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Excess dietary Lys reduces feed intake, stimulates jejunal CCK secretion and alters essential and non‑essential blood AA profile in pigs

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1336-1346页

作者： Maximiliano Muller Elout van Liefferinge Alan Tilbrook Robert van Barneveld Eugeni Roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandBrisbaneQueensland 4072Australia Laboratory of Animal Nutrition and Animal Product Quality(LANUPRO) Department of Animal Sciences and Aquatic EcologyGhent University339000 GhentFlandersBelgium Centre for Animal Science Queensland Alliance for Agriculture and Food Innovation and the School of Veterinary ScienceThe University of QueenslandBrisbaneQueensland 4072Australia SunPork Group BrisbaneQueensland 4009Australia

Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the herd.However,the provision of dietary excess of AA,such as Lys,may lead to reduced appetite and growth in pigs.The mechanisms modulat-ing these responses have not been extensively investigated.This study evaluated the effect of Lys dietary excesses on performance and satiety biomarkers in post weaning pigs.Methods Twenty-four pigs aged 21 d and weighing 6.81±0.12kg(mean±SEM)were individually housed and offered 1 of 4 dietary treatments for 3weeks:a diet containing a standardized ileal digestible Lys reaching 100%(T0),120%(T1),150%(T2)or 200%(T3)of the NRC(2012)requirements.At the end of the experiment,blood samples from the cephalic vein of the T0 and T3 groups were obtained for AA analysis.In addition,primary intestinal cultures from T0 pigs were used,following their humane killing,to evaluate the effect of Lys on gut hormone secretion and AA sensors gene expression under ex vivo conditions.Results Feed intake was linearly reduced(P<0.001)and the weight gain to feed ratio reduced(P<0.10)with increased dietary levels of Lys during the third-and first-week post weaning,respectively.Cholecystokinin con-centration(P<0.05)and the metabotropic glutamate receptor 1 and the solute carrier family 7 member 2(P<0.10)gene expression was enhanced in proximal jejunum tissues incubated with Lys at 20mmol/L when compared to the control(Lys 0mmol/L).Plasma Lys and Glu(P<0.05)concentration increased in the T3 compared to T0 pigs.In contrast,plasma levels of His,Val,Thr,Leu(P<0.05)and Gln(P<0.10)were lower in T3 than T0 pigs.Conclusion The present results confirm that excess dietary Lys inhibits hunger in pigs.Moreover,the results provide evidence of pre-and post-absorptive mechanisms modulating these responses.Lys dietary excesses should be nar-rowed,when possible,to avoid negative effects of the AA on appetite in pigs.

关键词： Amino acid Blood Cholecystokinin Feed intake Lysine Pig Satiety

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Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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Defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla Roman Vitek Dung Nguyen van Zbynek Krist Hung Nguyen van Department of Weapons and Ammunition University of Defence BrnoCzech Republic Department of Weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the weapon.Earlier works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing rests.For the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were chosen.Calculations show the best accord with experiment when modelling the system with 4 degrees of freedom.The oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock absorbers.The velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

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Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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National Science Review 2024年第3期11卷 183-191页

作者： Yibo Wang van A.Ngo Xiaohui Wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of Applied Chemistry and Engineering University of Science and Technology of China Beijing National Laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of MOR.Furthermore, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

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Sturge–Weber syndrome:an update for the pediatrician

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World Journal of Pediatrics 2024年第5期20卷 435-443页

作者： Emilie Dingenen Damien Segers Hannelore De Maeseneer Dirk van Gysel Ghent University Faculty of Medicine and Health Sciences GhentBelgium Department of Pediatrics O.L.Vrouw Hospital AalstMoorselbaan 1649300AalstBelgium Interdisciplinary Unit of Pediatric Dermatology Vrije Universiteit Brussel(VUB)Universitair Ziekenhuis Brussel(UZ Brussel)BrusselsBelgium

Sturge–Weber syndrome(SWS)is a rare congenital neurocutaneous disorder characterized by the simultaneous presence of both cutaneous and extracutaneous capillary malformations.SWS usually presents as a facial port-wine birthmark,with a varying presence of leptomeningeal capillary malformations and ocular vascular abnormalities.The latter may lead to significant neurological and ocular morbidity such as epilepsy and glaucoma.SWS is most often caused by a somatic mutation involving the G protein subunit alpha Q or G protein subunit alpha 11 gene causing various alterations in downstream signaling pathways.We specifically conducted a comprehensive review focusing on the current knowledge of clinical practices,the latest pathophysiological insights,and the potential novel therapeutic avenues they provide.Data sources A narrative,non-systematic review of the literature was conducted,combining expert opinion with a balanced review of the available literature.A search of PubMed,Google Scholar and Embase was conducted,using keywords“Sturge–Weber Syndrome”OR“SWS”,“Capillary malformations”,“G protein subunit alpha 11”OR“G protein subunit alpha Q”.Results One of the hallmark features of SWS is the presence of a port-wine birthmark at birth,and forehead involvement is most indicative for SWS.The most common ocular manifestations of SWS are glaucoma and choroidal hemangioma.Glaucoma presents in either in infancy(0–3 years of age)or later in life.Neurological complications are common in SWS,occurring in about 70%–80%of patients,with seizures being the most common one.SWS significantly impacts the quality of life for patients and their families,and requires a multidisciplinary approach for diagnosis and treatment.Currently,no disease-modifying therapies exist,and treatment is mostly focused on symptoms or complications as they arise.Conclusions SWS remains a complex and heterogeneous disorder.Further research is needed to optimize diagnostic and therapeutic strategies,and to translate insights from molecular pathogenesis to clin

关键词： Capillary malformations G-protein Gq-G11 Port-wine birthmark Neurocutaneous disorder Sturge-Weber syndrome

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Nonsteroidal anti-inflammatory drugs before endoscopic ultrasound guided tissue acquisition to reduce the incidence of post procedural pancreatitis

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World Journal of Gastroenterology 2024年第8期30卷 811-816页

作者： Mike de Jong Foke van Delft Christine Roozen Erwin-Jan van Geenen Tanya Bisseling Peter Siersema Marco Bruno Department of Gastroenterology and Hepatology Radboud University Medical CenterNijmegen 6525 GANetherlands Department of Gastroenterology and Hepatology Erasmus University Medical CenterRotterdam 3015 GDNetherlands

Endoscopic ultrasound(EUS)with fine needle aspiration or fine needle biopsy is the gold standard for sampling tissue to diagnose pancreatic cancer and auto-immune pancreatitis or to analyze cyst fluid.The most common reported adverse event of fine needle aspiration and/or fine needle biopsy is acute pancreatitis,which is likely induced by the same pathophysiological mechanisms as after en-doscopic retrograde cholangiopancreatography(ERCP).According to the current European Society of Gastrointestinal Endoscopy guideline,nonsteroidal anti-inflammatory drugs are administered prior to ERCP as a scientifically proven treatment to reduce post-ERCP pancreatitis incidence rate.A single suppository of diclofenac or indomethacin prior to EUS guided tissue acquisition(TA)is harm-less in healthy adults.Since it is associated with low costs and,most important,may prevent a dreadsome complication,we strongly recommend the adminis-tration of 100 mg diclofenac rectally prior to EUS-TA.We will explain this recom-mendation in more detail in this review as well as the risk and pathophysiology of post-EUS TA pancreatitis.

关键词： Pancreatitis Endoscopic ultrasound Tissue acquisition Nonsteroidal antiinflammatory drugs Pancreatic cancer

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No evidence of predator odor avoidance in a North American bird community

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Avian Research 2024年第1期15卷 133-138页

作者： Austin Dotta Batur Yaman Alex van Huynh Department of Biology DeSales University2755 Station AvenueCenter ValleyPAUSA

Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and contexts.Here we assess if a community of birds in eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging setting.We use clay caterpillars to measure foraging activity by birds in the presence of predator(bobcat)urine,non-predator(rabbit)urine,and water controls in two different environmental contexts(field vs.forest).Although we detected a weak trend for birds to forage less at predator urine-treated sites,we found no significant difference in avian foraging between the site types.We did find that foraging rates between environmental contexts changed significantly over the course of the experiment,with forest sites showing decreasing foraging rates and field sites showing increasing foraging rates.Our results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species.

关键词： Foraging Odor Olfaction Predation Predator-avoidance

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Transient responses of double-curved sandwich two-layer shells resting on Kerr's foundations with laminated three-phase polymer/GNP/fiber surface and auxetic honeycomb core subjected to the blast load

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Defence Technology（防务技术） 2024年第5期35卷 222-247页

作者： Nguyen Thi Hai van Thi Hong Nguyen Researcher&Lecturer Faculty of Industrial EducationThe University of Danang-University of Technology and Education48 Cao ThangDanang550000Viet Nam Researcher&Lecturer Faculty of Mechanical EngineeringThuyloi University175 Tay SonDong DaHanoi100000Viet Nam

This work uses refined first-order shear theory to analyze the free vibration and transient responses of double-curved sandwich two-layer shells made of auxetic honeycomb core and laminated three-phase polymer/GNP/fiber surface subjected to the blast load.Each of the two layers that make up the double-curved shell structure is made up of an auxetic honeycomb core and two laminated sheets of three-phase polymer/GNP/fiber.The exterior is supported by a Kerr elastic foundation with three characteristics.The key innovation of the proposed theory is that the transverse shear stresses are zero at two free surfaces of each layer.In contrast to previous first-order shear deformation theories,no shear correction factor is required.Navier's exact solution was used to treat the double-curved shell problem with a single title boundary,while the finite element technique and an eight-node quadrilateral were used to address the other boundary requirements.To ensure the accuracy of these results,a thorough comparison technique is employed in conjunction with credible statements.The problem model's edge cases allow for this kind of analysis.The study's findings may be used in the post-construction evaluation of military and civil works structures for their ability to sustain explosive loads.In addition,this is also an important basis for the calculation and design of shell structures made of smart materials when subjected to shock waves or explosive loads.

关键词： Blast load Two-layer shell Polymer/GNP/Fiber surface Auxetic honeycomb Shear connectors

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Perspectives for delivery of therapeutics by extravasation of biodegradable microspheres in the brain

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Neural Regeneration Research 2024年第5期19卷 969-970页

作者： Anne-Eva van der Wijk Ed vanBavel Amsterdam UMC location University of Amsterdam Department of Biomedical Engineering and PhysicsAmsterdamThe Netherlands Amsterdam Neuroscience Neurovascular Disorders ProgramAmsterdamThe Netherlands Amsterdam Cardiovascular Sciences Microcirculation ProgramAmsterdamThe Netherlands

Development of therapeutics for brain diseases has remained challenging,in particular due to the difficulty of passing the blood-brain barrier.As a result,the current arsenal of therapeutics targeting the brain is limited to small,lipid-soluble drugs and there is a lack of options for treating neuroblastomas,Alzheimer’s disease,and many other devastating pathologies.Despite the advances in strategies for crossing the blood-brain barrier such as the use of nanoparticles(Hersh et al.,2022;Duan et al.,2023),such delivery systems have not yet reached clinical practice.Therefore,novel platforms for the transport of therapeutics across the blood-brain barrier remain highly desired.This specifically holds for large molecules such as monoclonal antibodies and recombinant proteins,as well as nucleotide-based therapeutics and cell therapies.Research efforts in this field are increasing exponentially,with thousands of publications in the last few years.

关键词： therapeutics holds spite

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An isogeometric approach to static and transient analysis of fluid-infiltrated porous metal foam piezoelectric nanoplates with flexoelectric effects and variable nonlocal parameters

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 461-489页

作者： Quoc-Hoa PHAM van Ke Tran Phu-Cuong Nguyen Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam

In this work,a novel refined higher-order shear deformation plate theory is integrated with nonlocal elasticity theory for analyzing the free vibration,bending,and transient behaviors of fluid-infiltrated porous metal foam piezoelectric nanoplates resting on Pasternak elastic foundation with flexoelectric effects.Isogeometric analysis(IGA)and the Navier solution are applied to the problem.The innovation in the present study is that the influence of the in-plane variation of the nonlocal parameter on the free and forced vibration of the piezoelectric nanoplates is investigated for the first time.The nonlocal parameter and material characteristics are assumed to be material-dependent and vary gradually over the thickness of structures.Based on Hamilton’s principle,equations of motion are built,then the IGA approach combined with the Navier solution is used to analyze the static and dynamic response of the nanoplate.Lastly,we investigate the effects of the porosity coefficients,flexoelectric parameters,elastic stiffness,thickness,and variation of the nonlocal parameters on the mechanical behaviors of the rectangular and elliptical piezoelectric nanoplates.

关键词： isogeometric analysis fluid-infiltrated porous piezoelectric nanoplates static and transient analysis flexoelectric effect variable nonlocal parameters

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Adhesion performance of alkali-activated material for 3-dimensional printing of tunnel linings at different temperatures

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 66-79页

作者： Yaxin TAO Xiaodi DAI Geert de SCHUTTER Kim van TITTELBOOM Department of Structural Engineering and Building Materials Ghent UniversityGhent 9052Belgium

Robotic-based technologies such as automated spraying or extrusion-based 3-dimensional(3D)concrete printing can be used to build tunnel linings,aiming at reducing labor and mitigating the associated safety issues,especially in the high-geothermal environment.Extrusion-based 3D concrete printing(3DCP)has additional advantages over automated sprayings,such as improved surface quality and no rebound.However,the effect of different temperatures on the adhesion performance of 3D-printed materials for tunnel linings has not been investigated.This study developed several alkali-activated slag mixtures with different activator modulus ratios to avoid the excessive use of Portland cement and enhance sustainability of 3D printable materials.The thermal responses of the mixtures at different temperatures of 20 and 40℃ were studied.The adhesion strength of the alkali-activated material was evaluated for both early and later ages.Furthermore,the structural evolution of the material exposed to different temperatures was measured.This was followed by microstructure characterization.Results indicate that elevated temperatures accelerate material reactions,resulting in improved early-age adhesion performance.Moreover,higher temperatures contribute to the development of a denser microstructure and enhanced mechanical strength in the hardened stage,particularly in mixtures with higher silicate content.

关键词： alkali-activated material 3DCP tunnel lining high-geothermal environment adhesion

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