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Graphene 2017年第3期6卷 72-84页

作者： Thomas r. rybolt claire B. Black Department of Chemistry and Physics University of Tennessee at Chattanooga Chattanooga USA

Two-dimensional molecular recognition studies of the six polyaromatic hydro-carbons that can be formed from the combination of four benzene rings: tetracene, pyrene, 1,2-benzanthracene, 3,4-benzphenanthrene, triphenylene, and chrysene were explored for each of these six molecules interacting with six different graphene layer site-specific nanopores. Computational studies were done for the gas phase adsorption on single layer graphene, bilayer graphene, and six molecule-specific graphene bilayer nanopores. Molecular mechanics MM2 parameters have been shown previously to provide good comparisons to experimental adsorption energies for aromatic hydrocarbons adsorption on graphitic surfaces. These binding energies are dominated by van der Waals forces. Just as a jigsaw puzzle hole can accommodate only a specific piece, two-dimensional shape specific sites were created in the top layer of a graphene bilayer to match each one of the six adsorbate molecules. The purpose of this study was to examine the molecular recognition possibilities of site specific adsorption in these simple two-dimensional nanopores based on dispersion forces and molecular shape. For example, triphenylene has a calculated surface binding energy of 24.5 kcal/mol on the graphene bilayer and 30.2 kcal/mol in its own site specific pore. The interaction energy of this molecule in the other five sites ranged from 17.6 to 23.8 kcal/mol. All the molecules tetracene, pyrene, 1,2-benzanthracene, triphenylene and chrysene had higher binding energies in their matched molecule bilayer sites than on either single or double layer graphene. In addition, each one of these five molecules had a stronger binding in their own shape specific (puzzle-ene) site than any of the other molecular sites. The results suggest that two-dimensional molecular recognition based on shape specific pores may allow selectivity useful for applications such as sensors, separations, nanofabrication, or information storage.

关键词： Molecule-Graphene Interaction Molecular Mechanics Adsorption Energy Binding Energy on Graphene Polycyclic Aromatic Hydrocarbons Two-Dimensional Molecular recognition

The potential of self-supervised networks for random noise suppression in seismic data

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Artificial Intelligence in Geosciences 2021年第1期2卷 47-59页

作者： claire Birnie Matteo ravasi Sixiu Liu Tariq Alkhalifah King Abdullah University of Science and Technology ThuwalSaudi Arabia

Noise suppression is an essential step in many seismic processing workflows.A portion of this noise,particularly in land datasets,presents itself as random *** recent years,neural networks have been successfully used to denoise seismic data in a supervised ***,supervised learning always comes with the often unachievable requirement of having noisy-clean data pairs for *** blind-spot networks,we redefine the denoising task as a self-supervised procedure where the network uses the surrounding noisy samples to estimate the noise-free value of a central *** on the assumption that noise is statistically independent between samples,the network struggles to predict the noise component of the sample due to its randomicity,whilst the signal component is accurately predicted due to its spatio-temporal *** on synthetic examples,the blind-spot network is shown to be an efficient denoiser of seismic data contaminated by random noise with minimal damage to the signal;therefore,providing improvements in both the image domain and down-the-line tasks,such as post-stack *** conclude our study,the suggested approach is applied to field data and the results are compared with two commonly used random denoising techniques:FX-deconvolution and sparsity-promoting inversion by Curvelet *** demonstrating that blind-spot networks are an efficient suppressor of random noise,we believe this is just the beginning of utilising self-supervised learning in seismic applications.

关键词： Machine learning Noise suppression Self-supervised learning

Liver transplantation for hepatocellular carcinoma： is zero recurrence theoretically possible？

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Hepatobiliary & Pancreatic Diseases International 2016年第2期15卷 147-151页

作者： Sabine Irtan Louise Barbier claire Francoz Federica Dondéro Francois Durand Jacques Belghiti Department of Hepato-Pancreato-Biliary Surgery Beaujon HospitalAssistance Publique Hopitaux de ParisUniversity Denis Diderot-ParisⅦClichyFrance Department of Hepatology Beaujon HospitalAssistance Publique Hopitaux de ParisUniversity Denis Diderot-ParisⅦClichyFrance

BACKGrOUND： Hepatocellular carcinoma（HCC） recurrence remains a key issue after liver transplantation. This study aimed to determine a subgroup of HCC patients within the Milan criteria who could achieve a theoretical goal of zero recurrence rates after liver ***： Between 1999 and 2009, 179 patients who received liver transplantation for HCC within the Milan criteria were retrospectively included. Analysis of the factors associated with HCC recurrence was performed to determine the subgroup of patients at the lowest risk of ***： Seventy-two percent of the patients received a bridging therapy, including 54 liver resections. Eleven（6.1%） patients recurred within a delay of 19±22 months and ultimately died. Factors associated with recurrence were serum alpha-fetoprotein level 〉400 ng/m L, satellite nodules, poor differentiation, microvascular invasion and cholangiocarcinoma component. recurrence rates decreased from 6.1% to 3.1% in patients without any of these ***： Among HCC patients within the Milan criteria, selecting patients with factors based on histology would allow tending towards zero recurrence, and prior histological assessment by liver biopsy or resection may be essential to rule out poorly differentiated tumors, microvascular invasion,and cholangiocarcinoma component.

关键词： hepatocellular carcinoma liver transplantation neoplasm recurrence survival rate

Effect of non-enzymatic glycation on collagen nanoscale mechanisms in diabetic and age-related bone fragility

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BIOCELL 2023年第7期47卷 1651-1659页

作者： JAMES LrOSENBErG WILLIAM WOOLLEY IHSAN ELNUNU JULIA KAMML DAVID SKAMMEr claire ACEVEDO Department of Mechanical Engineering University of UtahSalt Lake City84112USA Institute for Building Materials ETH ZurichZurichSwitzerland Department of Biomedical Engineering University of UtahSalt Lake City84112USA

Age and diabetes have long been known to induce an oxidative reaction between glucose and collagen,leading to the accumulation of advanced glycation end-products(AGEs)cross-links in collagenous *** recently,AGEs content has been related to loss of bone quality,independent of bone mass,and increased fracture risk with aging and *** of bone quality is mostly attributed to changes in material properties,structural organization,or cellular *** all these factors play a role in bone fragility disease,some common recurring patterns can be found between diabetic and age-related bone *** main pattern we will discuss in this viewpoint is the increase of fibrillar collagen stiffness and loss of collagen-induced plasticity with AGE *** study focused on recent related experimental studies and discusses the correlation between fluorescent AGEs content at the molecular and fibrillar scales,collagen deformation mechanisms at the nanoscale,and resistance to bone fracture at the macroscale.

关键词： Bone fragility Advanced glycation end-products Collagen Diabetes Aging

Dairy sheep production research at the University of Wisconsin-Madison,USA-a review

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Journal of Animal Science and Biotechnology 2014年第2期5卷 127-138页

作者： David L Thomas Yves M Berger Brett C McKusick claire M Mikolayunas University of Wisconsin-Madison Department of Animal Sciences Spooner Agricultural research Station Current address:Merial Ltd Midwest Organic Services Association ViroquaWisconsinUSA

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk

关键词： Dairy sheep East Friesian Grazing Lacaune Lactation physiology Nitrogen efficiency rDP rUP Supplementation

Total dysphagia after short course of systemic corticotherapy:Herpes simplex virus esophagitis

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World Journal of Gastroenterology 2013年第31期19卷 5178-5181页

作者： Isa Jetté-Cté Denise Ouellette claire Béliveau Andrew Mitchell Division of Thoracic Surgery Maisonneuve-Rosemont Hospital University of MontrealMontreal H3L 2H8 Canada Department of Infectious Diseases and Microbiology Maisonneuve-Rosemont Hospital University of MontrealMontreal H3L 2H8 Canada Department of Pathology Maisonneuve-Rosemont Hospital University of Montreal Montreal H3L 2H8 Canada

A 72 year-old female developed a herpetic esophagitis after 3 d of oral corticotherapy for an acute exacerbation of chronic obstructive pulmonary disease,presenting as odynophagia and total *** were taken during a first esophagogastroduodenoscopy(EGD) and the patient was referred to the thoracic surgery service with a presumptive diagnosis of esophageal cancer.A second EGD was planned for dilatation,but by that time the stenosis was completely *** biopsies taken during the first EGD revealed multiple herpetic viral inclusions and ulcerations without any dysplasia or *** front of a severe esophageal stenosis,one must still exclude the usual differential diagnosis peptic stenosis and *** of endoscopic lesions can suggest the diagnosis but must be promptly confirmed by biopsy,viral culture or polymerase chain *** immune systemic effects of corticotherapy are well known and herpetic esophagitis occurs most frequently in immunocompromised individuals,this case emphasizes the importance of clinical awareness concerning short courses of corticotherapy for immunocompetent *** article discusses the reactivation process of herpetic infection in this context and addresses its diagnostic and therapeutic issues.

关键词： Herpes simplex Esophagitis Dysphagia Corticosteroids Immunocompetence

Understanding antimicrobial pharmacokinetics in critically ill patients to optimize antimicrobial therapy:A narrative review

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Journal of Intensive Medicine 2024年第3期4卷 287-298页

作者： claire roger Department of Anesthesiology and Intensive Care Pain and Emergency MedicineNîmes-Caremeau University HospitalNîmesFrance Ur UM 103 IMAGINE(Initial Management and prévention of orGan failures IN critically ill patiEnts) Faculty of MedicineMontpellier UniversityMontpellierFrance

Effective treatment of sepsis not only demands prompt administration of appropriate antimicrobials but also requires precise dosing to enhance the likelihood of patient survival. Adequate dosing refers to the administration of doses that yield therapeutic drug concentrations at the infection site. This ensures a favorable clinical and microbiological response while avoiding antibiotic-related toxicity. Therapeutic drug monitoring (TDM) is the recommended approach for attaining these goals. However, TDM is not universally available in all intensive care units (ICUs) and for all antimicrobial agents. In the absence of TDM, healthcare practitioners need to rely on several factors to make informed dosing decisions. These include the patient's clinical condition, causative pathogen, impact of organ dysfunction (requiring extracorporeal therapies), and physicochemical properties of the antimicrobials. In this context, the pharmacokinetics of antimicrobials vary considerably between different critically ill patients and within the same patient over the course of ICU stay. This variability underscores the need for individualized dosing. This review aimed to describe the main pathophysiological changes observed in critically ill patients and their impact on antimicrobial drug dosing decisions. It also aimed to provide essential practical recommendations that may aid clinicians in optimizing antimicrobial therapy among critically ill patients.

关键词： Pharmacokinetics/pharmacodynamics ICU Antibiotics Dose optimization TDM

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A decomposition of light’s spin angular momentum density

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Light(Science & Applications) 2024年第8期13卷 1578-1589页

作者： Alex J.Vernon Sebastian Golat claire rigouzzo Eugene A.Lim Francisco J.rodríguez-Fortuño Department of Physics King’s College LondonStrandLondon WC2R 2LSUK London Centre for Nanotechnology LondonUK

Light carries intrinsic spin angular momentum(SAM)when the electric or magnetic field vector rotates over time.A familiar vector equation calculates the direction of light’s SAM density using the right-hand rule with reference to the electric and magnetic polarisation *** Maxwell’s equations,this vector equation can be decomposed into a sum of two distinct terms,akin to the well-known Poynting vector decomposition into orbital and spin *** present the first general study of this spin decomposition,showing that the two terms,which we call canonical and Poynting spin,are chiral analogies to the canonical and spin momenta of light in its interaction with *** canonical momentum,canonical spin is directly *** canonical and Poynting spin incorporate spatial variation of the electric and magnetic fields and are influenced by optical *** decomposition allows us to show that a linearly polarised vortex beam,which has no total SAM,can nevertheless exert longitudinal chiral pressure due to equal and opposite canonical and Poynting spins.

关键词： canonical momentum angular

Some Implications of the Gessel Identity

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Applied Mathematics 2023年第9期14卷 545-579页

作者： claire Levaillant Department of Mathematics University of Southern California Los Angeles CA USA

We generalize the congruences of Friedmann-Tamarkine (1909), Lehmer (1938), and Ernvall-Metsänkyla (1991) on the sums of powers of integers weighted by powers of the Fermat quotients to the next Fermat quotient power, namely to the third power of the Fermat quotient. Using this result and the Gessel identity (2005) combined with our past work (2021), we are able to relate residues of some truncated convolutions of Bernoulli numbers with some Ernvall-Metsänkyla residues to residues of some full convolutions of the same kind. We also establish some congruences concerning other related weighted sums of powers of integers when these sums are weighted by some analogs of the Teichmüller characters.

关键词： Convolutions Involving Bernoulli Numbers Truncated Convolutions Involving Bernoulli Numbers Congruences Binomial and Multinomial Convolutions of Divided Bernoulli Numbers Multiple Harmonic Sums Generalized Harmonic Numbers Miki Identity Gessel Identity Sums of Powers of Integers Weighted by Powers of the Fermat Quotients Generalization of Kummer’s Congruences Generalizations of Friedmann-Tamarkine Lehmer Ernvall-Metsänkyla’s Congruences p-Adic Numbers Weighted Sums of Powers of Integers