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Effects of in ovo delivered xylo-and mannan-oligosaccharides on growth performance,intestinal immunity,cecal short-chain fatty acids,and cecal microbiota of broilers

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Journal of Animal Science and Biotechnology 2022年第4期13卷 1099-1114页

作者： Amit kumar Singh Utsav Prakash tiwari Birendra Mishra Rajesh Jha Department of Human Nutrition Food and Animal SciencesUniversity of Hawaii at Manoa1955 East-West RdHonoluluHI 96822USA

Background:This study investigated a novel in ovo feeding strategy to determine the prebiotic effects of xylo-and mannan-oligosaccharides(XOS and MOS)differing in the degree of polymerization.A total of 192 fertilized eggs were divided into 6 treatment groups:i)normal saline control(NSC),ii)xylotriose(XOS3),iii)xylotetraose(XOS4),iv)mannotriose(MOS3),v)mannotetraose(MOS4),and vi)no injection control(NIC),each containing 4 replicate trays with 8 eggs per replicate.On d 17 of incubation,3 mg of oligosaccharides(except for controls)dissolved in 0.5 mL of 0.85%normal saline were injected into the amnion of Cobb 500 broilers eggs.After hatch,the chicks were raised for 28 d under standard husbandry practices and were fed a commercial broilers diet ad libitum,and samples were collected periodically.Results:The hatchability,growth performance,and relative weights of breast,drumstick,liver,and proventriculus were not different among the treatments(P>0.05).The XOS3 injection increased the total short-chain fatty acid production at d 28 compared with both control groups(P0.05).On the hatch day,the expression level of the CD3 gene(a T cell marker)was increased by XOS3,while the IL-10 gene(a marker of anti-inflammatory cytokine)was reduced by MOS4(P0.05),except XOS4 increased IL-4 compared with NSC(P<0.05).The broilers in the MOS4 group had higher operational taxonomic units(OTUs)and had more differentially abundant taxa,including order Lactobacillales and family Leuconostocaceae(P<0.05)than both controls on d 28.The predictive functional profiling indicated that the linoleic acid metabolism pathway was enriched in the cecal microbiota of the XOS3

关键词： Broilers Gut health Immunity in ovo Mannanoligosaccharides Microbiota Oligosaccharides Prebiotics Xylooligosaccharides

Dynamic analysis and identification of unbalance and misalignment in a rigid rotor with two offset discs levitated by active magnetic bearings:a novel trial misalignment approach

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Propulsion and Power Research 2021年第1期10卷 58-82页

作者： Prabhat kumar Rajiv tiwari Department of Mechanical Engineering Indian Institute of Technology GuwahatiGuwahatiAssam781039India

Rotating machinery is an essential and crucial component of numerous mechanical systems in modern industries,transport vehicles,and in several other applications.Excessive vibrations on rotating equipment due to multiple faults may cause catastrophic failure in machines and lead to hazardous accidents.So,there is a need for perceiving the dynamic nature and identifying the faults for the safe,smooth and effective operation of machines.This paper proposes a novel trial misalignment approach to estimate the misalignment with a similar concept as the trial unbalance in the rotor balancing.Active magnetic bearing(AMB)misalignment with the rotor has been investigated with residual misalignment and additional trial misalignment cases.Additional trial misalignments are provided in addition to the unknown misalignments of the residual misalignment case.For the execution of this methodology,the dynamic model of a four-degree-of-freedom unbalanced and misaligned rigid rotor with two offset discs supported by two active magnetic bearings has been mathematically developed.The offset discs result in the gyroscopic effect at high rotor speeds.Equations of motion of the rotor-AMB system have been derived and solved to generate the time domain rotor displacement and controlling current responses at AMB positions.A fast Fourier transform technique has been utilized to convert the time domain responses into the frequency domain for estimation of unbalance eccentricities and phases together with force-displacement and forcecurrent stiffnesses of misaligned AMBs as well as AMB's constant forces using the developed identification algorithm.Identified values of AMB's parameters for both residual and additional trial misalignment cases are evaluated to estimate the four unknown misalignments.Testing of the algorithm has also been carried out at multiple spin speeds against measurement signal noise in rotor responses and bias errors in rotor system parameters to check its effectiveness and robustness.The algorithm is found to be exhi

关键词： Misalignment Unbalance Active magnetic bearing Gyroscopic moment Fast Fourier transform Identification

Spectral narratives of microstructural restyling and their controls on hydrocarbon generation potential from coal

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International Journal of Coal Science & Technology 2023年第3期10卷 167-189页

作者： Tushar Adsul Santanu Ghosh Anwita Ojha Sudip Bhattacharyya atul kumar Varma Coal Geology and Organic Petrology Laboratory Department of Applied GeologyIndian Institute of Technology(Indian School of Mines)DhanbadJharkhand 826004India Department of Geology Mizoram UniversityAizawlMizoram 796004India Specialized Coal Petrography Laboratory Natural Energy ResourcesMission II-BGeological Survey of IndiaDK-6Sector-IlSalt Lake CityKolkataWest Bengal 700091India

The low to medium-rank Tertiary coals from Meghalaya,India,are explored for the first time for their comprehensive micro-structural characterization using the FTIR and Raman spectroscopy.Further,results from these coals are compared with the Permian medium and high-rank coals to understand the microstructural restyling during coalification and its controls on hydrocarbon generation.The coal samples are grouped based on the mean random vitrinite reflectance values to record the transformations in spectral attributes with increasing coal rank.The aliphatic carbon and the apparent aromaticity respond sharply to the first coalification jump(R:0.50%)during low to medium-rank transition and anchizonal metamorphism of the high-rank coals.Moreover,the Raman band intensity ratio changes during the first coalification jump but remains invari-able in the medium-rank coals and turns subtle again during the onset of pregraphitization in high-rank coals,revealing a polynomial trend with the coal metamorphism.The Rock-Eval hydrogen index and genetic potential also decline sharply at the first coalification jump.Besides,an attempt to comprehend the coal microstructural controls on the hydrocarbon poten-tial reveals that the Tertiary coals comprise highly reactive aliphatic functionalities in the type I-S kerogen,along with the low paleotemperature(74.59-112.28℃)may signify their potential to generate early-mature hydrocarbons.However,the presence of type II-II admixed kerogen,a lesser abundance of reactive moieties,and overall moderate paleotemperature(91.93-142.52℃)of the Permian medium-rank coals may imply their mixed hydrocarbon potential.Meanwhile,anchizonal metamorphism,polycondensed aromatic microstructure,and high values of paleotemperature(~334.25 to~366.79℃)of the high-rank coals indicate a negligible potential of producing any hydrocarbons.

关键词： Early mature oil generation Meghalaya high-sulfur coal Type II-S kerogen Microstructural ordering Coalification jump Hydrocarbon generation potential

Plant endemism in the Nepal Himalayas and phytogeographical implications

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Plant Diversity 2019年第3期41卷 174-182页

作者： Achyut tiwari Yadav Uprety Santosh kumar Rana Department of Botany Tri-Chandra Campus Tribhuvan University Kathmandu Nepal Central Department of Botany Tribhuvan University Kirtipur Kathmandu Nepal Research Centre for Applied Science and Technology Tribhuvan University Kathmandu Nepal IUCN (International Union for Conservation of Nature) Kathmandu Nepal Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 Yunnan China University of Chinese Academy of Sciences Beijing 100049 China

Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape.

关键词： Himalaya Topography Endemism

Review on the phosphate-based conversion coatings of magnesium and its alloys

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International Journal of Minerals,Metallurgy and Materials 2022年第7期29卷 1435-1452页

作者： Debasis Saran atul kumar Sivaiah Bathula David Klaumünzer Kisor K Sahu School of Minerals Metallurgical and Materials EngineeringIndian Institute of Technology BhubaneswarBhubaneswar 752050India Group Innovation(COI Battery-Metals) Volkswagen AGWolfsburg 38440Germany Virtual and Augmented Reality Centre of Excellence(VARCOE) Indian Institute of Technology BhubaneswarBhubaneswar 752050India

Magnesium(Mg)and its alloys are lightweight as well as biocompatible and possess a high strength-to-weight ratio,making them suitable for many industries,including aerospace,automobile,and medical.The major challenge is their high susceptibility to corrosion,thereby limiting their usability.The considerably lower reduction potential of Mg compared to other metals makes it vulnerable to galvanic coupling.The oxide layer on Mg offers little corrosion resistance because of its high porosity,inhomogeneity,and fragility.Chemical conversion coatings(CCs)belong to a distinct class because of underlying chemical reactions,which are fundamentally different from other types of coating.Typically,a CC acts as an intermediate sandwich layer between the base metal and an aesthetic paint.Although chromate CCs offer superior performance compared to phosphate CCs,yet still they release carcinogenic hexavalent chromium ions(Cr^(6+));therefore,their use is prohibited in most European nations under the Registration,Evaluation,Authorization and Restriction of Chemicals legislation framework.Phosphate-based CCs are a cost-effective and environment-friendly alternative.Accordingly,this review primarily focuses on different types of phosphate-based CCs,such as zinc,calcium,Mg,vanadium,manganese,and permanganate.It discusses their mechanisms,current status,pretreatment practices,and the influence of various parameters-such as pH,temperature,immersion time,and bath composition-on the coating performance.Some challenges associated with phosphate CCs and future research directions are also elaborated.

关键词： phosphate conversion coatings magnesium alloys corrosion zinc phosphate conversion coatings calcium phosphate conversion coatings magnesium phosphate conversion coatings

Estimation of the internal and external damping from the forward and backward spectrum of a rotor with a fatigue crack

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Propulsion and Power Research 2020年第1期9卷 62-74页

作者： Dipendra kumar Roy Rajiv tiwari Department of Mechanical Engineering Indian Institute of Technology GuwahatiAssam781039India Faculty of Mechanical Engineering Indian Institute of Technology GuwahatiAssam781039India

Both internal and external damping are concurrently present in a rotor system.However,the internal damping that originates from various sources often leads to instability in the rotor system,and hence its accurate estimation is crucial.The goal of the present paper is to distinctly estimate both external and internal damping in a Jeffcott rotor containing transverse crack.The modelling of the fatigue crack is based on the assumption of a switching crack,which additionally provides the internal damping due to rubbing on crack faces,which is hardly addressed in literature.Moreover,the fatigue crack leads to the forward and backward whirls due to asymmetry in the rotor.In the process of development of the identification procedure in the form of the regression equation for the estimation of internal damping,other important unknown rotor system parameters,like the external damping,unbalance and loss of stiffness of the shaft due to the crack,are also identified.This reduces the estimation error of the internal damping due to reduction in deviations of other model parameters.Numerically simulated responses are obtained from equations of motion of the rotor system in the form of a closed-form expression and by the Runge-Kutta integration method.The full-spectrum response data(both magnitude and phase)are utilized during the testing of the proposed identification procedure.Phase corrections have been incorporated in the full-spectrum.Measurement noise is added in numerical responses during identification of parameters to check the robustness of the algorithm and found to be working satisfactorily.

关键词： Internal damping External damping Switching crack Unbalance Full spectrum

Role of doxycycline in the treatment of dengue infection: An open-label, randomized, controlled, pilot trial

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Asian Pacific Journal of Tropical Medicine 2024年第4期17卷 160-165页

作者： Banothu Vinod kumar Kajal Kamboj Ashok kumar Pannu Ashok kumar Yadav Mandip Bhatia atul Saroch Department of Internal Medicine PGIMER ChandigarhIndia Department of Experimental Medicine&Biotechnology PGIMER ChandigarhIndia

Objective:To measure the effect of doxycycline on inflammatory marker[IL-6,TNF-α,ferritin and C reactive protein(CRP)]levels in patients with dengue infection.Methods:A single-centre,open-label,parallel-group randomized controlled trial was done in PGIMER Chandigarh from June 2021 to October 2022.Patients were randomized using a simple randomization process into two groups:the doxycycline treatment group(n=35)and the control group(n=34).Patients in the treatment group were given oral doxycycline 100 mg twice daily for five days along with standard treatment,whereas patients in the control group received only standard treatment.The objective was to measure the effect of doxycycline on inflammatory markers in dengue infection.Results:On comparative analysis at day 5,there was a statistically significant reduction in the median values of ferritin and CRP in cases compared to the control group(ferritin:P=0.006 and CRP:P=0.006).No significant reduction was noted in the levels of IL-6 and TNF-α.Conclusions:Doxycycline treatment led to a reduction of inflammatory markers in dengue infection.

关键词： Dengue Cytokine Doxycycline Serum ferritin C reactive protein

A prospective analysis of risk factors for pediatric burn mortality at a tertiary burn center in North India

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Burns & Trauma 2017年第3期5卷 199-208页

作者： Amol Dhopte Rahul Bamal Vinay kumar tiwari Department of Plastic Reconstructive and Maxillofacial surgery Government Medical College and Hospital Nagpur 440003 India Department of Burns Plastic and Maxillofacial Surgery VMMC&Safdarjung Hospital New Delhi India Department of Burns and Plastic Surgery PGIMER&RML Hospital New Delhi India

Background:None of the available mortality predicting models in pediatric burns precisely predicts outcomes in every population. Mortality rates as well as their risk factors vary with regions and among different centers within the regions. The aim of this study was to identify socio-demographic and clinical risk factors for mortality in pediatric burns in an effort to decrease the mortality in these patients. Methods:A prospective analytical study was conducted in patients up to the age of 18 years admitted for burn injuries in a tertiary care burn center in India from January to December 2014. Clinical and demographic data was col ected through questionnaire-interview and patient fol ow-up during their stay in the hospital. Univariate and multivariate firth logistic regression was used to identify various risk factors for mortality in pediatric burns. Results:A total of 475 patients were admitted during the study period. Overal mortality was 31.3%(n=149) in this study. Mean age of the patients who died was 8.68 years. Of the 149 deaths, 74 were males and 75 were females (male to female ratio=0.98). Mean total body surface area (TBSA) involved of the patients who expired was 62%. Inhalational injury was seen in 15.5%(n=74) of pediatric burn admissions. Mortality was significantly higher (74.3%) in patients with inhalation injury. Mortality was highest in patients with isolates of Acinetobacter + Klebsiella (58.3%), followed by Pseudomonas + Klebsiella (53.3%), Acinetobacter (31.5%), and Pseudomonas (26.3%) (p < 0.0005). Factors found to be significant on univariate firth analysis were older age, female gender, suicidal burns, higher TBSA, presence of inhalation injury, increased depth of burn, and positive microbial cultures. On multivariate analysis, higher TBSA was identified as an independent risk factor for mortality. The adjusted odds ratios for TBSA involvement was 21.706 (25.1-50%), 136.195 (50.1-75%), and 1019.436 (75.1-100%), respectively. Conclusion: TBSA is the most important factor predicting mortali

关键词： Pediatric burns Mortality Risk factors Microbiological cultures India

Masked Face Recognition Using MobileNet V2 with Transfer Learning

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Computer Systems Science & Engineering 2023年第4期45卷 293-309页

作者： Ratnesh kumar Shukla Arvind kumar tiwari Department of Computer Science&Engineering Dr.APJ Abdul Kalam Technical UniversityLucknow226021India Department of Computer Science&Engineering KNITSultanpur228118Uttar PradeshIndia

Corona virus(COVID-19)is once in a life time calamity that has resulted in thousands of deaths and security concerns.People are using face masks on a regular basis to protect themselves and to help reduce corona virus transmission.During the on-going coronavirus outbreak,one of the major priorities for researchers is to discover effective solution.As important parts of the face are obscured,face identification and verification becomes exceedingly difficult.The suggested method is a transfer learning using MobileNet V2 based technology that uses deep feature such as feature extraction and deep learning model,to identify the problem of face masked identification.In the first stage,we are applying face mask detector to identify the face mask.Then,the proposed approach is applying to the datasets from Canadian Institute for Advanced Research10(CIFAR10),Modified National Institute of Standards and Technology Database(MNIST),Real World Masked Face Recognition Database(RMFRD),and Stimulated Masked Face Recognition Database(SMFRD).The proposed model is achieving recognition accuracy 99.82%with proposed dataset.This article employs the four pre-programmed models VGG16,VGG19,ResNet50 and ResNet101.To extract the deep features of faces with VGG16 is achieving 99.30%accuracy,VGG19 is achieving 99.54%accuracy,ResNet50 is achieving 78.70%accuracy and ResNet101 is achieving 98.64%accuracy with own dataset.The comparative analysis shows,that our proposed model performs better result in all four previous existing models.The fundamental contribution of this study is to monitor with face mask and without face mask to decreases the pace of corona virus and to detect persons using wearing face masks.

关键词： Convolutional Neural Network(CNN) deep learning face recognition system COVID-19 dataset and machine learning based models