1,085 research outputs found

    Ab initio molecular dynamics study of manganese porphine hydration and interaction with nitric oxide

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    The authors use ab initio molecular dynamics and the density functional theory+U (DFT+U) method to compute the hydration environment of the manganese ion in manganese (II) and manganese (III) porphines (MnP) dispersed in liquid water. These are intended as simple models for more complex water soluble porphyrins, which have important physiological and electrochemical applications. The manganese ion in Mn(II)P exhibits significant out-of-porphine plane displacement and binds strongly to a single H2O molecule in liquid water. The Mn in Mn(III)P is on average coplanar with the porphine plane and forms a stable complex with two H2O molecules. The residence times of these water molecules exceed 15 ps. The DFT+U method correctly predicts that water displaces NO from Mn(III)P-NO, but yields an ambiguous spin state for the MnP(II)-NO complex.Comment: 10 pages, 6 figure

    Impulse Response with Correlation Study of a Broadband Bended Wearable Monopole Antenna

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    In this paper, the impulse response of a wide band flexible circular monopole antenna is presented. The antenna is fabricated on liquid crystalline polymer flexible substrate with a compact geometry that makes it suitable for wearable applications under different bending conditions. The antenna is fed by coplanar waveguide transmission line and has a compact total size of 40 × 22 mm2. The presented antenna has a good performance over the operating frequency range for straight and bent configurations. The design principals, simulation and experimental results are presented in this work

    Systematic Collective e-Cheating in a Saudi Arabian Higher Education Context: A Case Study

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    Objectives: The primary purpose was to investigate organized group cheating in a Middle Eastern institution during the shift to e-learning brought on by the COVID-19 pandemic in 2019. Method: The study explores the personal experiences of ten Saudi Arabian English as a Foreign Language program graduates in a higher education institution through in-depth interviews via qualitative interpretative phenomenological analysis. The study was guided by Ajzen’s theory of planned behavior. Results: A novel type of misconduct coined systematic collective e-cheating was identified and discussed. In addition, insights on the causes and types of e-cheating in a Middle Eastern context were provided. Conclusions: Academic misconduct was directly influenced by a rapid transition to e-learning, societal culture, and subjective norms, all of which jointly contributed to shifts in ethical perceptions leading to increased reports of cheating. Objectives: The primary purpose was to investigate organized group cheating in a Middle Eastern institution during the shift to e-learning brought on by the COVID-19 pandemic in 2019. Method: The study explores the personal experiences of ten Saudi Arabian English as a Foreign Language program graduates in a higher education institution through in-depth interviews via qualitative interpretative phenomenological analysis. The study was guided by Ajzen’s theory of planned behavior. Results: A novel type of misconduct coined systematic collective e-cheating was identified and discussed. In addition, insights on the causes and types of e-cheating in a Middle Eastern context were provided. Conclusions: Academic misconduct was directly influenced by a rapid transition to e-learning, societal culture, and subjective norms, all of which jointly contributed to shifts in ethical perceptions leading to increased reports of cheating. Implication for Theory and/or Practice: Education professionals need to be aware of underlying issues related to unethical behavior and encourage students to understand and address negative ideologies regarding ethics on a societal level. Efforts must also be made to raise instructor awareness of academic misconduct in e-learning through comprehensive professional development programs. Furthermore, with the increased use of technology in education, if the social, cultural, and perceptional factors are not addressed, educational systems will be impacted, affecting the credibility and value of academic degrees should cheating become the norm

    Evaluation of the Scope, Organization, Effectiveness and Approach of the Work of the United Nations in Mine Action

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    The objectives of the present evaluation are: to provide member States with an independent perspective on the performance of the United Nations in this area, and to inform the development of a new United Nations Inter-Agency Mine Action Strategy for the period 2011-2015. In carrying out the evaluation, the Inspectors looked into the approach, efficiency, effectiveness and coherence of the work of the United Nations in mine action, as set out in the United Nations Inter-Agency Mine Action Strategy for the period 2006-2010 (the Strategy), identified best practices and lessons learned and formulated recommendations with a view to strengthening the work and coordination among United Nations mine action actors

    Generalized ψ

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    The aim of this work is to introduce ψ-operations on fuzzy topological spaces and to use them to study fuzzy generalized ψρ-closed sets and fuzzy generalized ψρ-open sets. Also, we introduce some characterizations and properties for these concepts. Finally we show that certain results of several publications on the concepts of weakness and strength of fuzzy generalized closed sets are considered as corollaries of the results of this research

    Comparison response patterns on landline and cell phone in a call back survey: effects of demographic characteristics and lag days

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    The Asthma Call-back Survey (ACBS) is conducted after the Behavioral Risk Factor Surveillance System (BRFSS) survey by calling BRFSS respondents who reported ever being diagnosed with asthma. To find response patterns and increase ACBS response rates, we first examined whether obtaining consents during the BRFSS survey could increase call back response rates by reducing the refusal and break-off. Then, we assessed how the lag days between BRFSS and ACBS interviews affected response rates. BRFSS cell phone respondents agreed more often to being called back than did landline respondents (75.5 vs. 70.9 percent). However, when respondents were contacted for ACBS, the cell phone response rate was lower than landline response rate (43.4 vs. 47.0 percent), except among males aged 25–34 years, for which the cell phone response rate was 2.1 percent higher than the landline response rate. ACBS response rate for landline and cell phone response were highest if the callback was within 2 days of BRFSS interviews (92.3 vs. 88.8 percent). As lag days increased, the response rate decreased. The cell phone response rate showed a sharper drop; after 2 weeks, the response rate gap between landline and cell phone samples reached 17.3 percent

    Mathematical analysis of HIV/HTLV-I co-infection model with saturated incidence rate

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    Direct contact with specific contaminated body fluids is how both the human immunodeficiency virus (HIV) and the human T-lymphotropic virus type I (HTLV-I) are transmitted from one person to another. Therefore, the two viruses can co-infect same person. In the literature all the HIV/HTLV-I co-infection models assume that the infection rate is given by bilinear incidence. However, for high concentration of pathogens, the bilinear incidence is not suitable. Therefore, this study will focus on the dynamical behavior of an HIV/HTLV-I co-infection model with saturated incidence. The model includes the effect of Cytotoxic T lymphocytes (CTL) immune response. Through the non-negativity and boundedness of the solutions, we demonstrated that our proposed model is biologically acceptable. We calculate the threshold parameters which determine when the equibrium point exists and when it is globally asymptotically stable. Utilizing the Lyapunov function and Lyapunov-LaSalle asymptotic stability, we demonstrate the global asymptotic stability of all equilibrium. We performed numerical simulations to confirm the analytical solutions. The effect of saturation on The dynamics of HIV/HTLV-I co-infection are discussed

    New Insights on Avoiding the Causes of Projects Delays: A Framework

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    In this paper, we study and analyze the reasons behind the delay of some projects. Our aim is shed light on how one reduces the effect of the different obstacles and improves achievement either in quality or time. Different challenges play the main reasons in the stalled project including planning, designing, construction, and weak leaders or poor administrative decisions. We focus on developing a framework that helps in improving the management of the projects and finishing the projects on time. This includes developing a contingency plan and coordination mechanism between internal and external stakeholders. Following the steps of the methodology will help project managers to avoid project delay and solve the problems of the staled ones. Finally, we represent some managerial insights and recommendations that related parties should follow with the projects

    Non-Tensile Tunica Albuginea Plication for the Correction of Penile Curvature

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    Objective: To evaluate the efficacy of non-tensile tunica albuginea plication (NTTAP) using nonabsorbable sutures for the correction of congenital and acquired penile curvature and to determine the key points for a successful outcome of this procedure. Patients and Methods: From June 2004 to July 2007, 43 patients with penile curvature (35 congenital and 8 secondary to Peyronie’s disease) underwent surgical correction by NTTAP. The indications were difficult or impossible vaginal penetration, and a cosmetically unacceptable penis. For tunica albuginea plication (TAP) we applied the 16 dot procedure using non-absorbable sutures (Tycron® 2/0 polyester fiber).Results: After a mean follow-up period of 18 months, successful results with respect to penile straightening, normal erection, penetration and sensation, confirmed both subjectively and objectively, were achieved in all patients. Post-operative penile shortening of less than 1.5 cmwas present in 50% of the cases, but did not affect intercourse. Post-operative complications were mild and reversible; they consisted of penile skin necrosis after circumcising incisions and post-operative pain upon nocturnal erection that subsided after a few weeks with the frequent use of ice compresses. The overall satisfaction rate was nearly 100% (35/43 very satisfied and 8/43 satisfied).Conclusion:NTTAP is a simple and effective method for the correction of congenital and acquired penile curvature. The key points for successful outcomes are: clear identification of the line of maximum curvature, adequate pre-operative evaluation, counseling of the patient to setappropriate expectations, and careful discussion of the location of the suture sites. There is no need for mobilization of the urethra or neurovascular bundle, which adds a great advantage to this easy and simple technique. Cutting through the tunica albuginea, which may prevent postoperative erectile dysfunction, is not necessary. A disadvantage of this procedure is that it cannot correct hour-glass deformity
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