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The present article introduced a novel idea for information hiding namely steganography. We have used new notions for the construction of the nonlinear component for block cipher based on inverse LA-semigroups. This nonlinear component fundamentally provides confidentiality in the proposed steganographic algorithm. The construction of the algorithm is fundamentally twofold. Firstly, we have constructed a novel scheme to design confusion component namely substitution box (S-box). Secondly, we have utilized the anticipated nonlinear component in digital steganography. The suggested algorithm is tested for different standard digital images. The authentication of the proposed algorithm is confirmed through statistical analysis.

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Objective: The authors sought to evaluate the association of self-efficacy with objective measures of cardiac function, subsequent hospitalization for heart failure (HF), and all-cause mortality. Design: Observational cohort of ambulatory patients with stable CHD. The authors measured self-efficacy using a published, validated, 5-item summative scale, the Sullivan Self-Efficacy to Maintain Function Scale. The authors also performed a cardiac assessment, including an exercise treadmill test with stress echocardiography. Main Outcome Measures: Hospitalizations for HF, as determined by blinded review of medical records, and all-cause mortality, with adjustment for demographics, medical history, medication use, depressive symptoms, and social support. Results: Of the 1,024 predominately male, older CHD patients, 1013 (99%) were available for follow-up, 124 (12%) were hospitalized for HF, and 235 (23%) died during 4.3 years of follow-up. Mean cardiac self-efficacy score was 9.7 (SD 4.5, range 0–20), corresponding to responses between “not at all confident” and “somewhat confident” for ability to maintain function. Lower self-efficacy predicted subsequent HF hospitalization (OR per SD decrease = 1.4, p = .0006), and all-cause mortality (OR per SD decrease = 1.4, p Conclusion: Among patients with CHD, self-efficacy was a reasonable proxy for predicting HF hospitalizations. The increased risk of HF associated with lower baseline self-efficacy was explained by worse cardiac function. These findings indicate that measuring cardiac self-efficacy provides a rapid and potentially useful assessment of cardiac function among outpatients with CHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The effect of metal(Ti,Ni,and Au) electrodes on humidity sensing properties of electrospun TiO2 nanofibers was investigated in this work.The devices were fabricated by evaporating metal contacts on SiO2 layer thermally grown on silicon substrate.The separation between the electrodes was 90μm for all sensors.The sensors were tested from 40%to 90%relative humidity(RH) by AC electrical characterization at room temperature. When sensors are switched between 40%and 90%RH,the corresponding response and recovery time are 3 s and 5 s for Ti-electrode sensor,4 s and 7 s for Ni-electrode sensor,and 7 s and 13 s for Au-electrode sensor.The hysteresis was 3%,5%and 15%for Ti-,Ni-,and Au-electrode sensor,respectively.The sensitivity of Ti,Ni,and Au-electrode sensors are 7.53 MΩ/%RH,5.29 MΩ/%RH and 4.01 MΩ/%RH respectively at 100 Hz.Therefore Ti-electrode sensor is found to have linear response,fast response and recovery time and higher sensitivity as compared with those of Ni- and Au-electrode sensors.Comparison of humidity sensing properties of sensors with different electrode material may propose a compelling route for designing and optimizing humidity sensors.  相似文献   
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Microbial-catalyzed biotransformations have considerable potential for the generation of an enormous variety of structurally diversified organic compounds, especially natural products with complex structures like triterpenoids. They offer efficient and economical ways to produce semi-synthetic analogues and novel lead molecules. Microorganisms such as bacteria and fungi could catalyze chemo-, regio- and stereospecific hydroxylations of diverse triterpenoid substrates that are extremely difficult to produce by chemical routes. During recent years, considerable research has been performed on the microbial transformation of bioactive triterpenoids, in order to obtain biologically active molecules with diverse structures features. This article reviews the microbial modifications of tetranortriterpenoids, tetracyclic triterpenoids and pentacyclic triterpenoids.  相似文献   
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The search for alternative energy sources is presently at the forefront of applied research. In this context, thermoelectricity for direct energy conversion from thermal to electrical energy plays an important role. This paper is concerned with the development of highly efficient p-type Ge x Pb1−x Te alloys for thermoelectric applications, using spark plasma sintering. The carrier concentration of GeTe was varied by alloying of PbTe and/or by Bi2Te3 doping. Very high ZT values up to ~1.8 at 500°C were obtained by doping Pb0.13Ge0.87Te with 3 mol% Bi2Te3.  相似文献   
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BACKGROUND: Patients with chronic idiopathic constipation can be difficult to manage either medically or surgically. We report our experience of long-term follow-up of 21 patients who had undergone colectomy with ileorectal anastomosis for difficult chronic idiopathic constipation. METHODS: The patients (19 female, 2 male) were aged 26-68 (median = 46) years and had undergone subtotal colectomy 5-12 (median = 8) years before their assessment. They answered a questionnaire about severity of abdominal pain, bloating, urgency, and straining. They also completed the hospital anxiety and depression questionnaire. Fifteen ulcerative colitis patients with panproctocolectomy and 13 colon cancer patients with colonic resection who had a similar follow-up period served as control groups. The following assessments were performed in chronic idiopathic constipation patients with subtotal colectomy: a) oesophageal manometry; b) scintigraphic gastric emptying test; c) review of barium follow-through; d) glucose H2 breath test; e) urodynamic studies; and f) autonomic function tests. RESULTS: Twenty-four per cent of patients with chronic idiopathic constipation had a family history of difficult constipation requiring hospital investigations and treatment. At the time of assessment abdominal pain, bloating, urgency, and straining at defecation were all significantly more frequent in patients with chronic idiopathic constipation with colectomy than in the control groups with colectomy. Seventy-one per cent of chronic idiopathic constipation patients had at least one episode of intestinal obstruction after subtotal colectomy, which is significantly higher (P < 0.01) than in the control groups (ulcerative colitis, 13%; colonic carcinoma, 8%). In patients with chronic idiopathic constipation, among those studied, 68% had some oesophageal motor dysfunction: 19% delayed gastric emptying; 10%, prolonged small-bowel transit on barium follow-through; 54%, abnormal urodynamic variables; and 14%, abnormal autonomic function tests. CONCLUSIONS: This study shows considerable morbidity in a selected cohort of patients with chronic idiopathic constipation who were sufficiently disabled by their symptoms to undergo subtotal colectomy. They had more abdominal and rectal symptoms and more frequent intestinal obstructive episodes than control groups with colonic resection. Evidence of generalized smooth-muscle dysfunction and familial occurrence of constipation suggests a primary chronic intestinal pseudo-obstruction-like disorder in some of these patients.  相似文献   
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Emotion recognition from facial images is considered as a challenging task due to the varying nature of facial expressions. The prior studies on emotion classification from facial images using deep learning models have focused on emotion recognition from facial images but face the issue of performance degradation due to poor selection of layers in the convolutional neural network model.To address this issue, we propose an efficient deep learning technique using a convolutional neural network model for classifying emotions from facial images and detecting age and gender from the facial expressions efficiently. Experimental results show that the proposed model outperformed baseline works by achieving an accuracy of 95.65% for emotion recognition, 98.5% for age recognition, and 99.14% for gender recognition.

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50.
Ali  Sadia  Hafeez  Yaser  Hussain  Shariq  Yang  Shunkun 《Software Quality Journal》2020,28(2):397-423
Software Quality Journal - To survive in competitive marketplaces, most organizations have adopted agile methodologies to facilitate continuous integration and faster application delivery and rely...  相似文献   
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