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Origami, the ancient paper folding art has inspired the engineering equipment and design for decades. The basic concept of origami is very general, which leads to applications ranging from small scale to large scale. Recently, researchers are interested in being able to create self-folding structures. Such a structure enables kinematic manipulation by external forces or moments without folding and/or unfolding operations. This is a beneficial application for many fields including aerospace systems, robots, small devices and self-assembly systems. In this paper, the investigation and analyses of the previous literatures on the key driving force of the actuation structure, including the heat, light, electricity, gas and other actuation methods. The aims are to provide researchers and practitioners with the support to systematically understand the latest technologies in this important and evolving field, with inspiration and direction for follow-up.
Primary care physicians can play a key role in supporting patients after behavioural weight loss, though little is known about communication between patients and physicians during this time. Adults (n=139) in a behavioural weight loss trial (delivered outside of primary care) who attended a primary care appointment after an initial weight loss period were surveyed to assess weight-related communication at their most recent appointment. Most participants (78%) reported discussing weight with their physician. Participants who discussed weight, compared to those who did not, lost more weight, had higher blood pressure, and were more likely to be male. Most (89%) reported that their physician was supportive of their weight loss, but only a few participants (6.9%) reported that their physician gave feedback on medical parameters. Areas for improvement identified include physicians providing universal support for modest weight changes and providing interpretation of medical measurements that changed due to weight loss.
To assess the association between food insecurity and depression symptom severity stratified by sex, and test for evidence of effect modification by social network characteristics.
A population-based cross-sectional study. The nine-item Household Food Insecurity Access Scale captured food insecurity. Five name generator questions elicited network ties. A sixteen-item version of the Hopkins Symptom Checklist for Depression captured depression symptom severity. Linear regression was used to estimate the association between food insecurity and depression symptom severity while adjusting for potential confounders and to test for potential network moderators.
In-home survey interviews in south-western Uganda.
All adult residents across eight rural villages; 96 % response rate (n 1669).
Severe food insecurity was associated with greater depression symptom severity (b=0·4, 95 % CI 0·3, 0·5, P<0·001 for women; b=0·3, 95 % CI 0·2, 0·4, P<0·001 for men). There was no evidence of effect modification by social network factors for women. However, for men who are highly embedded within in their village social network, and (separately) for men who have few poor contacts in their personal network, the relationship between severe food insecurity and depression symptoms was stronger than for men on the periphery of their village social network, and for men with many poor personal network contacts, respectively.
In this population-based study from rural Uganda, food insecurity was associated with mental health for both men and women. Future research is needed on networks and food insecurity-related shame in relation to depression symptoms among food-insecure men.
Snowmelt regions on Greenland ice are mapped daily with the SeaWinds wideswath Ku-band (13.4 GHz) scatterometer on the QuikSCAT satellite. The approach exploits the high temporal resolution of SeaWinds/QuikSCAT data for the melt mapping using diurnal backscatter change independent of the absolute calibration. The results reveal several pronounced melting and refreezing events, and effects of topography are evident in the melt patterns. The spatial resolution is sufficient to identify melt features on the Sukker-toppen Iskappe west of the main ice sheet. An anomalous warming event, caused by down-ward mixing of warm air, is detected in late September 1999 over the west flank of the southern Greenland ice sheet. Time-series images of melt regions are presented over the period from summer to the fall freeze-up. The satellite observations are verified with in situ measurements from the Greenland Climate Network stations.
Maruca vitrata (Fabricius, 1787) is a cryptic pantropical species of Lepidoptera that are comprised of two unique strains that inhabit the American continents (New World strain) and regions spanning from Africa through to Southeast Asia and Northern Australia (Old World strain). In this study, we de novo assembled the complete mitochondrial genome sequence of the New World legume pod borer, M. vitrata, from shotgun sequence data generated on an Illumina HiSeq 2000. Phylogenomic comparisons were made with other previously published mitochondrial genome sequences from crambid moths, including the Old World strain of M. vitrata. The 15,385 bp M. vitrata (New World) sequence has an 80.7% A+T content and encodes the 13 protein-coding, 2 ribosomal RNA and 22 transfer RNA genes in the typical orientation and arrangement of lepidopteran mitochondrial DNAs. Mitochondrial genome-wide comparison between the New and Old World strains of M. vitrata detected 476 polymorphic sites (4.23% nucleotide divergence) with an excess of synonymous substitution as a result of purifying selection. Furthermore, this level of sequence variation suggests that these strains diverged from ~1.83 to 2.12 million years ago, assuming a linear rate of short-term substitution. The de novo assemblies of mitochondrial genomes from next-generation sequencing (NGS) reads provide readily available data for similar comparative studies.
School attendance rates in sub-Saharan Africa are among the lowest worldwide, placing children at heightened risk for poor educational and economic outcomes. One understudied risk factor for missed schooling is household water insecurity, which is linked to depression among women and may increase children's water-fetching burden at the expense of educational activities, particularly among children of depressed caregivers. In this study conducted in rural Uganda, we assessed the association between household water insecurity and child school participation and the mediating pathways behind these associations.
We conducted a population-based, cross-sectional study of female household heads (N = 257) and their children ages 5–17 (N = 551) in the rural regions surrounding the town of Mbarara, in southwestern Uganda. We used multivariable linear regressions to estimate the association between water insecurity and missed schooling. We then assessed the extent to which the association was mediated by caregiver depression.
Among children, water insecurity had a statistically significant association with the number of missed school days (a standard deviation increase in water insecurity resulted in 0.30 more missed school days in the last week). The estimated association was partially mediated by caregiver depression. When stratified by sex, this mediating pathway remained significant for boys, but not among girls.
Water insecurity is a risk factor for missed schooling among children in rural Uganda. Caregiver depression partially mediated this relationship. Also addressing caregiver mental health in water insecure families may more fully address the needs of sub-Saharan African families and promote educational participation among youth.
Worldwide, tobacco smoke is still the leading cause of preventable morbidity and mortality. Many smokers develop chronic smoking-related conditions that require emergency department (ED) visits. However, best practices for ED smoking cessation counselling are still unclear.
A randomized controlled trial was conducted to determine whether an “ask, advise, and refer” approach increases 12-month, 30-day quit rates in the stable adult ED smoking population compared to usual care. Patients in the intervention group were referred to a community counselling service that offers a quitline, a text-based program, and a Web-based program. Longitudinal intention-to-treat analyses were performed.
From November 2011 to March 2013, 1,295 patients were enrolled from one academic tertiary care ED. Six hundred thirty-five were allocated to usual care, and 660 were allocated to intervention. Follow-up data were available for 70% of all patients at 12 months. There was no statistically significant difference in 12-month, 30-day quit rates between the two groups. However, there was a trend towards higher 7-day quit attempts, 7-day quit rates, and 30-day quit rates at 3, 6, and 12 months in the intervention group.
In this study, there was a trend towards increased smoking cessation following referral to a community counselling service. There was no statistically significant difference. However, if ED smoking cessation efforts were to provide even a small positive effect, such an intervention may have a significant public health impact given the extensive reach of emergency physicians.
To determine the source of a healthcare-associated outbreak of Pantoea agglomerans bloodstream infections.
Epidemiologic investigation of the outbreak.
Oncology clinic (clinic A).
Cases were defined as Pantoea isolation from blood or catheter tip cultures of clinic A patients during July 2012–May 2013. Clinic A medical charts and laboratory records were reviewed; infection prevention practices and the facility’s water system were evaluated. Environmental samples were collected for culture. Clinical and environmental P. agglomerans isolates were compared using pulsed-field gel electrophoresis.
Twelve cases were identified; median (range) age was 65 (41–78) years. All patients had malignant tumors and had received infusions at clinic A. Deficiencies in parenteral medication preparation and handling were identified (eg, placing infusates near sinks with potential for splash-back contamination). Facility inspection revealed substantial dead-end water piping and inadequate chlorine residual in tap water from multiple sinks, including the pharmacy clean room sink. P. agglomerans was isolated from composite surface swabs of 7 sinks and an ice machine; the pharmacy clean room sink isolate was indistinguishable by pulsed-field gel electrophoresis from 7 of 9 available patient isolates.
Exposure of locally prepared infusates to a contaminated pharmacy sink caused the outbreak. Improvements in parenteral medication preparation, including moving chemotherapy preparation offsite, along with terminal sink cleaning and water system remediation ended the outbreak. Greater awareness of recommended medication preparation and handling practices as well as further efforts to better define the contribution of contaminated sinks and plumbing deficiencies to healthcare-associated infections are needed.
EVA foams, like all other polymers, also exhibit strain-rate effects and hysteresis. However, currently available approaches for predicting the mechanical response of polymeric foam subjected to an arbitrarily imposed loading history and strain-rate effect are highly limited. Especially, the strain rates in the intermediate rate domain (between 100 and 102 s–1) are extremely difficult to study. The use of data generated through the drop tower technique for implementation in constitutive equations or numerical models has not been considered in past studies. In this study, an experiment including a quasi-static compression test and drop impact tests with a high speed camera was conducted. An inverse analysis technique combined with a finite element model for material parameter identification was developed to determine the stress–strain behavior of foam at different specific strain rates. It was used in this study to simulate multiple loading and unloading cycles on foam specimens, and the results were compared with experimental measurements.
We investigate the formation of young massive clusters near the nuclei in NGC 6946, IC 342, Maffei II, and NGC 7714, using ground-based mid-infrared [NeII] imaging. We derive the cluster formation efficiency and cluster mass function, and the results suggest that environmental effects on YMC formation may not be significant.
In this study, the properties of surface acoustic wave (SAW) filters, including phase velocity and electromechanical coupling coefficient (K2) are investigated. The effective surface permittivity (ESP) method was employed to estimate the K2 of bulk materials (single layer) and multi-layer (double-layer and trilayer) structures. In the cases of bulk materials, the calculation results agree with the experimental data, and the errors are less than 7% for quartz. In the cases of double-layer materials, the phase velocity and K2 of various materials, such as ZnO/Diamond and LiNbO3/Diamond, were acquired, and the results demonstrate that LiNbO3/diamond is the optimal choice for high-frequency SAW devices. For the cases of trilayer, the structure of ZnO/PZT/diamond has relatively high K2 and phase velocity. Therefore, this structure is the optimal trilayer structure for high-frequency SAW devices. The study demonstrates that ESP method can be successfully used for estimating SAW properties in piezoelectric multi-layer structures even though the structures contain nonpiezoelectric film (diamond). The proposed numerical computation has the potential to shorten the developing time of SAW device.
We have developed a low cost and convenient approach to fabricate ITO-comparable transparent electrodes by using solution process of silver nanowires mixed with poly peroxotitanic acid (PPT) gel. The PPT gel is applied to connect the dispersed silver nanowires to preserve its high conductivity while remaining transparency and reducing surface roughness of the transparent electrode. The silver nanowires were synthesized via a modified polyol method, and the PPT gels were prepared by sol-gel method in appropriate concentrations. After applying the PPT gels, the sheet resistance of the transparent electrodes was improved from 192 Ω/□ to 44.7 Ω/□ with a transmittance of 81 %. And the roughness (RMS) was decreased from 106.3 nm to 48.1 nm. The PPT gel also improved the reliability of the proposed electrodes, which the conductivity was remained after general atmospheric storage of 6 months. We also demonstrate an Alq3 based OLED with the proposed transparent electrodes.
There is increasing recognition that, in addition to negative psychological consequences of trauma such as post-traumatic stress disorder (PTSD), some individuals may develop post-traumatic growth (PTG) following such experiences. To date, however, data regarding the prevalence, correlates and functional significance of PTG in population-based samples are lacking.
Data were analysed from the National Health and Resilience in Veterans Study, a contemporary, nationally representative survey of 3157 US veterans. Veterans completed a survey containing measures of sociodemographic, military, health and psychosocial characteristics, and the Posttraumatic Growth Inventory-Short Form.
We found that 50.1% of all veterans and 72.0% of veterans who screened positive for PTSD reported at least ‘moderate’ PTG in relation to their worst traumatic event. An inverted U-shaped relationship was found to best explain the relationship between PTSD symptoms and PTG. Among veterans with PTSD, those with PTSD reported better mental functioning and general health than those without PTG. Experiencing a life-threatening illness or injury and re-experiencing symptoms were most strongly associated with PTG. In multivariable analysis, greater social connectedness, intrinsic religiosity and purpose in life were independently associated with greater PTG.
PTG is prevalent among US veterans, particularly among those who screen positive for PTSD. These results suggest that there may be a ‘positive legacy’ of trauma that has functional significance for veterans. They further suggest that interventions geared toward helping trauma-exposed US veterans process their re-experiencing symptoms, and to develop greater social connections, sense of purpose and intrinsic religiosity may help promote PTG in this population.
We describe trends in incidence rates of methicillin-resistant Staphylococcus aureus (MRSA) in HIV-infected and HIV-uninfected patients enrolled in a large northern California Health Plan, and the ratio of MRSA to methicillin-susceptible S. aureus (MSSA) case counts. Between 1995 and 2010, 1549 MRSA infections were diagnosed in 14060 HIV-infected patients (11·0%) compared to 89546 MRSA infections in 6597396 HIV-uninfected patients (1·4%) (P = 0·00). A steady rise in MRSA infection rates began in 1995 in HIV-uninfected patients, peaking at 396·5 infections/100000 person-years in 2007. A more rapid rise in MRSA infection rates occurred in the HIV-infected group after 2000, peaking at 3592·8 infections/100000 in 2005. A declining trend in MRSA rates may have begun in 2008–2009. Comparing the ratio of MRSA to MSSA case counts, we observed that HIV-infected patients shouldered a greater burden of MRSA infection during most years of study follow-up compared to HIV-uninfected patients.
Hydrogen is commonly used in crystalline Si for passivation of defects and impurities. When single crystal Si undergoes a post-hydrogenation step, hydrogen-induced platelets have been shown to form in the first 100 nm of the Si. The same hydrogen platelets occur in homoepitaxial Si grown by low temperature (350°C or below) plasma-enhanced chemical vapor deposition with hydrogen dilution. This study has used transmission electron microscopy (TEM) to examine the structure of these hydrogen-induced platelets. TEM has shown that the platelets generally grow in tne (111) crystal planes of the Si. The size of the platelets, which ranges from 5 to 100 nm, increases with growth temperature but the density of platelets decrease at higher growth temperatures. The hydrogen platelets are not confined to the epitaxial Si layer only but also grow into the substrate. High resolution TEM shows the platelets dilate the silicon lattice by approximately 60% of a Si <111> plane. TEM has also shown that platelets cause no net displacement of the local Si lattice. Tilting experiments performed in the TEM show that the platelets are composed of a circular two-dimensional structure. Our results indicate that the hydrogen-induced platelets found in low temperature epitaxial Si are structurally the same as those seen in crystalline Si that has undergone post-hydrogenation processes.
We have compared the rates of CO formation on Cu and Cu oxide surfaces during the electrochemical reduction of CO2 in aqueous media. On metallic Cu surfaces, H2 formation is the main reaction at potentials less cathodic than –1.16 V(NHE). At this potential the formation of CO becomes significant, while CH4 appears at potentials more cathodic than –1.36 V(NHE). On electrodeposited Cu oxide surfaces there is a complex transient response. During reduction at constant potential (–1.1 V(NHE)), there is a large, transient cathodic current that corresponds to reduction of the oxide layer. After this initial oxide reduction, the current density stabilizes and the formation rates of H2 and CO show a more slowly varying transient behavior. The H2 formation rate is roughly 3x higher than on freshly cleaned Cu foil, but is largely independent of the thickness of the initial oxide layer. In contrast, the CO formation rate is at least one order of magnitude higher on the (reduced) Cu oxide samples than on Cu foil at the same potential. These results are interpreted as evidence that CO formation is enhanced at low-coordination number Cu sites present on freshly nucleated Cu clusters following oxide reduction.