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Lack of Apparent Receptor Reserve at Postsynaptic 5- HydroxytryptamineA Receptors Negatively Coupled to Adenylyl Cyclase Activity in Rat Hippocampal Membranes
No full textAnthelmintic resistance in horse cyathostomins in Europe: current status and future perspectives
No full textPrevalence of Extended Spectrum Beta-Lactamases among Escherichia coli and Klebsiella spp isolates in Manipal Teaching Hospital, Pokhara, Nepal
No full textABSTRACT Objective: To isolate, identify and phenotypically characterize extended spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella spp in Manipal Teaching Hospital. Methods: Cross sectional study was conducted among E. coli and Klebsiella spp recovered from patients' various samples to establish the prevalence of organisms producing ESBL in Manipal Teaching Hospital, Pokhara, Nepal between October 2011 and April 2012. ESBL production was detected by Clinical laboratory Standards Institute (CLSI) recommendations. Results: E. coli (n=285) and Klebsiella spp (n=55) were isolated from various clinical samples. The specimens were urine 255 (75%), blood 18 (5.3%), pus 48 (14.1%), sputum 17 (5.1%), and body fluid 2 (0.6%). Seventy six (22.4%) were ESBL producing organisms by phenotypic confirmatory test with double disk diffusion method. ESBL group of organisms showed 100% resistance to ampicillin and cefotaxime. All the organisms in this study were 100% sensitive to imipenem and 95.6% sensitive to cefoperazone+sulbactam combination. ESBL producing isolates showed high rate of resistance to ciprofloxacin (90.7%), ceftriaxone (89.4%), ceftazidime (89.4%), cotrimoxazole (90.4%) and norfloxacin (88.1%) as compared to non-ESBL group. Bulgular: Çeşitli klinik örneklerden izole edilen 285 E. coli ve 55 Klebsiella spp (n=55, % 16,2) çalışmaya dahil edildi. Ör-nekler in 255'i (% 75) idrar, 18'i (% 5,3) kan, 48'i (% 14,1) püy, 17'si (% 5,1) balgam ve 2'si (% 0,6) vücut sıvısı idi. Çift disk difüzyon ile yapılan fenotipik konfirmasyon testine göre 76 (% 22.4) izolat GSBL üretiyordu. GSBL üreten mikroorganizmaların hepsi (% 100) ampisilin ve seftriaksona dirençli idi. Çalışmaya dahil edilen izolatların % 100'ü karbapenemlere, % 95,6'sı ise sefaperazon-sulbaktama duyarlı idi. GSBL üreten izolatlar siprofloksasin (% 90,7), seftriakson (% 89,4), seftazidim (% 89,4), kotrimaksazol (% 90,4) ve norfloksasin (% 88,1) GSBL üretmeyen gruba göre daha yüksek oranda dirençli idiler. Conclusion: ESBL producing E. coli and Sonuç: Nepal'de GSBL üreten E. coli and Klebsiella spp. prevalansı yüksek bulundu. Nepal hastanelerinde antibiyotik tedavisinin optimize edilmesi ve GSBL üreten mikroorganizmaların yayılımının engellenmesi için laboratuarda rutin olarak GSBL belirlemeye yönelik testler uygulanmalıdır
Higher-Order Conjugate Gradient Method (HCGM) For Solving Continuous Optimal Control Problems
No full textHeteroclinic Connections between Periodic Orbits in Planar Restricted Circular Three Body Problem -Part II
No full textAbstract We present a method for proving the existence of symmetric periodic, heteroclinic or homoclinic orbits in dynamical systems with the reversing symmetry. As an application we show that the Planar Restricted Circular Three Body Problem (PCR3BP) corresponding to the Sun-JupiterOterma system possesses an infinite number of symmetric periodic orbits and homoclinic orbits to the Lyapunov orbits. Moreover, we show the existence of symbolic dynamics on six symbols for PCR3BP and the possibility of resonance transitions of the comet. This extends earlier results by Wilczak and Zgliczynski[12]
Recent achievements and trends in experimental plant biology
Get PDFAbstract Between 21 and 25 September 2009, Krakow hosted the 4th Conference of the Polish Society of Experimental Plant Biology, co-organized with the Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, and supported by the Biochemical Society. The aim of the conference was to present and discuss the most important topics in different disciplines of plant experimental science as well as to facilitate the interaction and co-operation between scientists. To achieve this goal, about 30 top specialists in various areas of plant biology were invited to give plenary lectures in the following sessions: Plant structure and development; Plant-microbial interactions; Mitochondria and chloroplasts in cell metabolism; Stress tolerance in plants; Structural and functional organization of plant genomes; Mutants in developmental and metabolic studies; Secondary metabolites as pharmaceutics and nutraceutics; Plant membranes; and Integrating plant functions via signalling molecules: molecular mechanisms. Some of the main problems highlighted in the plenary lectures are briefly summarized in the present paper. Two poster sessions enabled a discussion of over 200 posters presented. The conference had an international character, its official language was English, and among the more than 350 participants, about 60 were from abroad. Several plenary lectures were prepared as short review papers and they are published in this issue of Biochemical Society Transactions
How the story unfolds: exploring ways faculty develop open-ended and closed-ended case designs. Adv Physiol Educ 32: 279–285
Get PDFNesbitt LM, Cliff WH. How the story unfolds: exploring ways faculty develop open-ended and closed-ended case designs. Adv Physiol Educ 32: 279-285, 2008; doi:10.1152/advan.90158.2008.-Open-ended or closed-ended case study design schemes offer different educational advantages. Anatomy and physiology faculty members who participated in a conference workshop were given an identical case about blood doping and asked to build either an open-ended study or a closed-ended study. The workshop participants created a rich array of case questions. Participant-written learning objectives and case questions were compared, and the questions were examined to determine whether they satisfied criteria for open or closed endedness. Many of the participant-written learning objectives were not well matched with the case questions, and participants had differing success writing suitable case questions. Workshop participants were more successful in creating closed-ended questions than open-ended ones. Eighty-eight percent of the questions produced by participants assigned to write closed-ended questions were considered closed ended, whereas only 43% of the questions produced by participants assigned to write open-ended questions were deemed open ended. Our findings indicate that, despite the fact that instructors of anatomy and physiology recognize the value of open-ended questions, they have greater difficulty in creating them. We conclude that faculty should pay careful attention to learning outcomes as they craft open-ended case questions if they wish to ensure that students are prompted to use and improve their higher-order thinking skills. case-based learning; learning objectives; convergent questions; divergent questions; questioning CASES are stories with an educational message (7) and have garnered widespread interest among instructors in the biomedical sciences (11). How these stories unfold depends on the ingenuity of the case designer. The best case studies are written to invite students to explore a multitude of intellectual pathways with learning objectives serving as trail markers for the educational journey ahead (2). In the same way that a master storyteller often fashions a tale to have alternate endings, the case author is at liberty to develop case studies in differing directions-narrowing or widening, closing or opening the scope of the study-as pedagogical needs arise. Previously, we have described some of the essential features that distinguish open-ended from closed-ended case study design elements (2). We noted that open-ended case designs permit multiple solutions [i.e., are divergent (3, 13)] since the knowledge needed to solve the case study may be in flux, the necessary information may not be known or available, or certainty cannot be obtained. Alternately, closed-ended designs usually have a single solution [i.e., are convergent (3, 13)] since the knowledge required is well defined and the information needed is readily accessible. We concluded that, depending on the goal for student learning, either type of case approach can yield outcomes that are beneficial for student understanding. Underlying these contentions was the assumption that, starting from the same scenario, case studies can be profitably unfolded along either open-or closed-ended avenues. While our suggestions generate a helpful framework for choosing between open-and closed-ended design schemes, we realized that our thesis would gain greater definition if we demonstrated the construction of actual case studies illustrating the salient features of both types of architectures. Even though we could have produced such case studies on our own, we hypothesized that by helping other faculty members understand the features of open-and closed-ended case studies, we could enable them to generate useful exemplars. So, we asked a group of instructors of anatomy and physiology to fashion open-or closed-ended components of a single case study as they participated in a workshop that highlighted the features and benefits of both open and closed case design. By doing so, we saw the potential to obtain a much richer tapestry of case elements than we could have invented ourselves, and we recognized that we might also be able to uncover some of the adequacies and inadequacies of faculty members as they approach the design process. Thus, we saw the value in carefully examining and reporting the efforts of workshop participants to develop open-and closed-ended features of a single case. Here, we describe on our efforts to 1) solicit from workshop participants their thoughts on the advantages of closed-and open-ended designs and 2) determine how participants would build a case study following either an open-ended approach or a closed-ended approach to case design when starting from an identical case scenario. We chose a short story about blood doping by an Olympic athlete that offered multiple avenues of inquiry, presented a dilemma to be addressed, and was replete with the social, behavioral, and ethical implications of physiology that Penny Hansen has described as a component of the discipline's recondite curriculum (6). Given this scenario, participants were asked to begin developing a case study by creating the design elements, i.e., learning objectives and corresponding case questions, which would guide and stimulate student learning. By examining the products of the participant's work, we intended to examine and analyze the design schemes they used as they created open-or closed-ended approaches to case studies. METHODS Two workshops, entitled "Open-Ended and Closed-Ended Approaches to the Design of Case Studies," were offered as part of the program of the 2002 national meeting of the Human Anatomy and Physiology Society. The workshop participants consisted of ϳ50 anatomy and physiology educators who were interested in the use o
No full textAbstract -The magnetic anomalies due to the interaction of the energy levels of a rare-earth ion in a strong magnetic field are studied experimentally and theoretically for the van-Vleck paramagnet PrVO 4 . A maximum is discovered in the differential susceptibility dM / dH in a field H c ≈ 45 T, where the lower energy levels cross. The magnetocaloric effect in pulsed fields is calculated assuming the magnetization process to be adiabatic. This effect is characterized by the absence of initial heating of the sample when the field is turned on and strong cooling as H c is approached. It is shown that in PrVO 4 , which is an enhanced nuclear magnet, the hyperfine interaction plays an extremely important role for the magnetic anomalies associated with crossover. For another van-Vleck paramagnet, HoVO 4 , it is shown that a second crossover occurs near 310 T and the magnetocaloric effect is calculated
Multi-linear formulation of differential geometry and matrix regularizations
Get PDFAbstract We prove that many aspects of the differential geometry of embedded Riemannian manifolds can be formulated in terms of multi-linear algebraic structures on the space of smooth functions. In particular, we find algebraic expressions for Weingarten's formula, the Ricci curvature, and the Codazzi-Mainardi equations. For matrix analogues of embedded surfaces, we define discrete curvatures and Euler characteristics, and a non-commutative GaussBonnet theorem is shown to follow. We derive simple expressions for the discrete Gauss curvature in terms of matrices representing the embedding coordinates, and explicit examples are provided. Furthermore, we illustrate the fact that techniques from differential geometry can carry over to matrix analogues by proving that a bound on the discrete Gauss curvature implies a bound on the eigenvalues of the discrete Laplace operator
Terramechanics-Based High-Fidelity Dynamics Simulation for Wheeled Mobile Robot on Deformable Rough Terrain
Get PDFAbstract-Numerical simulation analysis of the motion of wheeled mobile robots is significant for both their R&D and control phases, especially due to the recent increase in the number of planetary exploration missions. Using the position/orientation of the rover body and all the joint angles as generalized coordinates, the Jacobian matrices and recursive dynamic models are derived. Terramechanics models for calculating the forces and moments that act on the wheel-as a result of the deformable soil-are introduced in consideration of the effect of normal force. A rough terrain modeling method is developed for estimating the wheel-soil interaction area, wheel sinkage, and the terminal coordinate. A simulation program that includes the above techniques is developed using Matlab and SpaceDyn Toolbox. Experimental results from a 4-wheeled mobile robot moving on Toyoura soft sand are used to verify the fidelity of the simulation. A simulation example of a robot moving on a random rough terrain is also presented. I. INTRODUCTION HE Sojourner rover and Mars Exploration Rovers (MER) have proven the effectiveness of wheeled mobile robots (WMRs) in planetary exploration missions. Future missions will require the robots to traverse over more challenging deformable rough terrain. Dynamic simulation plays an important role in both the R&D and tele-operation phases of WMRs The dynamics of WMRs is primarily composed of two parts: the multi-rigid-body dynamics of the vehicle and the wheel-soil interaction terramechanics, which is intricate but important for improving the fidelity of a simulation. Some This work was supported by the National Natural Science Foundation of China Due to the differences between WMRs and terrestrial vehicles in terms of physical dimension, wheel shape, payload, terrain, running velocity, and control mode, etc., it is necessary to examine the applicability of conventional terramechanics theory and to improve it by targeting WMRs. Yoshida et al. from the Space Robotics Laboratory (SRL) at Tohoku university have been researching terramechanics for planetary exploration robots [9]. The conventional Wong-Reece terramechanics formula was employed to derive an improved practical model for calculating drawbar pull This study greatly improves the fidelity of the simulation platform developed at SRL by embedding high-fidelity terramechanics models and dealing with the contact between deformable rough terrain and different wheels rather than an entire rover. A generalized dynamics model for mobile robots, considering all the external forces and moments that act on the wheels, is deduced in Section II. A high-fidelity driving terramechanics model considering wheel lug effect and slip-sinkage, as well as a steering model are introduced in Section III. Section IV describes the method for estimating the wheel-soil contact area on deformable soil. Section V presents the simulation implementation, experimental validation, and an example. [ ]( Terramechanics-based High-Fidelity Dynamics Simulation for Wheeled Mobile Robot on Deformable Rough Terrain II. GENERALIZED RECURSIVE DYNAMICS MODELING A. Recursive Kinematics and Jacobian Matrices Jacobian matrix for mapping generalized velocities to the end-points; elements, i.e., linear velocities and angular velocities of the body, and joint velocities. Let ae X and ae J denote the velocities of all the wheel-soil interaction points and the corresponding Jacobian matrix: (1) where a X ( 6 1 v n × ) is the velocity vector of all the centroid, J a (