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Saetaspongia so far cannot be confidently assigned to any class-level crown group. Clarifying its phylogenetic position requires new information provided by more detailed studies of previously described and/or new material. Some sponge fossils with the typical skeletal architecture of Saetaspongia have recently been recognized in the Cambrian (Stage 4) Balang Biota of Guizhou, China, including S. jianhensis new species and S. cf. S. densa. The new taxon is characterized by the following features: spicules are fine monaxons and are inclined to be loosely to densely arranged into plumose arrays; skeleton is composed primarily of one major plumose bundle, with an uncertain number (perhaps two) of small plumose arrays; and primary skeleton is occasionally interspersed with some irregularly oriented individual spicules. An additional specimen consisting of large monaxons, with plumose structures and overlying irregular coarse monaxons, closely fits the description and illustrations of previously described S. cf. S. densa. By combining information from previous studies and the present research, fossil evidence indicates that the plumose architecture is a critical feature diagnostic of Saetaspongia and that there are no hexactine-based spicules in this genus. The new material from the Balang Biota further supports the notion that Saetaspongia has a protomonaxonid rather than a hexactinellid affinity. Fossil evidence suggests that Saetaspongia had a wide biogeographic distribution during the early Cambrian and the stratigraphic distribution of this genus extends up to Stage 4.
Precise auditory perception at a subcortical level (neural representation and encoding of sound) has been suggested as a form of implicit L2 aptitude in naturalistic settings. Emerging evidence suggests that such implicit aptitude explains some variance in L2 speech perception and production among adult learners with different first language backgrounds and immersion experience. By examining 46 Chinese learners of English, the current study longitudinally investigated the extent to which explicit and implicit auditory processing ability could predict L2 segmental and prosody acquisition over a 5-month early immersion. According to the results, participants’ L2 gains were associated with more explicit and integrative auditory processing ability (remembering and reproducing music sequences), while the role of implicit, preconscious perception appeared to be negligible at the initial stage of postpubertal L2 speech learning.
Seaweeds have numerous biologically active ingredients, such as polysaccharides, polyphenols and carotenoids, that are beneficial to human health. Although these benefits might be related to the synthesis, secretion or reabsorption of uric acid, no studies have explored the relationship between seaweeds consumption and hyperuricaemia (HUA) in the general population. The aim of this study was to investigate whether seaweeds consumption is related to HUA in a large-scale adult population. A cross-sectional study was conducted with 32 365 adults (17 328 men and 15 037 women) in Tianjin, People’s Republic of China. Frequency of seaweeds consumption was assessed by a validated self-administered FFQ. HUA was defined as serum uric acid levels >420 μmol/L in men and >350 μmol/L in women. The association between seaweeds consumption and HUA was assessed by multiple logistic regression analysis. Restricted cubic spline functions were used for non-linearity tests. The prevalence of HUA in men and women was 21·17 % and 5·93 %, respectively. After adjustments for potential confounding factors, the OR (95 % CI) for HUA across seaweed consumption (g/1000 kcal per d) were 1·00 (reference) for level 1, 0·91 (95 % CI 0·81, 1·02) for level 2; 0·90 (95 % CI 0·81, 1·01) for level 3; 0·86 (95 % CI 0·78, 0·97) for level 4 in men and 0·90 (95 % CI 0·73, 1·10) for level 2; 0·82 (95 % CI 0·67, 1·00) for level 3; 0·84 (95 % CI 0·68, 1·03) for level 4 in women, respectively. A negative correlation between seaweeds consumption and HUA in males but not in females was observed. Further studies are needed to explore the causal relationship.
To investigate the clinical impact of ventilator-associated events (VAEs) on adverse prognoses and risk factors for mortality among intensive care unit (ICU) patients receiving invasive mechanical ventilation (IMV) based on an ICU healthcare-associated infection (ICU-HAI) registry.
A cohort study was conducted based on an ICU-HAI registry including 30,830 patients between 2015 and 2018.
The study was conducted using data from 5 adult ICUs of a referral hospital.
Adult patients in the ICU-HAI registry who received ≥4 consecutive IMV days.
Clinical outcomes and mortality risk factors for VAEs were analyzed using propensity score matching (PSM), multivariate regression models, and sensitivity analyses.
Of 6,426 included patients, 1,803 developed 1,899 VAEs. After PSM, patients with VAEs did have prolonged length of stay in the ICU and in the hospital, increased hospitalization costs, longer days on mechanical ventilation, higher proportion of ≥9 days on mechanical ventilation, higher rate of failure in extubating mechanical ventilation, and excess all-cause mortality in the ICU. Older age (adjusted OR [aOR], 1.02), higher APACHE II score on ICU admission (aOR, 1.06), pneumonia (aOR, 1.49), blood transfusion (aOR 1.43), immunosuppressive drugs (aOR, 1.69), central-line catheter (aOR, 2.06), and ≥2 VAEs in the ICU (aOR, 1.99) were associated with higher risks for all-cause mortality in an ICU.
Patients with VAEs indeed had poorer clinical outcomes. Older age, higher APACHE II score on ICU admission, pneumonia, blood transfusion, immunosuppressive drugs, central-line catheter, and ≥2 VAEs in the ICU were risk factors for all-cause mortality of VAE patients in the ICU.
A fever clinic within a hospital plays a vital role in pandemic control because it serves as an outpost for pandemic discovery, monitoring and handling. As the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan was gradually brought under control, the fever clinic in the West Campus of Wuhan Union Hospital introduced a new model for construction and management of temporary mobile isolation wards. A traditional battlefield hospital model was combined with pandemic control regulations, to build a complex of mobile isolation wards that used adaptive design and construction for medical operational, medical waste management and water drainage systems. The mobile isolation wards allowed for the sharing of medical resources with the fever clinic. This increased the capacity and efficiency of receiving, screening, triaging and isolation and observation of patients with fever. The innovative mobile isolation wards also controlled new sudden outbreaks of COVID-19. We document the adaptive design and construction model of the novel complex of mobile isolation wards and explain its characteristics, functions and use.
In this study, we propose a hypothesis that domain-general auditory processing, a perceptual anchor of L1 acquisition, can serve as the foundation of successful post-pubertal L2 learning. This hypothesis was tested with 139 post-pubertal L2 immersion learners by linking individual differences in auditory discrimination across multiple acoustic dimensions to the segmental, prosodic, lexical, and morphosyntactic dimensions of L2 proficiency. Overall, auditory processing was a primary determinant of a range of participants’ proficiency scores, even after biographical factors (experience, age) were controlled for. The link between audition and proficiency was especially clear for L2 learners who had passed beyond the initial phase of immersion (length of residence > 1 year). The findings suggest that greater auditory processing skill benefits post-pubertal L2 learners immersed in naturalistic settings for a sufficient period of time by allowing them to better utilize received input, which results in greater language gains and leads to more advanced L2 proficiency in the long run (similar to L1 acquisition).
A series of new synthetic armored cables were developed and tested to ensure that they were suitable for use with the RECoverable Autonomous Sonde (RECAS), which is a newly designed freezing-in thermal ice probe. The final version of the cable consists of two concentric conductors that can be used as the power and signal lines. Two polyfluoroalkoxy jackets are used for electrical insulation (one for insulation between conductors, and the other for insulation of the outer conductor). The outer insulation layer is coated by polyurethane jacket to seal the connections between the cable and electrical units. The 0.65 mm thick strength member is made from aramid fibers woven together. To hold these aramid fibers in place, a sheathing layer was produced from a polyamide fabric cover net. The outer diameter of the final version of the cable is ~6.1 mm. The permissible bending radius is as low as 17–20 mm. The maximal breaking force under straight tension is ~12.2 kN. The cable weight is only ~0.061 kg m−1. The mechanical and electrical properties and environmental suitability of the cable were determined through laboratory testing and joint testing with the probe.
To examine the association between physician–patient treatments shared decision making (SDM), patient satisfaction, and adoption of a new health technology.
A cross-sectional study was conducted from July 2016 to October 2016 in Fujian Province and Shanghai, in Eastern China. A total of 542 physicians and 619 patients in eleven hospitals were surveyed. Patients and their treating physicians completed self-reported questionnaires on patient–physician SDM, satisfaction with treatment decision making and adoption of a new health technology. Correlation analysis, multivariate logistic regression and multivariate linear regression were performed.
The majority (68.20 percent) of patients preferred SDM. Involvement of patients in SDM was positively associated with their satisfaction with treatment decision making (p < .001) and adoption of a new health technology (p < .05). Better concordance between their preference and actual SDM was positively associated with patients' adoption behavior (p < .05), but no statistically significant association was found between concordance and satisfaction.
SDM was the most important predictor of patients' satisfaction with decision making and adoption of a new health technology. Therefore, better communication between physicians and patients is recommended to improve their SDM, increase patient satisfaction and to assist with the adoption of new technologies. Training healthcare provider and teaching communication skills in working with patients in the initial stage of technology diffusion is required.
The Yangtze Block in South China constitutes an important Precambrian landmass in the present East Asian continent. The Neoproterozoic sedimentary successions of the Hengdan Group in the NW Yangtze Block record essential information for deciphering the Neoproterozoic tectonics along the NW margin. However, its depositional age, provenance and tectonic properties remain uncertain. Here, a combined analysis of detrital zircon U–Pb dating and geochemistry is performed on representative samples from the Hengdan Group. Concordant dating results of samples from the bottom and upper parts constrain the maximum depositional age at c. 720 Ma. Detrital zircon age patterns of samples reveal a uniformly pronounced age peak at c. 915–720 Ma, which is consistent with the magmatic pulses in domains at the NW end of the Yangtze Block. In addition, these samples display left-sloping post-Archaean Australian shale (PAAS)-normalized rare-earth element patterns and variable trace element patterns, resembling sediments accumulated in a basin related to an active continental margin geodynamic setting. Provenance analysis reveals that the main sources featured intermediate to felsic components, which experienced rapid erosion and sedimentation. These integrated new investigations, along with previous compilations, indicate that the Hengdan Group might have been deposited in a fore-arc basin controlled by subduction beneath the Bikou Terrane. Thus, such interpretation further supports proposals for subduction-related tectonics along the western margin of the Yangtze Block during the early Neoproterozoic.
In this study, we propose a hypothesis that domain-general auditory processing, a perceptual–cognitive anchor of first language (L1) acquisition, can serve as an important deciding factor for successful postpubertal second language (L2) pronunciation learning. To examine this hypothesis, samples of spontaneous speech were elicited from a total of 30 L1 Chinese L2 English learners at two points (outset and endpoint) during an 8-month study-abroad period in the United Kingdom. The participants were tested on three different components of auditory processing ability (formant, pitch, and duration discrimination) using behavioral instruments. The auditory processing scores were then linked to the segmental, prosodic, and fluency dimensions of their L2 pronunciation proficiency development throughout the project. Overall, most learners’ speech became smoother, faster, and more fluent (fewer pauses, faster articulation rate, and more optimal perceived tempo). Certain learners with high-level auditory processing ability (more precise formant discrimination) appeared to further attain more correct pronunciation of individual sounds and words (greater segmental and word stress accuracy), leading to more advanced L2 phonological skills (fluent and accurate). The findings suggest that auditory processing abilities can be a root of language learning throughout the life span and may apply to the initial- to midphase of naturalistic L2 pronunciation learning in adulthood.
This study aimed to identify clinical features for prognosing mortality risk using machine-learning methods in patients with coronavirus disease 2019 (COVID-19). A retrospective study of the inpatients with COVID-19 admitted from 15 January to 15 March 2020 in Wuhan is reported. The data of symptoms, comorbidity, demographic, vital sign, CT scans results and laboratory test results on admission were collected. Machine-learning methods (Random Forest and XGboost) were used to rank clinical features for mortality risk. Multivariate logistic regression models were applied to identify clinical features with statistical significance. The predictors of mortality were lactate dehydrogenase (LDH), C-reactive protein (CRP) and age based on 500 bootstrapped samples. A multivariate logistic regression model was formed to predict mortality 292 in-sample patients with area under the receiver operating characteristics (AUROC) of 0.9521, which was better than CURB-65 (AUROC of 0.8501) and the machine-learning-based model (AUROC of 0.4530). An out-sample data set of 13 patients was further tested to show our model (AUROC of 0.6061) was also better than CURB-65 (AUROC of 0.4608) and the machine-learning-based model (AUROC of 0.2292). LDH, CRP and age can be used to identify severe patients with COVID-19 on hospital admission.
Non-alcoholic fatty liver disease (NAFLD) has become the main cause of end-stage liver disease. Probiotics have the potential effect of alleviating NAFLD. The aim of this study was to explore functional probiotics and their underlying mechanisms. The bile salt hydrolase (BSH) activity in thirty-four strains was determined in vitro. Then, C57BL/6 mice were used to explore the effects of probiotics on NAFLD. Body weight and food intake were measured, and serum lipid concentrations, oxidative stress and proinflammatory cytokines levels were determined using commercial kits. The expressions of intestinal bile acid pathway genes were evaluated via real-time PCR. The results showed that Lactobacillus casei YRL577 and L. paracasei X11 had higher BSH activity. L. casei YRL577 significantly reduced liver weight and liver index and could regulate the levels of lipid metabolism, oxidative stress and proinflammatory cytokines as compared with L. paracasei X11. Furthermore, the results indicated that L. casei YRL577 up-regulated the mRNA levels of farnesoid X receptor and fibroblast growth factor 15, whereas down-regulated the mRNA level of apical Na-dependent bile acid transporter. These findings suggested that L. casei YRL577 modified genes in the intestinal bile acid pathway which might contribute to the alleviation of NAFLD.
β-Glucan has been reported for its health benefits on blood lipids in hypercholesterolaemic individuals for years. However, people have paid little attention to the effects of β-glucan in populations with mild hypercholesterolaemia as well as the various delivering matrices. Our objective was to perform a meta-analysis to analyse the effects of β-glucan with different delivering matrices in mildly hypercholesterolaemic individuals. After conducting a comprehensive search in Web of Science, PubMed, Scopus and Cochrane Library, a total of twenty-one randomised controlled trials involving 1120 participants were identified to measure the pooled effect. The overall results indicated that consuming a dose of ≥3 g/d of β-glucan for at least 3 weeks could significantly reduce total cholesterol (TC) (−0·27 mmol/l, 95 % CI −0·33, −0·21, P < 0·001) and LDL-cholesterol (−0·26 mmol/l, 95% CI −0·32, −0·20, P < 0·001) compared with the control group in mildly hypercholesterolaemic individuals, while no significant difference was observed in TAG (−0·03 mmol/l, 95% CI −0·11, 0·06, P = 0·521) and HDL-cholesterol (0·01 mmol/l, 95% CI −0·03, 0·04, P = 0·777). There was evidence for modest unexplained heterogeneity in the meta-analysis. In conclusion, β-glucan can significantly reduce risk factors like TC and LDL-cholesterol for CVD in mildly hypercholesterolaemic individuals; furthermore, it appears that the effects of food matrices with both ‘solid products’ and ‘liquid products’ where β-glucan was incorporated into were ranked as the best way to exert its beneficial properties, while ‘liquid’ and ‘solid’ products were ranked as the second and third positions, respectively.
Following the trends established in psychology and emerging in L2 research, we explain our support for an Open Science approach in this paper (i.e., developing, analyzing and sharing datasets) as a way to answer controversial and complex questions in applied linguistics. We illustrate this with a focus on a frequently debated question, what underlies individual differences in the dynamic system of post-pubertal L2 speech learning? We provide a detailed description of our dataset which consists of spontaneous speech samples, elicited from 110 late L2 speakers in the UK with diverse linguistic, experiential and sociopsychological backgrounds, rated by ten L1 English listeners for comprehensibility and nativelikeness. We explain how we examined the source of individual differences by linking different levels of L2 speech performance to a range of learner-extrinsic and intrinsic variables related to first language backgrounds, age, experience, motivation, awareness, and attitudes using a series of factor and Bayesian mixed-effects ordinal regression analyses. We conclude with a range of suggestions for the fields of applied linguistics and SLA, including the use of Bayesian methods in analyzing multivariate, multifactorial data of this kind, and advocating for publicly available datasets. In keeping with recommendations for increasing openness of the field, we invite readers to rethink and redo our analyses and interpretations from multiple angles by making our dataset and coding publicly available as part of our 40th anniversary ARAL article.
Wireless power transfer (WPT) has attracted attention from academia and industry in recent years. WPT has natural electrical isolation between primary and secondary side, which ensures safe charging in an underwater environment. This breakthrough technology greatly facilitates the deep-sea power transmission. However, at the current stage the transferred power and energy efficiency level are not up to that of the WPT system in the air. The major concerns include the attenuation is seawater, extreme temperature and pressure conditions, disturbance of ocean currents, and bio-security. Three questions are answered in this paper: first, the expressions of eddy current loss and attenuation of electromagnetic wave in seawater are unified, and the influence of seawater as transmission medium on the WPT system is discussed. Second, the evolution of electromagnetic coupling structure suitable for underwater applications is studied. Third, the loss and heating effects of an underwater WPT system and the corresponding bio-fouling phenomenon are investigated. The questions above were addressed through analysis of electrical properties, coupler structures, and bio-fouling effects of the underwater WPT system. This paper will facilitate the study and research on underwater WPT applications.
This mini review summarizes recent advances in experimental thermodynamics of metal–organic frameworks (MOFs). Taking advantage of the development in mechanochemistry, near-room temperature solution calorimetry, and low-temperature heat capacity measurements, the energetic landscape, entropy trends, and Gibbs free energy evolutions of MOFs with true polymorphism [Zn(MeIm)2, Zn(EtIm)2, and Zn(CF3Im)2] as framework topology varies were thoroughly explored by integrated calorimetric and computational methodologies. In addition, the formation enthalpies of MOFs with ultrahigh porosity (MOF-177 and UMCM-1) and the simplest structure (metal formates) have been determined. The studies summarized below highlight the complex interplays among interrelated compositional, chemical, and topological (structural) factors in the determination of the thermodynamic parameters of MOFs.
This article overviews the ultrasonic welding process, a solid-state joining method, using the example of welding of a magnesium alloy as well as the joining of magnesium alloys in general. In situ high-speed imaging and infrared thermography were utilized to study interfacial relative motion and heat generation during ultrasonic spot welding of AZ31B magnesium (Mg) alloys. A postweld ultrasonic nondestructive evaluation was performed to study the evolution of local bond formation at the faying interface (contact surface of the joint between the top and bottom Mg sheets) at different stages of the welding process. Two distinct stages were observed as the welding process progresses. In the early stage, localized reciprocating sliding occurred at the contact faying interface between the two Mg sheets, resulting in localized rapid temperature rise from the localized frictional heating. Microscale (submillimeter) bonded regions at the Mg–Mg faying surface started to form, but the overall joint strength was low. The early-stage localized bonds were broken during the subsequent vibrations. In the later stage, no relative motion occurred at any points of the faying interface. Localized bonded regions coalesced into a macroscale joint that was strong enough to prevent the Mg–Mg interface from further breakage and sliding. With increasing welding time, the bonded area continued to increase.
The current study examines how second language (L2) users differentially assess the comprehensibility (i.e., ease of understanding) of foreign-accented speech according to a range of background variables, including first language (L1) profiles, L2 proficiency, age, experience, familiarity, and metacognition. A total of 110 L2 listeners first evaluated the global comprehensibility of 50 spontaneous speech samples produced by low-, mid-, and high-proficiency Japanese speakers of English. The listeners were categorized into two subgroups according to a cluster analysis of their rating scores: lenient and strict. Results showed that while the lenient listeners appeared to rely equally on many linguistic areas of speech during their judgments, the strict listeners were strongly attuned to phonological accuracy. Analysis of the background questionnaire data revealed that more lenient listeners likely had higher levels of awareness of the importance of comprehensibility for communication (metacognition); regularly used L2 English in professional settings (experience); and had L1s more linguistically close to the target speech samples, Japanese-accented English (L1-L2 distance).
Nitrogen (N) inputs have been found to exert strong influence on leaf stoichiometry in natural ecosystems, but there are few studies investigating the effects of N in agroecosystems. Using a 5-yr fertilization experiment in rice fields, we examined the effects of N inputs on leaf stoichiometry of one crop, rice (Oryza sativa L.), and its four common weeds, barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.], Monochoria korsakowii Regel and Mack, alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.], and Japanese mazus [Mazus pumilus (Burm. f.) Steenis], and further evaluated whether and how straw return mediates these effects. We found that rice and weed leaf nitrogen:phosphorus:potassium (N:P:K) stoichiometry exhibited divergent responses to N fertilizer. Weed leaf N:P:K stoichiometry was not sensitive to low (120 kg N ha−1) and regular (240 kg N ha−1) N inputs, but rice plants were, with significantly increased leaf N concentration and N:P and N:K ratios. The opposite trend was found for high N inputs (360 kg N ha−1). Rice leaf N concentration [N] did not increase further, and N:P ratios even decreased, whereas E. crus-galli and M. korsakowii had significantly increased [N] and N-related stoichiometry. We also found that the positive effects of regular N inputs on rice leaf N:P and N:K ratios were significantly dampened by straw return, but the positive effects on N:P ratios in M. pumilus leaves were enhanced by straw return. Compared with weeds, rice leaves contained low elemental concentrations across fertilization levels at grain-filling stages. These results indicate that rice has a lower N requirement than weeds at grain-filling stages, and the N supply should be managed at a relative low level to reduce the nutrient acquisition and competitive abilities of weeds. From a stoichiometric perspective, this study highlights the importance of N management in combination with straw return in controlling weeds and increasing the nutrient-use efficiency of crops.