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As the coronavirus disease 2019 (COVID-19) continues to circulate, testing strategies are of the utmost importance. Given national shortages of testing supplies, personal protective equipment, and other hospital resources, diagnostic stewardship is necessary to aid in resource management. We report the low utility of serial testing in a low-prevalence setting.
Test the efficacy and perceived effectiveness of nutrition labels on children’s menus from a full-service chain restaurant in an online study.
Using a between-groups experiment, parents were randomised to view children’s menus displaying one of five children’s nutrition labelling conditions: (i) No Nutrition Information (control); (ii) Calories Only; (iii) Calories + Contextual Statement (CS); (iv) Calories, Sodium + CS; or (v) Calories and Sodium in Traffic Lights + CS. Parents hypothetically ordered up to one entrée, side, beverage and dessert for their child, then rated and ranked all five labelling conditions on the level of perceived effectiveness.
998 parents with a 3–12 year old child.
Parents exposed to menus displaying ‘Calories, Sodium + CS’ selected significantly fewer calories ‘overall’ (entrées + side + dessert + beverage) compared to parents exposed to the control condition (−53·1 calories, P < 0·05). Parents selected ‘entrees’ with significantly fewer calories and lower sodium when exposed to menus with ‘Calories + CS’ (−24·3 calories, P < 0·05); ‘Calories, Sodium + CS’ (−25·4 calories, −56·1 mg sodium, P < 0·05 for both); and ‘Calories and Sodium in Traffic Lights + CS’ (−29·1 calories, −58·6 mg sodium, P < 0·05 for both). Parents exposed to menus with ‘Calories, Sodium + CS’ and ‘Calories and Sodium in Traffic Lights + CS’ were more likely to notice and understand nutrition information compared to other nuntrition labelling conditions. Parents perceived the menu with ‘Calories and Sodium in Traffic Lights + CS’ as most effective (P < 0·05).
Menus disclosing calories, sodium and a contextual statement increased the proportion of parents who noticed and understood nutrition information, and resulted in parents selecting lower calorie and sodium entrées for their children in the hypothetical purchase task.
Dietary indices are widely used in diet quality measurement, and the index-based dietary patterns are related to gastric cancer risk. To evaluate the relationship between different kinds of index-based dietary patterns and gastric cancer risk, we systematically searched four English-language databases and four Chinese-language databases. The quality of studies was assessed by the Newcastle–Ottawa Scale. Meta-analyses were performed to estimate the association between gastric cancer incidence and different types of index-based dietary patterns. The OR and hazard ratios (HR) of gastric cancer incidence were calculated by regression models in case–control studies and prospective cohort studies, respectively. The studies were pooled in the random effects model to calculate the summarised risk estimate of the highest quantile interval of dietary indices, taking the lowest as the referent. The dietary indices included different versions of Mediterranean diet score (MDS) and dietary inflammatory index (DII), healthy eating index, Chinese Food Pagoda score and food index score. The meta-analysis was carried out for studies on MDS and DII. The combined OR of gastric cancer for the highest MDS v. the referent was 0·42 (95 % CI 0·2, 0·86), and the combined HR was 0·89 (95 % CI 0·68, 1·17). The combined OR for DII was 2·11 (95 % CI 1·41, 3·15). Higher Mediterranean dietary pattern consumption might reduce gastric cancer risk, while higher inflammatory diet pattern consumption might increase gastric cancer risk.
Konjac glucomannan (KGM) is a viscous dietary fibre that can form a solid, low-energy gel when hydrated and is commonly consumed in a noodle form (KGM-gel). Increased meal viscosity from gel-forming fibres have been associated with prolonged satiety, but no studies to date have evaluated this effect with KGM-gel. Thus, our objective was to evaluate subsequent food intake and satiety of KGM-gel noodles when replacing a high-carbohydrate preload, in a dose–response manner. Utilising a randomised, controlled, cross-over design, sixteen healthy individuals (twelve females/four males; age: 26·0 (sd 11·8) years; BMI: 23·1 (sd 3·2) kg/m2) received 325 ml volume-matched preloads of three KGM-gel noodle substitution levels: (i) all pasta with no KGM-gel (1849 kJ (442 kcal), control), half pasta and half KGM-gel (1084 kJ (259 kcal), 50-KGM) or no pasta and all KGM-gel (322 kJ (77 kcal), 100-KGM). Satiety was assessed over 90 min followed by an ad libitum dessert. Compared with control, cumulative energy intake was 47 % (−1761 kJ (−421 kcal)) and 23 % (−841 kJ (−201 kcal)) lower for 100-KGM and 50-KGM, respectively (both P<0·001), but no differences in subsequent energy intake was observed. Ratings of hunger were 31 % higher (P=0·03) for 100-KGM when compared with control, and were 19 % lower (P=0·04) for fullness and 28 % higher (P=0·04) for prospective consumption when comparing 100-KGM to 50-KGM. Palatability was similar across all treatments. Replacement of a high-carbohydrate preload with low-energy KGM-gel noodles did not promote additional food intake despite large differences in energy. The energy deficit incurred from partial KGM-gel substitution may have relevance in weight loss regimens, and should be further evaluated beyond the healthy population.
Oats are a rich source of β-glucan, a viscous, soluble fibre recognised for its cholesterol-lowering properties, and are associated with reduced risk of CVD. Our objective was to conduct a systematic review and meta-analysis of randomised-controlled trials (RCT) investigating the cholesterol-lowering potential of oat β-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for the risk reduction of CVD. MEDLINE, Embase, CINAHL and Cochrane CENTRAL were searched. We included RCT of ≥3 weeks of follow-up, assessing the effect of diets enriched with oat β-glucan compared with controlled diets on LDL-cholesterol, non-HDL-cholesterol or apoB. Two independent reviewers extracted data and assessed study quality and risk of bias. Data were pooled using the generic inverse-variance method with random effects models and expressed as mean differences with 95 % CI. Heterogeneity was assessed by the Cochran’s Q statistic and quantified by the I2-statistic. In total, fifty-eight trials (n 3974) were included. A median dose of 3·5 g/d of oat β-glucan significantly lowered LDL-cholesterol (−0·19; 95 % CI −0·23, −0·14 mmol/l, P<0·00001), non-HDL-cholesterol (−0·20; 95 % CI −0·26, −0·15 mmol/l, P<0·00001) and apoB (−0·03; 95 % CI −0·05, −0·02 g/l, P<0·0001) compared with control interventions. There was evidence for considerable unexplained heterogeneity in the analysis of LDL-cholesterol (I2=79 %) and non-HDL-cholesterol (I2=99 %). Pooled analyses showed that oat β-glucan has a lowering effect on LDL-cholesterol, non-HDL-cholesterol and apoB. Inclusion of oat-containing foods may be a strategy for achieving targets in CVD reduction.
We tested four predictions based on the assumption that optional infinitives can be attributed to properties of the input whereby children inappropriately extract non-finite subject–verb sequences (e.g. the girl run) from larger input utterances (e.g. Does the girl run? Let's watch the girl run). Thirty children with specific language impairment (SLI) and thirty typically developing children heard novel and familiar verbs that appeared exclusively either in utterances containing non-finite subject–verb sequences or in simple sentences with the verb inflected for third person singular -s. Subsequent testing showed strong input effects, especially for the SLI group. The results provide support for input-based factors as significant contributors not only to the optional infinitive period in typical development, but also to the especially protracted optional infinitive period seen in SLI.
A review of recently published temporal data from Shuidonggou Locality 1 indicates that a 40–43 cal ka date for the inception of Initial Upper Paleolithic (IUP) blade-oriented technologies in East Asia is warranted. Comparison of the dates from Shuidonggou to other Asian IUP dates in Korea, Siberia, and Mongolia supports this assertion, indicating that the initial appearance of the IUP in East Asia generally corresponds in time to the fluorescence of the IUP in eastern Europe and western Asia. This conclusion preliminarily suggests that either a version of the IUP originated independently in East Asia just prior to 40 cal ka, or more likely, that an early, initial diffusion of the IUP into East Asia occurred ∼41 cal ka, a hypothesis consistent with current estimates for the evolution or arrival of modern humans in the region.
We present results from preliminary analysis of radio interferometric data taken from the US Naval Observatory Radio Reference Frame Image Database. The results presented here reveal valuable insight into the structural variability of the two extragalactic radio sources 0552+398 and 1308+326. We are actively pursuing analysis of additional objects.
Fibre has been shown to exert a number of benefits on gastrointestinal (GI) health, yet its intake is low. Addition of novel fibres to food products may increase fibre intake and improve gut health. The objective of the present study was to evaluate the influence of three novel fibres on GI outcomes in healthy human subjects. A total of twenty healthy participants (ten men and ten women) with normal BMI (23 (sem 2) kg/m2) participated in the present randomised, double-blind, cross-over study with five treatment periods. Participants consumed a maltodextrin control or 20–25 g/d fibre from soluble maize fibre (SCF) or resistant starch (RS), alone or in combination with pullulan (SCF+P and RS+P). The treatment periods were 7 d with a 3-week washout between the periods. Stool samples were collected on day 7 of each period, and GI tolerance was assessed via a questionnaire on days 1 and 6. There were no treatment differences in stool weight or consistency. SCF significantly reduced stool pH and increased total SCFA production compared with RS and control. RS+P significantly increased the percentage of butyrate compared with all the other treatments. Overall, GI symptoms were minimal. SCF+P led to the highest GI score on day 1, while RS+P had the highest score on day 6. Both SCF treatments caused a significant shift in the gut microbial community. These functional fibres are generally well tolerated, have minimal effects on laxation and may lead to beneficial changes in SCFA production in healthy adults.
Chemical solution deposition techniques are a very competitive low cost method to achieve coated conductors. Recently, fluorine-free CSD methods have made a great progress for the preparation of YBCO thin films and became a sustainable alternative for the well-known trifluoroacetate CSD approach. By elucidating the reaction mechanism behind this new approach, finally giving an answer to the question why it is possible to fabricate YBCO films without TFA, different processing routes were discovered giving rise to high superconducting YBCO films (>1MA.cm-2). Each route has it's own benefits. One specific route offers the opportunity to tune the crystallographic orientation. By changing one process parameter, a shift from complete c-axis to complete a-axis orientation is observed. This can be very useful for e.g. Josephson Junctions.
We particularly investigated the fundamental reaction mechanism of each reaction route, with the focus on the corresponding barium compound. Although good superconducting properties are obtained, still one major drawback limits industrial implementation: thickness. It is observed that a critical thickness of ∼500 nm eliminates the superconducting properties. Therefore, this paper gives a summary of all progress made regarding to fluorine-free water-based CSD YBCO thin films with emphasis on the possibility to control the crystallization rate.
Protein synthesis, or translation, is an inherently dynamic process in which the ribosome traverses the open reading frame of a messenger RNA (mRNA) template in steps of precisely one triplet-nucleotide codon, catalyzing the selection of aminoacyl-transfer RNA (aa-tRNA) substrates and polymerization of the nascent polypeptide chain, while simultaneously coordinating the sequential binding of exogenous translation factors. The complexity of this process is mirrored by the intricate molecular architecture of the ribosome itself, highlighted in atomic detail by recent X-ray crystallographic structures that reveal an elaborate network of RNA-RNA, RNA-protein, and protein-protein interactions (Korostelev and Noller, 2007; Steitz, 2008). This high degree of intra- and inter-molecular connectivity suggests that allosteric mechanisms may regulate the activity and coordinate the timing of biochemical events catalyzed by spatially distal ribosomal functional centers. Large-scale conformational dynamics of the ribosome have similarly been implicated as a means by which to regulate the biochemical steps of protein synthesis and to power forward progression through the kinetic steps of the translation process.
Comparison of X-ray crystallographic structures of ribosomal subunits as well as the intact ribosome in the absence and presence of translation factors (reviewed in Schmeing and Ramakrishnan ), together with the analysis of cryogenic electron microscopy (cryo-EM) reconstructions of the ribosome trapped at various functional states during protein synthesis (see Chapter 7), has allowed visualization of large-scale conformational rearrangements of the translational machinery. Through such comparative structural analysis, mobile ribosomal domains have been identified and specific conformational changes have been inferred. However, these static structural images lack information regarding the timescales of the inferred conformational changes, and the kinetic and thermodynamic parameters underlying the corresponding ribosomal motions. Such dynamic information has recently been uncovered through the application of single-molecule fluorescence resonance energy transfer (smFRET) to studies of protein synthesis. This technique has proven to be particularly well-suited for monitoring and characterizing large-scale conformational dynamics of the ribosome and its tRNA and translation factor ligands, which often occur on length scales (∼tens of Ǻ) and time scales (∼ms to s) that are well matched with the spatio-temporal resolution of current smFRET methodologies (see Chapter 1). Guided by the structural data, numerous donor-acceptor fluorophore labeling schemes have already been developed, each capable of monitoring specific conformational changes of the translational machinery in real time.
Molecular dynamic simulations of helium atoms escaping from a helium-filled nanobubble near the surface of crystalline palladium reveal unexpected behavior. Significant deformation and cracking near the helium bubble occur initially, and then a channel forms between the bubble and the surface, providing a pathway for helium atoms to propagate toward the surface. The helium atoms erupt from the bubble in an instantaneous and volcano-like process, which leads to surface deformation consisting of cavity formation on the surface, along with modification and atomic rearrangement at the periphery of the cavity. The present simulation results show that, near the palladium surface, there is a helium-bubble-free zone, or denuded zone, with a typical thickness of about 3.0 nm. Combined with experimental measurements and continuum-scale evolutionary model predictions, the present atomic simulations demonstrate that the thickness of the denuded zone, which contains a low concentration of helium atoms, is somewhat larger than the diameter of the helium bubbles in the metal tritide. Furthermore, a relationship between the tensile strength and thickness of metal film is also determined.
The U.S. military uses large amounts of fuel during deployments and battlefield operations. Consequently, the U.S. military has a strong need to develop technologies that increase fuel efficiency and minimize fuel requirements all along the logistics trail and in all battlefield operations. There are additional requirements to reduce and minimize the environmental footprint of various military equipment and operations and reduce the need for batteries (non-rechargeable) in battlefield operations. The tri-agency SERDP (Strategic Environmental Research and Development Program) office is sponsoring a challenging, high-payoff project to develop a lightweight, small form-factor, soldier-portable advanced thermoelectric generator (TEG) system prototype to recover and convert waste heat from a variety of deployed equipment with the ultimate purpose of obtaining additional power for soldier battery charging, advanced capacitor charging, and other battlefield power applications. The project seeks to achieve power conversion efficiencies of 10% (double current commercial TE conversion efficiencies) in a system with ˜1.6-kW power output for a spectrum of battlefield power applications. In order to meet this objective, the project is taking on the multi-faceted challenges of tailoring LAST/LASTT-based thermoelectric (TE) materials for the proper temperature ranges (300 K – 700 K), fabricating these materials with cost-effective hot-pressed and sintered processes while maintaining their TE properties, measuring and characterizing their thermal fatigue and structural properties, developing the proper manufacturing processes for the TE materials and modules, designing and fabricating the necessary microtechnology heat exchangers, and fabricating and testing the final TEG system. The ultimate goal is to provide an opportunity to deploy these TEG systems in a wide variety of current military equipment. This would help the Army in achieving one of the Office of Secretary of Defense’s major strategic objectives to maintain and enhance operational effectiveness while reducing total force energy demands. The presentation will review the progress made on 1) the performance of LAST / LASTT TE materials and tailoring their temperature dependency; 2) evaluating the structural (Elastic modulus, Poisson’s ratio and mechanical strength) properties of these materials, 3) development of the necessary LAST/LASTT-based TE modules, 4) development of the required hot- and cold-side microtechnology heat exchangers, and 5) the overall system designs for 30 kW and 60 kW TQG applications and potential performance pathways/differences for these two TQG cases. This work leverages critical fundamental research performed by the Office of Naval Research in developing LAST/LASTT materials.
Copper aluminum oxide (CuAlO2) with delafossite structure is a promising candidate for high temperature thermoelectric applications because of its modest band gap, high stability and low cost. We investigate magnesium doping on the aluminum site as a means of producing higher electrical conductivity and optimized Seebeck coefficient. Powder samples were synthesized using solid-state reaction and bulk samples were prepared using both cold-pressing and hot-pressing techniques. Composition analysis, microstructural examination and transport property measurements were performed, and the results suggest that while hot-pressing can achieve high density samples, secondary phases tend to form and lower the performance of the materials.
Tensile deformation of individual electrospun polyvinyl alcohol (PVA) nanofibres was performed using a novel combination atomic force microscope (AFM)- scanning electron microscope (SEM) technique. The AFM was used to provide manipulation and mechanical testing of individual PVA nanofibers while the SEM was used to observe the deformation process. Resultant stress-strain curves show how the elastic modulus shows comparable, or even slightly increased, values to isotropic films. In addition, the electrospun fibers were tested to failure to measure their tensile strength.
A technique combining both atomic force microscopy (AFM) and scanning electron microscopy (SEM) is used to evaluate the mechanical properties of individual collagen fibrils from the fractured surface of antler. SEM is used to locate individual mineralized collagen fibrils and allow visualization of the attachment of these fibrils to the end of an AFM probe. Tensile testing of individual collagen fibril to failure was performed using the AFM with resultant stress-strain curves obtained. Tensile strengths of up to 0.18GPa are found for some individual collagen fibrils, indicating the presence of mineral in improving mechanical performance. Consideration of the SEM operating parameters indicates that the amount of time the sample is within the SEM vacuum can affect the resultant mechanical behavior of individual fibrils.