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Chronic stress caused by prolonged emotional pressure can lead to various physiological issues, including reproductive dysfunction. Although reproductive problems can also induce chronic stress, the impact of chronic stress-induced reproductive dysfunction remains contentious. This study investigates the effects of chronic unpredictable stress (CUS) on reproductive neuropeptides, sperm quality, and testicular morphology. Sixteen twelve-week-old Sprague Dawley rats were divided into two groups: a non-stress control group and a CUS-induced group. The CUS regimen involved various stressors over 28 days, with both groups undergoing behavioural assessments through sucrose-preference and forced-swim tests. Hypothalamic gene expression levels of CRH, PNX, GPR173, kisspeptin, GnRH, GnIH , and spexin neuropeptides were measured via qPCR, while plasma cortisol, luteinizing hormone (LH), and testosterone concentrations were quantified using ELISA. Seminal fluid and testis samples were collected for sperm analysis and histopathological evaluation, respectively. Results showed altered behaviours in CUS-induced rats, reflecting stress impacts. Hypothalamic corticotropin-releasing hormone (CRH) expression and plasma cortisol levels were significantly higher in CUS-induced rats compared to controls (p < 0.05). Conversely, phoenixin (PNX) expression decreased in the CUS group (p < 0.05), while kisspeptin, spexin , and gonadotropin-inhibitory hormone (GnIH) levels showed no significant differences between groups. Despite a significant increase in GnRH expression (p < 0.05), plasma LH and testosterone concentrations were significantly lower (p < 0.05) in CUS-induced rats. Histopathological analysis revealed abnormal testis morphology in CUS-induced rats, including disrupted architecture, visible interstitial spaces between seminiferous tubules, and absence of spermatogenesis. In conclusion, CUS affects reproductive function by modulating PNX and GnRH expression, influencing cortisol levels, and subsequently reducing plasma LH and testosterone concentrations. This study highlights the complex interplay between chronic stress and reproductive health, emphasizing the significant impact of stress on reproductive functions. • Chronic stress has recently associated with decreasing of reproductive health quality among males. • Chronic stress significantly reduced reproductive neuropeptides gene expression, phoenixin levels and reproductive hormones. • CUS influences reproductive function by modulating phoenixin and GnRH expression. • Testis and sperm morphology are severely affected by the CUS induced. [ABSTRACT FROM AUTHOR]

Valved allografts and xenografts for reconstruction of the right ventricular outflow tract (RVOT) lack durability and do not grow. We report the first clinical use of a completely bioabsorbable valved conduit (Xeltis pulmonary valve - XPV) in children. Twelve children (six male), median age five (two to twelve) years and median weight 17 (10 to 43) kg, underwent RVOT reconstruction with the XPV. Diagnoses were: pulmonary atresia with ventricular septal defect (VSD) (n = 4), tetralogy of Fallot (n = 4), common arterial trunk (n = 3), and transposition of the great arteries with VSD and pulmonary stenosis (n = 1). All had had previous surgery, including prior RVOT conduit implantation in six. Two diameters of conduit 16mm (n = 5) and 18mm (n = 7) were used. At 24 months none of the patients has required surgical re-intervention, 9 of the 12 are in NYHA functional class I and three patients in NYHA class II. None of the conduits has shown evidence of progressive stenosis, dilation or aneurysm formation. Residual peak gradient of >40 mm Hg was observed in three patients, caused by kinking of the conduit at implantation in 1 and distal stenosis in the peripheral pulmonary arteries in 2 patients. Five patients developed severe pulmonary valve insufficiency (PI); the most common mechanism was prolapse of at least one of the valve leaflets. The XPV conduit is a promising innovation for RVOT reconstruction. Progressive PI requires however an improved design (geometry, thickness) of the valve leaflets. [ABSTRACT FROM AUTHOR]

In this paper, the performance improvement of an electric injera baking stove is studied experimentally using copper powder as additive material for baking plate preparation. The performance of conventional electric injera baking stove is low because of the poor thermal conductivity of the backing plate material. This leads to a high energy consumption ranging from 1.23 to 1.41 kWh for initial heating and observed uneven temperature distribution on the baking surface. Therefore, this study focuses on reducing the time required for initial heating so that the energy consumption will be reduced which will result in overall thermal efficiency improvement. The composite material is developed in four different samples with mixture of different ratios of clay soil and copper powder. Then the performance is studied experimentally. The experiments are conducted for analyzing the initial heating time, plate surface temperature distribution and energy consumption. The results show that the composite material thermal conductivity property has been improved due to addition of copper powder. The sample with 20% copper powder and 80% clay soil ratio mixture has given a better overall performance than other composition (i.e. less initial heating time, better uniform baking surface temperature and less energy consumption/kg of injera). The thermal efficiency of the improved baking stove is 88.55% which is of Grade 1 as per the Ethiopian Standard 'ES 04090 sub article 4.2 while that of the conventional electric baking stove is 53.36%. Hence, the addition of copper powder to clay has resulted in an overall improvement in thermal efficiency. The quality of injera baked is also very nice with bubbly eye in the front and smooth back side. • Thermal efficiency of electric Injera baking stove • Composite material for electric Injera baking plate • Copper powder as additive material for improving Injera baking plate efficiency • Minimize electric heating-up time to reduce consumption and improve efficiency [ABSTRACT FROM AUTHOR]

This study developed and examined a new operational matrix approach utilizing the Vieta-Fibonacci polynomial for the numerical solution of generalized Caputo-type differential equations with fractal-fractional terms. Based on the proposed approach, the fractal-fractional differential equations with generalized Caputo-type derivatives were reduced into a system of algebraic equations, which was further solved to obtain the unknown solution. The convergence and error bounds are theoretically calculated. The results are quantitatively confirmed in various cases. To demonstrate the correctness and computational efficacy of this proposed technique, it is compared to other well-known methods. [ABSTRACT FROM AUTHOR]

The present examination includes manufacture and portrayal of cryogel bio-composite implants containing chitosan-gelatin (CS-GT), cerium–zinc doped hydroxyapatite (CS-GT/Ce-Zn-HA) by cryogelation technique. The prepared cryogel biocomposites (CS-GT/HA and CS-GT/Ce-Zn-HA) were described by scanning electron microscope (SEM) and X-Ray diffraction (XRD) contemplates. The expansion of Ce-Zn in the CS-GT implants essentially expanded growing, diminished swelling, expanded protein sorption, and expanded bactericidal movement. The CS-GT/Ce-Zn-HA biocomposite had non-toxic towards rodent osteoblast cells. So the created CS-GT/Ce-Zn-HA biocomposite has favorable and potential applications over the CS-GT/HA platforms for bone tissue engineering. [ABSTRACT FROM AUTHOR]

The exosome is an emerging concepts biomarkers due to their abnormal expression in various diseases. Research on exosome has already shifted from the laboratory to clinical application. This study uses bioinformatics technology to identify functional changes in proteins of serum exosomes from burn patients. A total of 231 quantifiable differentially-expressed proteins were screened out, 31 of them had statistically significant changes in expression levels. In the test group, expression of2 proteins had downregulated, whereas that of 29 proteins upregulated. Gene Ontology analysis demonstrates that differentially-expressed proteins were primarily identified in extracellular vesicles and platelet α granules, which can alter enzyme inhibitor activities, heparin-binding, coagulation, and lipid transport. Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrates that ITGA2B and ITGB3 proteins, which were significantly upregulated in the burn group, were primarily involved in the PI3K/AKT signaling pathway. Western blotting confirmed that the expressions of ITGA2B and ITGB3 in burn patient tissue samples were higher than those in the control group; conversely, the expression of CD9 was lower than that in the control group. In burn patients, the upregulated proteins ITGA2B and ITGB3 of serum exosomes likely participate in injury detection and repair via PI3K/AKT signaling pathways. [ABSTRACT FROM AUTHOR]

The conventional approaches for treating bone defects such as autografts donor tissue shortages and allografts transmission of diseases pose many shortcomings. The objective of this study was to design a nano strontium/magnesium doped hydroxyapatite (Sr/Mg-HA) with chitosan (CTS) and multi-walled carbon nanotubes (MWCNT) (Sr/Mg-HA/MWCNT/CTS) biocomposite was created to support the growth of osteoblasts using a solvent evaporation method. To help the growth of osteoblasts, a solvent evaporation technique was used to design a nano strontium/magnesium doped hydroxyapatite with chitosan and multi-walled carbon nanotubes biocomposite. We studied the biocompatibility and efficiency in vitro of biocomposite following physicochemical analyzes. Tests of biocompatibility, cell proliferation, mineralization, and osteogenic differentiation have shown that in-vitro safety and effectiveness of biocomposite are good. The performance of biocomposite was more efficient in in-vitro as well as in vivo experiments than in Sr/Mg-HA nanoparticles. Briefly, the Sr/Mg-HA/MWCNT/CTS biocomposite is an ideal candidate for effective bone repair in clinics with excellent mechanical properties with durable multi-biofunctional antibacterial properties and osteoinductivity. [ABSTRACT FROM AUTHOR]

Ductal stenting is performed to retrain involuted left ventricles (LVs) in patients with d -transposition of the great arteries and intact ventricular septum (TGA-IVS). However, its efficacy is largely unknown. This study aimed to determine the safety and efficacy of ductal stenting in retraining of the involuted LV in patients with TGA-IVS. This was a single-center, retrospective study. Echocardiographic assessment of the LV geometry, mass, and free wall thickness was performed before stenting and before the arterial switch operation. Patients then underwent the arterial switch operation, and the postoperative outcomes were reviewed. There were 11 consecutive patients (male, 81.8%; mean age at stenting, 43.11 ± 18.19 days) with TGA-IVS with involuted LV who underwent LV retraining by ductal stenting from July 2013 to December 2017. Retraining by ductus stenting failed in 4 patients (36.3%). Two patients required pulmonary artery banding, and another 2 had an LV mass index of less than 35 g/m2. Patients in the successful group had improved LV mass index from 45.14 ± 17.91 to 81.86 ± 33.11g/m2 (p = 0.023) compared with 34.50 ± 10.47 to 20.50 ± 9.88 g/m2 (p = 0.169) and improved LV geometry after ductal stenting. The failed group was associated with an increased need for extracorporeal support (14.5% vs 50%, p = 0.012). An atrial septal defect–to–interatrial septum length ratio of more than 0.38 was associated with failed LV retraining. Ductal stenting is an effective method to retrain the involuted LV in TGA-IVS. A large atrial septal defect (atrial septal defect–to–interatrial septum length ratio >0.38) was associated with poor response to LV retraining. [ABSTRACT FROM AUTHOR]

Background: Fisetin, a polyphenolic compound, has drawn notable attention owing to its antioxidant, anti-inflammatory, anti-cancer and neuroprotective effects. However, the cardiac effects of fisetin are not clear yet.Hypothesis: The aim of the present study is to examine the cardioprotective effect of fisetin against Ang-II induced apoptosis in H9c2 cells and in spontaneous hypertensive rats (SHR).Methods/study Design: The in vitro protective effect of fisetin was evaluated after the cells were treated with fisetin (50 µM/ml/ 24  h) for 2  h prior or after Ang-II administration to induce apoptosis. For in vivo experiments, SHRs were orally administered with fisetin (10  mg/kg) twice a week for 6 weeks. Cellular apoptosis was analyzed by TUNEL staining assay and the modulation in the expression levels of proteins involved in apoptosis and cell survival were determined by western blotting.Results: Our results demonstrate the potent cardioprotective efficacy of fisetin against Ang-II induced apoptosis in H9c2 cells and in SHR models. Fisetin administration reduced the apoptotic nuclei considerably And reduced the expression of apoptotic proteins such as TNF- α, Fas L, FADD, Cleaved caspase-3 and Cleaved PARP and increased the cell survival and anti-apoptotic proteins like Bcl-2, Bcl-xL, p-IGF1R, p-PI3K and p-AKT in both in vitro and in vivo models.Conclusion: In conclusion, the results of the present study reveal that fisetin activates the IGF-IR-dependent p-PI3K/p-Akt survival signaling pathway and suppresses the caspase dependent apoptosis. [ABSTRACT FROM AUTHOR]

Highlights • Novel nanocrystalline zeolite X (nZX) was synthesized from Indian coal flyash (CFA). • CFA and nZX were characterized and compared with commercial 13X zeolite (CZX). • Surface area and average crystal size of nZX are 651.34 m2/g and of 16.28 nm. • Central composite design was used for optimization of crystal violet (CV) adsorption. • Adsorption capacity and % dye removal onto nZX are 234.57 mg/g and 99.52%. Abstract A novel nanocrystalline zeolite X (nZX) was synthesized using coal fly ash of eastern India for adsorptive removal of a textile dye—crystal violet (CV) from aqueous solution. nZX was characterized by TEM, XRF, FESEM, XRD, FTIR, and BET. The nZX has a surface area, an average crystal size, an average particle size, crystallinity, and product yield of 651.34 m2/g, 16.28 nm, 27.28 nm, 82% and 91% respectively. A maximum of 99.52% CV was removed at optimized condition of pH 9, 60 min contact time, 50 °C temperature, 100 mg/L initial dye concentration and 1.0 g/L adsorbent mass. A high correlation coefficient (R 2 = 0.998) good agreement between the predicted and experimental values. The maximum Langmuir adsorption capacity of 234.57 mg/g was obtained. The adsorption of CV followed a pseudo-second order kinetic model. The synthesized nZX was also found to be very efficient up to five regenerative cycle in removing the dye. Therefore, the synthesized nZX could be utilized for efficient removal of CV dye in real wastewater. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Conjoined twins are rare congenital malformations known to be associated with cardiac abnormalities. Management of transposition of the great arteries with an intact ventricular septum in this subgroup of patients is challenging, especially in the presence of multiple comorbidities. Prevention of left ventricular involution until the patient is stable for an arterial switch operation is a real challenge. We report a case of early ductal stenting to keep the left ventricle well trained in a separated conjoined twin who eventually underwent an arterial switch operation. [ABSTRACT FROM AUTHOR]

The mobility and toxicity of Arsenite (As (III)) hinder its removal from aquatic environments, posing a serious threat to human health. Nanoparticles based on a stable CoFe-based metal-organic framework (MOF) were produced and investigated for their potential application as an adsorbent in the process of removing arsenate from an aqueous environment, which is a major health concern. The synthesized materials were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Particle size analyzer, and electron microscopy techniques. Inductively coupled plasma mass spectrometry (ICP-MS) was used in order to carry out a comprehensive investigation of the As (III) elimination process. The synergistic effect between Co and Fe in the MOF enhances the arsenic removal efficiency to nearly 99% and enables a larger adsorption capacity. In addition, The adsorption efficiency was further investigated with respect to various parameters, including initial solution pH, adsorbent loading, co-existing ions, and contact time. This new Co x Fe 3−x O 4 adsorbent has an impressive adsorption capability of 119.1 mg/g at neutral pH. The Co x Fe 3−x O 4 adsorbent shows an efficient As(III) adsorption capacity compared with other adsorbents. The adsorption mechanism was found to involve metal-oxygen bonding, hydroxyl groups, and electrostatic interactions. Due to its superior adsorption capability, the Co x Fe 3−x O 4 catalyst has the potential to be a useful material for the removal of arsenic from water. [Display omitted] • Co x Fe 3-x O 4 was synthesized by solvothermal combined calcination for As(III) removal. • Synthesized material characterized using various analytical techniques. • Synergistic effect between Co and Fe enhances adsorption efficiency. • Co x Fe 3-x O 4 shows impressive adsorption capability of 119.1 mg/g. • Adsorption mechanism involves metal-oxygen bonding, hydroxyl groups, and electrostatic interactions. [ABSTRACT FROM AUTHOR]

Aortic dissection occurs following a tear in the tunica intima of the aortic wall resulting in blood entering between the intima and media. Type A aortic dissection can rarely manifest as upper limb malperfusion. This is regarding a patient who presented with intermittent malperfusion of the bilateral upper limbs and was initially managed as acute limb ischemia. An attempt of embolectomy didn't yield any clots. Urgent imaging with computed tomography angiogram of bilateral upper limbs revealed type A aortic dissection (TAAD). TAAD is a surgical emergency which can rarely manifest as intermittent malperfusion of upper limbs. This could be explained by the dissection flap's dynamic obstruction of the right brachiocephalic trunk and left subclavian artery. In patients with a discrepancy in pulse between both limbs or intermittent ischemia of limbs, aortic dissection should be considered a differential diagnosis. • Type A Aortic dissection can manifest as bilateral upper limb ischemia. • CT angiogram is considered in those with intermittent upper limb ischemia. • Dynamic and static obstruction of vessels by the dissection flap would explain this. • Embolectomy in such atypical presentations would delay the diagnosis. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants are among the main hotspots for the release of antibiotic resistance genes (ARGs) into the environment. ARGs in treated wastewater can be found in the intracellular DNA (iDNA) and in the extracellular DNA (eDNA). In this study, we investigated the fate and the distribution (either in eDNA or in iDNA) of ARGs in the treated wastewaters pre and post-disinfection by shotgun metagenomics. The richness of the intracellular resistome was found to be higher than the extracellular one. However, the latter included different high risk ARGs. About 11% of the recovered metagenome assembled genomes (MAGs) from the extracted DNA was positive for at least one ARG and, among them, several were positive for more ARGs. The high-risk ARG bac A was the most frequently detected gene among the MAGs. The disinfection demonstrated to be an important driver of the composition of the antibiotic resistomes. Our results demonstrated that eDNA represents an important fraction of the overall ARGs, including a number of high-risk ARGs, which reach the environment with treated wastewater effluents. The studied disinfections only marginally affect the whole antibiotic resistome but cause important shifts from intracellular to extracellular DNA, potentially threating human health. [Display omitted] • Disinfection influences the composition of the antibiotic resistome. • Extracellular DNA is a carrier of high risk antibiotic resistance genes. • bac A is the most frequent antibiotic resistance gene detected in MAGs. [ABSTRACT FROM AUTHOR]

Since 4-nitrophenol (4-NP) is a high-priority hazardous contaminant that can harm humans, animals, and plants, detecting and determining its presence in the environment is an issue of utmost importance. This study was focused on the electrochemical detection of 4-NP using a cerium-iron phosphate electrode modified on a glassy carbon electrode (CeFeP/GC). X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction, and X-ray photoelectron spectroscopy confirmed the formation of CeFeP. TEM analysis reveals that CeFeP formation is a flower-like morphology comprising several uniform rods. As synthesized, flower-like CeFeP catalyst was used for excellent bifunctional electrochemical detection and reduction of toxic 4-NP. Cyclic voltammetry and differential pulse voltammetry (DPV) were performed to analyze the stepwise electrode-modification process. The CeFeP/GC electrode displayed a higher cathodic current response at a low potential of − 0.44 V for 4-NP detection. At optimized conditions, CeFeP/GC electrode showed a wide range sensitivity of 0.1–50 μM with a limit of detection (LOD) of 0.01 μM. Additionally, the CeFeP catalyst was employed for the catalytic degradation of 4-NP and exhibited excellent catalytic activity towards 4NP- reduction. The proposed catalyst completes the reduction reaction within 11 min. The proposed bifunctional electrocatalyst is a very useful, inexpensive, and novel sensor platform with considerable potential for environmental applications [Display omitted] • CeFeP was synthesized and used as an electrode material. • The morphology results proved the flower-like structure comprising several uniform rods. • Modified electrodes were used for electrochemical sensing of 4-nitrophenol. • CeFeP acts both as an electron mediator and a reaction catalyst. • CeFeP catalyst had superior catalytic activity compared to those of the others. [ABSTRACT FROM AUTHOR]

Earlier reports indicate that ethanol/bioethanol can replace conventional diesel fuel by 15%, when it is emulsified with diesel and used as an alternative fuel in a compression ignition (CI) engine. In this study, initially BMDE15, a bioethanol emulsion containing 15% bioethanol, 84% diesel and 1% surfactant was characterised for its fuel properties and compared with those of diesel fuel properties. The numerical value indicates the percentage of bioethanol in the BMDE15 emulsion. For the investigation, bioethanol was obtained from the Mahua Indica flower which was collected from the Madhuca Indica tree, and it was produced from fermentation process using Saccharomyces cerevisiae . Further, the BMDE15 emulsion was tested in a single cylinder, four stroke, air cooled, DI diesel engine developing a power of 4.4 kW at a rated speed of 1500 rpm. Two important combustion parameters: cylinder pressure and ignition delay, and two important emission parameters: nitric oxide (NO) and smoke emissions were determined and compared with those of diesel operation at all loads. The experimental results were validated using mathematical modelling, and the analysis of the results is presented in this paper. [ABSTRACT FROM AUTHOR]

Background This study compares the midterm results of mitral valve repair using the biodegradable ring versus repair with non-ring annuloplasty techniques for congenital mitral valve disease in young children where it was not possible to use standard commercial rings. Methods Between February 2006 and November 2011, 68 patients underwent mitral valve repair for congenital mitral valve disease. Thirty-nine (57%) patients underwent concomitant annuloplasty using the biodegradable ring (group A) and 29 (43%) patients using non-ring annuloplasty techniques (group B). The median age of repair was 2 years (range 1 month to 14 years). Results There were no hospital deaths or major postoperative morbidity. At a median follow-up of 3.8 years (range, 2 months to 5.1 years), overall survival at 5 years was 97% ± 3% for group A and 88% ± 8% for group B ( p = 0.29). Freedom from valve failure was 90% ± 7% in group A and 74% ± 9% in group B ( p = 0.026). The freedom from reoperation was 100% in group A and 84% ± 9% in group B ( p = 0.04). The mean transmitral gradients were 4.3 ± 1.8 mm Hg in group A and 4.2 ±1.7 mm Hg in group B ( p = 0.77). Conclusions Mitral valve repair using the biodegradable ring for congenital mitral valve disease was superior compared with non-ring annuloplasty repair. Excellent survival benefit, freedom from reoperation, and valve failure without significant elevation of transmitral gradients, suggests its important role in young children with smaller annular sizes where standard commercial rings are not available or recommended. [ABSTRACT FROM AUTHOR]

Porphyrins coated ZnO is an interesting material where the exposure to light and gas may cooperate to modulate the respective sensitivities. In this work, the gas sensing properties of porphyrins functionalized laterally grown ZnO nanorods are introduced. The porphyrin layer incompletely coats the semiconductor surface in order to keep both ZnO and porphyrins in contact with analyte. It is known that UV light may prompt the chemical sensitivity of ZnO replacing the high temperature condition. Here we demonstrate that because of the photo-injection of electrons from porphyrin to the ZnO, the same impact could be acquired with visible light. [ABSTRACT FROM AUTHOR]

Photoconductivity and gas sensitivity cooperate in porphyrins coated ZnO nanostructures. However, in organic coated semiconductors the former is regulated by a number of mechanisms, involving the charge transfer in the organic layer. Since organic layers are poor conductors these processes are quite slow and the sensor may exhibits a long time drift before to be operative as gas sensor. In this paper we show that under light modulation, the carrier frequency component of the signal is free of drift and it can readily indicate the interaction with volatile compounds. [ABSTRACT FROM AUTHOR]

Hypoxia-inducible factor-1α (HIF-1α) is important for placental development. This study aims to determine whether the increased level and expression of HIF could be used to demonstrate failed placentation in women with preeclampsia. The study included 20 pregnant females [10 with and 10 without preeclampsia (the control group)]. Placental tissues were collected and stained with hematoxylin and eosin. Immunohistochemical studies for evaluating the expression of HIF-1α by these tissues were then performed. The results demonstrated that placental tissues collected from mothers with preeclampsia showed a variety of histomorphological changes. All the cytotrophoblasts rimming the placental villi in mothers with preeclampsia demonstrated a strong and uniform nuclear staining with HIF-1α. The study results indicated that cytotrophoblasts respond to an ischemic environment by their nuclear expression of HIF-1α, and thus we conclude that this transcription factor has a significant potential as a marker for preeclampsia. [ABSTRACT FROM AUTHOR]

In this work, an efficient reduced graphene-oxide/zinc-oxide (rGO/ZnO) nano-photocatalyst was synthesized via an eco-friendly hydrothermal method to degrade organic dye under visible light exposure and analyzed with Scanning Kelvin Probe (SKP). Prepared samples were characterized via X-ray diffraction (XRD), Field emission-scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform-infrared spectroscopy (FTIR), and UV-Visible absorption spectrophotometer. Structural, morphological, and topological studies revealed the crystal growth of ZnO nanoparticles on rGO as evidenced from XRD, FESEM, and TEM images. UV-Vis studies show the decrease in bandgap energy of rGO/ZnO after the heterostructure formation. UV results confirm the enhanced photodegradation of RhB aqueous solution under visible light. The work function (ɸ) of rGO, ZnO, rGO/ZnO is determined in dark and light conditions by using Scanning Kelvin probe microscopy and discussing their contribution to the photocatalytic process. The novelty of this work is the SKP technique which was used to analyze the degradation mechanism of RhB in the presence of rGO/ZnO catalyst. It is a new way to find out the carrier transport mechanism at the surface of materials with the recorded work function mapping. Photocatalytic activity of rGO/ZnO has shown the maximum degradation of 97% for RhB (pH 7). Our results indicate that more electrons have moved at the catalyst surface and reacted with organic impurities due to larger surface area, which is responsible for suppressing the recombination of photo-induced carriers. [Display omitted] • Facile synthesis and photocatalytic activities of nanostructured rGO/ZnO photocatalyst were investigated. • Exfoliated few-layer rGO nanosheets were obtained with the help of a probe sonicator. • The bandgap of rGO/ZnO nanocomposite was decreased after coupling of rGO nanosheets. • Surface electronic properties and work function were determined by scanning Kelvin probe (SKP) spectroscopy. • rGO/ZnO nanocomposite has shown an enhanced photocatalytic activity with degradation efficiency (97%) for Rhodamine B dye. [ABSTRACT FROM AUTHOR]

Abstract: Power efficiency will be one of the primary factors dictating the choice of future network deployments. Passive Optical Networks (PONs) in general consume less power and are well positioned to be the technology of choice for future access networks. In a PON, the Optical Network Units (ONUs), that provide the interface between the end user and the Optical Line Terminal (OLT), consume a substantial amount of power. Typically, 2MB or more buffer capacity is used in an ONU for holding upstream packets. This consumes around 1.29W of leakage power when idle. In the current work, we show the relationship between buffer capacity and leakage power consumption. This motivated us to propose buffer reduction as a strategy to reduce power consumption of an ONU. We propose three schemes viz. Zero Buffers (ZBs), Node Proportional Buffers (NBs) and Rate Proportional Buffers (RBs). They impose aggressive buffer capacity restrictions on the ONU to reduce power consumption. Having said that, these schemes cannot be realized without modifications to the basic network operation. We propose mechanisms required to support the buffer reduction schemes. Through simulations we explore the relationship between power consumption and network performance. We also present the comparison of the proposed schemes in terms of network performance with different network loads. Simulation results indicate that despite buffer size reduction, an acceptable level of application level performance can be achieved. We show that buffer reduction as a strategy is viable and can cut down more than 90% of leakage power consumed by packet buffers at the ONU. [Copyright &y& Elsevier]

Abstract: Long Reach PONs (LR-PON) were proposed to extend the benefits of Passive Optical Networks (PON) to more users and to a larger area. This paper considers a Dynamic Bandwidth Allocation (DBA) based on a hybrid combination of Time Division Multiplexing (TDM) and Wavelength Division Multiplexing (WDM). The time complexity of the DBA algorithm is typically O(n log n), where n denotes the number of ONUs. Since the maximum number of supported ONUs in an LR-PON can be as high as 2048, the computation time required for computing a schedule will be very high and directly impacts the overall network performance. In this paper, we have presented a grouping strategy to reduce the computation requirements. The number of ONUs is split into mutually exclusive groups with the OLT scheduling each group independently and in parallel. With the static grouping strategy every user is assigned to a group and the assignment of wavelength resources is fixed. However, with non-uniform loads, we observed that static grouping was not found to be suitable as the delay variation was significant across the groups. To address this gap, we introduce the concept of dynamic grouping and define three dynamic grouping heuristics that adapt to the current network load conditions and (re)allocate the ONUs and wavelength resources suitably. The proposed schemes have been compared in terms of delay variation and wavelength utilization. Of the three heuristics, ONU to Least Loaded wavelength group (OLL) and Least Wavelength Resources (LWR) heuristics balance the packet delay across ONUs assigned to different groups and Proportional Wavelength Usage (PWU) heuristic reduces power consumption by allocating fewer wavelength resources. [Copyright &y& Elsevier]

Abstract: In this paper we study the sensitivity to volatile organic vapors of the surface potential of metalloporphyrins coated ZnO nanorods. The hybrid material has been growth with an original method based on the direct addition of metalloporphyrins to the hydrothermal precursor solution. The resulting film shows a complete coating of the ZnO surface expected to improve the photovoltaic characteristics. The chemical sensitivity of the surface potential has been measured in dark and in white light illumination. For sake of comparison, the hybrid material has been compared with those obtained from a casting coated porphyrin functionalized ZnO nanorods. Results show that the material preparation strongly influences the sensor properties, and in case of the hybrid material the illumination with visible light elicits an increase of the sensor response that is proportional to the ability of the volatile compound to donate electrons. [Copyright &y& Elsevier]

Abstract: In this work, gas sensing properties of monocarboxy tetraphenylporphyrin functionalized ZnO nanorods under different light illumination, were investigated. These studies showed that the sensitivity to triethylamine of porphyrin functionalized ZnO nanorod device are greatly enhanced under illumination with visible light. This photoactivated nanostructure composition has the potential for gas sensor device applications. [Copyright &y& Elsevier]

Abstract: Calcium looping (CaL) is a promising post-combustion CO2 capture technology which is carried out in a dual fluidized bed (DFB) system with continuous looping of CaO, the CO2 carrier, between two beds. The system consists of a carbonator, where flue gas CO2 is adsorbed by CaO and a regenerator, where captured CO2 is released. The CO2-rich regenerator flue gas can be sequestered after gas processing and compression. A parametric study was conducted on the 10kWth DFB facility at the University of Stuttgart, which consists of a bubbling fluidized bed carbonator and a riser regenerator. The effect of the following parameters on CO2 capture efficiency was investigated: carbonator space time, carbonator temperature and calcium looping ratio. The active space time in the carbonator, which is a function of the space time and the calcium looping ratio, was found to strongly correlate with the CO2 capture efficiency. BET and BJH techniques provided surface area and pore volume distribution data, respectively, for collected sorbent samples. The rate of sorbent attrition was found to be 2wt.%/h which is below the expected sorbent make-up rate required to maintain sufficient sorbent activity. Steady-state CO2 capture efficiencies greater than 90% were achieved for different combinations of operational parameters. Moreover, the experimental results obtained were briefly compared with results derived from reactor modeling studies. Finally, the implications of the experimental results with respect to commercialization of the CaL process have been assessed. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the cryptographic key exchange problem in a wireless network. An infrastructure-based wireless network such as a Wireless LAN is considered. An indoor wireless locationing system, based on a collection of beacon nodes, is assumed to be present. The proposed technique makes use of ranging information between nodes to establish a shared secret key between security principals. The key exchange technique is based on the notion of symmetric ranging combined with Merkle’s puzzles. This technique is independent of any underlying encryption algorithm. The system’s security properties, in terms of the time to obtain the secret key and the time for an adversary to break the key, are analyzed using empirical implementations. The results show that the secret key can be established in five seconds between the principals, while it requires the adversary two orders of magnitude more time in some cases to substantially more than an hour (when the implementation times out) in most cases. [Copyright &y& Elsevier]

Abstract: In this paper, we investigate the problem of enhancing dual-failure restorability in path protected mesh-restorable optical Wavelength Division Multiplexed (WDM) networks. Recent studies have demonstrated the need to survive simultaneous dual-link failures and have also provided solutions for handling such failures. A key finding of these early efforts is that designs providing complete (i.e. 100%) protection from all dual-failures need almost triple the spare capacity compared to a system that protects against all single-link failures. However, it has also been shown that systems designed for 100% single-link failure protection can provide reasonable protection from dual-link failures [M. Clouqueur, W. Grover, Mesh-restorable networks with 74 enhanced dual-failure restorability properties, in: Proc. SPIE OPTICOMM, Boston, MA, 2002, pp. 1–12]. Thus, the motivation for this work is to develop a hybrid mechanism that provides maximum (close to 100%) dual-failure restorability with minimum additional spare capacity. The system architecture considered is circuit-switched with dynamic arrival of sessions requests. We propose an adaptive mechanism, which we term active protection, that builds upon a proactive path protection model (that provides complete single-failure restorability), and adds dynamic segment-based restoration to combat dual-link failures. The objective is to optimize network survivability to dual-link failures while minimizing additional spare capacity needs. We also propose a heuristic constraint-based routing algorithm, which we term best-fit, that aids backup multiplexing among additional spare paths towards this goal. Our findings indicate that the proposed active protection scheme achieves close to complete (100%) dual-failure restorability with only a maximum of 3% wavelength-links needing two backups, even at high loads. Moreover, at moderate to high loads, our scheme attains close to 16% improvement over the base model that provides complete single-failure restorability. Also, the best-fit routing algorithm is found to significantly assist backup multiplexing, with around 15%–20% improvement over first-fit at all loads. The segment-based restoration algorithm reiterates the importance of utilizing wavelength converters in protection and is seen to provide around 15%–20% improvement over link restoration especially at moderate to high loads. [Copyright &y& Elsevier]

The hydrothermal preparation of o -dianisidine and triazine interlinked porous organic polymer and its successive derivatisation via metal infusion (Ni, Cu) under hydrothermal and calcination conditions (700 °C) to yield pristine (ANIPOP-700) and Ni/Cu decorated porous carbon are described here (Ni-ANIPOP-700 and Cu-ANIPOP-700). To confirm their chemical and morphological properties, the as-prepared materials were methodically analyzed using solid state 13C and 15N NMR, X-ray diffraction, Raman spectroscopy, field emission scanning and high resolution transmission electron microscopic techniques, and x-ray photoelectron spectroscopy. Furthermore, the electrocatalytic activities of these electrocatalysts were thoroughly investigated under standard oxygen evolution (OER) and hydrogen evolution reaction (HER) conditions. The results show that all of the materials demonstrated significant activity in water splitting as well as displayed excellent stability (22 h) in both acidic (HER) and basic conditions (OER). Among the electrocatalysts reported in this study, Ni-ANIPOP-700 exhibited a lower overpotential η 10 of 300 mV in basic medium (OER) and 150 mV in acidic medium (HER), as well as a lower Tafel slope of 69 mV/dec (OER) and 181 mV/dec (HER), indicating 30% lower energy requirement for overall water splitting. Gas chromatography was used to examine the electrolyzed products. [Display omitted] • Cu, Ni incorporated POP based on o -anisidine-triazine linkages were prepared. • Ni-ANIPOP-700 exhibited better OER activity under both acidic and basic conditions. • Ni-ANIPOP-700 showed overpotential η 10 of 300 mV for OER and 150 mV for HER. • Ni-ANIPOP700 produced 0.0044 mol H 2 at cathodic half-cell. • Ni-ANIPOP-700 catalyst exhibited excellent catalytic activity and stability (22 h). [ABSTRACT FROM AUTHOR]

Combined hamartoma of the retina and retinal pigment epithelium (RPE) is a benign tumor seen mostly in children. Enhanced-depth imaging optical coherence tomography (OCT) of these tumors often shows an epiretinal membrane, tangential traction, disorganization of the retinal layers, and underlying uniform choroidal thinning. We describe the evolution over 9 years of focal choroidal excavation, a novel finding on OCT characterized as a “microstaphyloma,” in a girl with combined hamartoma of the retina and RPE. [ABSTRACT FROM AUTHOR]

[Display omitted] Discovering of advanced electrocatalyst for water splitting is importance of the improvement of metal air batteries, water electrolyzers. The approach have been developed to fabricate a novel electrocatalyst with more active sites, high surface area and high porous structure for improve the electrocatalytic activity. Metal organic frameworks have been emerging catalyst of higher crystalline, large surface area, has delivering greater potential for efficient OER electrocatalytic activity. Bimetallic metal organic framework (MOFs) is an excellent catalyst for energy storage and energy conversion system. In this work, we report the synthesis of bimetallic MOF by single step solvothermal method using Ni, Cu as metal sources and BDC as a linker. FE-SEM images indicated NiCu-MOF a narrow crystal formation. The electrocatalyst study of the synthesized catalyst was systematically investigated by linear sweep voltammetery, electrochemical impedance spectroscopy and Chronoamprometry under OER condition. The result demonstrated that NiCu-MOF exhibited better catalytic activity towards OER at onset potential and overpotential of 1.48 V and 250 mV with lower tafel slope of 169 mV/dec, indicating that 25% lower energy required for OER. Hence the proposed NiCu-MOF catalyst is an efficient catalyst for sustainable oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Postoperative pulmonary dysfunction prolonging intensive care treatment after cardiac surgery most commonly occurs in patients with a background of pre-existing pulmonary dysfunction. However, many patients have occult dysfunction and present primarily after surgery. We describe and discuss the results of a respiratory optimization program utilizing a peak expiratory flow rate below 400 L/min as a screening test to identify patients in a nurse-directed preoperative clinic. [Copyright &y& Elsevier]

Purpose: To assess the influence of topical ozone administration on patient comfort after third molar surgery.Materials and Methods: A single-blinded randomized controlled clinical trial was designed involving patients who required removal of bilateral impacted mandibular third molars. The predictor variable was the postoperative medication used after third molar surgery. Using the split-mouth design, the study group received topical ozone without postoperative systemic antibiotics, whereas the control group did not receive ozone but only systemic antibiotics. The 2 groups were prescribed analgesics for 2 days. The assessing surgeon was blinded to treatment assignment. The primary outcome variables were postoperative mouth opening, pain, and swelling. The secondary outcome variable was the number of analgesic doses required by each group on postoperative days 3 to 5. Data analysis involved descriptive statistics, paired t tests, and 2-way analysis of variance with repeated measures (P < .05). SPSS 20.0 was used for data analysis.Results: The study sample included 33 patients (n = 33 in each group). The study group showed statistically relevant decreases in postoperative pain, swelling, and trismus. Further, the number of analgesics required was smaller than in the control group. No adverse effects of ozone gel were observed in any patient.Conclusion: Ozone gel was found to be an effective topical agent that considerably improves patient comfort postoperatively and can be considered a substitute of postoperative systemic antibiotics. [ABSTRACT FROM AUTHOR]