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One of the leading challenges in chemical sciences is the separation of complex mixtures. This is of vital importance for areas such as commodity chemical generation, where there is a need for the generation of high-purity chemical streams. Due to this, there has been a strong push toward the investigation of new materials capable of achieving chemoselective separation, with self-assembled materials having shown a great deal of promise for such separations. Many self-assembled materials are desirable candidates due to their low-cost synthesis, structural self-regulation, tunable properties, and an overall ease of composite material preparation. In this article, we aim to introduce examples of novel self-assembled materials and their practical usage in chemical separations. The specific approaches to fabricate these materials, as well as the strengths and shortcomings associated with their structures, will also be described. The strategies presented here will emphasize the production and employment of nonconventional self-assembled materials that exhibit a high potential for the advancement of the science of chemical separations.
Not all plant-based and animal foods exert the same health effects due to their various nutrient compositions. We aimed to assess the quality of plant-based vs. animal foods in relation to mortality in a prospective cohort study. Using data collected from a nationally representative sample of 36,825 adults in the National Health and Nutrition Examination Survey 1999-2014, we developed a de novo Comprehensive Diet Quality Index (cDQI) that assesses the quality of 17 foods based on the healthfulness, and separately scored the quality of 11 plant-based foods in a plant-based Diet Quality Index (pDQI) and 6 animal foods in an animal-based Diet Quality index (aDQI). Mortality from all causes, heart disease, and cancer were obtained from linkage to the National Death Index through December 31, 2015. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) after multivariable adjustments. During a median follow-up of 8.3 years, 4,669 all-cause deaths occurred, including 798 deaths due to heart disease and 1,021 due to cancer. Compared to individuals in the lowest quartile, those in the highest quartile of cDQI had a lower risk of all-cause mortality (HR=0.75, 95% CI: 0.65, 0.86; P-trend<0.001), which largely reflected the inverse relationship between quality of plant-based foods (pDQI) and all-cause mortality (HR=0.66; 95% CI: 0.58, 0.74, P-trend<0.001). No independent association was found for the quality of animal-foods (aDQI) and mortality. Our results suggest that consuming healthy plant-based foods is associated with lower all-cause mortality among US adults.
We aimed to describe the clinical features in coronavirus disease 2019 (COVID-19) cases. We studied 134 critically ill COVID-19 cases from 30 December 2019 to 20 February 2020 in an intensive care unit (ICU) at Wuhan Jinyintan Hospital. Demographics, underlying diseases, therapy strategies and test results were collected and analysed from patients on admission, admission to the ICU and 48 h before death. The non-survivors were older (65.46 (s.d. 9.74) vs. 46.45 (s.d. 11.09)) and were more likely to have underlying diseases. The blood group distribution of the COVID-19 cases differed from that of the Han population in Wuhan, with type A being 43.85%; type B, 26.92%; type AB, 10% and type O, 19.23%. Non-survivors tend to develop more severe lymphopaenia, with higher C-reactive protein, interleukin-6, procalcitonin, D-dimer levels and gradually increased with time. The clinical manifestations were non-specific. Compared with survivors, non-survivors more likely to have organ function injury, and to receive mechanical ventilation, either invasively or noninvasively. Multiple organ failure and secondary bacterial infection in the later period is worthy of attention.
Universal masking for healthcare workers and patients in hospitals was adopted to combat coronavirus disease 2019 (COVID-19), with compliance rates of 100% and 75.9%, respectively. Zero rates of nosocomial influenza A, influenza B, and respiratory syncytial virus infection were achieved from February to April 2020, which was significantly lower than the corresponding months in 2017–2019.
A higher dietary intake or serum concentration of betaine has been associated with greater lean body mass in middle-aged and older adults. However, it remains unknown whether betaine intake is associated with age-related loss of skeletal muscle mass (SMM). We assessed the association between dietary betaine intake and relative changes in SMM after 3 years in middle-aged adults. A total of 1242 participants aged 41–60 years from the Guangzhou Nutrition and Health Study 2011–2013 and 2014–2017 with body composition measurements by dual-energy X-ray absorptiometry were included. A face-to-face questionnaire was used to collect general baseline information. After adjustment for potential confounders, multiple linear regression found that energy-adjusted dietary betaine intake was significantly and positively associated with relative changes (i.e. percentage loss or increase) in SMM of legs, limbs and appendicular skeletal mass index (ASMI) over 3 years of follow-up (β 0·322 (se 0·157), 0·309 (se 0·142) and 0·303 (se 0·145), respectively; P < 0·05). The ANCOVA models revealed that participants in the highest betaine tertile had significantly less loss in SMM of limbs and ASMI and more increase in SMM of legs over 3 years of follow-up, compared with those in the bottom betaine tertile (all Ptrend < 0·05). In conclusion, our findings suggest that elevated higher dietary betaine intake may be associated with less loss of SMM of legs, limbs and ASMI in middle-aged adults.
This research involves a compact wideband circularly-polarized antenna array, which consists of a sequential rotating phase feed network, 2 × 2 mushroom-type metamaterial (MTM) unit, and so on. Each antenna array unit contains a microstrip feedline, an L-shaped slot antenna, and so on. The MTM-based antennas were incorporated with a sequential-phase network of sequentially rotated series-parallel feed to achieve wideband operation. The operational bandwidth and the radiation model in the high-frequency area were improved through the adjustment of spacing between the L-shaped slots while maintaining the size and structure of the MTM. The proposed design had dimensions of 80 mm × 80 mm × 3.5 mm (~1.64 λ0 × 1.64 λ0 × 0.072 λ0 at 6.15 GHz), and it was simulated, fabricated, and tested.
Human fatigue is a major risk factor in transportation that contributes, directly or indirectly, to a large number of traffic accidents. Though many studies have investigated fatigue-inducing factors in transportation to manage human fatigue more efficiently, there are limited studies related to vessel traffic service (VTS). To fill this gap, this work aims to determine the key causal factors and symptoms of human fatigue with a focus on VTS operations. Achieving this aim is hindered by the problems of no standard definition of task-related fatigue and limited data sources. To solve these problems, this paper proposes a novel definition of task-related human fatigue, a task-driven approach for identifying causal factors and a causal network-based approach for selecting key causal factors. Twelve key causal factors of human fatigue in VTS were identified and analysed. In addition, it was found that VTS operators suffered from multidimensional fatigue, especially physical fatigue. The results provide a foundation and future directions for designing interventions to manage human fatigue.
A new, modified version of the cable-suspended Ice and Bedrock Electromechanical Drill (IBED) was designed for drilling in firn, ice, debris-rich ice and rock. The upper part of the drill is almost the same for all drill variants and comprises four sections: cable termination, a slip-ring section, an antitorque system and an electronic pressure chamber. The lower part of the IBED comprises an auger core barrel, reamers, a core barrel for ice/debris-ice drilling and a conventional geological single-tube core barrel or custom-made double-tube core barrel. First, the short and full-scale field versions of the IBED were tested at an outdoor testing stand and a testing facility with a 12.5 m-deep ice well. Then, in the 2018–2019 summer season, the IBED was tested in the field at a site ~12 km south of Zhongshan Station, East Antarctica, and a ~6 cm bedrock core was recovered from a 198 m-deep borehole. A total of 18 d was required to penetrate the ice sheet. The retrieved core samples of blue ice, basal ice and bedrock provided valuable information regarding the Earth's paleo-environment.
The role of severe respiratory coronavirus virus 2 (SARS-CoV-2)–laden aerosols in the transmission of coronavirus disease 2019 (COVID-19) remains uncertain. Discordant findings of SARS-CoV-2 RNA in air samples were noted in early reports.
Sampling of air close to 6 asymptomatic and symptomatic COVID-19 patients with and without surgical masks was performed with sampling devices using sterile gelatin filters. Frequently touched environmental surfaces near 21 patients were swabbed before daily environmental disinfection. The correlation between the viral loads of patients’ clinical samples and environmental samples was analyzed.
All air samples were negative for SARS-CoV-2 RNA in the 6 patients singly isolated inside airborne infection isolation rooms (AIIRs) with 12 air changes per hour. Of 377 environmental samples near 21 patients, 19 (5.0%) were positive by reverse-transcription polymerase chain reaction (RT-PCR) assay, with a median viral load of 9.2 × 102 copies/mL (range, 1.1 × 102 to 9.4 × 104 copies/mL). The contamination rate was highest on patients’ mobile phones (6 of 77, 7.8%), followed by bed rails (4 of 74, 5.4%) and toilet door handles (4 of 76, 5.3%). We detected a significant correlation between viral load ranges in clinical samples and positivity rate of environmental samples (P < .001).
SARS-CoV-2 RNA was not detectable by air samplers, which suggests that the airborne route is not the predominant mode of transmission of SARS-CoV-2. Wearing a surgical mask, appropriate hand hygiene, and thorough environmental disinfection are sufficient infection control measures for COVID-19 patients isolated singly in AIIRs. However, this conclusion may not apply during aerosol-generating procedures or in cohort wards with large numbers of COVID-19 patients.
In maritime search and rescue (SAR), commanders need to understand the task execution efficiency of each SAR unit in real time to improve the overall efficiency of SAR efforts. This study proposes a method to evaluate the progress of maritime SAR missions using automatic identification system (AIS) data. First, the positioning accuracy of the AIS data was improved according to the relationship between position, speed, and course. Second, the historical track of the SAR ship was used to generate the SAR completion area based on a line buffer algorithm. The SAR completion area and SAR mission area were then superimposed to determine the overall progress of the SAR mission. The proposed method has been deployed within the SAR software on-board Haixun01 (China's largest and most advanced large-scale cruise rescue ship) since 2017 and has played an important role in devising SAR strategies and tracking mission progress, during several SAR actions.
Disasters such as an earthquake, a flood, and an epidemic usually lead to large numbers of casualties accompanied by disruption of the functioning of local medical institutions. A rapid response of medical assistance and support is required. Mobile hospitals have been deployed by national and international organizations at disaster situations in the past decades, which play an important role in saving casualties and alleviating the shortage of medical resources. In this paper, we briefly introduce the types and characteristics of mobile hospitals used by medical teams in disaster rescue, including the aspects of structural form, organizational form, and mobile transportation. We also review the practices of mobile hospitals in disaster response and summarize the problems and needs of mobile hospitals in disaster rescue. Finally, we propose the development direction of mobile hospitals, especially on the development of intelligence, rapid deployment capabilities, and modularization, which provide suggestions for further research and development of mobile hospitals in the future.
CBS becomes more prevalent as the population ages. CBS is characterized by the triad of impairment of vision, complex visual hallucinations with insight, mentally normal people. Although visual hallucinations in the elderly are often associated with dementia with Lewy body, Alzheimer's disease and delirium, they are excluded from the diagnosis of typical CBS. Here, we describe three typical CBS patients whose visual hallucinations developed after bilateral severe visual impairment due to diabetic retinopathy. The effectiveness of agomelatine adds to evidence implicating serotonergic and melatoninergic pathways in the pathogenesis of visual hallucinations.
The average age of these three patients (2 males and 1 female) is 71. Except for the visual hallucinations, all patients showed no psychiatric symptoms or cognitive decline or neurological focal signs. They were frequently upset by the fact of hallucinating, fearing that they are losing their minds. They lived in fear of impending insanity, guilty feeling, unhappy mood, insomnia. The frequency of visual hallucinations stopped with agomelatine 25 mg/day for 3 weeks in these cases.
To our knowledge, this is the first report describing the effectiveness of agomelatine in treating typical CBS patients and indicates that agomelatine is an safer option for the treatment of CBS, especially in the elderly, diabetic population. Therapeutic options for CBS still remain poor and of uncertain benefit for the individual patient. CBS has a high prevalence rate (0.4%–30%) among the visually impaired. Clinicians must ask elderly people with visual impairment whether they have hallucinations. Firm reassurance that the syndrome is not related to mental illness is a major relief to an elderly person burdened already with failing vision.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
On a compact Lie group
, we study the Bochner–Riesz mean
of the Fourier series for a function
. At the critical index
, we obtain the convergence rate for
is a function in the block-Sobolev space. The main theorems extend some known results on the
Previous studies regarding associations between depressive symptoms and suicidality (suicidal ideation, plans and attempts) have usually employed a variable-centred approach, without considering the individual variance in time-varying changes of depressive symptoms. Through 10-year follow-up of a large cohort of Chinese adolescents exposed to the 2008 Wenchuan earthquake, this study examined whether individual variance in depressive symptoms during the early phases post-earthquake could generate different suicidality outcomes in young adulthood.
A total of 1357 Chinese adolescents exposed to the Wenchuan earthquake were surveyed on depressive symptoms and other variables at 6, 18 and 30 months post-earthquake. In total, 799 participants responded to the 10-year follow-up and completed an online survey covering suicidality and other variables. The analytic sample was 744 participants who had valid data on depressive symptoms and suicidality. Data were analysed using logistic regressions.
Prevalence estimates of past-year suicidal ideation, suicide plans and suicide attempts measured at 10 years post-earthquake were found to be 10.8%, 7.3% and 3.0%, respectively. Five trajectories of depressive symptoms were classified: resistance (54.4%), chronicity (13.3%), recovery (10.4%), delayed dysfunction (12.0%) and relapsing/remitting (10.0%). After controlling for covariates, whole-sample regressions revealed only the relapsing/remitting depressive trajectory remained significantly predictive of suicidality. Moreover, males not females in the chronic group were more likely to have suicide plans.
The findings highlight the importance of detecting disaster survivors with different trajectories of mental status and providing with them individualised and effective mental health services, to decrease their risk of suicidality in the future.
To improve the corrosion resistance and to increase the hardness of copper substrate in marine environment, the Cu-Ni/Ni-P composite coatings were prepared on the copper substrate using the galvanostatic electrolytic deposition method. The deposition current densities were explored to find the optimized deposition conditions for forming the composite coatings. Corrosion resistance properties were analyzed using the polarization curves and electrochemical impedance spectroscopy (EIS). Considering the corrosion resistance and hardness, the −20 mA/cm2 was selected to deposit Cu-Ni coatings on copper substrate and the −30 mA/cm2 was selected to deposit Ni-P coating on the Cu-Ni layer. The Cu-Ni/Ni-P composite coatings not only exhibited superior corrosion resistance compared to single Cu-Ni coating in 3.5 wt.% NaCl solution, but also showed much better mechanical properties than single Cu-Ni coating.
Many previous studies argue that harsher forestry legislation should be enforced to handle the problem of tree poaching. However, empirical studies on the behavioural analysis of poachers’ decision making is largely lacking. Drawing from conversations with 65 inmates imprisoned for Forestry Act offences in Taiwan, we discuss the reasons behind the intention whether or not to stop tree poaching. The majority (81.5%) of the sample expressed their intention to stop tree poaching. Among the 16 demographic, offence and punishment characteristics, we identified only four variables to be included in the final logistic regression model to predict the decision to stop. We found that (1) having no previous experience of stout camphor tree (Cinnamomum kanehirae) theft, taking a log from a stout camphor tree and selling it to buyers; or (2) higher level of education could predict a greater likelihood of intending to quit. Given the limitation of the existing control approach, we propose a restorative justice approach to the poaching problem. A restorative justice approach, instead of focusing solely on the violation of law, recognizes the harm done and forms collaborative work to repair the harm and prevent future wrongdoings. It also helps break the vicious cycle of a poaching subculture.