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The interaction between heavy particles with high Stokes number ($St$) and the wall, known as the particle–wall (P–W) process, widely exists in natural and engineering two-phase flows, whereas its effects on particle-laden flows and the large-scale/very large-scale turbulent motions (VLSM) remain unclear. In this paper, two types of wind-blown sand-laden flows were experimentally designed and investigated by keeping the same free stream velocity, flow Reynolds number and particle $St$ number. In the first type, sand particles were directly blown from a sand bed at the bottom wall of the wind tunnel, and the P–W process occurred in the whole wall-normal region of the sand-laden flow. In the second type, sand particles were released from a feeder at the top wall of wind tunnel, and the P–W process was only present in a lower wall-normal region. Simultaneous two-phase particle image/tracking velocimetry measurements were conducted for uncovering the characteristics of turbulent structures in the particle-laden turbulent boundary layers. The results confirmed that the VLSM with streamwise scales exceeding $3\delta$ ($\delta$ is boundary layer thickness) above a certain height exist in both types of the sand-laden flows and could be significantly affected by the P–W process. That is, in the region without the P–W process, the presence of sand particles can enlarge the VLSM, while in the region with the P–W process, the VLSM are substantially reduced in size or even destroyed. The reduction degree is found to be closely related to the strength of the P–W process.
We evaluate the association between the Dietary Inflammatory Index (DII) and kidney stones.
We performed a cross-sectional analysis using data from National Health and Nutrition Examination Survey. Dietary intake information was assessed using first 24-HR dietary recall interviews, and the Kidney Conditions was presented by questionnaire. The primary outcome was to investigate the association between DII and incidence of kidney stones, and the secondary outcome was to assess the association between DII and nephrolithiasis recurrence.
The National Health and Nutrition Examination Survey (NHANES), 2007-2016.
The study included 25984 NHANES participants, whose data on DII and kidney stones were available, of whom 2439 reported a history of kidney stones.
For the primary outcome, after fully multivariate adjustment, DII score is positively associated with the risk of kidney stones (OR = 1.07; 95% CI: [1.04–1.10]). Then, compared Q4 with Q1, a significant 38% increased likelihood of nephrolithiasis was observed. (OR=1.38; 95% CI: [1.19–1.60]). For the secondary outcome, the multivariate regression analysis showed that DII score is positively correlated with nephrolithiasis recurrence (OR=1.07; 95% CI: [1.00–1.15]). The results noted that higher DII scores (Q3 and Q4) are positively associated with a significant 48% and 61% increased risk of nephrolithiasis recurrence compared with the reference after fully multivariate adjustment. (OR=1.48; 95% CI: [1.07–2.05]; OR=1.61; 95% CI: [1.12–2.31]).
Our findings revealed that increased intake of pro-inflammatory diet, as a higher DII score, is correlated with increased odds of kidney stones incidence and recurrence.
In this paper, we report the study of degradation for a kind of ideal mandrel material called poly-α-methylstyrene based on theoretical and experimental methods. First-principles calculations reveal two types of process: depolymerization and hydrogen-transfer-induced chain scission. The energy barrier for the former (0.68–0.82 eV) is smaller than that for most of the latter (1.39–4.23 eV). More importantly, reaction rates suggest that the former is fast whereas the latter is mostly slow, which can result in a difference of 5–31 orders of magnitude at 550 K. Furthermore, a thermogravimetric experiment shows that the activation energy of 2.53 eV for degradation is between those of fast and slow processes, corresponding to the theoretical average value of multiple reaction paths. Thus, a mandrel degradation model combining fast and slow processes is established at the atomic level. Our work provides a direction for research into the key technology of target fabrication in inertial confinement fusion.
We report a case of a 25-year-old man diagnosed with an unusual case of cor triatriatum sinister with a mobile left atrial thrombus. He was hospitalised with aggravating dyspnoea. Transthoracic echocardiography revealed a membrane-like structure traversing the left atrial and a small orifice of about 7.1 mm. The mean pressure gradient was 12.94 mmHg across the orifice of the membrane-like structure and there was a mobile mass in the post-erosuperior chamber. The anomaly was rectified by a surgical resection. Timely diagnosis and surgical repair may prevent stroke in patients with unusual cor triatriatum sinister.
To determine if specific dietary patterns are associated with breast cancer risk in Chinese women.
Latent class analysis (LCA) was performed to identify generic dietary patterns based on daily food-frequency data.
The Chinese Wuxi Exposure and Breast Cancer Study (2013-2014).
A population-based case-control study (695 cases, 804 controls).
Four dietary patterns were identified, Prudent, Chinese traditional, Western, and Picky, the proportion in the controls and cases were 0.30/0.32/0.16/0.23 and 0.29/0.26/0.11/0.33, respectively. Women in Picky class were characterized by higher extreme probabilities of non-consumption on specific foods, the highest probabilities of consumption of pickled foods, and the lowest probabilities of consumption of cereals, soy foods, and nuts. Compared with Prudent class, Picky class was associated with a higher risk (OR=1.42, 95%CI=1.06, 1.90), while the relevant association was only in post- (OR=1.44, 95%CI=1.01, 2.05) but not premenopausal women. The Western class characterized by high-protein, -fat, and -sugar foods, the Chinese traditional class characterized by typical consumption of soy foods and white meat over red meat, both of them showed no difference in BC risk compared with Prudent class did.
LCA capture the heterogeneity of individuals embedded in the population, could be a useful approach in the study of dietary pattern and disease. Our results indicated that the Picky class might have a positive association with the risk of breast cancer.
Drug-induced liver injury (DILI) is a common adverse drug reaction leading to the interruption of tuberculosis (TB) therapy. We aimed to identify whether the hepatitis B virus (HBV) infection would increase the risk of DILI during first-line TB treatment. A meta-analysis of cohort studies searched in PubMed, Web of Science and China National Knowledge Infrastructure was conducted. Effect sizes were reported as risk ratios (RRs) and 95% confidence intervals (CIs) and calculated by R software. Sixteen studies with 3960 TB patients were eligible for analysis. The risk of DILI appeared to be higher in TB patients co-infected with HBV (RR 2.66; 95% CI 2.13–3.32) than those without HBV infection. Moreover, patients with positive hepatitis B e antigen (HBeAg) were more likely to develop DILI (RR 3.42; 95% CI 1.95–5.98) compared to those with negative HBeAg (RR 2.30; 95% CI 1.66–3.18). Co-infection with HBV was not associated with a higher rate of anti-TB DILI in latent TB patients (RR 4.48; 95% CI 0.80–24.99). The effect of HBV infection on aggravating anti-TB DILI was independent of study participants, whether they were newly diagnosed with TB or not. Besides, TB and HBV co-infection patients had a longer duration of recovery from DILI compared to non-co-infected patients (SMD 2.26; 95% CI 1.87–2.66). To conclude, the results demonstrate that HBV infection would increase the risk of DILI during TB therapy, especially in patients with positive HBeAg, and close liver function monitoring is needed for TB and HBV co-infection patients.
Lead-free ferroelectric electrocaloric ceramics that could convert electrical energy into heat are the promising candidate for environment-friendly cooling devices. For refrigeration devices, a large temperature change (ΔT) and good temperature stability are required, which are highly related to the phase structure and the applied electric field. In this work, a diffused ferroelectric–paraelectric (FP) phase transition is formed in (K, Na)NbO3 (KNN) by using appropriate composition engineering. The relaxor ferroelectrics in this work present both a large ΔT of 1.24 K and a high ΔT/ΔE of 0.19 K mm/kV. In addition, a wide temperature span exceeds 55 °C at the high electrocaloric effect (ECE) criterion (ΔT ≥ 0.5 K) could also be observed. This work not only opens a new strategy for obtaining high-performance ceramics for refrigeration devices but also extends the application area of the KNN-based lead-free ferroelectrics from sensors, actuators and energy harvesting to solid-state cooling applications.
The phylogeny of foliicolous taxa in Pilocarpaceae was reconstructed using Bayesian and maximum likelihood analyses of concatenated ITS and mtSSU sequences. Sixty-six new partial sequences representing 36 taxa were generated and 29 sequences were downloaded from GenBank. Our results indicate that Lasioloma R. Sant. is nested within a paraphyletic Calopadia Vězda, whereas Fellhanera Vězda is polyphyletic and the phylogenetic relationships of Eugeniella Lücking et al. and Sporopodium Mont. with Fellhanera require further investigation. In addition, Tapellaria parvimuriformis W. C. Wang & J. C. Wei is described as a new species from Khao Yai National Park, Thailand, and is characterized by its small muriform ascospores, grey campylidia with a pale base, and short conidia. Eight new records of foliicolous lichens for Thailand are also listed.
No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment.
This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance.
Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6).
Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.
Parabronema skrjabini is one of the most harmful nematodes to camels and is responsible for economic losses in animal husbandry industry. There is an urgent need for in-depth studies of potential vectors of the nematode due to its scant regarding information. As previous studies indicated that flies may be the vectors of P. skrjabini, we captured flies in the main camel-producing areas of Inner Mongolia. After autopsy of the specimens of two species of horn flies, we observed the morphology of the suspected nematode larvae found in them. Internal transcribed spacer ribosomal-DNA gene sequences were considered the best candidate to confirm the species of the larvae found. Our results showed that the homology compared with P. skrjabini was 99.5% in GenBank. Subsequently, we preliminarily identified two species of horn flies through morphological observation and then sequenced the mitochondrial-DNA-gene cytochrome oxidase subunit I obtained from two species of horn flies, with 100 and 99.2% similarity to sequences deposited in GenBank, respectively. Thus, we identified Haematobia titillans and Haematobia irritans and provided evidence for their potential role as vectors of parabronemosis. Our study provides reference for future research on the life history of the nematode and the vectors of parabronemosis.
Diet has direct and indirect effects on health through inflammation and the gut microbiome. We investigated total dietary inflammatory potential via the literature-derived index (Dietary Inflammatory Index (DII®)) with gut microbiota diversity, composition and function. In cancer-free patient volunteers initially approached at colonoscopy and healthy volunteers recruited from the medical centre community, we assessed 16S ribosomal DNA in all subjects who provided dietary assessments and stool samples (n 101) and the gut metagenome in a subset of patients with residual fasting blood samples (n 34). Associations of energy-adjusted DII scores with microbial diversity and composition were examined using linear regression, permutational multivariate ANOVA and linear discriminant analysis. Spearman correlation was used to evaluate associations of species and pathways with DII and circulating inflammatory markers. Across DII levels, α- and β-diversity did not significantly differ; however, Ruminococcus torques, Eubacterium nodatum, Acidaminococcus intestini and Clostridium leptum were more abundant in the most pro-inflammatory diet group, while Akkermansia muciniphila was enriched in the most anti-inflammatory diet group. With adjustment for age and BMI, R. torques, E. nodatum and A. intestini remained significantly associated with a more pro-inflammatory diet. In the metagenomic and fasting blood subset, A. intestini was correlated with circulating plasminogen activator inhibitor-1, a pro-inflammatory marker (rho = 0·40), but no associations remained significant upon correction for multiple testing. An index reflecting overall inflammatory potential of the diet was associated with specific microbes, but not overall diversity of the gut microbiome in our study. Findings from this preliminary study warrant further research in larger samples and prospective cohorts.
The coronavirus disease 2019 (COVID-19) outbreak in Wuhan, China, spread rapidly throughout China and gradually to some countries abroad. How is the development of an epidemic controlled? Early diagnosis is one of the important contents in prevention and control. COVID-19 patients with early mild pneumonia often lack typical evidence to make a definitive diagnosis. Based on the analysis of the cases of 4 patients, this article finds that early diagnosis requires a combination of epidemiology, clinical manifestations, imaging, and etiology, with particular emphasis on epidemiology history and chest computed tomography (CT) manifestations.
Diet modifies the risk of colorectal cancer (CRC), and inconclusive evidence suggests that yogurt may protect against CRC. We analysed the data collected from two separate colonoscopy-based case–control studies. The Tennessee Colorectal Polyp Study (TCPS) and Johns Hopkins Biofilm Study included 5446 and 1061 participants, respectively, diagnosed with hyperplastic polyp (HP), sessile serrated polyp, adenomatous polyp (AP) or without any polyps. Multinomial logistic regression models were used to derive OR and 95 % CI to evaluate comparisons between cases and polyp-free controls and case–case comparisons between different polyp types. We evaluated the association between frequency of yogurt intake and probiotic use with the diagnosis of colorectal polyps. In the TCPS, daily yogurt intake v. no/rare intake was associated with decreased odds of HP (OR 0·54; 95 % CI 0·31, 0·95) and weekly yogurt intake was associated with decreased odds of AP among women (OR 0·73; 95 % CI 0·55, 0·98). In the Biofilm Study, both weekly yogurt intake and probiotic use were associated with a non-significant reduction in odds of overall AP (OR 0·75; 95 % CI 0·54, 1·04) and (OR 0·72; 95 % CI 0·49, 1·06) in comparison with no use, respectively. In summary, yogurt intake may be associated with decreased odds of HP and AP and probiotic use may be associated with decreased odds of AP. Further prospective studies are needed to verify these associations.
Innovation contributes to a firm's long-term competitive advantages but also involves significant risk and uncertainty. As agency theory predicts, CEOs are self-interested and risk-averse, and thus are reluctant to engage in innovation investments. However, the extent to which CEOs are self-interested and the mechanisms through which self-interested CEOs affect firm innovation have not been empirically tested. To fill this gap, we propose that CEOs possess a mix of both self-preserving and other-regarding motives, and build a mediation model in which CEO values affect firm innovation via firms’ long-term orientation. Based on a three-phase (from 2014 to 2016) survey of 436 Chinese manufacturing firms, we find that CEOs with high self-regarding values reduce innovation efforts and performance by damaging a firm's long-term orientation. Moreover, CEO tenure, CEO duality, and environmental uncertainty weaken the relationship between CEO values and firm innovation via long-term orientation. Our study enriches the innovation literature by extending the basic assumptions of agency theory and by providing empirical evidence to determine whether and how self-regarded CEOs affect firm innovation.
Only 30% or fewer of individuals at clinical high risk (CHR) convert to full psychosis within 2 years. Efforts are thus underway to refine risk identification strategies to increase their predictive power. Our objective was to develop and validate the predictive accuracy and individualized risk components of a mobile app-based psychosis risk calculator (RC) in a CHR sample from the SHARP (ShangHai At Risk for Psychosis) program.
In total, 400 CHR individuals were identified by the Chinese version of the Structured Interview for Prodromal Syndromes. In the first phase of 300 CHR individuals, 196 subjects (65.3%) who completed neurocognitive assessments and had at least a 2-year follow-up assessment were included in the construction of an RC for psychosis. In the second phase of the SHARP sample of 100 subjects, 93 with data integrity were included to validate the performance of the SHARP-RC.
The SHARP-RC showed good discrimination of subsequent transition to psychosis with an AUC of 0.78 (p < 0.001). The individualized risk generated by the SHARP-RC provided a solid estimation of conversion in the independent validation sample, with an AUC of 0.80 (p = 0.003). A risk estimate of 20% or higher had excellent sensitivity (84%) and moderate specificity (63%) for the prediction of psychosis. The relative contribution of individual risk components can be simultaneously generated. The mobile app-based SHARP-RC was developed as a convenient tool for individualized psychosis risk appraisal.
The SHARP-RC provides a practical tool not only for assessing the probability that an individual at CHR will develop full psychosis, but also personal risk components that might be targeted in early intervention.
The synergetic effects of surface smoothing exhibited during the inductively coupled plasma reactive ion etching (ICP-RIE) of free-standing polycrystalline diamonds (PCDs) were investigated. Changing the assistive gas types generated variable surface oxidation states and chemical environments that resulted in different etching rates and surface morphologies. The main reaction bond mechanism (C–O) during ICP-RIE and the ratio of C–O–C/O–C=O associated with the existence of a uniform smooth surface with root mean square (RMS) roughness of 2.36 nm were observed. An optimal process for PCD smoothing at high etching rate (4.6 μm/min) was achieved as follows: 10% gas additions of CHF3 in O2 plasma at radio frequency power of 400 W. The further etched ultra-smooth surface with RMS roughness <0.5 nm at etching rate of 0.23 μm/min that being produced by transferring this optimum recipe on single crystal diamonds with surface patterns confirmed the effectiveness of the fast smoothing approach and its feasibility for diamond surface patterning.
Resource allocation planning for emergency medical services (EMS) systems determines appropriate resources including what paramedic qualification and how rapidly to respond to patients for optimal outcomes. The British Columbia Emergency Health Services implemented a revised response plan in 2013.
A pre- and post-methodology was used to evaluate the effect of the resource allocation plan revision on 24-hour mortality. All adult cases with evaluable outcome data (obtained through linked provincial health administrative data) were analyzed. Multivariable logistic regression was used to adjust for variations in other significant associated factors. Interrupted time series analysis was used to estimate immediate changes in level or trend of outcome after the start of the revised resource allocation plan implementation, while simultaneously controlling for pre-existing trends.
The derived cohort comprised 562,546 cases (April 2012–March 2015). When adjusted for age, sex, urban/metro region, season, day, hour, and dispatch determinant, the probability of dying within 24 hours of an EMS call was 7% lower in the post-resource allocation plan-revision cohort (OR = 0.936; 95% CI: 0.886–0.989; p = 0.018). A subgroup analysis of immediately life-threatening cases demonstrated similar effect (OR = 0.890; 95% CI: 0.808–0.981; p = 0.019). Using time series analysis, the descending changes in overall 24-hour mortality trend and the 24-hour mortality trend in immediately life-threatening cases, were both statistically significant (p < 0.001).
Comprehensive, evidence-informed reconstruction of a provincial EMS resource allocation plan is feasible. Despite change in crew level response and resource allocation, there was significant decrease in 24-hour mortality in this pan-provincial population-based cohort.