The on-going global pandemic of coronavirus disease 2019(COVID-19)caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been underway for about 11 months.Through November ...The on-going global pandemic of coronavirus disease 2019(COVID-19)caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been underway for about 11 months.Through November 20,2020,51 detection kits for SARS-CoV-2 nucleic acids(24 kits),antibodies(25 kits),or antigens(2 kits)have been approved by the National Medical Products Administration of China(NMPA).Convenient and reliable SARS-CoV-2 detection assays are urgently needed worldwide for strategic control of the pandemic.In this review,the detection kits approved in China are summarised and the three types of tests,namely nucleic acid,serological and antigen detection,which are available for the detection of COVID-19 are discussed in detail.The development of novel detection kits will lay the foundation for the control and prevention of the COVID-19 pandemic globally.展开更多
The SSM （sputum smear microscopy） and five immunochromatographic tuberculosis antibody detection tests （DiaSpot TB, Spodex TB, SD Rapid TB, Clinotech TB Screen and Precious One-step TB） were compared for diagnosis...The SSM （sputum smear microscopy） and five immunochromatographic tuberculosis antibody detection tests （DiaSpot TB, Spodex TB, SD Rapid TB, Clinotech TB Screen and Precious One-step TB） were compared for diagnosis of active TB at the Leprosy and Tuberculosis Referral Hospital, Uzuakoli, Abia State, Nigeria. Sputum specimens from 150 study participants （male/female ratio, 0.81） were cultured on Lowenstein-Jensen slopes and direct smears were stained by Ziehl-Neelsen technique and examined by light microscopy. Sera were tested for anti-TB antibodies using the rapid TB tests. A total of 91 participants were culture positive, 79 （86.8%） for M. tuberculosis and 12 （13.2%） for nontuberculous mycobacteria. The sensitivity of SSM was 50% （95% CI： 39.0-61.0） and specificity was 92.3% （95% CI： 86.4-98.2） in those culture positive for M. tuberculosis. The sensitivity and specificity of the Rapid TB tests ranged from 24.1-39.2% and 78.4-87.8%, respectively. None of the five rapid TB tests had acceptable level of accuracy for diagnosis of active TB. The sensitivity of SSM though moderate is inadequate for long term TB control in this setting.展开更多
Four enzyme immunoassay (EIA) test kits, 1 Canadian product and 3 Chinese products,were used in the comparative study. Each pool consisted of 5 sera, and the 5 single sera were tested as controls. The tests were carri...Four enzyme immunoassay (EIA) test kits, 1 Canadian product and 3 Chinese products,were used in the comparative study. Each pool consisted of 5 sera, and the 5 single sera were tested as controls. The tests were carried out according to the instructions, keeping the same dilution of each serum in single and pool samples. It was found that with the Canadian kit,the positive and negative results of opled sera had no difference from that of the controls (P>0. 10). In the case of Chinese Yali and Kehua kits, the positive results of pooled sera showed no difference from the controls (P >0. 10), but the optical density (OD) of negative opls were increased (P < 0. 01 ), though quite distant from the cut-off values. In the case of Changzheng kit, the OD of opitive opls were significantly lower than those of the controls (P < 0. 05 ), and weak positive samples missed the detection. However this problem could be overcome by blocking the microwells beforehand. Our experiment demonstrate that not all EIA test kits are suitable for screening opls for antithey to hepatitis C virus, and that it is important to assess the sensitivity of the EIA kit to be used for this purpose.展开更多
Objective: The objective of the study is to verify the clinical validity of the following kits with the comparative experimental analysis and evaluate whether their performance can meet the clinical requirements, i.e....Objective: The objective of the study is to verify the clinical validity of the following kits with the comparative experimental analysis and evaluate whether their performance can meet the clinical requirements, i.e. Class III in vitro diagnostic reagent “Herpes Simplex Virus (HSV) Type II Nucleic Acid Detection Kit (PCR-Fluorescence Probe Method)” of Daan Gene Co., Ltd. (Daan kit for short) and “Herpes Simplex Virus (HSV) Type II Nucleic Acid Detection Kit (Fluorescence PCR Method)” of Wuhan Biot Gene Co., Ltd. (Biot kit for short). Method: In the study process, the samples were divided into positive and negative groups according to the control test results, and the clinical application performance of Daan kit and Biot kit was evaluated by comparing their test results. Results: The results show that two kits indicate the same test results, i.e. 26 positive and 107 negative samples in a total of 133 male urethral discharge samples, and 32 positive and 238 negative samples in a total of 270 female cervical secretion samples. Conclusion: It can be concluded from the clinical test that Daan and Biot Herpes Simplex Virus (HSV) Type II Nuc- leic Acid Test Kits are reliable, accurate, safe, convenient for use, stable and high-value in the clinical application.展开更多
BACKGROUND Nucleic acid isolation from formalin-fixed, paraffin-embedded tissue(FFPET)samples is a daily routine in molecular pathology laboratories, but extraction from FFPET is not always easily achieved. Choosing t...BACKGROUND Nucleic acid isolation from formalin-fixed, paraffin-embedded tissue(FFPET)samples is a daily routine in molecular pathology laboratories, but extraction from FFPET is not always easily achieved. Choosing the right extraction technique is key for further examinations.AIM To compare the performance of four commercially available kits used for DNA extraction in routine practice.METHODS DNA isolation was performed on 46 randomly selected formalin-fixed, paraffinembedded(FFPE) colorectal adenocarcinoma(CRC) surgical specimens. Four commercially available extraction kits were used: two for manual DNA extraction(the Pure Link Genomic DNA Mini Kit from Invitrogen and the High Pure FFPE DNA Isolation Kit from Roche) and two for automated DNA extraction(the i Prep Genomic DNA Kit from Invitrogen and the Magna Pure LC DNA Isolation Kit from Roche). The DNA concentration and quality(odds ratio) among the four systems were compared. The results were correlated with the clinicopathological aspects of CRC cases: age, gender, localization, macro-and microscopic features,lymph node metastases, and the lymph node ratio.RESULTS The highest DNA concentration was obtained using the manual kits: 157.24 ±62.99 ng/μL for the Pure Link Genomic DNA Mini Kit and 86.64 ng/μL± 43.84 for the High Pure FFPE DNA Isolation Kit(P < 0.0001). Lower concentrations were obtained with automated systems: 20.39 ± 21.19 ng/μL for the Magna Pure LC DNA Isolation Kit and 8.722 ± 6.408 ng/μL for the i Prep Genomic DNA Kit,with differences between the systems used(P < 0.0001). The comparison between age, gender, tumor localization, pT or pN stage and the lymph node ratio indicated no statistically significant difference in DNA concentration using any of the nucleic acid isolation kits. DNA concentration was influenced by the macroscopic features and grade of differentiation. A higher DNA concentration was obtained for well-differentiated polypoid colorectal adenocarcinomas(CRCs), compared with undifferentiated ulcero-infiltrative carcinomas,irrespective of the kit used.CONCLUSION For research or diagnosis that needs high DNA concentrations, manual methods of DNA isolation should be used. A higher amount of DNA can be obtained from polypoid-type differentiated CRCs. Automated systems confer comfort and a lower amount of DNA that is, however, sufficient for classic polymerase chain reaction(PCR) and real-time quantitative PCR molecular examinations. All four commercially available kits can be successfully used in daily practice.展开更多
Investigations were done on the usefulness of Envirologix CrylAb/CrylAc Plate kits for quantitative analysis of Bt toxin content in transgenic rice grains. Two transgenic rice lines: Kemingdao 1 (KMD1) and Kemingdao 2...Investigations were done on the usefulness of Envirologix CrylAb/CrylAc Plate kits for quantitative analysis of Bt toxin content in transgenic rice grains. Two transgenic rice lines: Kemingdao 1 (KMD1) and Kemingdao 2 (KMD2), transformed with a crylAb gene, and their parental variety, cv. Xiushui 11, were used as positive and negative samples. Results showed that the correlation coefficients as high as 0. 985 - 0. 998, significant at probability level of 0. 05 or 0.01, were obtained for linear regression equations by using the appended calibrators of the kits. No significant differences were detected for values of same rice sample obtained from different trials or by using different lots of the product (kit). The detectable Bt toxin content by this method could be as low as 0.5 ng/g. The Envirologix Kit could be useful for rapid quantitative detection of Bt toxin in rice grains because of its preciseness, simplicity and time saving.展开更多
Sensitivity and specificity of five commonly used rapid malaria test kits in South-South geopolitical zone of Nigeria were analyzed, namely Plasmotest (Biotech International, Germany), Malariatest (Acon Diagnostic, US...Sensitivity and specificity of five commonly used rapid malaria test kits in South-South geopolitical zone of Nigeria were analyzed, namely Plasmotest (Biotech International, Germany), Malariatest (Acon Diagnostic, USA), AcumPF (Acumen, China), PF test (Diaspot, Indonesia) and Malaria P.f. (Global, USA). A total of 200 positive malaria blood sample using microscopy as gold standard and 200 negative were obtained from adult and children. All the kits were tested against these gold standards as directed by the manufacturers. Of the 100 positive gold standard used from children sample, 96% sensitivity were recorded for Biotech, Acon and Global 97%, while Acumen and Diaspot had 99% and 98% respectively. The the highest Specificity was recorded with Biotech 99% both Acumen and Diaspot had 97% specificity. In adult blood sample, there was general reduction in the sensitivity of the test kits. We obtained Sensitivity of 30% with Biotech, 46% with Acon, Global 73%, Diaspot 75%, and Acumen 78%. Considering the increasing influx of MRDT’s into the country, and from the result obtained from this study, there is need for control agensis to ensure that diagnostic test kits be reevaluated before introduction into Nigeria market.展开更多
This paper highlights the importance of adopting use of solar kits to overcome the shortage of electricity supply in the city of Kinshasa instead of polluting generators.Given a need for electricity delivery estimated...This paper highlights the importance of adopting use of solar kits to overcome the shortage of electricity supply in the city of Kinshasa instead of polluting generators.Given a need for electricity delivery estimated at 5 kWh for a poor household of three occupants,a 1 kW solar kit sold for US$990 would perfectly replace SNEL network,the unique electric utility company that uses rolling blackout to handle its low power supply capability within the town,with all the environmental benefits in lieu of a 4 kW power generator sold at US$900 with all the consequences related to the use of fossil fuels in terms of CO2 emissions harmful to health and the environment.Similarly for a middle class household of five occupants,a solar kit of 3 kW to 2,700 dollars or 5 kW to 4,600 dollars is far preferable to an 8 kW generator of US$4,155 which pollutes and entails expenses related to the fuel consumption.展开更多
While consumers use the web to perform routine activities,they are under the constant threat of attack from malicious websites.Even when visiting‘trusted’sites,there is always a risk that site is compromised,and,hos...While consumers use the web to perform routine activities,they are under the constant threat of attack from malicious websites.Even when visiting‘trusted’sites,there is always a risk that site is compromised,and,hosting a malicious script.In this scenario,the injected script would typically force the victim’s browser to undergo a series of redirects before reaching an attacker-controlled domain,which,delivers the actual malware.Although these malicious redirection chains aim to frustrate detection and analysis efforts,they could be used to help identify web-based attacks.Building upon previous work,this paper presents the first known application of a Long Short-Term Memory(LSTM)network to detect Exploit Kit(EK)traffic,utilising the structure of HTTP redirects.Samples are processed as sequences,where each timestep represents a redirect and contains a unique combination of 48 features.The experiment is conducted using a ground-truth dataset of 1279 EK and 5910 benign redirection chains.Hyper-parameters are tuned via K-fold cross-validation(5f-CV),with the optimal configuration achieving an F1 score of 0.9878 against the unseen test set.Furthermore,we compare the results of isolated feature categories to assess their importance.展开更多
The SARS-CoV-2 isothermal amplification detection kits based on loop-mediated isothermal amplification(LAMP)were developed and evaluated on three types samples of SARS-CoV-2.The kits included enzyme reaction mixtures ...The SARS-CoV-2 isothermal amplification detection kits based on loop-mediated isothermal amplification(LAMP)were developed and evaluated on three types samples of SARS-CoV-2.The kits included enzyme reaction mixtures and chromogenic agents.After the isothermal amplification reactions were completed,the reaction results were judged by using the chromogenic agents to determine whether SARS-CoV-2 exists in the samples to be tested.The detection kits have the advantages of convenient operation,fast detection speed and high sensitivity up to 1 copy of virus particles per reaction,which can speed up the detection speed of suspected cases,and avoid the missing detection problems caused by the low detection sensitivity.展开更多
The South African population consists of four ethnic groups,i.e.,Blacks,Coloreds,Indians,and Whites,and is considered the most diverse conglomeration of humans.In addition to autosomal short tandem repeat(STR)variatio...The South African population consists of four ethnic groups,i.e.,Blacks,Coloreds,Indians,and Whites,and is considered the most diverse conglomeration of humans.In addition to autosomal short tandem repeat(STR)variation,an important tool to study population diversity is Y-chromosome(Y)-STR analysis.Y-STRs aid in forensic investigations and provide essential data about paternal lineage origins.Y-STR kits consisting of an array of stable and rapidly mutating markers offer crucial information on a given population’s genetic and haplotype diversity.This review discusses the development of Y-STR kits over the years and highlights some prominent Y-STR studies conducted on the South African population.The earliest Y-STR kit developed was the Y-PLEX™6,with the most recent being the UniQTyper™Y-10 Multiplex.The South African population studies show varying data,with the“minimal haplotype”having low discrimination capacity among the ethnic groups and the UniQTyper™Y-10 showing high genetic diversity among the ethnic groups of the country.There is a dearth of Y-STR studies on the South African population.With the advent of new Y-STR kits with increased discriminatory markers,additional studies are required to represent the South African population in the Y-STR databases.Considering the diversity of the South African population,establishment of a local/regional population database would be beneficial.In addition,data on the origins and prevalence of mutations and silent alleles should be obtained from STR datasets generated during kinship investigations(specifically,parentage tests)so that detailed information about the frequencies of mutations,silent alleles,and uniparental disomy in the South African population at Y STR loci can be estimated.展开更多
站在新世纪的起跑线上,遥望新科技的前景,我们感到绵延了数千年的大同小异的人类生活将发生根本性的巨变。许多传统的、想来无法更改的生活方式,或许将面目一新。 本文的主题句不同凡响,它不是“急吼吼”地去囊括文章的中心思想,而是使...站在新世纪的起跑线上,遥望新科技的前景,我们感到绵延了数千年的大同小异的人类生活将发生根本性的巨变。许多传统的、想来无法更改的生活方式,或许将面目一新。 本文的主题句不同凡响,它不是“急吼吼”地去囊括文章的中心思想,而是使用轻松活泼的语言,轻点主题: Do you dread going to the doctor? In the 2Ist century.you may not have to-self-diagnosis(自我诊断)couldbe as easy as swallowing(吞下)a little pill. 得了病,吞服一粒药丸,诊断随即获得。诊断的结果再被传送到医生那里,而对症下药的处方随即又从医生那儿传送过来。问题就是这么简单！ 本文称这种化验体检的方法为 near-patient tests/on-the-spot checks,其后的同位语对它解释道:testing and diagnosing patients on the spot without theneed to send samples to a laboratory。据此,我们是否可以将它译成:就地检验。 关于此项创造的原动力,文章有所提及: Catering for(迎合)astronauts’medical needs on space missions and themilitary’s need to detect agents(试剂)of biological warfare had provided themain impetus(动力)for the development of the kits, he said. 其中的the military’s need让人感觉不是滋味。人类,展开更多
基金supported by the National Key Program for Infectious Disease of China(2018ZX10101002)the National Key Research and Development Program of China(2016YFD0500301,2020YFC0840900)。
文摘The on-going global pandemic of coronavirus disease 2019(COVID-19)caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been underway for about 11 months.Through November 20,2020,51 detection kits for SARS-CoV-2 nucleic acids(24 kits),antibodies(25 kits),or antigens(2 kits)have been approved by the National Medical Products Administration of China(NMPA).Convenient and reliable SARS-CoV-2 detection assays are urgently needed worldwide for strategic control of the pandemic.In this review,the detection kits approved in China are summarised and the three types of tests,namely nucleic acid,serological and antigen detection,which are available for the detection of COVID-19 are discussed in detail.The development of novel detection kits will lay the foundation for the control and prevention of the COVID-19 pandemic globally.
文摘The SSM （sputum smear microscopy） and five immunochromatographic tuberculosis antibody detection tests （DiaSpot TB, Spodex TB, SD Rapid TB, Clinotech TB Screen and Precious One-step TB） were compared for diagnosis of active TB at the Leprosy and Tuberculosis Referral Hospital, Uzuakoli, Abia State, Nigeria. Sputum specimens from 150 study participants （male/female ratio, 0.81） were cultured on Lowenstein-Jensen slopes and direct smears were stained by Ziehl-Neelsen technique and examined by light microscopy. Sera were tested for anti-TB antibodies using the rapid TB tests. A total of 91 participants were culture positive, 79 （86.8%） for M. tuberculosis and 12 （13.2%） for nontuberculous mycobacteria. The sensitivity of SSM was 50% （95% CI： 39.0-61.0） and specificity was 92.3% （95% CI： 86.4-98.2） in those culture positive for M. tuberculosis. The sensitivity and specificity of the Rapid TB tests ranged from 24.1-39.2% and 78.4-87.8%, respectively. None of the five rapid TB tests had acceptable level of accuracy for diagnosis of active TB. The sensitivity of SSM though moderate is inadequate for long term TB control in this setting.
文摘Four enzyme immunoassay (EIA) test kits, 1 Canadian product and 3 Chinese products,were used in the comparative study. Each pool consisted of 5 sera, and the 5 single sera were tested as controls. The tests were carried out according to the instructions, keeping the same dilution of each serum in single and pool samples. It was found that with the Canadian kit,the positive and negative results of opled sera had no difference from that of the controls (P>0. 10). In the case of Chinese Yali and Kehua kits, the positive results of pooled sera showed no difference from the controls (P >0. 10), but the optical density (OD) of negative opls were increased (P < 0. 01 ), though quite distant from the cut-off values. In the case of Changzheng kit, the OD of opitive opls were significantly lower than those of the controls (P < 0. 05 ), and weak positive samples missed the detection. However this problem could be overcome by blocking the microwells beforehand. Our experiment demonstrate that not all EIA test kits are suitable for screening opls for antithey to hepatitis C virus, and that it is important to assess the sensitivity of the EIA kit to be used for this purpose.
文摘Objective: The objective of the study is to verify the clinical validity of the following kits with the comparative experimental analysis and evaluate whether their performance can meet the clinical requirements, i.e. Class III in vitro diagnostic reagent “Herpes Simplex Virus (HSV) Type II Nucleic Acid Detection Kit (PCR-Fluorescence Probe Method)” of Daan Gene Co., Ltd. (Daan kit for short) and “Herpes Simplex Virus (HSV) Type II Nucleic Acid Detection Kit (Fluorescence PCR Method)” of Wuhan Biot Gene Co., Ltd. (Biot kit for short). Method: In the study process, the samples were divided into positive and negative groups according to the control test results, and the clinical application performance of Daan kit and Biot kit was evaluated by comparing their test results. Results: The results show that two kits indicate the same test results, i.e. 26 positive and 107 negative samples in a total of 133 male urethral discharge samples, and 32 positive and 238 negative samples in a total of 270 female cervical secretion samples. Conclusion: It can be concluded from the clinical test that Daan and Biot Herpes Simplex Virus (HSV) Type II Nuc- leic Acid Test Kits are reliable, accurate, safe, convenient for use, stable and high-value in the clinical application.
基金the University of Medicine,Pharmacy,Science and Technology Research Grant,No.275/11.01.2017
文摘BACKGROUND Nucleic acid isolation from formalin-fixed, paraffin-embedded tissue(FFPET)samples is a daily routine in molecular pathology laboratories, but extraction from FFPET is not always easily achieved. Choosing the right extraction technique is key for further examinations.AIM To compare the performance of four commercially available kits used for DNA extraction in routine practice.METHODS DNA isolation was performed on 46 randomly selected formalin-fixed, paraffinembedded(FFPE) colorectal adenocarcinoma(CRC) surgical specimens. Four commercially available extraction kits were used: two for manual DNA extraction(the Pure Link Genomic DNA Mini Kit from Invitrogen and the High Pure FFPE DNA Isolation Kit from Roche) and two for automated DNA extraction(the i Prep Genomic DNA Kit from Invitrogen and the Magna Pure LC DNA Isolation Kit from Roche). The DNA concentration and quality(odds ratio) among the four systems were compared. The results were correlated with the clinicopathological aspects of CRC cases: age, gender, localization, macro-and microscopic features,lymph node metastases, and the lymph node ratio.RESULTS The highest DNA concentration was obtained using the manual kits: 157.24 ±62.99 ng/μL for the Pure Link Genomic DNA Mini Kit and 86.64 ng/μL± 43.84 for the High Pure FFPE DNA Isolation Kit(P < 0.0001). Lower concentrations were obtained with automated systems: 20.39 ± 21.19 ng/μL for the Magna Pure LC DNA Isolation Kit and 8.722 ± 6.408 ng/μL for the i Prep Genomic DNA Kit,with differences between the systems used(P < 0.0001). The comparison between age, gender, tumor localization, pT or pN stage and the lymph node ratio indicated no statistically significant difference in DNA concentration using any of the nucleic acid isolation kits. DNA concentration was influenced by the macroscopic features and grade of differentiation. A higher DNA concentration was obtained for well-differentiated polypoid colorectal adenocarcinomas(CRCs), compared with undifferentiated ulcero-infiltrative carcinomas,irrespective of the kit used.CONCLUSION For research or diagnosis that needs high DNA concentrations, manual methods of DNA isolation should be used. A higher amount of DNA can be obtained from polypoid-type differentiated CRCs. Automated systems confer comfort and a lower amount of DNA that is, however, sufficient for classic polymerase chain reaction(PCR) and real-time quantitative PCR molecular examinations. All four commercially available kits can be successfully used in daily practice.
文摘Investigations were done on the usefulness of Envirologix CrylAb/CrylAc Plate kits for quantitative analysis of Bt toxin content in transgenic rice grains. Two transgenic rice lines: Kemingdao 1 (KMD1) and Kemingdao 2 (KMD2), transformed with a crylAb gene, and their parental variety, cv. Xiushui 11, were used as positive and negative samples. Results showed that the correlation coefficients as high as 0. 985 - 0. 998, significant at probability level of 0. 05 or 0.01, were obtained for linear regression equations by using the appended calibrators of the kits. No significant differences were detected for values of same rice sample obtained from different trials or by using different lots of the product (kit). The detectable Bt toxin content by this method could be as low as 0.5 ng/g. The Envirologix Kit could be useful for rapid quantitative detection of Bt toxin in rice grains because of its preciseness, simplicity and time saving.
文摘Sensitivity and specificity of five commonly used rapid malaria test kits in South-South geopolitical zone of Nigeria were analyzed, namely Plasmotest (Biotech International, Germany), Malariatest (Acon Diagnostic, USA), AcumPF (Acumen, China), PF test (Diaspot, Indonesia) and Malaria P.f. (Global, USA). A total of 200 positive malaria blood sample using microscopy as gold standard and 200 negative were obtained from adult and children. All the kits were tested against these gold standards as directed by the manufacturers. Of the 100 positive gold standard used from children sample, 96% sensitivity were recorded for Biotech, Acon and Global 97%, while Acumen and Diaspot had 99% and 98% respectively. The the highest Specificity was recorded with Biotech 99% both Acumen and Diaspot had 97% specificity. In adult blood sample, there was general reduction in the sensitivity of the test kits. We obtained Sensitivity of 30% with Biotech, 46% with Acon, Global 73%, Diaspot 75%, and Acumen 78%. Considering the increasing influx of MRDT’s into the country, and from the result obtained from this study, there is need for control agensis to ensure that diagnostic test kits be reevaluated before introduction into Nigeria market.
文摘This paper highlights the importance of adopting use of solar kits to overcome the shortage of electricity supply in the city of Kinshasa instead of polluting generators.Given a need for electricity delivery estimated at 5 kWh for a poor household of three occupants,a 1 kW solar kit sold for US$990 would perfectly replace SNEL network,the unique electric utility company that uses rolling blackout to handle its low power supply capability within the town,with all the environmental benefits in lieu of a 4 kW power generator sold at US$900 with all the consequences related to the use of fossil fuels in terms of CO2 emissions harmful to health and the environment.Similarly for a middle class household of five occupants,a solar kit of 3 kW to 2,700 dollars or 5 kW to 4,600 dollars is far preferable to an 8 kW generator of US$4,155 which pollutes and entails expenses related to the fuel consumption.
文摘While consumers use the web to perform routine activities,they are under the constant threat of attack from malicious websites.Even when visiting‘trusted’sites,there is always a risk that site is compromised,and,hosting a malicious script.In this scenario,the injected script would typically force the victim’s browser to undergo a series of redirects before reaching an attacker-controlled domain,which,delivers the actual malware.Although these malicious redirection chains aim to frustrate detection and analysis efforts,they could be used to help identify web-based attacks.Building upon previous work,this paper presents the first known application of a Long Short-Term Memory(LSTM)network to detect Exploit Kit(EK)traffic,utilising the structure of HTTP redirects.Samples are processed as sequences,where each timestep represents a redirect and contains a unique combination of 48 features.The experiment is conducted using a ground-truth dataset of 1279 EK and 5910 benign redirection chains.Hyper-parameters are tuned via K-fold cross-validation(5f-CV),with the optimal configuration achieving an F1 score of 0.9878 against the unseen test set.Furthermore,we compare the results of isolated feature categories to assess their importance.
基金supported by Key Basic Research Program of China(No.2017YFA0205304)Nature Scientific Foundation of China(No.81602184)+1 种基金Medical Engineering Cross Project of Shanghai Jiao Tong University(YG2017ZD12)supported by“the Belt and Road”young scientist exchange program of the Science and Technology Commission of Shanghai(Grant No.18410741600).
文摘The SARS-CoV-2 isothermal amplification detection kits based on loop-mediated isothermal amplification(LAMP)were developed and evaluated on three types samples of SARS-CoV-2.The kits included enzyme reaction mixtures and chromogenic agents.After the isothermal amplification reactions were completed,the reaction results were judged by using the chromogenic agents to determine whether SARS-CoV-2 exists in the samples to be tested.The detection kits have the advantages of convenient operation,fast detection speed and high sensitivity up to 1 copy of virus particles per reaction,which can speed up the detection speed of suspected cases,and avoid the missing detection problems caused by the low detection sensitivity.
文摘The South African population consists of four ethnic groups,i.e.,Blacks,Coloreds,Indians,and Whites,and is considered the most diverse conglomeration of humans.In addition to autosomal short tandem repeat(STR)variation,an important tool to study population diversity is Y-chromosome(Y)-STR analysis.Y-STRs aid in forensic investigations and provide essential data about paternal lineage origins.Y-STR kits consisting of an array of stable and rapidly mutating markers offer crucial information on a given population’s genetic and haplotype diversity.This review discusses the development of Y-STR kits over the years and highlights some prominent Y-STR studies conducted on the South African population.The earliest Y-STR kit developed was the Y-PLEX™6,with the most recent being the UniQTyper™Y-10 Multiplex.The South African population studies show varying data,with the“minimal haplotype”having low discrimination capacity among the ethnic groups and the UniQTyper™Y-10 showing high genetic diversity among the ethnic groups of the country.There is a dearth of Y-STR studies on the South African population.With the advent of new Y-STR kits with increased discriminatory markers,additional studies are required to represent the South African population in the Y-STR databases.Considering the diversity of the South African population,establishment of a local/regional population database would be beneficial.In addition,data on the origins and prevalence of mutations and silent alleles should be obtained from STR datasets generated during kinship investigations(specifically,parentage tests)so that detailed information about the frequencies of mutations,silent alleles,and uniparental disomy in the South African population at Y STR loci can be estimated.
文摘站在新世纪的起跑线上,遥望新科技的前景,我们感到绵延了数千年的大同小异的人类生活将发生根本性的巨变。许多传统的、想来无法更改的生活方式,或许将面目一新。 本文的主题句不同凡响,它不是“急吼吼”地去囊括文章的中心思想,而是使用轻松活泼的语言,轻点主题: Do you dread going to the doctor? In the 2Ist century.you may not have to-self-diagnosis(自我诊断)couldbe as easy as swallowing(吞下)a little pill. 得了病,吞服一粒药丸,诊断随即获得。诊断的结果再被传送到医生那里,而对症下药的处方随即又从医生那儿传送过来。问题就是这么简单！ 本文称这种化验体检的方法为 near-patient tests/on-the-spot checks,其后的同位语对它解释道:testing and diagnosing patients on the spot without theneed to send samples to a laboratory。据此,我们是否可以将它译成:就地检验。 关于此项创造的原动力,文章有所提及: Catering for(迎合)astronauts’medical needs on space missions and themilitary’s need to detect agents(试剂)of biological warfare had provided themain impetus(动力)for the development of the kits, he said. 其中的the military’s need让人感觉不是滋味。人类,
