1,851 research outputs found
Comparison of Family 9 Cellulases from Mesophilic and Thermophilic Bacteria
Cellulases containing a family 9 catalytic domain and a family 3c cellulose binding module (CBM3c) are important components of bacterial cellulolytic systems. We measured the temperature dependence of the activities of three homologs: Clostridium cellulolyticum Cel9G, Thermobifida fusca Cel9A, and C. thermocellum Cel9I. To directly compare their catalytic activities, we constructed six new versions of the enzymes in which the three GH9-CBM3c domains were fused to a dockerin both with and without a T. fusca fibronectin type 3 homology module (Fn3). We studied the activities of these enzymes on crystalline cellulose alone and in complex with a miniscaffoldin containing a cohesin and a CBM3a. The presence of Fn3 had no measurable effect on thermostability or cellulase activity. The GH9-CBM3c domains of Cel9A and Cel9I, however, were more active than the wild type when fused to a dockerin complexed to scaffoldin. The three cellulases in complex have similar activities on crystalline cellulose up to 60°C, but C. thermocellum Cel9I, the most thermostable of the three, remains highly active up to 80°C, where its activity is 1.9 times higher than at 60°C. We also compared the temperature-dependent activities of different versions of Cel9I (wild type or in complex with a miniscaffoldin) and found that the thermostable CBM is necessary for activity on crystalline cellulose at high temperatures. These results illustrate the significant benefits of working with thermostable enzymes at high temperatures, as well as the importance of retaining the stability of all modules involved in cellulose degradation
Mott Transition, Compressibility Divergence and P-T Phase Diagram of Layered Organic Superconductors: An Ultrasonic Investigation
The phase diagram of the organic superconductor
-(BEDT-TTF)Cu[N(CN)Cl has been investigated by ultrasonic
velocity measurements under helium gas pressure. Different phase transitions
were identified trough several elastic anomalies characterized from isobaric
and isothermal sweeps. Our data reveal two crossover lines that end on the
critical point terminating the first-order Mott transition line. When the
critical point is approached along these lines, we observe a dramatic softening
of the velocity which is consistent with a diverging compressibility of the
electronic degrees of freedom.Comment: 4 pages, 5 figure
Paper Session III-A - The Advanced Solid Rocket Motor Project
On April 21, 1989, NASA informed Lockheed CEO Dan Tellep that Lockheed Missiles & Space Company had been selected for negotiations of the Advanced Solid Rocket Motor (ASRM). Lockheed Missiles & Space Company, specifically the Missile Systems Division, is the prime contractor to the Marshall Space Flight Center for the ASRM. Teamed with Lockheed as major subcontractors are Aerojet Space Boosters and Rust International as shown in Figure 1. Lockheed Missiles Systems Division\u27s primary function for more than thirty years has been the systems management of major Fleet Ballistic Missile programs for the United States Navy. In those projects, Lockheed subcontractors have been all of the major solid propellant contractors in the United States. Lockheed\u27s role resulting from this experience base is that of project manager, where Lockheed provides systems engineering and integration of the entire project.
Lockheed\u27s association with Aerojet as subcontractor on the Polaris program, dates back to the mid-1950\u27s; thus the ASRM project represents a continuation of a long and productive association between the two major corporations. Aerojet, the major participant in the project, is responsible for the design, analysis and engineering of the rocket motor, as well as the manufacturing, quality assurance and testing. The other major subcontractor to Lockheed is Rust International, headquartered in Birmingham, Alabama. Rust is one of the largest domestic construction companies in the United States and will be responsible for the design and engineering of the facility, procurement and installation of equipment, and managing the construction activities
A 7-year follow-up of sacral anterior root stimulation for bladder control in patients with a spinal cord injury: quality of life and users' experiences\ud
Study design: Cross-sectional descriptive study.\ud
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Objectives: To assess long-term effects and quality of life (QoL) of using sacral anterior root stimulation (SARS) in spinal cord injured patients.\ud
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Setting: Neurosurgical and Urological Departments of a large teaching hospital and a large rehabilitation centre in the Netherlands.\ud
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Methods: In all, 42 patients with complete spinal cord injury (SCI) implanted between 1987 and 2000 were included. A questionnaire was constructed to determine complications, technical failures and personal experiences of the patients. The Qualiveen questionnaire was used and the outcome was compared with data obtained from a reference group of 400 SCI patients with neurogenic bladder problems not using the bladder controller. The Qualiveen questionnaire measures disease-specific aspects in four domains with respect to limitations, constraints, fears and feelings and general QoL aspects, suitable for use in SCI patients with urinary disorders.\ud
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Results: The results of 37 patients are presented. Our results with the bladder controller with respect to medical and technical complications and infection rates are similar to the results presented by others. From users' experiences, the most important advantages reported were a decreased infection rate (68%), improved social life (54%) and continence (54%). Comparison of the obtained results of our patient group with the Qualiveen questionnaire with a reference group not using the bladder controller indicates that the specific impact of urinary disorders in the four domains on QoL is reduced and that general QoL is improved.\ud
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Conclusion: SARS is effective and safe for neurogenic bladder management in patients with complete SCI. Users' experiences are positive. Furthermore, this therapy seems to reduce the effects of urinary-disorder-specific QoL aspects, and to increase the QoL in general\u
New Urbanism: From Exception to Norm—The Evolution of a Global Movement
This thematic issue explores the evolution of the New Urbanism, a normative planning and urban design movement that
has contributed to development throughout the world. Against a dominant narrative that frames the movement as a
straightforward application of principles that has yielded many versions of the same idea, this issue instead proposes an
examination of New Urbanism as heterogeneous in practice, shaped through multiple contingent factors that spell variegated translations of core principles. The contributing authors investigate how variegated forms of New Urbanism emerge,
interrogate why place-based contingencies lead to differentiation in practice, and explain why the movement continues to
be represented as a universal phenomenon despite such on-the-ground complexities. Together, the articles in this thematic
issue offer a powerful rebuttal to the idea that our understanding of the New Urbanism is somehow complete and provide
original ideas and frameworks with which to reassess the movement’s complexity and understand its ongoing impact
Fourier and Gegenbauer expansions for a fundamental solution of the Laplacian in the hyperboloid model of hyperbolic geometry
Due to the isotropy -dimensional hyperbolic space, there exist a
spherically symmetric fundamental solution for its corresponding
Laplace-Beltrami operator. On the -radius hyperboloid model of
-dimensional hyperbolic geometry with and , we compute
azimuthal Fourier expansions for a fundamental solution of Laplace's equation.
For , we compute a Gegenbauer polynomial expansion in geodesic polar
coordinates for a fundamental solution of Laplace's equation on this
negative-constant sectional curvature Riemannian manifold. In three-dimensions,
an addition theorem for the azimuthal Fourier coefficients of a fundamental
solution for Laplace's equation is obtained through comparison with its
corresponding Gegenbauer expansion.Comment: arXiv admin note: substantial text overlap with arXiv:1201.440
Phenomenological model for the remanent magnetization of dilute quasi-one-dimensional antiferromagnets
We present a phenomenological model for the remanent magnetization at low
temperatures in the quasi-one-dimensional dilute antiferromagnets
CH_{3}NH_{3}Mn_{1-x}Cd_{x} Cl_{3}\cdot 2H_{2}O and
(CH_{3})_{2}NH_{2}Mn_{1-x}Cd_{x}Cl_{3}\cdot 2H_{2}O. The model assumes the
existence of uncompensated magnetic moments induced in the odd-sized segments
generated along the Mn(^{2+}) chains upon dilution. These moments are further
assumed to correlate ferromagnetically after removal of a cooling field. Using
a (mean-field) linear-chain approximation and reasonable set of model
parameters, we are able to reproduce the approximate linear temperature
dependence observed for the remanent magnetization in the real compounds.Comment: 5 pages, 2 figures; final version to appear in Physical Review
How does gender influence the recognition of cardiovascular risk and adherence to self-care recommendations? : a study in polish primary care
Background:
Studies have shown a correlation between gender and an ability to change lifestyle to reduce the risk of disease. However, the results of these studies are ambiguous, especially where a healthy lifestyle is concerned. Additionally, health behaviors are strongly modified by culture and the environment. Psychological factors also substantially affect engagement with disease-related lifestyle interventions. This study aimed to examine whether there are differences between men and women in the frequency of health care behavior for the purpose of reducing cardiovascular risk (CVR), as well as cognitive appraisal of this type of risk. We also aimed to identify the psychological predictors of engaging in recommended behavior for reducing the risk of cardiovascular disease after providing information about this risk in men and women.
Methods:
A total of 134 consecutive eligible patients in a family practice entered a longitudinal study. At initial consultation, the individual’s CVR and associated health burden was examined, and preventive measures were recommended by the physician. Self-care behavior, cognitive appraisal of risk, and coping styles were then assessed using psychological questionnaires. Six months after the initial data collection, the frequency of subjects’ self-care behavior was examined.
Results:
We found an increase in health care behavior after providing information regarding the rate of CVR in both sexes; this increase was greater for women than for men. Women followed self-care guidelines more often than men, particularly for preventive measures and dietary advice. Women were more inclined to recognize their CVR as a challenge. Coping style, cognitive appraisal, age, level of health behaviors at baseline and CVR values accounted for 48% of the variance in adherence to self-care guidelines in women and it was 52% in men. In women, total risk of CVD values were most important, while in men, cognitive appraisal of harm/loss was most important.
Conclusions:
Different predictors of acquisition of health behavior are encountered in men and women. Our results suggest that gender-adjusted motivation models influencing the recognition process need to be considered to optimize compliance in patients with CVR
A randomized phase II study of lapatinib + pazopanib versus lapatinib in patients with HER2+ inflammatory breast cancer
This multi-center Phase II study evaluated lapatinib, pazopanib, and the combination in patients with relapsed HER2+ inflammatory breast cancer. In Cohort 1, 76 patients were randomized 1:1 to receive lapatinib 1,500 mg + placebo or lapatinib 1,500 mg + pazopanib 800 mg (double-blind) once daily until disease progression, unacceptable toxicity, or death. Due to high-grade diarrhea observed with this dose combination in another study (VEG20007), Cohort 1 was closed. The protocol was amended such that an additional 88 patients (Cohort 2) were randomized in a 5:5:2 ratio to receive daily monotherapy lapatinib 1,500 mg, lapatinib 1,000 mg + pazopanib 400 mg, or monotherapy pazopanib 800 mg, respectively. The primary endpoint was overall response rate (ORR). Secondary endpoints included duration of response, progression-free survival (PFS), overall survival, and safety. In Cohort 1, ORR for the lapatinib (n = 38) and combination (n = 38) arms was 29 and 45 %, respectively; median PFS was 16.1 and 14.3 weeks, respectively. Grade ≥3 adverse events (AEs) were more frequent in the combination arm (71 %) than in the lapatinib arm (24 %). Dose reductions and interruptions due to AEs were also more frequent in the combination arm (45 and 53 %, respectively) than in the lapatinib monotherapy arm (0 and 11 %, respectively). In Cohort 2, ORR for patients treated with lapatinib (n = 36), lapatinib + pazopanib (n = 38), and pazopanib (n = 13) was 47, 58, and 31 %, respectively; median PFS was 16.0, 16.0, and 11.4 weeks, respectively. In the lapatinib, combination, and pazopanib therapy arms, grade ≥3 AEs were reported for 17, 50, and 46 % of patients, respectively, and the incidence of discontinuations due to AEs was 0, 24, and 23 %, respectively. The lapatinib–pazopanib combination was associated with a numerically higher ORR but no increase in PFS compared to lapatinib alone. The combination also had increased toxicity resulting in more dose reductions, modifications, and treatment delays. Activity with single-agent lapatinib was confirmed in this population
Genetic inhibition of neurotransmission reveals role of glutamatergic input to dopamine neurons in high-effort behavior
Midbrain dopamine neurons are crucial for many behavioral and cognitive functions. As the major excitatory input, glutamatergic afferents are important for control of the activity and plasticity of dopamine neurons. However, the role of glutamatergic input as a whole onto dopamine neurons remains unclear. Here we developed a mouse line in which glutamatergic inputs onto dopamine neurons are specifically impaired, and utilized this genetic model to directly test the role of glutamatergic inputs in dopamine-related functions. We found that while motor coordination and reward learning were largely unchanged, these animals showed prominent deficits in effort-related behavioral tasks. These results provide genetic evidence that glutamatergic transmission onto dopaminergic neurons underlies incentive motivation, a willingness to exert high levels of effort to obtain reinforcers, and have important implications for understanding the normal function of the midbrain dopamine system.Fil: Hutchison, M. A.. National Institutes of Health; Estados UnidosFil: Gu, X.. National Institutes of Health; Estados UnidosFil: Adrover, Martín Federico. National Institutes of Health; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Lee, M. R.. National Institutes of Health; Estados UnidosFil: Hnasko, T. S.. University of California at San Diego; Estados UnidosFil: Alvarez, V. A.. National Institutes of Health; Estados UnidosFil: Lu, W.. National Institutes of Health; Estados Unido
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