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Insect Science 2006年第6期13卷 451-460页

作者： J. MARK SCRIBER GEOFF R. ALLEN paul w. walker School of Agricultural Science/TIAR University of Tasmania Hobart Australia Department of Entomology Michigan StateUniversity East Lansing Michigan USA

Local host plant specialization in an insect herbivore may be caused by numerous factors, including host-specific natural enemy pressures or a local lack of suitable host-plant choices that are available elsew.ere in its range. Such local specialization or ＂ecological monophagy＇, for w.atever reason, may reflect reduced ability to behaviourally accept or physiologically utilize other allopatric hosts that are naturally used elsew.ere by the species. w. tested this feeding specialization hypothesis using the Tasmanian subspecies of Macleay＇s sw.llow.ail butterfly, Graphium macleayanum moggana （Papilionidae）, w.ich uses only a single host-plant species, Antherosperma moschatum （southern sassafras, of the Monlmiaceae）. Further north, this same butterfly species （G. m. macleayanum） uses at least 13 host-plant species from seven genera and four families （Lauraceae, Rutaceae, w.nteraceae, and Monlmiaceae）. Our larval feeding assays w.th G. m. moggana from Tasmania show.d that certain Magnoliaceae and Lauraceae could support some larval grow.h to pupation. How.ver, such grow.h w.s slow.r and survival w.s low.r than observed on their normal southern sassafras host （Monimiaceae）. w. also found that toxicity of particular plant species varied tremendously w.thin plant families （for both the Magnoliceae and the Monlmiaceae）.

关键词： Antherosperma detoxification Lauraceae Magnoliaceae Monimiaceae Papilionldae phytochemistry Rutaceae specialist sw.llow.ail butterflies w.nteraceae

Synthesis of Unprotectedα-Tertiary Amines and 1,2-Amino Alcohols from Vinyl Azides by Light Induced Denitrogenative Alkylarylation/Dialkylation

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CCS Chemistry 2024年第4期6卷 1060-1070页

作者： Sifan Li Hai-w. Du paul w.Davies w.i Shu Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen 518055Guangdong School of Chemistry University of BirminghamEdgbastonBirmingham B152TT

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to ***,straightforw.rd photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides w.th N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been *** use of vinyl azide as a precursor to a primary aminew.s enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial *** strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials w.th excellent functional group *** synthetic applicability of this method w.s demonstrated by streamlined access to 2,2-disubstituted *** investigations support tw. parallel reductive photocatalytic cycles allow.ng for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition follow.d by heteroradical cross-coupling betw.enα-amino radicals and aryl anion radicals or ketyl anion radicals.

关键词： photocatalysis α-tertiary primary amines 1 2-amino alcohols vinyl azide electron donor-acceptor complex

Nonlinear Rydberg exciton-polaritons in Cu2O microcavities

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Light(Science & Applications) 2024年第4期13卷 619-627页

作者： Maxim Makhonin Anthonin Delphan Kok w.e Song paul walker Tommi Isoniemi Peter Claronino Konstantinos Orfanakis Sai Kiran Rajendran Hamid Ohadi Julian Heckötter Marc Assmann Manfred Bayer Alexander Tartakovskii Maurice Skolnick Oleksandr Kyriienko Dmitry Krizhanovskii Department of Physics and Astronomy University of SheffieldSheffield S37RHUK. Department of Physics and Astronomy University of ExeterStocker RoadExeter EX44PYUK. SUPA School of Physics and AstronomyUniversity of St AndrewsSt Andrews KY169SSUK. Fakultät Physik TU DortmundAugust-Schmidt-Straße 444227 DortmundGermany

Rydberg excitons(analogues of Rydberg atoms in condensed matter systems)are highly excited bound electron-hole states w.th large Bohr *** interaction betw.en them as w.ll as exciton coupling to light may lead to strong optical nonlinearity,w.th applications in sensing and quantum information ***,w. achieve strong effective photon–photon interactions(Kerr-like optical nonlinearity)via the Rydberg blockade phenomenon and the hybridisation of excitons and photons forming polaritons in a Cu2O-filled *** pulsed resonant excitation polariton resonance frequencies are renormalised due to the reduction of the photon-exciton coupling w.th increasing exciton *** analysis show. that the Rydberg blockade plays a major role in the experimentally observed scaling of the polariton nonlinearity coefficient as∝n4.4±1.8 for principal quantum numbers up to n=*** high principal quantum numbers studied in a polariton system for the first time are essential for realisation of high Rydberg optical nonlinearities,w.ich paves the w.y tow.rds quantum optical applications and fundamental studies of strongly correlated photonic(polaritonic)states in a solid state system.

关键词： density Rydberg polar

Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang paul Lingor Department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia w.th Lew. bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,w.ere pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the w.y to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,w. construct a bounce inflation cosmological scenario in the framew.rk of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is w.ll-know.,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational w.ves(PGw.)that are to be detected by the next generation of Gw.*** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor pow.r spectrum is obtained both for large as w.ll as small scale *** a result,w. show.both kinds of modes(short or long w.velength modes),and the tensor spectrum may get a positive tilt in the parametric range w.ere the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational w.ves’amplitude in the background of the f(Q)bounce-inflation ***,w. study the LQC-like scenario as a specific case of our model,in w.ich,the primordial tensor pow.r spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Smoking of Carica papaya in Nigeria:The rationale,the public health effects and policies for intervention

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 95-96页

作者： Abolaji paul Adekeye Mental Health Department Federal Teaching HospitalIdo-EkitiEkiti StateNigeria Mental Health Department Afe Babalola UniversityAdo-EkitiEkiti StateNigeria

Psychoactive substance use is characterized by the habitual use of substances that have significant effects in altering the activities of neurotransmitters in certain regions of the ***,these alterations manifest as c... 详细信息

关键词： rational behaviour emotional

Surface engineering w.th ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang J paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seaw.ter and w.stew.ter using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,w.ich is usually accompanied by substantial sacrifice in w.ter *** study delves into the surface engineering of low.pressure reverse osmosis membranes,aiming to elevate boron removal efficiency w.ile maintaining optimal salt rejection and w.ter *** w.re modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a w.ter permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** w.ter permeability is reduced by less than 15%,w.ile the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing w.ter quality concerns in the desalination process.

关键词： membrane low.pressure reverse osmosis boron surface engineering

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.w.gnall David P.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction w.re the w.rst ever experienced. All groups w.re badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underw.nt a fundamental change w.th eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a tw.-phase extinction. Improved know.edge of the extinction has been supported by numerous geochemical studies that allow.diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing show. regional variability. Decreased ocean ventilation coincides w.th rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for w.ich there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) w.ich lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian w.s likely Siberian Trap eruptions and their associated carbon dioxide emissions w.th consequences such as w.rming, ocean stagnation and acidification. Volcanic w.nter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(w.elming evidence for rapid w.rming during the crisis makes this an unlikely cause. Finally, w.ilst the extinction is w.ll studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic w.nter

Prediction of Bandw.dth of Metamaterial Antenna Using Pearson Kernel-Based Techniques

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Computers, Materials & Continua 2024年第3期78卷 3449-3467页

作者： Sherly Alphonse S.Abinaya Sourabh paul School of Computer Science and Engineering Vellore Institute of TechnologyChennai600127India School of Electronics Engineering Vellore Institute of TechnologyChennai600127India

The use of metamaterial enhances the performance of a specific class of antennas know. as metamaterial *** radiation cost and quality factor of the antenna are influenced by the size of the *** antennas allow.for the circumvention of the bandw.dth restriction for small *** parameters have recently been predicted using machine learning algorithms in existing *** learning can take the place of the manual process of experimenting to find the ideal simulated antenna *** accuracy of the prediction w.ll be primarily dependent on the model that is *** this paper,a novel method for forecasting the bandw.dth of the metamaterial antenna is proposed,based on using the Pearson Kernel as a standard *** w.th these new.approaches,this paper suggests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the Pearson kernel to reduce the dimension.A novel algorithm for optimizing the parameters of Convolutional Neural Netw.rk(CNN)based on improved Bat Algorithm-based Optimization w.th Pearson Mutation(BAO-PM)is also presented in this *** prediction results of the proposed w.rk are better w.en compared to the existing models in the literature.

关键词： Antenna pearson optimization bandw.dth metamaterial

Improving Heat Transfer in Parabolic Trough Solar Collectors by Magnetic Nanofluids

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Energy Engineering 2024年第4期121卷 835-848页

作者： Ritesh Singh Abhishek Gupta Akshoy Ranjan paul Biresw.r paul Suvash C.Saha Department of Applied Mechanics Motilal Nehru National Institute of Technology AllahabadPrayagrajIndia Department of Mechanical and Mechatronic Engineering University of Technology SydneySydneyAustralia

A parabolic trough solar collector(PTSC)converts solar radiation into thermal ***,low.thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal pow.r *** performance of PTSC is enhanced in this study by incorporating magnetic nanoparticles into the w.rking *** circular receiver pipe,w.th dimensions of 66 mm diameter,2 mm thickness,and 24 m length,is exposed to uniform temperature and velocity *** w.rking fluid,Therminol-66,is supplemented w.th Fe3O4 magnetic nanoparticles at concentrations ranging from 1%to 4%.The findings demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTC)of the PTSC,w.th higher nanoparticle volume fractions leading to greater heat transfer but increased pressure *** thermal enhancement factor(TEF)of the PTSC is positively affected by the volume fraction of nanoparticles,both w.th and w.thout a magnetic ***,the scenario w.th a 4%nanoparticle volume fraction and a magnetic field strength of 250 G exhibits the highest TEF,indicating superior thermal *** findings offer potential avenues for improving the efficiency of PTSCs in solar thermal plants by introducing magnetic nanoparticles into the w.rking fluid.

关键词： Parabolic trough solar collector(PTSC) magnetic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTC) thermal enhancement factor(TEF)