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How plants grow up

Journal of Integrative Plant Biology 2019年第3期61卷 257-277页

作者： sarah m mcKim Division of Plant Sciences University of Dundee at The James Hutton Institute

A plant's lateral structures, such as leaves,branches and flowers, literally hinge on the shoot axis,making its integrity and growth fundamental to plant *** all plants, subapical proliferation within the shoot tip displaces cells downward to extrude the cylindrical *** the transition to flowering, many plants show extensive axial elongation associated with increased subapical proliferation and expansion. However, the cereal grasses also elongate their stems, called culms, due to activity within detached intercalary meristems which displaces cells upward, elevating the grain-bearing inflorescence. Variation in culm length within species is especially relevant to cereal crops, as demonstrated by the high-yielding semi-dwarfed cereals of the Green Revolution. Although previously understudied, recent renewed interest the regulation of subapical and intercalary growth suggests that control of cell division planes,boundary formation and temporal dynamics of differentiation, are likely critical mechanisms coordinating axial growth and development in plants.

关键词： plants grow up^FA lateral structures

Comprehension of functional support by enculturated chimpanzees Pan troglodytes

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Current Zoology 2011年第4期57卷 429-440页

作者： Anna m. YOCOm sarah T. BOYSEN Department of Psychology The Ohio State University Columbus OH 43210 USA

Studies of causal understanding of tool relationships in captive chimpanzees have yielded disparate findings, particularly those reported by Povinelli ＆ colleagues （2000） for tool tasks by laboratory chimpanzees. The present set of experiments tested nine enculturated chimpanzees on three versions of a support task, as described by Povinelli （2000）, during which food re- wards were presented in different experimental configurations. In Experiment 1, stimulus pairs included a choice between a cloth with a reward on the upper right comer or with a second reward off the cloth, adjacent to a comer, with the second pair comprised of a cloth with food on the upper right comer, and a second cloth with the reward on the substrate, partially covered. All subjects were successful with both test conditions in Experiment 1. In a second study, the experimental choices included one of two possi- ble correct options, paired with one of three incorrect options, with the three incorrect choices all involving varying degrees of perceptual containment. All nine chimpanzees scored significantly above chance across all six conditions. In Experiment 3, four unique conditions were presented, combining one of two possible correct choices with one of two incorrect choices. Six of the subjects scored significantly above chance across the four conditions, and group performance on individual conditions was also significant. Superior performance was demonstrated by female subjects in Experiment 3, similar to sex differences in tool use previously reported for wild chimpanzees and some tool tasks in captive chimpanzees. The present results for Experiments 2 ＆ 3 were significantly differed from those reported by Povinelli et al. （2000） for laboratory-born, peer-reared chimpanzees. One contribution towards the dramatic differences between the two study populations may be the significant rearing and housing differences of the chimpanzee groups. One explanation is that under conditions of enculturat

关键词： Chimpanzees Comparative cognition Tool use Causality

metabolite Transporter Regulation of ABA Function and Guard Cell Response

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molecular Plant 2014年第10期7卷 1505-1507页

作者： Yunqing Yu sarah m. Assmann Biology Department Pennsylvania State University 208 Mueller Laboratory University Park PA 16802–5301 USA

Pairs of guard cells form stomatal pores through which gas exchange occurs. Gas exchange includes transpirational water loss, and guard cell signaling in drought response has been studied for decades. Abscisic acid （ABA） is the major hormone that regulates drought responses. ABA and other metabolites can be synthesized in one cell type or subcellular compartment and transported across mem- branes by specific transporters to conduct biological func- tions. Two new papers, both taking advantage of reverse genetic methods, one focusing on a plasma membrane ABA efflux carrier （Zhang et al., 2014） and the other on a putative mitochondrial pyruvate carrier （Li et al., 2014）, have recently shown the importance of metabolite trans- porters in ABA function and guard cell response.

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matrix interactions modulate neurotrophin-mediated neurite outgrowth and pathfinding

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Neural Regeneration Research 2015年第4期10卷 514-517页

作者： Christopher m.madl sarah C.Heilshorn Department of Bioengineering Stanford University Department of materials Science and Engineering Stanford University

Both matrix biochemistry and neurotrophic factors are known to modulate neurite outgrowth and pathifnding; however, the interplay between these two factors is less studied. While previous work has shown that the biochemical identity of the matrix can alter the outgrowth of neurites in response to neurotrophins, the importance of the concentration of cell-adhesive ligands is unknown. Using engineered elastin-like protein matrices, we recently demonstrated a synergistic effect between matrix-bound cell-adhesive ligand density and soluble nerve growth factor treat-ment on neurite outgrowth from dorsal root ganglia. This synergism was mediated by Schwann cell-neurite contact through L1CAm. Cell-adhesive ligand density was also shown to alter the pathifnding behavior of dorsal root ganglion neurites in response to a gradient of nerve growth factor. While more cell-adhesive matrices promoted neurite outgrowth, less cell-adhesive ma-trices promoted more faithful neurite pathifnding. These studies emphasize the importance of considering both matrix biochemistry and neurotrophic factors when designing biomaterials for peripheral nerve regeneration.

关键词： neurotrophic factors cell-adhesive ligands dorsal root ganglia L1CAm nerve growth factor biomaterials elastin-like proteins

microbial community coalescence and nitrogen cycling in simulated mortality decomposition hotspots

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Ecological Processes 2023年第1期12卷 608-624页

作者： sarah W.Keenan Alexandra L.Emmons Jennifer m.DeBruyn Department of Geology and Geological Engineering South Dakota School of Mines and Technology501 East St.Joseph StreetRapidSD 57701USA Department of Anthropology University of TennesseeKnoxvilleTNUSA Department of Biosystems Engineering and Soil Science University of Tennessee2506 E.J.Chapman DriveKnoxvilleTN 37996USA

Background The pulsed introduction of dead plant and animal material into soils represents one of the primary mechanisms for returning organic carbon(C)and nitrogen(N)compounds to biogeochemical *** of animal carcasses provides a high C and N resource that stimulates indigenous environmental microbial communities and introduces non-indigenous,carcass-derived microbes to the ***,the dynamics of the coalesced microbial communities,and the relative contributions of environment-and carcass-derived microbes to C and N cycling are *** test whether environment-derived,carcass-derived,or the combined microbial communities exhibited a greater influence on C and N cycling,we conducted controlled laboratory experiments that combined carcass decomposition fluids and soils to simulate carcass decomposition *** selectively sterilized the decomposition fluid and/or soil to remove microbial communities and create different combinations of environment-and carcass-derived communities and incubated the treatments under three temperatures(10,20,and 30℃).Results Carcass-derived bacteria persisted in soils in our simulated decomposition scenarios,albeit at low *** communities had higher respiration rates at 10 and 30℃ compared to soil or carcass communities ***,at higher temperatures,mixed communities had reduced diversity,but higher respiration,suggesting functional *** communities treatments also provided evidence that carcass-associated microbes may be contributing to ammonification and denitrification,but that nitrification is still primarily carried out by native soil *** Our work yields insight into the dynamics of microbial communities that are coalescing during carcass decomposition,and how they contribute to recycling carcasses in terrestrial ecosystems.

关键词： Carcass decomposition microcosm Nitrogen Carbon Biogeochemical cycling Coalescence

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Differential effects of energy balance on experimentally-induced colitis

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World Journal of Gastroenterology 2012年第7期18卷 627-636页

作者： sarah J mcCaskey Elizabeth A Rondini Ingeborg m Langohr Jenifer I Fenton Department of Food Science and Human Nutrition Michigan State UniversityEast LansingMI 48824United States Department of Pathobiology and Diagnostic Investigation Michigan State UniversityEast LansingMI 48824United States College of Osteopathic medicine Michigan State UniversityEast LansingMI 48824United States

AIm： To characterize the influence of diet-induced changes in body fat on colitis severity in SlVlAD3-/- mice.mETHODS： SmAD3-/- mice （6-8 wk of age） were ran- domly assigned to receive a calorie restricted （30% of control; CR）, control （CON）, or high fat （HF） diet for 20 wk and were gavaged with sterile broth or with Helicobacter hepaticus （H. hepaticus） to induce colitis. Four weeks after infection, mice were sacrificed and the cecum and colons were processed for histological evaluation.RESULTS： Dietary treatment significantly influenced body composition prior to infection （P 〈 0.05）, with CR mice having less （14%±2%） and HF-fed mice more body fat （32% ± 7%） compared to controls （22%±4%）. Differences in body composition were associated with alterations in plasma levels of leptin （HF 〉 CON 〉 CR） and adiponectin （CON 〉 HF 〉/ CR）（P 〈 0.05）. There were no significant differences in colitis scores between CON and HF-fed mice 4 wk post-infection. Consistent with this, differences in proliferation and in- flammation markers （COX-2, iNOS）, and infiltrating cell types （CD3^＋ T lymphocytes, macrophages） were not observed. Unexpectedly, only 40% of CR mice survived infection with H. hepaticus, with mortality observed as early as I wk following induction of colitis.CONCLUSION： Increased adiposity does not influence colitis severity in SmAD3-/- mice. Importantly, caloric restriction negatively impacts survival following pathogen challenge, potentially due to an impaired immune response.

关键词： SmAD3 Colitis Adipokine Obesity Calorierestriction

A new distributed feature selection technique for classifying gene expression data

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International Journal of Biomathematics 2019年第4期12卷 79-109页

作者： sarah m.Ayyad Ahmed I.Saleh Labib m.Labib Computers and Systems Department Faculty of Engineering Mansoura University Mansoura 35511 Egypt

Classification of gene expression data is a pivotal research area that plays a substantial role in diagnosis and prediction of diseases. Generally, feature selection is one of the extensively used techniques in data mining approaches, especially in classification. Gene expression data are usually composed of dozens of samples characterized by thousands of genes. This increases the dimensionality coupled with the existence of irrelevant and redundant features. Accordingly, the selection of informative genes (features) becomes difficult, which badly affects the gene classification accuracy. In this paper, we consider the feature selection for classifying gene expression microarray datasets. The goal is to detect the most possibly cancer-related genes in a distributed manner, which helps in effectively classifying the samples. Initially, the available huge amount of considered features are subdivided and distributed among several processors. Then, a new filter selection method based on a fuzzy inference system is applied to each subset of the dataset. Finally, all the resulted features are ranked, then a wrapper-based selection method is applied. Experimental results showed that our proposed feature selection technique performs better than other techniques since it produces lower time latency and improves classification performance.

关键词： Feature selection gene expression dimensionality reduction microarray data classification distributed learning mathematics Subject Classification

Code Smell Detection Using Whale Optimization Algorithm

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Computers, materials & Continua 2021年第8期68卷 1919-1935页

作者： moatasem m.Draz marwa S.Farhan sarah N.Abdulkader m.G.Gafar Department of Software Engineering Faculty of Computers and InformationKafrelsheikh UniversityKafr ElsheikhEgypt Faculty of Informatics and Computer Science British University in EgyptCairoEgypt Department of Information Systems Faculty of Computers and Artificial IntelligenceHelwan UniversityCairoEgypt Department of Computer Science Faculty of Computers and Artificial IntelligenceHelwan UniversityCairoEgypt Faculty of Computer Studies Arab Open UniversityCairoEgypt Department of Computer Science College of Science and Humanities in Al-SulailPrince Sattam bin Abdulaziz UniversityKharjSaudi Arabia Department of machine Learning and Information Retrieval Faculty of Artificial IntelligenceKafrelsheikh UniversityKafr ElsheikhEgypt

Software systems have been employed in many fields as a means to reduce human efforts;consequently,stakeholders are interested in more updates of their *** smells arise as one of the obstacles in the software *** are characteristics of software source code that indicate a deeper problem in *** smells appear not only in the design but also in software *** smells introduce bugs,affect software maintainability,and lead to higher maintenance *** code smells can be formulated as an optimization problem of finding the best detection *** researchers have recommended different techniques to improve the accuracy of code smell detection,these methods are still unstable and need to be *** research has sought only to discover a few at a time(three or five types)and did not set rules for detecting their *** research improves code smell detection by applying a search-based technique;we use the Whale Optimization Algorithm as a classifier to find ideal detection *** this algorithm,the Fisher criterion is utilized as a fitness function to maximize the between-class distance over the withinclass *** proposed framework adopts if-then detection rules during the software development life *** rules identify the types for both medium and large *** are conducted on five open-source software projects to discover nine smell types that mostly appear in *** proposed detection framework has an average of 94.24%precision and 93.4%*** accurate values are better than other search-based algorithms of the same *** proposed framework improves code smell detection,which increases software quality while minimizing maintenance effort,time,and ***,the resulting classification rules are analyzed to find the software metrics that differentiate the nine code smells.

关键词： Software engineering intelligence search-based software engineering code smell detection software metrics whale optimization algorithm fisher criterion

multimodal alarm behavior in urban and rural gray squirrels studied by means of observation and a mechanical robot

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Current Zoology 2010年第3期56卷 313-326页

作者： sarah R.PARTAN Andrew G FULmER maya A.m.GOUNARD Jake E.REDmOND Hampshire College School of Cognitive Science

Urbanization of animal habitats has the potential to affect the natural communication systems of any species able to survive in the changed environment. Urban animals such as squirrels use multiple signal channels to communicate, but it is un- known how ttrbanization has affected these behaviors. multimodal commtmication, involving more than one sensory modality, can be studied by use of biomimetic mechanical animal models that are designed to simulate the multimodal signals and be pre- sented to animal subjects in the field. In this way the responses to the various signal components can be compared and contrasted to determine whether the multimodal signal is made up of redundant or nonredundant components. In this study, we presented wild gray squirrels in relatively urban and relatively rural habitats in Western massachusetts with a biomimetic squirrel model that produced tail flags and alarm barks in a variety of combinations. We found that the squirrels responded to each unimodal component on its own, the bark and tail flag, but they responded most to the complete multimodal signal, containing both the acoustic and the moving visual components, providing evidence that in this context the signal components are redundant and that their combination elicits multimodal enhancement. We expanded on the results of Partan et al. （2009） by providing data on sig- naling behavior in the presence and absence of conspecifics, suggesting that alarm signaling is more likely if conspecifics are present. We found that the squirrels were more active in the urban habitats and that they responded more to tail flagging in the urban habitats as compared to the rural ones, suggesting the interesting possibility of a multimodal shift from reliance on audio to visual signals in noisier more crowded urban habitats [Current Zoology 56 （3）： 313-326, 2010].

关键词： Alarm behavior Communication Gray squirrel Sciurus carolinensis multisensory signaling Redundancy Urbanization Ethorobotics