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To meet the demands of the manufacturing industry, a more robust approach is needed for current manufacturing processes. Machining of very hard materials with excellent dimensional accuracy and surface integrity is a challenging task, Currently, the electrical discharge machining (EDM) process is the optimal solution for machining such materials. Electrical discharge drilling machines find applications in various sectors such as aerospace, automobile and medicine. In this research, two different brass electrode geometries are considered: tubular electrode tool (TET) and double D tubular electrode tool (DDTET) on an SS202 work-piece. The input parameters of peak current (PI), pulse time ON (PONT), and pulse time OFF (POFFT) were varied. The output response measured and compared were material removal rate (MRR) and over cut (OC). The Taguchi technique was used to design the l16 orthogonal array (OA) experiment, and analysis of variance (ANOVA) was employed for result analysis using Minitab20 statistical software package. The results showed that the DDTET method produced significantly better MRR and OC improvements of 21.66 % and 2.28 % respectively. Additionally, a study was conducted on the formation of the recast layer (RL) and the heat affected zone (HAZ). [ABSTRACT FROM AUTHOR]

The present work involves in a novel approach of studying the material characteristics of AZ31 alloy by varying the cooling method in powder metallurgy and particle size of the matrix material. It also has a novel approach of reinforcing AZ31 alloy with quarry dust and providing self oxide coating to the material in a distinct way for corrosion resistance. The alloy is prepared through powder metallurgy with a pressure of 675 MPa, sintered at 540 ºC, with one hour of soaking. The Scanning Electron Microscopy images are taken to analyse the microstructure. Wear and corrosion studies are done to analyse the effect of parameters. Optimisation for wear is also done with Taguchi method. The AZ31 samples reinforced 5, 10 and 15% of quarry dust are prepared and studied for mechanical properties. The material prepared using 75–150 micron range, cooled in still air cooling and with 5% reinforcement has shown higher values of compressive strength and microhardness. The alloy provided with self-oxide coating has shown higher resistance to corrosion than that of uncoated alloy and the composite. [ABSTRACT FROM AUTHOR]

Thermally induced stresses can build up in rigid pavements without pressure relief joints. The pressure created becomes a problem for adjacent structures such as bridges. The pressure can cause the pavement to push on the bridge and close the bridge expansion joints. This sets the stage for additional distress if not repaired quickly. This paper presents a case study where excessive pavement pressure damaged a two-span conventional bridge spanning Interstate 35 in Moore, Oklahoma. The bridge was instrumented with vibrating wire sensors to gather information on the behavior of the bridge before and after the repairs. There is a dearth of sensor verified observations of excessive pavement pressure acting on conventional bridges. The sensor data provided in-depth information on the response of the distressed bridge before and after repairs to thermal loading. Prior to the repairs the approach pavement was pushing on the bridge deck and causing the abutment backwalls to tilt toward the bridge. Following the repairs, the approach pavement is no longer pushing on the bridge deck. However, the abutment backwall is now moving in response to thermal changes in the bridge deck, likely due to excessive friction between the deck and the abutment backwall. U-shaped shaped cracking and spalling, previously observed in integral abutment bridges, was observed at this conventional abutment bridge, and the mechanisms causing these cracks and spalling are discussed. Through this study it was found that placement of pavement pressure relief joints relative to the bridge is crucial for reducing the magnitude of stress acting on the bridge. It was also found that the pavement stress acting on a bridge deck can be estimated with vibrating wire strain gauges given a baseline strain response for the approach pavement. [ABSTRACT FROM AUTHOR]

This document is a closure to a previous article titled "Excessive Approach Pavement Pressure against Conventional Bridges." The closure addresses queries raised by a discusser. The first query clarifies that the photograph in question is not of the bridge deck, but rather the juncture between the approach slab and the approach roadway. The second query explains that the bridge was not designed to accommodate thermal expansion from the approach roadway, which caused the bridge deck to be shoved over the backwall. The third query discusses the occurrence of U-shaped cracking on the abutment backwall, hypothesizing that friction and reinforcing steel are causing this phenomenon. The fourth query clarifies the placement of the 2016 pavement pressure relief joint. The writers express gratitude to the discusser for their insights and acknowledge the support of the Oklahoma Department of Transportation and the Federal Highway Administration. [Extracted from the article]

This work aims to optimize the machining parameters and study the effect of powder-mixed dielectric fluid on the electrical discharge machining (EDM) process. The TOPSIS method of optimization is adopted to identify the optimal machining parameters. HCHCr die steel is preferred as a machining material. Due to their hard and ductile nature, Ni, Zr, and Ni+Zr were selected as powder inclusion in dielectric fluid. An L9 array Taguchi DOE is preferred to perform the experiments with parameters like peak off time, pulse off time, and pulse current. TOPSIS study revealed that the third level of powder dielectric fluid (Ni+Zr), 7A peak current, 9 µs pulse on time, and 2 µs pulse off time were specified as the optimal condition. Pulse on time (Ton) significantly impacted metal removal rate and surface roughness while machining operation on HCHCr die steel. SEM analysis was done to find the effect of powder-mixed dielectric fluid, while EDAX analysis was done to ensure the presence of powder inclusion. [ABSTRACT FROM AUTHOR]

The synthesis of Magnesium based alloy AZ31 using Magnesia Packed Sintering (MPS), an innovative approach in powder metallurgy is focused here. It is aimed to exclude the usage of protective gases for preventing oxidation and to optimize the process parameters. This method uses magnesia powder packed around the green compact inside a steel container to avoid oxidation and burning. This approach of sintering is developed as an alternative method for atmospheric protection. This method can be applied to fabricate magnesium based alloys and composites. Taguchi method integrated with GRA is employed for parameter optimization. Experiments are conducted based on L9 orthogonal array to analyse the effect of compaction pressure(675,700,725MPa),sintering temperature(450,500,540°C)and holding time(60,90,120 minutes).The GRG of output responses like compressive strength, micro hardness is analysed using ANOVA. Micro structural analysis is done using Scanning Electron Microscopy (SEM). Tests of confirmation with optimized parameters shown improvement in strength and hardness.Energy Dispersive X- ray Spectroscopy analysis is carried out to confirm the presence of Al, Zn, Mn in the sintered compact to ensure AZ31 composition. The phase analysis is done using X-ray Diffraction(XRD). The results proved that the new process is effective. [ABSTRACT FROM AUTHOR]

Introduction: The Heliostar™ ablation system is a novel RF balloon ablation technology with an integrated three‐dimensional mapping system. Here, we describe our early experience and procedural outcomes using this technology for atrial fibrillation catheter ablation. Methods: We sought to comprehensively assess the first 60 consecutive patients undergoing pulmonary vein isolation using the novel HELISOTAR™ RF balloon technology including procedural outcomes. A comparison of the workflow between two different anaesthetic modalities (conscious sedation [CS] vs. general anaesthesia [GA]) was made. Procedural data were collected prospectively from two high‐volume centers (Barts Heart Centre, UK and University Hospital of Zurich, Zurich). A standardized approach for catheter ablation was employed. Results: A total of 35 patients had the procedure under CS and the remaining under GA. Mean procedural and fluoroscopy times were 84 ± 33 min and 1.1 min. The median duration of RF energy application was 7 (5–9.8) mins per patient. All veins were successfully isolated, and the median isolation time was 10 (7–15) seconds. Our cohort's rate of procedural complications was low, with no mortality within 30 days postprocedure. Conclusion: Our early experience shows that catheter ablation using the Heliostar™ technology can be performed efficiently and safely; however, long‐term data is yet to be established. Low fluoroscopy requirements, short learning curves and use of this technology with CS is possible, including the use of an oesophageal temperature probe. [ABSTRACT FROM AUTHOR]

Desires of materials with lesser weight made wide spread use of alloys based on magnesium in automobiles and aerospace applications in the view of overcoming lower strength of these materials when compared to aluminium, these materials are added with some hard materials like ceramics, metal oxides or natural remaining as a reinforcing phase with a proof for improvement in properties. In the present work AZ31 alloy is strengthened by adding Coconut Shell Ash particles (CSAp) by means of powder metallurgy and the examinations like microstructure, micro hardness, compressive strength and wear are conducted. The ash particles content as reinforcement has not imparted larger variation in the strength and hardness, the wear resistance is increased with the addition of ash particles and the addition of CSAp exceeding 3% leads to crack. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) paint with a hydrophobic surface can be easily fouled. In this study, hydrophilic silica nanoparticles and hydrophobic silane were used to modify the surface hydrophobicity that affects the fouling properties of PU paint. Blending silica nanoparticles followed by silane modification only resulted in a slight change in surface morphology and water contact angle. However, the fouling test using kaolinite slurry containing dye showed discouraging results when perfluorooctyltriethoxy silane was used to modify the PU coating blended with silica. The fouled area of this coating increased to 98.80%, compared to the unmodified PU coating, with a fouled area of 30.42%. Although the PU coating blended with silica nanoparticles did not show a significant change in surface morphology and water contact angle without silane modification, the fouled area was reduced to 3.37%. Surface chemistry could be the significant factor that affects the antifouling properties of PU coating. PU coatings were also coated with silica nanoparticles dispersed in different solvents using the dual-layer coating method. The surface roughness was significantly improved by spray-coated silica nanoparticles on PU coatings. The ethanol solvent increased the surface hydrophilicity significantly, and a water contact angle of 18.04° was attained. Both tetrahydrofuran (THF) and paint thinner allowed the adhesion of silica nanoparticles on PU coatings sufficiently, but the excellent solubility of PU in THF caused the embedment of silica nanoparticles. The surface roughness of the PU coating modified using silica nanoparticles in THF was lower than the PU coating modified using silica nanoparticles in paint thinner. The latter coating not only attained a superhydrophobic surface with a water contact angle of 152.71°, but also achieved an antifouling surface with a fouled area as low as 0.06%. [ABSTRACT FROM AUTHOR]

• Explored the facet dependent HER and OER activity of CoSn(OH) 6. • Revealed the role of Mn3+ ions on the morphological transition of CoSn(OH) 6. • The two-electrode system shows a cell potential of 1.60 V at 10 mA cm–2. • Achieved the maximum ECSA (400 cm2) and TOF (HER, 0.97 s-1 & OER, 38.4 s-1). In this study, we report morphologically dependent electrocatalytic oxygen and hydrogen evolution reactions in an alkaline medium. The bifunctional electrocatalyst such as cobalt tin hydroxide (CoSn(OH) 6) was prepared by hydrothermal method. Importantly, tuning the morphological variation of CoSn(OH) 6 into cubes, octa- and dodecahedra and their corresponding growth mechanisms are analyzed and explored the electrochemical studies. Among the different morphologies, the CoSn(OH) 6 dodecahedron (CTH-DH) displays a substantially enhanced overall electrocatalytic water splitting reaction. It is firmly due to the [Mn3+] and [CH 3 COO-] ions do enable the morphological progression of the CTH cubic crystals with more facets. The highly active catalytic sites on the facets of CTH-DH permit the adsorption of abundant OH groups during the hydrogen and oxygen evolution reactions. Moreover, in a two-electrode system, the CTH-DH ǁ CTH-DH electrolyzer exhibits a cell potential of 1.60 V at 10 mA cm–2 with a remarkable reliable long-term stability. In addition, the structural transformations of the as-prepared CoSn(OH) 6 crystals are monitored before and after electrocatalysis using TEM study. As a result, the study highlights the potential of Mn-containing CTH-DH facets as viable electrocatalysts in efficient H 2 production. [Display omitted] [ABSTRACT FROM AUTHOR]

Magnesium based alloys are some of the widely used light weight metals in vehicles and aerospace industries, but these materials are having low strength to weight ratio when compared to aluminium. To enhance their strength to weight ratio, some ceramic materials like carbides and oxides of metals are added as reinforcements. In this work, AZ31 magnesium alloy is reinforced with 1%, 2% and 3% of Groundnut Shell Ash particles (GSAp) through powder metallurgy. Micro hardness and compressive strength are studied and the microstructural analysis is also done. The addition of ash particles as reinforcement has not shown much variation in the strength and hardness. The addition of ash particles of more than 3% leads to crack. The addition of ash particles increases the rate of corrosion. [ABSTRACT FROM AUTHOR]

Several modes of bridge distress related to interactions with approach roadways have been observed in Oklahoma through routine maintenance inspections. Upon closer review it was found out that there are two main mechanisms for a category of distress that includes bearings tilting, anchor bolts bending or shearing, concrete slope walls cracking, and girders pushing against the backwall. One of these mechanisms is the lateral movement of approach embankments. This movement tends to happen early in the life of a bridge and pushes the abutment toward the bridge and closes the bridge expansion joints. The other mechanism is the pressure from rigid approach pavements due to closed or nonexisting joints on pavements. The pavement pressure exerted on the bridge deck also closes the expansion joints. This paper focuses on the lateral movements of approach embankments. As a part of this research an extensive instrumentation and monitoring program was undertaken on a five-span bridge in Ada, Oklahoma, showing the characteristic signs of this distress. Through review of routine inspection reports and analysis of recorded data from installed instruments; a rehabilitation plan was developed and implemented. Following the rehabilitation, the instruments were monitored for an additional 3.5 years to verify the repairs were successful. Through this research it was found that if lateral embankment movement is the mechanism of distress, a successful rehabilitation plan can be implemented once lateral movement has stopped. The rehabilitation involved installing new bridge expansion joints and changing some of the girder end conditions for the monitored bridge. As a result of this research the Oklahoma Department of Transportation expanded their bridge inspection protocol to identify these two mechanisms for this category of bridge distress. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiMo MOF electrodes deliver a remarkable 3811 Fg−1 capacitance (at 1 Ag−1) • NiMo MOF device retains 92.79% capacitance after 10,000 cycles. • Lights LEDs for 11 min, showcasing energy storage potential. • DFT reveals a narrow band gap for efficient charge storage. This work explores the potential of bimetallic nickel (Ni) molybdenum (Mo) metal–organic framework (MOF) (NiMo MOF) composites as promising electrode materials for high-performance energy storage. This study utilizes graphite sheet (GS) electrodes throughout, offering a cost-effective alternative to expensive metal foam or mesh electrodes. Herein, NiMo MOF were successfully synthesized using a facile hydrothermal method, exhibiting a rod-like morphology with a high surface area (1,100 m2 g−1) and both Ni and Mo in the MOF are nearly in equiproportional. In three electrode system, electrochemical studies revealed that NiMo MOF electrodes exhibit phenomenal specific capacitance (3811 Fg−1 at 1 Ag−1) compared to Mo MOF and Ni MOF electrodes. Importantly, the NiMo MOF||AC asymmetric pseudocapacitor device demonstrates a high specific capacitance of 666.21 Fg−1 at 1 Ag−1 with excellent cycling stability (92.79 % capacitance retention even after 10,000 cycles at 15 Ag−1). Moreover, the asymmetric device successfully powers an LED light for 11 min, showcasing its potential for practical applications. Further, the theoretical counterpart such as density functional theory (DFT) studies supports the experimental findings, suggesting a narrow band gap for NiMo MOF, indicative of its semi-metallic nature and favorable electrical conductivity for pseudocapacitor applications. Accordingly, the enhanced psuedocapacitance performance is attributed to the synergistic effect of Ni and Mo in the bimetallic MOF where the shallow band gap (0.002 eV) deliberates faster electron transfer kinetics and improved charge storage. These results build an avenue for developing MOF based materials as high-performance energy storage materials for futuristic applications. [ABSTRACT FROM AUTHOR]

Background: The risk factors for developing pacing induced left ventricular dysfunction (LVD) in patients with high burden of right ventricular pacing (RVP) is poorly understood. Therefore, in the present study, we aimed to assess the determinants of pacing induced LVD. Methods: Our data were retrospectively collected from 146 patients with RVP > 40% who underwent generator change (GC) or cardiac resynchronization therapy (CRT) upgrade between 2016 and 2019 who had left ventricular ejection fraction (EF) ≥50% at initial implant. Results: A total of 75 patients had CRT upgrade due to pacing induced LVD (EF < 50%) and 71 patients with preserved LV function (EF ≥ 50%) had a GC. Primary indication for pacing in both groups was complete heart block. Male predominance (p =.008), prior myocardial infarction (MI) (p =.001), atrial fibrillation (AF) (p =.009), chronic kidney disease (CKD) (p =.005), and borderline low systolic function (BLSF) (EF 50%–55%) (p =.04) were more prevalent in the CRT upgrade group. Presence of AF (odds ratio [OR] = 3.05, 95% confidence interval [CI] 1.42–6.58; p =.004), BLSF (OR = 3.8, 95% CI 1.22–11.8; p =.02), and male gender (OR = 2.41, 95% CI 1.14–5.08; p =.02) were independent predictors for RVP induced LVD. Age (OR = 1.08, 95% CI 1.02–1.14; p =.005) and BLSF (OR = 5.33, 95% CI 1.26–22.5; p =.023) were independent predictors of earlier development of LVD after implant. Conclusions: Our results suggested that AF, BLSF, and male gender are predictors for development of pacing induced LVD in patients with high RVP burden. LVD can occur at any time after pacemaker implant with BLSF and increasing age associated with earlier development of LVD. [ABSTRACT FROM AUTHOR]

The boiler efficiency is improved with the help of economizer it is one of the main accessory part in the boiler. Boiler feed water is preheated with the entry of reused flue gas through economizer. This present work is planned to analyse the overall heat flux and overall heat transfer in the boiler economizer. Higher amount of flue gases passing around the economizer to preheat the feed water at the same time much more heat is transferred. The heat transfer is analysed by statistical method with influence of different process parameters. Economizer fin dimensions are major consideration to taken for this analysis and estimate the overall heat flux and overall heat transfer. The process parameters of this study are named as thickness of the fin (3.5 mm, 4 mm, 4.5 mm, and 5 mm), height of the fin (4 mm, 5 mm, 6 mm, and 7 mm), fin gap (12 mm, 14 mm, 16 mm, and 18 mm, and tube diameter (44 mm, 46 mm, 48 mm, and 50 mm). The response values are finding as overall heat flux and overall heat transfer. [ABSTRACT FROM AUTHOR]

Background: Timing of hip fracture surgery for the internal fixation of an intracapsular fracture remains controversial and few studies to date have been able to determine the optimum time to surgery in minimizing osteonecrosis and non-union with intracapsular fractures after fixation.Methods: Using a local hip fracture database managed by the senior author over a 32 year period, those who underwent osteosynthesis following intracapsular fractures were assessed for risk of development of non-union and osteonecrosis. Multivariate regression analysis was performed focusing on factors that were predictive of complications. Patient demographics, time from injury to surgery, fixation method, fracture pattern and complications at one year were reported. The primary outcome was whether delay to surgery contributed to risk of complications, defined as non-union or osteonecrosis. Secondary outcomes assessed the contribution of other factors to these complications.Results: 2,366 patients were identified with an average age of 74.7 years and 66.5% were female. 1189 (50.3%) of fractures were displaced. 481 (20.3%) had a complication at one year following fixation. 78 (3.3%) were fixed by DHS, 6 (0.3%) by cephalomedullary nail, (1257) 53.1% by cannulated screws and 1025 (43.3%) by Targon® screw. Multivariate regression revealed no significant correlation between delay to surgery and complication rates (OR 0.99, 95% CI 0.99, 1.01, p = 0.55). Significant variables include female sex (OR 2.03, 95% CI 1.58, 2.62, p<0.0001), fracture displacement (OR 4.8, 95% CI 3.79, 6.14, p<0.0001), independent mobility (OR 0.64, 95% CI 0.47, 0.87, p = 0.004) and use of Targon® screws compared to parallel screws (OR 0.61, 95% CI 0.48, 0.76, p<0.0001).Conclusions: Our study demonstrates no relationship between timing of surgery for fixation of intracapsular fracture and complication rates. Female sex and fracture displacement increased risk of complications whereas independent mobility and use of Targon® screw device in comparison to parallel screws were protective against non-union but not avascular necrosis. [ABSTRACT FROM AUTHOR]

Nuclear pore complexes (NPCs) are embedded in the nuclear envelope and facilitate the exchange of macromolecules between the nucleus and cytoplasm in eukaryotic cells. The dysfunction of the NPC and nuclear transport plays a significant role in aging and the pathogenesis of various neurodegenerative diseases. Common features among these neurodegenerative diseases, including Parkinson's disease (PD), encompass mitochondrial dysfunction, oxidative stress and the accumulation of insoluble protein aggregates in specific brain regions. The susceptibility of dopaminergic neurons to mitochondrial stress underscores the pivotal role of mitochondria in PD progression. Disruptions in mitochondrial-nuclear communication are exacerbated by aging and α-synuclein-induced oxidative stress in PD. The precise mechanisms underlying mitochondrial impairment-induced neurodegeneration in PD are still unclear. Evidence suggests that perturbations in dopaminergic neuronal nuclei are linked to PD-related neurodegeneration. These perturbations involve structural damage to the nuclear envelope and mislocalization of pivotal transcription factors, potentially driven by oxidative stress or α-synuclein pathology. The presence of protein aggregates, pathogenic mutations, and ongoing oxidative stress can exacerbate the dysfunction of NPCs, yet this mechanism remains understudied in the context of oxidative stress-induced PD. This review summarizes the link between mitochondrial dysfunction and dopaminergic neurodegeneration and outlines the current evidence for nuclear envelope and nuclear transport abnormalities in PD, particularly in oxidative stress. We highlight the potential role of nuclear pore and nucleocytoplasmic transport dysfunction in PD and stress the importance of systematically investigating NPC components in PD. [ABSTRACT FROM AUTHOR]

Excessive exposure to manganese (Mn) increases the risk of chronic neurological diseases, including Parkinson's disease (PD) and other related Parkinsonisms. Aggregated α-synuclein (αSyn), a hallmark of PD, can spread to neighboring cells by exosomal release from neurons. We previously discovered that Mn enhances its spread, triggering neuroinflammatory and neurodegenerative processes. To better understand the Mn-induced release of exosomal αSyn, we examined the effect of Mn on endosomal trafficking and misfolded protein degradation. Exposing MN9D dopaminergic neuronal cells stably expressing human wild-type (WT) αSyn to 300 μM Mn for 24 h significantly suppressed protein and mRNA expression of Rab11a, thereby downregulating endosomal recycling, forcing late endosomes to mature into multivesicular bodies (MVBs). Ectopic expression of WT Rab11a significantly mitigated exosome release, whereas ectopic mutant Rab11a (S25N) increased it. Our in vitro and in vivo studies reveal that Mn exposure upregulated (1) mRNA and protein levels of endosomal Rab27a, which mediates the fusion of MVBs with the plasma membrane; and (2) expression of the autophagosomal markers Beclin-1 and p62, but downregulated the lysosomal marker LAMP2, thereby impairing autophagolysosome formation as confirmed by LysoTracker, cathepsin, and acridine orange assays. Our novel findings demonstrate that Mn promotes the exosomal release of misfolded αSyn by impairing endosomal trafficking and protein degradation. [ABSTRACT FROM AUTHOR]

Several ground improvement techniques, which have been proven to be effective and economical solutions for increasing the lateral stiffness and strength of weak soils around piles, can often result in unnecessarily conservative large volumes of soil improvement. Additionally, there are no rigorous techniques available to analyze the seismic behavior of piles in improved soils that can be utilized in day-to-day engineering practice. In this study, a stand-alone one-dimensional finite element computer code called DYPAC (Dynamic Piles Analysis Code), which uses the beams on nonlinear Winkler foundation (BNWF) approach, was developed to analyze the seismic response of a single pile in both improved and unimproved soils. The computer code models the pile as a beam element and the nonlinear soil behavior as springs and viscous dashpots using a nonlinear p-y element, where y = displacement; and p = soil reaction per unit length of the pile. This study proposes and validates a method for modifying the p-y curves to consider the limited lateral extent of ground improvement. The p-y curves were inputted into DYPAC to analyze a series of dynamic centrifuge tests of single piles in soft clay improved using cement deep soil mixing (CDSM). Free-field site response analyses were performed using the DEEPSOIL computer program and the soil displacement-time histories were inputted into the free-field ends of the nonlinear p-y elements. The predictions made by DYPAC were validated using the centrifuge data and the results show that the DYPAC predictions are reasonable. Furthermore, the proposed method for modifying p-y curves to characterize CDSM-improved soil appears to be appropriate and practical. Moreover, the benefits of nonlinear DEEPSOIL free-field site response analyses during large earthquakes, as compared to equivalent linear analyses, were also demonstrated. [ABSTRACT FROM AUTHOR]

Background: Corona virus disease 2019 (COVID-19) contributes to cardiovascular complications including arrhythmias due to high inflammatory surge. Nevertheless, the common types of arrhythmia amongst severe COVID-19 is not well described. New onset atrial fibrillation(NOAF) is frequently seen in critically ill patients and therefore we aim to assess the incidence of NOAF in severe COVID -19 and its association with prognosis. Methods: This is a retrospective multicentre study including 109 consecutive patients admitted to intensive care units (ICU) with confirmed COVID-19 pneumonia and definitive outcome (death or discharge). The study period was between 11th March and 5th May 2020. Results: Median age of our population was 59 years (IQR 53-65) and 83% were men. Nearly three-fourth of the population had two or more comorbidities. 14.6% developed NOAF during ICU stay with increased risk amongst older age and with underlying chronic heart failure and chronic kidney disease. NOAF developed earlier during the course of severe COVID-19 infection amongst non-survivors than those survived the illness and strongly associated with increased in-hospital death (OR 5.4; 95% CI 1.7-17; p=0.004). Conclusion: In our cohort with severe COVID-19, the incidence of new onset atrial fibrillation is comparatively lower than patients treated in ICU with severe sepsis in general. Presence of NOAF has shown to be a poor prognostic marker in this disease entity. [ABSTRACT FROM AUTHOR]

Tranexamic acid (TXA) is a cheap and powerful drug that has several uses in surgery and is well established in elective orthopaedic surgery. At present, limited small studies have looked into its role in the acute hip fracture. Transfusion in the geriatric population presents risks and increased costs to healthcare systems around the world. Our retrospective study looks at the role of TXA administration at induction for both intracapsular fracture requiring hemiarthroplasty and our preferred method of fixation of extracapsular fracture by intramedullary nail (IM nail). We show a statistically significant reduction in the number of patients requiring transfusion as well as mean haemoglobin (Hb) drop in those undergoing hemiarthroplasty. This was not replicated in those undergoing IM nail fixation. Both groups showed no increase in 1-year mortality or thromboembolic events following TXA administration. These results support the use of TXA for hemiarthroplasty for intracapsular hip fractures over the age of 60.Objectives: The aim of this pre and post interventional study looks at the effects of intravenous administration of tranexamic acid on induction for elderly patients undergoing hemiarthroplasty or intramedullary nail fixation for hip fractures.Design: Pre and post interventional, randomised observational study SETTING: Large hip fracture unit, Level 2 Trauma Centre, single centre PATIENTS: Two arms of the study looking at those aged above the age of 60 undergoing hemiarthroplasty and intramedullary nail fixation without and with tranexamic acid on induction.Results: 12.1% of hemiarthroplasties required post-operative transfusion without tranexamic acid compared to 2.6% of those with tranexamic acid (n=15 vs n=3 respectively, p=0.006). Equally, the mean Hb drop in g/L is reduced in those with tranexamic acid compared to those without (mean Hb = 14.6 vs 17.7 respectively, p=0.034). This was not replicated in the IM nail group between those without and those with tranexamic acid (n=31 vs n=20 respectively, p= 0.16). The mean Hb drop in g/L was not statistically significant in the tranexamic acid arm compared to without (mean Hb = 19.2 vs mean Hb = 21.9, p=0.11). Gross reporting of thromboembolic events did not demonstrate an increase in the number of those with DVT, PE, MI or stroke. 1-year mortality was not statistically significant in either hemiarthroplasty or IM nail fixation following tranexamic acid administration.Conclusions: Tranexamic acid both statistically significantly reduces the number of patients requiring transfusion post hemiarthroplasty and also the value of mean Hb drop without appearing to increase in thromboembolic events or 1 year mortality rates. This does not appear to be emulated in the IM nail fixation although both thrombotic events and 1-year mortality rates are also not affected by administration of TXA. We propose that TXA has a role in hemiarthroplasty surgery in reducing post-operative transfusions.Level Of Evidence: Level 3 - retrospective cohort study. [ABSTRACT FROM AUTHOR]

With the increased incidence of neurodegenerative diseases worldwide, Parkinson's disease (PD) represents the second-most common neurodegenerative disease. PD is a progressive multisystem neurodegenerative disorder characterized by a marked loss of nigrostriatal dopaminergic neurons and the formation of Lewy pathology in diverse brain regions. Although the mechanisms underlying dopaminergic neurodegeneration remain poorly characterized, data from animal models and postmortem studies have revealed that heightened inflammatory responses mediated via microglial and astroglial activation and the resultant release of proinflammatory factors may act as silent drivers of neurodegeneration. In recent years, numerous studies have demonstrated a positive association between the exposure to environmental neurotoxicants and the etiology of PD. Although it is unclear whether neuroinflammation drives pesticide-induced neurodegeneration, emerging evidence suggests that the failure to dampen neuroinflammatory mechanisms may account for the increased vulnerability to pesticide neurotoxicity. Furthermore, recent studies provide additional evidence that shifts the focus from a neuron-centric view to glial-associated neurodegeneration following pesticide exposure. In this review, we propose to summarize briefly the possible factors that regulate neuroinflammatory processes during environmental neurotoxicant exposure with a focus on the potential roles of mitochondria-driven redox mechanisms. In this context, a critical discussion of the data obtained from experimental research and possible epidemiological studies is included. Finally, we hope to provide insights on the pivotal role of exosome-mediated intercellular transmission of aggregated proteins in microglial activation response and the resultant dopaminergic neurodegeneration after exposure to pesticides. Collectively, an improved understanding of glia-mediated neuroinflammatory signaling might provide novel insights into the mechanisms that contribute to neurodegeneration induced by environmental neurotoxicant exposure. [ABSTRACT FROM AUTHOR]

Cycling has gained in popularity as a recreational activity and method or travel, in part due to its recognised health benefits in maintenance of good cardiovascular strength and also for environmental issues. As a consequence of this, there is unfortunately an increased number of cycling related injuries. One particular injury incurred is a proximal femoral fracture, but there is little information in the literature with regarding this and its management. This retrospective, single centre, observation study looks at the number of cycling injuries over a six-year period in those under the age of 80. 50 patients were identified at an occurrence of 4.5% of the hip fracture population. The majority were male (n=37, 74%) with an average age of 60. Operative treatment was used for 48 (96%) patients with the majority being treated with internal fixation (n=42, 84%) and arthroplasty for the remainder. Average hospital stay was 5.6 days. One patient continued to complain of pain and subsequently underwent a total hip arthroplasty. The mean follow up for these patients was 1033 days (range 1 year to 7 years). 47 (94%) had full return back to pre-injury levels. Given that cycling is likely to increase in the future, we recommend that early surgical fixation is a viable and functionally positive treatment management in these particular group of patients.Objectives: The aim of this retrospective observational study over a six-year period was to assess the incidence of hip fractures in those under the age of 80 following a cycling related injury, the definitive management and primary index surgery opted and to report the radiological and functional outcome of these patients with at least 1 year of follow up.Design: Retrospective, observational study SETTING: Large hip fracture unit, Level 2 Trauma Centre, single centre.Patients: Patients under the age of 80 who sustained a proximal femoral fracture secondary to a fall and not attributable to pathological processes (namely malignancy and Paget's) were identified and followed up after 1 year.Results: 50 patients were identified over a six-year period of which 74% (n=37) were male and the remaining were female. 48 of these patients subsequently went on for operative management. Two patients presented late (7 days and 42 days from surgery) and were treated conservatively. The average hospital stay for these patients was 5.6 days, with index surgery occurring on average within 22 hours of admission. Mean follow up was 1033 days (range 1 year to 7 years) in all patients. Radiological union had occurred in all patients. One patient showed evidence of avascular necrosis but was asymptomatic. All but three patients had achieved the same level of mobility as pre-injury levels. All patients had the same level of social dependency. One patient continued to complain of pain and subsequently underwent a total hip arthroplasty.Conclusions: We demonstrate that the majority of our patients undergo surgical fixation and demonstrate good functional and radiological outcomes at a mean follow up of 1033 days. This is likely as a result of good pre-morbid status in these patients and good bone stock at index intervention. This study is one of the first to show this within the literature in this cohort of elderly patients. The number of cycling related injuries in the elderly population is likely to increase and our recommendation is that early surgical fixation provides good functional outcome in this subset of patients. [ABSTRACT FROM AUTHOR]

Introduction: Cryoballoon ablation is an established technique to achieve pulmonary vein isolation in patients with atrial fibrillation (AF). Recently, a new manufacturer of cryoballoon achieved regulatory CE marking (POLARx™; Boston Scientific). We describe our early experience of using this new market entrant of the technology and describe procedural aspects in comparison to the incumbent Medtronic Arctic Front Advance™. Methods: We assessed the first 40 AF ablations performed with the POLARx catheter at the Barts Heart Centre. These patients were compared with a contemporaneous series of patients undergoing ablation by the same operators using the Arctic Front Advance. Procedural metrics were prospectively recorded. Results: A total of four operators undertook 40 cases using the POLARx catheter, compared with 40 cases using the Arctic Front Advance. Procedure times (60.0 vs. 60.0 min) were similar between the two technologies, however left atrial dwell time (35.0 vs 39.0 min) and fluoroscopy times (3.3 vs. 5.2 min) were higher with the POLARx. Measured nadir and isolation balloon temperatures were significantly lower with POLARx. Almost all veins were isolated with a median freezing time of 16.0 (POLARx) versus 15.0 (Arctic Front Advance) min. The rate of procedural complications was low in both groups. Conclusion: The POLARx cryoballoon is effective for pulmonary vein isolation. Measured isolation and nadir temperatures are lower compared with the predicate Arctic Front Advance catheter. The technology appears similar in acute efficacy and has a short learning curve, but formal dosing studies may be required to prove equivalence of efficacy. [ABSTRACT FROM AUTHOR]

This paper demonstrates the study of performance, combustion and emission characteristics of a common rail diesel injection (CRDI) engine with the influence of exhaust gas recirculation (EGR) (5, 15 and 25%) at various fuel injection pressures (400, 500 and 600 bar) under the effective load conditions (0, 25, 50, 75 and 100%). The experiments were carried out in a controlled manner using the CRDI engine fuelled with 80% (D80) diesel (98% purity) blended with 20% (B20) tallow biodiesel. The engine has been operated at a rated speed of 1500 rpm on all load conditions, fuel injection timings of 10°, 15° and 20° bTDC, fuel injection pressures of 400, 500 and 600 bar, respectively. Combustion-influenced performance characteristics such as variation of in-cylinder pressure and net heat release rate in J deg−1 are also studied with the above operating conditions. It was observed that the usage of 20% biofuel blend shows considerable improvement in combustion, and it further enhances with an increase in the injection pressures. Besides, EGR (up to 25%) reduced significant pollutants at higher operating pressures (600 bar) at higher load conditions. It was also observed that CO2 emission increased with increase in the % EGR with an increase in the load conditions. However, for CO emission increased up to 50% load condition and subsequently tends to decrease due to improved combustion at higher load; hence higher temperature. NOx, smoke opacity continue to increase with the increase in pressure and the percentage increase in EGR due to its attainment of adiabatic temperature, which leads to the pathway for the Zeldovich mechanism. The present work shows light on the usage of tallow methyl ester produced from the wastes in the tannery industry as alternate biofuel operating the CRDI engines without compromising its combustion and emission characteristics to deliver the same power as petro-diesel. [ABSTRACT FROM AUTHOR]

Extreme variations in weather patterns have become increasingly common across the Southern Great Plains of the United States. The soil layer in the active zone above the groundwater table is often subjected to moisture variations due to seasonal weather changes that will influence the behavior of soils, including their strength and stiffness parameters. Designing a pile foundation in seismic-prone areas without considering the moisture changes in soil interacting with piles may adversely impact the seismic performance of the piles. The main aim of this study is to investigate the role of soil moisture conditions and suction caused by soil–atmospheric interactions on the dynamic behavior of the pile foundations interacting with clayey soils. This study uses a stand-alone finite element computer code called DYPAC (Dynamic Piles Analysis Code) developed using the Beams on Nonlinear Winkler Foundation (BNWF) approach. The influence of soil suction is incorporated into the p-y curves and free-field soil displacements using site response analyses by employing the concept of apparent cohesion. To perform nonlinear site response analyses, DEEPSOIL software V6.1 is utilized. The variation in soil suction with depth along the pile is considered using unsaturated seepage analysis performed by employing the commercial software PLAXIS LE Groundwater for three different clayey soils with plasticity ranging from low to medium to high. The analyses were performed using actual past daily recorded weather data for a testbed that experienced significant back-to-back flash droughts in 2022. This study found that extreme weather events like flash droughts can significantly affect the soil suction and seismic performance of the piles interacting with the unsaturated clayey soils. [ABSTRACT FROM AUTHOR]

Shear wave velocity is an important parameter for estimating soil properties used in analyzing the dynamic response of soil to seismic loading. This paper focuses on developing a model for predicting shear wave velocity in unsaturated soils. The model was developed primarily for the interpretation of seismic cone penetration tests (SCPTs) in unsaturated soil to account for seasonal variations in moisture conditions. In practice, SCPTs typically occur over a period of days without the option of choosing a wet or dry period. The question becomes, if tests are conducted during a dry period, how can shear wave velocity corresponding to a wetter period be predicted, or vice versa? Answering this question was the primary motivation of this work. The work involved field testing with the seismic cone penetrometer during wet and dry periods and a focused study at three sites involving comparison between field and laboratory testing for shear wave velocity. The model presented in this paper is built upon the significant work of many other researchers with reference to new experimental data obtained by the authors. It is demonstrated that a stress-based model incorporating matric suction can provide reasonable predictions of shear wave velocity and provides a method to interpret the impact of changing moisture content on shear wave velocities determined with SCPTs. [ABSTRACT FROM AUTHOR]

This paper presents a closure to "Influence of Lateral Movements of Approach Embankments on Bridges: A Case Study" by Kanthasamy K. Muraleetharan, Amirata Taghavi, Tommy D. Bounds, Gerald A. Miller, Bo Zhang, Walter L. Peters, and Royce W. Floyd. The authors agree that sensor-based construction monitoring is very beneficial to the performance of bridge embankments. Sensor-based construction monitoring of bridge embankments founded on soft soils could certainly help identify problems with embankment movement during and shortly after construction. [Extracted from the article]

Due to rise in drug resistance among pathogens, there is always an urge to look for new drug alternatives. So in this study we aimed to identify the unexplored rhizosphere microflora of alfalfa plant for new antimicrobials. With initial screening for isolates from rhizosphere region for antibacterial activity against selected bacterial pathogens, the isolate AL10 had better activity selected for this study. The isolate mass was cultured and secondary metabolites were extracted using ethyl acetate and subjected to FTIR and GC-MS analysis. Based on functional diversity analysis, the isolate subjected to anti-bacterial activity revealed significant activity against Streptococcus pneumonia, Klebsiella, S. aureus with zone of inhibition in the range of18-20 mm. Based on GC-MS analysis report ten compounds were identified and 1-Octadecane and 1-nonadecanol were found to be responsible for bio-activity. FT-IR results showed that N-H stretching functional group was dominantly present in the extract. Molecular identification of the isolate by 16S rRNA sequencing showed the isolate as Pantoea agglomerans. The results showed that the isolate P.agglomerans, gram negative bacteria had wide antibacterial activity due to 1- Octadecane and 1-nonadecanol. Though Alfalfa plant has been described for various biological activities, this is a first report on rhizosphere region of plant reporting for antibacterial potential microbes. [ABSTRACT FROM AUTHOR]

Prediction of unsaturated soil behavior during earthquake loading has received increasing attention in geotechnical engineering research and practice in recent years. Development of a fully coupled analysis procedure incorporating a coupled hydromechanical elastoplastic constitutive model for dynamic analysis of unsaturated soils has, however, been limited. This paper presents the implementation of a coupled hydromechanical elastoplastic constitutive model into a fully coupled dynamic analysis procedure and its validation using a centrifuge test. First, the fully coupled finite element equations governing the dynamic behavior of unsaturated soils with the solid skeleton displacement, pore water pressure, and pore air pressure as nodal unknowns are briefly presented. The closest point projection method is then utilized to implement the coupled hydromechanical elastoplastic constitutive model into the finite element equations. The constitutive model includes hysteresis in soil–water characteristic curves, cyclic elastoplasticity of the solid skeleton, and the coupling mechanisms between the SWCCs and the solid skeleton. Finally, the analysis procedure is validated using the results from a dynamic centrifuge test on an embankment constructed of compacted unsaturated silt subjected to base shaking. Reasonable comparisons between the predicted and measured accelerations, settlements, and deformed shapes are obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Data-driven approach to model biochar production from agricultural wastes. • SVM with quadratic kernel function outperforms fine Gaussian kernel function. • Exponential kernel function has most significant influence on GPR performance. • Levenberg-Marquardt and Scaled Conjugate Gradient trained ANN show superior performance. • Residence time and pyrolysis temperature significantly influence predicted biochar yield. Biochar is an important nanomaterial that can be used in wastewater treatment. The production of biochar is often done by heating biomass in the absence of oxygen, a process known as pyrolysis. The valorization process involves a complex chemical reaction which is often not easily demystified. The data obtained from the valorization of the biomass can be employed to model the process for the purpose of understanding the relationship between the input and targeted parameters thereby optimizing the process. This study employs a data-driven approach to model biochar production from agricultural wastes. The parametric analysis shows that the biochar yields obtained from the different agriculture wastes were significantly influenced by temperature, heating rate, residence time, and Nitrogen flow rate. The support vector machine (SVM) models with different kernel functions displayed predictive potentials of the biochar production with R2 in the range of 0.5–0.8. The Gaussian process regression models with different kernel functions offer better prediction potentials compared to the SVM models as indicated by a higher R2 > 0.7. The artificial neural network-based algorithms outperformed the SVM and GPR as indicated by the R2 > 0.9 and low predictive errors. The relative importance analysis shows that the residence time during the valorization reaction has the most significant influence on the predicted biochar produced from agricultural wastes. [ABSTRACT FROM AUTHOR]

The increased usage of digital platforms for communication and networking, particularly after the pandemic has caused concern about exposure to bullying and sexual harassment, particularly among young children and adolescents. Cyberbullying (CB) and cyber sexual harassment (CSH), although considered less harmful by many, may cause graver psychological manifestations than their physical forms, due to their potential for wider reach, easier access to private and sensitive information, ability to conceal perpetrator identity and continuous exposure of the victim to the harmful acts. Among the various characteristics, there were differences between age groups and gender, as well as varied psychological and behavioral features among victims and perpetrators which included low self-esteem, low academic performance and interestingly, some victims who themselves, later engage in perpetrating CB on others. The strategies for the prevention of CB and CSH are similar to that of the traditional forms, which predominantly include raising awareness among students, teachers and parents. This article reviews the characteristics of CB and CSH and discusses the limitations in existing laws and statutes in combating CB and CSH while highlighting the need for improving the policies and guidelines on CB and CSH among educational institutions and workplaces. [ABSTRACT FROM AUTHOR]

Alpha-synuclein seed amplification assays (αSyn-SAAs) have emerged as promising diagnostic tools for Parkinson's disease (PD) by detecting misfolded αSyn and amplifying the signal through cyclic shaking and resting in vitro. Recently, our group and others have shown that multiple biospecimens, including CSF, skin, and submandibular glands (SMGs), can be used to seed the aggregation reaction and robustly distinguish between patients with PD and non-disease controls. The ultrasensitivity of the assay affords the ability to detect minute quantities of αSyn in peripheral tissues, but it also produces various technical challenges of variability. To address the problem of variability, we present a high-yield αSyn protein purification protocol for the efficient production of monomers with a low propensity for self-aggregation. We expressed wild-type αSyn in BL21 Escherichia coli, lysed the cells using osmotic shock, and isolated αSyn using acid precipitation and fast protein liquid chromatography (FPLC). Following purification, we optimized the ionic strength of the reaction buffer to distinguish the fluorescence maximum (Fmax) separation between disease and healthy control tissues for enhanced assay performance. Our protein purification protocol yielded high quantities of αSyn (average: 68.7 mg/mL per 1 L of culture) and showed highly precise and robust αSyn-SAA results using brain, skin, and SMGs with inter-lab validation. [ABSTRACT FROM AUTHOR]

Chronic environmental exposure to toxic heavy metals, which often occurs as a mixture through occupational and industrial sources, has been implicated in various neurological disorders, including Parkinsonism. Vanadium pentoxide (V2O5) typically presents along with manganese (Mn), especially in welding rods and high-capacity batteries, including electric vehicle batteries; however, the neurotoxic effects of vanadium (V) and Mn co-exposure are largely unknown. In this study, we investigated the neurotoxic impact of MnCl2, V2O5, and MnCl2-V2O5 co-exposure in an animal model. C57BL/6 mice were intranasally administered either de-ionized water (vehicle), MnCl2 (252 µg) alone, V2O5 (182 µg) alone, or a mixture of MnCl2 (252 µg) and V2O5 (182 µg) three times a week for up to one month. Following exposure, we performed behavioral, neurochemical, and histological studies. Our results revealed dramatic decreases in olfactory bulb (OB) weight and levels of tyrosine hydroxylase, dopamine, and 3,4-dihydroxyphenylacetic acid in the treatment groups compared to the control group, with the Mn/V co-treatment group producing the most significant changes. Interestingly, increased levels of α-synuclein expression were observed in the substantia nigra (SN) of treated animals. Additionally, treatment groups exhibited locomotor deficits and olfactory dysfunction, with the co-treatment group producing the most severe deficits. The treatment groups exhibited increased levels of the oxidative stress marker 4-hydroxynonenal in the striatum and SN, as well as the upregulation of the pro-apoptotic protein PKCδ and accumulation of glomerular astroglia in the OB. The co-exposure of animals to Mn/V resulted in higher levels of these metals compared to other treatment groups. Taken together, our results suggest that co-exposure to Mn/V can adversely affect the olfactory and nigral systems. These results highlight the possible role of environmental metal mixtures in the etiology of Parkinsonism. [ABSTRACT FROM AUTHOR]

MXene and nonwoven carbon fabric are good candidate for flexible, light‐weight electromagnetic interference (EMI) shielding fabric. The prepared composite was characterized using X‐ray diffraction, X‐ray photo electron spectroscopy, energy‐dispersive X‐ray spectroscopy, scanning electron microscope, mapping, and Raman spectroscopy. The 15 times coated composite displayed a contact angle of 123°, a wetting energy of −39.86 mN/m, a spreading coefficient of −112.66 mN/m, and 32.94 mN/m work of adhesion. The fabricated composites inhibited thermal degradation until 235 °C. The composite revealed an excellent electric conductivity of 8.5 S/cm with a sheet resistance of 6.5 Ω/sq. The composite showed a maximum EMI shielding of 43.2 dB at 2.3 GHz with 8534.7 dB cm2/g. The composite displays better outlook application areas such as aviation, portable electronics, radars, aerospace, and military. [ABSTRACT FROM AUTHOR]

This review highlights the recent technologies of H2S removal from wastewater in the petroleum refinery. H2S is a harmful, putrid, and hazardous gaseous compound. The main processes such as physicochemical, chemical, biological, and electrochemical methods were compared and discussed in detail. The effects of various parameters and adsorbent characteristics were highlighted and correlated with the adsorption capacities. Surface functional groups and porosity surface area play a crucial role in the process of single-phase and composite adsorbents. Composite materials impregnated with some metals showed high removal efficiencies. It was found that the adsorption process is the most relevant way for H2S removal due to its high removal efficiency, low cost, eco-friendly, and operational simplicity. This study serves as a useful guideline for those who are interested in H2S removal. [ABSTRACT FROM AUTHOR]

Liquefaction of unsaturated sands has been observed in laboratory tests and in the field. A comprehensive investigation of unsaturated sand deposits subjected to seismic loading, especially using validated computational tools, is still lacking. This paper presents an analysis procedure to study the response of level ground unsaturated sand deposits subjected to seismic loading. The analysis procedure is a fully coupled flow-deformation finite element code with solid skeleton displacements, pore water pressure, and pore air pressure as nodal variables. The stress-strain behavior of unsaturated sands is described by a coupled hydro-mechanical elastoplastic constitutive model that includes the hysteretic model for soil water characteristic curves and the hydro-mechanical coupling mechanisms. The finite element code is first validated by comparing simulations with centrifuge test results. Reasonable comparisons of surface accelerations, ground settlements, and lateral deformations are obtained. A parametric study is then conducted to investigate the effects of initial degree of saturation, relative density, and effective overburden pressure on the seismic response of level ground unsaturated sand deposits. The results of the parametric study show that the thickness of the liquefied layer increases with an increase in degree of saturation. The potential for liquefaction reduced with increases in relative density and effective overburden stress. The results also reveal a drastic reduction in surface accelerations following liquefaction of a sand deposit. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bayesian optimized MLP-ANNs were applied for modelling biochar & syngas productions. • 60 ANN models were configured based on different hyperparameters tuning. • The MLP-ANN with topology of 3–2-10–10-1 predicted biochar yield most accurately. • Bayesian optimized models facilitates the accurate prediction of the biochar and syngas yield. Biochar and syngas are important products of pyrolysis that can be employed for a wide range of applications such as catalysts for biodiesel production, wastewater treatment, and the production of oxygenated fuel. This study employs Bayesian optimized multilayer perceptron neural network for modelling the prediction of biochar and syngas from pyrolysis of biomass-derived wastes. Sixty neural networks were configured by considering the effect of hyperparameters such as the connecting layers of the network, the size of the network, and the type of neural network algorithms. The feature analysis using F-test algorithms revealed that temperature, biomass composition, N 2 flow rates, residence time, and bed height influence the biochar and syngas yield obtained from the pyrolysis process. There is a significant interaction effect between the features as shown by the parametric analysis. The performance of the neural networks was significantly influenced by the number of connecting layers and the size of the hidden neurons. The five-layer neural network with an architecture of 3–2-10–10-1 displayed the best performance in predicting the biochar yield obtained from the pyrolysis process as indicated by R2 of 0.984, and RMSE of 0.34. While the five-layer neural network with an architecture of 3–7-10–3-1 displayed the best performance in predicting the syngas yield from the pyrolysis process as indicated by R2 of 0.999. [ABSTRACT FROM AUTHOR]

The oxidative stress-sensitive protein kinase Cδ (PKCδ) has been implicated in dopaminergic neuronal cell death. However, little is known about the epigenetic mechanisms regulating PKCδ expression in neurons. Here, we report a novel mechanism by which the PKCδ gene can be regulated by histone acetylation. Treatment with histone deacetylase (HDAC) inhibitor sodium butyrate (NaBu) induced PKCδ expression in cultured neurons, brain slices, and animal models. Several other HDAC inhibitors also mimicked NaBu. The chromatin immunoprecipitation analysis revealed that hyperacetylation of histone H4 by NaBu is associated with the PKCδ promoter. Deletion analysis of the PKCδ promoter mapped the NaBu-responsive element to an 81-bp minimal promoter region. Detailed mutagenesis studies within this region revealed that four GC boxes conferred hyperacetylation-induced PKCδ promoter activation. Cotransfection experiments and Sp inhibitor studies demonstrated that Sp1, Sp3, and Sp4 regulated NaBu-induced PKCδ up-regulation. However, NaBu did not alter the DNA binding activities of Sp proteins or their expression. Interestingly, a one-hybrid analysis revealed that NaBu enhanced transcriptional activity of Sp1/Sp3. Overexpression of the p300/cAMP-response element-binding protein-binding protein (CBP) potentiated the NaBu-mediated transactivation potential of Sp1/Sp3, but expressing several HDACs attenuated this effect, suggesting that p300/CBP and HDACs act as coactivators or corepressors in histone acetylation-induced PKCδ up-regulation. Finally, using genetic and pharmacological approaches, we showed that NaBu up-regulation of PKCδ sensitizes neurons to cell death in a human dopaminergic cell model and brain slice cultures. Together, these results indicate that histone acetylation regulates PKCδ expression to augment nigrostriatal dopaminergic cell death, which could contribute to the progressive neuropathogenesis of Parkinson disease. [ABSTRACT FROM AUTHOR]

Abstract: Parkinson's disease is a progressive neurodegenerative disease in the elderly, and no cure or disease-modifying therapies exist. Several lines of evidence suggest that mitochondrial dysfunction and oxidative stress have a central role in the dopaminergic neurodegeneration of Parkinson's disease. In this context, mitochondria-targeted therapies that improve mitochondrial function may have great promise in the prevention and treatment of Parkinson's disease. In this review, we discuss the recent developments in mitochondria-targeted antioxidants and their potential beneficial effects as a therapy for ameliorating mitochondrial dysfunction in Parkinson's disease. This article is part of a Special Issue entitled: Misfolded Proteins, Mitochondrial Dysfunction, and Neurodegenerative Diseases. [Copyright &y& Elsevier]

Epidemiological evidence indicates chronic environmental exposure to transition metals may play a role in chronic neurodegenerative conditions such as Parkinson's disease (PD). Chronic inhalation exposure to welding fumes containing metal mixtures may be associated with development of PD. A significant amount of vanadium is present in welding fumes, as vanadium pentoxide (V2O5), and incorporation of vanadium in the production of high strength steel has become more common. Despite the increased vanadium use in recent years, the neurotoxicological effects of this metal are not well characterized. Recently, we demonstrated that V2O5 induces dopaminergic neurotoxicity via protein kinase C delta (PKCδ)-dependent oxidative signaling mechanisms in dopaminergic neuronal cells. Since anosmia (inability to perceive odors) and non-motor deficits are considered to be early symptoms of neurological diseases, in the present study, we examined the effect of V2O5 on the olfactory bulb in animal models. To mimic the inhalation exposure, we intranasally administered C57 black mice a low-dose of 182µg of V2O5 three times a week for one month, and behavioral, neurochemical and biochemical studies were performed. Our results revealed a significant decrease in olfactory bulb weights, tyrosine hydroxylase (TH) levels, levels of dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC) and increases in astroglia of the glomerular layer of the olfactory bulb in the treatment groups relative to vehicle controls. Neurochemical changes were accompanied by impaired olfaction and locomotion. These findings suggest that nasal exposure to V2O5 adversely affects olfactory bulbs, resulting in neurobehavioral and neurochemical impairments. These results expand our understanding of vanadium neurotoxicity in environmentally-linked neurological conditions. [ABSTRACT FROM AUTHOR]

3- O -deacetylteugracilin ( 1 ) and teugracilin B ( 2 ), two natural stereoisomers, are isolated from Teucrium yemense (Defl). These two compounds are almost identical to each other, differing only at the C6 stereocenter. We now crystallise these two compounds and for the first time, determine the crystal structure through single crystal X-ray diffraction, and the stereochemistry for all positions using spectroscopic data. These techniques enable us to establish the difference between the two compounds. Careful interpretation of the results indicates that HRMS and 1 and 2D NMR spectroscopy, are in agreement with single crystal X-ray diffraction data. [ABSTRACT FROM AUTHOR]

An experimental comparison of four different methods of nearfield acoustic holography (NAH) for planar acoustic sources is presented in this study. The four NAH methods considered in this study are based on: (1) spatial Fourier transform, (2) equivalent sources model, (3) boundary element methods and (4) statistically optimized NAH. Two dimensional measurements were obtained at distances ranging from one-half to sixteen microphone spacings away from a sound source and the NAH methods were used to reconstruct the sound field at the source surface. Reconstructed particle velocity and acoustic pressure fields presented in this study showed that the equivalent sources model based algorithm along with Tikhonov regularization provided the best localization of the sources. Reconstruction errors were found to be smaller for the equivalent sources model based algorithm and the statistically optimized NAH algorithm. The effects of hologram distance on the performance of various algorithms are discussed in detail. The study also compares the computational time required by each algorithm to calculate the reconstruction. Four different regularization parameter choice methods were compared. The L-curve method provided more accurate reconstructions than the generalized cross validation and the Morozov discrepancy principle at larger measurement distances. The performance of fixed parameter regularization was comparable to that of the L-curve method. [ABSTRACT FROM AUTHOR]

Centrifuge tests were performed to investigate the effects of ground improvement on the seismic behavior of pile groups in soft clay. The soil profile consisted of four lightly overconsolidated clay layers overlying a dense layer of sand. The pile groups had a symmetrical layout consisting of 2×2 piles spaced at 3.0 pile diameters and were driven into both unimproved soft clay and soft clay improved by a simulated Cement Deep Soil Mixing (CDSM) method. The centrifuge model was subjected to seven different earthquake events with peak accelerations ranging from 0.03 to 0.66 g . The foundation level motions of the improved pile groups were different than the surface free-field motion. The foundation level motion for the unimproved pile group was, however, identical to that in the free-field. Higher peak accelerations were observed in the pile cap of the group with smaller CDSM block (GIS) compared to the unimproved pile group (GU) and the group with the largest CDSM block (GIL). Higher pile cap to the soil surface spectral ratios were also obtained for the GIS group in both short and long periods. Cement-Deep-Soil-Mixing was effective in reducing the peak displacements of the GIL pile cap. The peak displacements of the GIS pile cap remained about the same as the GU pile cap. As the size of the ground improvement increased, the fundamental period of the pile groups reduced. The estimated fundamental periods of the GIS and GU pile groups were, however, close to each other. Acceleration and displacement response spectra of the foundation level motions in comparison to the fundamental periods of the pile groups provided insight into the observed acceleration and displacement responses. The adhesion between soft clay and CDSM blocks helped to reduce the soft clay settlement in the vicinity of CDSM blocks compared to the free-field and the vicinity of unimproved pile group. More residual excess pore water pressure was, however, generated in the vicinity of CDSM blocks compared to the free-field and the corresponding location in the unimproved pile group, likely due to vibrations of the CDSM blocks and the piles. [ABSTRACT FROM AUTHOR]

The use of p-multipliers in the analysis of the lateral loading behavior of pile groups is based on the concept of modifying the singlepile p-y curve to obtain the p-y curve for a pile in a group. The p-multipliers account for the reduced soil resistance mobilized at a given deflection as a result of overlapping of shear zones. Different factors can influence the p-multipliers; however, because of the lack of experimental data, most researchers and design guidelines consider only the normalized pile spacing in the direction of loading in their recommendations. In this study, the effects of pile spacing and clay stiffness on the p-multipliers were investigated using the results of two series of centrifuge tests. The soil profile consisted of four lightly overconsolidated clay layers overlying a dense sand layer. The pile groups had a symmetrical layout consisting of 2 × 2 piles spaced at center-to-center distances of 3.0 and 7.0 pile diameter (D) and were driven into improved (stiff clay) and unimproved soft clay. Ground improvement was done in situ using simulated cement deep soil mixing (CDSM). Computer analyses were performed to back-calculate the p-multipliers. There was very good agreement between the measured and computed responses for both the leading and trailing rows of piles in the unimproved and improved soft clay. The results reveal that increasing the clay stiffness and pile spacing in the direction of loading increase p-multipliers. No pile-soil-pile interaction was observed for the 7D spacing. The proposed set of p-multipliers for the soft clay was found to be in close agreement with some current guidelines, whereas other design guidelines appear to recommend relatively conservative values of p-multipliers for both soft and stiff clay (improved ground). [ABSTRACT FROM AUTHOR]

• Data-driven modeling of biohydrogen yield from photocatalytic conversion of wastewater. • Application of multilayer perceptron neural network (MLPNN) and nonlinear autoregressive neural network (NARX) • Trained model using Levenberg-Marquardt (LM), Bayesian regularization (BR) and scaled conjugate gradient (SCG) algorithms. • MLPNN-BR model outperformed with R2 of 0.999 and RMSE of 0.138. The quest for energy and environmental sustainability necessitates an increasing interest in the photocatalytic conversion of wastewater to biohydrogen. However, the complexity of the photocatalytic conversion and the low productivity of the biohydrogen produced has become a major concern in the scale-up of the process. This study employs a data-driven approach to model biohydrogen production from the photocatalytic conversion of wastewater. Having ascertained the influence of five different parameters namely catalyst size, reaction temperature, catalyst among, irradiation time, and radiation intensity on the biohydrogen production through parametric analysis, the data were employed to model the process using multilayer perceptron neural network (MLPNN) and nonlinear autoregressive neural network (NARX). Both the MLPNN and NARX models were trained using Levenberg-Marquardt (LM), Bayesian regularization (BR), and scaled conjugate gradient (SCG) algorithms. The performance of 20 network architectures was tested for MLPNN-LM, MLPNN-BR, MLPNN-SCG, NARX-LM, NARX-BR, and NARX-SCG. The analysis revealed that the best network architectures of 5-14-1, 5-11-1, 5-7-1, 5-14-1, 5-15-1, and 5-7-1 were obtained for the MLPNN-LM, MLPNN-BR, MLPNN-SCG, NARX-LM, NARX-BR, and NARX-SCG, respectively. All the models demonstrated a good predictability of the biohydrogen production as evidenced by the coefficient of determination (R2) > 0.9 and low root mean square error (RMSE) values. The best performance was displayed by MLPNN-BR model with R2 of 0.999 and RMSE of 0.138. The independent variable analysis shows that all the factors significantly influence the predicted biohydrogen production. The catalyst size has the most significant effect on the predicted hydrogen production as indicated by the importance value of 0.329. [ABSTRACT FROM AUTHOR]

Abstract: The role of normal cellular prion protein (PrP) remains to be fully elucidated; however, the protein is crucial for the infection and progression of prion diseases. Recent evidence indicates that PrP is a metalloprotein since the octapeptide repeat sequences in the protein have high affinity for various divalent cations and the binding sites appear to play a role in the pathogenesis of prion diseases. In our present study, we tested several divalent metals including manganese and cadmium and determined their effects on protein degradation and protein aggregation in mouse neuronal cells expressing PrP. Cadmium was more neurotoxic than manganese following 24h exposure. Manganese did not show any significant effect on the inhibition of proteasomal activity or formation of high molecular weight ubiquitinated PrPs. Interestingly, treatment with cadmium profoundly inhibited proteasomal activity, which resulted in greatly increased formation of high molecular weight ubiquitinated PrPs. Immunohistochemical analysis also revealed a dramatic increase in formation of oligomers after cadmium treatment. Cadmium also increased the formation of ubiquitinated PrP, but it did not lead to the formation of proteinase-K resistant PrP. Collectively, our results show that a divalent metal, cadmium affects proteasomal function and PrP aggregation, which promote neurotoxicity. [Copyright &y& Elsevier]

Abstract: Exposure to environmental neurotoxic metals, pesticides and other chemicals is increasingly recognized as a key risk factor in the pathogenesis of chronic neurodegenerative disorders such as Parkinson''s and Alzheimer''s diseases. Oxidative stress and apoptosis have been actively investigated as neurotoxic mechanisms over the past two decades, resulting in a greater understanding of neurotoxic processes. Nevertheless, emerging evidence indicates that epigenetic changes, protein aggregation and autophagy are important cellular and molecular correlates of neurodegenerative diseases resulting from chronic neurotoxic chemical exposure. During the Joint Conference of the 13th International Neurotoxicology Association and the 11th International Symposium on Neurobehavioral Methods and Effects in Occupational and Environmental Health, the recent progress made toward understanding epigenetic mechanisms, protein aggregation, autophagy, and deregulated kinase activation following neurotoxic chemical exposure and the relevance to neurodegenerative conditions were one of the themes of the symposium. Dr. Anumantha G. Kanthasamy described the role of acetylation of histones and non-histone proteins in neurotoxicant-induced neurodegenerative processes in the nigral dopaminergic neuronal system. Dr. Arthi Kanthasamy illustrated the role of autophagy as a key determinant in cell death events during neurotoxic insults. Dr. Ajay Rana provided evidence for posttranslational modification of α-synuclein protein by the Mixed Linage Kinase (MLK) group of kinases to initiate protein aggregation in cell culture and animal models of Parkinson''s disease. These presentations outlined emerging cutting edge mechanisms that might set the stage for future mechanistic investigations into new frontiers of molecular neurotoxicology. This report summarizes the views of symposium participants, with emphasis on future directions for study of environmentally and occupationally linked chronic neurodegenerative diseases. [Copyright &y& Elsevier]

Background: Parkinson's disease (PD) is a devastating neurodegenerative disorder characterized by progressive motor debilitation, which affects several million people worldwide. Recent evidence suggests that glial cell activation and its inflammatory response may contribute to the progressive degeneration of dopaminergic neurons in PD. Currently, there are no neuroprotective agents available that can effectively slow the disease progression. Herein, we evaluated the anti-inflammatory and antioxidant efficacy of diapocynin, an oxidative metabolite of the naturally occurring agent apocynin, in a pre-clinical 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Methods: Both pre-treatment and post-treatment of diapocynin were tested in the MPTP mouse model of PD. Diapocynin was administered via oral gavage to MPTP-treated mice. Following the treatment, behavioral, neurochemical and immunohistological studies were performed. Neuroinflammatory markers, such as ionized calcium binding adaptor molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), gp91phox and inducible nitric oxide synthase (iNOS), were measured in the nigrostriatal system. Nigral tyrosine hydroxylase (TH)-positive neurons as well as oxidative markers 3-nitrotyrosine (3-NT), 4-hydroxynonenal (4-HNE) and striatal dopamine levels were quantified for assessment of the neuroprotective efficacy of diapocynin. Results: Oral administration of diapocynin significantly attenuated MPTP-induced microglial and astroglial cell activation in the substantia nigra (SN). MPTP-induced expression of gp91phox and iNOS activation in the glial cells of SN was also completely blocked by diapocynin. Notably, diapocynin markedly inhibited MPTP-induced oxidative markers including 3-NT and 4-HNE levels in the SN. Treatment with diapocynin also significantly improved locomotor activity, restored dopamine and its metabolites, and protected dopaminergic neurons and their nerve terminals in this pre-clinical model of PD. Importantly, diapocynin administered 3 days after initiation of the disease restored the neurochemical deficits. Diapocynin also halted the disease progression in a chronic mouse model of PD. Conclusions: Collectively, these results demonstrate that diapocynin exhibits profound neuroprotective effects in a pre-clinical animal model of PD by attenuating oxidative damage and neuroinflammatory responses. These findings may have important translational implications for treating PD patients. [ABSTRACT FROM AUTHOR]