Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mit...Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mitten crabs.Chinese mitten crabs,water,and different types of crab feed were collected from four different lakes for Sr isotope analyses.The results showed that the Sr isotope compositions of the different parts from one single crab were consistent within error,indicating that any piece of a crab could be used to represent the Sr isotope characteristics of the whole crab.The Sr isotope compositions of Chinese mitten crabs from the same lake were consistent within the analytical error,and the values were similar to the Sr isotope composition of the water from the same lake.However,the Sr isotope compositions of water and crabs from different lakes are significantly different.Therefore,the Sr isotope compositions of Chinese mitten crabs are mainly controlled by lake water composition,while the impact of feed is limited.This study provides an effective method for tracing the geographic origins of Chinese mitten crabs.展开更多
The genus Sheathia consists of over 20 species primarily distributed in Asia,Europe,Oceania,North America,and Africa.However,the origin and evolution of this genus remain unclear.Two gametophyte stage specimens(SAS180...The genus Sheathia consists of over 20 species primarily distributed in Asia,Europe,Oceania,North America,and Africa.However,the origin and evolution of this genus remain unclear.Two gametophyte stage specimens(SAS18052 and SAS18523)and two“Chantransia”stage specimens(YTS19161 and YTS19017)were collected from Shanxi and Henan Provinces in China,respectively.Based on morphological data,isolates YTS19161 and YTS19017 were similar to Audouinella pygmaea,whereas the morphological characteristics of SAS18052 and SAS18523 were in good agreement with the circumscription description of S.longipedicellata.Molecular sequences of rbc L,COI-5P,and psb A were used to investigate the phylogenetic,evolutionary,and biogeographic origin of the genus Sheathia.The three molecular markers supported that the two gametophyte stage specimens belong to S.longipedicellata,while the isolates YTS19161 and YTS19017 were the“Chantransia”of S.longipedicellata.Ancestral area reconstruction and divergence time estimation speculated that Sheathia originated in North America,a portion of the Pangaea at approximately 328.07-184.73 million years ago(Ma).Our relaxed molecular clock analysis suggests that the Florideophyceae diverged approximately 741.04(894.36-631.70)Ma.The major divergences in this class involved the emergence of Nemaliophycidae[ca.662.01(779.83-580.51)Ma],and the split of orders Batrachospermales and Thoreales[ca.456.10(552.80-367.88)Ma].展开更多
Variability in vitamin A (VA) intake of pregnant women in Ngaoundere town according to geographic origin, socio-professional and demographic factors was studied. A total of 100 pregnant women attending ante natal visi...Variability in vitamin A (VA) intake of pregnant women in Ngaoundere town according to geographic origin, socio-professional and demographic factors was studied. A total of 100 pregnant women attending ante natal visits at the Regional Hospital in Ngaoundere were involved in the survey. A questionnaire was used to obtain information on geographic origin, socio-professional status, birth history, demographic and anthropometric factors. Dietary intake was assessed using 24-hour dietary recall. Meals potentially rich in VA consumed by these women were collected, their carotenoids contents quantified and VA activity determined by conversion. Results indicated that daily VA intake of these women varied significantly (p < 0.05) with geographic origin, level of education and age of pregnancy. VA intake of pregnant women of Northern origin (Adamawa, North and Far North Regions) was significantly (p < 0.05) lower (496 μg/day/woman) than that of women of Southern origin (588 μg/day/woman), although both were below the recommended intake of 800 μg/day/woman. The more educated a woman and the older her pregnancy, the higher her VA intake. VA consumption of pregnant women of Northern origin was significantly influenced by their age, whereas for pregnant women of Southern origin, BMI (Body Mass Index) equally had a significant influence on their VA intake. Socio-professional status, marital status and number of children did not significantly influence the daily VA intake of these women. Thus, a pregnant woman originating from the Northern part of the country and having no formal education, consumed less foods rich in carotenoids and therefore was more at risk for vitamin A deficiency.展开更多
bstract A chemometric study using pattern recognition technology was carried out to characterize the geographic origins of the brown planthopper, Nilaparvata lugens. The concentrations of 23 trace elements (Mn, Mo, C...bstract A chemometric study using pattern recognition technology was carried out to characterize the geographic origins of the brown planthopper, Nilaparvata lugens. The concentrations of 23 trace elements (Mn, Mo, Cd, Ce, V, Th, Cs, Be, T1, Fe, Nd, Pr, Se, Tm, Lu, Eu, Ho, Br, Dy, Gd, U, Sm and Er) in 53 samples from seven regions in southern China were determined using inductively coupled plasma mass spectrometry. The data obtained were successively evaluated using a multivariate statistical approach, namely, linear discriminant analysis, which allowed classification and discrimination of the N. lugens samples from Fuqing, Shaoguan, Hepu, Yongfu, Hengnan, Wan-an and Yongkang with high accuracy and a clear separation among the seven regions. The results show that pattern identification on the basis of trace elements in the bodies ofN. lugens is feasible for determining the geographic origins of individuals.展开更多
The determination of the geographical origin as well as the adulteration of natural products is a technical problem due to similar chemical composition between an adulterant and the original. It is assumed that tartar...The determination of the geographical origin as well as the adulteration of natural products is a technical problem due to similar chemical composition between an adulterant and the original. It is assumed that tartaric acid comes from natural sources, however there is no specific regulation for this claim. This paper describes the use of isotope mass spectrometry associated with chemometrics to classify different samples of tartaric acid. The results showed that the variables δ^13C, δ^18O and δ^2H allowed the discrimination of tartaric acid samples by geographical origin and production method. By using a combination of chemometfic analysis it was possible to confirm a notoriousseparation of the samples. Thus, this is a promising method to be applied in the quality control and authenticity of tartaric acid.展开更多
Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an imag...Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an image analysis. Molecular techniques employing 16S and 28S rDNA profiles generated by PCR-DGGE were used to detect the variation in microbial community (bacteria, fungi) of Pangasius fish from Viet Nam harvested in different aquaculture farms and during different seasons and Shea tree fruits from five different districts in Mali. The bacterial DNA profiles from Pangasius fish and the fungal DNA profile from Shea tree fruits were specific to each place of production and could be used as a biological bar code certifying the origin of fish and fruit. To follow the product during processing, the authors proposed to identify and validate some pertinent biological markers which come from the environment of the food to assure their traceability during international trade. It is new analytical method which permits to determine the origin of food or to follow them during international trade.展开更多
This investigation aimed to establish the geographical traceability of Malaysian rice by assessing the elemental composition in paddy soil.Multi-element determination in combination with a chemometric approach was app...This investigation aimed to establish the geographical traceability of Malaysian rice by assessing the elemental composition in paddy soil.Multi-element determination in combination with a chemometric approach was applied to evaluate the elemental concentrations of paddy soil from granaries cultivated with the same rice variety and to assess the relationship between elements in the soil and rice(SAR) system.A total of 29 elements(aluminum,arsenic,barium,bromine,calcium,chlorine,cobalt,chromium,cesium,europium,iron,gallium,hafnium,potassium,lanthanum,lutetium,magnesium,manganese,sodium,rubidium,antimony,scandium,samarium,thorium,titanium,uranium,vanadium,ytterbium and zinc) were successfully determined in paddy soil from Kedah,Selangor and Langkawi by neutron activation analysis.A significant difference(P < 0.05) between 18 elements in the soil samples was obtained.The chemometric approaches of principal component and linear discriminant analyses demonstrated clear discrimination and highly corrected classification(100%) of the soil samples.A high classification(98.1%) was also achieved by assessing 10 elements(aluminum,arsenic,bromine,chlorine,potassium,magnesium,manganese,sodium,rubidium and zinc),which similarly applied to rice geographical origin determination.Similar elements in SAR were also observed for differences in the pattern of correlation and bioaccumulation factor between the granaries.Furthermore,the generalized Procrustes analysis showed a 98% consensus between SAR and clear differences between the studied regions.The canonical correlation analysis demonstrated a significant correlation between the chemical profile of SAR(r~2 = 0.88,P < 0.001).Therefore,the current work model provides a reliable assessment to establish rice provenance.展开更多
Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermen...Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak aging.The fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel aromas.The concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak barrels.The concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting ones.The compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could not.The fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious.展开更多
[ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geogra...[ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geographical populations of R.dybowskii which naturally distribute in Changhai Mountain and Xiaoxing'an Mountain were measured. Measure results were variance analyzed and cluster analyzed. [Result] Variance analysis showed: the genetic branching among the Dongfanghong male population( belongs to Wandashan) and Xiaoxing'an Mountain male population and Changbai Mountain male population were significantly different (P〈0.05) ; the genetic branching between the Hebei female population (belongs to Xiaoxing'an Mountain) and Changbai Mountain female population was significantly different (P〈0.05 ). Cluster analysis showed : male R.dybowskii can be divided into three groups : the first group included Quanyang, Tianbei, Chaoyang and Ddkouqin, the second group included Tieli and Anshan, the third group included Dongfanghong; and the female R. dybowskii can be divided into three groups : the first group included Quanyang and Chaoyang, the second group included Tianbei and Dakouqin, the third group included Hebei. [Condusion] The paper deduced that the Sanjiang Plain was the geographical origin center ofR. dybowskii which radiated to Changbai Mountain and Xiaoxing'an Mountain along the adverse current of Songhua River basin, therefore, the current distribution pattern of R. dybowskii was formed.展开更多
OBJECTIVE:To evaluate the quality of Moyao(Myrrh)in the identification of the geographical origin and processing of the products.METHODS:Raw Moyao(Myrrh)and two kinds of Moyao(Myrrh)processed with vinegar from three c...OBJECTIVE:To evaluate the quality of Moyao(Myrrh)in the identification of the geographical origin and processing of the products.METHODS:Raw Moyao(Myrrh)and two kinds of Moyao(Myrrh)processed with vinegar from three countries were identified using near-infrared(NIR)spectroscopy combined with chemometric techniques.Principal component analysis(PCA)was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories.A classical chemometric algorithm(PLS-DA)and two machine learning algorithms[K-nearest neighbor(KNN)and support vector machine]were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh)samples,and their discriminative performance was evaluated.RESULTS:Based on the accuracy,precision,recall rate,and F1 value in each model,the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive results.In all of the chemometric analyses,the NIR spectrum of Moyao(Myrrh)preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins,and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the best.The best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 respectively.CONCLUSIONS:NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh)and can also provide a reference for evaluations of its quality and the clinical use.展开更多
Mentha haplocalyx(mint)is a significant traditional Chinese medicine(TCM)listed in the Catalogue of’Medicinal and Food Homology’,therefore,its geographical origins(GOs)are critical to the medicinal and food value.La...Mentha haplocalyx(mint)is a significant traditional Chinese medicine(TCM)listed in the Catalogue of’Medicinal and Food Homology’,therefore,its geographical origins(GOs)are critical to the medicinal and food value.Laser-induced breakdown spectroscopy(LIBS)is an advanced analytical technique for GOs certification,due to the fast multi-elemental analysis requiring minimal sample pretreatment.In this study,LIBS data of sampled mint from five GOs were investigated by LIBS coupled with multivariate statistical analyzes.The spectral data was analyzed by two chemometric algorithms,i.e.principal component analysis(PCA)and least squares support vector machines(LS-SVM).Specifically,the performance of LS-SVM with least kernel and radial basis function(RBF)kernel was explored in sensitivity and robustness tests.Both LS-SVM algorithms exhibited excellent performance of classification in sensitive test and good performance(a little inferior)in robustness test.Generally,LS-SVM with linear kernel equally outperformed LS-SVM based on RBF kernel.The result indicated the potential for future applications in herbs and food,especially for in situ GOs applications of TCM authenticity rapidly.展开更多
Near infrared spectroscopy(NIRS),coupled with principal component analysis and wavelength selection techniques,has been sed to develop a robust and reliable reduced-spectrum classifi-cation model for determining the g...Near infrared spectroscopy(NIRS),coupled with principal component analysis and wavelength selection techniques,has been sed to develop a robust and reliable reduced-spectrum classifi-cation model for determining the geographical origins of Nanfeng mandarins.The application of the changeable size moving window principal component analysis(CSMWPCA)provided a notably improved lassification model,with correct classification rates of 92.00%,100.00%,90.00%,100.00%,100.00%,100.00%and 100.00%for Fujian,Guangxi,Hunan,Baishe,Baofeng,Qiawan,Sanxi samples,respectively,as well as,a total dassification rate of 97.52%in the wavelength range from 1007 to 1296 nm.To test and apply the proposed method,the procedure was applied to the analysis of 59 samples in an independent test set.Good identification results(correct rate of 96.61%)were also received.The improvement achieved by the application of CSMWPCA method was particularly remarkable when taking the low complexities of the final model(290 variables)into account.The results of the study showed the great potential of NIRS as a fast,nondestructive and environmentally acceptable method for the rapid and reliable determination for geographical classifcation of Nanfeng mandarins.展开更多
Objective: This paper focused on the geographical discrimination of Cyclocarya paliurus tea for origin traceability based on multielement analysis by ICP-OES and chemometrics multivariate.Methods: In this study, eleve...Objective: This paper focused on the geographical discrimination of Cyclocarya paliurus tea for origin traceability based on multielement analysis by ICP-OES and chemometrics multivariate.Methods: In this study, eleven trace element concentrations were determined by ICP-OES and processed by multivariate statistical analysis.Results: Based on ANOVA, the mean concentrations of 10 elements except Co differed significantly among six origins. Pearson’s correlation analysis showed that 11 pairs of elements have a positive significant correlation and 12 pairs have a negative significant correlation. The geographical origins were effectively differentiated using the eleven elements combined with PCA. And the S-LDA model offered a 100%differentiation rate.Conclusion: The overall results suggested that the combination of multielement analysis by ICP-OES and chemometrics multivariate could trace the geographical origins of tea. And the paper can provide reference for quality control and quality evaluation of C. paliurus in the future.展开更多
Element profile was investigated for their use to trace the geographical origin of rice (Oryza sativa L.) samples. The concentrations of 13 elements (calcium (Ca), potassium (K), magnesium (Mg), phosphorus (...Element profile was investigated for their use to trace the geographical origin of rice (Oryza sativa L.) samples. The concentrations of 13 elements (calcium (Ca), potassium (K), magnesium (Mg), phosphorus (P), boron (B), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), arsenic (As), selenium (Se), molybdenum (Mo), and cadmium (Cd)) were determined in the rice samples by inductively coupled plasma optical emission and mass spectrometry. Most of the essential elements for human health in rice were within normal ranges except for Mo and Se. Mo concentrations were twice as high as those in rice from Vietnam and Spain. Meanwhile, Se concentrations were three times lower in the whole province compared to the Chinese average level of 0.088 mg/kg. About 12% of the rice samples failed the Chinese national food safety standard of 0.2 mg/kg for Cd. Combined with the multi-elemental profile in rice, the principal component analysis (PCA), discriminant function analysis (DFA) and Fibonacci index analysis (FIA) were applied to discriminate geographical origins of the samples. Results indicated that the FIA method could achieve a more effective geographical origin classification compared with PCA and DFA, due to its efficiency in making the grouping even when the elemental variability was so high that PCA and DFA showed little discriminatory power. Furthermore, some elements were identified as the most powerful indicators of geographical origin: Ca, Ni, Fe and Cd. This suggests that the newly established methodology of FIA based on the ionome profile can be applied to determine the geographical origin of rice.展开更多
The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong...The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong(GD),Guangxi(GX),Hainan(HA),Fujian(FJ),Shandong(SD),Sichuan(SC),Chongqing(CQ),and Henan(HN) provinces was high,while in Zhejiang(ZJ),Hubei(HB),Yunnan(YN),and Anhui(AH) provinces,it was low.Tea samples from GD,GX,HA,and FJ provinces were clustered in one group and separated from those from AH and HB provinces.Thus,carbon and nitrogen stable isotope ratio technology could discriminate teas from among some provinces of China,but not from among others.Better separation might be obtained with a combination of isotopic ratios and other indexes,such as elemental data and organic components.展开更多
Background:As the demand for traditional Chinese medicinal materials increases in China and even the world,there is an urgent need for an effective and simple identification technology to identify the origin and quali...Background:As the demand for traditional Chinese medicinal materials increases in China and even the world,there is an urgent need for an effective and simple identification technology to identify the origin and quality of the latter and ensure the safety of clinical medication.Mineral element analysis and isotope finger-printing are the two commonly used techniques in traditional origin identification.Both of these techniques require the use of stoichiometric methods in the identification process.Although they have high accuracy and sensitivity,they are expensive and inefficient.In addition,near-infrared spectroscopy is a fast,nondestructive,and widely used identification technique developed in recent years,but its identification results are susceptible to samples’states and environmental conditions,and its sensitivity is low.Hyperspectral imaging combines the advantages of imaging technology and optical technology,which can simultaneously access the image information and spectral information which reflect the external characteristics,internal physical structure,and chemical composition of the samples.Hyperspectral imaging is widely applied to agricultural product inspection,but research into its application in origin and quality identification of TCM materials is rare.Methods:In this study,the algorithm framework discriminative marginalized least squares regression(DMLSR)was used for feature extraction of frankincense hyperspectral data.The DMLSR with intraclass compactness graph and manifold regularization can efficiently learn the projective samples with higher separability and less redundant information than the original samples.Then,the discriminative collaborative representation with Tikhonov regularization(DCRT)was applied for classifying the geographical origin and level of frankincense.DCRT introduces the discriminant regularization term and incorporates SID,which is more sensitive to the spectrum as the measurement method and is more suitable for the frankincense spectral data compared with SVM.Results:For the origin classification task,samples of all levels from each origin were,respectively,selected for three-way classification.We used 10-fold cross-validation to select a model parameter in the experiment.When obtaining the optimal parameters,we randomly selected the training set and testing set,where the training set accounts for 70%and the training set for 30%.After repeating this random process 10 times,we obtained the final average classification accuracy,which is higher than 90%,and the standard deviation fluctuation is usually small.For the level classification task,samples of each level from three origins were separately selected for multiclassification.We randomly selected the training set and testing set from each origin.The level classification results of the three origins are good on D4350 data,and the classification accuracy of each level is basically above 80%.Conclusion:Experiments and analysis show that our algorithm framework has excellent classification performance,which is stable in origin classification and has potential for generalization.In addition,the experiments show that in our algorithm framework,different classification tasks need to combine different data sources to achieve better classification and recognition,as the origin classification task uses frankincense’s D3000 data,and level classification task uses frankincense’s D4350 data.展开更多
Place of origin has an important influence on walnut quality and commercial value,which results in the requirement of rapid geographical traceability method.Thus,a method for geographical origin identification of waln...Place of origin has an important influence on walnut quality and commercial value,which results in the requirement of rapid geographical traceability method.Thus,a method for geographical origin identification of walnuts on the basis of nutritional quality of walnuts from China was conducted.The concentrations of 43 phytochemical components were analyzed in walnut samples from five different walnut-producing regions of China.Based on 14 chemical markers selected by the Random Forest method from these phytochemical components,a new discriminant model for geographical origin was built,with the corresponding correct classification rate of 99.3%.In addition,the quantitative quality differences of walnuts from five regions were analyzed,with values of 0.17–1.43.Moreover,the top three chemical markers for the geographical origin discriminant analysis were Mo,V,and stearic acid,with contribution rates of 26.8%,18.9%,and 10.9%,respectively.This study provides a potentially viable method for application in food authentication.展开更多
The <span style="font-family:Verdana;">paper</span><span style="font-family:Verdana;"> presents the results of a study of salt tolerance in some different eco</span><span...The <span style="font-family:Verdana;">paper</span><span style="font-family:Verdana;"> presents the results of a study of salt tolerance in some different eco</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">geographical samples of the cotton germplasm collection of the Institute of Genetics and Experimental Biology of the Academy of Sciences of t</span><span style="font-family:Verdana;">he Republic of Uzbekistan. According to the results obtained, the studied samples were divided into several groups </span><span style="font-family:Verdana;">depending on their </span><span style="font-family:;" "=""><span style="font-family:Verdana;">salt tolerance. Salt tolerant and unstable samples were found in all studied ecological and geographical </span><span style="font-family:Verdana;">groups,</span><span style="font-family:Verdana;"> but differ</span></span><span style="font-family:Verdana;">ed</span><span style="font-family:Verdana;"> in the frequency of distribution.</span>展开更多
The United States was hard hit by the great influenza pandemic of 1918.The national policy of putting the war first,the unprecedented scale of military training,and the worldwide troop movements and engagement created...The United States was hard hit by the great influenza pandemic of 1918.The national policy of putting the war first,the unprecedented scale of military training,and the worldwide troop movements and engagement created the conditions for the spread of the pandemic and at the same time seriously weakened US preparedness.The unprecedented pandemic threw American society into extreme panic and spawned all kinds of hypotheses about the pandemic’s geographic origin.Some of the press turned scientifically“tracing the flu”into a succession of pejorative geopolitical exonyms,stigmatizing it as“Spanish flu,”“Russian flu,”“German poisoning,”“Chinese plague,”etc.The groundless ascription of a geographic origin to the influenza pandemic was questioned at the time by insightful American medical professionals and even by Chinese medical experts.In the aftermath of the pandemic,tracking its source became a professional issue of pure medical science,with the search for the pathogen of the pandemic becoming a priority.The discovery and genetic sequencing of the 1918 influenza virus by scientists in the US and other countries led to landmark advances in the discovery of the pathogen,so the importance of tracing it back to its place of origin has taken a back seat.Although evidence of the geographic origin of the 1918 influenza pandemic is not conclusive,medical science has developed enough to disprove the ridiculous“geographic tracking”in the US during the pandemic.展开更多
Reflection of ultraviolet (UV) light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, refle...Reflection of ultraviolet (UV) light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, reflect little UV light, while butterflies of the Asian subspecies, P. rapae crucivora, may reflect it strongly or at only intermediate levels. The geographic region where P. rapae originated remains to be determined, Moreover, it is not clear if females with wings that reflect little UV light are ancestral to females with wings that reflect UV strongly or vice versa. In the present study, we aimed to determine the geographic origin and ancestral UV pattern of cabbage butterflies through mitochondrial DNA (mtDNA) sequence analysis and amplified fragment length polymorphism (AFLP) analysis. The results of these investigations suggest that P. rapae is of European origin and that it has expanded its distribution eastward to Asia. It follows that the ancestral subspecies is the type with UV-absorbing wings. Lower nucleotide diversities and haplotype network patterns ofmtDNA derived from East Asian populations suggest that population expansion from Europe to East Asia probably occurred fairly recently and at a rapid rate.展开更多
基金financially supported by the National Key Research and Development Program of Chinathe project of Source Identification and Contamination Characteristics of Heavy Metals in Agricultural Land and Products (2016YFD0800300)by Natural Science Foundation of China (41721002)
文摘Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mitten crabs.Chinese mitten crabs,water,and different types of crab feed were collected from four different lakes for Sr isotope analyses.The results showed that the Sr isotope compositions of the different parts from one single crab were consistent within error,indicating that any piece of a crab could be used to represent the Sr isotope characteristics of the whole crab.The Sr isotope compositions of Chinese mitten crabs from the same lake were consistent within the analytical error,and the values were similar to the Sr isotope composition of the water from the same lake.However,the Sr isotope compositions of water and crabs from different lakes are significantly different.Therefore,the Sr isotope compositions of Chinese mitten crabs are mainly controlled by lake water composition,while the impact of feed is limited.This study provides an effective method for tracing the geographic origins of Chinese mitten crabs.
基金Supported by the National Natural Science Foundation of China(Nos.31670208,41871037,31800172)the Fund for Shanxi“1331 Project”。
文摘The genus Sheathia consists of over 20 species primarily distributed in Asia,Europe,Oceania,North America,and Africa.However,the origin and evolution of this genus remain unclear.Two gametophyte stage specimens(SAS18052 and SAS18523)and two“Chantransia”stage specimens(YTS19161 and YTS19017)were collected from Shanxi and Henan Provinces in China,respectively.Based on morphological data,isolates YTS19161 and YTS19017 were similar to Audouinella pygmaea,whereas the morphological characteristics of SAS18052 and SAS18523 were in good agreement with the circumscription description of S.longipedicellata.Molecular sequences of rbc L,COI-5P,and psb A were used to investigate the phylogenetic,evolutionary,and biogeographic origin of the genus Sheathia.The three molecular markers supported that the two gametophyte stage specimens belong to S.longipedicellata,while the isolates YTS19161 and YTS19017 were the“Chantransia”of S.longipedicellata.Ancestral area reconstruction and divergence time estimation speculated that Sheathia originated in North America,a portion of the Pangaea at approximately 328.07-184.73 million years ago(Ma).Our relaxed molecular clock analysis suggests that the Florideophyceae diverged approximately 741.04(894.36-631.70)Ma.The major divergences in this class involved the emergence of Nemaliophycidae[ca.662.01(779.83-580.51)Ma],and the split of orders Batrachospermales and Thoreales[ca.456.10(552.80-367.88)Ma].
文摘Variability in vitamin A (VA) intake of pregnant women in Ngaoundere town according to geographic origin, socio-professional and demographic factors was studied. A total of 100 pregnant women attending ante natal visits at the Regional Hospital in Ngaoundere were involved in the survey. A questionnaire was used to obtain information on geographic origin, socio-professional status, birth history, demographic and anthropometric factors. Dietary intake was assessed using 24-hour dietary recall. Meals potentially rich in VA consumed by these women were collected, their carotenoids contents quantified and VA activity determined by conversion. Results indicated that daily VA intake of these women varied significantly (p < 0.05) with geographic origin, level of education and age of pregnancy. VA intake of pregnant women of Northern origin (Adamawa, North and Far North Regions) was significantly (p < 0.05) lower (496 μg/day/woman) than that of women of Southern origin (588 μg/day/woman), although both were below the recommended intake of 800 μg/day/woman. The more educated a woman and the older her pregnancy, the higher her VA intake. VA consumption of pregnant women of Northern origin was significantly influenced by their age, whereas for pregnant women of Southern origin, BMI (Body Mass Index) equally had a significant influence on their VA intake. Socio-professional status, marital status and number of children did not significantly influence the daily VA intake of these women. Thus, a pregnant woman originating from the Northern part of the country and having no formal education, consumed less foods rich in carotenoids and therefore was more at risk for vitamin A deficiency.
文摘bstract A chemometric study using pattern recognition technology was carried out to characterize the geographic origins of the brown planthopper, Nilaparvata lugens. The concentrations of 23 trace elements (Mn, Mo, Cd, Ce, V, Th, Cs, Be, T1, Fe, Nd, Pr, Se, Tm, Lu, Eu, Ho, Br, Dy, Gd, U, Sm and Er) in 53 samples from seven regions in southern China were determined using inductively coupled plasma mass spectrometry. The data obtained were successively evaluated using a multivariate statistical approach, namely, linear discriminant analysis, which allowed classification and discrimination of the N. lugens samples from Fuqing, Shaoguan, Hepu, Yongfu, Hengnan, Wan-an and Yongkang with high accuracy and a clear separation among the seven regions. The results show that pattern identification on the basis of trace elements in the bodies ofN. lugens is feasible for determining the geographic origins of individuals.
文摘The determination of the geographical origin as well as the adulteration of natural products is a technical problem due to similar chemical composition between an adulterant and the original. It is assumed that tartaric acid comes from natural sources, however there is no specific regulation for this claim. This paper describes the use of isotope mass spectrometry associated with chemometrics to classify different samples of tartaric acid. The results showed that the variables δ^13C, δ^18O and δ^2H allowed the discrimination of tartaric acid samples by geographical origin and production method. By using a combination of chemometfic analysis it was possible to confirm a notoriousseparation of the samples. Thus, this is a promising method to be applied in the quality control and authenticity of tartaric acid.
文摘Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an image analysis. Molecular techniques employing 16S and 28S rDNA profiles generated by PCR-DGGE were used to detect the variation in microbial community (bacteria, fungi) of Pangasius fish from Viet Nam harvested in different aquaculture farms and during different seasons and Shea tree fruits from five different districts in Mali. The bacterial DNA profiles from Pangasius fish and the fungal DNA profile from Shea tree fruits were specific to each place of production and could be used as a biological bar code certifying the origin of fish and fruit. To follow the product during processing, the authors proposed to identify and validate some pertinent biological markers which come from the environment of the food to assure their traceability during international trade. It is new analytical method which permits to determine the origin of food or to follow them during international trade.
基金supported by the Universiti Kebangsaan Malaysia research grant(Grant No.GGP-2020-012)。
文摘This investigation aimed to establish the geographical traceability of Malaysian rice by assessing the elemental composition in paddy soil.Multi-element determination in combination with a chemometric approach was applied to evaluate the elemental concentrations of paddy soil from granaries cultivated with the same rice variety and to assess the relationship between elements in the soil and rice(SAR) system.A total of 29 elements(aluminum,arsenic,barium,bromine,calcium,chlorine,cobalt,chromium,cesium,europium,iron,gallium,hafnium,potassium,lanthanum,lutetium,magnesium,manganese,sodium,rubidium,antimony,scandium,samarium,thorium,titanium,uranium,vanadium,ytterbium and zinc) were successfully determined in paddy soil from Kedah,Selangor and Langkawi by neutron activation analysis.A significant difference(P < 0.05) between 18 elements in the soil samples was obtained.The chemometric approaches of principal component and linear discriminant analyses demonstrated clear discrimination and highly corrected classification(100%) of the soil samples.A high classification(98.1%) was also achieved by assessing 10 elements(aluminum,arsenic,bromine,chlorine,potassium,magnesium,manganese,sodium,rubidium and zinc),which similarly applied to rice geographical origin determination.Similar elements in SAR were also observed for differences in the pattern of correlation and bioaccumulation factor between the granaries.Furthermore,the generalized Procrustes analysis showed a 98% consensus between SAR and clear differences between the studied regions.The canonical correlation analysis demonstrated a significant correlation between the chemical profile of SAR(r~2 = 0.88,P < 0.001).Therefore,the current work model provides a reliable assessment to establish rice provenance.
基金the financial support received from The Key Project of R&D Program of Ningxia Hui Autonomous Region,China(2022BBF01003)China Agriculture Research System of MOF and MARA(CARS-29).
文摘Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak aging.The fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel aromas.The concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak barrels.The concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting ones.The compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could not.The fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious.
文摘[ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geographical populations of R.dybowskii which naturally distribute in Changhai Mountain and Xiaoxing'an Mountain were measured. Measure results were variance analyzed and cluster analyzed. [Result] Variance analysis showed: the genetic branching among the Dongfanghong male population( belongs to Wandashan) and Xiaoxing'an Mountain male population and Changbai Mountain male population were significantly different (P〈0.05) ; the genetic branching between the Hebei female population (belongs to Xiaoxing'an Mountain) and Changbai Mountain female population was significantly different (P〈0.05 ). Cluster analysis showed : male R.dybowskii can be divided into three groups : the first group included Quanyang, Tianbei, Chaoyang and Ddkouqin, the second group included Tieli and Anshan, the third group included Dongfanghong; and the female R. dybowskii can be divided into three groups : the first group included Quanyang and Chaoyang, the second group included Tianbei and Dakouqin, the third group included Hebei. [Condusion] The paper deduced that the Sanjiang Plain was the geographical origin center ofR. dybowskii which radiated to Changbai Mountain and Xiaoxing'an Mountain along the adverse current of Songhua River basin, therefore, the current distribution pattern of R. dybowskii was formed.
基金Jiangxi Provincial Administration of Traditional Chinese Medicine Key Research Laboratory on the Fundamentals of Chinese Medicine Evidence(Gan TCM Science and Education Word[2022]No.8-4)Jiangxi University of Chinese Medicine Science and Technology Innovation Team Development Program:Traditional Chinese Medicine Constitution-State Identification Health Management Research Team(No.CXTD22016)。
文摘OBJECTIVE:To evaluate the quality of Moyao(Myrrh)in the identification of the geographical origin and processing of the products.METHODS:Raw Moyao(Myrrh)and two kinds of Moyao(Myrrh)processed with vinegar from three countries were identified using near-infrared(NIR)spectroscopy combined with chemometric techniques.Principal component analysis(PCA)was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories.A classical chemometric algorithm(PLS-DA)and two machine learning algorithms[K-nearest neighbor(KNN)and support vector machine]were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh)samples,and their discriminative performance was evaluated.RESULTS:Based on the accuracy,precision,recall rate,and F1 value in each model,the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive results.In all of the chemometric analyses,the NIR spectrum of Moyao(Myrrh)preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins,and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the best.The best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 respectively.CONCLUSIONS:NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh)and can also provide a reference for evaluations of its quality and the clinical use.
基金supported by National Natural Science Foundation of China(Nos.81903796,81603396 and 31870338)the National Key Research and Development Program of China(No.2019YFC1711200)+2 种基金Major new drug innovation project of the ministry of science and technology(2018ZX09201011)Scientific and Technological Planning Projects of Colleges and Universities of Shandong Province(No.J18KA287)Binzhou Medical University Research Startup Fund Project(No.BY2016KYQD02)。
文摘Mentha haplocalyx(mint)is a significant traditional Chinese medicine(TCM)listed in the Catalogue of’Medicinal and Food Homology’,therefore,its geographical origins(GOs)are critical to the medicinal and food value.Laser-induced breakdown spectroscopy(LIBS)is an advanced analytical technique for GOs certification,due to the fast multi-elemental analysis requiring minimal sample pretreatment.In this study,LIBS data of sampled mint from five GOs were investigated by LIBS coupled with multivariate statistical analyzes.The spectral data was analyzed by two chemometric algorithms,i.e.principal component analysis(PCA)and least squares support vector machines(LS-SVM).Specifically,the performance of LS-SVM with least kernel and radial basis function(RBF)kernel was explored in sensitivity and robustness tests.Both LS-SVM algorithms exhibited excellent performance of classification in sensitive test and good performance(a little inferior)in robustness test.Generally,LS-SVM with linear kernel equally outperformed LS-SVM based on RBF kernel.The result indicated the potential for future applications in herbs and food,especially for in situ GOs applications of TCM authenticity rapidly.
基金supported by General Administration of Quality Supervision,Inspection and Quarantine of the People's Republic of China (2012IK169)National Natural Science Youth Foundation of China (21205053).
文摘Near infrared spectroscopy(NIRS),coupled with principal component analysis and wavelength selection techniques,has been sed to develop a robust and reliable reduced-spectrum classifi-cation model for determining the geographical origins of Nanfeng mandarins.The application of the changeable size moving window principal component analysis(CSMWPCA)provided a notably improved lassification model,with correct classification rates of 92.00%,100.00%,90.00%,100.00%,100.00%,100.00%and 100.00%for Fujian,Guangxi,Hunan,Baishe,Baofeng,Qiawan,Sanxi samples,respectively,as well as,a total dassification rate of 97.52%in the wavelength range from 1007 to 1296 nm.To test and apply the proposed method,the procedure was applied to the analysis of 59 samples in an independent test set.Good identification results(correct rate of 96.61%)were also received.The improvement achieved by the application of CSMWPCA method was particularly remarkable when taking the low complexities of the final model(290 variables)into account.The results of the study showed the great potential of NIRS as a fast,nondestructive and environmentally acceptable method for the rapid and reliable determination for geographical classifcation of Nanfeng mandarins.
基金supported by the National Natural Science Foundation of China(No.81360631)Project of the Key Research and Development Program for Jiangxi Province(No.20203BBGL73218)。
文摘Objective: This paper focused on the geographical discrimination of Cyclocarya paliurus tea for origin traceability based on multielement analysis by ICP-OES and chemometrics multivariate.Methods: In this study, eleven trace element concentrations were determined by ICP-OES and processed by multivariate statistical analysis.Results: Based on ANOVA, the mean concentrations of 10 elements except Co differed significantly among six origins. Pearson’s correlation analysis showed that 11 pairs of elements have a positive significant correlation and 12 pairs have a negative significant correlation. The geographical origins were effectively differentiated using the eleven elements combined with PCA. And the S-LDA model offered a 100%differentiation rate.Conclusion: The overall results suggested that the combination of multielement analysis by ICP-OES and chemometrics multivariate could trace the geographical origins of tea. And the paper can provide reference for quality control and quality evaluation of C. paliurus in the future.
基金supported by the Ministry of Science and Technology,China (No.2009DFB90120)
文摘Element profile was investigated for their use to trace the geographical origin of rice (Oryza sativa L.) samples. The concentrations of 13 elements (calcium (Ca), potassium (K), magnesium (Mg), phosphorus (P), boron (B), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), arsenic (As), selenium (Se), molybdenum (Mo), and cadmium (Cd)) were determined in the rice samples by inductively coupled plasma optical emission and mass spectrometry. Most of the essential elements for human health in rice were within normal ranges except for Mo and Se. Mo concentrations were twice as high as those in rice from Vietnam and Spain. Meanwhile, Se concentrations were three times lower in the whole province compared to the Chinese average level of 0.088 mg/kg. About 12% of the rice samples failed the Chinese national food safety standard of 0.2 mg/kg for Cd. Combined with the multi-elemental profile in rice, the principal component analysis (PCA), discriminant function analysis (DFA) and Fibonacci index analysis (FIA) were applied to discriminate geographical origins of the samples. Results indicated that the FIA method could achieve a more effective geographical origin classification compared with PCA and DFA, due to its efficiency in making the grouping even when the elemental variability was so high that PCA and DFA showed little discriminatory power. Furthermore, some elements were identified as the most powerful indicators of geographical origin: Ca, Ni, Fe and Cd. This suggests that the newly established methodology of FIA based on the ionome profile can be applied to determine the geographical origin of rice.
基金Project supported by the National Key Technologies R&D Program of China during the 11th Five-Year Plan Period (No. 2006BAK02A18)the Innovation Team of the Safety Standards and Testing Technology for Agricultural Products of Zhejiang Province,China(No. 2010R50028)
文摘The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio technology.The results showed that inter-provincial dispersion of teas in Guangdong(GD),Guangxi(GX),Hainan(HA),Fujian(FJ),Shandong(SD),Sichuan(SC),Chongqing(CQ),and Henan(HN) provinces was high,while in Zhejiang(ZJ),Hubei(HB),Yunnan(YN),and Anhui(AH) provinces,it was low.Tea samples from GD,GX,HA,and FJ provinces were clustered in one group and separated from those from AH and HB provinces.Thus,carbon and nitrogen stable isotope ratio technology could discriminate teas from among some provinces of China,but not from among others.Better separation might be obtained with a combination of isotopic ratios and other indexes,such as elemental data and organic components.
文摘Background:As the demand for traditional Chinese medicinal materials increases in China and even the world,there is an urgent need for an effective and simple identification technology to identify the origin and quality of the latter and ensure the safety of clinical medication.Mineral element analysis and isotope finger-printing are the two commonly used techniques in traditional origin identification.Both of these techniques require the use of stoichiometric methods in the identification process.Although they have high accuracy and sensitivity,they are expensive and inefficient.In addition,near-infrared spectroscopy is a fast,nondestructive,and widely used identification technique developed in recent years,but its identification results are susceptible to samples’states and environmental conditions,and its sensitivity is low.Hyperspectral imaging combines the advantages of imaging technology and optical technology,which can simultaneously access the image information and spectral information which reflect the external characteristics,internal physical structure,and chemical composition of the samples.Hyperspectral imaging is widely applied to agricultural product inspection,but research into its application in origin and quality identification of TCM materials is rare.Methods:In this study,the algorithm framework discriminative marginalized least squares regression(DMLSR)was used for feature extraction of frankincense hyperspectral data.The DMLSR with intraclass compactness graph and manifold regularization can efficiently learn the projective samples with higher separability and less redundant information than the original samples.Then,the discriminative collaborative representation with Tikhonov regularization(DCRT)was applied for classifying the geographical origin and level of frankincense.DCRT introduces the discriminant regularization term and incorporates SID,which is more sensitive to the spectrum as the measurement method and is more suitable for the frankincense spectral data compared with SVM.Results:For the origin classification task,samples of all levels from each origin were,respectively,selected for three-way classification.We used 10-fold cross-validation to select a model parameter in the experiment.When obtaining the optimal parameters,we randomly selected the training set and testing set,where the training set accounts for 70%and the training set for 30%.After repeating this random process 10 times,we obtained the final average classification accuracy,which is higher than 90%,and the standard deviation fluctuation is usually small.For the level classification task,samples of each level from three origins were separately selected for multiclassification.We randomly selected the training set and testing set from each origin.The level classification results of the three origins are good on D4350 data,and the classification accuracy of each level is basically above 80%.Conclusion:Experiments and analysis show that our algorithm framework has excellent classification performance,which is stable in origin classification and has potential for generalization.In addition,the experiments show that in our algorithm framework,different classification tasks need to combine different data sources to achieve better classification and recognition,as the origin classification task uses frankincense’s D3000 data,and level classification task uses frankincense’s D4350 data.
基金supported by the Fundamental Research Funds of Chinese Academy of Forestry(CAF)(CAFYBB2017QC002,CAFYBB2019QD002)。
文摘Place of origin has an important influence on walnut quality and commercial value,which results in the requirement of rapid geographical traceability method.Thus,a method for geographical origin identification of walnuts on the basis of nutritional quality of walnuts from China was conducted.The concentrations of 43 phytochemical components were analyzed in walnut samples from five different walnut-producing regions of China.Based on 14 chemical markers selected by the Random Forest method from these phytochemical components,a new discriminant model for geographical origin was built,with the corresponding correct classification rate of 99.3%.In addition,the quantitative quality differences of walnuts from five regions were analyzed,with values of 0.17–1.43.Moreover,the top three chemical markers for the geographical origin discriminant analysis were Mo,V,and stearic acid,with contribution rates of 26.8%,18.9%,and 10.9%,respectively.This study provides a potentially viable method for application in food authentication.
文摘The <span style="font-family:Verdana;">paper</span><span style="font-family:Verdana;"> presents the results of a study of salt tolerance in some different eco</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">geographical samples of the cotton germplasm collection of the Institute of Genetics and Experimental Biology of the Academy of Sciences of t</span><span style="font-family:Verdana;">he Republic of Uzbekistan. According to the results obtained, the studied samples were divided into several groups </span><span style="font-family:Verdana;">depending on their </span><span style="font-family:;" "=""><span style="font-family:Verdana;">salt tolerance. Salt tolerant and unstable samples were found in all studied ecological and geographical </span><span style="font-family:Verdana;">groups,</span><span style="font-family:Verdana;"> but differ</span></span><span style="font-family:Verdana;">ed</span><span style="font-family:Verdana;"> in the frequency of distribution.</span>
基金a phased achievement of“Misjudgment and Resolution of Origin Tracing in American Public Opinion during the 1918 Influenza Pandemic”(2020LSXH02)a research project of the History Association of the Shanghai Federation of Social Science Associations。
文摘The United States was hard hit by the great influenza pandemic of 1918.The national policy of putting the war first,the unprecedented scale of military training,and the worldwide troop movements and engagement created the conditions for the spread of the pandemic and at the same time seriously weakened US preparedness.The unprecedented pandemic threw American society into extreme panic and spawned all kinds of hypotheses about the pandemic’s geographic origin.Some of the press turned scientifically“tracing the flu”into a succession of pejorative geopolitical exonyms,stigmatizing it as“Spanish flu,”“Russian flu,”“German poisoning,”“Chinese plague,”etc.The groundless ascription of a geographic origin to the influenza pandemic was questioned at the time by insightful American medical professionals and even by Chinese medical experts.In the aftermath of the pandemic,tracking its source became a professional issue of pure medical science,with the search for the pathogen of the pandemic becoming a priority.The discovery and genetic sequencing of the 1918 influenza virus by scientists in the US and other countries led to landmark advances in the discovery of the pathogen,so the importance of tracing it back to its place of origin has taken a back seat.Although evidence of the geographic origin of the 1918 influenza pandemic is not conclusive,medical science has developed enough to disprove the ridiculous“geographic tracking”in the US during the pandemic.
文摘Reflection of ultraviolet (UV) light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, reflect little UV light, while butterflies of the Asian subspecies, P. rapae crucivora, may reflect it strongly or at only intermediate levels. The geographic region where P. rapae originated remains to be determined, Moreover, it is not clear if females with wings that reflect little UV light are ancestral to females with wings that reflect UV strongly or vice versa. In the present study, we aimed to determine the geographic origin and ancestral UV pattern of cabbage butterflies through mitochondrial DNA (mtDNA) sequence analysis and amplified fragment length polymorphism (AFLP) analysis. The results of these investigations suggest that P. rapae is of European origin and that it has expanded its distribution eastward to Asia. It follows that the ancestral subspecies is the type with UV-absorbing wings. Lower nucleotide diversities and haplotype network patterns ofmtDNA derived from East Asian populations suggest that population expansion from Europe to East Asia probably occurred fairly recently and at a rapid rate.