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Intraspecific scaling and early life history determine the cost of free-flight in a large beetle(Batocera rufomaculata)

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Insect Science 2024年第2期31卷 524-532页

作者： Tomer Urcai eran Levin eran Gefen Gal Ribak Faculty of Life Sciences School of ZoologyTel Aviv UniversityTel AvivIsrael Steinhardt Museum of Natural History Israel National Center for Biodiversity StudiesTel AvivIsrael Department of Biology University of Haifa-OranimKiryat TivonIsrael

The scaling of the energetic cost of locomotion with body mass is well documented at the interspecific ***,methodological restrictions limit our understanding of the scaling of flight metabolic rate(MR)in free-flying *** is particularly true at the intraspecific level,where variation in body mass and flight energetics may have direct consequences for the fitness of an *** applied a 13C stable isotope method to investigate the scaling of MR with body mass during free-flight in the beetle Batocera *** species exhibits large intraspecific variation in adult body mass as a consequence of the environmental conditions during larval *** show that the flight-MR scales with body mass to the power of 0.57,with smaller conspecifics possessing up to 2.3 fold higher mass-specific flight MR than larger *** the scaling exponent of free-flight MR was found to be like that determined for tethered-flight,the energy expenditure during free-flight was more than 2.7 fold higher than for *** metabolic cost of flight should therefore be studied under free-flight conditions,a requirement now enabled by the 13C technique described herein for insect flight.

关键词： allometry body mass Coleoptera free-flight insect flight stable carbon isotope tethered-flight

Circumventing the phonon bottleneck by multiphonon-mediated hot exciton cooling at the nanoscale

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npj Computational Materials 2023年第1期9卷 845-852页

作者： Dipti Jasrasaria eran Rabani Department of Chemistry University of CaliforniaBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA The Sackler Center for Computational Molecular and Materials Science Tel Aviv UniversityTel Aviv 69978Israel Present address:Department of Chemistry Columbia UniversityNew YorkNY 10027USA

Nonradiative processes govern efficiencies of semiconductor nanocrystal(NC)-based devices.A central process is hot exciton cooling,or the nonradiative relaxation of a highly excited electron/hole pair to form a band-edge *** to quantum confinement effects,the timescale and mechanism of cooling are not well understood.A mismatch between electronic energy gaps and phonon frequencies has led to the hypothesis of a phonon bottleneck and extremely slow cooling,while enhanced electron-hole interactions have suggested ultrafast *** measurements of the cooling timescale range six orders of ***,we develop an atomistic approach to describe phonon-mediated exciton dynamics and simulate cooling in NCs of experimentally relevant *** find that cooling occurs on~30 fs timescales in CdSe NCs,in agreement with the most recent measurements,and that the phonon bottleneck is circumvented through a cascade of multiphonon-mediated relaxation ***,we identify NC handles for tuning the cooling timescale.

关键词： phonon relaxation excited

Metabolic cost of flight and aerobic efficiency in the rose chafer,Protaetia cuprea(Cetoniinae)

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Insect Science 2022年第5期29卷 1361-1372页

作者： Tomer Urca eran Levin Gal Ribak School of Zoology Faculty of Life SciencesTel Aviv UniversityTel AvivIsrael Steinhardt Museum of Natural History Israel National Center for Biodiversity StudiesTel AvivIsrael

Rose chafer beetles(Protetia cuprea)are pollinators as well as agricultural pests,flying between flowers and trees while foraging for pollen and *** the energy they expend on flying during foraging activity faces the challenge of measuring the metabolic rate(MR)of free-flying insects in an open *** overcame this challenge by using the bolus injection of ^(13)C Na-bicarbonate technique to measure their metabolic energy expenditure while flying in a large flight ***,we tracked the insects with high-speed cameras to extract their flight trajectory,from which we calculated the mechanical power invested in flying for each flight *** found that the chemical(metabolic)energy input converted to mechanical flight energy output at a mean efficiency of 10.4%±5.2%,with a trend of increased efficiency in larger conspecifics(efficiency scaled with body mass to the power of 1.4).The transition in the summer from a diet of pollen to that of fruits may affect the energy budget available for *** ***,feeding on apples ad libitum,increased their body mass by an average of 6%in 2 *** to our calculations,such a meal can power a 630-m flight(assuming a carbohydrate assimilation efficiency of 90%).Pollen,with a low water and carbohydrate content but rich in proteins and lipids,has a higher caloric content and should assimilate differently when converting food to flight *** high cost of aerial locomotion is inherent to the foraging behavior of rose chafers,explaining their short flight bouts followed by prolonged feeding activity.

关键词： aerobic eficieney bolus injection of^(13)C-Na-bicarbonate feeding capacity flight metabolic rate flower chafer bele free flight mechanical power

Multi-dimensional band structure spectroscopy in the synthetic frequency dimension

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Light(Science & Applications) 2023年第7期12卷 1425-1433页

作者： Dali Cheng eran Lustig Kai Wang Shanhui Fan Ginzton Laboratory and Department of Electrical Engineering Stanford UniversityStanfordCA94305USA Department of Physics McGll UniversityMontrealQC H3A 2T8Canada

The concept of synthetic dimensions in photonics provides a versatile platform in exploring multi-dimensional *** of these physics are characterized by band structures in more than one *** efforts on band structure measurements in the photonic synthetic frequency dimension however are limited to either onedimensional Brillouin zones or one-dimensional subsets of multi-dimensional Billouin *** we theoretically propose and experimentally demonstrate a method to fully measure multi-dimensional band structures in the synthetic frequency *** use a single photonic resonator under dynamical modulation to create a multidimensional synthetic frequency *** show that the band structure of such a lattice over the entire multidimensional Brillouin zone can be measured by introducing a gauge potential into the lattice *** this method,we perform experimental measurements of two-dimensional band structures of a Hermitian and a non-Hermitian *** measurements reveal some of the general properties of point-gap topology of the non-Hermitian Hamiltonian in more than one *** results demonstrate experimental capabilities to fully characterize high-dimensional physical phenomena in the photonic synthetic frequency dimension.

关键词： resonator synthetic dimensional

APOE4 expression is associated with impaired autophagy and mitophagy in astrocytes

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Neural Regeneration Research 2022年第4期17卷 777-778页

作者： Schmukler eran Pinkas-Kramarski Ronit Department of Neurobiology School of Neurobiology Biochemistry and BiophysicsTel-Aviv UniversityRamat-AvivIsrael

Among the risk factors for late onset sporadic Alzheimer's disease(AD)is the expression ofε4 allele of apolipoprotein E(APOE4)gene(Mahley et al.,2006).Elevated amyloid processing and reduced degradation of Aβ,which lead to Ap plaque deposition,are evident in APOE4-positive AD patients and mice(Mahley et al.,2006).These features correlate with neuronal cell *** mitochondrial activity and increased oxidative stress have long been recognized as additional hallmarks of AD pathology(Mahley et al.,2006).The effect of APOE4 expression on autophagy and mitochondrial dynamics and activity in astrocytes is discussed in this perspective and is summarized in Figure 1.

关键词： al. impaired Aβ

Risk factors for non-alcoholic fatty liver disease delineate the battlegrounds in optimizing disease prevention

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Hepatobiliary Surgery and Nutrition 2022年第3期11卷 492-494页

作者： Igor Spivak eran Elinav Systems Immunology Department Weizmann Institute of ScienceRehovotIsrael Medical Clinic III University Hospital AachenAachenGermany Division of Cancer-Microbiome Research Deutsches Krebsforschungszentrum(DKFZ)HeidelbergGermany

Multiple environmental factors impact non-alcoholic fatty liver disease(NAFLD).While the association with dietary habits and physical activity is broadly characterized(1),the contribution of socioeconomic disparities to these risk factors remains elusive to date(2).A cross-sectional study of the National Health and Nutrition Examination Surveys(NHANES)(3)recently examined a cohort representative of the adult *** for combined effects of socio-demographic and lifestyle patterns on NAFLD risk *** activity,a high-quality diet and higher education,but not income level,were found to reduce the risk of NALFD,irrespective of ethnicity or *** NAFLD is estimated to affect up to a quarter of the global population and particularly become more prevalent in industrialized countries(4),proper characterization of associated population-based risk factors is crucial in optimizing public health and educatory preventive and treatment directives.

关键词： prevention NAFLD income

Prior abdominal surgery as a potential risk factor for colonic diverticulosis or diverticulitis

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World Journal of Clinical Cases 2023年第35期11卷 8320-8329页

作者： eran Ariam Vered Richter Anton Bermont Yael Sandler Daniel L Cohen Haim Shirin Department of Gastroenterology Kaplan Medical CenterRehovot 76100Israel The Gonczarowski Family Institute of Gastroenterology and Liver Diseases Shamir Medical CenterZerifin 70300Israel and the Faculty of MedicineTel Aviv UniversityTel AvivIsrael Department of Surgery Division Shamir Medical CenterZerifin 70300Israel

BACKGROUND Abnormal colonic pressure profiles have been associated with an increased risk of colonic diverticulosis.A surgical history is a known risk factor for abdominal adhesions and these may lead to increased intraluminal colonic *** To assess whether previous abdominal surgery is associated with colonic divertic-ulosis or *** We analyzed data from a study of patients undergoing colonoscopy for different indications from 2020 through *** completed a structured question-naire concerning previous abdominal surgeries,dietary and lifestyle exposures including smoking,alcohol use and *** Three hundred and fifty-nine patients were included in the *** mean age was 67.6 and 46%were *** mellitus,hypertension,ischemic heart disease,chronic obstructive pulmonary disease,chronic renal failure,and body mass index were similar in the diverticulosis and control *** overall prevalence of colonic diverticulosis was 25%(91/359)and 48%of the patients had previous abdominal *** expected,the prevalence of diverticulosis increased with *** was no difference in the rate of previous abdominal surgery between patients with or without diverticulosis(49%vs 47%,P=0.78).In regards to specific surgeries,inguinal hernia repair was significantly associated with diverticulosis(52%vs 20%,P=0.001),but not *** contrast,appendectomy was not associated with diverticulosis(6%vs 14%,P=0.048).CONCLUSION These findings suggest that post-operative abdominal adhesions inducing high colonic intraluminal pressures do not appear to be the mechanism for diverticula ***,inguinal hernia and diverticulosis may share similar connective tissue pathologies with no causative relationship between them.

关键词： Diverticulosis Diverticulitis General surgery Adhesions Risk factors Abdomen

Neuromuscular junction mitochondrial enrichment: a “double-edged sword” underlying the selective motor neuron vulnerability in amyotrophic lateral sclerosis

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Neural Regeneration Research 2021年第1期16卷 115-116页

作者： Topaz Altman eran Perlson Department of Physiology and Pharmacology Sackler Faculty of MedicineTel-Aviv UniversityTel-AvivIsrael Sagol School of Neuroscience Tel-Aviv UniversityTel-AvivIsrael

Motor neurons are highly polarized cells,with long axons that extend to more than 1 m in the adult *** axons further arborize into a specialized synaptic compartment,the motor unit,containing up to 2000 neuromuscular junctions(NMJs).While the size of other neuronal synapses can be up to 1μm,the NMJ is much larger and can reach 10–30μm(Jones et al.,2017).The vast size of the motor unit requires motor neurons to evolutionally adapt and supply this distal portion with a sufficient amount of ATP,as well as to replenish the axonal protein pool in order to maintain their synapses.

关键词： specialized maintain sword

Global epigenetic changes during somatic cell reprogramming to iPS cells

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分子细胞生物学报:英文版 2011年第6期3卷 341-350页

作者： Anna Mattout Alva Biran eran Meshorer Department of Genetics Institute of Life SciencesThe Hebrew University of JerusalemJerusalem 91904Israel

Embryonic stem cells(ESCs)exhibit unique chromatin features,including a permissive transcriptional program and an open,decondensed chromatin *** pluripotent stem cells(iPSCs),which are very similar to ESCs,hold great promise for therapy and basic ***,the mechanisms by which reprogramming occurs and the chromatin organization that underlies the reprogramming process are largely *** we characterize and compare the epigenetic landscapes of partially and fully reprogrammed iPSCs to mouse embryonic fibroblasts(MEFs)and ESCs,which serves as a standard for *** immuno-fluorescence and biochemical fractionations,we analyzed the levels and distribution of a battery of histone modifications(H3ac,H4ac,H4K5ac,H3K9ac,H3K27ac,H3K4me3,H3K36me2,H3K9me3,H3K27me3,and gH2AX),as well as HP1a and lamin *** find that fully reprogrammed iPSCs are epigenetically identical to ESCs,and that partially reprogrammed iPSCs are closer to ***,combining both time-course reprogramming experiments and data from the partially reprogrammed iPSCs,we find that heterochromatin reorganization precedes Nanog expression and active histone ***,these data delineate the global epigenetic state of iPSCs in conjunction with their pluripotent state,and demonstrate that heterochromatin precedes euchromatin in reorganization during reprogramming.

关键词： chromatin pluripotency reprogramming iPSCs ESCs histone modifications epigenetics