aiming to accelerate the healthy development of Guangxi Zhuang and Yao ethnic medicine industry and provide effective data and decision-making basis for China to formulate relevant policies.
基金supported by the National Natural Science Foundation of China(No.52277055).
文摘Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis efficiency.Recently,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault diagnosis.However,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative model.This complexity results in high computational costs and limited industrial applicability.To tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault diagnosis.First,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration signals.Then,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global perspective.Finally,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and Transformer.This study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.
基金Supported by Guangxi"2011 Collaborative Innovation Center"-Zhuang Yao Medicine Collaborative Innovation Center Project(GJKY[2013]20)Guangxi Key Laboratory of Zhuang Yao Medicine(GKJZ[2014]32)+7 种基金Guangxi Key Discipline:Zhuang Pharmacy(GJKY[2013]16)Bagui Scholars ProjectNational Natural Science Foundation of China(81460587)Nanning Science and Technology Bureau Project(20183046-1)Project of Guangxi Association for Science and TechnologyThe Fourth National General Survey of Chinese Medicine Resources(Guangxi)Pilot Survey Project(GXZYZYPC-2)Guangxi Marine Drug Resources Survey-Qinzhou City(GXZYZYPC13-7-2)Guangxi First-class Discipline:Chinese Pharmacy(0501802803)
文摘[Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-layer identification characteristics.[Results]D.loddigesi has obvious plant morphology,characters,microscopic structure and thin-layer identification characteristics.The stem of Xiaohuangcao is slender and cylindrical,and the surface is golden yellow;and the fiber bundles outside the vascular bundles are crescent-shaped or semi-circular in the stem transection.For the powder,crystal fiber can be observed;the vascular bundles are embedded with siliceous block cells;and there are more starch grains.In the thin layer chromatography,petroleum ether-ethyl acetate-butanone-glacial acetic acid (8.5∶ 3.5∶ 1.5∶ 5 d) was used as a developing solvent,and 10% sulfuric acid ethanol solution was used as a color developing agent.[Conclusions]The research results provide reference for the application of the medicinal material and the formulation of its related quality standards.
基金supported by the National Natural Science Foundation of China,No.82171336(to XX)。
文摘Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and active.Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool.Active adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits.This review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis.Furthermore,we discuss the physiological significance and underlying advantages of these diffe rences.Due to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.
基金funded by the ministry-province cooperation-based pilot project entitled A Technological System for Ecological Remediation Evaluation of Open-Pit Mines initiated by the Ministry of Natural Resources in 2023(2023-03)survey projects of the Land and Resources Investigation Program([2023]06-03-04,1212010634713)a key R&D projects of Shaanxi Province in 2023(2023ZDLSF-63)。
文摘This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1)Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26%and 30%,respectively,of the total samples,with primary hydrochemical type identified as HCO_(3)-Na.The karst and sand areas exhibit relatively high groundwater quality,serving as preferred sources for water supply.It is recommended that local governments fully harness groundwater in these areas;(2)groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin,which represents the drainage zone of groundwater;(3)arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources;(4)the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks,which are more serious to kids compared to adults.This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.
基金The National Natural Science Foundation of China(41471051,31970223)。
文摘The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the tropics.We review the nature of this transition and hypothesize the physical,ultimately climatic,factors thatmay maintain it,with a special focus on how the increasing instability and warming of climates will affect these forests.A primary climatic mediator of the transition is proposed,thereby offering a testable hypothesis for the climateeforest transition relationship.What is known of this transition is summarized in context of the primary climatic mediators of elevational zonation of forest formations in equatorial Asia to the tree line,in the Himalaya at the India-Indo-Burma northern tropical margin,and as both elevational and latitudinal zonation in southern China.Consequent secondary edaphic and other physical changes are described for the Himalaya,and hypothesized for southern China.The forest ecotones are seen to be primarily defined by tree floristic change,on which account changes in structure and physiognomy are determined.The montane tropical-subtropical transition in the Himalaya is narrowand observed to correlate with an as yet ill-defined frost line.A distinct tropical-subtropical transition forest is recognized in the southwest Chinamountains.There is a total change in canopy species at the Himalayan ecotone,but subcanopy tropical species persist along an elevational decline of c.400 m.The latitudinal transition in South China is analogous,but here the tropical subcanopy component extends north over ten degrees latitude,albeit in decline.The tropical-subtropical transition is uniquely clear in East Asia because here alone a tropical wet summer-dry winter monsoon extends to 35north latitude,encompassing the subtropical evergreen forest,whereas subtropical evergreen forests elsewhere exist under drier temperate summer climate regimes.
文摘Varicella zoster virus(VZV) is the causative agent of varicella(chicken pox) and herpes zoster(shingles). After primary infection, the virus remains latent in sensory ganglia, and reactivates upon weakening of the cellular immune system due to various conditions, erupting from sensory neurons and infecting the corresponding skin tissue. The current varicella vaccine(v-Oka) is highly attenuated in the skin, yet retains its neurovirulence and may reactivate and damage sensory neurons. The reactivation is sometimes associated with postherpetic neuralgia(PHN), a severe pain along the affected sensory nerves that can linger for years, even after the herpetic rash resolves. In addition to the older population that develops a secondary infection resulting in herpes zoster, childhood breakthrough herpes zoster affects a small population of vaccinated children. There is a great need for a neuro-attenuated vaccine that would prevent not only the varicella manifestation, but, more importantly, any establishment of latency, and therefore herpes zoster. The development of a genetically-defined live-attenuated VZV vaccine that prevents neuronal and latent infection, in addition to primary varicella, is imperative for eventual eradication of VZV, and, if fully understood, has vast implications for many related herpesviruses and other viruses with similar pathogenic mechanisms.
基金supported by the National Natural Science Foundation of China,No.41471051,41071040,31170195
文摘The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous,island-like,distribution.It is diverse,rich in endemic species,and likely to be sensitive to climate change.Six 1-ha sampling plots were established across the main distribution area of the upper montane evergreen broad-leaved forest in Yunnan.All trees with d.b.h.>1 cm in each plot were identified.Patterns of seed plant distributions were quantified at the specific,generic and family levels.The forests are dominated by the families Fagaceae,Lauraceae,Theaceae and Magnoliaceae,but are very diverse with only a few species shared between sites.Floristic similarities at the family and generic level were high,but they were low at the specific level,with species complementarity between plots.Diversity varied greatly among sites,with greater species richness and more rare species in western Yunnan than central Yunnan.The flora is dominated by tropical biogeographical elements,mainly the pantropic and the tropical Asian distributions at the family and genus levels.In contrast,at the species level,the flora is dominated by the southwest or the southeast China distributions,including Yunnan endemics.This suggests that the flora of the upper montane forest in Yunnan could have a tropical floristic origin,and has adapted to cooler temperatures with the uplift of the Himalayas.Due to great sensitivity to climate,high endemism and species complementarity,as well as the discontinuous,island-like,distribution patterns of the upper montane forest in Yunnan,the regional conservation of the forest is especially needed.
基金The research was funded by the National Natural Science Foundation of China(Grant Nos.:82171973,82171980,and 82102092)Beijing Millions of Talent Projects A Level Funding(Grant No.:2019A38)+2 种基金The study was also supported by Beijing Hospitals Authority Dengfeng Project(Grant No.:DFL20191102)the Pilot Project(4th Round)to Reform Public Development of Beijing Municipal Medical Research Institute(20211)the Third Foster Plan in 2019“Molecular Imaging Probe Preparation and Characterization of Key Technologies and Equipment”for the Development of Key Technologies and Equipment in Major Science and Technology Infrastructure in Shenzhen,China.
文摘Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential biomarker to diagnose tumor,evaluate efficacy,and determine patient prognosis.TST001 is a recombinant humanized CLDN18.2 antibody that selectively binds to the extracellular loop of human Claudin18.2.In this study,we constructed a solid target radionuclide zirconium-^(89)(^(89)Zr)labled-TST001 to detect the expression of in the human stomach cancer BGC823CLDN18.2 cell lines.The[^(89)Zr]Zr-desferrioxamine(DFO)-TST001 showed high radiochemical purity(RCP,>99%)and specific activity(24.15±1.34 GBq/mmol),and was stable in 5%human serum albumin,and phosphate buffer saline(>85%RCP at 96 h).The EC_(50) values of TST001 and DFO-TST001 were as high as 0.413±0.055 and 0.361±0.058 nM(P>0.05),respectively.The radiotracer had a significantly higher average standard uptake values in CLDN18.2-positive tumors than in CLDN18.2-negative tumors(1.11±0.02 vs.0.49±0.03,P=0.0016)2 days post injection(p.i.).BGC823CLDN18.2 mice models showed high tumor/muscle ratios 96 h p.i.with[^(89)Zr]Zr-DFO-TST001 was much higher than those of the other imaging groups.Immunohistochemistry results showed that BGC823CLDN18.2 tumors were highly positive(+++)for CLDN18.2,while those in the BGC823 group did not express CLDN18.2().The results of ex vivo biodistribution studies showed that there was a higher distribution in the BGC823CLDN18.2 tumor bearing mice(2.05±0.16%ID/g)than BGC823 mice(0.69±0.02%ID/g)and blocking group(0.72±0.02%ID/g).A dosimetry estimation study showed that the effective dose of[^(89)Zr]Zr-DFO-TST001 was 0.0705 mSv/MBq,which is within the range of acceptable doses for nuclear medicine research.Taken together,these results suggest that Good Manufacturing Practices produced by this immuno-positron emission tomography probe can detect CLDN18.2-overexpressing tumors.
基金funded by the survey projects initiated by the Ministry of Natural Resources of the People’s Republic of China(DD20189220,1212010741003,1212011220224,and 121201011000150022)the Public Welfare Scientific Research Project launched by the Ministry of Natural Resources of the People’s Republic of China(201111020)+3 种基金the project of 2015 Natural Science Basic Research Plan of Shaanxi Province(2015JM4129)the project of 2016 Fundamental Research Funds for the Central Universities(open fund310829161128)the project of 2021 Fundamental Research Funds for the Central Universities(open fund).
文摘To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as follows.First,the average microplastic abundance in surface water of the independent rivers and the whole area is 247−2686 items/m^(3) and 856 items/m^(3),respectively.The average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0−933 items/m^(2) and 362 items/m^(2),respectively.Meanwhile,the degree of microplastic pollution in river sediments is higher than that in lake sediments,and the rivers suffering from microplastic pollution mainly include the Brahmaputra River,Tongtian River,and Nujiang River.Second,compared with the microplastic pollution in other areas of the world,the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human activities.Finally,this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment.
基金This work was supported by the National Natural Science Foundation of China(grant No.50475164 and 50535050)by the Science Foundation of China University of Mining and Technology(grant No.2005B034).
文摘The study of frictional properties of human skin is important for medical research, skin care products and textile exploi- tation. In order to investigate the influence of normal load and sliding speed on the frictional properties of skin and its possible mechanism, tests were carded out on a multi-specimen friction tester. When the normal load increases from 0.1 N to 0.9 N, normal displacement and the friction coefficient of skin increase. The friction coefficient is dependent on the load, indicating that both adhesion and deformation contribute to the friction behaviour. The deformation friction was interpreted using the plough model of friction. When sliding speed increases from 0.5 mm·s^-1 to 4 mm·s^-1, the friction coefficient increases and ＂stick-slip＂ phenomena increase, indicating that hysteretic friction contributes to the friction. The hysteretic friction was in- terpreted using schematic of energy translation during the rigid spherical probe sliding on the soft skin surface, which provides an explanation for the influence of the sliding speed on the frictional characteristics of the skin.
基金funded by The National Natural Science Foundation of China(41471051,31970223)the major project of Yunnan Science and Technology Department-Yunnan University joint fund(2018FY001(-002))“Yunnan Vegegraphy Research”.Fig.1 was made by Yang Jianbo from GIS Lab in Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences.
文摘In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during winter.The woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest savanna-like.However,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical south.The structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and Indo-Burma.Furthermore,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed tropical.We originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and Indo-Burma.The sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese range.The tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern China;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the Pliocene.The exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation.
基金National Key R&D Program of ChinaGrant/Award Number:2021YFF0703400+3 种基金the National Natural Science Foundation of ChinaGrant/Award Number:General Program,82070103CAMS Innovation Fund for Medical ScienceGrant/Award Number:CIFMS,2021-I2M-1-036,2021-I 2M-1-034。
文摘Background:Experimental animals are used to study physiological phenomena,pathological mechanisms,and disease prevention.The gut microbiome is known as a potential confounding factor for inconsistent data from preclinical studies.Although many gut microbiome studies have been conducted in recent decades,few have focused on gut microbiota fluctuation among representative mouse strains.Methods:A range of frequently used mouse strains were selected from 34 isolation packages representing disease-related animal(DRA),immunity defect animal(IDA),or gene-editing animal(GEA)from the BALB/c and C57BL/6J backgrounds together with normal mice,and their microbial genomic DNA were isolated from mouse feces to sequence for the exploration of gut microbiota.Results:Mouse background strain,classification,introduced source,introduced year,and reproduction type significantly affected the gut microbiota structure(p<0.001 for all parameters),with background strain contributing the greatest influence(R^(2)=0.237).In normal groups,distinct gut microbiota types existed in different mouse strains.Sixty-four core operational taxonomic units were obtained from normal mice,and 12 belonged to Lactobacillus.Interestingly,the gut microbiota in C57BL/6J was more stable than that in BALB/c mice.Furthermore,the gut microbiota in the IDA,GEA,and DRA groups significantly differed from that in normal groups(p<0.001 for all).Compared with the normal group,there was a significantly higher Chao 1 and Shannon index(p<0.001 for all)in the IDA,GEA,and DRA groups.Markedly changed classes occurred with Firmicutes and Bacteroidetes.The abundances of Helicobacter,Blautia,Enterobacter,Bacillus,Clostridioides,Paenibacillus,and Clostridiales all significantly decreased in the IDA,GEA,and DRA groups,whereas those of Saccharimonas,Rikenella,and Odoribacter all significantly increased.
文摘Herpesviruses are a prominent cause of human viral disease, second only to the cold and influenza viruses. Most herpesvirus infections are mild or asymptomatic. However, when the virus invades the eye, a number of pathologies can develop and its associated sequelae have become a considerable source of ocular morbidity. The most common culprits of herpetic eye disease are the herpes simplex virus(HSV), varicella zoster virus(VZV), and cytomegalovirus(CMV). While primary infection can produce ocular disease, the most destructive manifestations tend to arise from recurrent infection. These recurrent infections can wreck devastating effects and lead to irreversible vision loss accompanied by a decreased quality of life, increased healthcare usage, and significant cost burden. Unfortunately, no method currently exists to eradicate herpesviruses from the body after infection. Treatment and management of herpes-related eye conditions continue to revolve around antiviral drugs, although corticosteroids, interferons, and other newer therapies may also be appropriate depending on the disease presentation. Ultimately, the advent of effective vaccines will be crucial to preventing herpesvirus diseases altogether and cutting the incidence of ocular complications.
基金Supported by the Project of National Natural Science Foundation of China(81460587)Project for Improving Basic Research Ability of Middle Aged and Young Teachers in Colleges and Universities of Guangxi in 2019(2019KY0310)+4 种基金Doctoral Starting up Foundation of Guangxi University of Chinese Medicine in 2018(2018BS019)Program of Collaborative Innovation Center of Zhuang and Yao Medicine(Gui Jiao Ke Yan[2013]No 20)Program of Key Laboratory of Zhuang and Yao Medicine(Gui Ke Ji Zi[2014]No.32)Program of Key Discipline of Guangxi(Zhuang Medicine Discipline)(Gui Jiao Ke Yan[2013]No.16)Innovation Research Program of Postgraduates of Guangxi University of Chinese Medicine(YCSY20190038)
文摘[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.
基金This study was funded by the survey projects initiated by the China Geological Survey(DD20189220,DD20211317,and 1212010634713).
文摘This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.
