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The costs of reproduction in plants cannot differ between the sexes

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Journal of Plant Ecology 2022年第6期15卷 1308-1311页

作者： jeremy J.Midgley Department of Biological Sciences University of Cape TownCape TownSouth Africa

This article is a commentary on Liu et al.(2021).In their recent review in this journal,Liu et al.(2021)argue that sexual differences in the allocation to reproduction by male and female plants may cause sexual differences in their responses to biotic(***)and abiotic stress(*** stress).Their general argument is that the nett reproductive costs are higher for females because they not only flower but must also produce fruits/cones/seeds(their Figure 3).They suggest(their Figure 2)that females can ameliorate their higher costs of reproduction such as by maximizing resource acquisition and resource *** other previous reviews have also argued for higher female costs(Barrett and Hough 2013;Barrett et al.2010;Juvany and Munné-Bosch 2015;Obeso 2002).My aims in this commentary are(i)to note that theory predicts equal sexual allocation to reproduction,(ii)to argue that some of examples cited by Liu et al.(2021)do not suggest the theory is incorrect and finally,(iii)to provide a Cape(South Africa)perspective to show that differences in allocation cannot be invok.d ad hoc to explain vegetative or other differences between the *** differences between the sexes must ultimately be related to differences in sexual function,as is the case in animals,and not to differences in nett allocation to reproduction.

关键词： Figure argument finally

An Example Using Improved Lefschetz Duality

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1269-1274页

作者： Pascal LAMBRECHTS jeremy LANE Donald STANLEY Pascal Lambrechts Institut Mathmatique Universit de Louvain Department of Mathemtics University of Toronto Department of Mathematics and Statistics University of Regina

A theorem of Lambrechts and Stanley is used to find the rational cohomology of the complement of an embedding S^(4n-1)→ S^(2n)× S^m as a module and demonstrate that it is not necessarily determined by the map induced on cohomology by the embedding, nor is it a trivial extension. This demonstrates that the theorem is an improvement on the classical Lefschetz duality.

关键词： Lefschetz duality Embedding Extension problem

COVID-19-2021:A New,Less Predictable Phase of the Pandemic

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China CDC week.y 2021年第7期3卷 125-127页

作者： jeremy Farrar Wellcome Trust

It is just over a year ago that what we now k.ow as coronavirus disease 2019(COVID-19)first emerged in Wuhan,China(1).In twelve short months every village,every city in every continent has been *** of millions of people have been infected and recovered and over two million of people have tragically died from *** reality,many more have lost loved *** we may still be closer to the start of this pandemic than to the end.

关键词： closer COV Wuhan

Concentration–discharge patterns of weathering products from global rivers

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Acta Geochimica 2017年第3期36卷 405-409页

作者： Daniel E.Ibarra Seulgi Moon jeremy k.Caves C.Page Chamberlain k.te Maher Earth System Science Stanford University StanfordCA 94305-4216 USA Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Earth Science ETH Ziirich 8092 Zurich Switzerland Geological Sciences Stanford University StanfordCA 94305-2115 USA

Quantifying the functional relationships relating river discharge and weathering products places k.y constraints on the negative feedback.between the silicate weathering and climate. In this study we analyze the concentration–discharge relationships of weathering products from global rivers using previously compiled time-series datasets for concentrations and discharge from global rivers. To analyze the nature of the covariation between specific discharge and concentrations, we use both a power law equation and a recently developed solute production equation. The solute production equation allows us to quantify weathering efficiency, or the resistance to dilution at high runoff, via the Damk.hler coefficient. These results are also compared to those derived using average concentration–discharge *** the power law exponent and the Damk.hler coefficient increase and asymptote as catchments exhibit increasingly chemostatic behavior, resulting in an inverse relationship between the two parameters. We also show that using thedistribution of average concentration–discharge pairs from global rivers, rather than fitting concentration–discharge relationships for each individual river, underestimates global median weathering efficiency by up to a factor of ～10. This study demonstrates the utility of long time-series sampling of global rivers to elucidate controlling processes needed to quantify patterns in global silicate weathering rates.

关键词： Concentration–discharge Rivers Silicate weathering Solutes

Reliability analysis for mine blast performance based on delay type and firing time

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International Journal of Mining Science and Technology 2018年第2期28卷 195-204页

作者： Silva Jhon Li Lifeng Gernand jeremy M. Department of Mining Engineering University of KentuckyLexingtonKY 40506USA The Pennsylvania State University PA 16802USA

Mining blasts may be defined as the use of explosive charges in a controlled manner by following a tightly controlled timing sequence according to an assigned firing order. Changes of timing between charges may result in an altered firing order and failure of the blasting sequence, which can cause high vibration levels, poor fragmentation, and/or an undesirable rock.mass movement direction. Despite the importance of timing in determining mine blast results, there exists a lack.of methodologies or tools with which to assess performance of a complete blast based on delay type and timing sequence. This document applies reliability engineering principles to evaluate the performance of a mine blast. The analyses are based on test results of the accuracy and precision of electronic and pyrotechnic detonators for typical firing times used in a surface coal mine, but may be applied to a variety of mines and timing scenarios.

关键词： Blast Timing sequence Scatter Reliability Risk analysis Monte Carlo simulation

Spin-preserving chiral photonic crystal mirror

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Light(Science & Applications) 2020年第1期9卷 1787-1798页

作者： Behrooz Semnani jeremy Flannery Rubayet Al Maruf Michal Bajcsy Institute for Quantum Computing(IQC) University of WaterlooWaterloo N2L3G1 ONCanada Department of Electrical&Computer Engineering University of WaterlooWaterloo N2L3G1 ONCanada Department of Physics and Astronomy University of WaterlooWaterloo N2L3G1 ONCanada

Chirality refers to a geometric phenomenon in which objects are not superimposable on their mirror *** made of nanoscale chiral elements can exhibit chiroptical effects,such as dichroism for left-and right-handed circularly polarized light,which mak.s these structures highly suitable for applications ranging from quantum information processing and quantum optics to circular dichroism spectroscopy and molecular *** the same time,strong chiroptical effects have been challenging to achieve even in synthetic optical media,and chiroptical effects for light with normal incidence have been speculated to be prohibited in thin,lossless quasi-two-dimensional ***,we report an experimental realization of a giant chiroptical effect in a thin monolithic photonic crystal *** conventional mirrors,our mirror selectively reflects only one spin state of light while preserving its handedness,with a near-unity level of circular *** operational principle of the photonic crystal mirror relies on guided-mode resonance(GMR)with a simultaneous excitation of leak. transverse electric(TE-lik.)and transverse magnetic(TM-lik.)Bloch modes in the photonic crystal *** modes are not reliant on the suppression of radiative losses through long-range destructive interference,and even small areas of the photonic crystal exhibit robust circular *** its simplicity,the mirror strongly outperforms earlier reported structures and,contrary to a prevailing notion,demonstrates that near-unity reflectivity contrast for opposite helicities is achievable in a quasi-two-dimensional structure.

关键词： mirror crystal circular

A study on joining magnesium alloy high pressure die casting components with thread forming fasteners

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Journal of Magnesium and Alloys 2018年第2期6卷 114-120页

作者： Gerry Gang Wang jeremy Bos Meridian Lightweight Technologies StrathroyOntario N7G 4H6Canada N7G 4H6

With tremendous weight saving potential,magnesium alloy high pressure die casting components have been widely used for automotive *** fastening technology is thus becoming increasingly important to design *** as-cast holes of magnesium high pressure die casting components with thread forming fasteners provides significant advantages for the assembly process,overall cost benefit and joint *** type of joint is thus preferred for structural *** the thread forming fasteners with as-cast holes follows the general rules for designing for the machined holes,including carefully designing the variables such as the assembly torque range,the length of thread engagement,the hole diameter and required failure *** addition,special attention needs to be paid to the draft angles of the magnesium cast components that are required for the die casting *** this paper,the effects of above k.y factors,individually and combined,on the joint performance of thread forming fasteners with as-cast blind holes of AM60B magnesium components are studied.A joint design philosophy was proposed to optimize both joint performance(the prevailing torque,the failure torque and the failure mode)and manufacturing easiness(the hole diameter and corresponding draft angle).The detailed design considerations for as-cast holes of magnesium HPDC are discussed and explained through a hypothetical example.

关键词： Magnesium Die casting Fastening Joining Thread forming.

Single Molecule FRET Study of DNAG Quadruplex

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Chemical Research in Chinese Universities 2002年第2期18卷 103-106页

作者： jeremy Green Liming Ying David k.enerman Shank.r Blasubramanian Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK

The DNA G quadruplex formed by the human telomeric sequence is a potential target for novel anticancer drugs. We have investigated an intramolecular DNA G quadruplex using single molecule fluorescence resonance energy transfer and shown that individual folded quadruplexes can be identified. The mean proximity ratio measured at the single molecule level was consistent with ensemble measurement

关键词： G quadruplex Fluorescence resonance energy transfer(FRET) Single molecule spectroscopy

A Time Neighborhood Method for the Verification of Landfalling Typhoon Track.Forecast

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Advances in Atmospheric Sciences 2023年第2期40卷 273-284页

作者： Daosheng XU jeremy Cheuk.Hin LEUNG Banglin ZHANG Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial k.y Laboratory of Regional Numerical Weather Prediction CMAGuangzhou 510640China

Landfalling typhoons can cause disasters over large *** government and emergency responders need to tak. measures to mitigate disasters according to the forecast of landfall position,while slight timing error can be *** reliability of operational model forecasts of typhoon landfall position needs to be evaluated beforehand,according to the forecasts and observation of historical *** the evaluation of landfalling typhoon track.the traditional method based on point-to-point matching methods could be influenced by the predicted typhoon translation ***,the traditional track.evaluation method may result in a large track.error even if the predicted landfall position is close to *** purpose of this paper is to address the above issue using a simple evaluation method of landfalling typhoon track.forecast based on the time neighborhood *** this new method,the timing error was lessened to highlight the importance of the position error during the landfall of *** properties of the time neighborhood method are compared with the traditional method based on numerical forecast results of 12 landfalling typhoon *** demonstrated that the new method is not sensitive to the sampling frequency,and that the difference between the time neighborhood and traditional method will be more obvious when the moving speed of typhoon is moderate(between 15−30 k. h^(−1)).The time neighborhood concept can be easily extended to a broader context when one attempts to examine the position error more than the timing error.

关键词： time neighborhood method typhoon track landfalling typhoon model evaluation