Investigation on Mechanical Properties of Aluminum 8011 Metal Matrix Compositewith Titanium Carbide Particulate Reinforcement

Aluminium metal matrix composites are the key material in engineering fields like aerospace, defense, automobiles and consumer goods. Aluminium matrix composite dominates the conventional materials due to its low economic rate, high wear resistance and strength to weight ratio. So, the present work considered Al 8011 alloy as the metal matrix and titanium carbide (TiC) particles as reinforced material for investigation. The composite was prepared by stir casting method. A digital pin on disc tester was used to measure the wear with EN32 steel disc as counter surface (72HRC) and cylindrical pin as the composite specimens. The present tests were conducted for various sliding velocity of 1,57 m/s, 2,62 m/s and 3,67 m/s. The normal load of 20 N, 40 N, 60 N and the filler content of 0%, 10%, 20% have been considered for the sliding distance of 1000, 3000 and 5000 m. The results of new composite show better wear resistance than matrix metal. The micro structural characterization of worn surface was investigated using De-wintor inverted trinocular metallurgical microscope. Prepared polished matrix shows the distribution of TiC particles in Al 8011 metal matrix based on the quantity added. The impact energy of the samples was found using Izod impact testing machine. Final results showed improved mechanical properties for Al 8011 with 7% TiC compared with other two samples

A Prospective study of Upper Gastrointestinal Endoscopic findings in patients presenting with dyspepsia

Dyspepsia is affecting about 25% of general population in developed nations and it is a major cause for medical visits. New patients comprise about 10% of population every year. Dyspepsia majorly affects quality of life and it is a major burden in view of social costs. Directly the expenses are for laboratory tests, medical consultation and drugs and indirectly by absence from work. Dyspepsia refers to spectrum of diseases and heterogeneous group of symptoms confined to upper abdomen. Dyspepsia is a vague term used to explain upper abdominal collection of symptoms like indigestion, fullness, early satiety (not able to complete the meals), bloating, belching, nausea, epigastric discomfort or pain and anorexia. Indigestion is very common in general population; almost all have had indigestion at some time in their lifetime. Sometimes patients will include constipation and undigested food particles in the stool. OBJECTIVES: 1. To evaluate the upper gastro intestinal endoscopic findings in patients presenting with dyspepsia 2. To detect esophago gastroduodenal carcinoma at an earlier stage 3. To study the age and sex prevalence in patients presenting with dyspepsia. METHODOLOGY: A prospective clinical study was undertaken at Madurai medical college hospital, Madurai to know the various upper gastro-intestinal endoscopic findings in patients presenting with dyspepsia. The study was conducted from march 2016 to August 2016. The patient selection was by convenience sampling. Dyspeptic patients were included in this study with their informed consent. A detailed clinically history was elucidated, followed by careful clinical examination, which were recorded as per the proforma. All the patients included in the study underwent upper gastrointestinal endoscopy and the findings were noted. The inclusion and exclusion criterias were as follows: Inclusion criteria: 1. Patients above 18 years of age. 2. Patients showing symptoms of dyspepsia. 3. Patients who have consented for the study Exclusion criteria: 1. Patients below 18 years of age, 2. Patients with chronic liver disease, 3. Patients who has not consented for the study. RESULTS After informed consent 110 cases of dyspepsia were included in the study and were studied clinically as per the proforma from March 2016 to August 2016. All the patients underwent upper gastro-intestinal endoscopy and various findings were noted. Out of 110 patients, 86 (78.1%) patients had epigastric pain and discomfort as their chief complaint whereas nausea and vomiting was present in 74 (67.27%) patients. The other complaints were heart burn 67 (60.9%), food intolerance 50 (45.4%), indigestion 52 (47.27%) and loss of appetite and weight 35 (31.81%). In this study 66% were male patients, 44% were female patients. The incidence of different presentations of dyspepsia were more common in males compared to females. clinically significant endoscopic findings were observed in 61 patients accounting for 55.45%. Gastritis was by far the most common finding (24.54%). The next common findings were duodenitis, and gastric ulcer accounting for 7.2% each. There were 6 patients with carcinoma stomach accounting for 5.4%, among them which 3 were male patients and 3 were female patients. Gastric malignancies were common in older age groups The following were the observations: 1. Highest prevalence of dyspepsia in the age group of 30-39 years 2. Most common presenting complaint was epigastric pain and discomfort 3. Dyspepsia was more common in males (60%) when compared to females (40%) 4. Most common endoscopic finding was normal study followed by gastritis 5. Malignancy was diagnosed in 5.4% patients with dyspepsia. 6. Stomach is the common site of lesion in patients presenting with dyspepsia 7. Gastritis, duodenitis, gastric ulcer, is more common in males than females presenting with dyspepsia. 8. Incidence of malignancy increases as the age advances. CONCLUSION From the present study of "A Prospective study of upper gastro-intestinal endoscopy findings in patients presenting with dyspepsia ". Endoscopic examination revealed gastritis which accounted for the majority of the cases. Incidence of malignancy in the present study was observed to be 5.4% (gastric malignancies). Clinically significant endoscopic findings were observed in 55.45% of patients with uninvestigated dyspepsia. Most patients presented with a complex of three or more dyspeptic symptoms and the symptom profile was not predictive of the endoscopic findings. Prevalence of large number of inflammatory lesions as a result of increased acid production and low incidence of malignancy in the study group suggests that the uninvestigated patients with dyspepsia may be initially managed medically with acid suppressive therapy

Graph theoretic network analysis reveals protein pathways underlying cell death following neurotropic viral infection

Complex protein networks underlie any cellular function. Certain proteins play a pivotal role in many network configurations, disruption of whose expression proves fatal to the cell. An efficient method to tease out such key proteins in a network is still unavailable. Here, we used graph-theoretic measures on protein-protein interaction data (interactome) to extract biophysically relevant information about individual protein regulation and network properties such as formation of function specific modules (sub-networks) of proteins. We took 5 major proteins that are involved in neuronal apoptosis post Chandipura Virus (CHPV) infection as seed proteins in a database to create a meta-network of immediately interacting proteins (1st order network). Graph theoretic measures were employed to rank the proteins in terms of their connectivity and the degree upto which they can be organized into smaller modules (hubs). We repeated the analysis on 2nd order interactome that includes proteins connected directly with proteins of 1st order. FADD and Casp-3 were connected maximally to other proteins in both analyses, thus indicating their importance in neuronal apoptosis. Thus, our analysis provides a blueprint for the detection and validation of protein networks disrupted by viral infections

Bacterial foraging-optimized PID control of a two-wheeled machine with a two-directional handling mechanism

This paper presents the performance of utilizing a bacterial foraging optimization algorithm on a PID control scheme for controlling a five DOF two-wheeled robotic machine with two-directional handling mechanism. The system under investigation provides solutions for industrial robotic applications that require a limited-space working environment. The system nonlinear mathematical model, derived using Lagrangian modeling approach, is simulated in MATLAB/Simulink(®) environment. Bacterial foraging-optimized PID control with decoupled nature is designed and implemented. Various working scenarios with multiple initial conditions are used to test the robustness and the system performance. Simulation results revealed the effectiveness of the bacterial foraging-optimized PID control method in improving the system performance compared to the PID control scheme

Cerebral Blood Volume Changes During Radiotherapy May Predict Pseudoprogression versus Disease Progression for Patients with High Grade Glioma

https://openworks.mdanderson.org/sumexp21/1040/thumbnail.jp

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Stroke genetics informs drug discovery and risk prediction across ancestries

Previous genome-wide association studies (GWASs) of stroke - the second leading cause of death worldwide - were conducted predominantly in populations of European ancestry(1,2). Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis(3), and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach(4), we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry(5). Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries.</p

Stroke genetics informs drug discovery and risk prediction across ancestries

Previous genome-wide association studies (GWASs) of stroke — the second leading cause of death worldwide — were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Large scale functional brain networks underlying temporal integration of audio-visual speech perception: An EEG study

Observable lip movements of the speaker influence perception of auditory speech. A classical example of this influence is reported by listeners who perceive an illusory (cross-modal) speech sound (McGurk-effect) when presented with incongruent audio-visual (AV) speech stimuli. Recent neuroimaging studies of AV speech perception accentuate the role of frontal, parietal and the integrative brain sites in the vicinity of the superior temporal sulcus (STS) for multisensory speech perception. However, if and how does the network across the whole brain participates during multisensory perception processing remains an open question. We posit that a large-scale functional connectivity among the neural population situated in distributed brain sites may provide valuable insights involved in processing and fusing of AV speech. Varying the psychophysical parameters in tandem with electroencephalogram (EEG) recordings, we exploited the trial-by-trial perceptual variability of incongruent audio-visual (AV) speech stimuli to identify the characteristics of the large-scale cortical network that facilitates multisensory perception during synchronous and asynchronous AV speech. We evaluated the spectral landscape of EEG signals during multisensory speech perception at varying AV lags. Functional connectivity dynamics for all sensor pairs was computed using the time-frequency global coherence, the vector sum of pairwise coherence changes over time. During synchronous AV speech, we observed enhanced global gamma-band coherence and decreased alpha and beta-band coherence underlying cross-modal (illusory) perception compared to unisensory perception around a temporal window of 300-600 ms following onset of stimuli. During asynchronous speech stimuli, a global broadband coherence was observed during cross-modal perception at earlier times along with pre-stimulus decreases of lower frequency power, e.g., alpha rhythms for positive AV lags and theta rhythms for negative AV lags. Thus, our study indicates that the temporal integration underlying multisensory speech perception requires to be understood in the framework of large-scale functional brain network mechanisms in addition to the established cortical loci of multisensory speech perception