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Nanostructured Fe-18Cr-2Si alloys were developed by a combination of mechanically alloying (MA) and spark plasma sintering (SPS) process. SPS was carried out in vacuum at three different temperatures (900, 1000, and 1100 °C) with a fixed holding time of 10 min and an applied pressure of 50 MPa. Potentiodynamic polarization (PDP), linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS) were used to study the effect of sintering temperature on the electrochemical properties of newly developed nanostructured ferritic Fe-18Cr-2Si alloy. XRD results showed that, after sintering, crystallite size increased with increasing sintering temperature and maximum crystallite size was 23.64 nm. The results showed that with increasing sintering temperature, corrosion resistance was increased in terms of pitting potential (Epit), passive current density (ip), and polarization resistance (Rp). The improved corrosion resistance was found to be closely related with the densification of the sintered alloys. [ABSTRACT FROM AUTHOR]

The paper deals with solid particle erosion downstream of a sharp-edged orifice commonly found in many chemical processing industries. The orifice is installed in a pipe that is long enough to ensure fully developed turbulent flow in both upstream and downstream directions. Both the k-ε model and the Lagrangian particle-tracking technique were used for predicting solid particle trajectories. Gambit 2.2 was used to construct the computational grid and the commercial Fluent 12.1 code was used to perform the calculations. The available erosion correlations were used for determination of erosion characteristics considering carbon steel and aluminum pipes. The investigation was carried out for a flow restricting orifice of fixed geometry and pipe flow velocities in the range 1-4 m/s using solid particle of diameters 50-500 µm. The results indicated two critical erosion regions downstream of the orifice: the first is in the immediate neighborhood of the orifice plate and the second is in the flow reattachment zone. The results showed also a strong dependence of erosion on both particle size and flow velocity. [ABSTRACT FROM AUTHOR]

Effect of copper on the defect density of Fe-20Cr- xCu ( x = 0, 4) stainless steel alloys was investigated in deaerated pH 8·5 borate buffer solution at room temperature using Mott-Schottky analysis. Mott-Schottky analysis revealed that the addition of copper increased the acceptor density (NA, VCr−3), i.e. decreased the Cr+3 content of the passive film. Also the donor densities, shallow donor (ND1, VO+2) and deep donor (ND2, VCr+6), of the passive films formed were increased. XPS analysis confirmed the decrease in Cr content and enrichment of copper in the passive film of Cu containing alloys, which ultimately dictated their lower corrosion resistance, i.e. decreased film protectiveness and stability. [ABSTRACT FROM AUTHOR]

Arsenic contamination in drinking water is one of the major causes of arsenicosis, a clinical syndrome due to drinking arsenic-rich water. Data on arsenic concentration levels in drinking water is lacking in Pakistan. Knowledge of arsenic concentration in ground water used for drinking is essential to introduce a strategy to avoid arsenic contamination associated with health hazards. The present work deals with the assessment of arsenic concentration levels in ground water in eight provincial districts of Punjab, Pakistan. During a study conducted in 2001-03 by the provincial Local Government and Community Development department in the Punjab province, 4,547 drinking water samples were collected and analyzed using atomic absorption spectrometry technique. The results show that arsenic levels in drinking water varied from 6 to 12 ng ml-1 with a mean value of 8.5±1.6 ng ml-1, which is below the recommended World Health Organization (WHO) guidelines of 10 ng ml-1 for drinking water. The data generated in this study will provide base line values for monitoring arsenic concentrations in drinking water in the surveyed area. [ABSTRACT FROM AUTHOR]

Laser treatment of an aluminum composite surface was carried out to improve tribological properties and corrosion resistance at the surface. The workpiece consists of 15% SiC and pure aluminum, and it is produced by hot pressing. The characteristics of the laser-treated surface were examined using optical and scanning electron microscopes, energy dispersive spectroscopy, X-ray diffraction, a micro-tribometer, and a potentiostat. Laser treatment was carried out by following a spiral scanning track at the surface. This provides a self-annealing effect of the lately formed laser tracks on the initially formed tracks while lowering the cooling rates at the surface. It was found that laser-treated surfaces are free from asperities such as large-scale cracks and voids. Laser treatment improves the hardness of the surface because of the dense layer formation in the surface region. The friction coefficient of the laser-treated surface attains lower values than that corresponding to the untreated surface. Laser treatment improves the corrosion resistance of the surface.

This article focuses on a study that compares poorer short term outcome in indo-asians and Caucasians after percutaneous coronary intervention (PCI) for ethnicity as an independent risk factor. Despite the complex nature of this patient group there is a low incidence of tropinin elevation and myocardial necrosis following PCI. Coronary artery disease tends to be more extensive and diffuse in Indo-Asians (IA) as compared with Caucasians. There are, however, few data relating to ethnicity and outcome after revoscularisation. Ethnicity in relation to lAs emerged as an independent risk factor for poor short term outcome following PCI.

Hydrogen generation through the hydrolysis of aluminum alloys has attracted significant attention because it generates hydrogen directly from alkaline water without the need for hydrogen storage technology. The hydrogen generation rate from the hydrolysis of aluminum in alkaline water is linearly proportional to its corrosion rate. To accelerate the corrosion rate of the aluminum alloy, we designed Al-Ni alloys by continuously precipitating an electrochemically noble Al 3 Ni phase along the grain boundaries. The Al-0.5~1 wt.% Ni alloys showed an excellent hydrogen generation rate of 16.6 mL/cm2·min, which is about 6.4 times faster than that of pure Al (2.58 mL/cm2·min). This excellent performance was achieved through the synergistic effects of galvanic and intergranular corrosion on the hydrolysis of Al. By raising the solution temperature to 50 °C, the optimal rate of hydrogen generation of Al-1 wt.% Ni in 10 wt.% NaOH solutions at 30 °C can be further increased to 54.5 mL/cm2·min.

Rationale: Mitigating the spread of COVID-19 requires that people understand the need for and engage in protective behaviors. Given the complexity and rapid progression of media information about the pandemic, health literacy could be essential to acquiring the accurate beliefs, concern for societal risks, and appreciation of restrictive policies needed to motivate these behaviors. Yet with the increasingly politicized nature of COVID-related issues in the United States, health literacy could be an asset for those with more liberal views but less so for those with more conservative views., Objective: This study tested a hypothesized model proposing that political views moderate the associations of health literacy with COVID-19 protective behaviors as well as the mediational roles of accurate and inaccurate COVID-19 beliefs, concern for society, and governmental control attitudes., Methods: We surveyed residents in three diverse regions of California in June 2020 (N = 669) and February 2021 (N = 611). Participants completed measures of health literacy, political views, and COVID-19 beliefs and behaviors., Results: Moderated mediational analyses largely supported the proposed model with both samples. Health literacy was associated with more accurate COVID-19 beliefs, less inaccurate COVID-19 beliefs, greater concern for societal risks, more positive attitudes regarding restrictive government control, more protective behavior, less risky behavior, and stronger vaccine intentions; beliefs, concern for society, and governmental control attitudes mediated the health literacy-behavior relationships. As predicted, however, these associations of health literacy with adaptive beliefs, attitudes, and behaviors varied according to political views. The direct and mediated relationships were held for participants with more liberal views and, to a lesser extent, for those with moderate views, but they were weaker or absent for participants with more conservative views., Conclusions: These findings contribute new evidence of processes linking health literacy with adaptive beliefs, attitudes, and behaviors and how social and political contexts can shape those processes., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Research in the neurobiology of sex differences is inherently influenced by the study species that are used. Some traditional animal research models, such as rats and mice, show certain sex differences in the brain that have been foundational to neurobiological research. However, subsequent work has demonstrated that these differences are not always generalizable, especially to species with different social structures and sex-associated roles or behaviors. One such example is the naked mole-rat (Heterocephalus glaber), which has an unusual social structure among mammals. Naked mole-rats live in large groups where reproduction is restricted to a dominant female, called the "queen," and often only one breeding male. All other animals in the group, the "subordinates," are socially suppressed from reproduction and remain in a prepubescent state as adults, unless they are removed from the presence of the queen. These subordinates show little to no sex differences in external morphology, neural morphology, or behavior. However, there are a suite of neurobiological differences between subordinate and breeding naked mole-rats. After naked mole-rats attain breeding status, many of the classically sexually differentiated brain regions increase in volume (paraventricular nucleus, medial amygdala, bed nucleus of the stria terminalis). There are additionally social status differences in sex hormone receptor expression in the brain, as well as other changes in gene expression, some of which also show sex differences - though not always in the predicted direction based on other rodent studies. Data from naked mole-rats show that it is critical to consider the evolved social structure of a species when studying sex differences in the brain., (© 2022. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Historically, oral and dental issues for head and neck cancer patients were often not considered until after cancer treatment was complete. As a result, outcomes for oral rehabilitation were sometimes suboptimal. Inconsistencies in service delivery models and qualification, training and experience of staff delivering dental care often compounded this problem, making research and audit almost impossible. Collaborative working by consultants in restorative dentistry from all over the UK as part of a Restorative Dentistry-UK (RD UK) subgroup, renamed more recently as the RD-UK Head and Neck Cancer Clinical Excellence Network (CEN), has re-emphasised the importance of specialist restorative dentistry intervention at the outset of the head and neck cancer pathway to optimise outcomes of patient care. The CEN has driven several initiatives, reflecting Getting It Right First Time (GIRFT) principles aimed at reducing unwarranted variation. This improved consistency in approach and optimised collaborative working of the team now presents a better environment for multicentre audit and research. Ultimately, this should result in a continued improvement in patient and carer experience., (© 2022. The Author(s).)

In some cooperatively breeding groups, individuals have distinct behavioral characteristics that are often stable and predictable across time. However, in others, as in the eusocial naked mole-rat, evidence for behavioral phenotypes is ambiguous. Here, we study whether the naked mole-rat can be divided into discrete phenotypes and if circulating hormone concentrations underpin these differences. Naked mole-rat colonies consist of a single breeding female and large numbers of non-reproductive subordinates that in some cases can exceed several hundred in a colony. The subordinates can potentially be divided into soldiers, who defend the colony; workers, who maintain it; and dispersers, who want to leave it. We established six colonies de novo, tracked them over three years, and assessed the behavior and hormone concentrations of the subordinates. We found that soldiers tended to be from earlier litters and were higher ranked compared to workers, whereas dispersers were distributed throughout litters and rankings. There was no difference in estradiol, testosterone, or dehydroepiandrosterone (DHEA) concentrations among phenotypes. Progesterone concentrations were higher in soldiers, but this difference appeared to be driven by a few individuals. Principal component analysis demonstrated that soldiers separated into a discrete category relative to workers/dispersers, with the highest ranked loadings being age, body mass, and testosterone concentrations. However, the higher testosterone in soldiers was correlated with large body size instead of strictly behavioral phenotype. Workers and dispersers have more overlap with each other and no hormonal differences. Thus the behavioral variation in subordinate naked mole-rats is likely not driven by circulating steroid hormone concentrations, but rather it may stem from alternative neural and/or neuroendocrine mechanisms., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In many social species, hierarchical status within the group is associated with differences in basal adrenocortical activity. We examined this relationship in naked mole-rats (Heterocephalus glaber), eusocial rodents with arguably the most extreme social hierarchies of all mammals. This species lives in colonies where breeding is restricted to one socially dominant 'queen' and her male consorts, and all other individuals are reproductively suppressed 'subordinates'. The relationship between cortisol and social status in naked mole-rats has not fully been elucidated, as prior results on this topic have been contradictory. We used non-invasive feces sampling to measure baseline cortisol levels in eight laboratory colonies of naked mole-rats, to either replicate or reject rank differences. First, we successfully validated an assay to measure fecal cortisol metabolites (FCMs). Removal from the colony for the validation experiment, either alone or with an opposite sex conspecific, induced prolonged elevation of FCM levels on a scale of days to weeks. This increase in cortisol did not prevent the removed animals from sexually maturing. In colony-housed animals, we found no relationship between rank in the social hierarchy and FCM levels. Further, queens, breeding males, and reproductively suppressed subordinates all had equivalent FCM levels. We conclude that this species shows little evidence of the 'stress of dominance' or 'stress of subordination' and that reproductive suppression in naked mole-rats is not driven by elevated cortisol levels., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A technology based on velocity ratio indices is described for application in the myocardium. Angle-independent Doppler indices, such as the pulsatility index, which employ velocity ratios, can be measured even if the ultrasound beam vector at the moving target and the motion vector are not in a known plane. The unknown plane situation is often encountered when an ultrasound beam interrogates sites in the myocardium. The velocities employed in an index calculation must be close to the same or opposite directions. The Doppler velocity ratio indices are independent of angle in 3D space as are ratio indices based on 1D strain and 1D speckle tracking. Angle-independent results with spectral Doppler methods are discussed. Possible future imaging techniques based on velocity ratios are presented. By using indices that involve ratios, several other sources of error cancel in addition to that of angular dependence for example errors due to less than optimum gain settings and beam distortion. This makes the indices reliable as research or clinical tools. Ratio techniques can be readily implemented with current commercial blood flow pulsed wave duplex Doppler equipment or with pulsed wave tissue Doppler equipment. In 70 patients where the quality of the real-time B-mode looked suitable for the Doppler velocity ratio technique, there was only one case where clear spectra could not be obtained for both the LV wall and the septum. A reproducibility study of spectra from the septum of the heart shows a 12% difference in velocity ratios in the repeat measurements., (© 2019 The authors)

Multiple resident cell types contribute to maintaining the structure and physiological function of the heart over the life course. Cardiomyocyte proliferation supports scar free regeneration in the neonatal heart following injury, but a lower rate of proliferation in the adult necessitates replacement by a collagen scar to maintain ventricular integrity. In this short review we discuss recent studies that have identified novel roles for non-myocyte resident cells and the extracellular matrix in supporting repair, as well as cardiomyocyte and vascular regeneration, following myocardial infarction.

The vast majority of what is considered fact about adult neurogenesis comes from research on laboratory mice and rats: where it happens, how it works, what it does. However, this relative exclusive focus on two rodent species has resulted in a bias on how we think about adult neurogenesis. While it might not prevent us from making conclusions about the evolutionary significance of the process or even prevent us from generalizing to diverse mammals, it certainly does not help us achieve these outcomes. Here, we argue that there is every reason to expect striking species differences in adult neurogenesis: where it happens, how it works, what it does. Species-specific adaptations in brain and behavior are paramount to survival and reproduction in diverse ecological niches and it is naive to think adult neurogenesis escaped these evolutionary pressures. A neuroethological approach to the study of adult neurogenesis is essential for a comprehensive understanding of the phenomenon. Furthermore, most of us are guilty of making strong assertions about our data in order to have impact yet this ultimately creates bias in how work is performed, interpreted, and applied. By taking a step back and actually placing our results in a much larger, non-biomedical context, we can help to reduce dogmatic thinking and create a framework for discovery.

Background: Preclinical data suggest that an acute inflammatory response following myocardial infarction (MI) accelerates systemic atherosclerosis. Using combined positron emission and computed tomography, we investigated whether this phenomenon occurs in humans., Methods and Results: Overall, 40 patients with MI and 40 with stable angina underwent thoracic 18F-fluorodeoxyglucose combined positron emission and computed tomography scan. Radiotracer uptake was measured in aortic atheroma and nonvascular tissue (paraspinal muscle). In 1003 patients enrolled in the Global Registry of Acute Coronary Events, we assessed whether infarct size predicted early (≤30 days) and late (>30 days) recurrent coronary events. Compared with patients with stable angina, patients with MI had higher aortic 18F-fluorodeoxyglucose uptake (tissue-to-background ratio 2.15±0.30 versus 1.84±0.18, P<0.0001) and plasma C-reactive protein concentrations (6.50 [2.00 to 12.75] versus 2.00 [0.50 to 4.00] mg/dL, P=0.0005) despite having similar aortic (P=0.12) and less coronary (P=0.006) atherosclerotic burden and similar paraspinal muscular 18F-fluorodeoxyglucose uptake (P=0.52). Patients with ST-segment elevation MI had larger infarcts (peak plasma troponin 32 300 [10 200 to >50 000] versus 3800 [1000 to 9200] ng/L, P<0.0001) and greater aortic 18F-fluorodeoxyglucose uptake (2.24±0.32 versus 2.02±0.21, P=0.03) than those with non-ST-segment elevation MI. Peak plasma troponin concentrations correlated with aortic 18F-fluorodeoxyglucose uptake (r=0.43, P=0.01) and, on multivariate analysis, independently predicted early (tertile 3 versus tertile 1: relative risk 4.40 [95% CI 1.90 to 10.19], P=0.001), but not late, recurrent MI., Conclusions: The presence and extent of MI is associated with increased aortic atherosclerotic inflammation and early recurrent MI. This finding supports the hypothesis that acute MI exacerbates systemic atherosclerotic inflammation and remote plaque destabilization: MI begets MI., Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01749254., (© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

The assessment of myocardial ischemia represents a cornerstone in our approach to coronary artery disease. Indeed many of the clinical decisions we make revolve around the results of stress testing, the assessment of coronary luminal stenoses and, more recently, fractional flow reserve measurements. Whilst the assessment of ischemia is often useful with respect to diagnosis and its treatment important in terms of symptom relief, whether ischemia directly leads to adverse cardiovascular outcomes, in particular myocardial infarction, is much more controversial. Indeed this is one of the key questions facing cardiology practice today and the focus of an ongoing multimillion-dollar study, the ISCHEMIA trial. In this editorial the authors examine some of the underlying evidence and ask the question: is ischemia itself really bad for you?

Accurately assessing an individual's risk of myocardial infarction or stroke using currently available risk stratification tools remains a challenge, even in patients with symptomatic disease. Inflammation, micro-calcification and intra-plaque angiogenesis occur during the development and ultimate rupture of vulnerable plaques. Molecular imaging techniques such as combined positron emission tomography and computed tomography (PET/CT) offer the opportunity to target these key cellular processes within atheroma and identify high-risk lesions. In this review we will set out the studies that have demonstrated the feasibility of PET/CT imaging in assessing atherosclerotic plaque inflammation, micro-calcification and angiogenesis. We will also discuss the potential of PET/CT molecular imaging as both a screening tool for novel therapeutic interventions and as a means of improving cardiovascular risk stratification.

Neutralizing injurious stimuli, proinflammatory mediator catabolism, and polymorphonuclear leukocyte (PMN) clearance are determinants of inflammatory resolution. To this, we recently added innate-type lymphocyte repopulation as being central for restoring postinflammation tissue homeostasis with a role in controlling innate immune-mediated responses to secondary infection. However, although macrophages dominate resolution, their phenotype and role in restoring tissue physiology once inflammation abates are unknown. Therefore, we isolated macrophages from the resolving phase of acute inflammation and found that compared with classically activated proinflammatory M1 cells, resolution-phase macrophages (rMs) possess weaker bactericidal properties and express an alternatively activated phenotype but with elevated markers of M1 cells including inducible cyclooxygenase (COX 2) and nitric oxide synthase (iNOS). This phenotype is controlled by cAMP, which, when inhibited, transforms rM to M1 cells. Conversely, elevating cAMP in M1 cells transforms them to rMs, with implications for cAMP in the resolution of systemic inflammation. It transpires that although rMs are dispensable for clearing PMNs during self-limiting inflammation, they are essential for signaling postresolution lymphocyte repopulation via COX 2 lipids. Thus, rM macrophages are neither classically nor alternatively activated but a hybrid of both, with a role in mediating postresolution innate-lymphocyte repopulation and restoring tissue homeostasis.

Introduction: The tissue renin-angiotensin system is implicated in the pathogenesis of coronary artery disease (CAD). As locally synthesised aldosterone is a potential mediator of CAD, we have sought an association of the -344T>C variant of the aldosterone synthase (CYP11B2) gene with CAD events., Methods: Subjects comprised of the Second Northwick Park Heart Study (NPHSII), a prospective study of unrelated, healthy middle-aged Caucasian males. CAD events were recorded in 2490 subjects, and defined as a sudden cardiac death, myocardial infarction or coronary artery revascularisation procedure. Mean follow-up was 10.8 years. Aldosterone synthase genotype was determined in 2490 subjects. Power calculation suggests that we have 80% power (at a significance level of 0.05) to detect a difference in hazard ratio (HR) between homozygote groups of 0.45., Results: One hundred and eighty-seven CAD events were recorded in 2490 subjects. In the group overall, CAD events were independent of genotype with adjusted hazard ratios being 1.00 versus 1.25 versus 0.80 for TT versus TC versus CC genotypes, respectively, P = 0.07. Genotype interactions with smoking and blood pressure were sought. Whilst CAD events were independent of genotype amongst non-smokers, CC genotype in smokers was associated with a reduced risk HR 2.02 versus 2.28 versus 0.82 for TT versus TC versus CC genotypes, P = 0.05 (HR for TT + TC versus CC were 1.77 versus 0.67, P = 0.02). This apparent interaction remained after adjustment for conventional risk factors. No such interaction was found with blood pressure., Conclusions: Aldosterone synthase genotype is unrelated to overall CAD events risk. A possible interaction with smoking requires confirmation.