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In the case of Dengue transmission and control, the interaction of nature and society is captured by a system of difference equations. For the purpose of studying the dynamics of these interactions, four variables involved in a Dengue epidemic, proportion of infected people (P), number of mosquitoes involved in transmission (M), mosquito habitats (H), and population awareness (A), are linked in a system of difference equations: Pn+1=aPn+1-e-iMn1-Pn, Mn+1=lMne-An+bHn1-e-Mn, Hn+1=cHn/(1+pAn)+1/(1+qAn), and An+1=rAn+fPn, n=0,1,…. The constraints have socioecological meaning. The initial conditions are such that 0≤P0≤1, (M0,H0,A0)≥(0,0,0), the parameters l,a,c,r∈(0,1), and the parameters f, i, b, and p are positive. The paper is concerned with the analysis of solutions of the above system for p=q. We studied the global asymptotic stability of the degenerate equilibrium. We also propose extensions of the above model and some open problems. We explored the role of memory in community awareness by numerical simulations. When the memory parameter is large, the proportion of infected people decreases and stabilizes at zero. Below a critical point we observe periodic oscillations.

Abstract Pulmonary hypertension (PH) is a progressive and invalidating condition despite available therapy. Addressing complications such as left main coronary artery compression (LMCo) due to the dilated pulmonary artery (PA) may improve symptoms and survival. Nevertheless, clear recommendations are lacking. The aim of this study is to analyze the prevalence, characteristics, predictive factors and impact of LMCo in a heterogenous precapillary PH population in a single referral center. Two hundred sixty‐five adults with various etiologies of precapillary PH at catheterization were reviewed. Coronary angiography (CA) was performed for LMCo suspicion. Revascularization was performed in selected cases. Outcomes were assessed at a mean follow‐up of 3.9 years. LMCo was suspected in 125 patients and confirmed in 39 (31.2%), of whom 21 (16.8%) had 50%–90% stenoses. Nine revascularizations were performed, with clinical improvement. The only periprocedural complication was a stent migration. LMCo was associated with PH etiology (p 0.003), occuring more frequently in congenital heart disease‐associated PH (61.5% of all LMCo cases, 66.6% of LMCo ≥ 50%). Predictors of LMCo ≥50% were PA ≥ 37.5 mm (Sn 81%, Sp 74%) and PA‐to‐aorta ≥1.24 (Sn 81%, Sp 69%), with increased discrimination when considering RV end‐diastolic area. LMCo ≥ 50% without revascularization presented clinical deterioration and worse survival (p 0.019). This analysis of a heterogeneous pre‐capillary PH population provides LMCo prevalence estimation, predictive factors (PA size, PA‐to‐aorta, RV end‐diastolic area and PH etiology) and long‐term impact. While LMCo impact on survival is inconclusive, untreated LMCo ≥ 50% has worse prognosis. LMCo revascularization may be performed safely and with good outcomes.

This review summarizes recent data related to the management of marine plastic litter to promote sustainable development. It discusses the distribution and identification of marine plastic litter, assesses the potential socio-economic and environmental impacts of these pollutants, and explores their recovery strategies, from a circular economy perspective. The main findings indicate that the majority of marine plastic litter originates from land-based sources. Current technologies and approaches for valorizing marine plastic litter include mechanical and chemical recycling, blockchain technologies by providing traceability, verification, efficiency and transparency throughout the recycling process, and public awareness programs and education. The developed policies to prevent marine plastic litter emphasize regulations and initiatives focused toward reducing plastic use and improving plastic waste management. By adopting a holistic and sustainable approach, it is possible to mitigate the environmental impact of marine plastic debris while simultaneously creating economic opportunities.

A comparison was performed between Co-Ni thin films and template-assisted nanowires arrays obtained by electrochemical co-deposition. To reduce the effects of anomalous deposition and increase the Ni content in the deposit, an electrolyte with three times more Ni than Co in atomic ratio was chosen. Electrochemical deposition was performed at constant potentials chosen in the range from E = −0.8 to −1.2 V vs. Ag/AgCl. Cyclic voltammetry, chronoamperometry, and charge stripping techniques were used to characterize and compare the electrochemical behavior of Co-Ni films and nanowires. Morphological and compositional characterization was performed by scanning electron microscopy (SEM/EDAX) to assess the influence of the deposition potential on the growth of film and nanowires. A comprehensive analysis of the deposit growth rates for thin films and nanowires is presented taking into consideration the hydrogen evolution and anomalous deposition. The comparative study of the composition of film and nanowires obtained at different deposition potentials has shown that deposition of nanowires with a film-like composition takes place at more positive potential than thin film.

Microdeletions and microduplications are involved in many of prenatal and postnatal cases of multiple congenital malformations (MCM), developmental delay/intellectual disability (DD/ID), and autism spectrum disorders (ASD). Molecular karyotyping analysis (MCA), performed by DNA microarray technology, is a valuable method used to elucidate the ethology of these clinical expressions, essentially contributing to the diagnosis of rare genetic diseases produced by DNA copy number variations (CNVs). MCA is frequently used as the first-tier cytogenetic diagnostic test for patients with MCM, DD/ID, or ASD due to its much higher resolution (≥10×) for detecting microdeletions and microduplications than classic cytogenetic analysis by G-banded karyotyping. Therefore, MCA can detect about 10% pathogenic genomic imbalances more than G-banded karyotyping alone. In addition, MCA using the Single Nucleotide Polymorphism-array (SNP-array) method also allows highlighting the regions of loss of heterozygosity and uniparental disomy, which are the basis of some genetic syndromes. We presented a case of a five-year-old patient, with global development delay, bilateral fronto-parietal lysencephaly, and pachygyria, for which MCA through SNP-Array led to the detection of the genetic changes, such as 3p26.3p24.3 microduplication and 4q34.3q35.2 microdeletion, which were the basis of the patient's phenotype and to the precise establishment of the diagnosis.

Background: Young gay and bisexual men (YGBM) in some Eastern European countries, such as Romania, face high stigma and discrimination, including in health care. Increasing HIV transmission is a concern given inadequate prevention, travel to high-prevalence countries, and popularity of sexual networking technologies., Objective: This study aimed to adapt and pilot test, in Romania, a preliminarily efficacious mobile health (mHealth) HIV-prevention intervention, created in the United States, to reduce HIV risk among YGBM., Methods: After an intervention formative phase, we enrolled 43 YGBM, mean age 23.2 (SD 3.6) years, who reported condomless sex with a male partner and at least 5 days of heavy drinking in the past 3 months. These YGBM completed up to eight 60-minute text-based counseling sessions grounded in motivational interviewing and cognitive behavioral skills training with trained counselors on a private study mobile platform. We conducted one-group pre-post intervention assessments of sexual (eg, HIV-risk behavior), behavioral (eg, alcohol use), and mental health (eg, depression) outcomes to evaluate the intervention impact., Results: From baseline to follow-up, participants reported significant (1) increases in HIV-related knowledge (mean 4.6 vs mean 4.8; P=.001) and recent HIV testing (mean 2.8 vs mean 3.3; P=.05); (2) reductions in the number of days of heavy alcohol consumption (mean 12.8 vs mean 6.9; P=.005), and (3) increases in the self-efficacy of condom use (mean 3.3 vs mean 4.0; P=.01). Participants reported significant reductions in anxiety (mean 1.4 vs mean 1.0; P=.02) and depression (mean 1.5 vs mean 1.0; P=.003). The intervention yielded high acceptability and feasibility: 86% (38/44) of participants who began the intervention completed the minimum dose of 5 sessions, with an average of 7.1 sessions completed; evaluation interviews indicated that participation was rewarding and an "eye-opener" about HIV risk reduction, healthy identity development, and partner communication., Conclusions: This first mHealth HIV risk-reduction pilot intervention for YGBM in Eastern Europe indicates preliminary efficacy and strong acceptability and feasibility. This mobile prevention tool lends itself to broad dissemination across various similar settings pending future efficacy testing in a large trial, especially in contexts where stigma keeps YGBM out of reach of affirmative health interventions., (©Corina Leluțiu-Weinberger, Monica Manu, Florentina Ionescu, Bogdan Dogaru, Tudor Kovacs, Cristian Dorobănțescu, Mioara Predescu, Anthony Surace, John E Pachankis. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 14.11.2018.)

In this paper, we formulate a nonlinear system of difference equations that models the three-stage life cycle of the deer tick over four seasons. We study the effect of seasonality on the stability and oscillatory behavior of the tick population by comparing analytically the seasonal model with a non-seasonal one. The analysis of the models reveals the existence of two equilibrium points. We discuss the necessary and sufficient conditions for local asymptotic stability of the equilibria and analyze the boundedness and oscillatory behavior of the solutions. A main result of the mathematical analysis is that seasonality in the life cycle of the deer tick can have a positive effect, in the sense that it increases the stability of the system. It is also shown that for some combination of parameters within the stability region, perturbations will result in a return to the equilibrium through transient oscillations. The models are used to explore the biological consequences of parameter variations reflecting expected environmental changes.

We introduce the concept of effective fraction, defined as the expected probability that a configuration from the lowest index replica successfully reaches the highest index replica during a replica exchange Monte Carlo simulation. We then argue that the effective fraction represents an adequate measure of the quality of the sampling technique, as far as swapping is concerned. Under the hypothesis that the correlation between successive exchanges is negligible, we propose a technique for the computation of the effective fraction, a technique that relies solely on the values of the acceptance probabilities obtained at the end of the simulation. The effective fraction is then utilized for the study of the efficiency of a popular swapping scheme in the context of parallel tempering in the canonical ensemble. For large dimensional oscillators, we show that the swapping probability that minimizes the computational effort is 38.74%. By studying the parallel tempering swapping efficiency for a 13-atom Lennard-Jones cluster, we argue that the value of 38.74% remains roughly the optimal probability for most systems with continuous distributions that are likely to be encountered in practice.

We show that the acceptance probability for swaps in the parallel tempering Monte Carlo method for classical canonical systems is given by a universal function that depends on the average statistical fluctuations of the potential and on the ratio of the temperatures. The law, called the incomplete beta function law, is valid in the limit that the two temperatures involved in swaps are close to one another. An empirical version of the law, which involves the heat capacity of the system, is developed and tested on a Lennard-Jones cluster. We argue that the best initial guess for the distribution of intermediate temperatures for parallel tempering is a geometric progression and we also propose a technique for the computation of optimal temperature schedules. Finally, we demonstrate that the swap efficiency of the parallel tempering method for condensed-phase systems decreases naturally to zero at least as fast as the inverse square root of the dimensionality of the physical system., (Copyright 2004 American Institute of Physics)

A favorable effect of laser therapy in rheumatic diseases was demonstrated in a previous paper [9] but it was not possible to estimate whether this benefit was due to an antiinflammatory, analgesic or decontracturant effect. In this work the effect of laser therapy was tested on an experimental inflammation in rats. Laser irradiation reduced the volume of the inflammation during 6 days of treatment more than 85% and prevented the appearance of necrosis. In the control group, the reduction of inflammation was of only 22.86%, the difference vs. the treated group being significant for p = 0.00009, and eight rats of the ten developed local necrosis.

The effect of a 940-980 nm length wave laser radiation in rheumatic degenerative diseases was studied in 136 patients unresponsive to or with contraindications for antiinflammatory non-steroid therapy. The evolution was clinically estimated using four parameters; pain, muscular contracture, local edema and the impairment of the articular mobility. All patients presented a beneficial evolution appearing gradually during the treatment. The osteoarthritis of the knee, ankle and shoulder evolved worse than the painful back. The painful back presented an improved evolution when it was located at the thoracal level. No adverse reaction was observed during this study.