61871 research outputs found
Sort by
Editorial: New challenges and future perspectives in neurodegeneration
Get PDFOver the last decade, there has been growing interest and important developments in neurodegeneration research. These advances have been fostered by improvements in the research techniques that enable us to collect novel data understand the disease process(es) and underlying mechanisms better. In this Research Topic, we encouraged researchers to summarize their state-of-the-art methods, findings, and the main challenges that the field of neurodegeneration is facing..
Taking the plunge: When is best for hot water immersion to complement exercise in heat and hypoxia
No full textThis investigation assessed the psycho-physiological and performance effects of hot water immersion (HWI) implemented either before or after a repeated-sprint training in hypoxia (RSH) session conducted in the heat. Ten participants completed three RSH trials (3 × 10 × 5-s sprints), conducted at 40°C and simulated altitude of 3000 m. A 30-min monitoring period preceded and followed all exercise sessions. In PRE, the pre-exercise period was HWI, and the post-exercise period was seated rest in temperate conditions. This combination was reversed in POST. In CON, participants were seated in temperate conditions for both periods. Compared to CON, PRE elicited a reduction in power output during each repeated-sprint set (14.8–16.2%, all p < 0.001), and a significantly higher core temperature (Tc) during the pre-exercise period and throughout the exercise session (p < 0.001 and p = 0.025, respectively). In POST, power output and Tc until the end of exercise were similar to CON, with Tc higher at the conclusion of the post-exercise period (p < 0.001). Time across the entire protocol spent ≥38.5°C Tc was significantly longer in PRE (48.1 ± 22.5 min) than POST (31.0 ± 11.3 min, p = 0.05) and CON (15.8 ± 16.3 min, p < 0.001). Employing HWI following RSH conducted in the heat provides effective outcomes regarding physiological strain and cycling performance when compared to pre-exercise or no HWI
Characterizing the metabolic effects of the selective inhibition of gut microbial β-glucuronidases in mice
Get PDFThe hydrolysis of xenobiotic glucuronides by gut bacterial glucuronidases reactivates previously detoxified compounds resulting in severe gut toxicity for the host. Selective bacterial β-glucuronidase inhibitors can mitigate this toxicity but their impact on wider host metabolic processes has not been studied. To investigate this the inhibitor 4-(8-(piperazin-1-yl)-1,2,3,4-tetrahydro-[1,2,3]triazino[4′,5′:4,5]thieno[2,3-c]isoquinolin-5-yl)morpholine (UNC10201652, Inh 9) was administered to mice to selectively inhibit a narrow range of bacterial β-glucuronidases in the gut. The metabolomic profiles of the intestinal contents, biofluids, and several tissues involved in the enterohepatic circulation were measured and compared to control animals. No biochemical perturbations were observed in the plasma, liver or gall bladder. In contrast, the metabolite profiles of urine, colon contents, feces and gut wall were altered compared to the controls. Changes were largely restricted to compounds derived from gut microbial metabolism. This work establishes that inhibitors targeted towards bacterial β-glucuronidases modulate the functionality of the intestinal microbiota without adversely impacting the host metabolic system
Inactivated pentavalent vaccine against mycoplasmosis and salmonellosis for chickens
Get PDFMycoplasma and Salmonella are serious pathogens threaten the poultry industry. This study aimed to prepare and evaluate an inactivated pentavalent vaccine targeting bacteria, including Salmonella enterica serovar Typhimurium (ST), Salmonella enterica serovar Enteritidis (SE), Salmonella enterica serovar Kentucky (SK), Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS), from locally isolated strains. The prepared vaccine was adjuvanted with Montanide ISA70 oil and then tested for safety, sterility, and potency. The vaccine efficacy was evaluated in 110 specific pathogen-free, 1-day-old chicks, which were divided into three groups as follows: 1) vaccinated group (50 birds), which was subdivided into five subgroups of ten birds each; 2) control positive (challenged) group (50 birds), which was subdivided into five subgroups of ten birds each; and 3) control negative (blank) group, which included ten birds. Chicks in group 1 were administered the first dose of vaccine at 7 d of age followed by a booster dose after 3 wk. At 3 wk after booster vaccination, the chicks who were administered the booster dose were challenged and kept under observation until the end of the experiment when the chicks were approximately 10 wk. Details of clinical symptoms, daily mortality, weights, and postmortem lesions; serum samples; cloacal swabs; and nasal swabs were collected during the experiment. The humoral immune response to the prepared pentavalent vaccine was assessed using enzyme-linked immunosorbent assay. Our findings revealed that the prepared vaccine showed high protective antibody titers against Salmonella and Mycoplasma with 100% efficacy and no mortalities (100% survival rate) were recorded in vaccinated and challenged birds. The vaccine reduced both clinical signs and bacterial shedding post challenge in vaccinated birds in comparison with control positive group. The prepared vaccine did not affect the body weight gain of the vaccinated birds in comparison with control negative birds. The current study concluded that locally manufactured inactivated pentavalent vaccine offers protection to birds and could be employed as an effective tool along with biosecurity measures to overcome mycoplasmosis and salmonellosis in layer and breeder chicken farms in Egypt
Daily timing of low tide drives seasonality in intertidal emersion mortality risk
Get PDFSea level exerts a fundamental influence on the intertidal zone, where organisms are subject to immersion and emersion at varying timescales and frequencies. While emersed, intertidal organisms are exposed to atmospheric stressors which show marked diurnal and seasonal variability, therefore the daily and seasonal timing of low water is a key determinant of survival and growth in this zone. Using the example of shallow coral reefs, the coincidence of emersion with selected stressors was investigated for eight locations around the Australian coastline. Hourly water levels (1992 – 2016) from a high-resolution sea level hindcast (http://sealevelx.ems.uwa.edu.au), were linked to maximum surface solar radiation data from the Copernicus ERA5 atmospheric model and minimum atmospheric temperature observations from the Australian Bureau of Meteorology to identify seasonal patterns and historical occurrence of coral emersion mortality risk. Local tidal characteristics were found to dictate the time of day when low water, and therefore emersion mortality risk occurs, varying on a seasonal and regional basis. In general, risk was found to be greatest during the Austral spring when mean sea levels are lowest and a phase change in solar tidal constituents occurs. For all Great Barrier Reef sites, low tide occurs close to midday during winter and midnight in the summer, which may be fundamental factor supporting the historical bio-geographical development of the reef. Interannual variability in emersion mortality risk was mostly driven by non-tidal factors, particularly along the West Coast where El Niño events are associated with lower mean sea levels. This paper highlights the importance of considering emersion history when assessing intertidal environments, including shallow coral reef platform habitats, where critical low water events intrinsically influence coral health and cover. The study addresses a fundamental knowledge gap in both the field of water level science and intertidal biology in relation to the daily timing of low tide, which varies predictably on a seasonal and regional basis
Structuring professional dialogue through protocols: A study among elementary English teachers in Taiwan
No full textThis study focuses on the integration of protocols into elementary school English teacher’s professional dialogue and discusses the influence of protocols on teacher’s teaching and learning. Based on the analysis of documents, observations, and interviews, this study concludes that the introduction of protocols to elementary school English teachers led them to discuss their classroom practice and gain professional learning in instructional strategies and student learning during the professional dialogue. However, English teacher’s lack of experience in using protocols led to interruptions during the professional dialogue. Suggestions for effective protocol-based professional dialogue are provided
Investigation of the effect of different parameters on lixiviant ion migration in a laboratory scale study of electrokinetic in-situ recovery
No full textIn situ recovery (ISR) has the potential to recover metals at a lower cost, create less waste and significantly reduce energy usage and the environmental footprint of a mining operation compared with conventional mining. Only preliminary research has been conducted on ISR-related mass transfer enhancement methods. Improved mass transfer may allow for greater contact of lixiviant with ore surfaces in an ISR operation, improved leaching kinetics and an increased overall metal recovery from the in-situ environment. One approach to improve mass transfer in ISR is to use an electrokinetic method. The electrokinetic method induces ion migration using an electric potential difference across a medium immersed in liquid. The focus of this study was twofold: to evaluate the effect of different parameters on the migration of ions in an electrokinetic setup and to propose a standard laboratory-scale setup to perform mass transfer measurements for ISR. A series of experiments were conducted in which the propagation of lixiviant solution in an electrokinetic setup was monitored and the experimental results were analyzed by different methods. Experiments were performed using different voltages (but in a constant voltage setup) using two experimental setup configurations (with and without hydraulic pressure), synthetic core samples of different permeabilities and different membrane types at the ends of the experimental setup middle section. It was found that an increase in applied voltage across a non-reactive silica sample increased ion migration. At 20 V and above, more ions moved to the target reservoir over 4 days compared with 15 V, and at 15 V, more time was needed to reach maximum ion migration. The use of different membrane types did not affect lixiviant ion migration significantly. Lower-permeability synthetic core samples hindered lixiviant ion migration
The use of black pepper (Piper guineense) as an ecofriendly antimicrobial agent to fight foodborne microorganisms
No full textConsumers demand clean-label food products, necessitating the search for new, natural antimicrobials to meet this demand while ensuring food safety. This review aimed at investigating the antimicrobial properties of black pepper (Piper guineense) against foodborne microorganisms. The existence of foodborne illness, food spoilage, food waste, the resulting negative economic impact of these issues, and consumer interests have all pushed the food industry to find alternative, safe, and natural antimicrobials to be used in foods and beverages. Consumers have also influenced the demand for novel antimicrobials due to the perceived association of current synthetic preservatives with diseases and adverse effects on children. They also have a desire for clean-label products. These combined concerns have prompted researchers at investigating plant extracts as potential sources for antimicrobials. Plants possess many antimicrobial properties; therefore, evaluating these plant extracts as a natural source of antimicrobials can lead to a preventative control method in reducing foodborne illness and food spoilage, inclusively meeting consumer needs. In most regions, P. guineense is commonly utilized due to its potent and effective medicinal properties against foodborne microorganisms
The foundations of Pakistan’s strategic culture: Fears of an irredentist India, Muslim identity, martial race, and political realism
Get PDFThis article examines the early foundations of the strategic culture of the Pakistan Army. By exploring the impact of the partition of British India in 1947 and the First Kashmir War of 1947–48, the article identifies the pivotal factors in the development of strategic culture of Pakistan. In also examining Pakistani fears of a “vengeful” Hindu India and a persistence in the belief of discredited martial race theories as well as the idea of a Muslim military exceptionalism, the article concludes that the foundation of this culture remains evident while it is also malleable to contemporaneous events
Breast milk production in women who use nipple shields for persistent nipple pain
No full textObjective
To examine relationships between nipple pain scores and 24-hour milk production volumes, breastfeeding and pumping frequencies, and breastfeeding duration in women using nipple shields for persistent nipple pain.
Design
Secondary outcome analysis of a prospective cohort study.
Setting
Research laboratory and participants’ homes.
Participants
Twenty-five breastfeeding women (6 ± 4 weeks after birth) who used nipple shields for persistent nipple pain.
Methods
We conducted a randomized trial to investigate the primary outcome of milk transfer with and without nipple shields among participants with and without nipple pain. Here, we report secondary outcomes of associations between 24-hour milk production, breastfeeding and pumping frequencies, breastfeeding durations, and intake in participants using a nipple shield for nipple pain. Participants completed demographic, health and breastfeeding questionnaires and, at two monitored breastfeeding sessions, completed a pain visual analogue scale and Brief Pain Inventory–Short Form (BPI-SF; total and subscale scores for pain interference with General Activity, Mood, Sleep, and Breastfeeding). Milk production (milliliters per 24 hours), feed volumes, and percentage of available milk removed were calculated from data and milk samples obtained by participants over one 24-hour period and at study visits. Participants logged 24-hour data on a customized research website. We used descriptive statistics as well as simple and multiple linear regression for analyses.
Results
Milk production and feeding duration were not associated with nipple pain scores (visual analogue scale: p = .80, BPI-SF: p = .44). An increase in BPI-SF Breastfeeding subscale score of 1 unit, indicating pain interference with breastfeeding, was associated with a 0.28 decrease in 24-hour breastfeeding frequency (p = .02) and an 18.8-ml decrease in 24-hour breastfeeding intake (p = .04).
Conclusion
Persistent nipple pain was associated with reduced breastfeeding frequency; therefore, continuing professional support is required to ensure adequate milk removal and pain management