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To determine whether: the N95 respirator affects nasal valve patency; placement on the bony vault improves patency; and external nasal anatomy affects the outcome.
A prospective study with 50 participants was conducted. Nasal patency was measured by the minimal cross-sectional area via acoustic rhinometry, and using the Nasal Obstruction Symptom Evaluation survey, before and after wearing the N95 respirator and after adjustment.
The minimal cross-sectional area was narrowed by 27 per cent when wearing the N95 respirator (p < 0.001), and improved by 9.2 per cent after adjustment (p = 0.003). The total Nasal Obstruction Symptom Evaluation score increased from 10.2 to 25.4 after donning the N95 respirator (p < 0.001), and decreased from 25.4 to 15.6 after adjustment (p < 0.001). There was no correlation with external nasal anatomy parameters.
Wearing the N95 respirator causes narrowing of the nasal valve, and adjustment onto the bony vault improves symptoms. The findings were not affected by external nasal anatomy.
Background: Embolization represents a minimally invasive treatment modality for arteriovenous malformations (AVMs), tumors, aneurysms, and vessel sacrifice, but can be limited by currently available embolization agents. Discovery of new and improved agents could lead to better treatment outcomes. The goal of this project was to develop and test a novel embolization agent using hydrogels, a class of materials which may be bioengineered to suit a variety of indications. Methods: We devised a method of liquid hydrogel embolization with photo-modulated crosslinking for intravascular solidification, using a custom microcatheter set-up. We tested this in swine blood vessels (n=3), the swine renal arterial trees as a vascular tumor model (n=5), and the swine arterial-arterial networks of the rete mirabile as an AVM model (n=3). Hydrogel embolization was assessed for treatment efficacy and safety. Follow-up angiography was performed at 2-4 week intervals. Results: Hydrogel embolization was technically successful in all animals, with full occlusion of the vascular target immediately following embolization and at follow-up. There were no instances of clinical or angiographic complications. Conclusions: We demonstrated a novel method of dynamic photomodulation and delivery of bioengineered hydrogels to address current limitations of endovascular embolization therapies. This promising technology will be investigated further with longer-term comparative animal trials.
Background: The mechanism of aneurysmal healing after flow-diversion treatment of cerebral aneurysms remains unknown. The purpose of this research to is to utilize a novel technology called endovascular optical coherence tomography (OCT) to characterise and improve our understanding of aneurysmal healing after flow-diversion using a rabbit aneurysm model. Methods: Saccular aneurysms were created in 10 New Zealand white rabbits. The aneurysms were treated with a flow-diverting stent 28 days after creation. OCT and histopathologic examinations included: luminal thrombosis, endothelial loss, inflammation, fibrin, smooth muscle cell loss, disruption of the internal and external elastic lamina, and tunica adventitia changes Results: OCT revealed endothelialization across the stent, appearing to originate from the parent vessel, along with small amounts of thrombus on the stent-struts. Minimal thrombus was visualized within the aneurysm sac. Histologic examination revealed that OCT can accurately define endothelialization across the sent, and define patent segments across the neck. Conclusions: Aneurysmal healing appears to originate at the parent vessel/stent interface, and use the stent as a scaffold to grow across the neck of the aneurysm. Minimal thrombus was visualized within the aneurysm sac, with ongoing flow observed in the setting of incomplete neck endothelialization. This technology has great potential for assessing aneurysmal healing in real-time.
Repetitive transcranial magnetic stimulation has been employed to treat drug dependence, reduce drug use and improve cognition. The aim of the study was to analyze the effectiveness of intermittent theta-burst stimulation (iTBS) on cognition in individuals with methamphetamine use disorder (MUD).
This was a secondary analysis of 40 MUD subjects receiving left dorsolateral prefrontal cortex (L-DLPFC) iTBS or sham iTBS for 20 times over 10 days (twice-daily). Changes in working memory (WM) accuracy, reaction time, and sensitivity index were analyzed before and after active and sham rTMS treatment. Resting-state EEG was also acquired to identify potential biological changes that may relate to any cognitive improvement.
The results showed that iTBS increased WM accuracy and discrimination ability, and improved reaction time relative to sham iTBS. iTBS also reduced resting-state delta power over the left prefrontal region. This reduction in resting-state delta power correlated with the changes in WM.
Prefrontal iTBS may enhance WM performance in MUD subjects. iTBS induced resting EEG changes raising the possibility that such findings may represent a biological target of iTBS treatment response.
Performance characteristics of SARS-CoV-2 nucleic acid detection assays are understudied within contexts of low pre-test probability, including screening asymptomatic persons without epidemiological links to confirmed cases, or asymptomatic surveillance testing. SARS-CoV-2 detection without symptoms may represent presymptomatic or asymptomatic infection, resolved infection with persistent RNA shedding, or a false-positive test. This study assessed the positive predictive value of SARS-CoV-2 real-time reverse transcription polymerase chain reaction (rRT-PCR) assays by retesting positive specimens from 5 pre-test probability groups ranging from high to low with an alternate assay.
In total, 122 rRT-PCR positive specimens collected from unique patients between March and July 2020 were retested using a laboratory-developed nested RT-PCR assay targeting the RNA-dependent RNA polymerase (RdRp) gene followed by Sanger sequencing.
Significantly fewer (15.6%) positive results in the lowest pre-test probability group (facilities with institution-wide screening having ≤3 positive asymptomatic cases) were reproduced with the nested RdRp gene RT-PCR assay than in each of the 4 groups with higher pre-test probability (individual group range, 50.0%–85.0%).
Large-scale SARS-CoV-2 screening testing initiatives among low pre-test probability populations should be evaluated thoroughly prior to implementation given the risk of false-positive results and consequent potential for harm at the individual and population level.
Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3−) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change.
Personal protective equipment (PPE) is worn by prehospital providers (PHPs) for protection from hazardous exposures. Evidence regarding the ability of PHPs to perform resuscitation procedures has been described in adult but not pediatric models. This study examined the effects of PPE on the ability of PHPs to perform resuscitation procedures on pediatric patients.
This prospective study was conducted at a US simulation center. Paramedics wore normal attire at the baseline session and donned full Level B PPE for the second session. During each session, they performed timed sets of psychomotor tasks simulating clinical care of a critically ill pediatric patient. The difference in time to completion between baseline and PPE sessions per task was examined using Wilcoxon signed-rank tests.
A total of 50 paramedics completed both sessions. Median times for task completion at the PPE sessions increased significantly from baseline for several procedures: tracheal intubation (+4.5 s; P = 0.01), automated external defibrillator (AED) placement (+9.5 s; P = 0.01), intraosseous line insertion (+7 s; P < 0.0001), tourniquet (+8.5 s; P < 0.0001), intramuscular injection (+21-23 s, P < 0.0001), and pulse oximetry (+4 s; P < 0.0001). There was no significant increase in completion time for bag-mask ventilation or autoinjector use.
PPE did not have a significant impact on PHPs performing critical tasks while caring for a pediatric patient with a highly infectious or chemical exposure. This information may guide PHPs faced with the situation of resuscitating children while wearing Level B PPE.
Large prospective observational studies have cast doubt on the common assumption that endovascular thrombectomy (EVT) is superior to intravenous thrombolysis for patients with acute basilar artery occlusion (BAO). The purpose of this study was to retrospectively review our experience for patients with BAO undergoing EVT with modern endovascular devices.
All consecutive patients undergoing EVT with either a second-generation stent retriever or direct aspiration thrombectomy for BAO at our regional stroke center from January 1, 2013 to March 1, 2019 were included. The primary outcome measure was functional outcome at 1 month using the modified Rankin Scale (mRS) score. Multivariable logistic regression was used to assess the association between patient characteristics and dichotomized mRS.
A total of 43 consecutive patients underwent EVT for BAO. The average age was 67 years with 61% male patients. Overall, 37% (16/43) of patients achieved good functional outcome. Successful reperfusion was achieved in 72% (31/43) of cases. The median (interquartile range) stroke onset to treatment time was 420 (270–639) minutes (7 hours) for all patients. The procedure-related complication rate was 9% (4/43). On multivariate analysis, posterior circulation Alberta stroke program early computed tomography score and Basilar Artery on Computed Tomography Angiography score were associated with improved functional outcome.
EVT appears to be safe and feasible in patients with BAO. Our finding that time to treatment and successful reperfusion were not associated with improved outcome is likely due to including patients with established infarcts. Given the variability of collaterals in the posterior circulation, the paradigm of utilizing a tissue window may assist in patient selection for EVT. Magnetic resonance imaging may be a reasonable option to determine the extent of ischemia in certain situations.
Addition of multispecies impurity ions to the total-f gyrokinetic particle-in-cell code XGCa is reported, including a cross-verification of neoclassical physics against the NEO code. This new version of the neoclassical gyrokinetic code XGCa is used to benchmark and confirm the previous reduced-equation-based prediction that high-$Z$ impurity particles in the Pfirsch–Schlüter regime can exhibit a significant level of up–down poloidal asymmetry, through the large parallel friction force, and thus influence the radial plasma transport significantly. The study is performed in a plasma with weak toroidal rotation. In comparison, when the impurity particles are in the plateau regime, the up–down poloidal asymmetry becomes weak, with the parallel friction force becoming weaker than the parallel viscous force. It is also found that the linearization of the perturbed distribution function, based on the small poloidal asymmetry assumption, can become invalid. Using the numerical data from XGCa, each term in the parallel fluid force-balance equation have been analysed to find that both the main ions and the electrons respond to the poloidal potential variation adiabatically when the high-$Z$ tungsten possesses large poloidal variation.
Intensive silvopastoral systems (ISS) are a sustainable alternative to monoculture systems (MS). The presence of trees and legumes improves animal welfare due to the increased food quality and quantity and the presence of shade while providing a variety of environmental services. As cattle behaviour is greatly affected by environmental conditions, knowledge on the behavioural trade-offs that cattle make to meet their demands while foraging in different grazing systems is important, as this will help us understand the perceived advantages of ISS. This pilot study assessed the behaviour of heifers in an ISS (n=8 heifers) and MS (n=8 heifers) in the Mexican tropics during the dry and rainy seasons, and its relationship with forage availability, mean travelled distance and the temperature humidity index (THI). In both seasons, daily foraging times were longer in the MS than the ISS (P<0.01). The duration of rumination was higher for ISS (P<0.01) and the duration of lying was higher for the dry season (P<0.05). The decrease in foraging times in relation to THI was significantly higher in the ISS than in the MS (mean slope±SE: ISS=−4.64±0.34; MS=−2.34±0.22; t=−14.20, P<0.001). The results suggest that the forage availability and access to shade in the ISS allow cattle to rest longer and increase rumination, whereas cattle in MS spend more time searching for food and foraging at times of the day were the temperatures were higher as a compensatory strategy, which potentially decreases cattle’s welfare and production qualities when compared with the ISS. In conclusion, ISS are likely to generate positive behavioural trade-offs that result in better welfare conditions and higher productive potential.
Monitoring milk quality traits and the classification of raw milk are important steps for generating high-quality dairy products. Given the important roles of the BRG1/BRM-associated factor 60c (BAF60c) gene in the regulation of physiological growth and production, the objective of the current study was to analyse the association between the BAF60c gene and milk quality and establish a gene-based method for pre-evaluating raw milk quality. For this purpose, DNA was isolated from 507 milk samples and genotyped using the polymerase chain reaction-restricted fragment length polymorphism method. Milk quality traits including milk protein percentage (MPP), milk fat percentage (MFP), lactose percentage (LP) and total solids content (TSC) were also evaluated from the same 507 milk samples. The newly found 6060 T > C mutation of the BAF60c gene was associated significantly with MPP and LP, but not with MFP and TSC. The results demonstrated that this mutation could be used for the pre-evaluation of MPP and LP; therefore, raw milk could be graded according to different genotypes.
While normative data on neuropsychological performance provide baseline metrics for the assessment and diagnosis of mild cognitive impairment and dementia, a lack of comparative normative data in non-Caucasian populations makes it difficult to conduct similar evaluations and studies in individuals from diverse backgrounds. The current paper aims to provide normative data on a range of cognitive measures in a Korean general population sample and investigate various demographic and health variables associated with cognitive performance in this representative population.
The study population was 1,528 stroke and dementia-free individuals who participated in the Korean Genome and Epidemiology study (KoGES) (mean age 60.43 ± 7.30, 52.42% female). All participants underwent a comprehensive neuropsychological test battery that included verbal and visual memory, language, attention, and executive function measures. A health examination and a questionnaire-based interview were also administered.
The majority of cognitive test results were associated with age, education, and gender. In general, higher education and younger age was associated with better cognitive performance. Explained variance increased modestly in models that included measures of general health and depressive symptoms.
Normative data of cognitive performance in a community based Korean population are presented. These norms provide reference values in a non-Caucasian middle to older aged sample.
Background: Despite increasing awareness of scientific fraud, no attempt has been made to assess its prevalence in neurosurgery. The aim of our review was to assess the chronological trend and reasons for the retraction of neurosurgical publications. Methods: We searched the EMBASE and MEDLINE databases using a comprehensive search strategy for retracted articles from January 1995 to December 2016. Archives of retracted articles on www.retractionwatch.com and the independent websites of neurosurgical journals were also searched. Data including the journal name and its impact factor, reason for retraction, country of origin, and citations were extracted. Results: A total of 72 studies were included for data extraction. Journal impact factor ranged from 0.24 to 14.4. Most studies(76%) were retracted within the last 5 years. The most common reason for retraction was because of a duplicated publication found elsewhere(25%), followed closely by plagiarism(21%), or falsifying data(17%). Other reasons included scientific errors/mistakes, author misattribution, and fraudulent peer review. Articles originated from several different countries and some were widely cited. Conclusions: Retractions of neurosurgical publications are increasing globally, mostly due to issues of academic integrity. Implementation of more transparent data sharing and screening as well as additional education for new researchers may help mitigate these issues moving forward.
Background: Results of previous studies examining seasonal variation in the incidence of aneurysmal subarachnoid hemorrhage (SAH) are conflicting. The aim of this study is to investigate whether there is a seasonal effect in online search queries for SAH that may reflect an association between meteorological factors and aneurysm rupture. Methods: We utilized the Google Trends data service to analyze the volume of internet queries for SAH on Google’s search engine from January 1, 2004 to November 2016. We used comprehensive search terms and collected data from: USA, Canada, Finland, and Japan, as well as worldwide search volume. Potential seasonal variations in the data were assessed by comparative non-parametric tests and curve-fit regression model. Results: Our analyses revealed that USA had the highest median search scores (115 vs. 86, 46, 46 for Finland, Canada and Japan, respectively). The term “brain aneurysm” was the commonly used search term among countries, followed by “cerebral aneurysm”. There was no evidence of seasonality in any of the countries studied on both univariate tests and regression time-adjusted analysis. Conclusions: There are no seasonal variations in internet search query volume for SAH. Further studies are needed to explore whether online search volumes correlate with the actual incidence of SAH.
An association between low levels of physical activity and impaired cognitive performance in schizophrenia has been proposed, but most studies have relied on self-report measures of activity. This study examined the association between actigraphy-derived physical activity and cognitive performance adjusting for multiple covariates in patients with schizophrenia.
Patients with schizophrenia (n = 199) were recruited from chronic psychiatric wards, and 60 age-, sex- and body mass index-matched comparison participants were recruited from the staff of two hospitals and universities. Physical activity was assessed objectively for 7 days using an ActiGraph. Cognitive performance was assessed with the Cognitrone test from the Vienna Test System and the Grooved Pegboard Test. Demographic variables, metabolic parameters, positive and negative symptoms, duration of illness and hospitalization, and medication use were included as covariates. Pearson correlations and multivariable linear regressions were conducted to examine the associations between physical activity levels and cognitive performance.
Patients with schizophrenia were less physically active and had poorer performance on attention/concentration and speed of processing than the comparison group. Patients with schizophrenia who spent more time in light physical activity showed better performance on attention/concentration (β = 0.198, p = 0.020) and speed of processing (β= −0.169, p = 0.048) tasks than those who were less active. Cognitive performance was also associated with moderate-vigorous physical activity, but the effect was no longer significant once light physical activity had been taken into account.
This study provides evidence for a positive association between objectively measured light physical activity and cognitive performance in people with schizophrenia, after adjustment for multiple confounders.
Thermal history and evolution of the Palaeozoic petroleum system of the western Lower Saxony Basin as well as charge history of the Apeldorn gas field was reconstructed using 2-D forward basin modelling software. The Apeldorn gas field is located on an inverted western rim of the Lower Saxony Basin (LSB) and belongs with its relatively anomalous nitrogen content of 73.9 vol. % to one of the most unique gas accumulations in North Germany. Based on thermal calibration studies utilising both, vitrinite reflectance and corrected bottom hole temperatures as calibration parameters, a shallow burial model and an anomalous event of Coniacian high heat flow of 80 to 120 mW/m2 was derived. As result, Lower Triassic and younger successions became subjected to slight changes in thermal maturity as opposed to Carboniferous and Permian successions, which show no assessable impact of the high heat flow event on the coalification pattern. The deep burial model in contrary to the shallow burial model is not supported by the structural reconstruction and backstripping in this more marginal setting. According to the modelling results, the key charge of the present Apeldorn gas field began in Tithonian (late Upper Jurassic) during the major phase of rifting in the Lower Saxony Basin. The present Westphalian coal-derived gas accumulations of the Lower Triassic Buntsandstein reservoir were sourced directly from modelled methane pools at top Rotliegend level. The hydrocarbon potential of the Westphalian source rocks became exhausted in Oxfordian (early Upper Jurassic). Reduction of the hydrostatic pressure during the Coniacian high heat flow event together with uplift during the Coniacian-Santonian inversion led to an extensive free gas exsolution. The resulting gas mixture between the exsolved free gas and the Westphalian coal-derived gas reached and saturated Buntsandstein reservoir. The structural trap became destroyed in course of the inversion leading to a sharp decrease of methane and nitrogen saturation.
Silvopastoral systems can be a good alternative for sustainable livestock production because they can provide ecosystem services and improve animal welfare. Most farm animals live in groups and the social organization and interactions between individuals have an impact on their welfare. Therefore, the objective of this study was to describe and compare the social behaviour of cattle (Bos indicus×Bos taurus) in a silvopastoral system based on a high density of leucaena (Leucaena leucocephala) combined with guinea grass (Megathyrsus maximus), star grass (Cynodon nlemfuensis) and some trees; with a monoculture system with C. nlemfuensis, in the region of Merida, Yucatán. Eight heifers in each system were observed from 0730 to 1530 h each day for 12 consecutive days during the dry season and 12 consecutive days during the rainy season. The animals followed a rotation between three paddocks, remaining 4 days in each paddock. The vegetation was characterized in the paddocks of the silvopastoral system to estimate the average percentage of shade provided. To make a comparison between systems, we used a t test with group dispersion, and Mann–Whitney tests with the frequency of affiliative and agonistic behaviours. We assessed differences in linearity and stability of dominance hierarchies using Landau’s index and Dietz R-test, respectively. The distance of cows with respect to the centroid of the group was shorter, and non-agonistic behaviours were 62% more frequent in the intensive silvopastoral system than in the monoculture one. Heifers in the silvopastoral system had a more linear and non-random dominance hierarchy in both seasons (dry season: h’=0.964; rainy season: h’=0.988), than heifers in the monoculture system (dry season: h’=0.571, rainy season: h’=0.536). The dominance hierarchy in the silvopastoral system was more stable between seasons (R-test=0.779) than in the monoculture system (R-test=0.224). Our results provide the first evidence that heifers in the silvopastoral system maintain more stable social hierarchies and express more sociopositive behaviours, suggesting that animal welfare was enhanced.
Non-alcoholic fatty liver disease (NAFLD) is significantly associated with hyperlipidaemia and oxidative stress. We have previously reported that astaxanthin (ASTX), a xanthophyll carotenoid, lowers plasma total cholesterol and TAG concentrations in apoE knockout mice. To investigate whether ASTX supplementation can prevent the development of NAFLD in obesity, male C57BL/6J mice (n 8 per group) were fed a high-fat diet (35 %, w/w) supplemented with 0, 0·003, 0·01 or 0·03 % of ASTX (w/w) for 12 weeks. The 0·03 % ASTX-supplemented group, but not the other groups, exhibited a significant decrease in plasma TAG concentrations, suggesting that ASTX at a 0·03 % supplementation dosage exerts a hypotriacylglycerolaemic effect. Although there was an increase in the mRNA expression of fatty acid synthase and diglyceride acyltransferase 2, the mRNA levels of acyl-CoA oxidase 1, a critical enzyme in peroxisomal fatty acid β-oxidation, exhibited an increase in the 0·03 % ASTX-supplemented group. There was a decrease in plasma alanine transaminase (ALT) and aspartate transaminase (AST) concentrations in the 0·03 % ASTX-supplemented group. There was a significant increase in the hepatic mRNA expression of nuclear factor erythroid 2-related factor 2 and its downstream genes, which are critical for endogenous antioxidant mechanism, in the 0·03 % ASTX-supplemented group. Furthermore, there was a significant decrease in the mRNA abundance of IL-6 in the primary splenocytes isolated from the 0·03 % ASTX-supplemented group upon lipopolysaccharide (LPS) stimulation when compared with that in the splenocytes isolated from the control group. In conclusion, ASTX supplementation lowered the plasma concentrations of TAG, ALT and AST, increased the hepatic expression of endogenous antioxidant genes, and rendered splenocytes less sensitive to LPS stimulation. Therefore, ASTX may prevent obesity-associated metabolic disturbances and inflammation.
The increasing prevalence of obesity in children and adolescents has become one of the most important public health issues around the world. Lack of physical activity is a risk factor for obesity, while being obese could reduce the likelihood of participating in physical activity. Failing to account for the endogeneity between obesity and physical activity would result in biased estimation. This study investigates the relationship between overweight and physical activity by taking endogeneity into consideration. It develops an endogenous bivariate probit model estimated by the maximum likelihood method. The data included 4008 boys and 4197 girls in the 5th–9th grades in Taiwan in 2007–2008. The relationship between overweight and physical activity is significantly negative in the endogenous model, but insignificant in the comparative exogenous model. This endogenous relationship presents a vicious circle in which lower levels of physical activity lead to overweight, while those who are already overweight engage in less physical activity. The results not only reveal the importance of endogenous treatment, but also demonstrate the robust negative relationship between these two factors. An emphasis should be put on overweight and obese children and adolescents in order to break the vicious circle. Promotion of physical activity by appropriate counselling programmes and peer support could be effective in reducing the prevalence of obesity in children and adolescents.