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Drillholes on shells provide a useful way to investigate prey and predator relationships. The current study documents predator–prey interactions exemplified by a faunal assemblage of the fossil gastropod Turritella cingulifera from the Pleistocene Szekou Formation in Hengchun Peninsula, Taiwan. All recognisable skeletal and shell fragments that are larger than 3 mm in size were collected and recorded. Processed bulk sediments (5.24 kg) contained 1462 molluscan shells, including 824 specimens of T. cingulifera, and 27 non-molluscan invertebrates. In the current study, approximately 41.6% (609/1462) of molluscs are drilled with at least one hole. Drilling intensities (DIs) regardless of shell completeness in all gastropods, bivalves and the turritelline gastropod T. cingulifera are 0.546, 0.060 and 0.413, respectively. DI on turritellids is significantly lower than that on other gastropods (χ2= 21.039, P < 0.001). Furthermore, the percentage of drillholes that occur in multiply drilled specimens is 34.7% (95/275) for turritelline gastropods based on complete to nearly complete specimens (n = 588). Our study shows no significant preference of drillhole position either on the suture or on the whorl (χ2= 0.055, P = 0.814). Most drillholes are located in whorls two to four proximal to the aperture. Drillhole diameters of the shells with one drillhole and ones with multiple drillholes are 1.0 and 0.5 mm on average, and the results of Mann–Whitney tests indicate that they are significantly different (P < 0.001). The first turritelline gastropod shell with an incomplete drillhole from Taiwan is documented here. The dominant drilling predators were naticids based on the drillhole morphology and the presence of naticids in the same assemblage. No apparent prey size selectivity is observed, so a ‘size refugium’ does not exist for the turritellids in the current study.
Epilobium belongs to the family Onagraceae, which consists of approximately 200 species distributed worldwide, and some species have been used as medicinal plants. Epilobium nankotaizanense is an endemic and endangered herb that grows in the high mountains in Taiwan at an elevation of more than 3300 m. Alpine herbs are severely threatened by climate change, which leads to a reduction in their habitats and population sizes. However, only a few studies have addressed genetic diversity and population genetics. In the present study, we developed a new set of microsatellite markers for E. nankotaizanense using high-throughput genome sequencing data. Twenty polymorphic microsatellite markers were developed and tested on 30 individuals collected from three natural populations. These loci were successfully amplified, and polymorphisms were observed in E. nankotaizanense. The number of alleles per locus (A) ranged from 2.000 to 3.000, and the observed (Ho) and expected (He) heterozygosities ranged from 0.000 to 0.929 and from 0.034 to 0.631, respectively. The developed polymorphic microsatellite markers will be useful in future conservation genetic studies of E. nankotaizanense as well as for developing an effective conservation strategy for this species and facilitating germplasm collections and sustainable utilization of other Epilobium species.
Individuals with HIV are at increased risk for osteoporosis. A healthy diet with adequate Ca is recommended to promote bone health. However, lengthy nutritional assessments pose barriers to routine screenings in clinical practice. This study aimed to examine the validity and reproducibility of a six-item dietary Ca screening tool among Chinese individuals with HIV.
We conducted a two time-point study in an outpatient setting. Volunteers self-administered the six-item tool upon enrolment and again at 1-month follow-up. At baseline, participants also completed a validated FFQ and surveys regarding demographic and clinical risk factors.
Beijing, China; Shenzhen, Guangdong, China.
Upon enrolment, 127 individuals with HIV participated in the study, of whom 83 completed the follow-up screening.
Mean age of participants was 35·2 (sd 9·3) years, average BMI was 22·8 (sd 3·8) kg/m2 and 89 % were men. Among the participants, 54·7 % reported Ca intake less than 800 mg/d. The six-item tool demonstrated fair-to-moderate relative validity with a correlation of 0·39 and 75·7 % of subjects classified in same/adjacent quartiles as the reference, and moderate-to-good reproducibility with a correlation of 0·60 and 83·1 % of subjects classified in same/adjacent quartiles. Finally, receiver operating characteristic analyses yielded a sensitivity of 87·0 % and a specificity of 39·4 % with optimised cut-off level.
The six-item tool presented adequate validity and reproducibility to identify individuals with low Ca intake among the target population, providing a convenient instrument for categorising Ca intake in clinical practice, prompting referrals for further assessment, and raising awareness of dietary Ca in bone disease prevention.
To evaluate age-related differences in the independent/combined association of added sugar intake from soda and body adiposity with hyperuricaemia in gender-stratified US adults.
Consumption of added sugar from soda was calculated from 24-h dietary interviews and categorised into none, regular and excessive consumption. Hyperuricaemia was defined as serum uric acid levels >417 mmol/l in men and >357 mmol/l in women. Multiple regression models with interaction terms and logistic models adjusted for covariates were conducted under survey-data modules.
National Health and Nutrition Examination Survey during 2007–2016.
15 338 adults without gout, failing kidneys, an estimated glomerular filtration rate < 30 or diabetes were selected.
The age-stratified prevalence rate of hyperuricaemia was 18·8–20·4 % in males and 6·8–17·3 % in females. Hyperuricaemia prevalence of approximately 50 % was observed in young and middle age males who consumed excessive added sugar from soda. Excessive added sugar intake was observed to be associated with 1·5- to 2·0-fold and 2·0- to 2·3-fold increased risk of the probability of hyperuricaemia in young and middle age males and middle age females, respectively. Study participants, regardless of age or gender, who were obese and consumed excessive added sugar from soda had the highest risk of having hyperuricaemia.
Our study revealed that the association between hyperuricaemia and consumption of excessive added sugar from soda may vary by age and gender. Obese adults who consumed excessive added sugar from soda had the highest risk of hyperuricaemia, a finding that was found across all age-specific groups for both genders.
Attention-deficit/hyperactivity disorder (ADHD) is associated with a higher risk of burn injury than in the normal population. Nevertheless, the influence of methylphenidate (MPH) on the risk of burn injury remains unclear. This retrospective cohort study analysed the effect of MPH on the risk of burn injury in children with ADHD.
Data were from Taiwan's National Health Insurance Research Database (NHIRD). The sample comprised individuals younger than 18 years with a diagnosis of ADHD (n = 90 634) in Taiwan's NHIRD between January 1996 and December 2013. We examined the cumulative effect of MPH on burn injury risk using Cox proportional hazards models. We conducted a sensitivity analysis for immortal time bias using a time-dependent Cox model and within-patient comparisons using the self-controlled case series model.
Children with ADHD taking MPH had a reduced risk of burn injury, with a cumulative duration of treatment dose-related effect, compared with those not taking MPH. Compared with children with ADHD not taking MPH, the adjusted hazard ratio for burn injury was 0.70 in children taking MPH for <90 days (95% confidence interval (CI) 0.64–0.77) and 0.43 in children taking MPH for ≥90 days (95% CI 0.40–0.47), with a 50.8% preventable fraction. The negative association of MPH was replicated in age-stratified analysis using time-dependent Cox regression and self-controlled case series models.
This study showed that MPH treatment was associated with a lower risk of burn injury in a cumulative duration of treatment dose-related effect manner.
Limitations in sample size, overly inclusive antibiotic classes, lack of adjustment of key risk variables, and inadequate assessment of cases contribute to widely ranging estimates of risk factors for Clostridium difficile infection (CDI).
To incorporate all key CDI risk factors in addition to 27 antibiotic classes into a single comprehensive model.
Retrospective cohort study.
Kaiser Permanente Southern California.
Members of Kaiser Permanente Southern California at least 18 years old admitted to any of its 14 hospitals from January 1, 2011, through December 31, 2012.
Hospital-acquired CDI cases were identified by polymerase chain reaction assay. Exposure to major outpatient antibiotics (10 classes) and those administered during inpatient stays (27 classes) was assessed. Age, sex, self-identified race/ethnicity, Charlson Comorbidity Score, previous hospitalization, transfer from a skilled nursing facility, number of different antibiotic classes, statin use, and proton pump inhibitor use were also assessed. Poisson regression estimated adjusted risk of CDI.
A total of 401,234 patients with 2,638 cases of incident CDI (0.7%) were detected. The final model demonstrated highest CDI risk associated with increasing age, exposure to multiple antibiotic classes, and skilled nursing facility transfer. Factors conferring the most reduced CDI risk were inpatient exposure to tetracyclines and first-generation cephalosporins, and outpatient macrolides.
Although type and aggregate antibiotic exposure are important, the factors that increase the likelihood of environmental spore acquisition should not be underestimated. Operationally, our findings have implications for antibiotic stewardship efforts and can inform empirical and culture-driven treatment approaches.
Infect. Control Hosp. Epidemiol. 2015;36(12):1409–1416
Semiconductor quantum dots (QDs)-doped polystyrene (PS) microspheres with high luminescence were prepared using a self-assembly approach. Hydrophobic CdSe/ZnS QDs were first carboxylized by ligand exchange using mercaptocarboxylic acid. PS microspheres were separately encapsulated with polyethyleneimine via electrostatic interactions and then adsorbed with the carboxyl QDs to form QDs-doped microspheres. We then characterized the combinations using optical, electrical, and mechanical approaches and obtained the following findings: (i) microspheres can be fully coated by QD nanoparticles with a coverage rate of 1.0 pmole/cm2, in which QDs were evenly distributed on the surfaces; (ii) the anchored QDs exhibited similar optical property as they performed in isolated suspension; and (iii) the fluorescence of QDs-doped microspheres remained intact after stressed by ultrasound-induced cavitation, demonstrating the robustness of interactions between QDs and microspheres. The self-assembly approach developed in this study offered a facile and controllable strategy for preparation of QDs-encoded microparticles with high luminescence and stability.
Boron-doped, single (∼54 nm) or double (∼21 + 54 nm) Si1−xGex layers were epitaxially grown on 300-mm-diameter p−-Si(100) device wafers with 20 nm technology node design features, by ultrahigh vacuum chemical vapor deposition. The Si1−xGex/Si wafers were annealed in the temperature range of 950–1050 °C for 60 s to investigate the effect of annealing on possible changes of Ge content and Si stress near the Si1−xGex/Si interface. High spectral resolution, micro-Raman spectroscopy was used as a nondestructive characterization technique with five excitation wavelengths of 363.8, 441.6, 457.9, 488.0, and 514.5 nm. Ge diffusion and generation of compressive stress at the Si1−xGex/Si interface were measured on all annealed wafers. Ge diffusion and the accumulation of compressive Si stress after annealing showed significantly different behaviors between single- and double-layer Si1−xGex/Si wafers. Raman characterization results were compared with secondary ion mass spectroscopy and high-resolution x-ray diffraction results.
In this work, an accurate capacitance-voltage (C-V) model of organic Schottky diode is proposed. By taking the interface trap of the Schottky barrier into account, the capacitance model was derived from the junction and interface capacitance as a function of operation voltage. The model successfully describes the turn-around capacitance characteristic of Al/poly(3-hexylphiophene)(P3HT)/poly(3,4-ethylenedioxythiophene)poly(styrene sulfonate)(PEDOT:PSS)/IZO Schottky diode in the forward bias region. The simulated capacitances are in good agreement with our experimental data.