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Microbial Biomass C,N and P in Disturbed Dry Tropical Forest Soils,India

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Pedosphere 2010年第6期20卷 780-788页

作者： j.S.SINGH D.P.SINGH A.k.kashyap Department of Environmental Science Babasaheb Bhimrao Ambedkar University Department of Botany Banaras Hindu University

Variations in microbial biomass C (MB-C),N (MB-N) and P (MB-P) along a gradient of different dominant vegeta- tion covers (natural forest,mixed deciduous forest,disturbed savanna and grassland ecosystems) in dry tropical soils of Vindhyan Plateau,India were studied from january 2005 to December *** water holding capacity,organic C,total N,total P and soil moisture content were comparatively higher in forest soils than in the savanna and grassland *** different study sites the mean annual MB-C,MB-N and MB-P at 0-15 cm soil depth varied from 312.05 ± 4.22 to 653.40 ± 3.17,32.16 ± 6.25 to 75.66 ± 7.21 and 18.94 ± 2.94 to 30.83 ± 23.08 μg g ?1 dry soil,*** all the investigated sites,the maximum MB-C,MB-N and MB-P occurred during the dry period (summer season) and the minimum in wet period (rainy season).In the present study,soil MB-C,MB-N and MB-P were higher at the forest sites compared to savanna and grassland *** differences in MB-C,MB-N and MB-P were significant (P mixed deciduous forest > savanna > *** results suggested that deforestation and land use practices (conversion of forest into savanna and grassland) caused the alterations in soil properties,which as a consequence,led to reduction in soil nutrients and MB-C,MB-N and MB-P in the soil of disturbed sites (grassland and savanna) compared to undisturbed forest ecosystems.

关键词： deciduous forest grassland savanna soil moisture vegetation

Photonic properties of novel Yb3＋ doped germanium-lead oxyfluoride glass-ceramics for laser cooling applications

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Frontiers of Optoelectronics 2018年第2期11卷 189-198页

作者： Lauro j. Q. MAIA jyothis THOMAS Yannick LEDEMI kummara V. kRISHNAIAH Denis SELETSkIY Younes MESSADDEQ Raman kashyap Instituto de Fisica Universidade Federal de Goias Av. Esperanga 1533 Campus Samambaia Goiania GO 74690-900 Brazil Department of Electrical Engineering Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada Department of Engineering Physics Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada Centre d'Optique Photonique et Laser 2375 Rue de la Terrasse Universite Laval Qurbec QC G1V 0A6 Canada

Abstract In recent years, our research group has developed and studied new rare-earth doped materials for the promising technology of solid-state laser cooling, which is based on anti-stokes fluorescence. To the best of our knowledge, our group is the only one in Canada leading the research into the properties of nanoparticles, glasses and glass-ceramics for optical refrigeration appli- cations. In the present work, optical properties of 50GeO2- 30PbF2-18PbO-2YbF3 glass-ceramics for laser cooling are presented and discussed as a function of crystallization temperature. Spectroscopic results show that samples have near infrared photoluminescence emission due to the 2F5/2 - 2F7/2 Yb3＋ transition, centered at -1016 nm with an excitation wavelength of 920 nm or 1011 nm, and the highest photoluminescence emission efficiency occurs for heat-treatment for 5 h at 350℃. The internal photolumi- nescence quantum yield varies between 99% and 80%, depending on the temperature of heat-treatment, being the most efficient under 1011 nm excitation. The 2F5/2 lifetime increases from 1.472 to 1.970 ms for heat treatments at 330℃ to 350℃, respectively, due to energy trapping and the low phonon energy of the nanocrystals. The sample temperature dependence was measured with a fiber Bragg grating sensor, as a function of input pump laser wavelength and processing temperature. These measure- ments show that the heating process approaches near zero for an excitation wavelength between 1020 and 1030 nm, which is an indication that phonons are removed effectivelly from the glass-ceramic materials, and they can be used for optical laser cooling applications. On theother hand, the temperature increase as a function of input laser power into samples remains constant between 920 and 980 nm wavelength excitation, a temperature variation of 36 k/W （temperature of 58℃/W） was attained under excitation at 950 nm, showing a possible use for biomedical applications to be explored.

关键词： optical refrigeration oxyfluoride glass-cera-mics Yb3+ doping quantum yield infrared emission lifetime

Machine learning in data abstraction: A computable phenotype for sepsis and septic shock diagnosis in the intensive care unit

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World journal of Critical Care Medicine 2019年第7期8卷 120-126页

作者： Prabij Dhungana Laura Piccolo Serafim Arnaldo Lopez Ruiz Danette Bruns Timothy j Weister Nathan jerome Smischney Rahul kashyap Department of Anesthesiology and Perioperative Medicine Mayo ClinicRochesterMN 55905United States Multidisciplinary Epidemiology and Translational Research in Intensive Care Mayo ClinicRochesterMN 55905United States Department of Medicine Division of Pulmonary and Critical Care MedicineMayo ClinicRochesterMN 55905United States Anesthesia Clinical Research Unit Mayo ClinicMN 55905United States

BACkGROUND With the recent change in the definition(Sepsis-3 Definition)of sepsis and septic shock,an electronic search algorithm was required to identify the cases for data *** supervised machine learning method would help screen a large amount of electronic medical records(EMR)for efficient research *** To develop and validate a computable phenotype via supervised machine learning method for retrospectively identifying sepsis and septic shock in critical care *** A supervised machine learning method was developed based on culture orders,Sequential Organ Failure Assessment(SOFA)scores,serum lactate levels and vasopressor use in the intensive care units(ICUs).The computable phenotype was derived from a retrospective analysis of a random cohort of 100 patients admitted to the medical *** was then validated in an independent cohort of 100 *** compared the results from computable phenotype to a gold standard by manual review of EMR by 2 blinded *** was resolved by a critical care clinician.A SOFA score≥2 during the ICU stay with a culture 72 h before or after the time of admission was *** versions as V1 was defined as blood cultures with SOFA≥2 and Sepsis V2 was defined as any culture with SOFA score≥2.A serum lactate level≥2 mmol/L from 24 h before admission till their stay in the ICU and vasopressor use with Sepsis-1 and-2 were identified as Septic Shock-V1 and-V2 *** In the derivation subset of 100 random patients,the final machine learning strategy achieved a sensitivity-specificity of 100%and 84%for Sepsis-1,100%and 95%for Sepsis-2,78%and 80%for Septic Shock-1,and 80%and 90%for Septic *** overall percent of agreement between two blinded reviewers had a k=0.86 and 0.90 for Sepsis 2 and Septic shock 2 *** validation of the algorithm through a separate 100 random patient subset,the reported sensitivity and specificity for all 4 diagnoses were 100%-100%e

关键词： Machine learning Computable phenotype Critical care Sepsis Septic shock

Photonic properties of novel Yb3+ doped germanium-lead oxyfluoride glass-ceramics for laser cooling applications

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Frontiers of Optoelectronics 2018年第02期 189-198页

作者： Lauro june Queiroz Maia jyothis THOMAS Yannick LEDEMI kummara Venkata krishnaiah Denis SELETSkIY Younès MESSADDEQ Raman kashyap Instituto de Física Universidade Federal de Goiás Department of Electrical Engineering école Polytechnique de Montréal Department of Engineering Physics école Polytechnique de Montréal Centre d'Optique Photonique et Laser

In recent years, our research group has developed and studied new rare-earth doped materials for the promising technology of solid-state laser cooling,which is based on anti-stokes fluorescence. To the best of our knowledge, our group is the only one in Canada leading the research into the properties of nanoparticles,glasses and glass-ceramics for optical refrigeration applications. In the present work, optical properties of 50GeO2-30PbF2-18Pb O-2YbF3glass-ceramics for laser cooling are presented and discussed as a function of crystallization temperature. Spectroscopic results show that samples have near infrared photoluminescence emission due to the2F5/2–2F7/2Yb3+transition, centered at ～1016 nm with an excitation wavelength of 920 nm or 1011 nm, and the highest photoluminescence emission efficiency occurs for heat-treatment for 5 h at 350°C. The internal photoluminescence quantum yield varies between 99% and 80%,depending on the temperature of heat-treatment, being the most efficient under 1011 nm excitation. The2F5/2lifetime increases from 1.472 to 1.970 ms for heat treatments at 330°C to 350°C, respectively, due to energy trapping and the low phonon energy of the nanocrystals. The sample temperature dependence was measured with a fiber Bragg grating sensor, as a function of input pump laser wavelength and processing temperature. These measurements show that the heating process approaches near zero for an excitation wavelength between 1020 and 1030 nm,which is an indication that phonons are removed effectivelly from the glass-ceramic materials, and they can be used for optical laser cooling applications. On the other hand, the temperature increase as a function of input laser power into samples remains constant between 920and 980 nm wavelength excitation, a temperature variation of 36 k/W（temperature of 58°C/W） was attained under excitation at 950 nm, showing a possible use for biomedical applications to be explored.

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Predicting responses to platin chemotherapy agents with biochemically-inspired machine learning

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Signal Transduction and Targeted Therapy 2019年第1期4卷 636-647页

作者： Eliseos j.Mucaki jonathan Z.L.Zhao Daniel j.Lizotte Peter k.Rogan Department of Biochemistry Schulich School of Medicine and DentistryWestern UniversityLondonON N6A 2C1Canada Department of Computer Science Faculty of ScienceWestern UniversityLondonON N6A 2C1Canada Department of Epidemiology&Biostatistics Schulich School of Medicine and DentistryWestern UniversityLondonON N6A 2C1Canada Cytognomix Inc.LondonON N5X 3X5Canada Department of Oncology Schulich School of Medicine and DentistryWestern UniversityLondonON N6A 2C1Canada

The selection of effective genes that accurately predict chemotherapy responses might improve cancer *** compare optimized gene signatures for cisplatin,carboplatin,and oxaliplatin responses in the same cell lines and validate each signature using data from patients with *** support vector machine learning is used to derive gene sets whose expression is related to the cell line GI 50 values by backwards feature selection with *** genes and functional pathways distinguishing sensitive from resistant cell lines are identified by contrasting signatures obtained at extreme and median GI 50 *** of gene signatures at different thresholds are combined to reduce the dependence on specific GI 50 values for predicting drug *** most accurate gene signatures for each platin are:cisplatin:BARD1,BCL2,BCL2L1,CDkN2C,FAAP24,FEN1,MAP3k1,MAPk13,MAPk3,NFkB1,NFkB2,SLC22A5,SLC31A2,TLR4,and TWIST1;carboplatin:AkT1,EIF3k,ERCC1,GNGT1,GSR,MTHFR,NEDD4L,NLRP1,NRAS,RAF1,SGk1,TIGD1,TP53,VEGFB,and VEGFC;and oxaliplatin:BRAF,FCGR2A,IGF1,MSH2,NAGk,NFE2L2,NQO1,pank3,SLC47A1,SLCO1B1,and *** from The Cancer Genome Atlas(TCGA)patients with bladder,ovarian,and colorectal cancer were used to test the cisplatin,carboplatin,and oxaliplatin signatures,resulting in 71.0%,60.2%,and 54.5%accuracies in predicting disease recurrence and 59%,61%,and 72%accuracies in predicting remission,*** cisplatin signature predicted 100%of recurrence in non-smoking patients with bladder cancer(57%disease-free;N=19),and 79%recurrence in smokers(62%disease-free;N=35).This approach should be adaptable to other studies of chemotherapy responses,regardless of the drug or cancer types.

关键词： bladder chemotherapy signature

Association of latitude and altitude with adverse outcomes in patients with COVID-19: The VIRUS registry

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World journal of Critical Care Medicine 2022年第2期11卷 102-111页

作者： Aysun Tekin Shahraz Qamar Romil Singh Vikas Bansal Mayank Sharma Allison M LeMahieu Andrew C Hanson Phillip j Schulte Marija Bogojevic Neha Deo Simon Zec Diana j Valencia Morales katherine A Belden Smith F Heavner Margit kaufman Sreekanth Cheruku Valerie C Danesh Valerie M Banner-Goodspeed Catherine A St Hill Amy B Christie Syed A khan Lynn Retford karen Boman Vishakha kkumar john C O'Horo juan Pablo Domecq Allan j Walkey Ognjen Gajic Rahul kashyap Salim Surani TheSociety of Critical Care Medicine(SCCM)Discovery Viral Infection and Respiratory Illness Universal Study(VIRUS):COVID-Registry Investigator Group Department of Anesthesiology Mayo ClinicRochesterMN 55905United States Post-baccalaureate Research Education Program Mayo Clinic College of Medicine and ScienceRochesterMN 55905United States Division of Pulmonary and Critical Care Medicine Department of Internal MedicineMayo ClinicRochesterMN 55905United States Division of Clinical Trials and Biostatistics Department of Quantitative Health SciencesMayo ClinicRochesterMN 55905United States Alix School of Medicine Mayo ClinicRochesterMN 55905United States Division of Infectious Diseases Thomas Jefferson University HospitalPhiladelphiaPA 19107United States Prisma Health GreenvilleSC 29605United States Englewood Health EnglewoodNJ 07631United States Divisions of Cardiothoracic Anesthesiology and Critical Care Medicine Department of Anesthesiology and Pain ManagementUT Southwestern Medical CenterDallasTX 75390United States Center for Applied Health Research Baylor Scott and White HealthDallasTX 75246United States Department of Anesthesiology Critical Care and Pain MedicineBeth Israel Deaconess Medical CenterBostonMA 02215United States Allina Health MinneapolisMN 55407United States Department of Critical Care Atrium Health NavicentMaconGA 31201United States Division of Critical Care Medicine Mayo Clinic Health SystemMankatoMN 56001United States Society of Critical Care Medicine Mount ProspectIL 60056United States Division of Infectious Diseases Mayo ClinicRochesterMN 55905United States Division of Nephrology and Hypertension Department of Internal MedicineMayo ClinicRochesterMN 55905United States Pulmonary Center Division of PulmonaryAllergyCritical Care and Sleep MedicineDepartment of MedicineEvans Center of Implementation and Improvement SciencesBoston University School of MedicineBostonMA 02118United States Department of Pulmonary and Critical Care Medicine Texas A&M UniversityBryanTX 77807United States 不详

BACkGROUND The coronavirus disease 2019(COVID-19)course may be affected by environmental *** studies previously suggested a link between climatological factors and COVID-19 fatality ***,individual-level impact of these factors has not been thoroughly evaluated *** To study the association of climatological factors related to patient location with unfavorable outcomes in *** In this observational analysis of the Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study:COVID-19 Registry cohort,the latitudes and altitudes of hospitals were examined as a covariate for mortality within 28 d of admission and the length of hospital *** for baseline parameters and admission date,multivariable regression modeling was *** estimating equations were used to fit the *** Twenty-two thousand one hundred eight patients from over 20 countries were *** median age was 62(interquartile range:49-74)years,and 54%of the included patients were *** median age increased with increasing latitude as well as the frequency of ***,the percentage of comorbidities was lower in elevated *** within 28 d of hospital admission was found to be 25%.The median hospital-free days among all included patients was 20 *** the significant linear relationship between mortality and hospital-free days(adjusted odds ratio(aOR)=1.39(1.04,1.86),P=0.025 for mortality within 28 d of admission;aOR=-1.47(-2.60,-0.33),P=0.011 for hospital-free days),suggesting that adverse patient outcomes were more common in locations further away from the Equator;the results were no longer significant when adjusted for baseline differences(aOR=1.32(1.00,1.74),P=0.051 for 28-day mortality;aOR=-1.07(-2.13,-0.01),P=0.050 for hospital-free days).When we looked at the altitude’s effect,we discovered that it demonstrated a non-linear association with mortality wi

关键词： 28 d mortality Altitude COVID-19 Hospital-free days Latitude Outcomes