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21.
The natural products are gaining immense importance in the domain of nutrition to prevent various maladies and improve the quality of life. Among these, natural exudates are of significant worth as these biochemical compounds are released by various living entities having pharmacological properties for utilization in various drug developments. These natural exudates are the promising source for the discovery of new medications. Numerous bioactive moieties collected by honeybees from exudates and buds of particular trees and plants, considered to be utilized as defensive barrier with special reference to propolis. It generally contains numerous biochemical components, i.e., polyphenols, steroids, terpenoids, and amino acids. They also contain isoferulic acid, sinapinic acid, caffeic acid, and chrysin responsible for antibacterial perspectives. With special attention to propolis, it has been utilized in folk medicines due to several of its therapeutic activities, i.e., antioxidant, antidiabetic, anti-inflammatory, antiviral, and anticancer properties. In this context, it is extensively used in foodstuffs and beverages to improve health related disorders like inflammation, diabetes, heart disease, protects injured gums, and cancer insurgence. Moreover, it has been used to curtail stomatology, gastroenterology, skin lesions, and otorhinolaryngologic and respiration diseases.  相似文献   
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Secure data transmission over the public channels have high impact and increasingly important due to theft and manipulation in contents. The requirement of public/ private organizations to develop an efficient scheme to provide security to their contents. We developed a digital contents encryption scheme based Arnold scrambling and Lucas series, which is very simple to implement but almost impossible to breach in this article. We perform encryption at standard images by using Lucas series at different iterations of scrambled images of Arnold transform. Numerical simulation analyses performed to analyze the efficiency and effectiveness of the projected structure.

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The objective of this research is to construct a type-II heterojunction interface for effective photoelectrochemical (PEC) water splitting for hydrogen generation. A series of ZnSe/g-C3N4 heterojunctions is prepared by ultrasonication procedure and tested for PEC water splitting for the first time. The successful formation of ZnSe/g-C3N4 is confirmed by phase, morphological and optical analysis. Linear sweep voltammetry of 0.05 ZG (0.05% ZnSe/g-C3N4) showed a six-fold higher photocurrent density of 500 μA than g-C3N4. These results are supported by the Tafel slopes and PL (photoluminescence spectroscopy) studies by showing the smallest slope and lesser electron-hole recombination for 0.05 ZG. Increased lifetime of 107 ms and a higher donor density of 3.6 × 1019 cm?3 for 0.05 ZG is observed. The smallest semicircle for 0.05 ZG in EIS implies the least charge transfer resistance among the prepared heterojunctions. All the results comply with each other showing the successful formation of type-II heterojunction for enhanced PEC water splitting.  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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The commencement of the industrial revolution paved the way for the fabrication of flexible polymers with high‐strength metalloceramics as novel materials of all kinds. Fabricating metal–ceramic/polymer conductive composites is one such dimension followed for the present research work making use of the properties of the three components. Electroless deposition, for permanent metallic coating, was performed to coat Al2O3 with metallic Cu followed by the inclusion of the Cu–Al2O3 filler into a poly(vinyl chloride) (PVC) matrix. X‐ray diffraction and energy‐dispersive X‐ray studies predicted a prominent growth of metallic Cu crystallites onto Al2O3 with an increased average size and variation in elemental composition, respectively, when compared to pristine Al2O3. Morphological behaviour via scanning electron microscopy also envisioned uniform Cu coating onto Al2O3 and a homogeneous dispersion throughout the polymer matrix. When incorporated into PVC, electrical conductivity analysis highlighted a distinct variation in composite phases from insulating (7.14 × 10?16 S cm?1) to semiconducting behaviour (8.33 × 10?5 S cm?1) as a function of Cu–Al2O3 filler. Mechanical behaviour (tensile strength, Young's modulus and elongation at break) and thermal properties of the prepared composites also indicated a substantial improvement in material strength with Cu–Al2O3 incorporation. The enhanced electrical conductivity along with improved thermomechanical status with significant filler–matrix interaction permits the potential usage of such novel composites in a range of state‐of‐the‐art semiconducting electronic devices. © 2018 Society of Chemical Industry  相似文献   
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Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.There-fore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detec-tivity of 9.8×1012 Jones was obtained under 0.1 mW/cm2 white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 10s at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×1013 Jones with a responsivity of 11.12 A/W was obtained under 0.1 mW/cm2 white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mis-match bandgap between PbS-TBAI/CsPbI3 interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.  相似文献   
30.
Objective: The goal of the present work was to make novel co-polymeric micellar carriers for the delivery of docetaxel (DTX).

Significance: Co-polymeric micelles can not only solubilize DTX and eliminate the need for toxic surfactants to dissolve it, but also cause passive targeting of the drug to the tumor and reduce its toxic side effects.

Methods: Poly(styrene-maleic acid) (SMA) was conjugated to poly (amide-ether-ester-imide)-poly ethylene glycol (PAEEI-PEG). Copolymer synthesis was proven by Fourier transform infrared (FTIR) and 1H-nuclear magnetic resonance (1H-NMR). The SMA-PAEEI-PEG micelles loaded with DTX were prepared and their critical micelle concentration (CMC), zeta potential, particle size, entrapment efficiency, and their release efficiency were studied. MCF-7 and MDA-MB231 breast cancer cells were used to evaluate the cellular uptake and cytotoxicity of the micelles. The antitumor activity of the DTX-loaded nanomicelles was measured in Balb/c mice.

Results: The FTIR and HNMR spectroscopy confirmed successful conjugation of SMA and PAEEI-PEG. The drug loading efficiency was in the range of 34.01–72.75% and drug release lasted for 120?h. The CMC value of the micelles was affected by the SMA/PAEEI-PEG ratio and was in the range of 29.85–14.28?µg/ml. The DTX-loaded micelles showed five times more cytotoxicity than the free drug. The DTX loaded micelles were more effective in tumor growth suppression in vivo and the animals showed an enhanced rate of survival.

Conclusion: The results show that the SMA-PAEEI-PEG micelles of DTX could potentially provide a suitable parenteral formulation with more stability, higher cytotoxicity, and improved antitumor activity.  相似文献   
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