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synthetic polymers:A review of applications in drilling fluids

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Petroleum science 2024年第1期21卷 475-518页

作者： shadfar Davoodi mohammed Al-shargabi david A.Wood Valeriy s.Rukavishnikov Konstantin m.minaev school of Earth sciences&Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia DWA Energy Limited LincolnUnited Kingdom

With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various ***,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(sPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling ***,compared to modified natural polymers,sPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization *** provide substantial flexibility in their ***,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling *** can be classified based on chemical ingredients,type of reaction,and their responses to ***,some of sPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent sP use in some medium and deep ***,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of sPs in drilling *** contributions of sPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in *** mechanisms,impacts,and advances achieved when sPs are added to drilling fluids are also *** typical challenges encountered by sPs when deployed in drilling fluids and their advantages and drawbacks are also *** issues also impact the applications of sPs in drilling ***,the cost of the most relevant sPs,and the monomers used in their synthesis,are *** impacts of sPs when deployed in drilling fluids,and t

关键词： synthetic versus natural polymers Nanopolymers Drilling fluid additives Lubricity Clay swelling Hole cleaning

Role of climatic variability in shaping intraspecific variation of thermal tolerance in mediterranean water beetles

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Insect science 2024年第1期31卷 285-298页

作者： susana Pallarés david Garoffolo Belén Rodríguez david sánchez-Fernández Department of Zoology University of SevilleSevilleSpain Faculty of Biology Department of Ecology and HydrologyUniversity of MurciaCampus EspinardoMurciaSpain

The climatic variability hypothesis(CVH)predicts that organisms in more thermally variable environments have wider thermal breadths and higher thermal plasticity than those from more stable ***,due to evolutionary trade-offs,taxa with greater absolute thermal limits may have little plasticity of such limits(trade-off hypothesis).The CVH assumes that climatic variability is the ultimate driver of thermal tolerance variation across latitudinal and altitudinal gradients,but average temperature also varies along such *** explored intraspecific variation of thermal tolerance in three typical mediterranean saline water beetles(families Hydrophilidae and Dytiscidae).For each species,we compared two populations where the species coexist,with similar annual mean temperature but contrasting thermal variability(continental *** population).We estimated thermal limits of adults from each population,previously acclimated at 17,20,or 25℃.We found species-specific patterns but overall,our results agree with the CVH regarding thermal ranges,which were wider in the continental(more variable)*** the two hydrophilid species,this came at the cost of losing plasticity of the upper thermal limit in this population,supporting the trade-off hypothesis,but not in the dytiscid *** results support the role of local adaptation to thermal variability and trade-offs between basal tolerance and physiological plasticity in shaping thermal tolerance in aquatic ectotherms,but also suggest that intraspecific variation of thermal tolerance does not fit a general pattern among aquatic *** such intraspecific variation could lead to inaccurate predictions of the vulnerability of aquatic insects to global warming.

关键词： acclimation capacity aquatic insects climate change heat coma temperature supercooling point thermal plasticity

The role of N-glycosylation in cancer

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Acta Pharmaceutica sinica B 2024年第3期14卷 1098-1110页

作者： Yu Lin david m.Lubman Department of surgery University of Michigan Medical CenterAnn ArborMI 48109USA

Despite advances in understanding the development and progression of cancer in recent years,there remains a lack of comprehensive characterization of the cancer *** play an important role in medicine and are involved in various human disease conditions including ***-moieties participate in fundamental cancer processes like cell signaling,invasion,angiogenesis,and *** N-glycosylation significantly impacts cancer processes and targeted therapies in ***,understanding N-glycosylation in a tumor is essential for comprehending disease progression and discovering anti-cancer targets and biomarkers for therapy monitoring and *** review presents the fundamental process of protein N-glycosylation and summarizes glycosylation changes in tumor cells,including increased terminal sialylation,N-glycan branching,and ***,the role of N-glycosylation in tumor signaling pathways,migration,and metabolism are *** and glycopeptides as potential biomarkers for early detection of cancer based on site specificity have been ***,understanding and exploring the cancer glycoproteome,along with its role in medicine,implication in cancer and other human diseases,highlights the significance of N-glycosylation in tumor processes,necessitating further research for potential anticancer targets and biomarkers.

关键词： N-Glycosylated proteins Cancer signaling Cancer angiogenesis Cancer metabolism Cancer biomarkers

Evaluation of hand infections in the emergency department using point-of-care ultrasound

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World Journal of Emergency medicine 2024年第4期15卷 283-288页

作者： david Ahmad Haidar david mintz Brandon m Wubben Omar Rizvi srikar Adhikari Department of Emergency medicine Michigan MedicineAnn Arbor 48109-1382USA University of Arizona College of medicine Tucson 85724USA Department of Emergency medicine University of IowaIowa City 52242-1009USA Department of surgery University of Arizona College of MedicineTucson 85724USA Department of Emergency medicine University of Arizona College of MedicineTucson 85724USA

BACKGROUND:We aimed to evaluate the utility of point-of-care ultrasound(POCUs)in the assessment of hand infections that present to the emergency department(ED)and its impact on medical decision making and patient ***:We conducted a retrospective review of patients who presented to two urban academic EDs with clinical presentations concerning for skin and soft tissue infections(ssTI)of the hand between December 2015 and December *** trained POCUs fellowship physicians reviewed an ED POCUs database for POCUs examinations of the *** then reviewed patients’electronic health records(EHR)for demographic characteristics,history,physical examination findings,ED course,additional imaging studies,consultations,impact of POCUs on patient care and final ***:We included a total of 50 cases(28 male,22 female)in the final *** most common presenting symptoms and exam findings were pain(100%),swelling(90%),and erythema(74%).The most common sonographic findings were edema(76%),soft tissue swelling(78%),and fluid surrounding the tendon(57%).POCUs was used in medical decision making 68%of the time(n=34),with the use of POCUs leading to changes in management 38%of the time(n=19).POCUs use led to early antibiotic use(11/19),early consultation(10/19),and led to the performance of a required procedure(8/19).The POCUs diagnosis was consistent with the discharge diagnosis of flexor tenosynovitis 8/12 times,abscess 12/16 times,and cellulitis 14/20 ***:POCUs is beneficial for evaluating of hand infections that present to the ED and can be used as an important part of medical decision making to expedite patient care.

关键词： Ultrasound Point-of-care ultrasound Cellulitis Abscess Flexor tenosynovitis

Assessing the energy saving potential of using adaptive setpoint temperatures:The case study of a regional adaptive comfort model for Brazil in both the present and the future

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Building simulation 2024年第3期17卷 459-482页

作者： Daniel sánchez-García david Bienvenido-Huertas Carlos Rubio-Bellido Ricardo Forgiarini Rupp Department of Electrical Engineering University Carlos III of MadridMadridSpain Department of Building simulation ZEROCEM SLSevilleSpain Department of Building Constructions University of GranadaGranadaSpain Department of Building Constructions II University of SevilleSevilleSpain section of Design for sustainability Department of Civil and Mechanical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy *** studies using adaptive setpoint temperatures incorporate international models from AsHRAE standard 55 and *** study,however,has instead considered a regional Brazilian adaptive comfort *** study investigates the energy demand arising from the use of a local Brazilian comfort model in order to assess the energy implications from the use of the worldwide AsHRAE standard 55 adaptive model and various fixed setpoint *** of Brazil’s climate zones,full air-conditioning,mixed-mode building operating modes,present-day climate change scenarios,and future scenarios—specifically Representative Concentration Pathways(RCP)2.6,4.5,and 8.5 for the years 2050 and 2100—have all been taken into account in building energy *** use of adaptive setpoint temperatures based on the Brazilian local model considering mixed-mode has been found to significantly reduce energy consumption when compared to static setpoint temperatures(average energy-saving values ranging from 52%to 58%)and the AsHRAE 55 adaptive model(average values ranging from 15%to 21%).Considering climate change and the mixed-mode Brazilian model,the overall energy demand for the three groups of climatic zones(annual average outdoor temperatures≤21℃,>21 and≤25℃and>25℃)ranged between 2%decrease and 5%increase,4%and 27%increase,and 13%and 45%increase,*** is concluded as a consequence that setting setpoint temperatures based on the Brazilian local adaptive comfort model is a very efficient energy-saving method.

关键词： adaptive thermal comfort building energy simulation energy efficiency climate change adaptive setpoint temperatures local comfort mode

mitochondrial recruitment in myelin:an anchor for myelin dynamics and plasticity?

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Neural Regeneration Research 2024年第7期19卷 1401-1402页

作者： Jean-david m.Gothié Timothy E.Kennedy Department of Neurology and Neurosurgery Montreal Neurological InstituteMcGill UniversityMontrealQCCanada

Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by *** is an extension of the oligodendrocyte plasma membrane,which wraps around an axon to form a compact multi-layered *** is composed of a substantially higher proportion of lipids compared to other biological membranes and enriched in a small number of specialized proteins.

关键词： plasticity insulation dynamics

Loss to specialized Cardiology Follow-Up in Adults Living with Congenital Heart Disease

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Congenital Heart Disease 2024年第1期19卷 49-63页

作者： Cheryl Dickson Danielle Osborn david Baker Judith Fethney david s.Celermajer Rachael Cordina Department of Cardiology Royal Prince Alfred HospitalSydneyAustralia Department of Cardiothoracic surgery Westmead HospitalSydneyAustralia susan Wakil school of Nursing and midwifery The University of SydneySydneyAustralia sydney medical school The University of SydneySydneyAustralia

Background:much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care *** less is understood about the loss to follow-up(LTF)after a successful *** is critical too,as patients lost to specialised care are more likely to experience mor-bidity and premature ***:To understand the prevalence and reasons for loss to follow-up(LTF)at a large Australian Adult Congenital Heart Disease(ACHD)***:Patients with moderate or highly complex CHD and gaps in care of>3 years(deﬁned as LTF)were identiﬁed from a comprehensive ACHD *** telephone interviews examined current care and barriers to clinic ***:Overall,407(22%)of ACHD patients(n=1842)were *** mean age at LTF was 31(sD 11.5)years and 54%were male;311(76%)were *** to adults seen regularly,lost patients were younger,with a greater socio-economic disadvantage,and had less complex CHD(ps(14%).The top 3 responses for care absences were“feeling well”(61%),losing track of time(36%),and not needing fol-low-up care(25%).Conclusions:A large proportion of the ACHD population becomes lost to specialised cardiac care,even after a successful *** Australian study reports younger age,moderate complexity defects,and socio-economic disadvantage as predictive of loss to *** study highlights the need for novel approaches to patient-centered service delivery even beyond the age of transition and resources to maintain patient engagement within the ACHD service.

关键词： Loss to follow-up follow-up adult congenital heart disease lapse in care gaps in care care gaps care continuity ACHD predictors

Bed inventory balance and stability of dual circulating fluidized bed systems

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Particuology 2024年第1期84卷 98-106页

作者： Yangjun Wei Leming Cheng david Pallares Bo Leckner Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou310027China Department of space Earth and EnvironmentChalmers University of TechnologyS-41296GöteborgSweden

Experiments and modelling are conducted for general understanding on the imbalance phenomenon and for discussion on the strategies to improve the bed inventory balance and stability of a dual circulating fluidized bed(DCFB)*** experiments are carried out in a 15.5 m high pilot-scale DCFB cold test system.A fluid-dynamic DCFB model is developed based on a 1.5-dimensional semi-empirical model of an industrial CFB boiler,validated by experimental *** effects of control methods and operation conditions on the bed inventory balance and on the stability of the pilot-and large-scale DCFB systems are discussed.A"stable-unbalanced"state,where the system reaches a steady state,consisting of un-balanced bed inventories,is observed in both experiments and model *** maintain a balanced state and similar bed inventory in the DCFB systems with similar cross-sectional areas,it is recom-mended to keep similar total pressure drops or gas velocities in both reactors.

关键词： Bed inventory balance stability Dual circulating fluidized bed(DCFB) Experiment modelling

single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： samuel s.Hardisty Xiaoqian Lin Anthony R.J.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(sWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the sWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts