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Chemical Research in Chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA C. k. j. robert M. C. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with k.own habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification Crystal growth Growth defects

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen robert j.Thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck.et al.,2023). The recent positive results of anti-amyloid trials have brought back.focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Glyoxylate Reductase Isoform 1 is Localized in the Cytosol and Not Peroxisomes in Plant Cells

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j.urnal of Integrative Plant Biology 2012年第3期54卷 152-168页

作者： Steven L. k. Ching Satinder k. Gidda Amanda Rochon Owen R. van Cauwenberghe Barry j. Shelp robert T. Mullen Department of Molecular and Cellular Biology University of Guelph Guelph Ontario N1G 2W1 Canada Department of Plant Agriculture University of Guelph Guelph Ontario N1G 2W1 Canada

Glyoxylate reductase （GLYR） is a k.y enzyme in plant metabolism which catalyzes the detoxification of both photorespiratory glyoxylate and succinic semialdehdye, an intermediate of the γ-aminobutyrate （GABA） pathway. Two isoforms of GLYR exist in plants, GLYR1 and GLYR2, and while GLYR2 is k.own to be localized in plastids, GLYR1 has been reported to be localized in either peroxisomes or the cytosol. Here, we reappraised the intracellular localization of GLYR1 in Arabidopsis thaliana L. Heynh （ecotype Lansberg erecta） using both transiently-transformed suspension cells and stably-transformed plants, in combination with fluorescence microscopy. The results indicate that GLYR1 is localized exclusively to the cytosol regardless of the species, tissue and/or cell type, or exposure of plants to environmental stresses that would increase flux through the GABA pathway. Moreover, the C-terminal tripeptide sequence of GLYR1, -SRE, despite its resemblance to a type 1 peroxisomal targeting signal, is not sufficient for targeting to peroxisomes. Collectively, these results define the cytosol as the intracellular location of GLYR1 and provide not only important insight to the metabolic roles of GLYR1 and the compartmentation of the GABA and photorespiratory pathways in plant cells, but also serve as a useful reference for future studies of proteins proposed to be localized to peroxisomes and/or the cytosol.

关键词： Arabidopsis GABA GLYR1 cytosol photobleaching peroxisome PTS stress tobacco BY-2.

Surgical resection for esophageal carcinoma: Speak.ng the language

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World j.urnal of Gastroenterology 2005年第15期11卷 2211-2212页

作者： robert j. k.rst Division of Thoracic Surgery

The terminology used to describe esophagectomy for carcinoma can be confusing, even for specialists in gastrointestinal disease. As a result, specific terms are often used out of their intended context. To simplify the nomenclature, two points regarding procedures for surgical resection of the esophagus are critical: the extent of resection (radical vs standard) and the operative approach (choice of incisions). It is important to understand that the radicality of the resection may have little to do with the operative approach, with the exception of esophagectomy without thoracotomy (transhiatal esophagectomy), which mandates the performance of a standard or non-radical resection. Esophagectomy has emerged as the standard curative treatment option for patients with esophageal carcinoma; however, unlik. the surgical resection of other types of solid tumors, many different surgical options and/or approaches exist for these patients. This heterogeneity of care may result from the fact that the esophagus is accessible through more than one body cavity (left hemithorax, right hemithorax, abdomen).In addition, and partially as a result of its accessibility,different types of surgical specialists harbor this operation in their armamentarium, including general surgeons,thoracic surgeons, and surgical oncologists. Despite this enthusiasm amongst surgeons, little consensus exists as to which option is most oncologically sound. Further, the details of the various surgical approaches and procedures for resection of the esophagus are often difficult to comprehend, even for specialists in gastrointestinal disease, with much of the relevant terminology used out of its intended context. To facilitate the understanding of the surgical options for esophageal carcinoma, it is useful to view the operation from two angles: the extent of resection (Aradical@ vs Astandard@) and the operative approach (choice of incisions).

关键词： Esophageal carcinoma Terminology

Fluorescence Enhancement Ratio Dropdown at Low Fluences during Femtosecond Double Pulse Laser Ablation

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Chinese Physics Letters 2008年第7期25卷 2653-2656页

作者： Sima SINGHA robert j. GORDON 胡湛 Institute of Atomic and Molecular Physics Jilin University Changchun 130021 Department of Chemistry University of Illinois at Chicago Chicago Illinois 60607-7061 USA

In the study of double pulse ablation of materials （silicon and copper）, a dropdown of double pulse to single pulse fluorescence signal enhancement at low fluences is observed. The dropdown is analysed with a simple theoretical one-dimensional heat diffusion model and verified by fluorescence time constants change as a function of fluence. The dropdown is explained as a result of liquid-solid mixture layer at the liquid and solid boundary. The effect of the layer becomes important at low fluences.

关键词： the power-law exponents precipitation durative abrupt precipitation change

The impact of macroalgae on mean and turbulent flow fields

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j.urnal of Hydrodynamics 2015年第3期27卷 427-435页

作者： THOMAS robert E. MCLELLAND Stuart j. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and maj.r roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

Specifications of Targeting Heterochromatin Modifications in Plants

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Molecular Plant 2018年第3期11卷 381-387页

作者： j.red M. Wendte robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Plants encode a diverse repertoire of DNA methyltransferases that have specialized to target cytosines for methylation in specific sequence contexts. These include the de novo methyltransferase, DOMAINS REARRANGED METHYLTRANSFERASE 2 （DRM2）, which methylates cytosines in all sequence contexts through an RNA-guided process, the CHROMOMETHYLASES （CMTs）, which methylate CHH and CHG cytosines （where H is A, T, or C）, and METHYLTRANSFERASE 1 （MET1）, which maintains methylation of symmetrical CG contexts. In this review, we discuss the sequence specificities and targeting of each of these pathways. In particular, we highlight recent studies that indicate CMTs preferentially target CWG or CWA/CAW motifs （where W is A or T）, and discuss how self-reinforcing feedback.loops between DNA methyltransferases and histone modifications characteristic of heterochromatin specify targeting. Finally, the initiating events that lead to gene body methylation are discussed as a model illustrating how interde- pendent targeting of different silencing pathways can potentiate the establishment of off-target epialleles.

关键词： heterochromatin DNA methylation gene body methylation epiallele DNA methyltransferase,chromomethylase

How spiders practice aggressive and Batesian mimicry

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Current Zoology 2012年第4期58卷 620-629页

作者： Ximena j. NELSON robert R. j.Ck.ON School of Biological Sciences University of Canterbury Private Bag 4800 Christchurch New Zealand International Centre of Insect Physiology and Ecology Thomas Odhiambo Campus EO. Box 30 Mbita Point Kenya

To understand communication, the interests of the sender and the receiver/s of signals should be considered sepa-rately. When our goal is to understand the adaptive significance of specific responses to specific signals by the receiver, questions about signal information are useful. However, when our goal is to understand the adaptive significance to the sender of generating a signal, it may be better to envisage the receiver＇s response to signals as part of the sender＇s extended phenotype. By mak.ng signals, a sender interfaces with the receiver＇s model of the world and indirectly manipulates its behaviour. This is especially clear in cases of mimicry, where animals use deceptive signals that indirectly manipulate the behaviour of receivers. Many animals adopt Batesian mimicry to deceive their predators, or aggressive mimicry to deceive their prey. We review examples from the lite-rature on spiders to illustrate how these phenomena, traditionally thought of as distinct, can become entangled in a web of lies .

关键词： Mimicry Communication Spider Deception Signal Search image

Covering Your Bases： Inheritance of DNA Methylation in Plant Genomes

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Molecular Plant 2014年第3期7卷 472-480页

作者： Chad E. Niederhuth robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Cytosine methylation is an important base modification that is inherited across mitotic and meiotic cell divisions in plant genomes. Heritable methylation variants can contribute to within-species phenotypic variation. Few methylation variants were k.own until recently, mak.ng it possible to begin to address maj.r unanswered questions： the extent of natural methylation variation within plant genomes, its effects on phenotypic variation, its degree of depend- ence on genotype, and how it fits into an evolutionary context. Techniques lik. whole-genome bisulfite sequencing （WGBS） mak. it possible to determine cytosine methylation states at single-base resolution across entire genomes and populations. Application of this method to natural and novel experimental populations is revealing answers to these long-standing questions about the role of DNA methylation in plant genomes.

关键词： DNA methylation epigenetics epiallele whole-genome bisulfite sequencing.

The codewriting work.ook.creating computational architecture in AutoLISP robert j. k.awczyk.; foreword by William j. Mitchell.

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