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Science China Chemistry 2014年第10期57卷 1355-1362页

作者： FRIPIAT Joseph G. harris Frank e. Laboratoire de Chimie Théorique Unité de chimie physique théorique et structurale University of NamurRue de Bruxelles Department of Physics University of Utah Quantum Theory Project University of Florida

Building on the pioneering work of Jean-Marie Andre and working in the laboratory he founded, the authors have developed a code called FT-1D to make Hartree-Fock electronic structure computations for stereoregular polymers using ewald-type con- vergence acceleration methods. That code also takes full advantage of all line-group symmetries to calculate only the minimal set of two-electron integrals and to optimize the computation of the Fock matrix. The present communication reports a bench- mark study of the FT-1D code using polytetrafluoroethylene （PTFe） as a test case. Our results not only confirm the algorith- mic correctness of the code through agreement with other studies where they are applicable, but also show that the use of con- vergence acceleration enables accurate results to be obtained in situations where other widely-used codes （e.g., PLH and Crys- tal） fail. It is also found that full attention to the line-group symmetry of the PTFe polymer leads to an increase of between one and two orders of magnitude in the speed of computation. The new code can therefore be viewed as extending the range of electronic-structure computations for stereoregular polymers beyond the present scope of the successful and valuable code Crystal.

关键词： poly(tetrafluoroethylene) band structure Fourier-space Hartree-Fock lattice sum ewaid

Cyclooxygenase-2 and the inflammogenesis of breast cancer

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World Journal of Clinical Oncology 2014年第4期5卷 677-692页

作者： Randall e harris Bruce C Casto Zachary M harris The Ohio State University Comprehensive Cancer Center The Ohio State University College of Medicine Columbus OH 43210-1351 United States College of Medicine and College of Public Health Center of Molecular Epidemiology and Environmental Health The Ohio State University Medical Center Columbus OH 43210-1351 United States

Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that constitutive overexpression of cyclooxygenase-2(COX-2) is a ubiquitous driver of mammary carcinogenesis, and reciprocally, that COX-2 blockade has strong potential for breast cancer prevention and therapy. Key findings include the following:(1) COX-2 is constitutively expressed throughout breast cancer development and expression intensifies with stage at detection, cancer progression and metastasis;(2) essential features of mammary carcinogenesis(mutagenesis, mitogenesis, angiogenesis, reduced apoptosis, metastasis and immunosuppression) are linked to COX-2-driven prostaglandin e2(PGe-2) biosynthesis;(3) upregulation of COX-2 and PGe-2 expression induces transcription of CYP-19 and aromatase-catalyzed estrogen biosynthesis which stimulates unbridled mitogenesis;(4) extrahe-patic CYP-1B1 in mammary adipose tissue converts paracrine estrogen to carcinogenic quinones with mutagenic impact; and(5) agents that inhibit COX-2 reduce the risk of breast cancer in women without disease and reduce recurrence risk and mortality in women with breast cancer. Recent sharp increases in global breast cancer incidence and mortality are likely driven by chronic inflammation of mammary adipose and upregulation of COX-2 associated with the obesity pandemic. The totality of evidence clearly supports the supposition that mammary carcinogenesis often evolves as a progressive series of highly specific cellular and molecular changes in response to induction of constitutive overexpression of COX-2 and the prostaglandin cascade in the "inflammogenesis of breast cancer".

关键词： Breast Cancer Cyclooxygenase-2 Nonsteroidal anti-inflammatory drugs Inflammogenesis estrogen Aromatase

Bone morphogenetic protein-2 gene controls tooth root development in coordination with formation of the periodontium

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International Journal of Oral Science 2013年第2期5卷 75-84页

作者： Audrey Rakian Wu-Chen Yang Jelica Gluhak-Heinrich Yong Cui Marie A harris Demitri Villarreal Jerry Q Feng Mary MacDougall Stephen e harris Department of Periodontics University of Texas Health Science Center at San Antonio Baylor College of Dentistry Texas A&M System University of Alabama School of Dentistry

Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey＇s fibers of the periodontal ligament （PDL）. However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 （Bmp2） in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-eGFP mouse model. Sp7-Cre-eGFP first becomes active at e18 in the first molar, with robust Cre activity at postnatal day 0 （PO）, followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2gene is removed from Sp7＋（Osterix＋） cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC （Nfic）, periostin and α-SMA＋ cells. Third, there is a failure to produce vascular endothelial growth factor A （VeGF-A） in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKOsp7-cre＇eGFe. Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKOsp7-cre＇eGFe. These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation.

关键词： Bmp2 gene cementum dentinogenesis periodontium development root formation

Characterization of a novel murine Sost eRT2 Cre model targeting osteocytes

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Bone Research 2019年第1期7卷 41-53页

作者： Delphine B.Maurel Tsutomu Matsumoto Julian A.Vallejo Mark L.Johnson Sarah L.Dallas Yukiko Kitase Marco Brotto Michael J.Wacker Marie A.harris Stephen e.harris Lynda F.Bonewald Department of Oral and Craniofacial Sciences University of Missouri-Kansas City School of DentistryKansas CityMOUSA Department of Anatomy and Cell Biology Indiana University School of MedicineIndianapolisINUSA Bone.Muscle Collaborative Sciences College of Nursing and Health InnovationUniversity of Texas at ArlingtonArlingtonUSA Department of Biomedical Sciences University of Missouri-Kansas City School of MedicineKansas CityMOUSA University of Texas Health Science Center San AntonioTXUSA Department of Orthopaedic Surgery Indiana University School of MedicineIndianapolisINUSA Pharmaceutical Sciences Department Universite de BordeauxBio-TisINSERM Unité1026 BioTis146 Rue Léo Saignat33076 BordeauxFrance

Transgenic mice are widely used to delete or overexpress genes in a cell specific manner to advance knowledge of bone biology,function and *** numerous Cre models exist to target gene recombination in osteoblasts and osteoclasts,few target osteocytes specifically,particularly mature *** goal was to create a spatial and temporal conditional Cre model using tamoxifen to induce Cre activity in mature osteocytes using a Bac construct containing the 5’and 3’regions of the Sost gene(Sost eRT2 Cre).Four founder lines were crossed with the Ai9 Cre reporter *** founder line showed high and specific activity in mature *** and organs were imaged and fluorescent signal *** no activity was observed in 2 day old pups,by 2 months of age some osteocytes were positive as osteocyte Cre activity became spontaneous or‘leaky’with *** percentage of positive osteocytes increased following tamoxifen injection,especially in males,with 43%to 95%positive cells compared to 19%to 32%in *** signal was observed in any bone surface cell,bone marrow,nor in muscle with or without tamoxifen *** spontaneous signal was observed in any other ***,with tamoxifen injection,a few positive cells were observed in kidney,eye,lung,heart and *** other organs,28 in total,were negative with tamoxifen ***,with age,a muscle phenotype was apparent in the Sost-eRT2 Cre ***,although this mouse model may be useful for targeting gene deletion or expression to mature osteocytes,the muscle phenotype may restrict the use of this model to specific applications and should be considered when interpreting data.

关键词： cell knowledge model

On (t, r) Broadcast Domination of Directed Graphs

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Open Journal of Discrete Mathematics 2022年第3期12卷 78-100页

作者： Pamela e. harris Peter Hollander erik Insko Department of Mathematics and Statistics Williams College Williamstown MA USA Department of Mathematics Florida Gulf Coast University Fort Myers FL USA

A dominating set of a graph G is a set of vertices that contains at least one endpoint of every edge on the graph. The domination number of G is the order of a minimum dominating set of G. The (t, r) broadcast domination is a generalization of domination in which a set of broadcasting vertices emits signals of strength t that decrease by 1 as they traverse each edge, and we require that every vertex in the graph receives a cumulative signal of at least r from its set of broadcasting neighbors. In this paper, we extend the study of (t, r) broadcast domination to directed graphs. Our main result explores the interval of values obtained by considering the directed (t, r) broadcast domination numbers of all orientations of a graph G. In particular, we prove that in the cases r = 1 and (t, r) = (2, 2), for every integer value in this interval, there exists an orientation of G which has directed (t, r) broadcast domination number equal to that value. We also investigate directed (t, r) broadcast domination on the finite grid graph, the star graph, the infinite grid graph, and the infinite triangular lattice graph. We conclude with some directions for future study.

关键词： Directed Domination Directed Broadcasts Finite and Infinite Directed Grid Graphs

Generalizations of the Feline and Texas Chainsaw Josephus Problems

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Open Journal of Discrete Mathematics 2019年第4期9卷 144-158页

作者： David Ariyibi Kevin Chang Pamela e. harris Department of Mathematics and Statistics Williams College Williamstown MA USA

We define and study the extended Feline Josephus Game, a game in which n players, each with ℓlives, stand in a circle. The game proceeds by alternating between hitting k consecutive players—each of whom will consequently lose a life—and skipping s consecutive players. This cycle continues until every player except one loses all of their lives. Given the nonnegative integer parameters n, k, s and ℓ, the goal of the game is to identify the surviving player. In this paper, we show how the defining parameters n, k, s, and ℓaffect the survivor of games with specific constraints on those parameters and our main results provide new closed formulas to determine the survivor of these extended Feline Josephus Games. Moreover, for cases where these formulas do not apply, we provide recursive formulas for reducing the initial game to other games with smaller parameter values. For the interested reader, we present a variety of directions for future work in this area, including an extension which considers players lying on a general graph, rather than on a circle.

关键词： Josephus Game Feline Josephus Game Texas Chainsaw Josephus Game

effects of the shape and size of a mooring line surface buoy on the mooring load of wave energy converters

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Journal of Chongqing University 2012年第1期11卷 1-4页

作者： KRIVTSOV Vladimir LINFOOT Brian harris Robert e. School of Built environment Heriot-Watt UniversityEdinburgh EH14 4ASUnited Kingdom

This paper describes the physical model testing of a wave energy converter (WeC) undertaken in the Heriot-Watt wave basin during October 2010 as part of the SUPeRGeN2 project funded by the British government,and provides a preliminary analysis of the extreme mooring *** were completed at 1/20 scale on a single oscillating water column device deployed with a 3-line taut mooring *** model was fully instrumented with mooring line load cells and an optical motion *** tests were preceded by calibration of instrumentation and the wave test environment,and carried out in long crested waves regimes with 12 combinations of peak period T p and significant wave height H *** main objective for these experiments was to examine the effect of shape and size of the tethered buoy on the leading mooring line on the maximum mooring loads and the excursion of the *** of the loads at different configurations of the tethered buoy suggests that the results are consistent with the hypothesis that the mooring forces should depend on the change in stiffness of the mooring *** particular,the results indicate that with the spectral peak period close to the natural period of the moored device of 8 s,peak loads in a configuration with a smaller buoy may be considerably higher than those with a larger ***,when T p was dissimilar,a harder mooring with a smaller spherical buoy appears to result in lower peak *** exact configuration should,therefore,be chosen according to the prevalent conditions of any particular location,and will also depend on the design and expected maintenance schedule,as well as matters related to the risk to navigation,environmental effects and the conservation status of the area.

关键词： mooring load wave energy converter spherical buoy

Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural Regeneration Research 2025年第3期20卷 803-804页

作者： Glenn A.harris Lauren R.Hirschfeld Rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3R) or 4-repeat(4R) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

Psychiatry Trainees’ Attitudes towards Psychotherapy

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Open Journal of Medical Psychology 2015年第4期4卷 124-130页

作者： Grigore M. Radu Gregory e. harris Weldon Bonnell Krystal Bursey Faculty of Medicine Discipline of Psychiatry Memorial University St. John’s Canada Faculty of education Memorial University St. John’s Canada Department of Psychology Memorial University St. John’s Canada

Background: Psychotherapy education is one of the essential components of specialist training in psychiatry according to the Royal College of Physicians of Canada. How psychiatry trainees perceive psychotherapy has major implications for how trainees will learn about psychotherapy during training, how they will utilize it in their future practice, and how they will integrate it into their professional identity. Methods: The study involved the distribution of questionnaires to psychiatry residents at an Atlantic Canadian Medical School. The survey consisted of Likert-scaled items which assessed residents’ attitudes towards being a psychotherapist and their future study and practice plans in psychotherapy. Results: Surveys were completed by 18 out of 25 residents (72% response rate). Half of participants indicated that conducting psychotherapy was highly rewarding and the majority of residents planned to incorporate psychotherapy into their future practice. Several mean differences were also noted between those residents who completed their undergraduate medical education in Canada versus at International locations. Conclusion: Despite the recent changes in psychotherapy training requirements and concerns about psychotherapy’s role in psychiatry, many residents perceive psychotherapy skills as being important for competent psychiatry practice and plan to incorporate their psychotherapy training into their future practice. Additional implications for teaching, future research, and practice are discussed.

关键词： Psychotherapy Training Psychotherapy Psychiatrists

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