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Supporting people with depression and anxiety: a guide for practice nurses
This guide has been devleoped for GP practice nurses following a three year research study called ProCEED (Proactive care and its evaluation for enduring depression), conducted by Dr Marta Buszewicz and a research team at University College London
Analysis of antioxidant enzyme activity during reproductive stages of barley under drought stress
Drought is especially considered as key stress factor with high potential impact on crop yield. Plants mainly adapt to water deficits by alteration in physiological and biochemical processes. A simulation experiment on the responses of barley (Hordeum Vulgare L.) from heading stage to ripening stage for different soil water levels (full water supply, light water stress, and severe water stress) was conducted to determine the effects on leaf water status, levels of chlorophyll and protein, lipid peroxidation and antioxidant enzymes activity. The results indicated that drought stress relied on drought intensity and developmental stage, with more severe drought stress creating more serious effects on barley. Relative water content (RWC) significantly decreased (P < 0.05) under drought stress in all stages. The content of soluble protein and chlorophyll decreased and membrane lipid peroxidation (measured as malondialdehyde content) increased significantly according to the severity of water stress and reproductive stage. Under water stress, the activities of antioxidant enzymes ascorbate peroxidase (APX), catalase (CAT), guaiacol peroxidase (POX) and superoxide dismutase (SOD) in leaves increased sharply in flowering and milking stages, but then declined towards the lately ripening stage. Furthermore, compared with well watered conditions, changes in the activities of POX and SOD were different between light water stress and severe water stress at flowering and milking stages. However, the increases in the levels of malondialdehyde (MDA) during flowering and milking stages showed that the increased activities of antioxidant enzymes may not be enough to prevent the peroxidation of lipid membranes and to scavenge reactive oxygen species (ROS) under drought stress
Disorder-induced superconductivity in ropes of carbon nanotubes
We study the interplay between disorder and superconductivity in a rope of
metallic carbon nanotubes. Based on the time dependent Ginzburg Landau theory,
we derive the superconducting transition temperature T taking into account
the critical superconducting fluctuations which are expected to be
substantially strong in such low dimensional systems. Our results indicate
that, contrary to what is expected, T increases by increasing the amount of
disorder. We argue that this behavior is due to the dynamics of the tubes which
reduces the drastic effect of the local disorder on superconductivity by
enhancing the intertube Josephson tunneling. We also found that T is
enhanced as the effective dimensionality of the rope increases by increasing
the number N of the tubes forming the rope. However, T tends to saturate
for large values of N, expressing the establishment of a bulk three dimensional
(3D) superconducting order.Comment: 9 pages, 4 figur
Winning the Recruiting Challenge: Hiring Diverse and Talented IS Faculty Members
Serving on an IS recruiting committee can be a challenge to most faculty members. In addition to standard committee responsibilities, the IS search committee is strategically important to the department’s mission. Hiring a diverse faculty group provides even more challenges to an already difficult task. Particularly in IS, where qualified women and minority applicants may be difficult to find, the task of the search committee is challenging. This paper provides an overview of the IS search committee process, focusing on strategies for recruiting diverse and talented faculty members. Specific strategies include providing relevant training for the committee members, developing appropriate advertising strategies for the position, including diverse faculty in the composition of the committee, removal of any gender or minority identifiable material before review, and courting the candidate to accept the position. These strategies should lead to an increase in recruiting diverse and qualified IS faculty
Critical properties of an aperiodic model for interacting polymers
We investigate the effects of aperiodic interactions on the critical behavior
of an interacting two-polymer model on hierarchical lattices (equivalent to the
Migadal-Kadanoff approximation for the model on Bravais lattices), via
renormalization-group and tranfer-matrix calculations. The exact
renormalization-group recursion relations always present a symmetric fixed
point, associated with the critical behavior of the underlying uniform model.
If the aperiodic interactions, defined by s ubstitution rules, lead to relevant
geometric fluctuations, this fixed point becomes fully unstable, giving rise to
novel attractors of different nature. We present an explicit example in which
this new attractor is a two-cycle, with critical indices different from the
uniform model. In case of the four-letter Rudin-Shapiro substitution rule, we
find a surprising closed curve whose points are attractors of period two,
associated with a marginal operator. Nevertheless, a scaling analysis indicates
that this attractor may lead to a new critical universality class. In order to
provide an independent confirmation of the scaling results, we turn to a direct
thermodynamic calculation of the specific-heat exponent. The thermodynamic free
energy is obtained from a transfer matrix formalism, which had been previously
introduced for spin systems, and is now extended to the two-polymer model with
aperiodic interactions.Comment: 19 pages, 6 eps figures, to appear in J. Phys A: Math. Ge
Predicting Intermediate Storage Performance for Workflow Applications
Configuring a storage system to better serve an application is a challenging
task complicated by a multidimensional, discrete configuration space and the
high cost of space exploration (e.g., by running the application with different
storage configurations). To enable selecting the best configuration in a
reasonable time, we design an end-to-end performance prediction mechanism that
estimates the turn-around time of an application using storage system under a
given configuration. This approach focuses on a generic object-based storage
system design, supports exploring the impact of optimizations targeting
workflow applications (e.g., various data placement schemes) in addition to
other, more traditional, configuration knobs (e.g., stripe size or replication
level), and models the system operation at data-chunk and control message
level.
This paper presents our experience to date with designing and using this
prediction mechanism. We evaluate this mechanism using micro- as well as
synthetic benchmarks mimicking real workflow applications, and a real
application.. A preliminary evaluation shows that we are on a good track to
meet our objectives: it can scale to model a workflow application run on an
entire cluster while offering an over 200x speedup factor (normalized by
resource) compared to running the actual application, and can achieve, in the
limited number of scenarios we study, a prediction accuracy that enables
identifying the best storage system configuration
Accessibility in the regional CGE framework: the effects of major transport infrastructure investments in Poland
Drug interactions between non-rifamycin antibiotics and hormonal contraception: a systematic review
AbstractObjectiveTo determine whether interactions between non-rifamycin antibiotics and hormonal contraceptives result in decreased effectiveness or increased toxicity of either therapy.Data sourcesWe searched MEDLINE, Embase, clinicaltrials.gov and Cochrane libraries from database inception through June, 2016.Study eligibility criteriaWe included trials, cohort, case-control, and pharmacokinetic (PK) studies in any language addressing pregnancy rates, pharmacodynamics or PK outcomes when any hormonal contraceptive and non-rifamycin antibiotic were administered together versus apart. Of 7291 original records identified, 29 met criteria for inclusion.Study appraisal and synthesis methodsTwo authors independently assessed study quality and risk of bias using the United States Preventive Services Task Force evidence grading system. Findings were tabulated by drug class.ResultsStudy quality ranged from good to poor and addressed only oral contraceptive pills, emergency contraception pills and the combined vaginal ring. Two studies demonstrated no difference in pregnancy rates in women using oral contraceptives with and without non-rifamycin antibiotics. No differences in ovulation suppression or breakthrough bleeding were observed in any study combining hormonal contraceptives with any antibiotic. No significant decreases in any progestin PK parameter occurred during co-administration with any antibiotic. Ethinyl estradiol area under the curve decreased when administered with dirithromycin but no other drug.ConclusionEvidence from clinical and PK outcomes studies does not support the existence of drug interactions between hormonal contraception and non-rifamycin antibiotics. Data are limited by low quantity and quality for some drug classes. Most women can expect no reduction in hormonal contraceptive effect with concurrent use of non-rifamycin antibiotics
Dry Matter Yield, \u3ci\u3ein Vitro\u3c/i\u3e Digestibility, Protein and Fiber Composition of \u27Tifton 9\u27 Bahiagrass (\u3ci\u3ePaspalum notatum\u3c/i\u3e) at Six Maturities
The objective of this research was to evaluate dry matter yield, in vitro digestibility, and the concentrations of protein and cell wall components in \u27Tifton 9’clipped at six maturities. Herbage was cut at the age of 20, 27, 34, 41, 48 and 55 days. The experimental design was a randomized complete block with six trataments (ages) and four replications. Dry matter yield and acid detergent fiber ranged from 188 g m-2, to 593 g m-2 and 386.9 g kg-1 to 375.1 g kg-1 respectively, with the cubic regression model having the best fit (P\u3c 0.05). Concentrations of crude protein decreased linearly (P\u3c 0.05) from 121 to 69 g kg-1. Neutral detergent fiber concentration and “in vitro” digestibility, were not affected (P\u3e 0.05) by maturity, in the range studied. Dry matter yield, digestibility and concentration of fiber components presented values similar to other tropical forages, whereas the crude protein remained above 100.5 g kg-1, only until the 27th day, according to the regression model
Continuous Uniform Finite Time Stabilization of Planar Controllable Systems
Continuous homogeneous controllers are utilized in a full state feedback setting for the uniform finite time stabilization of a perturbed double integrator in the presence of uniformly decaying piecewise continuous disturbances. Semiglobal strong Lyapunov functions are identified to establish uniform asymptotic stability of the closed-loop planar system. Uniform finite time stability is then proved by extending the homogeneity principle of discontinuous systems to the continuous case with uniformly decaying piecewise continuous nonhomogeneous disturbances. A finite upper bound on the settling time is also computed. The results extend the existing literature on homogeneity and finite time stability by both presenting uniform finite time stabilization and dealing with a broader class of nonhomogeneous disturbances for planar controllable systems while also proposing a new class of homogeneous continuous controllers
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