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A product design and development process has been adopted to study and improve the performance of unit cleaner system. A hair trimmer with liquid detergent in cartridge is fixed as a cleaner system to design and analyse. The 3D model of the system is designed with NX CAD software. The modification is cartridge unit is made on counter face to increase the turbulence of the fluid in the wash zone. The file has been extracted and imported in LS Dyna for meshing the model for detergent liquid flow analysis. The velocity vector and pressure magnitude of the fluid flow is analysed through a StarCCM+ higher fluid analysis software. The input process condition of the pump in cartridge assemble unit has a speed 2000 rpm and velocity of the liquid as 1 m/s. From the analysis, the suction pressure noticed at the pump zone is 950 Pa and the discharge of fluid in the pump is 850 – 900 Pa at wash zone. Difference in fluid velocity found decreased and it is in the range of 0.8 to 0.95 m/s. The predominant factor in the design is alternate openings in case baffle has increased the turbulence in pressure and the velocity of the fluid found same.

Degradation of silicon rubber due to heat and humidity affect its performance in outdoor applications. To analyze the effects of high temperature and humidity on room temperature vulcanized (RTV) silicone rubber (SiR) and its composites, this study was performed. Five different sample compositions including neat silicone rubber (nSiR), microcomposites (15 wt% silica(SMC 15% SiO2) and 15 wt% ATH(SMC 15% ATH), nanocomposite (2.5 wt% silica(SNC 2.5% SiO2) and hybrid composite (10 wt% micro alumina trihydrate with 2 wt% nano silica(SMNC 10% ATH 2% SiO2) were prepared and subjected to 70 ˚C temperature and 80% relative humidity in an environmental chamber for 120 h. Contact angle, optical microscopy and Fourier transform infrared (FTIR) spectroscopy were employed to analyze the recovery properties before and after applying stresses. Different trends of degradation and recovery were observed for different concentrations of composites. Addition of fillers improved the overall performance of composites and SMC 15% ATH composite performed better than other composites. For high temperature and humidity, the ATH-based microcomposite was recommended over silica due to its superior thermal retardation properties of ATH. It has been proved that ATH filler is able to withstand high temperature and humidity.

Efforts to generate organomanganese reagents under ball‐milling conditions have led to the serendipitous discovery that manganese metal can mediate the reductive dimerization of arylidene malonates. The newly uncovered process has been optimized and its mechanism explored using CV measurements, radical trapping experiments, EPR spectroscopy, and solution control reactions. This unique reactivity can also be translated to solution whereupon pre‐milling of the manganese is required., A manganese‐mediated reductive dimerization of arylidene malonates by ball milling is reported. The process has been optimised and its mechanism explored by CV measurements, radical trapping, and EPR spectroscopy. Control experiments identify the action of ball milling rather than mortar and pestle is necessary to realise the effective activation of manganese, which can then be used in either solution or a ball mill for subsequent reactions.

Efforts to generate organomanganese reagents under ball milling conditions have led to the serendipitous discovery that manganese metal can mediate the reductive dimerization of arylidene malonates. The newly uncovered process has been optimized and its mechanism explored using CV measurements, radical trapping experiments, EPR spectroscopy and solution control reactions. This unique reactivity can also be translated to solution where upon pre-milling of the manganese is required.

The western Himalayan region in northern Pakistan is one of the most sensitive hotspots to climate change, due to the rapidly increasing population and delicate mountainous ecosystem. The relatively limited observed instrumental record impedes our understanding of long-term climate variability and their assessment. Using standard dendrochronological techniques, a 395-year (1620 to 2014 C.E.) tree-ring chronology of Abies pindrow (Royle) (Himalayan fir) was developed from the western Himalayan region in northern Pakistan. The results of the growth-climate relationship demonstrated that the radial growth of Abies pindrow was limited by minimum temperature. Using a robust reconstruction model, a 310-year (1705 to 2014 C.E.) minimum temperature was reconstructed from the western Himalayan region in northern Pakistan. The reconstructed minimum temperature accounts for 38% variance of the actual minimum temperature, and provides the evidences of Dalton minimum and modern maximum periods. The coldest years in the reconstruction were 1726, 1727, 1892, 1921, and 2001, whereas the hottest years were 1789, 1807, 1814, 1846, 2011, and 2013. Multi-taper method (MTM) spectral analysis showed a significant shorter quasi-cycles (2.3 to 3.5 years) and decadal cycles (11.5 to 17.5 years), suggesting a possible teleconnections with El Nino Southern Oscillation (ENSO), and Northern Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) respectively.

Background and Aims At least 80% of children with steroid sensitive nephrotic syndrome (SSNS) have relapses and many are triggered by upper respiratory tract infections (URTIs). Previous small studies (4 studies, 232 patients in total), mostly in children already taking maintenance corticosteroid in countries where URTI epidemiology is different to Europe, showed that giving daily low-dose prednisolone for 5-7 days during an URTI reduces the risk of relapse. The objective of the PREDNOS 2 trial was to determine if these findings were replicated in a large UK population of children with relapsing SSNS on different background medication or none. Method A randomised, double-blind, placebo-controlled trial, including a model-based economic evaluation was carried out in 122 UK paediatric departments. Between February 2013 and January 2019, 365 children with relapsing SSNS (mean age: 7.6 ± 3.5 y) were recruited from 91 sites and randomised (1:1) according to a minimisation algorithm based on background treatment (no background treatment; low-dose prednisolone only; low-dose prednisolone and other immunosuppression; other immunosuppression only). At the start of an URTI, children received 6 days of prednisolone 15 mg/m2 or matching preparation of placebo. Those already taking alternate day prednisolone rounded their daily dose using trial medication to the equivalent of 15 mg/m2 or their alternate-day dose, whichever was the greater. The primary outcome was the incidence of first URTI-related relapse (URR) following any URTI over 12 months. Secondary outcomes were the overall rate of relapse, changes in background treatment, cumulative dose of prednisolone, rates of serious adverse events, incidence of corticosteroid adverse effects, change in Achenbach Child Behaviour Checklist score and quality of life. Analysis was by intention to treat. The economic evaluation used trial data and a decision-analytic model to estimate Quality-Adjusted-Life-Years (QALYs) and costs at 1-year, which were then extrapolated over 16 years. Results 80 children completed 12 m follow-up without an URTI. Consent was withdrawn for 32 children, 14 prior to an URTI, leaving a modified intention to treat analysis population of 271 children (134 and 137 in prednisolone and placebo arms respectively). There were 384 URTIs and 82 URRs in the prednisolone arm, and 407 URTIs and 82 URRs in the placebo arm. The number of patients experiencing a URR was 56 (42.7%) and 58 (44.3%) in the prednisolone and placebo arms respectively (adjusted risk difference: -0.024, 95% CI: -0.14 to 0.095; P=0.7). There was no evidence that the treatment effect differed when data were analysed according to background treatment. There were no significant differences in secondary outcomes between treatment arms. A post-hoc subgroup analysis assessing primary outcome in 58 children of South Asian ethnicity (RR 0.66, 95% CI: 0.396 to 1.105) versus 213 of other ethnicity (RR 1.11, 95% CI: 0.806 to 1.535) showed possible efficacy of intervention in those of South Asian ethnicity (test for interaction P=0.09). Giving daily prednisolone at the time of an URTI was found to increase QALYs and decrease overall costs, when compared to standard care, a finding that was robust to sensitivity analysis. Conclusion In a large and methodologically-robust study, PREDNOS 2 has shown that giving 6 days of daily low-dose prednisolone at the time of an URTI does not reduce the risk of relapse of nephrotic syndrome in UK children, but could offer a cost-effective use of health care resources. Further work is needed to investigate inter-ethnic differences in treatment response, and the pathogenesis of individual viral infections and their effect on nephrotic syndrome.

Silicone rubber is a promising insulating material that has been performing well for different insulating and dielectric applications. However, in outdoor applications, environmental stresses cause structural and surface degradations that diminish its insulating properties. This effect of degradation can be reduced with the addition of a suitable filler to the polymer chains. For the investigation of structural changes and hydrophobicity four different systems were fabricated, including neat silicone rubber, a micro composite (with 15% micro-silica filler), and nanocomposites (with 2.5% and 5% nanosilica filler) by subjecting them to various hydrothermal conditions. In general, remarkable results were obtained by the addition of fillers. However, nanocomposites showed the best resistance against the applied stresses. In comparison to neat silicone rubber, the stability of the structure and hydrophobic behavior was better for micro-silica, which was further enhanced in the case of nanocomposites. The inclusion of 5% nanosilica showed the best results before and after applying aging conditions.

The scope of silicone rubber (SiR) is confined due to the deprivation of its dielectric propertiesupon exposure to various ambient stresses. The aim of this research is to develop silicone rubber-based composites by employing inorganic oxide fillers for improved dielectric and high voltage insulation properties for widening its scope in the field of electrical appliances. This study reports the preparation of different composites of silicone rubber with varying concentrations of micro and nano-silica fillers. The dielectric propertytrends of these as-prepared neat and impregnated samples were examined via an indigenously developed weathering chamber capable of applying multiple stresses of acid rain, heat, humidity, UVA radiation, and salt fog. Dielectric constant values were measured before and after applying stresses. Upon applying stresses, a periodic decline in dielectric constant was observed. Improved dielectric properties were obtained by adding micro and nano-silica as fillers. A nano silica-incorporated silicone rubber product exhibited good potential for dual applications as dielectric and high voltage insulation.

This investigation reports the effect of magnetic field during coating on the mechanical properties of the electroless Ni–P deposits. Magnetic field strength has been varied between 0 and 3A. The heat treatment was found to be more responsive for the sintering temperature between 300 and 400 °C. Micro hardness of the electroless Ni–P deposits was measured with a diamond indenter. Magnetic method produced more hardness (above 1250 VHN) than the conventional method (below 1000 VHN). The amorphous phase to crystalline transformation happens at this range of sintering. The pin-on-disc wear tester was used to measure the wear resistance of the deposits. The coated sample has a maximum weight loss of 0.077 mg at the end of the wear test (after 35 min) and 0.052 mg for magnetic field sintered sample at the same condition. Subsequently, with respect to increase in sintering temperature, the weight loss found decreased from 0.077 to 0.051 mg for as coat to 350 °C, respectively. It is also noticed that, the specific wear rate is 0.062 (kg/Nm3) for magnetic field sintered sample and 0.119 (kg/Nm3) for conventional sample. The characteristics of deposits produced in presence of magnetic field were found to be superior from those produced using conventional deposition techniques. Magnetic field has doubled the performance than the conventional techniques. Enhancements in properties were correlated with modified crystallinity and the conversion of Ni–P in to possible phosphides in the presence of magnetic field.

Our understanding of the full range of natural variability in streamflow, including how modern flow compares to the past, is poorly understood for the Upper Indus Basin (UIB) because of short instrumental gauge records. To help address this challenge, we use Hierarchical Bayesian Regression (HBR) with partial pooling to develop six centuries long (1394–2008 C.E.) streamflow reconstructions at three UIB gauges (Doyian, Gilgit, and Kachora), concurrently demonstrating that HBR can be used to reconstruct short records with interspersed missing data. At one gauge (Partab Bridge), with a longer instrumental record (47 years), we develop reconstructions using both Bayesian Regression (BR) and the more conventionally used Principal Components Regression (PCR). The reconstructions produced by PCR and BR at Partab Bridge are nearly identical and yield comparable reconstruction skill statistics, highlighting that the resulting tree-ring reconstruction of streamflow is not dependent on the choice of statistical method. Reconstructions at all four reconstructions indicate flow levels in the 1990s were higher than mean flow for the past six centuries. While streamflow appears most sensitive to accumulated winter (January-March) precipitation and summer (MJJAS) temperature, with warm summers contributing to high flow through increased melt of snow and glaciers, shifts in winter precipitation and summer temperatures cannot explain the anomalously high flow during the 1990s. Regardless, the sensitivity of streamflow to summer temperatures suggests that projected warming may increase streamflow in coming decades, though long-term water risk will additionally depend on changes in snowfall and glacial mass balance.

Nickel-based superalloys are mostly used as gas turbine components. During combustion, the sodium sulphate and sodium chlorides with vanadium pentoxide are dominating corrosive species in gas turbi...

The efficiency of industry depends upon the working conditions of the equipment and components used in the industrial process. The biggest problems faced by the industries are the problems of erosion and corrosion. The harmful effects of corrosion will lead to material loss, which results from the degradation of the equipment. The degradation of the equipment will cause the breakdown of the plant; moreover, it is a threat to the safety of people, and also from the point of conservation, it can cause the exploitation of available resources. The cost of replacing equipment increases the expense, and it can also result in the temporary shutdown of the plant. The protection of surfaces from the adverse effects of corrosion and erosion-corrosion is a matter of great concern in most industrial applications. Advancements in technology provides a wide range of techniques to overcome adverse conditions. The selection of appropriate technology must be from the viewpoint of their interaction with the environment. This review paper addresses the adverse effects of erosion-corrosion in the present scenario.

The alumina based ceramic cutting tools are used to machine glass fibre reinforced plastic (GFRP) composite material and AISI D2 steel. The machining studies were conducted using Ti[C,N] mixed alumina based ceramic cutting tool (CC650) and SiC whisker reinforced alumina based ceramic cutting tool (CC670). Machining process was performed at different cutting speeds at constant feed rate and depth of cut and the flank wear of the cutting tools were measured. From the machining studies, the wear behaviour of the cutting tool are studied and compared with reference to the work material. Very smooth wear land was observed while machining GFRP composite whereas, ridges and groves were observed while machining steel using alumina based ceramic cutting tools. The hard metal chips produced during machining has induced to undergo the severe in changes on machining D2 steel. Based on the flank wear, tool face fibre / matrix chip has prone to maximum wear of 0.4mm compared to machining a metal. On machining AISI D2 steel the machining has reduced one fold (1:2) than the GFRP composite material. In summary, Ti[C,N] mixed alumina cutting tool performance better on machining AISI D2 steel and SiC whisker reinforced alumina cutting tool for machining GFRP composite.

The high temperature oxidation and hot corrosion behavior of nickel–iron-based superalloy are studied at 900 ° and 1000 °C. The significant role of alloying elements with respect to the exposed medium is studied in detail. The mass change per unit area was catastrophic for the samples exposed at 1000 °C and gradual increase in mass change was observed at 900 °C for both the environments. The exposed samples were further investigated with SEM, EDS and XRD analysis to study the metallurgical characteristics. The surface morphology has expressed the in situ nature of the alloy and its affinity toward the environment. The EDS and XRD analysis has evidently proved the presence of protective oxides formation on prolonged exposure at elevated temperature. The predominant oxide formed during the exposure at high temperature has a major contribution toward the protection of the samples. The nickel–iron-based superalloy is less prone to oxidation and hot corrosion when compared to the existing alloy in gas turbine engine simulating marine environment.

Purpose The aim of this paper is to study the hot corrosion behaviour of super 304H stainless steel for marine applications. Design/methodology/approach The investigation was carried out with three different combinations of salt mixture (Na2SO4, NaCl and V2O5) at two different temperatures (800 and 900°C). Findings The spalling and growth of oxide layer was observed more with the presence of V2O5 in the salt mixture at 900°C during experimentation than what was observed in 800°C. The mass change per unit area is calculated to study the corrosion kinetics and also the influence of salt mixture. Further, the samples are analysed through materials characterisation techniques using optical image, scanning electron microscope (SEM), energy dispersive X-ray (EDAX) and X-ray diffraction (XRD) analysis. The presence of V2O5 in the salt mixture was the most important influencing species for accelerating hot corrosion. Originality/value SEM, EDAX and XRD analysis confirmed the formation of Fe2O3 and Cr2O3 at 900°C showing contribution in corrosion protection.

The recent research in biocompatible materials has been useful in replacing and supporting the fractured natural human bones/joints. Under some condition, negative reaction like release of ions from the bare metal toward the human body fluid leads to corrosion. In this proposed research paper, the biocompatibility of the laser surface-modified austenitic stainless steel (SS316L) and nickel-based superalloy (Inconel 718) was studied. The investigation on laser-modified surfaces is evaluated through electrochemical polarization analysis using simulated body fluid (SBF). The samples subjected to electrochemical polarization analysis were characterized by optical image analysis, SEM, EDS, and XRD analysis. It was inferred that laser surface-modified materials provided enhanced corrosion resistance and bare nickel alloy is more susceptible to corrosion by SBF.

Background. The Basic Package of Health Services (BPHS) program has increased access to immunization services for children living in rural Afghanistan. However, multiple surveys have indicated persistent immunization coverage gaps. Hence, to identify gaps in implementation, an assessment of the BPHS program was undertaken, with specific focus on the routine immunization (RI) component. Methods. A cross-sectional survey was conducted in 2014 on a representative sample drawn from a sampling frame of 1858 BPHS health facilities. Basic descriptive analysis was performed, capturing general characteristics of survey respondents and assessing specific RI components, and χ2 tests were used to evaluate possible differences in service delivery by type of health facility. Results. Of 447 survey respondents, 27% were health subcenters (HSCs), 30% were basic health centers, 32% were comprehensive health centers, and 12% were district hospitals. Eighty-seven percent of all respondents offered RI services, though only 61% of HSCs did so. Compared with other facility types, HSCs were less likely to have adequate stock of vaccines, essential cold-chain equipment, or proper documentation of vaccination activities. Conclusions. There is an urgent need to address manpower and infrastructural deficits in RI service delivery through the BPHS program, especially at the HSC level.

In current research, the engineering materials are trending towards biomedical applications. One of the main focuses is on selection of appropriate manufacturing techniques, surface behavior under body fluid and cell viability analysis on titanium-based implant material. Commercially available titanium implants are used to machine with electrospark erosion method. The experiments are planed based on varying the input parameters such as pulse on/off time and applied voltage for better surface quality. Their surface quality is evaluated in terms of average roughness and surface profile. The sample machined at 50 V and 5 µs (applied voltage and pulse on time) has been observed to have good quality surface when compared to other process conditions. The influence of voltage and pulse on time has more significance to achieve better surface quality. Due to the formation of oxide, micropore and microcracks, the biocompatibility has to be decreased. Subsequently, the simulated body fluid (SBF) developed using chemical reagents is used to study the electrochemical behavior. Further the machined surface and SBF exposed surface are analyzed with electron imaging techniques and spectra analysis. Methyl Tetrazolium (MTT) assay and the cell viability investigations were also performed on the machined surface. The cell adherence, rate of growth and its viability were evaluated for 24 h. The output response based on mechanical, metallurgical and biocompatibility of the implant has been considered for current discussion. Maximum roughness produced due to surface oxidation during machining has produced less corrosion rate. From the studies, it is clear to notice that the cell cultured over the machined surface has increased proliferation constantly and found suitable for future investigation.

Additive manufacturing and its process involved during manufacturing of engineering components are thriving areas in current researches. The usage of Direct Metal Laser Sintering (DMLS) process, can resolve the difficulties involved in the manufacturing of components used with turbine engines. The commercially available alloy Incone1718 is compatible with DMLS based Su-718 material. This investigation examines and experiments the effect of heat treatment process, using a combination of solutionizing at 1100 °C (2h) and aging at 845 °C for 24h, followed by air cooling. The metallurgical changes were observed with the help of optical imaging, to perceive the phase/structural transformation. Further, the heat treated samples were subjected to electrochemical polarization studies with 1.0 M H2SO4 as an electrolyte. The influence of alloying elements, before and after the heat treatment process of samples were analysed through scanning electron microscope and energy dispersive spectroscopy. The experimental results prove that, corrosion resistance was found to be much better while following the sequence of DMLS HT > Bare DMLS > Bare Commercial > Commercial HT alloy. However, the heat treated DMLS sample obtained during experimentation had lower current density and more positive corrosion potential than the commercial alloys.

OBJECTIVES:To evaluate the prevalence and severity of TMDs in house officers and postgraduate students belonging to public and private sector medical and dental colleges.METHODOLOGY:This was a cross sectional study carried out from July 2018 to September 2018 in Department of Oral and Maxillofacial Surgery, Sardar Begum Dental College and Hospital, Peshawar. After approval from ethical committee Gandhara University, an informed consent was obtained and Fonseca questionnaire was used to evaluate TMDs from 320 subjects who voluntarily want to participate in the study; selected with equal genders from public and private sectors medical and dental hospitals, Peshawar. Those who have musculoskeletal, neurological, systemic problems and orthodontics treatment subjects were excluded from the study.RESULTS:The age range selected was 22-32 years and the mean age presentation was 26.5 ± 3.4 years. Results showed that female postgraduate residents of private sector consider themselves tenser (18.8%) than others. 70.17% female house officers of private sector have noticed TMJ clicking and 83.17% of male house officers clenched or grind their teeth than others.CONCLUSION:The study concluded that mild and moderate TMDs are more common in-house officers and postgraduate residents.KEYWORDS: Temporomandibular Disorders, Prevalence, Temporomandibular Joint, Fonseca’s Anamnestic Index, Cross-Sectional Study

Background Hemangiomas are the most common vertebral body tumors typically discovered as incidental findings on spinal imaging. In 1% of patients, hemangiomas can be symptomatic causing persistent back pain that necessitate treatment. Percutaneous alcohol embolization (PAE) is an effective but challenging way of treating these lesions. We hereby report a case of vertebral hemangioma treated with PAE with unique technique. Methods 59-year-old man with chronic back pain refractory to medications, physical therapy and chiropractic maneuvers presented to our clinic. His MRI spine revealed multiple vertebral hemangiomas, most prominent at T8 and T10. On examination, the point of maximum tenderness was at T10. Limited spinal angiogram revealed tumor blush at the sites of vertebral hemangiomas. Under sterile conditions, two 10-gauge needles were advanced in the T10 vertebral body via transpedicular approach. The contrast injection revealed tumor blush and venous outflow into the azygous system. For PAE, we formed columns of contrast-absolute ethanol-contrast to avoid alcohol dilution and for adequate visualization during embolization. (figure 1) A bubble trapped between these columns, initially inadvertently and later intentional, also helped to keep the columns separate. The mixing of contrast to absolute ethanol is an alternative to this technique. However, it could decrease the efficacy of absolute ethanol in obliteration of hemangioma. Patient tolerated the procedure very well and endorsed clinical improvement on day 1. Conclusion During PAE for vertebral hemangiomas, formation of columns of contrast and absolute ethanol during embolization is an effective technique. It helps to preserve higher alcohol concentration and in turn, efficacy of embolization while maintaining adequate visualization. Disclosures S. Male: None. T. Mehta: None. A. Khan: None. A. Grande: None. R. Tummala: None. B. Jagadeesan: None.

Obesity is associated with alterations in brain structure and cognitive impairment. The mechanisms underlying obesity related decline in cognitive function are not well understood. Obesity related chronic systemic inflammation is postulated to be one of the potential mechanisms leading to cognitive dysfunction. It is unknown whether inflammation impacts brain areas important for higher level cognition such as the anterior cingulate cortex (ACC). Elevated myo-inositol (Ins), as measured by magnetic resonance spectroscopy (MRS), may be a marker of neuroinflammation and reflects activated astrocytes and microglia. We hypothesized that obese subjects (OB) will have higher ACC Ins compared to normal weight controls (CON) and that higher Ins will be associated with elevated blood inflammatory markers and reduced cognitive performance. We examined neurochemical profile from a 24x24x12mm3 voxel over the ACC using 1H MRS at 3 and 7 Tesla (T), in 5 nondiabetic OB (age 33 ± 5 years, BMI 43 ± 6 kg/m2) and 4 CON (age 36 ± 3 years, BMI 23 ± 3 kg/m2). Subjects also underwent cognitive testing and measurement of blood inflammatory markers. MR spectra were quantified using LCModel and the concentrations are expressed as a ratio to total creatine (tCr). There was a strong trend of higher Ins/tCr in ACC in OB compared to CON both at 3T (0.96 ± 0.06 vs. 0.88 ± 0.05, p =0.07) and 7T (0.91 ± 0.07 vs. 0.83 ± 0.08, p =0.17). Pearson correlations were used to test the relationship between Ins/tCr and markers of inflammation among all subjects. Higher blood inflammatory markers were associated with higher Ins/tCr (3T) in ACC (CRP, r=.74, p= 0.04; TNF α, r=.89, p=0.003) and with low levels of crystallized ability as measured by the NIH Toolbox Cognition Battery (CRP, r=-.73, p=0.03). Higher ACC Ins/tCr was also associated with poorer performance on a measure of fine motor coordination (r=.93, p=0.001). These data support the hypothesis that inflammation may contribute to the pathogenesis of brain and cognitive alterations in obesity. Disclosure A. Khan: None. J.M. Joers: None. M. Luciana: None. N. Rubin: None. Y. Siddiqui: None. S. Mangia: None. L.E. Eberly: None. S. Ikramuddin: Research Support; Self; Medtronic. E.R. Seaquist: Advisory Panel; Self; Eli Lilly and Company, Zucara Therapeutics Inc. Consultant; Self; 360 Consulting, MannKind Corporation. Research Support; Self; Eli Lilly and Company, JDRF, National Institutes of Health. Other Relationship; Self; American Diabetes Association, Sanofi, WebMD. G. Oz: None. A. Moheet: None. Funding National Institutes of Health

Woven EndoBridge (WEB) is an intrasaccular flow-disrupting device that has recently been approved by the U.S. Food and Drug Administration (FDA) for treatment of wide-neck ruptured and unruptured aneurysms at arterial bifurcations. Successful and effective treatment of aneurysms with the WEB device requires accurate sizing. For optimal positioning of the WEB device within the aneurysm sac, the diameter of the device has to exceed by the mean diameter of the aneurysm by 1.0 mm. However, this predictably results in an increase in the height of the device. In shallow, wide-necked aneurysms, this increase in height of the WEB device could result in encroachment of the device on the parent artery or branch vessel origins. In these circumstances, the placement of an intracranial stent can prevent such encroachment. In this video, we demonstrate the operative technique of stent-assisted WEB device placement that was performed at our institution for the treatment of a recurrent basilar apex aneurysm (Video 1). This previously ruptured aneurysm had been treated initially with primary coil embolization, and the patient consented to endovascular treatment of her aneurysm recurrence. The video illustrates this procedure using a combination of fluoroscopic images, fluoroscopic cines, and digital subtraction angiograms.

Abrasive water jet (AWJ) cutting is one of the advanced machining techniques to solve the different issues raised in the manufacturing process. Machinability of the material, surface damage, profile cutting, micro-/macro-product making, production time and cost are some of the problems caused. Research on AWJ has addressed the major problems to produce engineering components under the eco-friendly environment. It is a short report on AWJ cutting which is used to explain the basic problems and the principle while machining different engineering materials. In this paper, the influence of input process parameters, erodent/abrasive materials and bulk material properties along response on kerf wall inclination, material removal rate and surface quality are discussed in detail. In addition, the electron microscopic images are used to discuss the wear mechanism on different materials. The information discussed in the paper will support young researchers to understand the AWJ process and its scope.

Challenge has been taken to develop nickel – based superalloy SU718 through additive manufacturing process. The novelty of this research is to develop the SU718 alloy through direct metal laser sintering (DMLS) process for investigation. In this technique, powder bed is exposed to the laser energy to sinter and build the formation of alloy. Thus, formed alloys are not in isentropic structure and vary with dendrite morphology. In order to explore the behavior of alloying elements and to concurrently increase the mechanical properties, as-built alloys were heat-treated at different combinations with a plan of solutionizing, annealing and aging process. The dendritic structure from the as-built alloy was diffused through the HT plan to form austenitic structures. The mechanical properties and metallurgical qualities of the alloy were examined through different standard heat treatment (HT) cycles. The strengthening phase of γ’ and γ” was found to be increased after the solutionizing heat treatment process with a small amount of improvement in the δ phase. The mechanical properties of the as-built and HT SU718 alloys were evaluated. The evaluation results show the improvement in tensile strength and bulk hardness with less impact strength. Also, elongation of alloy was observed to be slightly higher in solutionizing than homogenization treatment.

This study is performed to assess the drilling of silicon carbide (SiC) and boron carbide (B4C) particles reinforced with 6351 aluminum matrix. Stir cast specimens were prepared using an electrical resistance furnace, and the mechanical properties were revealed. Experiments were carried out with varying spindle speed, feed rate, and point angle to analyze the drill tool temperature, thrust force, and surface roughness. Analysis of variance (ANOVA) was performed to determine the significance and the percent of influence of each input process parameter on the quality response. The results show that the increasing spindle speed reduces the thrust force and surface roughness, but increases the tool temperature. Furthermore, the point angle tool of 90° reduced the thrust force significantly but negatively influenced the other output responses. The spindle speed contributes more to the thrust force and surface roughness by 63.53% and 44.01%, respectively, and the point angle contributes 48.88% to the to...

In this paper, the sliding wear behaviour of nickel based superalloy pin was investigated on disc with two different coatings. The plasma sprayed NiCr–Cr2O3 coating and Al2O3+40%TiO2 (A40T) coating were used on the disc for wear studies. The sliding wear tests were performed on dry conditions at room temperature for a constant sliding velocity for two different applied loads (5 and 10 N). The mass loss, wear resistance and coefficient of friction between the pin and disc were studied during investigations. The wear mechanism involved in the NiCr–Cr2O3 coatings is three-body abrasion and Cr2O3 being the third body between pin and disc. The wear rate is high due to the applied load and suppressed cracks. In A40T coating, the minute debris collected on the surface of the coatings acts as a solid lubricant and reduces friction and wear rate. The SEM and energy dispersive spectroscopy analysis were also carried out for characterisation studies on pin after wear studies. The life of nickel pin on A40T coatings ...

Solid particle erosion has been considered as a major problem in all the engineering application. The present erosion studies on the influence of different parameters on erosion for duplex stainless steel (DSS2205) were carried using an air jet erosion test rig with 50 μm size alumina particles at room temperature. The effect of process parameters on erosion were studied using Taguchi method and the contribution was analyzed using ANOVA. The eroded surface was analyzed by Scanning Electron Microscope (SEM). Taguchi method was utilized to find the optimum process condition which produces lower erosion rate. The results concluded that the impingement angle had greater influence on erosion rate followed by flow velocity and discharge rate. The results were finally validated by the confirmatory experiment.

Laser cladding is one of the popular surface modification processes for providing enhanced wear and corrosion resistance to steels in various applications. In this article the investigations on laser cladding of Stellite 6 on EN8 steel has been reported. Stellite 6 is an extremely wear and corrosion resistant alloy and this study reports the corrosion behaviour of the cladded samples. Nine cladded samples were developed with the combination of different process parameters. Each sample was tested for corrosion behaviour using 1 M sulphuric acid solution. Metallurgic studies on the nine samples were conducted and the results have been reported. A clear correlation between the laser cladding parameters and the corrosion behaviour has been established.

Anthropogenic and climatic stressors have affected the forests of northern Pakistan in recent decades. Several studies have been conducted to understand forest growth and its relation to the changing climate in this region, but more work needs to be done to understand this complex environment. In this study, we have collected tree core samples of three conifer species (Pinus wallichiana, Picea smithiana, and Abies pindrow) from three different sites in northern Pakistan to understand their radial growth pattern with the goal of finding a relationship between ring-width and climatic parameters (temperature, precipitation, and drought). A 610-year (AD 1406–2015), a 538-year (AD 1478–2015), and a 306-year (AD 1710–2015) long tree-ring width chronology of Pinus wallichiana, Picea smithiana, and Abies pindrow were developed, respectively, using living trees. The ring-width chronologies of these three species showed a strong positive link with the self-calibrated Palmer Drought Severity Index (scPDSI) rather than precipitation or temperature alone, indicating that soil moisture is the primary limiting climatic factor for the growth of these species in the sampling locations. The chronologies of Pinus wallichiana and Picea smithiana exhibited growth suppressions during AD 1570–1610 and the second half of 17th century while their growth was heightened from AD 1540–1560. We have found the lowest growth in Abies pindrow and Picea smithiana from AD 1900–1920, suggesting dry conditions. All three chronologies have exhibited the most rapid increase in growth during the recent decades, suggesting that this region is experiencing climate change with a strong trend towards wetter conditions.

Epoxy decays its dielectric characteristics and exhibits degradation of main hydrocarbon on exposure to multiple environmental stresses. Inorganic oxides-based epoxy composites have been performingwell in many applications and short-term testing; therefore, evaluation of their dielectric and structural characteristics under extreme weathering conditions may also unleash enhancement in these characteristics. To explore dielectric properties and degradation of main hydrocarbon group, neat epoxy and silica-based epoxy microcomposite (15% micro-silica loading) and nanocomposites (5% nano-silica loading)have been prepared and subjected to acid rain, heat, ultra-violet radiation, salt fog, and humidity in a chamber that was specially fabricated in view ofservice conditions. Interesting results were obtained before and after aging. Enhanced intactness of methylene group was observed in nanocomposite followed by micro composite. Similarly, for epoxy nanocomposites not only higher dielectric constant, lower energy dissipation and conductivity was recorded before application of stresses, but also nanocomposite showed superior sustainability in these properties after aging. In all analyses, microcomposites performed better than neat epoxy but in conductivity the results of both samples were found comparable.

Introduction: Understanding the risk of aneurysmal subarachnoid hemorrhage in pregnant women with known history of Unruptured Intracranial Aneurysm (UICA) could potentially impact the delivery method. Due to presumed risk of intrapartum aneurysm rupture, understanding practice patterns of delivery methods and related complication risk is of importance. Methods: We used Nationwide Inpatient Sample database (1998-2014) to identify all the hospitalizations for childbirth in women with and without history of UICA. Patients with intracranial vascular malformation and traumatic intracranial hemorrhage were excluded. The cohort of pregnant women with known history of UICA was compared with the cohort of those without history of UICA with univariate analysis. Results: A total of 323 patients with known history of UICA were hospitalized for childbirth compared to 13,669,848 with no history of UICA. Higher rates of intracranial hemorrhage was observed in history of UICA group compared to no history of UICA [subarachnoid hemorrhage (0.31% Vs 0.001%, p Conclusion: Women undergoing childbirth with known history of UICA have higher risk of intracranial hemorrhage, peripartum complications, and longer hospitalizations compared to women without a known UICA. Aggressive management of risk factors for aneurysm rupture including hypertension and smoking could potentially decrease the rupture risk. Further research is needed to understand whether delivery method has an impact on decreasing risk of rupture.

Introduction: The treatment of choice for Unruptured intracranial aneurysms (UICA) is dependent on assessment of several factors including aneurysm size, location, and morphology, along with patient's life expectancy and comorbid conditions. Although multiple studies have deliberated upon the efficacy of surgical and endovascular aneurysm treatment for UICA, the rate of readmission with either technique has not been specifically studied. Methods: We used the Nationwide Readmission database to assess the readmission trends related to various treatment approaches for UICA. The treatment approaches were subdivided into four groups; surgical clipping group and three endovascular approach groups (coil embolization, stent assisted coil embolization and only stent placement groups). All four groups were compared for the characteristics of index hospitalizations and top causes of readmissions. Results: We identified 3533 patients treated with clipping and 4134 (3865 coil embolization, 192 only stent placement and 76 stent assisted coil embolization) patients treated with endovascular approach. Thirty day readmission rate (30RR) was significantly higher with surgical clipping compared to the three endovascular approach groups (8.37% Vs 4.77%, p Conclusion: Patients undergoing endovascular treatment for UICA are less likely to be readmitted and more likely to be discharged home compared to surgical clipping. Given the complex decision making with consideration of anatomic and patient factors for UICA treatment, these findings do not necessarily prove the general superiority of the endovascular approach but do suggest that when a UICA can be safely treated with either technique, the endovascular approach might reduce the chances of readmission.

In this paper, the Optimal Homotopy Asymptotic Method is extended to derive the approximate solutions of fractional order two-dimensional partial differential equations. The fractional order Zakharov–Kuznetsov equation is solved as a test example, while the time fractional derivatives are described in the Caputo sense. The solutions of the problem are computed in the form of rapidly convergent series with easily calculable components using Mathematica. Reliability of the proposed method is given by comparison with other methods in the literature. The obtained results showed that the method is powerful and efficient for determination of solution of higher-dimensional fractional order partial differential equations.