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Phenols are toxic products derived from a wide range of industrial activities and the entry of these contaminants into the environment is seriously hazardous for both human and aquatic ecosystems. This study presents the use of a phenol-degrading consortium surrounded in an innovative "Small Bioreactor Chambers" (SBCs) along with biostimulation for phenol bioremediation from contaminated groundwater. To investigate the effect of biostimulation, synthesized-calcium peroxide (Ca02) nanoparricies were applied. The phenol-degrading consortium, was successfully isolated froni a water well located in Iran. The highest growth rate and phenol degradation of the ph100-consortium were observed at 15 °C and pH 7.5 in the presence of 500 mg·L-1 of powdered CaO2 and 100 mg·L-1 of phenol as a sole source of carbon. Next-generation sequencing (NGS) analysis of the consortium revealed that Proteobacteria and Bacteroidetes with 75.3% and 16.2% relative abundance were the dominant phyla in the ph100-consortium, respectively. Experimental results indicated that 100% of the contaminant (100 mg·LF) was successfully removed from groundwater using encapsulated CaO2 within 60 days with the negligible negative impacts on the microbial population. Furthermore, the highest biodegradation percentage were achieved during incubation of SBCs a medium supplemented with 500 mg·L-1 CaO2 Powder in 25th days of experiment. These results provide certain evidence for a successful simultaneous application of biostimulation and bioaugmentation processes through SBCs for contaminated water treatinent. [ABSTRACT FROM AUTHOR]

In this work, the binder-free Fe-doped cobalt LDH/nickel foam (CoFe LDH/NF) electrode was prepared using the hydrothermal method. To achieve higher electrocatalyst activity of CoFe LDH/NF, sulfurization was conducted using the hydrothermal method, while the phosphidation was performed through a chemical vapor deposition (CVD) technique. The CoFeS/NF and CoFeP/NF electrodes exhibited significantly higher electrocatalytic activity than CoFe LDH/NF electrode. The CoFeP/NF electrode with a specific surface area of 6.8 m2 g−1 had lower overpotentials of 120 and 236 mV for hydrogen (HER) and oxygen (OER) evolution reactions, respectively. Additionally, the CoFeP/NF electrode exhibited a low potential of 1.32 V vs. RHE at a current density of 10 mA cm−2 for urea oxidation reaction (UOR). The CoFeP/NF electrode demonstrated low overpotentials of 224 and 273 mV in a seawater solution for HER and OER, respectively. The density functional theory (DFT) calculations confirmed the experimental results in which the CoFeP/NF material had promising electrocatalytic activity for renewable energy applications. • CoFe LDH/nickel foam electrode was sulfurized and phosphorized for water splitting. • Sheet-like morphology of CoFeP and CoFeS materials was similar to CoFe LDH. • CoFeP/NF showed higher water splitting performance than the CoFeS/NF electrode. [ABSTRACT FROM AUTHOR]

The complexity of geo-materials' behaviors surpass the capabilities of conventional numerical methods alone, particularly when realistically modeling rock structures. Coupling methods can enhance the realism of numerical modeling. Discontinuous deformation analysis (DDA) and displacement discontinuity method (DDM) are combined to model block displacement and crack propagation mechanisms in a blocky rock mass. DDA calculates stresses, strains, rotations, and displacements of the blocks, while DDM predicts crack propagation paths based on specified boundary conditions. The displacements result from DDA are transformed into stresses, followed by investigating crack propagation mechanisms within each block using Kelvin's solution. Boundary stresses are adjusted as cracks propagate, updating stress boundary conditions in DDA. This iterative process continues until crack propagation halts or a new block emerges. In this paper, the complete failure process of a rock slab with one pre-existing non-persistent joint located on the crest of a rock slope and compression test on the rock-like specimen with a single random crack with a 45 ° slope angle is simulated using the proposed numerical approach. The proposed numerical solution is compared with existing numerical results. This comparison confirms the accuracy and effectiveness of the proposed procedure, as the predicted crack propagation paths from the coupled numerical method align well with the corresponding numerical results from the rock-like samples. [ABSTRACT FROM AUTHOR]

The hydrogen gas sensing properties of carbon-doped ZnO nanotube has been theoretically investigated by employing first-principles density functional theory in combination with non-equilibrium Green's function. The figure of merits is creating the new states in ZnO nanotube structure by adding carbon substitution for an oxygen site. The calculation of adsorption energy indicates strong chemical adsorption of hydrogen on the outside and inside of carbon-doped ZnO nanotube. Moreover, density of state, current-voltage and sensor response have been performed for energetically favorable adsorption geometries of hydrogen. The involvement of carbon valence electrons in the chemical adsorption of hydrogen has been examined by partial density of state diagram. The current-voltage diagram of carbon-doped ZnO nanotube indicates negative-differential resistance trend. This trend has been disappeared after the chemical adsorption of hydrogen. The sensor response calculations reveal the high response of the sensor occurs in 3.5 V on the outside and inside of carbon-doped ZnO nanotube. • Investigation of energy adsorption and transfer properties of carbon-doped ZnO nanotube. • Strong chemical adsorption of hydrogen on the outside/inside of carbon-doped ZnO nanotube. • New states are observed in local density of state (LDOS) after the addition of carbon doping. • Examination of negative-differential resistance in I–V curves of carbon-doped ZnO nanotube. • High sensor response is occurred in voltage of 3.5 V. [ABSTRACT FROM AUTHOR]

Blocks of different sizes are formed in a typical rock mass and affect its stability. The size difference in between the blocks consisting a rock mass is also important from the rock stability point of view. In this paper, the effects of external loading changes on the rock blocks displacements in the DDA method has been studied. The effects of external forces on the stability of the blocky rock mass not only depends on the magnitude of the applied forces but also depends on the dimensions of the blocks constituting the rock mass. In this research, an attempt has been made to examine the effects of centralized external forces on the stability of a blocky system via the definition of the External Force Index. The intensity of its effects on the displacement accuracy with respect to the time step length was analyzed and its relation with the analysis time is also investigated. It has been shown that accuracy of the displacement analysis of horizontal sliding block has an initial disturbance and is a function of the number of time steps, time interval and the EFI. In addition, the relation between the analysis time and EFI has also been studied. [ABSTRACT FROM AUTHOR]

Diabetes Mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia, which occurs due to insufficient production of insulin by the pancreas or resistance to insulin produced by the body. The most dangerous and Long-term complications of diabetes include renal failure, heart failure, cardiovascular disease, stroke, diabetic foot ulcers, and diabetic neuropathy. This longitudinal cohort study was conducted on 1641 non-diabetic people of 2000 participants enrolled in phase I of Yazd Healthy Heart project (YHHP) aged 20-74 year-old resident of the city of Yazd. They were selected randomly through cluster sampling method and included in follow up a project for ten years (2004–2014). In order to analyze the data, Chi-Square, independent t -test and logistic regression statistical models were used through the SPSS Ver 20. The incidence rate of DM type II among the people aged 20–74 years in Yazd was 21.4 per 1000 of a population-year. Univariate analysis revealed that the relative risk of DM incidence increased by smoking, increasing BMI, abdominal obesity, hypertension, and increased cholesterol, triglyceride and uric acid levels (p < 0.0001). Variables with a significant p-value < 0.05 using the univariate analysis were included in the logistic regression model. Age, family history of diabetes mellitus in relatives, abdominal obesity, triglyceride values greater than 150 and uric acid more than the 75th percentile were recognized as independent risk factors of diabetes. In the present study, Age, family history of DM, abdominal obesity, high triglycerides, and high uric acid are the most important risk factors for diabetes. [ABSTRACT FROM AUTHOR]

Highlights • Forming and installing all-steel tubular buckling restrained brace (STBRB) is easy. • Incorporating pods significantly improves the seismic performance of the STBRBs. • Pods increase the buckling capacity of STBRBs from 40% to 150%. • Braces with tubular pods have ~2.5–10 times more energy dissipation than without pods. [ABSTRACT FROM AUTHOR]

Tsukamurella is an aerobic, Gram-positive and nonmotile bacterium. It was first isolated in 1941 from the mycetoma and ovaries of the bedbug. The primary strains were named Corynebacterium paurometabolum and Gordona aurantiaca and are different from the Collins et al. , 1988 classification of the new Tsukamurella genus. Human infections with Tsukamurella species are rare because the species is a kind of saprophyte bacterium; however, most information regarding this species comes from case reports. Molecular markers for the identification Tsukamurella include sequencing of 16S rRNA, groEL, rpoB, secA1 and ssrA genes. Given the lack of information on the treatment of Tsukamurella infections, a combination of various antibiotic agents is recommended. [ABSTRACT FROM AUTHOR]

The combustion synthesis of elemental Mo nanoparticles by zincothermic reduction of MoO 3 was investigated in this research. It was determined that MoO 3 reduces to Mo by means of two sub-reactions. The results showed that MoO 3 reduces initially to MoO 2 and subsequently dioxide phase reduces to elemental Mo. Due to the formation of MoO 2 during the combustion moment, a considerable amount of unwanted Zn 2 Mo 3 O 8 (2ZnO·3MoO 2 ) phase was synthesized. Since the presence of this phase would prevent the reduction to be completed, hence this article was devoted to introduce some ways by which the zincothermic reduction of MoO 3 can be completed. In one approach, the results indicated that by increasing the microwave heating duration after combustion moment, the unwanted Zn 2 Mo 3 O 8 compound reduced successfully to Mo. In the other approach, the use of over-stoichiometric amounts of Zn led to prevent the formation of the undesired phase. In this research, X-ray diffraction technique (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the products of the reactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of the ZrB2-based composite by magnesiothermic reduction of zircon. [•] Study of boron oxide amount on the triggering reaction. [•] Investigation of the carbon role on the reaction progression. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of zirconium diboride by magnesiothermic reduction. [•] Using high energy ball milling to perform mechanochemical reactions. [•] Study of mechanism of ZrB2 synthesis by studying subreactions and thermal analysis. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new route for the synthesis of WC–Al2O3 composite has been introduced. [•] WC–Al2O3 powder was synthesized by 6h milling of WO3–1.8Al–1.56C mixture. [•] Effect of process variables on crystallite size and lattice strain was studied. [•] High reaction intensity results in a large crystallite size and low lattice strain. [•] Longer milling times results in a smaller crystallite size and higher lattice strain. [ABSTRACT FROM AUTHOR]

Abstract: Due to the weak properties of W2C phase, its formation during the process of WC synthesis should be prevented. The aim of the present study has been the mechano-chemical synthesis of a WC–Al2O3 composite powder free from undesirable W2C phase through the addition of excess carbon to the WO3–2Al–C initial mixture. Based on the thermodynamic calculations and results of the supplementary experiments in W–yC and W2C–C systems, the possibility of the conversion of W2C to WC phase through the addition of excess carbon has been investigated. It has been shown that production of a WC–Al2O3 composite powder by 360min mechano-chemical treatment of an initial mixture of WO3–2Al–1.8C is possible. TEM observations and Williamson–Hall calculation revealed that the obtained WC–Al2O3 powder contains macro-size agglomerates in which each agglomerate consists of nano-size phases. [Copyright &y& Elsevier]

Abstract: Background: Knee osteoarthritis patients co-contract in knee-related muscle pairs during walking. The determinants of this co-contraction remain insufficiently clear. Methods: A heterogeneous group of 14 patients was measured before and one year after knee arthroplasty, and compared to 12 healthy peers and 15 young subjects, measured once. Participants walked on a treadmill at several imposed speeds. Bilateral activity of six muscles was registered electromyographically, and co-contraction time was calculated as percentage of stride cycle time. Local dynamic stability and variability of sagittal plane knee movements were determined. The surgeon''s assessment of alignment was used. Pre-operatively, multivariate regressions on co-contraction time were used to identify determinants of co-contraction. Post-operatively it was assessed if predictor variables had changed in the same direction as co-contraction time. Findings: Patients co-contracted longer than controls, but post-operatively, differences with the healthy peers were no longer significant. Varus alignment predicted co-contraction time. No patient had post-operative varus alignment. The patients'' unaffected legs were more unstable, and instability predicted co-contraction time in both legs. Post-operatively, stability normalised. Longer unaffected side co-contraction time was associated with reduced affected side kinematic variability. Post-operatively, kinematic variability had further decreased. Interpretations: Varus alignment and instability are determinants of co-contraction. The benefits of co-contraction in varus alignment require further study. Co-contraction probably increases local dynamic stability, which does not necessarily decrease the risk of falling. Unaffected side co-contraction contributed to decreasing affected side variability, but other mechanisms than co-contraction may also have played a role in decreasing variability. [Copyright &y& Elsevier]

BACKGROUND: Patients with knee osteoarthritis often feel unstable, suffering from buckling (giving way) or even falling. This study aimed at characterising such instability, and following it over time. METHODS: We investigated treadmill walking in knee osteoarthritis, focusing on angular velocity of sagittal plane knee movements. Knee osteoarthritis patients were followed 1 year after replacement surgery, and were compared to healthy peers. Subjects walked at increasing speeds, and maximum speed was registered. To quantify stability, we calculated short-term (lambda(S)) and long-term (lambda(L)) Lyapunov exponents (the exponential rate of divergence, in state space, of trajectories originating from nearest neighbours), as well as the variability of knee movements, the latter just after heel contact. At each measurement session, patients reported how often they had fallen in the preceding period. FINDINGS: Patients had lower maximum walking speed than controls, and walked with reduced variability, post-operatively even more so. Variability was positively related to number of falls. Pre-operatively, patients had higher lambda(S) at the unaffected side, which post-operatively normalized. INTERPRETATION: Slow walking may serve being more cautions. Reducing variability of sagittal knee kinematics appears to reduce fall risk, perhaps involving paying more attention and/or using cocontraction. The pre-operatively higher unaffected side lambda(S) could result from attempts to reduce the kinematic demands on the affected leg, 'letting go' the unaffected leg. One year after the operation, this problem with unaffected lambda(S) had disappeared, suggesting recovery. Further study should include short-term and long-term stability, as well as a quantitative measure of perceived instability. [ABSTRACT FROM AUTHOR]

Background: Patients with knee osteoarthritis often feel unstable, suffering from buckling (giving way) or even falling. This study aimed at characterising such instability, and following it over time. Methods: We investigated treadmill walking in knee osteoarthritis, focusing on angular velocity of sagittal plane knee movements. Knee osteoarthritis patients were followed 1year after replacement surgery, and were compared to healthy peers. Subjects walked at increasing speeds, and maximum speed was registered. To quantify stability, we calculated short-term (λ S) and long-term (λ L) Lyapunov exponents (the exponential rate of divergence, in state space, of trajectories originating from nearest neighbours), as well as the variability of knee movements, the latter just after heel contact. At each measurement session, patients reported how often they had fallen in the preceding period. Findings: Patients had lower maximum walking speed than controls, and walked with reduced variability, post-operatively even more so. Variability was positively related to number of falls. Pre-operatively, patients had higher λ S at the unaffected side, which post-operatively normalized. Interpretation: Slow walking may serve being more cautions. Reducing variability of sagittal knee kinematics appears to reduce fall risk, perhaps involving paying more attention and/or using cocontraction. The pre-operatively higher unaffected side λ S could result from attempts to reduce the kinematic demands on the affected leg, “letting go” the unaffected leg. One year after the operation, this problem with unaffected λ S had disappeared, suggesting recovery. Further study should include short-term and long-term stability, as well as a quantitative measure of perceived instability. [Copyright &y& Elsevier]

Abstract: In order to describe temporal evolution of BET surface area of a mineral substance during an intensive milling process, a mathematical model in the form of S = a + b e − mt + c e – nt has been developed based on well-established phenomena in mechanical activation processes. Validity of the proposed model was verified by the results of experiments performed on a natural chalcopyrite mineral as well as those reported in the literature on a variety of sulfide minerals. It was shown that the model could fit different types of surface area variation with a very good accuracy. [Copyright &y& Elsevier]

Abstract: Attempts have been made to develop a mathematical expression on the basis of dislocation theory to describe the effect of intensive milling time on the changes of dislocation density as well as amorphization degree of a mineral substance during intensive milling process. Validity of the proposed expression was verified by the results of experiments performed on a natural chalcopyrite mineral as well as those reported in the literature. It was concluded that the expression satisfied the experimental results with a good accuracy. [Copyright &y& Elsevier]

Abstract: In order to produce tungsten carbide from its oxide through mechanochemical process, a mixture of tungsten oxide, carbon and aluminum powders was subjected to high energy milling. Excess carbon addition was made in expense of aluminum, so that carbon acts not only as a carbide former agent but also as a reductant. Aluminum and carbon contents of the mixture were altered according to the following reaction: WO3 +(4−1.5x)C+ xAl=WC+(x/2)Al2O3 +(3−1.5x)CO(g). The value of x varied from 0.5 to 1.9 and the effect of Al content on the mechanism of tungsten carbide formation was investigated. Thermodynamic calculations revealed that the amount of Al in the mixture plays a key role. Experimental results showed that at lower Al content in the WO3–Al–C mixture (x =0.5–1.2), reactions proceed through a gradual mode. By increasing Al content (x =1.3–1.6), type of reactions changed to mechanically induced self-propagating reaction (MSR) with no carbothermic reduction reaction of WO3. Further increase of Al content (x =1.7–1.9) resulted in MSR mode reactions consisting of both aluminothermic and carbothermic reactions. Optimum value of x which yields maximum amount of WC was found to be around 1.7. Discussion has been made to elucidate the phase formation types in accordance with the above three reaction modes. [Copyright &y& Elsevier]

Abstract: Background: The purpose of this study was to evaluate the incidence rate of endometrial disease, particularly endometrial carcinoma, in patients with primary peritoneal serous papillary carcinoma (PSPC). Methods: Retrospective review of clinical and histological data from 32 women undergoing surgery (with hysterectomy) for stage III or IV PSPC. Results: Six patients underwent primary debulking surgery and 26 underwent interval debulking surgery after 3 or 4 courses of platinum-based chemotherapy. Six patients (18%) had endometrial disease (hyperplasia in four). Two patients had endometrioid adenocarcinoma of the uterine body (stage IA grade 1 in one case, and stage IB grade 1 in the other) associated with the PSPC. Conclusions: Endometrial carcinoma of the uterine body may be associated with PSPC (6% cases in the present series). This result suggests that systematic hysterectomy should be performed at the time of debulking surgery in PSPC, even in the absence of peritoneal spread within pelvic cavity. [Copyright &y& Elsevier]

Abstract: Cadmium is a toxic metal, which is primarily produced as a by-product from mining, smelting and refining of sulphide ore concentrates of zinc. Secondary cadmium is recovered from spent Ni–Cd batteries. Some cadmium is also recovered from zinc sinter plant fume, EAF dust, cadmium containing alloys, cadmium containing fluorescent materials, etc. In all cases cadmium is associated with some other impurities depending on the source. The hydrometallurgical processing is very effective for treating such materials because it can control the different levels of impurities. The most common lixiviant used to dissolve the desired metals is sulphuric acid. In the present paper, the hydrometallurgical processes have been described for the recovery of cadmium from various resources using sulphuric acid as the main lixiviant. The leach solution obtained has been purified using cementation or solvent extraction methods. The metal is then produced from the purified solution by electrowinning or precipitation with zinc dust and melting. [Copyright &y& Elsevier]

Abstract: Objective:: We compare the efficacy and late complications between a polypropylene monofilament tape (TVT) and a polypropylene multifilament tape (IVS) in the surgical implant of sub-urethral, tension free tape for the treatment of stress urinary incontinence (SUI). Methods:: It is a non-randomised, monocentric retrospective study. Two questionnaires were sent to the patients. The first questionnaire determined the efficacy of the tape and the tolerance of the urinary process. The second questionnaire evaluated discomfort and consequences linked to urinary incontinence and associated urinary troubles. Results:: The study included 313 female patients and 256 (82%) responded to the questionnaire (137 TVT, 119 IVS). Patient satisfaction was 88.3% for the TVT tape and 73.5% for the IVS tape (p <0.005). The improvement of the quality of life was also higher for the polypropylene monofilament tapes. “De novo” urge incontinence was more common in the TVT group. However, the rates of dysuria and infection of tapes were more common in the IVS group. Conclusion:: The type of tape appears to influence efficacy and the emergence of late complications. Our results point at the greater efficacy of the polypropylene monofilament tape. [Copyright &y& Elsevier]

The genus Rothia are emerging as opportunistic pathogens associated with various infections in immunocompromised and immunocompetent individuals. This review describes the taxonomy, cell wall structure, pathogenesis, phenotypic and molecular characteristics, clinical diseases, treatment and, as well as, the related genera that may be misidentified by Rothia species. • Rothia spp. are causing various infections in human. • Molecular identification is necessary for the genus and species level identification. [ABSTRACT FROM AUTHOR]