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Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin T.moran michael R.Bedford Poultry Science Department Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca2+near the enzyme?s active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca2+, destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca2+and other cations rebind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes(e.g. Ca2+, Zn2+) which reduces their structural resistance to autolysis and ability as co-factors(e.g. Zn2+) to increase enzyme activity. Goblet cells initially employ Ca2+as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca2+is progressively displaced by Na+to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer（USWL）. Excessive removal of Ca2+from mucin by phytic acid increases its fluidity facilitating its loss from the USWL with

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

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Overshoot phenomena:Observation and simulation

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Earth and Planetary Physics 2024年第2期8卷 391-399页

作者： Ting Feng moran Liu ShiMin He Xiang Wang Chen Zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

High-power O-mode radio waves can excite artificial instabilities in the F region,according to experiments conducted at the European Incoherent Scatter Science Association(EISCAT)heating *** main instabilities include the parametric decay instability(PDI),oscillating two-stream instability(OTSI),and thermal parametric instability(TPI).The PDI and OTSI not only compete with each other,but also compete with the TPI,leading to a two-stage overshoot phenomenon:a miniovershoot occurs on a millisecond time scale after pump-on,followed by the main *** gain insight into the miniovershoot via a generalized Zakharov model,whereas the main overshoot can be observed as an enhanced plasma line overshoot phenomenon in incoherent scatter radar *** can also observe that the zero-frequency ion line exists only in the initial heating period after a cold start and that the upshifted and downshifted ion lines behave irregularly in the *** simulation results show that competition between the PDI and OTSI leads to an initial peak,which we named the *** following processes,namely ion density caviton generation,and collapse and cascade in the development of the PDI,contribute to the miniovershoot phenomenon.

关键词： overshoot parametric decay instability oscillating two-stream instability competition

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Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: Detailed structural investigation

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Nano Research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion *** separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent *** patterns produced had long-range order and domain sizes>1μ*** BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP *** ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room *** oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide *** mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate *** formation and stability of the sulphide nanowires were studied at different *** photoluminescence and Raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence

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A GHz chirped amplitude-modulated laser for high-contrast plasma gratings

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High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： michael Valdman Amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

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Neuronal trafficking as a key to functional recovery in immune-mediated neuropathies

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Neural Regeneration Research 2024年第11期19卷 2331-2332页

作者： Felix Kohle michael Schroeter Department of Neurology University of Cologne and University Hospital CologneCologneGermany

Immune-mediated neuropathies are rare diseases of the peripheral nervous system(PNS),substantially affecting patients’functionality and quality of *** are amenable to immunomodulatory treatments,which in many cases stabilize disease progression,but long-term deficits persist in many *** long-term deficits are particularly observed in monophasic autoimmune neuropathies like Guillain-Barrésyndrome and also in chronic variants,e.g.,chronic inflammatory demyelinating neuropathy(Fadia et al.,2019).

关键词： diseases autoimmune

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Transcranial photobiomodulation for the brain: a wide range of clinical applications

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Neural Regeneration Research 2024年第3期19卷 483-484页

作者： michael R.Hamblin Laser Research Centre Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation therapy(PBMT)is a rapidly growing approach to the healing,stimulation,protection,and regeneration of many human organs and tissue *** started in the 1960s as low-level laser therapy for wound healing,but since then the introduction of light-emitting diodes(LEDs)has dramatically increased the number of applications and reports of positive *** generally uses red(620-700 nm)and/or near-infrared(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular mechanisms(de Freitas and Hamblin,2016).While laser therapists continue to use various types of laser in their office practice,LEDs are ideally suited for home use devices because they are completely safe and without any known significant adverse *** the various body parts on which PBMT has been shown to exert beneficial effects,the brain stands out as perhaps the most promising *** has been shown to reduce neuroinflammation,while increasing mitochondrial function,oxygen consumption,and blood flow within the brain(Hamblin,2016).Moreover,PBMT can stimulate the processes of synaptogenesis,neurogenesis,and neuroplasticity thus helping the brain to heal itself.

关键词： healing stimulation wound

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Influence of overhanging tool length and vibrator material on electromechanical impedance and amplitude prediction in ultrasonic spindle vibrator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 292-310页

作者： Rendi KURNIAWAN moran XU Min Ki CHOO Shuo CHEN Yein KWAK' Jielin CHEN Saood ALI Hanwei TENG Pil Wan HAN Gi Soo KIM Tae Jo KO Precision Machining Laboratory Department of Mechanical Engineering Yeungnam UniversityGyeongsansiGyeongbuk-doRepublic of Korea Korea Electrotechnology Research Institute(KERI) ChangwonsiGyeongsangnam-doRepublic of Korea KASWIN Co. LtdChangwon-siGyeongsangnamdoRepublic of Korea

This study presents the development of an ultrasonic transducer with a radius horn for an ultrasonic milling spindle(UMS)*** ultrasonic transducer was intended to have a working frequency of approximately 30 *** different materials were considered in the study:stainless steel(SS 316L)and titanium alloy(Ti-6Al-4V).Titanium alloy gave a higher resonance frequency(33 kHz)than stainless steel(30 kHz)under the same preload compression *** electromechanical impedance simulation was carried out to predict the impedance resonance frequency for both materials,and the effect of the overhanging toolbar was *** to the electromechanical impedance simulation,the overhanging toolbar length affected the resonance frequency,and the error was less than 3%.Harmonic analysis confirmed that the damping ratio helps determine the resonance ***,damping ratios of 0.015-0.020 and 0.005-0.020 were selected for stainless steel and titanium alloy,respectively,with an error of less than 1.5%.Experimental machining was also performed to assess the feasibility of ultrasonic-assisted milling;the result was a lesser cutting force and better surface topography of Al 6061.

关键词： Ultrasonic spindle Ultrasonic vibration assisted-milling(UVAM) 1-degree of freedom(DOF) Frequency Amplitude Milling

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A Tropical View on Landau-Ginzburg Models

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Acta Mathematica Sinica,English Series 2024年第1期40卷 329-382页

作者： michael CARL Max PUMPERLA Bernd SIEBERT Alfred-Delp-Str.2 73430 AalenGermany IU Internationale Hochschule Juri-Gagarin-Ring 15299084 ErfurtGermany AnyscaleInc.2080 Addison St Ste 7BerkeleyCA 94704USA Department of Mathematics The Univ.of Texas at Austin2515 SpeedwayAustinTX 78712USA

This paper,largely written in 2009/2010,fits Landau-Ginzburg models into the mirror symmetry program pursued by the last author jointly with Mark Gross since *** point of view transparently brings in tropical disks of Maslov index 2 via the notion of broken lines,previously introduced in two dimensions by Mark Gross in his study of mirror symmetry for P2.A ma jor insight is the equivalence of properness of the Landau-Ginzburg potential with smoothness of the anticanonical divisor on the mirror *** obtain proper superpotentials which agree on an open part with those classically known for toric *** include mirror LG models for non-singular and singular del Pezzo surfaces,Hirzebruch surfaces and some Fano threefolds.

关键词： Landau-Ginzburg model mirror symmetry tropical disk broken line wall structure scattering diagram Gross-Siebert program del Pezzo surface toric degeneration

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Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles michael Albert Kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

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Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

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Particuology 2024年第6期89卷 198-210页

作者： michael Mascara Arno Mayrhofer Stefan Radl Christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing GmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus G′and loss modulus G″,are *** is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale *** Burgers model,vastly used in literature to model viscoelastic systems,is discretized and *** test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear *** appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the ***,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers *** micro-contact parameters are obtained from the macro parameters through appropriate *** completing a frequency sweep,the simulated G′and G″show a relatively large error,around 25%for G’for *** this reason,a more robust model,namely the generalized Maxwell model,has been *** calibration procedure is performed in the same fashion as for the Burgers ***,the tangential micro-contact parameters are scaled *** normal *** scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both G′and G″for a large ***,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEM Rheology Numerical modeling Viscoelasticity

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