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Observational Characteristics of Cloud Radiative Effects over Three Arid Regions in the Northern Hemisphere

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Journal of Meteorological Research 2017年第4期31卷 654-664页

作者： Jiandong LI Tianhe WANG ammara HABIB State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University

Cloud–radiation processes play an important role in regional energy budgets and surface temperature changes over arid regions. Cloud radiative effects（CREs） are used to quantitatively measure the aforementioned climatic role. This study investigates the characteristics of CREs and their temporal variations over three arid regions in central Asia（CA）, East Asia（EA）, and North America（NA）, based on recent satellite datasets. Our results show that the annual mean shortwave（SW） and net CREs（SWCRE and NCRE） over the three arid regions are weaker than those in the same latitudinal zone of the Northern Hemisphere. In most cold months（November–March）, the longwave（LW）CRE is stronger than the SWCRE over the three arid regions, leading to a positive NCRE and radiative warming in the regional atmosphere–land surface system. The cold-season mean NCRE at the top of the atmosphere（TOA） averaged over EA is 4.1 W m^-2, with a positive NCRE from November to March, and the intensity and duration of the positive NCRE is larger than that over CA and NA. The CREs over the arid regions of EA exhibit remarkable annual cycles due to the influence of the monsoon in the south. The TOA LWCRE over arid regions is closely related to the high-cloud fraction, and the SWCRE relates well to the total cloud fraction. In addition, the relationship between the SWCRE and the low-cloud fraction is good over NA because of the considerable occurrence of low cloud. Further results show that the interannual variation of TOA CREs is small over the arid regions of CA and EA, but their surface LWCREs show certain decreasing trends that correspond well to their decreasing total cloud fraction. It is suggested that combined studies of more observational cloud properties and meteorological elements are needed for indepth understanding of cloud–radiation processes over arid regions of the Northern Hemisphere.

关键词： arid region cloud fraction cloud radiative effects

Concentrations and chemical compositions of PM10 during hazy and non-hazy days in Beijing

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Journal of Environmental Sciences 2020年第1期32卷 1-9页

作者： Xianchu Wu Bin Chen Tianxue Wen ammara Habib Guangyu Shi Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China

In order to study the concentrations of major components,characteristics and comparison in hazy and non-hazy days of PM10 in Beijing,aerosol samples were collected at urban site in Beijing from December 29,2014 to January 22,*** metals like Zn,Pb,Mn,Cu,As,V,Cr and Cd were deeply studied considering their toxic effects on human being;nine water-soluble inorganic ions(SO4^2-,NO3^-,NH4^+,Na^+,K^+,Cl^-,Ca^2+and Mg^2+)and carbon fractions(OC and EC)were also *** concentrations of heavy metals were 1.03–1.98 times higher in hazy days than those in non-hazy days,mainly due to biomass burning and coal *** trends in total heavy metals concentrations were basically consistent with the trends in PM concentrations except for two obvious periods(12.29–12.30;1.14–1.15);but when air masses accumulated locally or around Beijing,trends in PM concentrations and heavy metals were *** proportion for NO3^-/SO4^2-indicated that mobile sources such as automobiles were important reasons for haze in *** between OC and EC during non-hazy days was strong(R^2=0.95)but it was low(R^2=0.67)during hazy days,and large variations for OC/EC values occurred in hazy *** calculated mass concentration of SOC is 2.58μg/m^3,which only accounted for 10.1%of the OC *** air masses from the far north-west,they decreased PM concentration in Beijing and they were relatively clean;however,those from the near east,south-east and south of the mainland increased PM concentration and they were dirty.

关键词： PM10 Haze Beijing Chemical composition Air mass

Rice Curled Its Leaves Either Adaxially or Abaxially to Combat Drought Stress

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Rice science 2023年第5期30卷 405-416页

作者： ammara LATIF SUN Ying PU Cuixia Noman ALI Ministry of Education Key Laboratory of Molecular and Cellular Biology Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation/Hebei Key Laboratory of Molecular and Cellular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang 050024China Department of Botany Government College UniversityFaisalabad 38000Pakistan

Leaf rolling(LR)is one of the defensive mechanisms that plants have developed against adverse environmental *** is a typical drought response,promoting drought resistance in various gramineae species,including wheat,maize,and *** cultivation faces the formidable challenge of water deprivation because of its high water requirements,which leads to drought-related symptoms in *** is an important morphological characteristic that plays a key role in controlling water loss during water insufficiency,thereby regulating leaf area and stature,which are crucial agronomic traits determining yield ***,sclerenchyma,mesophyll,and vascular bundles are the cells that engage in LR and commonly exhibit adaxial or abaxial types of rolling in *** specific genes linked to rolling,either adaxially or abaxially,are discussed *** addition to the factors influencing LR,here is a short review of the morphological,physiological and molecular responses of this adaptation under drought ***,this review highlights how LR combats the consequences of drought *** eco-physiological and molecular mechanisms underlying this morphological adaptation in rice should be further explored,as they might be useful in dealing with various degrees of drought tolerance.

关键词： adaxial/abaxial rolling drought stress leaf rolling molecular mechanism rice physiological response transcript factor

Uniform and Homogeneous Growth of Copper Nanoparticles on Electrophoretically Deposited Carbon Nanotubes Electrode for Nonenzymatic Glucose Sensor

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 889-894页

作者： Syeda ammara Shahzadi Shamaila Rehana Sharif Sheeba Ghani Nosheen Zafar Department of Physics University of Engineering and Technology Department of Physics Forman Christian College (A Chartered University)

The multiwalled carbon nanotubes thin-film-based electrode was fabricated by electrophoretic deposition and modified with copper （Cu） nanoparticles to fabricate Cu/CNTs nanocomposite sensor for nonenzymatic glucose detection. The expensive glassy carbon electrode was replaced by fluorine-doped tin oxide glass containing CNTs film to confine the Cu nanoparticles growth by electrodeposition through cyclic voltammetry （CV）. The ultraviolet visible and X-ray diffraction analysis revealed the successful deposition of Cu nanoparticles on the CNTs-modified electrode. The atomic force microscopy images confirrqed the morphology of electrodeposited Cu on CNTs film as uniformly dispersed particles. The electrocatalytic activity of electrode to the glucose oxidation was investigated in alkaline medium by CV and amperometric measurements. The fabricated sensor exhibited a fast response time of less than 5 s and the sensitivity of 314 μA rnM^-1 cm^-2 with linear concentration range （0.02-3.0 mM） having detection limit 10.0 μM. Due to simple preparation of sensor, Cu/CNTs nanocomposite electrodes are a suitable candidate for reliable determination of glucose with good stability.

关键词： Electrophoretic deposition (EPD) Fluorine-doped tin oxide (FTO) substrate Carbon nanotubes Copper nanoparticles Nonenzymatic electrocatalysis Glucose sensor

A Soil Moisture Data Assimilation System for Pakistan Using PODEn4DVar and CLM4.5

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Journal of Meteorological Research 2019年第6期33卷 1182-1193页

作者： Tariq MAHMOOD Zhenghui XIE Binghao JIA ammara HABIB Rashid MAHMOOD State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Pakistan Meteorological Department Islamabad 44000Pakistan Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Soil moisture is an important state variable for land–atmosphere *** is a vital land surface variable for research on hydrology,agriculture,climate,and drought *** current study,a soil moisture data assimilation framework has been developed by using the Community Land Model version 4.5(CLM4.5)and the proper orthogonal decomposition(POD)-based ensemble four-dimensional variational assimilation(PODEn4 DVar)*** experiments were conducted at four agricultural sites in Pakistan by assimilating in-situ soil moisture *** results showed that it was a reliable *** quantify further the feasibility of the data assimilation(DA)system,soil moisture observations from the top four soil-depths(0–5,5–10,10–20,and 20–30 cm)were *** evaluation results indicated that the DA system improved soil moisture *** addition,updating the soil moisture in the upper soil layers of CLM4.5 could improve soil moisture estimation in deeper soil layers[layer 7(L7,62.0 cm)and layer 8(L8,103.8 cm)].To further evaluate the DA system,observing system simulation experiments(OSSEs)were designed for Pakistan by assimilating daily *** idealized experiments produced statistical results that had higher correlation coefficients,reduced root mean square errors,and lower biases for assimilation,which showed that the DA system is able to produce and improve soil moisture estimation in Pakistan.

关键词： PODEn4DVar Community Land Model version 4.5 data assimilation soil moisture Pakistan

Road to recompensation:BavenoⅦcriteria and transjugular intrahepatic portosystemic shunt in liver cirrhosis

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World Journal of Gastroenterology 2024年第32期30卷 3743-3747页

作者： Muhammad Aarish Anis ammara Abdul Majeed Shahab Abid Department of Medicine Section of GastroenterologyAga Khan University HospitalSindhKarachi 74800Pakistan

Liver cirrhosis has long been considered a point of no return,with limited hope for ***,recent advancements,particularly the Baveno VII criteria and the utilization of transjugular intrahepatic portosystemic shunt(TIPS),have illuminated the concept of hepatic *** this editorial we comment on the article by Gao et al published in the recent *** editorial provides a comprehensive overview of the evolution of understanding cirrhosis,the criteria for recompensation,and the efficacy of TIPS in achieving *** discuss key findings from recent studies,including the promising outcomes observed in patients who achieved recompensation post-TIPS *** further research is needed to validate these findings and elucidate the mechanisms underlying recompensation,the insights presented here offer renewed hope for patients with decompensated cirrhosis and highlight the potential of TIPS as a therapeutic option in their management.

关键词： Decompensated hepatic cirrhosis Hepatic recompensation Transjugular intrahepatic portosystemic shunt Variceal bleeding Refractory ascites

Crimean-Congo hemorrhagic fever: etiology, diagnosis, management and potential alternative therapy

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 143-151页

作者： Mohammad Saleem Muiz Tanvir Muhammad Furqan Akhtar ammara Saleem Department of Pharmacology Punjab University College of PharmacyUniversity of the PunjabLahorePakistan Department of Pharmacology Faculty of Pharmaceutical SciencesGovernment College University FaisalabadFaisalabadPakistan Riphah Institute of Pharmaceutical Sciences Riphah International UniversityLahore CampusPakistan

Crimean-Congo hemorrhagic fever(CCHF)virus belongs to the genus Nairovirus and family *** is a tickborne disease that has mostly been reported from Asia,Africa and *** diagnosis of CCHF is essential for patient care and preventing its spread to normal *** of CCHF is mostly limited to the use of ribavirin and palliative *** practice of using interferon and vaccines has also been proved to be ineffective and unsafe.A search for an effective alternative treatment of the CCHF still ***,the current review focusses on the cause,prevalence,mode of transmission,pathophysiology,signs,symptoms,diagnostic features and treatment options of *** review also highlights the possible alternative therapy in the form of antiviral medicinal plants which are effective against viral hemorrhagic *** medicinal plants have shown convincing evidence for their activities against different viral hemorrhagic fevers and may be used alone or in combination with existing therapies to achieve an optimum therapeutic response.

关键词： Congo fever Dengue fever Alternative therapy Antiviral plants

BN-GEPSO:Learning Bayesian Network Structure Using Generalized Particle Swarm Optimization

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Computers, Materials & Continua 2023年第5期75卷 4217-4229页

作者： Muhammad Saad Salman Ibrahim M.Almanjahie AmanUllah Yasin ammara Nawaz Cheema Air University Islamabad44000Pakistan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia

At present Bayesian Networks(BN)are being used widely for demonstrating uncertain knowledge in many disciplines,including biology,computer science,risk analysis,service quality analysis,and *** they suffer from the problem that when the nodes and edges increase,the structure learning difficulty increases and algorithms become *** solve this problem,heuristic optimization algorithms are used,which tend to find a near-optimal answer rather than an exact one,with particle swarm optimization(PSO)being one of *** is a swarm intelligence-based algorithm having basic inspiration from flocks of birds(how they search for food).PSO is employed widely because it is easier to code,converges quickly,and can be parallelized *** use a recently proposed version of PSO called generalized particle swarm optimization(GEPSO)to learn bayesian network *** construct an initial directed acyclic graph(DAG)by using the max-min parent’s children(MMPC)algorithm and cross relative average *** used to create a population for theGEPSO optimization ***,we propose a velocity update procedure to increase the efficiency of the algorithmic search *** of the experiments show that as the complexity of the dataset increases,our algorithm Bayesian network generalized particle swarm optimization(BN-GEPSO)outperforms the PSO algorithm in terms of the Bayesian information criterion(BIC)score.

关键词： Bayesian network structure learning particle swarm optimization

A case study of cold-seasonthundersnow in Beijing

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Atmospheric and Oceanic Science Letters 2019年第6期12卷 392-398页

作者： JIAO Reguang CHEN Bin HABIB ammara SHI Guangyu Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjingChina

The characteristics of local thundersnow at ne spatiotemporal scale on 9 and 10 November 2009 in Beijing were analyzed,using wind pro ler,microwave radiometer,automatic weather station,Doppler weather radar,and satellite ***,the causes of winter convection are *** results showed that it was reflux *** cause of the thunder and lightning was the elevated convection above the lower cold and dry air,and the trigger for convection was the short wave trough and convergencein the middle *** thundersnow event developed from monsoon-like long-lasting water vapor transport at 850 hPa from the South China Sea along with strong instability of,and convergence in,the conveyor layer.

关键词： Thundersnow reflux doppler radar wind profiler radiometer