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| 1 | Investigating the impact of Glyoxal retrieval from MAX-DOAS observations during haze and non-haze conditions in Beijing显示文摘This study presents the Multi Axis Differential Optical Absorption Spectroscopy(MAXDOAS) measurements for Glyoxal(CHOCHO) in Beijing, China(39.95°N, 116.32°E). CHOCHO is the smallest compound of di-carbonyl group. As a primary sink of CHOCHO, its photolysis with NOx(oxides of nitrogen) results in the production of tropospheric ozone. Therefore,the focus of CHOCHO DOAS measurements is increasing in trend. We did the measurements from 09 May 2017 to 09 September 2017. The study was conducted to compare different retrieval settings in order to reveal best DOAS fit settings for CHOCHO;furthermore, effect of haze and non-haze days on CHOCHO concentration was examined.The root mean square of residual and Differential Slant Column density(dSCD) error was reduced when measurements were done with lower wavelength limit around 432–438 nm and upper intervals around 455–460 nm. Thus, lower wavelength intervals around432–438 nm and upper intervals around 457–460 nm were best for the retrieval of dSCDs for CHOCHO. Meteorological conditions like haze or non-haze days did not have significant effect on DOAS fit parameters. The CHOCHO vertical column densities range from 1.33 E +14 to 9.77 E + 14 molecules/cm2 during the study period with average of 6.16 E +14 molecules/cm2. The results indicated that during haze days CHOCHO concentration was higher because of lower rate of photolysis and atmospheric oxidation potential. Our results did not show any significant weekend effect on CHOCHO atmospheric concentration. | Zeeshan Javed Cheng Liu Muhammad Fahim Khokhar Chengzhi Xing Wei Tan Muhammad Ahmed Subhani Abdul Rehman Aimon Tanvir | 2019 | Journal of Environmental Sciences2019，31，6： | 3 |
| 2 | Regulatory mechanisms of microbial homeostasis in insect gut显示文摘Insects live in incredibly complex environments.The intestinal epithelium of insects is in constant contact with microorganisms,some of which are beneficial and some harmful to the host.Insect gut health and function are maintained through multidimensional mechanisms that can proficiently remove foreign pathogenic microorganisms while effectively maintaining local symbiotic microbial homeostasis.The basic immune mechanisms of the insect gut,such as the dual oxidase-reactive oxygen species(Duox-ROS)system and the immune deficiency(Imd)-signaling pathway,are involved in the maintenance of microbial homeostasis.This paper reviews the role of physical defenses,the Duox-ROS and Imd signaling pathways,the Janus kinase/signal transducers and activators of transcription signaling pathway,and intestinal symbiotic flora in the homeostatic maintenance of the insect gut microbiome. | Shuai Bai Zhichao Yao Muhammad Fahim Raza Zhaohui Cai Hongyu Zhang | 2021 | Insect Science2021，28，2： | 3 |
| 3 | Spatial variance and assessment of nitrogen dioxide pollution in major cities of Pakistan along N5-Highway显示文摘This paper discusses the findings of the first car MAX-DOAS(multi-axis differential optical absorption spectroscopy) field campaign(300 km long) along the National Highway-05(N5-Highway) of Pakistan conducted on 13 and 14 November, 2012. The main objective of the field campaign was to assess the spatial distribution of tropospheric nitrogen dioxide(NO_2)columns and corresponding concentrations along the N5-Highway from Islamabad to Lahore.Source identification of NO_2 revealed that the concentrations were higher within major cities along the highway. The highest NO_2 vertical column densities(NO_2VCDs) were found around two major cities of Rawalpindi and Lahore. This study also presents a comparison of NO_2 VCDs measured by the ozone monitoring instrument(OMI) and car MAX-DOAS observations. The comparison revealed similar spatial distribution of the NO_2 columns with both car MAX-DOAS and satellite observations, but the car MAX-DOAS observations show much more spatial details. Maximum NO_2 VCD retrieved from car MAX-DOAS observations was up to an order of magnitude larger than the OMI observations in urban areas. | Yasir Shabbir Muhammad Fahim Khokhar Reza Shaiganfar Thomas Wagner | 2016 | Journal of Environmental Sciences2016，28，5： | 1 |
| 4 | Physico-chemical analysis and antimicrobial potential of Apis dorsata,Apis mellifera and Ziziphus jujube honey samples from Pakistan显示文摘Objective:To evaluale physico-chemical properties and antimicrobial potential of indigenous honey samples against different reference strains including Escherichia coli ATCC 8739.Enterobacter aerogenes ATCC 13048.Pseudomonas aeruginosa ATCC 9027.Bacillus subtilis ATCC6633.Staphylococcus aureus ATCC 25923.Salmonella typhi ATCC 14028,Klebsiella pneumonia ATCC 13883.Aspergillus niger ATCC 16404.Rhizopus oligasparus PCSIR1.Candida albicans ATCC14053 and Candida utilis ATCC 9950.Methods:By using standard methods samples were evaluated for their antimicrobial properties including additive effect of starch and non—peroxidase activity,antioxidative properties(phenol contents,flavonoid contents,1,1-diphenyl-2-pierylhydrazyl radical scavenging activity).Prior to this evaluation,complete physico-chemical properties including pH,color,ash contents,protein contents,moisture contents,hydroxymethyl furfural contents,total sugar contents,reducing sugar and non-reducing sugar contents were analyzed.Results:Relatively higher ash contents were found in the Siddar honey i.e.(0.5900±0.0336)%and small honey showed relatively higher protein contents i.e.(777.598±9.880) mg/kg.The moisture contents of tested honey samples ranged between 13.8%—16,6%,total sugar contents foam 61.672%-72.420%and non-reducing sugar contents from 1.95%—3.93%.Presences of phenolic contents indicate higher antioxidant potential of these honey samples.All bacteria showed clear inhibition zones in response to tested honey samples whereas fungi and yeast showed inhibition at higher concentrations of these honey samples.For Escherichia coli.Bacillus subtilis.Salmonella typhi.Pseudomonas aeruginosa and Aspergillus niger,overall the small honey showed the higher activity than other honey samples.Conclusion:Physico-chemical analysis of honey samples confirmed good quality of honey according to the standards set by European Union Commission and Codex Alimcntarius Commission.Evaluation of these honey samples confirms antimicrobial potential of particular types of honeys indigenous to Pakistan. | Hira Fahim Javid Iqbal Dasti Ihsan Ali Safia Ahmed Muhammad Nadeem | 2014 | Asian Pacific Journal of Tropical Biomedicine2014，4，8： | 1 |
| 5 | Spatio-temporal variations in trends of vegetation and drought changes in relation to climate variability from 1982 to 2019 based on remote sensing data from East Asia显示文摘Studying the significant impacts on vegetation of drought due to global warming is crucial in order to understand its dynamics and interrelationships with temperature,rainfall,and normalized difference vegetation index(NDVI).These factors are linked to excesses drought frequency and severity on the regional scale,and their effect on vegetation remains an important topic for climate change study.East Asia is very sensitive and susceptible to climate change.In this study,we examined the effect of drought on the seasonal variations of vegetation in relation to climate variability and determined which growing seasons are most vulnerable to drought risk;and then explored the spatio-temporal evolution of the trend in drought changes in East Asia from 1982 to 2019.The data were studied using a series of several drought indexes,and the data were then classified using a heat map,box and whisker plot analysis,and principal component analysis.The various drought indexes from January to August improved rapidly,except for vegetation health index(VHI)and temperature condition index(TCI).While these indices were constant in September,they increased again in October,but in December,they showed a descending trend.The seasonal and monthly analysis of the drought indexes and the heat map confirmed that the East Asian region suffered from extreme droughts in 1984,1993,2007,and 2012among the study years.The distribution of the trend in drought changes indicated that more severe drought occurred in the northwestern region than in the southeastern area of East Asia.The drought tendency slope was used to describe the changes in drought events during 1982–2019 in the study region.The correlations among monthly precipitation anomaly percentage(NAP),NDVI,TCI,vegetation condition index(VCI),temperature vegetation drought index(TVDI),and VHI indicated considerably positive correlations,while considerably negative correlations were found among the three pairs of NDVI and VHI,TVDI and VHI,and NDVI and TCI.This ecological and climatic mechanism provides a good basis for the assessment of vegetation and drought-change variations within the East Asian region.This study is a step forward in monitoring the seasonal variation of vegetation and variations in drought dynamics within the East Asian region,which will serve and contribute to the better management of vegetation,disaster risk,and drought in the East Asian region. | Shahzad ALI Abdul BASIT Muhammad UMAIR Tyan Alice MAKANDA Fahim Ullah KHAN Siqi SHI NI Jian | 2023 | Journal of Integrative Agriculture2023，22，10： | 0 |
| 6 | Effect of eccentricity in reinforced concrete beam-column-slab connection under cyclic loading显示文摘Beam-column connections are one of the most critical elements of reinforced concrete structures,especially in seismically active regions,and have been extensively evaluated experimentally and numerically.However,very limited experimental studies about eccentric reinforced concrete connections including the effect of connected slabs are available.This study presents the experimental results of two half-scale eccentric beam-column-slab connections subjected to quasi-static cyclic loading.The horizontal eccentricity(eh)is maintained at 12.5%and 25%of column width(bc)for specimens 1 and 2,respectively.The damage pattern,performance levels,displacement ductility(μD),energy dissipation,and connection strength and stiffness are compared for both specimens,and the effect of eccentricity is evaluated.It is concluded that the eccentricity has no significant effect on the lateral load carrying capacity;however,the overall strength degradation increases with the increase in eccentricity.Similarly,the elastic stiffness of specimen 2 decreased by 14%as the eccentricity increased from 12.5%to 25%;however,the eccentricity had no significant effect on the overall stiffness degradation.μD decreased by 43%,and the energy dissipation capacity decreased by 40%in specimen 2 with higher eccentricity.The story drifts corresponding to the performance levels of the life safety(LS)and collapse prevention(CP)were found to be 28%lesser in specimen 2 than in specimen 1. | Rooh ULLAH Amjad NASEER Muhammad FAHIM Mohammad ASHRAF Eid BADSHAH | 2021 | Frontiers of Structural and Civil Engineering2021，15，2： | 0 |
| 7 | Identification of Software Bugs by Analyzing Natural Language-Based Requirements Using Optimized Deep Learning Features显示文摘Software project outcomes heavily depend on natural language requirements,often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements.Researchers are exploring machine learning to predict software bugs,but a more precise and general approach is needed.Accurate bug prediction is crucial for software evolution and user training,prompting an investigation into deep and ensemble learning methods.However,these studies are not generalized and efficient when extended to other datasets.Therefore,this paper proposed a hybrid approach combining multiple techniques to explore their effectiveness on bug identification problems.The methods involved feature selection,which is used to reduce the dimensionality and redundancy of features and select only the relevant ones;transfer learning is used to train and test the model on different datasets to analyze how much of the learning is passed to other datasets,and ensemble method is utilized to explore the increase in performance upon combining multiple classifiers in a model.Four National Aeronautics and Space Administration(NASA)and four Promise datasets are used in the study,showing an increase in the model’s performance by providing better Area Under the Receiver Operating Characteristic Curve(AUC-ROC)values when different classifiers were combined.It reveals that using an amalgam of techniques such as those used in this study,feature selection,transfer learning,and ensemble methods prove helpful in optimizing the software bug prediction models and providing high-performing,useful end mode. | Qazi Mazhar ul Haq Fahim Arif Khursheed Aurangzeb Noor ul Ain Javed Ali Khan Saddaf Rubab Muhammad Shahid Anwar | 2024 | Computers, Materials & Continua2024，78，3： | 0 |
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