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International Journal of Biomathematics 2019年第2期12卷 115-142页

作者： p.d.N.Srinivasu simon d.Zawka Sri Sathya Sai University for Human Excellence Navanihala Village Okali PostKamalapur Taluk Gulbarga DistrictKarnataka 585313India department of Mathematics Andhra University Visakhapatnam 530003India department of Mathematics Ar ba Minch University Arba MinchEthiopia

This work presents an optimal harvesting problem associated with a single-species population governed by Gompertz law in a seasonally fluctuating *** influence of environmental fluctuation is accommodated by choosing the coefficients in the differential equation to be periodic functions with the same period and restriction on the harvesting effort is accommodated by considering binding constraints on the control ***,a linear optimal control problem has been considered where the state dynamics is governed by Gompertz equation and the control variable is subject to the binding *** the help of maximum principle and the concept of blocked intervals,an optimal periodic solution has been obtained which is followed by the construe tion of optimal solution using the theory of most rapid *** results of the study are demonstrated through numerical simulations.

关键词： Optimal harvesting Gompertz equation seasonality binding constraint blocked intervals

Influence of interparticle interactions on the kinetics of self-assembly and mechanical strength of nanoparticulate aggregates

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particuology 2009年第2期7卷 106-113页

作者： Roberto Moreno-Atanasio simon J.Antony Richard A.williams Institute of particle Science and Engineering University of LeedsLeedsLS2 9JTUnited Kingdom

Computer simulations based on discrete Element Method have been performed in order to investigate the influence of interparticle interactions on the kinetics of self-assembly and the mechanical strength of nanoparticle aggregates. Three different systems have been considered. In the first system the interaction between particles has been simulated using the JKR （Johnson, Kendall and Roberts） contact theory, while in the second and third systems the interaction between particles has been simulated using van der Waals and electrostatic forces respectively. In order to compare the mechanical behaviour of the three systems, the magnitude of the maximum attractive force between particles has been kept the same in all cases. However, the relationship between force and separation distance differs from case to case and thus, the range of the interparticle force. The results clearly indicate that as the range of the interparticle force increases, the self-assembly process is faster and the work required to produce the mechanical failure of the assemblies increases by more than one order of magnitude.

关键词： Nanoparticles discrete Element Method (dEM) Self-assembly JKR model van der Waals force

Rangeland hillslope lengths:A case study at the Walnut Gulch Experimental Watershed,southeastern Arizona

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International Soil and Water Conservation Research 2022年第4期10卷 597-609页

作者： Li Li Mark A.Nearing philip Heilman Mary H.Nichols d.p.Guertin C.J.williams School of Natural Resources and the Environment University of ArizonaTucsonAZ85705USA USdA-Agricultural Research Service Southwest Watershed Research CenterTucsonAZ85719USA

Rangeland hillslopes provide much of the sediment supplied to channel systems and their lengths exert a fundamental constraint on hillslope diffusive ***,information regarding lengths of rangeland hillslopes,and how best to estimate them,is *** this study,three groups of watersheds(10 in total)were selected from the Walnut Gulch Experimental Watershed according to their geology,soil and vegetation *** 1 watersheds were at lower elevations dominated by shrubs,Group 3 were at high elevations dominated by grass,and Group 2 were mixed shrub and *** hillslope lengths were calculated from 1 m-resolution dEMs using three methods:a flow routing algorithm,slope-area relationships,and inverted relationship with drainage *** that characterize the current watersheds,including Hack's exponent and coefficient,watershed shape coefficient,channel concavity and steepness,and surface roughness,were quantified and related to hillslope *** shows:(1)estimated hillslope lengths were different for the three methods and between the three groups of watersheds;(2)hillslope lengths that measured from the flow routing algorithm for the ten selected watersheds primarily ranged from 30 to 100 m,with a median value of 63.0 m,which was 20%e50%greater than those derived from slope-area plots or drainage densities;(3)hillslope lengths estimated from the flow routing method were greater in Group 3 watersheds than in Group 2 and then in Group 1 *** attributed these differences in hillslope lengths to the historic epeirogenic pulses,watershed and drainage network morphology,and differences in vegetation characteristics;(4)measured hillslope lengths from the flow routing algorithm were best correlated with hillslope relief,then surface roughness,channel steepness and *** results would benefit the applications of hydrological and erosion models in rangelands.

关键词： Rangeland hillslope Slope length drainage density Slope-area relationship Hillslope hydrology

NMR double resonance study of azide binding to cytochrome c

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Chinese Journal of Chemistry 1992年第1期10卷 40-44页

作者： CONCAR d. MOORE G.R. williams R.J.p. Inorganic Chemistry Laboratory University of OxfordUK

Equilibrium constants for the binding of azide to ferri-cytochrome c at temperature range of 305—325 K were determined at pH=7 by using ~1H double resonance *** values(⊿H^o=-34.5 kJ/mol,⊿S^o=-100 J/mol)were obtained from van't Hoff's relation and were compared with those for azide binding to other ferric *** reason of lower affinity of cytochrome c for azide was discussed.

关键词： NMR double resonance study of azide binding to cytochrome c

Urinary nuclear magnetic resonance spectroscopy of a Bangladeshi cohort with hepatitis-B hepatocellular carcinoma: A biomarker corroboration study

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World Journal of Gastroenterology 2016年第16期22卷 4191-4200页

作者： I Jane Cox Abil E Aliev Mary ME Crossey Mahvish dawood Mamun Al-Mahtab Sheikh M Akbar Salimur Rahman Antonio Riva Roger williams simon d Taylor-Robinson Institute of Hepatology London Foundation for Liver Research department of Chemistry University College London division of digestive diseases Department of Surgery and Cancer Imperial College London department of Hepatology Bangabandhu Sheikh Mujib Medical University department of Medical Sciences Toshiba General Hospital

AIM: To establish if a distinct urinary metabolic profile could be identified in Bangladeshi hepatitis-B hepatocellular carcinoma (HCC) patients compared to cirrhosis patients and ***: Urine samples from 42 Bangladeshi patients with HCC (39 patients with hepatitis-B HCC), 47 with cirrhosis on a background of hepatitis B, 46 with chronic hepatitis B, and seven ethnically-matched healthy controls were analyzed using nuclear magnetic resonance (NMR) spectroscopy. A full dietary and medication history was recorded for each subject. The urinary NMR data were analyzed using principal component analysis (pCA) and orthogonal partial least squared discriminant analysis (OpLS-dA) techniques. differences in relative signal levels of the most discriminatory metabolites identified by pCA and OpLS-dA were compared between subject groups using an independent samples Kruskal-Wallis one-way analysis of variance (ANOVA) test with all pairwise multiple comparisons. Within the patient subgroups, the Mann-Whitney U test was used to compare metabolite levels depending on hepatitis B e-antigen (HBeAg) status and treatment with anti-viral therapy. A Benjamini-Hochberg adjustment was applied to acquire the level of significance for multiple testing, with a declared level of statistical significance of p differences in age (p p d body mass index (p ps. Serum alanine aminotransferase (ALT) was significantly higher in the HCC group compared to controls (p protein was generally markedly elevated in HCC compared to controls; and serum creatinine levels were significantly reduced in the HCC group compared to the cirrhosis group (p = 0.004). A three-factor pCA scores plot showed clustering of the urinary NMR spectra from the four subgroups. Metabolites that contributed to the discrimination between the subgr

关键词： Urinary metabolic profiling Hepatocellular carcinoma Nuclear magnetic resonance spectroscopy Hepatitis B Bangladesh

Syntheses,structures,and reactivity of ruthenium(Ⅱ) hydride complexes containing Klui's oxygen tripodal ligand

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Science China Chemistry 2010年第10期53卷 2139-2143页

作者： NG Ho-Yuen LAI Chun-Sing williams Ian d. LEUNG Wa-Hung department of Chemistry The Hong Kong University of Science and Technology

Treatment of Ru(CO)(Cl)(H)(pph3)3 with NaLOEt (LOEt-= [CpCo{p(O)(OEt)2}3]-) afforded the hydride complex (pph3)(CO)-LOEtRu(H) (1), which has been characterized by X-ray crystallography. Similarly, the tricyclohexylphosphine analogue, (pCy3)(CO)LOEtRu(H) (2), was synthesized from Ru(CO)Cl(H)(pCy3)2 and NaLOEt. Treatment of complex 1 with R'SO2N3 afforded the (arylsulfonyl)amido complexes LOEtRu(CO)(pph3)(NHSO2R) (R = 2,4,6-i-pr3C6H2 (3), 4-t-BuC6H4 (4)). The crystal structure of complex 3 has been determined. The Ru-N distance and Ru-N-S angle in 3 are 2.076(3) and 126.14(16)°, respectively. Reactions of complex 1 with acids have been studied.

关键词： ruthenium oxygen tripodal ligand hydride complex (arylsulfonyl)amido complex

Higher infliximab and adalimumab trough levels are associated with fistula healing in patients with fistulising perianal Crohn’s disease

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World Journal of Gastroenterology 2022年第23期28卷 2597-2608页

作者： Bonita Gu Kavya Venkatesh Astrid-Jane williams Watson Ng Crispin Corte Ali Gholamrezaei simon Ghaly Wei Xuan Sudarshan paramsothy Susan Connor South Western Sydney Clinical School University of New South WalesSydney 2170New South WalesAustralia department of Gastroenterology and Hepatology Liverpool HospitalSydney 2170New South WalesAustralia AW Morrow Gastroenterology and Liver Centre Royal Prince Alfred HospitalSydney 2050New South WalesAustralia department of Medicine University of NewcastleNewcastle 2308New South WalesAustralia Central Clinical School University of SydneySydney 2050New South WalesAustralia Ingham Institute of Applied Medical Research Sydney 2170New South WalesAustralia department of Gastroenterology St Vincent’s Hospital SydneySydney 2010New South WalesAustralia St Vincent’s Clinical School University of New South WalesSydney 2010New South WalesAustralia department of Gastroenterology and Hepatology Concord Repatriation General HospitalSydney 2139New South WalesAustralia Concord Clinical School University of SydneySydney 2139New South WalesAustralia

BACKGROUNd Tumor necrosis factor-alpha inhibitors,including infliximab and adalimumab,are effective medical treatments for perianal fistulising Crohn’s disease(Cd),but not all patients achieve fistula *** To determine the correlation between perianal fistula healing and closure with infliximab and adalimumab trough *** In this multicentre retrospective study conducted across four tertiary inflammatory bowel disease centres in Australia,we identified Cd patients with perianal fistulae on maintenance infliximab or adalimumab who had a trough level within twelve weeks of clinical *** collected included demographics,serum infliximab and adalimumab trough levels(mg/L)within 12 wk before or after their most recent clinical assessment and concomitant medical or surgical *** primary outcome was fistula healing,defined as cessation in fistula *** secondary outcome was fistula closure,defined as healing and closure of all external fistula *** between patients who did or did not achieve fistula healing were compared using the chi-square test,t test or Mann-Whitney U *** One hundred and fourteen patients(66 infliximab,48 adalimumab)were ***-eight(72.7%)patients on maintenance infliximab achieved fistula healing and 18(27.3%)achieved fistula ***-seven(77%)patients on maintenance adalimumab achieved fistula healing and 17(35.4%)achieved fistula *** who achieved fistula healing had significantly higher infliximab and adalimumab trough levels than patients who did not[infliximab:6.4(3.8-9.5)vs 3.0(0.3-6.2)mg/L,p=0.003;adalimumab:9.2(6.5-12.0)vs 5.4(2.5-8.3)mg/L,p=0.004].For patients on infliximab,fistula healing was associated with lower rates of detectable anti-infliximab antibodies and younger *** patients on adalimumab,fistula healing was associated with higher rates of combination therapy with an *** trough levels for patients with and without fistu

关键词： Crohn’s disease perianal disorders Biologics Inflammatory bowel disease

Real-world performance analysis of a novel computational method in the precision oncology of pediatric tumors

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World Journal of pediatrics 2023年第10期19卷 992-1008页

作者： Barbara Vodicska Júlia déri dóra Tihanyi Edit Várkondi EnikőKispéter Róbert dóczi dóra Lakatos Anna dirner Mátyás Vidermann péter Filotás Réka Szalkai-dénes István Szegedi Katalin Bartyik Krisztina Míta Gábor Réka simon péter Hauser György péter Csongor Kiss Miklós Garami István peták Oncompass Medicine Hungary Kft Retek Str.34Budapest 1024Hungary division of pediatric Hematology-Oncology Department of PediatricsFaculty of MedicineUniversity of DebrecenDebrecenHungary department of pediatrics Albert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Onco-Hematology department Velkey LászlóPaediatric Health CentreMiskolcHungary department of paediatrics Semmelweis UniversityBudapestHungary Onco-Hematology department Heim Pál Children’s HospitalBudapestHungary department of pharmacology and pharmacotherapy Semmelweis UniversityBudapestHungary department of pharmaceutical Sciences University of Illinois at ChicagoChicagoUSA Genomate Health CambridgeMAUSA

Background The utility of routine extensive molecular profiling of pediatric tumors is a matter of debate due to the high number of genetic alterations of unknown significance or low evidence and the lack of standardized and personalized decision support *** drug assignment(ddA)is a novel computational method to prioritize treatment options by aggregating numerous evidence-based associations between multiple drivers,targets,and targeted *** has been validated to improve personalized treatment decisions based on the outcome data of adult patients treated in the SHIVA01 clinical *** aim of this study was to evaluate the utility of ddA in pediatric *** Between 2017 and 2020,103 high-risk pediatric cancer patients(d in our precision oncology program,and samples from 100 patients were eligible for further *** or blood samples were analyzed by whole-exome(WES)or targeted panel sequencing and other molecular diagnostic modalities and processed by a software system using the ddA algorithm for therapeutic decision ***,a molecular tumor board(MTB)evaluated the results to provide therapy *** Of the 100 cases with comprehensive molecular diagnostic data,88 yielded WES and 12 panel sequencing *** identified matching off-label targeted treatment options(actionability)in 72/100 cases(72%),while 57/100(57%)showed potential drug *** reached 88%(29/33)by 2020 due to the continuous updates of the evidence *** approved the clinical use of a ddA-top-listed treatment in 56 of 72 actionable cases(78%).The approved therapies had significantly higher aggregated evidence levels(AELs)than dismissed *** of WES results for targeted panels missed important mutations affecting therapy *** ddA is a promising approach to overcome challenges associated with the interpretation of extensive molecular profiling in the routine car

关键词： Computational decision support pediatric tumors precision oncology Tumor board

Aging impairs the osteocytic regulation of collagen integrity and bone quality

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Bone Research 2024年第1期12卷 78-94页

作者： Charles A.Schurman Serra Kaya Neha dole Nadja M.Maldonado Luna Natalia Castillo Ryan potter Jacob p.Rose Joanna Bons Christina d.King Jordan B.Burton Birgit Schilling simon Melov simon Tang Eric Schaible Tamara Alliston department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC Berkeley/UCSF Graduate program in Bioengineering San FranciscoCA 94143USA Buck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

poor bone quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by *** hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(pLR),which maintains bone material *** examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged bone displayed decreased TGFβsignaling and pLR,but aging did not worsen the existing pLR suppression in male TβRII^(ocy−/−)*** relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity