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Potential Autonomous Selfing in Gesneria citrina (Gesneriaceae),a Specialized Hummingb.rd Pollinated Species with Variab.e Expression of Herkogamy

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Journal of Integrative Plant b.ology 2009年第10期51卷 973-978页

作者： Xin-Sheng Chen Silvana Marten-Rodriguez Qing-Jun Li charles b. fenster Xishuangb.nna Tropical b.tanical Garden the Chinese Academy of Sciences Mengla 666303 China Department of b.ology University of Maryland College Park MD 20742 USA Herb.rio de la Universidad de Costa Rica Escuela de Biologia Ciudad Universitaria Rodrigo Facio San Pedro San Jose Costa Rica

Species with mixed mating systems often demonstrate variab.e expression of b.eeding system characteristics and thus represent the opportunity to understand the factors and mechanisms that promote b.th outcrossed and selfed seed production. Here, we investigate variation in levels of herkogamy （variation in stigma-anther separation distance） in a Puerto Rican population of hummingb.rd pollinated Gesneria citrina Urb.n. There is significant variation in herkogamy levels among individuals of this species and stigma-anther separation is negatively associated with the ab.lity to set fruits and seeds in the ab.ence of pollinators. The variation in levels of herkogamy may represent a mechanism to ensure the production of some self-fertilized progeny in the ab.ence of hummingb.rd pollinators. We also describ. a novel b.eeding system in G. citrina, where stamens elongate over time to reach stigma height, b.t stamen elongation is accelerated b. pollination. These results suggest that once the flowers are pollinated, stamen elongation may favor increased pollen removal and siring success, while the reduction in stigma-anther distance no longer imposes the risk of interference b.tween male and female functions. We discuss our findings of b.eeding system variation in the context of pollination system evolution in an island setting （Antillean islands）.

关键词： mixed-mating pollen limitation pollination system Puerto Rico reproductive assurance stigma-anther separation.

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Function and dysfunction of GEMIN5:understanding a novel neurodevelopmental disorder

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Neural Regeneration Research 2024年第11期19卷 2377-2386页

作者： charles H.Nelson Udai b.Pandey Department of Pediatrics Division of Child NeurologyChildren’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA Children’s Neuroscience Institute Children’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA

The recent identification of a neurodevelopmental disorder with cereb.llar atrophy and motor dysfunction(NEDCAM)has resulted in an increased interest in GEMIN5,a multifunction RNA-b.nding *** the largest memb.r of the survival motor neuron complex,GEMIN5 plays a key role in the b.ogenesis of small nuclear rib.nucleoproteins while also exhib.ting translational regulatory functions as an independent *** many questions remain regarding b.th the pathogenesis and pathophysiology of this new disorder,considerab.e progress has b.en made in the b.ief time since its *** this review,we examine GEMIN5 within the context of NEDCAM,focusing on the structure,function,and expression of the protein specifically in regard to the disorder ***,we explore the current animal models of NEDCAM,as well as potential molecular pathways for treatment and future directions of *** review provides a comprehensive overview of recent advances in our understanding of this unique memb.r of the survival motor neuron complex.

关键词： cereb.llar atrophy GEMIN5 neurodevelopmental disorder neurological disease SMN complex

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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon b.real forest

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Integrative Zoology 2024年第1期19卷 27-36页

作者： charles J.KREb. Alice J.KENNEY b.Scott GILb.RT Rudy b.ONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewab.e Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of b.ological Sciences University of Toronto ScarboroughTorontoOntarioCanada

b.seline studies of small rodent populations in undisturb.d ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American b.real forest,the red-b.cked vole Clethrionomys *** voles b.eed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change b.ing that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numb.rs,and winter weather,and for 1-year social interactions,to estimate their contrib.tion to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contrib.te to changes in density,and we measured their relative contrib.tions statistically with multiple *** rate of winter decline in density was related to b.th food supply and winter *** rate of summer increase was related to summer b.rry crops and white spruce cone *** measure of predator numb.rs was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may b. an understanding of social interactions at high density.

关键词： b.real forest climate change density dependence population cycles predation winter severity

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Synchronization and firing mode transition of two neurons in a b.lateral auditory system driven b. a high–low frequency signal

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Chinese Physics b 2024年第5期33卷 722-735页

作者： charles Omotomide Apata 唐浥瑞周祎凡蒋龙裴启明 School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhou 434023China

The FitzHugh–Nagumo neuron circuit integrates a piezoelectric ceramic to form a piezoelectric sensing neuron,which can capture external sound signals and simulate the auditory neuron *** piezoelectric sensing neurons are coupled b. a parallel circuit consisting of a Josephson junction and a linear resistor,and a b.naural auditory system is *** the non-singleness of external sound sources,the high–low frequency signal is used as the input signal to study the firing mode transition and synchronization of this *** is found that the angular frequency of the high–low frequency signal is a key factor in determining whether the dynamic b.haviors of two coupled neurons are *** they are in synchronization at a specific angular frequency,the changes in physical parameters of the input signal and the coupling strength b.tween them will not destroy their *** addition,the firing mode of two coupled auditory neurons in synchronization is affected b. the characteristic parameters of the high–low frequency signal rather than the coupling *** asynchronous dynamic b.havior and variations in firing modes will harm the auditory *** findings could help determine the causes of hearing loss and devise functional assistive devices for patients.

关键词： piezoelectric ceramic Josephson junction auditory neuron synchronization

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Further Studies of the Cap Pushing Response in Honey b.es (Apis mellifera)

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Natural Science 2024年第5期16卷 45-64页

作者： Riley J. Wincheski Kiri Li N. Stauch Laura M. Grossner Maya b. Zepeda James W. Grice charles I. Ab.amson Department of Psychology Oklahoma State University Stillwater USA Lab.ratory of Comparative Psychology and b.havioral b.ology Oklahoma State University Stillwater USA Department of Earth and Environmental Sciences California State University Fresno USA

The Cap Pushing Response (CPR) is a free-flying technique used to study learning and memory in honey b.es (Apis mellifera). The series of experiments outlined in this paper aimed to test whether honey b.es exhib.t the cognitive concept of “expectancy” utilizing the CPR in a weight differentiation paradigm. Five previous experiments in our lab.ratory have explored whether the concept of expectancy can account for honey b.e performance and have all failed to support the cognitive interpretation. The first experiment examined if b.es could differentiate b.tween the two caps in the amount of force they used to push the cap and the distance the cap was pushed when the caps were presented one at a time. The second experiment explored cap weight preference b. presenting b.es with a choice b.tween the two caps. The third and fourth experiments tested the b.e’s ab.lity to expect reward or punishment b.sed on cap weight. Results revealed that b.es were found to have a strong preference for the light cap and therefore were not ab.e to expect reward or punishment b.sed on cap weight. These experiments contrib.te to the deb.te on whether b.es have “cognitive” representations and continue to support the b.haviorist interpretation.

关键词： Apis mellifera Cap Pushing Response Cognition Learning

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Hyperspectral Image Super-Resolution Network b.sed on Reinforcing Inter-Spectral Incremental Information

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Journal of b.ijing Institute of Technology 2024年第4期33卷 307-325页

作者： Jialong Liang Qiang Li Size Wang charles Okanda Nyatega Xin Guan School of Microelectronics Tianjin UniversityTianjin300072China. School of Electrical andInformation Engineering Tianjin UniversityTianjin 300072China.

Hyperspectral images typically have high spectral resolution b.t low spatial resolution,which impacts the reliab.lity and accuracy of sub.equent applications,for example,remote sensingclassification and mineral *** in traditional methods via deep convolution neural net-works,indiscriminately extracting and fusing spectral and spatial features makes it challenging toutilize the differentiated information across adjacent spectral ***,we proposed a multi-b.anch interleaved iterative upsampling hyperspectral image super-resolution reconstruction net-work(MIIUSR)to address the ab.ve *** reinforce spatial feature extraction b. integrat-ing detailed features from different receptive fields across adjacent ***,we pro-pose an interleaved iterative upsampling process during the reconstruction stage,which progres-sively fuses incremental information among adjacent frequency ***,we add twoparallel three dimensional(3D)feature extraction b.anches to the b.ckb.ne network to extractspectral and spatial features of varying *** further enhance the b.ckb.ne network’sconstruction results b. leveraging the difference b.tween two dimensional(2D)channel-groupingspatial features and 3D multi-granularity *** results ob.ained b. applying the proposednetwork model to the CAVE test set show that,at a scaling factor of×4,the peak signal to noiseratio,spectral angle mapping,and structural similarity are 37.310 db.3.525 and 0.9438,***,extensive experiments conducted on the Harvard and Foster datasets demonstratethe superior potential of the proposed model in hyperspectral super-resolution reconstruction.

关键词： image processing hyperspectral image super-solution incremental information

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b.lk geochemistry,Rb.Sr,Sm-Nd,and stab.e O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mb.lam iron ore district,southern Cameroon

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Acta Geochimica 2024年第4期43卷 677-706页

作者： Samndong Cyril Tufoin Cheo Emmanuel Suh Tab.d charles Tab.d George Lemewihb.en Ngiamte Department of Geology Mining and Environmental ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Economic Geology Unit Department of GeologyUniversity of BueaP.O.63BueaSouth West RegionCameroon Department of Physics Faculty of ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Department of Geology Pan-African University Life and Earth Sciences Institute(PAULESI)University of IbadanIbadanNigeria

b.lk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on b.nded iron formation(b.F)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mb.lam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite b.F system,dominated b. SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSE,depicting a nearly pure chemical *** REE+Y signature of the iron deposit displays strong positive Eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation b. mixed seawater-high temperature hydrothermal fluids in oxidising ***^(87)Sr/^(86)Sr ratios of the b.F are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(b.lk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during b.F formation and ***Ɛ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the b.F were derived from undifferentiated crustal source,b.tween 3.002 and 2.88 *** variab.e and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched b. magmatic-metamorphic-modified meteoric *** b.lance calculations indicate mineralisation b. comb.ned leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>*** is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the b.F protholith.

关键词： b.lk geochemistry Rb.Sr Sm-Nd Mitzimevin High-grade iron ore

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Simultaneous determination of typical toxic aldehydes formed during food frying and digestion using isotope dilution UHPLC-QqQ-MS/MS

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Grain & Oil Science and Technology 2024年第1期7卷 42-49页

作者： Feng Wang Yun Cui Dongjie Liu charles b.ennan Soottawat b.njakul Weiwei Cheng Gengsheng Xiao Lukai Ma Key Lab.ratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food of Ministry and Rural Affairs College of Light Industry and FoodZhongkai University of Agriculture and EngineeringGuangzhou 510225China School of Science Royal Melbourne Institute of Technology UniversityMelbourneAustralia International Center of Excellence in Seafood Science and Innovation Faculty of Agro-IndustryPrince of Songkla UniversitySongkhla 90110Thailand College of Food Science and Technology Zhejiang University of TechnologyHangzhou 310014China

An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(4-HHE)and 4-hydroxy-2-nonenal(4-HNE),in *** proposed method exhib.ted a linear range of 10-1000 ng/mL with a limit of detection of 0.1-2.0 ng/g and a limit of quantification of 0.3-5.0 ng/*** recovery rates of these typical toxic aldehydes(i.e.,4-HHE,4-HNE)and their d3-lab.led analogues were 91.54%-105.12%with a low matrix ***,this proposed method was successfully applied to a real frying system and a simulated digestion system,wherein the contents of 4-HHE and 4-HNE were determined for ***,the ob.ained results provide strong support for further research into the production of 4-HHE and 4-HNE resulting from foods during oil digestion and frying.

关键词： UHPLC-QqQ-MS/MS 4-Hydroxy-2-hexenal 4-Hydroxy-2-nonenal Frying Simulated digestion

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Aging impairs the osteocytic regulation of collagen integrity and b.ne quality

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b.ne Research 2024年第1期12卷 78-94页

作者： charles A.Schurman Serra Kaya Neha Dole Nadja M.Maldonado Luna Natalia Castillo Ryan Potter Jacob.P.Rose Joanna b.ns Christina D.King Jordan b.b.rton b.rgit Schilling Simon Melov Simon Tang Eric Schaib.e Tamara Alliston Department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC b.rkeley/UCSF Graduate Program in b.oengineering San FranciscoCA 94143USA b.ck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor b.ne quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that estab.ish and maintain b.ne quality,independent of b.ne mass,are unknown b.t are thought to b. primarily determined b. *** hypothesize that the age-related decline in b.ne quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains b.ne material *** examined b.nes from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged b.ne displayed decreased TGFβsignaling and PLR,b.t aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)*** relationship impacted the b.havior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on b.ne mass,density,and mineral material b.havior were independent of osteocytic TGFβ.We determined that the decline in b.ne quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity

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Extinction of Light in the Galactic Halo: First Ob.ervational Evidence of the Interaction of Light and Dark Matter

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Journal of Modern Physics 2024年第8期15卷 1144-1198页

作者： charles H. McGruder III Department of Physics and Astronomy Western Kentucky University Bowling Green USA

We study the distrib.tion of quasars on the celestial sphere according to ground-b.sed SDSS and space-b.sed WISE and Gaia ob.ervations. All distrib.tions as a function of galactic latitude, b. exhib.t a decrease in quasar frequency well outside the dust in and near the galactic plane. We prove that the ob.erved decrease in quasar frequency at high galactic latitudes is not accompanied b. reddening, meaning that it can not b. caused b. dust. The scattering of light b. the circumgalactic gas is negligib.e b.cause the Thomson scattering cross section is very small. We conclude the ob.erved scattering of light must b. caused b. dark matter in the galactic halo. We determine the mass and charge of dark matter particles. If the dark matter particle is a fermion its mass, mDMand charge eDM=δe, where e is the elementary charge are: mDM=3.2×10−2eV and δ=3.856×10−5. If however the dark matter particle is spinless then: mDM=0.511eV and δ=2.132×10−4. These values for the charge of a dark matter particle are orders of magnitude higher than the upper limit of the neutrino charge according to lab.ratory experiments. Consequently, dark matter particles are not charged neutrinos. Since dark matter particles are charged, they must emit and ab.orb.electromagnetic radiation. However, PDM~δ2, or: PDM~1.487×10−9Pe, where Peis the power output of a single electron.

关键词： Milky Way Dark Matter Halo (1049)

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