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Journal of Forestry Research 2018年第1期29卷 129-137页

作者： parveen kumar Chhetri Department of Geography Texas A&M UniversityCollege Station

The natural upper boundary of a forest（forest line） in mountain environments is an indicator of climate conditions. An increase in global average temperatures has resulted in an upward advance of the forest line. This advance may result in fragmentation of the alpine ecosystem and a loss of biodiversity. Therefore, it is important to identify potential areas where current forests can advance under scenarios of future climate change. I used expert knowledge and cartographic modeling to create a hybrid cartographic model considering five topographic variables to predict areas where forest line can expand in the *** prediction accuracy of the model is around 82%. The model is able to predict areas above the current forest line that are suitable or unsuitable for future forest *** inclusion of high-resolution satellite imagery and digital elevation models, as well as field-based information into the model can help to improve the model accuracy.

关键词： Climate change Forest line Forest line advance Hybrid cartographic model Makalu Barun National Park

Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： parveen kumar Satish kumar Sharma Ratnesh kumar Raj Singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 *** heat can be mitigated via air or water *** this study,the material was deposited under four different heat-input conditions with air or water *** air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water *** validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input *** the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were *** multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)*** microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition ***,water cooling was found to govern bead characteristics,such as wall width and *** grain size and anisotropy of the mechanical properties also decreased in the water-cooled ***,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)

Contemporary and Historic Population Structure of Abies spectabilis at Treeline in Barun Valley,Eastern Nepal Himalaya

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Journal of Mountain Science 2015年第3期12卷 558-570页

作者： parveen kumar CHHETRI David M.CAIRNS Department of Geography Texas A&M UniversityCollege Station

Treeline ecotone dynamics of Abies spectabilis （D. Don） Mirb. in the Barun valley, Makalu Barun National Park, eastern Nepal Himalaya were studied by establishing seven plots （20 m x variable length） from the foresfline to the tree species limit： three plots on the south- and north-facing slopes each （S1-S3, N1-N3）, and one plot on the east- facing slope （E） in the relatively undisturbed forests. A dendroecological method was used to study treeline advance rate and recruitment pattern. In all the plots, most trees established in the early 20th century, and establishment in the second half of the 20th century was confined to the foresfline area. Treeline position has not advanced substantially in the Barun valley, with 0nly 22 m average elevational shift in the last 13o years, and with average current shifting rate of 14 cm/yr. Moreover, no significant relationship was found between tree age and elevation on the south-, north-, and east-facing slopes. The number of seedlings and saplings in near the treeline area was negligible compared to that near the foresfline area. Therefore, A. spectabilis treeline response to the temperature change was slow, despite the increasing temperature trend in the region. Beside the temperature change, factors such as high inter-annual variability in temperature, dense shrub cover, and local topography also play an important role in treeline advance and controlling recruitment pattern above the treeline.

关键词： Climate change Treeline ecotone Treeline advance Recruitment pattern

Dendroclimatic response of Abies spectabilis at treeline ecotone of Barun Valley, eastern Nepal Himalaya

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Journal of Forestry Research 2016年第5期27卷 1163-1170页

作者： parveen kumar Chhetri David M.Cairns Department of Geography Texas A&M UniversityCollege StationTX 77843-3147USA

A dendroclimatic study was conducted in the treeline ecotone of Barun Valley, eastern Nepal, to determine the tree-ring climate response and ring width trend of Abies spectabilis. A 160-year-old chronology, from 1850 to 2010, was developed from 38 tree-ring samples. No higher growth in recent decades was observed in tree-ring width in this area. The mean temperature of the current year in February and in the combined winter months of December, January, and February showed significant positive correlation with tree-ring width, although no significant correlation was found between tree-ring width and the precipitation pattern of the region. This tree-ring climate response result is different from that in other studies in Nepal, which could be attributed to location and elevation.

关键词： spectabilis Dendroclimatology Treeline ecotone Abies Climate response Tree-ring width

Aspects of high-performance and bio-acceptable magnetic nanoparticles for biomedical application

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Asian Journal of Pharmaceutical Sciences 2021年第6期16卷 704-737页

作者： Preeti Kush parveen kumar Ranjit Singh Ajeet Kaushik School of Pharmacy Adarsh Vijendra Institute of Pharmaceutical SciencesShobhit University GangohSaharanpurUttar Pradesh 247341India Nanotechnology Division(H-1) CSIR-Central Scientific Instruments OrganizationChandigarh 160030India NanoBioTech Laboratory Health System EngineeringDepartment of Natural SciencesFlorida Polytechnic UniversityLakelandFL 33805-8531United States

This review covers extensively the synthesis&surface modification,characterization,and application of magnetic *** biomedical applications,consideration should be given to factors such as design strategies,the synthesis process,coating,and surface *** synthesis method regulates post-synthetic change and specific applications in vitro and in vivo imaging/diagnosis and pharmacotherapy/*** insights have been provided on biodistribution,pharmacokinetics,and toxicity in a living system,which is imperative for their wider application in *** nanoparticles can be decorated with multiple contrast agents and thus can also be used as a probe for multi-mode imaging or double/triple imaging,for example,MRI-CT,*** loading with different drug molecules/dye/fluorescent molecules and integration with other carriers have found application not only in locating these particles in vivo but simultaneously target drug delivery/hyperthermia inside the *** are underway to collect the potential of these magnetically driven nanoparticles in various scientific fields such as particle interaction,heat conduction,imaging,and ***,this comprehensive data will help in the further development of advanced techniques for theranostics based on high-performance magnetic nanoparticles and will lead this research area in a new sustainable direction.

关键词： Magnetism Synthesis Characterization Delivery Imaging Biodistribution Pharmacokinetic

Incidental finding of intra-abdominal hemangioma in an infant presenting with intestinal obstruction:a case report

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World Journal of Pediatric Surgery 2022年第1期5卷 55-57页

作者： parveen kumar Arti Khatri Somshankar Chowdhury Nidhi Mahajan Geetika Mathur Pediatric Surgery Chacha Nehru Bal ChikitsalayaNew DelhiIndia Pathology Chacha Nehru Bal ChikitsalayaNew DelhiIndia

Hemangiomas are the most common benign vascular tumours of the pediatric age *** originate from embryonic remnants of unipotent angioblastic *** liver is the most common site for hemangioma in the abdomen.1 The prevalence of hepatic hemangioma(HH)varies from 1%to 20%in the general popula-tion,and it is two to five times more common in *** is usually detected incidentally and shows no symptoms;therefore,most of the time it does not require any treatment.2 However,hemangioma may sometimes occur at the atypical location and present with unusual clinical manifestations within the abdominal *** to these reasons,it leads to diag-nostic confusion,resulting in their inadvertent surgical excision.12 We present here a case of intra-abdominal hemangioma in an infant who presented with the signs and symptoms of intestinal obstruction.

关键词： hemangioma infant abdominal

Biotransformation,multifunctional recycling mechanism of nanostructures,and evaluation of the safety of nanoscale materials

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Particuology 2023年第11期82卷 76-86页

作者： Debjyoti Talukdar parveen kumar Benu Chaudhary Deepak Sharma Nishant Yadav Obaid Afzal Abdulmalik Saleh Alfawaz Altamimi Waleed Hassan Almalki Sami IAlzarea Imran Kazmi Ashutosh Pareek Gaurav Gupta Madan Mohan Gupta Department of Medical Research Armenian Russian International University“Mkhitar Gosh”YerevanArmenia Shri Ram College of Pharmacy KarnalHaryanaIndia Guru Gobind Singh College of Pharmacy YamunanagarHaryanaIndia Department of Pharmaceutical Technology SOMSAdamas UniversityBarasat-Barracpore RoadKolkataWest BengalIndia B.S.Anangpuria Institute of Pharmacy FaridabadHaryanaIndia Department of Pharmaceutical Chemistry College of PharmacyPrince Sattam Bin Abdulaziz UniversityAl Kharj11942Saudi Arabia Department of Pharmacology College of PharmacyUmm Al-Qura UniversityMakkahSaudi Arabia Department of Pharmacology College of PharmacyJouf UniversitySakakaAl-JoufSaudi Arabia Department of Biochemistry Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia Department of Pharmacy Banasthali VidyapithBanasthali-RajasthanIndia School of Pharmacy Suresh Gyan Vihar UniversityJagatpura302017Mahal RoadJaipurIndia Department of Pharmacology Saveetha Dental CollegeSaveetha Institute of Medical and Technical SciencesSaveetha UniversityChennaiIndia Uttaranchal Institute of Pharmaceutical Sciences Uttaranchal UniversityDehradunIndia School of Pharmacy Faculty of Medical SciencesThe University of the West IndiesSt.AugustineTrinidad and Tobago

Current evidence of concept analyses recommending nanotechnology for biomedical uses abounds in recent research. The area of biotechnology interfaces with nanostructures, reconfigures their composition, and alters their characteristics;which influences the dispersion of the particles, the biotransformation they cause, and their potential toxic effect. It is vital to link the idea of the lifecycle of nanostructures to the biological impacts and use methodologies to identify, estimate, and track the gradual bioprocessing of nanostructures in vivo, from a body-wide level to a nanoscopic size. This is necessary because understanding how nanostructures processing, degradation, persistence, and recycling predict potential exposure risks. The safe implementation of nanotechnology-based products in biomedical applications necessitates an extensive understanding of the recycling and transformations of nanomaterials in a living organism. Long-term fate in the body is crucial, as it governs potential environmental risks to human health. Strategies may be used to manage the long-term outcome of nanostructures in an organism since, in addition to composition, their design also affects how long they last and how easily they degrade. The lifespan of nanoparticles, a flexible and biocompatible category of nanostructures that have made it into clinical trials, is the subject of this article. Strategies may be used to manage the long-term outcome of nanoparticles in an organism since, in addition to composition, their design also affects how long they last and how easily they degrade. This review explained the safety of nanoscale materials, biotransformation, and the multifunctional recycling mechanism of nanostructures.

关键词： Nanostructure Nanoparticle Biotransformation Toxiceffect Environmental risk

Comparison of Sensitivity and Specificity of ZN and Fluorescent Stain Microscopy with Culture as Gold Standard

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Journal of Tuberculosis Research 2017年第2期5卷 118-128页

作者： Rekha Bansal parveen kumar Sharma Subhash Chand Jaryal Puneet kumar Gupta Dinesh kumar Department of Pulmonary Medicine Dr. RP Government Medical College Kangra at Tanda (HP) India Department of Pharmacology SLBS Government Medical College Mandi at Nerchowk (HP) India Department of Microbiology SLBS Government Medical College Mandi at Nerchowk (HP) India Department of Microbiology All India Institute of Medical Sciences Rishikesh Uttarakhand India Department of Community Medicine Dr. RP Government Medical College Kangra at Tanda (HP) India

Introduction: Reports indicate that fluorescent staining of smears increases sensitivity of direct microscopy;so ZN staining is being replaced with fluorescent microscopy in RNTCP in India. Chemical processing and sputum concentration may also improve sensitivity of microscopy. Objective: To compare the sensitivity and specificity of microscopy for AFB using ZN and fluorescent stains in direct and concentrated specimen with culture as gold standard. Methods: Morning sputum specimen of patients, suspected of having pulmonary tuberculosis, over a period of 6 months was subjected to direct microscopy using fluorescent stain;the same slide was over-stained with ZN stain. Same sputum sample was concentrated by Petroff’s method and subjected to fluorescent microscopy followed by ZN microscopy and finally to culture for AFB. Results: Sensitivity of fluorescent stained concentrated sputum samples was maximum and of ZN stained unprocessed sputum samples was minimum. Specificity of three of the methods was equal at 0.96 but of ZN stained concentrated sputum smears was 0.97. Sensitivity of total fluorescent stains was 0.85 (Specificity 0.96) and sensitivity of total ZN stained smears was 0.80 (Specificity 0.96). Discussion: We used same smear for fluorescent and ZN stains, so smear related variability is decreased. Blinding for microscopy was practically complete. Conclusion: The sensitivity of sputum microscopy for AFB can be increased by concentrating the sputum and using fluorescent microscopy. The specificity remains high in all the methods.

关键词： Sensitivity and Specificity Microscopy for AFB ZN Staining Fluorescent Stain Concentration of Sputum

Adverse Drug Reactions in Patients on Second Line Anti-Tubercular Drugs for Drug Resistant Tuberculosis in Rural Tertiary Care Hospital in North India

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Journal of Tuberculosis Research 2018年第3期6卷 207-214页

作者： Anita kumari parveen kumar Sharma Dinesh Kansal Rekha Bansal Rajan Negi Department of Pharmacology Dr. YSP Government Medical College Nahan (HP) India Department of Pharmacology SLBS Government Medical College Mandi at Nerchowk (HP) India Department of Pharmacology Dr. RP Government Medical College Kangra at Tanda (HP) India Department of Pulmonary Medicine Dr. RP Government Medical College Kangra at Tanda (HP) India

Introduction: The adverse drug events (ADEs) to second-line anti-TB drugs are one of the major reasons for the patients default on treatment. A general awareness of various adverse drug events (ADE) and their management is essential for the effective management of tuberculosis. Identification of adverse drug reaction profile of patients can be useful for the early detection, management and prevention of adverse drug events. Material and methods: It was a prospective observational study conducted after approved Institutional Ethics Committee. A total of 104 drug resistant tuberculosis patients registered from 1st November 2012 to 31st October 2013 started with second line anti-tubercular drugs under PMDT-RNCP after taking written informed consent. Adverse drug reaction during treatment recorded and assessed by Hart wig and WHO scale. Results: 87% patients experienced adverse drug reactions. Total 346 ADR were reported. Most common were gastritis (65%) and arthralgia (60.6%), others were nausea (35.6%), vomiting (32.7%), hyperuricemia (30.8%), giddiness (27%), anorexia (17.3), generalized weakness (15.4), insomnia (10.6%), psychosis (8.6%), hearing impairment (6.7%), hypersensitivity reaction (5.8%), peripheral neuropathy (4.8%), visual disturbance (3.8%), nephrotoxicity (2.9%), forgetfulness (2.9%), gynaecomastia (1.9%), hypothyroidism (1%), seizure (1%), and thrombocytopenia (1%). Conclusion: Majority of patients experienced wide range adverse drug reactions. Most of patients faced the problem within 2 - 3 months of initiation of treatment and managed by symptomatic. Early identification, prompt management and standardized reporting adverse drug reactions at all the level of healthcare are needed.

关键词： Drug Resistant Tuberculosis ADR: Second line Anti-Tubercular Drugs

Observations on Traditional Phytotherapy among the Inhabitants of Lahaul Valley through Amchi System of Medicine—A Cold Desert Area of Himachal Pradesh in North Western Himalayas, India

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Chinese Medicine 2011年第3期2卷 93-102页

作者： parveen kumar Sharma Surender kumar Thakur S. Manuja R. K. Rana Pardeep kumar Sanjay Sharma Jagdish Chand Ashok Singh Krishan kumar Katoch 不详

The paper highlights the Phyto-diversity and indigenous uses an ecosystem existing in Lahaul Valley of tribal district of Lahaul and Spiti in Himacjhal Pradesh, India. This is one of the most preferred tourist spot especially for foreigners. The cold desert area of India is known for its specific topography, sense climate and unique vegetation. The valley is rich in high value medicinal wealth and local inhabitants (Buddhist) practice the Tebetan Amchi System of Medicine. Keeping in view the continuous pressure on nature, this paper reflects the Phyto-diversity of Valley, with reference to medicinal and aromatic plants and conserva-tion mechanisms to protect the valuable wealth of the valley and also suggests effective ecotourisim planning of the study area.

关键词： Diversity Medicinal and Aromatic Plants Ecotourisim Lahaul Valley Indigenous Uses Tebetan Amchi System of Medicine