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With the medical internet of things, many automated diagnostic models related to eye diseases are easier. The doctors could quickly contrast and compare retina fundus images. The retina image contains a lot of information in the image. The task of detecting diabetic macular edema from retinal images in the healthcare system is difficult because the details in these images are very small. This paper proposed the new model based on the medical internet of things for predicting diabetic macular edema in retina fundus images. The method called DMER (Diabetic Macular Edema in Retina fundus images) to detect diabetic macular edema in retina fundus images based on improving deep residual network being combined with feature pyramid network in the context of the medical internet of things. The DMER method includes the following stages: (i) ResNet101 improved combining with feature pyramid network is used to extract features of the image and obtain the map of these features; (ii) a region proposal network to look for potential anomalies; and (iii) the predicted bounding boxes against the true bounding box by the regression method to certify the capability of macular edema. The MESSIDOR and DIARETDB1 datasets are used for testing with evaluation criteria such as sensitivity, specificity, and accuracy. The accuracy of the DMER method is about 98.08% with MESSIDOR dataset and 98.92% with DIARETDB1 dataset. The results of the method DMER are better than those of the other methods up to the present time with the above datasets. [ABSTRACT FROM AUTHOR]

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disorder (PID) due to genetic defects in the NADPH oxidase of phagocytes. Affected patients become susceptible to infections such as pneumonia, diarrhea, and skin ulcer types. The patients require life-long treatment with prophylactic antibiotics, antifungals, or hematopoietic stem cell transplantation (HSCT) therapy. Early, accurate diagnosis will contribute to the life-prolonging of patients with CGD. This study's aim is to identify the mutation related to the disease. Case presentation. Six patients from different Vietnamese families were collected for genetic analysis at Allergy, Immunology, and Rheumatology Department, Vietnam National Hospital Pediatrics. They were diagnosed with CGD by flow cytometry test with the conversion of dihydrorhodamine (DHR) 123 to rhodamine 123. We performed whole exome sequencing (WES) as a tool for detecting novel mutations. The mutations were confirmed by the Sanger sequencing method in patients and their families. The influence of the mutations was predicted with the in silico analysis tools: PROVEAN, SIFT, PolyPhen 2, Mutation Taster, and MaxEntScan. In this study, five mutations were found in six unrelated patients with CGD from different Vietnamese families. Three novel pathogenic mutations were detected including one mutation (c.45+2 T>G) in the CYBB gene and two mutations (c.187_188insA and c.289G>C) in the NCF2 gene. Our results of CGD-related mutations contribute to the general understanding of the etiology of the disease and emphasize that WES sequencing can be used as a tool to help to diagnose carriers as well as assist in genetic counseling and prenatal screening. [ABSTRACT FROM AUTHOR]

The central retinal artery and its branches supply blood to the inner retina. Vascular manifestations in the retina indirectly reflect the vascular changes and damage in organs such as the heart, kidneys, and brain because of the similar vascular structure of these organs. The diabetic retinopathy and risk of stroke are caused by increased venular caliber. The degrees of these diseases depend on the changes of arterioles and venules. The ratio between the calibers of arterioles and venules (AVR) is various. AVR is considered as the useful diagnostic indicator of different associated health problems. However, the task is not easy because of the lack of information of the features being used to classify the retinal vessels as arterioles and venules. This paper proposed a method to classify the retinal vessels into the arterioles and venules based on improving U-Net architecture and graph cuts. The accuracy of the proposed method is about 97.6%. The results of the proposed method are better than the other methods in RITE dataset and AVRDB dataset. [ABSTRACT FROM AUTHOR]

In all existed researches on flocking control for multi-agent systems, each agent is modelled as a single point or covered by an circle, ellipse or rectangle; however, in case of limited space traffic systems, many complex vehicles cannot be fitted in these agent shapes. This paper proposes a distributed control law for two-dimensional multiple agents considered as arbitrarily polygonal shapes under limited communication ranges. The proposed control laws guarantee all flocking properties: each agent stays close to its nearby neighbours, no collision occurs in group of agents and velocity of each agent converges to a common vector. The designed control law based on a new anti-collision condition and potential function approach aims at dealing with the issue of collisions between agents. Further, the control signals are bounded and differentiable despite of agent's limited communication ranges and non-smooth boundary in agent shapes. Numerical simulations are implemented to demonstrate the performance of proposed control law for multiple agents with the same and different shapes. [ABSTRACT FROM AUTHOR]

In traditional text based medical image retrieval system, it is hard to find visually similar images in large medical image database. Content-based image retrieval is developed to retrieve similar images and it is based on visual attributes describing the content of an image. Developing a method for content based medical image retrieval is a challenging task. This paper proposed a new method for content-based medical image retrieval based on salient regions and deep learning. The proposed method includes two stages: an offline task to extract local object features and an online task for content-based image retrieval in database. In first stage, we extract local object features of medical image depending on shape, texture and intensity, and features extracted by deep learning applied in saliency of decomposition. Secondly, we make online task for content-based image retrieval in database. The user gives query image as an input and the system will retrieve n top most similar images by similarity comparison with bag of code words feature values obtained in the first stage. Evaluation of the proposed method is based on Precision and Recall values. Our dataset includes 5 groups of medical images with their quality varying from low to high. With the best medical image quality group, the accuray can be 91.61% for Precision and 89.61% for Recall. Comparing the average values with others methods, the results of the proposed method are more than 2 to 5% better. [ABSTRACT FROM AUTHOR]

Background. Left ventricular systolic dysfunction (LVSD) is common in sepsis. Speckle-tracking echocardiography (STE) is a useful emerging tool for evaluating the intrinsic left ventricular systolic function. High-sensitivity cardiac troponin T (hs-cTnT) is the most sensitive biomarker of myocardial injury. However, there are limited data regarding the association between hs-cTnT level and left ventricular systolic dysfunction based on STE in septic patients. We performed this prospective study to evaluate the diagnostic value of hs-cTnT level for subclinical left ventricular systolic dysfunction measured by STE in septic patients according to the sepsis-3 definition. Methods. Patients with sepsis based on sepsis-3 definition admitted to the intensive care unit were prospectively performed STE and hs-cTnT level within 24 hours after the onset of sepsis. Baseline clinical and echocardiographic variables were collected. Left ventricular systolic dysfunction was defined as a global longitudinal strain of ≥−15%. Results. During a 19-month period, 116 patients were enrolled in the study. The elevated hs-cTnT level was seen in 86.2% of septic patients, and 43.1% of patients had LVSD on STE. The median hs-cTnT level and the proportion of elevated hs-cTnT level (>14 ng/L) were significantly higher in patients with LVSD than in patients without LVSD. The area under the ROC curves of hs-cTnT to detect LVSD was 0.73 (P < 0.001). In the multivariate analysis, hs-cTnT (HR, 1.002; 95% CI, 1.000 to 1.004; P = 0.025) and septic shock (HR, 7.6; 95% CI, 2.25 to 25.76; P = 0.001) were independent predictors of LVSD. Conclusion. Our study indicated that the serum hs-cTnT level might be a useful biomarker for detecting LVSD in septic patients. [ABSTRACT FROM AUTHOR]

Background. Left ventricular (LV) systolic dysfunction is common in septic shock. Global longitudinal strain (GLS) measured by speckle tracking echocardiography (STE) is a useful marker of intrinsic left ventricular systolic function. However, the association between left ventricular GLS and outcome in septic patients is not well understood. We performed this prospective study to investigate the prognostic value of LV systolic function utilizing speckle tracking echocardiography in patients with septic shock. Methods. All the patients with septic shock based on sepsis-3 definition admitted to the intensive care unit were prospectively studied with STE within 24 hours after the onset of septic shock. Baseline clinical and echocardiographic variables were collected. The primary outcome was in-hospital mortality. Results. During a 19-month period, 90 consecutive patients were enrolled in the study. The in-hospital mortality rate was 43.3%. Compared with survivors, nonsurvivors exhibited significantly less negative GLS (− 13.1 ± 3.3 % versus − 15.8 ± 2.9 % ; p < 0.001), which reflected worse LV systolic function. The area under the ROC curves of GLS for the prediction of mortality was 0.76 (95% CI 0.67 to 0.87). Patients with GLS > − 14.1 % showed a significantly higher mortality rate (67.7% versus 15.6%; p < 0.0001 ; log ‐ rank = 23.3 ; p < 0.0001). In the multivariate analysis, GLS (HR, 1.27; 95% CI 1.07 to 1.50, p = 0.005) and SOFA scores (HR, 1.27; 95% CI 1.08 to 1.50, p = 0.004) were independent predictors of in-hospital mortality. Conclusions. Our study indicated that LV systolic function measured by STE might be associated with mortality in patients with septic shock. [ABSTRACT FROM AUTHOR]

The ice-phobic and transparent surface based on the distinctive structure of a coating material has been investigated. Moth eye structure fabricated on the quartz substrate was covered with a flat paraffin layer to isolate it in a cold and humid environment. Paraffin wax was chosen as the coating material due to low thermal conductivity, easy coating, and original water repellency. The paraffin layer only stayed on the top of the nanostructure, separated it from the outside environment to obstruct heat energy being transferred to the cold substrate, and prevented the wetting transition, which was observed regularly on the rough surface. The uncountable number of air blocks trapped inside the nanostructure also contributed to delayed heat transfer, leading to an increase in the freezing time of the attached water droplet. The anti-icing performance was evaluated in terms of adhesion strength, freezing time, and freezing rain sustainability. The nanostructure coated sample was compared with barely coated and superhydrophobic nanostructure surface and demonstrated a preeminent performance. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to evaluate the efficacy of the treatment of knee osteoarthritis (OA) patients by using microfracture technique in combination with autologous bone marrow stem cell transplantation. METHODS: A clinical study was conducted between November 2011 and January 2015 and involved 46 patients (aged from 46 to 69) with primary knee OA grade II and III (according to Kellgren-Lawrence classification) at the Orthopedic Trauma Department, Vietnam-Germany Friendship Hospital. Patients were randomly assigned to receive knee arthroscopy and then bone-marrow stem cells from their pelvic bones via injection. RESULTS: The mean Visual Analogue Scale (VAS) score of present pain decreased from 5.68 before surgery to 1.7 24 months after surgery. The mean preoperative Knee Injury and Osteoarthritis Outcome Score (KOOS) was 36.34 (± 3.13), which increased to 74.62 (± 2.86) 24 months after surgery. On the MRI scans, the average Noyes score decreased from 12 (± 1.46) to 7 (± 1.50). Cartilage volume increased on average from 0.4512 (± 0.26) cm 3 to 0.5463 (± 0.29) cm 3 12–24 months after surgery. CONCLUSION: Treatment of osteoarthritis by a combination of arthroscopic microfracture and transplantation of autologous bone-marrow stem cells was an invasive, safe and effective method which showed an improvement in the clinical symptoms (VAS score) and knee functions (KOOS points). [ABSTRACT FROM AUTHOR]

The design method of an unequally spaced array was based on the density tapering in the textbook "Antenna theory" in 1969. The effects on grating lobe reductions were shown by radiation pattern calculations. However, no proof for the achievement of density tapering was shown. In this paper, through direct comparisons of the objective amplitude distribution with electric field distributions by electromagnetic simulation, density tapering is examined. A log-periodic dipole antenna operating from 900MHz to 2500MHz is designed for the array element. The unequally spaced 31-element array antenna is used for calculation. At many kinds of density tapering and many frequencies, calculated electric field distributions in a near-field region of the array antenna agree with the given density tapering distributions. The paper results show that the density tapering is achieved from 900MHz to 2000MHz and the effects of grating lobe reductions are ensured from 900MHz to 2500MHz. [ABSTRACT FROM AUTHOR]

By simply switching solvents, two sets of conditions for the total regio‐ and stereoselective photodimerization of (E)‐3‐(imidazo[1,2‐a]pyrimidin‐2‐yl)acrylic acid [(E)‐7a] have been found. In acetonitrile in the presence of benzophenone as photosensitizer or in cyclohexane, the head‐to‐head cis‐trans‐cis isomer 8a was the only observable cycloadduct. In DMSO, the head‐to‐head trans‐trans‐trans isomer 10a was obtained as the unique cycloadduct. The diester 9a, derived from 8a, was cyclized to the challenging, fully substituted diimidazobenzobutane system 13 present in benzosceptrins. The regio‐ and stereoselective photodimerization of (E)‐3‐(imidazo[1,2‐a]pyrimidin‐2‐yl)acrylic acid by sol switching is described. The diester was cyclized to the challenging, fully substituted diimidazobenzobutane system present in benzosceptrins. [ABSTRACT FROM AUTHOR]

[Display omitted] • Z-scheme CNBS@MnO 2 heterojunction with core–shell structures was fabricated. • The synergistic effect of CNBS@MnO 2 and PMS activation photodegrade diclofenac within 15 min. • O 2 ●−, ●OH and h+ are the primarily reactive radicals involved in visible-light-driven photodegradation. • CNBS@MnO 2 can maintain excellent recyclability and reusability after five successive runs. • The Z-scheme mechanisms with possible degradation pathways for diclofenac removal is proposed. In this study, the manganese dioxide (MnO 2) nanosheets were successfully embedded onto boron and sulfur co-doped g-C 3 N 4 (CNBS) nanotubes to construct the flower-like core–shell CNBS@MnO 2 heterojunction with Z-scheme structure for the enhanced photodegradation of diclofenac (DCF) in the presence of peroxymonosulfate (PMS) and 460-nm visible light. The CNBS@MnO 2 provides large specific surface area and reduced interfacial resistance for rapid electron transport. Moreover, the redox cycling of Mn species effectively activates PMS to produce sulfate radicals for DCF photodegradation. The PMS-based photodegradation of DCF over CNBS@MnO 2 displays the excellent photodegradation performance after 15 min of irradiation, and the efficiency is highly dependent on initial pH, ion species, and concentrations of PMS and DCF. The CNBS@MnO 2 also shows its excellent stability and reusability over ten cycles. Besides, h+, O 2 ●− and SO 4 ●− are the dominantly reactive species for the enhanced degradation of DCF over Z-scheme CNBS@MnO 2 heterojunction. The possible reaction mechanism as well as the degradation pathway of DCF over CNBS@MnO 2 in the presence of PMS is also proposed. Results clearly highlight the superior photoactivity of Z-scheme CNBS@MnO 2 toward micropollutant degradation by PMS activation, which can open an avenue to fabricate the g-C 3 N 4 nanotube@metal oxide structure as an effective activator for water and wastewater purification. [ABSTRACT FROM AUTHOR]

The floodplains play an important role in agricultural development and rural livelihoods in the Vietnamese Mekong Delta. As an intensive rice production area of Vietnam, the floodplain has experienced significant changes in water management regime during the recent decades. Depending on specific locations and irrigation infrastructure investments, four main water management practices have been innovated, particularly a planting season of two crops per year (2C1Y), three crops per year (3C1Y), three years eight crops (3Y8C) and two years five crops (2Y5C). The 4R framework (Reform, Result, Resilience, and Return) was developed based on grounded theory approach for resilience assessment of various innovative water management practices. In terms of resilience, we found that each crop pattern involves pros and cons, and the intensive crop practices are less resilient systems, especially in social, environmental, and ecological aspects. The findings provide good lessons learned not only for Vietnam but also for the other rice-producing deltas implementing ecosystem resilience to adapt to global challenges such as flood, drought, and salinity intrusion. [Display omitted] • The systems with more intensive crop patterns are less resilient. • The 4 R framework consisting of Reform, Result, Resilience and Return is developed. • Future policies should improve the livelihoods and enhance ecological resilience. [ABSTRACT FROM AUTHOR]

Various chemical oxidation techniques, such as potassium permanganate (KMnO 4 ), sodium persulfate (Na 2 S 2 O 8 ), Fenton (H 2 O 2 /Fe 2+ ), and the modified persulfate and Fenton reagents (activated by ferrous complexes), were carried out to treat marine sediments that were contaminated with polycyclic aromatic hydrocarbons (PAHs) and dredged from Kaohsiung Harbor in Taiwan. Experimental results revealed that KMnO 4 was the most effective of the tested oxidants in PAH degradation. Owing to the high organic matter content in the sediment that reduced the efficiencies of Na 2 S 2 O 8 and regular Fenton reactions, a large excess of oxidant was required. Nevertheless, KH 2 PO 4 , Na 4 P 2 O 7 and four chelating agents (EDTA, sodium citrate, oxalic acid, and sodium oxalate) were utilized to stabilize Fe(II) in activating the Na 2 S 2 O 8 and Fenton oxidations, while Fe(II)-citrate remarkably promoted the PAH degradation. Increasing the molecular weight and number of rings of PAH did not affect the overall removal efficiencies. The correlation between the effectiveness of the oxidation processes and the physicochemical properties of individual PAH was statistically analyzed. The data implied that the reactivity of PAH (electron affinity and ionization potential) affected its treatability more than did its hydrophobicity (K ow , K oc and S w ), particularly using experimental conditions under which PAHs could be effectively oxidized. [ABSTRACT FROM AUTHOR]

The oxidation of 16 polycyclic aromatic hydrocarbons (PAHs) compounds in sediments by sodium persulfate (Na2S2O8) simultaneously activated by temperature and nano zero-valent iron (nZVI) as the source of catalytic ferrous iron was investigated. The effect of various controlling factors, including S2O82−(0.017–170 g/L), nZVI (0.01–1 g/L), and temperature (50–70 °C) were performed. The efficiency to remove PAHs was 10.7–39.1% for unactivated persulfate. The treated sample had over 50% of the persulfate still remaining from an initial persulfate dose of 170 g/L, whereas less than 1% of the persulfate remained from an initial persulfate dose of 0.017, 0.17, and 1.7 g/L. Adequate persulfate (170 g/L) must be present because it is the source of the sulfate radicals responsible for the degradation of PAHs. Results indicated that increasing temperature and the addition of nZVI into a persulfate-slurry system could enhance the persulfate oxidation process. The best removal efficiency (90%) was achieved after 24 hr while adding nZVI (0.01 g/L) to persulfate (170 g/L) at temperature of 70 °C. The results suggested that nZVI assisted persulfate oxidation without elevating temperature may be a suitable and economic alternative for the ex situ treatment of PAH-contaminated sediments. Implications: Nano zero-valent iron (nZVI) has been successfully applied to transform/degrade contaminants in soils and water. Additionally, nZVI has been used as a catalyst to activate persulfate for the treatment of various contaminants. In this study, with the support of temperature, nZVI-persulfate oxidation system for treatment of PAH-contaminated sediments was improved significantly and the treated sediment could meet remediation goals. [ABSTRACT FROM PUBLISHER]

Abstract: Coordination polymers (metal–organic frameworks or MOFs) offer the opportunity for fine-tuning the luminescence behavior because of the possibility to entrap in the network pores molecules that can influence the lanthanide (Ln) emission. In this study, Zn (II) and polycarboxylate based MOFs were first pre-formed by solvothermal method, then considered as host-matrix for in situ doping of low-input concentration of Eu3+ and Tb3+ (two most commonly used lanthanides in life science assays), and afterwards lanthanide doped luminescent materials were synthesized. Different characterizations (X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive Spectroscopy (EDS)) were carried out to confirm accordingly MOF's crystallinity, the structure and chemical composition. The study on luminescent properties of the material has revealed an efficient energy transfer from the ligand excited states to the Eu3+ and Tb3+ f-excited states. With quite low input concentrations (8–15%) of doped rare earth ions, these complexes displayed intense emissions at room temperature and proved to be good candidates for red and green emitter luminescent materials. Generally, this design concept can be extended for the preparation of other rare earth coordination polymers. [Copyright &y& Elsevier]

New isoxazolidines were synthesized in good to excellent yields by I ,3-dipolar cycloaddition of N-vinylamide dipolarophiles and nitrones. Strikingly, solvent-free conditions gave high conversion and yields, shortened reaction time, and minimized degradation products. N-Vinyloxazolidin-2-one and its analogues used in these cycloaddition reactions were conveniently prepared in excellent yields by a modified version of Buchwald's one-step copper-catalyzed vinylation using vinyl bromide. From the adducts, a two-step access to various unsymmetric aspartate derivatives was also described. [ABSTRACT FROM AUTHOR]

Let G be the class of all nondecreasing functions from N to N. We shall define a partial order on G and classify the class of all quasi-games fairer with time into a nondecreasing family of subclasses, directed by g ∈ G for which the smallest element coincides with the set of all games fairer with time. [ABSTRACT FROM AUTHOR]

In this study, we conducted a facile method to fabricate an anti-icing surface on elastomer thin film by combining the PDMS nanostructure with the low surface tension lubricant. PDMS solution was mixed with slippery lubricant Krytox 1506 in a rational concentration and followed by a plasma dry etching process to promote the anti-icing performance in terms of shear stress and water repellency ability. Experimental results were compared with the reference substrates and demonstrated the advantages of the slippery surface in all mentioned scenarios. In addition, the functionalized surfaces also present high durability and good transparency, demonstrating a new facile method and design for outdoor anti-icing devices. • Have reinforced the ice repellency performance in several scenarios. • Nanostructure exhibited a good affinity with low surface tension lubricant while maintaining good transparency. • Liquid infused nanostructure of elastomer-based materials for outdoor applications have been considered. [ABSTRACT FROM AUTHOR]

Tetrasubstituted 2,3‐trans‐dihydrofuran and furan are important heterocyclic scaffolds in natural product, bioorganic and medicinal chemistry as well as in material science. The synthesis of both of these heterocycles starting from common and readily available starting materials are challenging. We found that in situ generated deoxybenzoin‐chalcone Michael adducts underwent oxidative annulation upon heating with molecular iodine in DMSO to provide selectively 2,3‐trans‐dihydrofurans at 80 °C and furans at 120 °C. [ABSTRACT FROM AUTHOR]

In the presence of a base catalyst (20 mol %) such as DBU, DABCO or Na2S ⋅ 3H2O/N‐methylpyrrolidone, phenylacetylenes were found to efficiently undergo sulfurative amination with elemental sulfur and anilines under neat conditions, leading to N‐aryl thioamides with complete atom efficiency. [ABSTRACT FROM AUTHOR]

Femtosecond time-resolved pump–probe absorption kinetic spectroscopy was used to show that the presence of plasmonic silver nanoparticles in Ag–CuPc hybrid thin-fi lm nanocomposites leads to a significant reduction in the relaxation time of induced absorption from an excited singlet state of copper phthalocyanine fi lm as compared to the pure fi lm. The observed effect is associated with intersystem crossing acceleration in CuPc molecules located in a nonuniform field near the surface of plasmonic silver nanoparticles in the hybrid nanocomposite. The detected effects were demonstrated to depend on the thickness of the copper phthalocyanine layers in the hybrid (Ag–CuPc)nAg nanocomposites. [ABSTRACT FROM AUTHOR]

In this study, the superconducting properties of MgB 2 bulk samples fabricated at different conditions were investigated. Ex situ MgB 2 samples were further mixed with Mg and B at different amounts and sintered at different times and temperatures. Using Raman spectroscopy, the bearing of electron-phonon (e-ph) coupling (EPC) has been investigated. The dependence of temperature on magnetization, M(T), along with the dependence of magnetic field on magnetization, M(H), were evaluated to analyze the superconducting characteristics. Using the McMillan formular, which is modified by Allen–Dynes, and the frequency of phonon located in the mid peak centre ω 2 (E 2g), the contribution of EPC, whose value is closely proportional to the variation of critical temperature was reckoned. The lowest EPC value was determined by Raman spectrum analysis to be 1.094 for the MgB 2 sample added with 0.5 Mg and sintered at 1000 °C for 1 h. In addition, the sample showed the lowest critical temperature along with the highest critical current density. The small bundle field (B sb) as well as the large bundle field (B lb) were obtained using the collective pinning theory, demonstrating the expansion of the small also the large bundle regimes under suitable sample fabrication conditions. Based on the dependence of temperature on normalized critical current density (j) and normalized small bundle field (B sb), δT c pinning is the predominant flux pinning mechanism across totally MgB 2 bulk samples. The model of Dew–Hughes confirmed that the addition of Mg along with B creates surface pinning in the matrix by analyzing the pinning properties. [ABSTRACT FROM AUTHOR]

The impact of adding SnO 2 nanoparticles on the enhancements of critical current density (J c) of the Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+ δ superconductors was studied. Polycrystalline superconductors with stoichiometry of (Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+ δ) 1− x (SnO 2) x where was x was ranged from 0.000, 0.002, 0.004, 0.006, 0.008 to 0.010 were made through traditional solid state reaction technique. X-ray diffraction data revealed that all fabricated samples consisted of Bi-2223 and Bi-2212 superconducting phases. The volume fraction of the Bi-2223 phase decreased with SnO 2 addition. Analyses of textural structure using scanning electron microscopy data evidenced a clear decrease in grain orientation and porosity with increased doping levels. SnO 2 presence in connection to Bi-2223 deceleration reduced the critical temperature. Values of J c deduced from the magnetization hysteresis loops measured at different temperatures of 35 K, 45 K, 55 K, 65 K were found to enhance for the SnO 2 added samples. In the x = 0.002 samples, the field dependent J c achieved its maximum values. In order to have a deeper understanding in the improvements of flux pinning properties, small and large bundle fields were determined by using the collective pinning theory. The obtained values indicate the expansion of the two corresponding regimes with appropriate. By analyzing the dependence of normalized J c versus normalized critical temperature, the dominant flux pinning mechanisms in all samples were consistent with δl pinning. Besides, the addition of SnO 2 nanoparticles was likely to produce pinning centers in form of core point as evidenced by using the Dew–Hughes model. [ABSTRACT FROM AUTHOR]

TiO 2 doping content affects the critical temperature (T c) and the variations of local structure on Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+δ. The (Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+δ) 1-x (TiO 2) x samples were fabricated with the solid-state reaction process, where x = 0, 0.002, 0.004, 0.006, 0.008, and 0.01. The T c values of the samples were obtained by measuring resistivity versus temperature, indicating that T c gradually decreased with increasing doping content (x). To explain the obtained degradation of T c , carrier properties, role of interlayer coupling, and local structure were systematically investigated using Azlamozov–Larkin theory and its Lawrence–Doniach modification for strong anisotropic superconductors. The calculation of excess conductivity at the mean field region showed that the c-axis coherence length (ξ c) and the effective inter-layering spacing (d) increased with increasing doping content. X-ray diffraction patterns also showed that the bond distances increased with increasing TiO 2 content. The copper valence (V) and carrier concentration (p) of the samples were determined by analyzing the Cu L 2,3 -edge X-ray absorption near edge structure spectra. The values of V and p showed the same trend of decreasing with increasing x. A close correlation between the changes in local structure parameters and degradation of T c of (Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+δ) 1-x (TiO 2) x was then probably concluded. [ABSTRACT FROM AUTHOR]

We study the electronic excitation dynamics in ensembles of plasmonic gold nanorods (Au NRs), in view of the femtosecond transient absorption spectroscopy, and compare the results with the excitation dynamics of spherical Au nanoparticles (NPs). We use the obtained kinetics of the transient absorption of Au NRs and Au NPs to fit the theoretical profile of the temperature relaxation of the excitation dynamics of electron and lattice nanoparticles, as well as their environment under the excitation by laser pulses with duration of 150 fs. For gold nanorods, the electron–phonon interaction constant reads γNRs = 12 · 1016 W·m−3·K−1, and the heat loss is hNRs = 16 · 108 W·m−2·K−1. In the case of gold nanospheres, the constants are γNPs = 7· 1016 W·m−3·K−1 and hNRs = 8· 108 W·m−2·K−1, respectively. [ABSTRACT FROM AUTHOR]

Using first‐principles density functional theory, we investigated the electronic and optical properties of monolayer and multilayer nanosheets of molybdenum carbon fluoride (Mo2CF2), a two‐dimensional (2D) transition‐metal carbide MXene. The indirect band gap of the Mo2CF2 semiconductor can be engineered by controlling the number of layers where the band gap energy changes from 0.278 eV for the monolayer to 0.249 eV for the trilayer nanosheet. The decrease in band gap energy in the multilayer is due to interlayer coupling, which splits the bands according to the number of layers. Mo2CF2 behaves as a metal with an anomalous dispersion and high optical conductivity at incident photon energies of 0.68–2.19, 3.49–6.68 and 7.30–8.31 eV. It has a relatively low reflectivity and is absorbing over a broad range of photon energies from about 0.429 (2890), 0.387 (3204) and 0.345 eV (3594 nm) for the monolayer, bilayer and trilayer nanosheets, respectively, achieving peak absorption in the vacuum ultraviolet region at about 7.9 eV (157 nm). The optical properties of Mo2CF2 can likewise be tuned by varying the number of layers. The unique behavior of its optical properties along with the ability to control its electronic and optical properties enhances the potential of 2D Mo2CF2 for various applications in the fields of electronics and energy storage. [ABSTRACT FROM AUTHOR]

Hair thinning and loss are prominent aging phenotypes but have an unknown mechanism. We show that hair follicle stem cell (HFSC) aging causes the stepwise miniaturization of hair follicles and eventual hair loss in wild-type mice and in humans. In vivo fate analysis of HFSCs revealed that the DNA damage response in HFSCs causes proteolysis of type XVII collagen (COL17A1/BP180), a critical molecule for HFSC maintenance, to trigger HFSC aging, characterized by the loss of stemness signatures and by epidermal commitment. Aged HFSCs are cyclically eliminated from the skin through terminal epidermal differentiation, thereby causing hair follicle miniaturization. The aging process can be recapitulated by Col17a1 deficiency and prevented by the forced maintenance of COL17A1 in HFSCs, demonstrating that COL17A1 in HFSCs orchestrates the stem cell-centric aging program of the epithelial mini-organ. [ABSTRACT FROM AUTHOR]

The effects of adding TiO 2 nanoparticles on the flux pinning properties of the Bi–Pb–Sr–Ca–Cu–O (BPSCCO) system were investigated. Polycrystalline samples of (Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O 10+δ) 1-x (TiO 2) x , where x = 0.000, 0.002, 0.004, 0.006, 0.008, and 0.010, were fabricated by the conventional solid-state reaction method. The X-ray diffraction (XRD) results showed that all samples consisted of Bi-2223 and Bi-2212 phases. The Bi-2223 volume fraction decreased with the addition of TiO 2. Scanning electron microscopy (SEM) examination presented a degradation in texture structure with increasing misoriented grain and porosity with high doping contents. The critical temperature was decreased by TiO 2 appearance in relation to Bi-2223 deceleration. Critical current density dependence on the magnetic field J c (B) was enhanced with x = 0.002, 0.004 and reached maximal values on the x = 0.002 sample. In the collective pinning theory framework, the small bundle field (B sb) and the large bundle field (B lb) were estimated, revealing the extension of the small and large bundle regimes with proper amounts of dopant. The temperature-dependent normalized critical current density (j) indicated that δl pinning is the dominant flux pinning mechanism in all samples. The Dew-Hughes model analyzed the pinning center properties and confirmed that TiO 2 nanoparticles create normal core point pinning centers in the matrix. [ABSTRACT FROM AUTHOR]

Soil salinity has a major impact on agricultural production. In a changing climate with rising sea-levels, low-lying coastal areas are increasingly inundated whereby saltwater gradually contaminates the soil. Drought prone areas may suffer from salinity due to high evapotranspiration rates in combination with the use of saline irrigation water. Salinity is difficult to monitor because soil moisture affects the soil's spectral signature. We conducted Fourier-transform infrared spectroscopy on alluvial and sandy soil samples in the coastal estuary of the Red River Delta. The soils are contaminated with NaCl, Na2CO3 and Na2SO4 salts. In an experiment of salt contamination, we established that three ranges of the spectrum were strongly influenced by both salt and moisture content in the soil, at wavenumbers 3200–3400 cm−1 (2.9–3.1 µm); 1600–1700 cm−1 (5.9–6.3 µm); 900–1100 cm−1 (9.1–11.1 µm). The Na2CO3 contaminated soil and the spectral value had a linear relationship between wavelengths 6.9 and 7.4 µm. At wavelength 6.99 µm, there was no relationship between absorbance and soil moisture, but the absorbance was proportional to the salt content (R2 = 0.85; RMSE = 0.68 g) and electrical conductivity (R2 = 0.50; RMSE = 3.8 dS/m). The relationship between soil moisture and spectral absorbance value was high at wavelengths below 6.7 µm, resulting in a quadratic relation between soil moisture and absorbance at wavelength 6.13 µm (R2 = 0.80; RMSE = 5.2%). The spectral signatures and equations might be useful for mapping salt-affected soils, particularly in difficult to access locations. Technological advances in thermal satellite sensors may offer possibilities for monitoring soil salinity. [ABSTRACT FROM AUTHOR]

The mechanism of the nonlinear optical response of colloidal solutions of Ag2S quantum dots passivated with thioglycolic acid molecules is considered. Appearance of nonlinear absorption and nonlinear refraction is shown by the Z-scan method using 10-ns pulses of the second harmonic of a Nd:YAG laser. The absorption coefficient dependence was found to saturate with increasing incident radiation intensity. It is suggested that nonlinear absorption occurs with participation of the localized states of structural defects in Ag2S, including the defect luminescence center, which is confirmed by femtosecond transient absorption spectroscopy. A broad structureless transient absorption band is observed in the range of 500–1000 nm, which decays on a time scale of picoseconds. It is concluded that the transient absorption signal is caused by fast (fractions of picoseconds) capture of charge carriers by localized states, which then induce the nonlinear absorption of 10-ns pulses. [ABSTRACT FROM AUTHOR]

Abstract: ZnO:In films are successfully prepared by using the electrostatic spray deposition technique. X-ray diffraction indicates that the ZnO:In films have a polycrystalline hexagonal wurtzite structure with lattice parameters  Å and  Å. Photoluminescence properties of the films are investigated in the temperature range of 11.6–300 K, showing strong luminescence in the whole range of temperature. The temperature dependence of the photoluminescence are carried out with full profile fitting of spectra, which clearly shows that the ultraviolet (UV) emission in In-doped ZnO films at low temperature are attributed to emission of a neutral donor-bound exciton (D∘X) and recombination of donor–acceptor pairs (DAP), while the UV emission at room temperature originates from radiative transition of an electron bound on a donor to the valence band. [Copyright &y& Elsevier]

In the present article, the synthesis of zeolite imidazolate framework-67/reduced graphene oxide (ZIF-67/rGO) and voltammetric determination of Rhodamine B (RhB) are demonstrated. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption/desorption isotherms. It was found that the ZIF-67/rGO composite consists of ZIF-67 nano-particles highly dispersed on the rGO matrix and possesses a high specific surface area. Because of the synergistic effect of good conductivity of rGO and high surface area of ZIF-67, the ZIF-67/rGO—modified glassy carbon electrode exhibits good electrochemical behavior toward Rhodamine B (RhB) oxidation. The use of this electrode to quantitate RhB with differential pulse voltammetric method was successful with a broad linear range, from 0.96 to 44.07 μg.L-1 of RhB and a low limit of detection of 1.79 μg.L-1. The procedure was able to be applied to quantitatively determine RhB content in several food samples with an exceptional recovery rate (98-103%). The quantitative results highly agreed with that provided by high-performance liquid chromatography, revealing that this material is promising in in situ monitoring of other illegal additives in food. [ABSTRACT FROM AUTHOR]

An international panel of movement disorders specialists explored the views and perceptions of people with Parkinson's disease (PD) about their condition and its treatment, including the potential mismatch between the clinician's view of the patient's condition and their own view of what aspects of the disease most affect their daily lives. The initiative was focused on Asian countries, so participants comprised experts in the management of PD from key centers in Asia, with additional insight provided by European and the North American movement disorders experts. Analysis of peer-reviewed publications on patient perceptions of PD and the factors that they consider important to their wellbeing identified several contributing factors to the mismatch of views, including gaps in knowledge of PD and its treatment, an understanding of the clinical heterogeneity of PD, and the importance of a multidisciplinary approach to patient care. The faculty proposed options to bridge these gaps to ensure that PD patients receive the personalized treatment they need to achieve the best possible outcomes. It was considered essential to improve patient knowledge about PD and its treatment, as well as increasing the awareness of clinicians of PD heterogeneity in presentation and treatment response. A multidisciplinary and shared-care approach to PD was needed alongside the use of patient-centered outcome measures in clinical trials and clinical practice to better capture the patient experience and improve the delivery of individualized therapy. [ABSTRACT FROM AUTHOR]

The nanostructured particles of europium(III) complexes with tri-n-octyl phosphineoxide (TOPO) and naphthoyl trifluoroacetone (NTA) ligands containing gold nanoparticles (GNPs) were successfully prepared by using the modified Stöber method. Their morphologies and optical properties were investigated. The results show that they are stable in aqueous solution. The TEM image indicates that the average diameter of nanoparticles of europium(III) complexes containing GNPs is about 115 nm. Monosize nanospheres containing GNPs of 18 nm were produced. The nanostructured luminescent complexes of europium(III) integrated with plasmon structure of GNPs exhibit efficient luminescence properties. [ABSTRACT FROM AUTHOR]

Background: Amid the global transition to treat opioid addiction as an illness, many people who inject drugs (PWID) face heterogeneous legal environments that include both punitive and harm reduction measures. In Vietnam, many PWID, who have a high burden of HIV, are sent to drug treatment centers, or "06 centers", for compulsory detoxification, vocational training, and labor for up to four years. This study investigates the challenges and facilitators of reentry into community and family life among men who are released from "06 centers" and provides insights and recommendations for developing policies and interventions that address special needs of this vulnerable population.Methods: In-depth interviews were conducted in 2011 by trained interviewers among a sample of 43 male PWID released within the past 2 years from "06 centers" in Hanoi, Vietnam to investigate the above issues and to recommend potential interventions. Participants were recruited from outpatient HIV clinics that serve PWID (n=22) and through peer referral from self-help groups for PWID (n=21). Interviews were audiotaped, transcribed, translated, entered into Atlas.TI qualitative data analysis software and analyzed for key themes.Results: The interviews revealed persistent drug-related stigmatization, frequently paired with HIV-related stigmatization and discrimination, which hindered employment, increased participants' social isolation and exacerbated their struggles with addiction. Families were participants' primary source of financial, employment, and emotional support, but addiction-related family tensions also had negative psychological effects. Participants identified methadone maintenance treatment as an effective means of overcoming addiction, yet few could fully benefit from this treatment due to its limited availability.Conclusion: Our study suggests that PWID released from "06 centers" would greatly benefit from the scale-up of community-based harm reduction measures that include addiction and HIV treatment, coupled with employment-support and family centered mental health services. [ABSTRACT FROM AUTHOR]

Background Amid the global transition to treat opioid addiction as an illness, many people who inject drugs (PWID) face heterogeneous legal environments that include both punitive and harm reduction measures. In Vietnam, many PWID, who have a high burden of HIV, are sent to drug treatment centers, or “06 centers”, for compulsory detoxification, vocational training, and labor for up to four years. This study investigates the challenges and facilitators of reentry into community and family life among men who are released from “06 centers” and provides insights and recommendations for developing policies and interventions that address special needs of this vulnerable population. Methods In-depth interviews were conducted in 2011 by trained interviewers among a sample of 43 male PWID released within the past 2 years from “06 centers” in Hanoi, Vietnam to investigate the above issues and to recommend potential interventions. Participants were recruited from outpatient HIV clinics that serve PWID ( n = 22) and through peer referral from self-help groups for PWID ( n = 21). Interviews were audiotaped, transcribed, translated, entered into Atlas.TI qualitative data analysis software and analyzed for key themes. Results The interviews revealed persistent drug-related stigmatization, frequently paired with HIV-related stigmatization and discrimination, which hindered employment, increased participants’ social isolation and exacerbated their struggles with addiction. Families were participants’ primary source of financial, employment, and emotional support, but addiction-related family tensions also had negative psychological effects. Participants identified methadone maintenance treatment as an effective means of overcoming addiction, yet few could fully benefit from this treatment due to its limited availability. Conclusion Our study suggests that PWID released from “06 centers” would greatly benefit from the scale-up of community-based harm reduction measures that include addiction and HIV treatment, coupled with employment-support and family centered mental health services. [ABSTRACT FROM AUTHOR]