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In this cross-sectional population-based study, women had significantly higher crude incidence rates of both community-associated Clostridioides difficile infection (CA-CDI) and ambulatory antibiotic prescriptions compared to men in South Carolina in 2015. After adjustments for antibiotic prescription rates, there was no difference in the incidence rates of CA-CDI between the genders.
To examine the temporal trends in ambulatory antibiotic prescription fill rates and to determine the influences of age, gender, and location.
Population-based cohort study.
Ambulatory setting in South Carolina.
Patients ≤64 years of age from January 2012 to December 2017.
Aggregated pharmacy claims data for oral antibiotic prescriptions were utilized to estimate community antibiotic prescription rates. Poisson regression or Student t tests were used to examine overall temporal trend in antibiotic prescription rates, seasonal variation, and the trends across age group, gender, and rural versus urban location.
Overall antibiotic prescription rates decrease from 1,127 to 897 per 1,000 person years (P < .001). The decrease was more noticeable in persons aged <18 years (26%) and 18–39 years (20%) than in those aged 40–64 years (5%; P < .001 for all). Prescription rates were higher among females than males in all age groups, although this finding was the most pronounced in group aged 18–39 years (1,232 vs 585 per 1,000 person years; P < .0001). Annualized antibiotic prescription rates were higher during the winter months (December–March) than the rest of the year (1,145 vs 885 per 1,000 person years; P < .0001), and rates were higher in rural areas than in urban areas (1,032 vs 941 per 1,000 person years; P < .0001).
The decline in ambulatory antibiotic prescription rates is encouraging. Ongoing ambulatory antibiotic stewardship efforts across South Carolina should focus on older adults, rural areas, and during the winter season when antibiotic prescriptions peak.
Introduction: Hereditary angioedema (HAE) patients (both diagnosed and undiagnosed) commonly present to the emergency department (ED). Presenting symptoms (swelling and pain) may be erroneously attributed to common allergic and gastrointestinal conditions resulting in major delays in diagnosis and appropriate treatment. No published tools currently exist for HAE screening and management in undiagnosed disease. The overall goal of the study was to develop a HAE-RT tool for ED settings. Methods: A two-phase mixed methods approach was used to develop the HAE-RT Tool including: Phase 1: A Delphi Study [HAE specialists (N=9) and National Patient Advocacy Group Members (N=3)] was conducted to reach consensus (80% agreement) on predictor variables to include. Phase 2: A retrospective chart review was conducted to assess the predictive findings of the predictor variables. A convenient sample of patients presenting with angioedema (with and without HAE) between January 2012 January 2017 were included in the study. Results: Of the 12 experts invited, 9 (75%) participated in the Delphi study. Of 8 HAE-specific predictive variables, 4 reached consensuses including: (1) recurrent angioedema; (2) absence of urticaria; (3) past recurrent abdominal pain/swelling; (4) response to allergic therapy. The retrospective study included 85 patients (N=46 with HAE; N=39 non-HAE; overall 72% female). HAE patients were significantly more likely to have a family history of HAE (72% vs 0%; P<0.0001); previous recurrent angioedema (96%; P<0.009); present with no hives (91%; P<0.036); previous recurrent abdominal pain (80%; P<0.0001); and only 2% responded positively to allergy treatments (P<0.0001). Conclusion: Our study emphasizes the importance of key stakeholder involvement and feedback to facilitate the prioritization of important information that must be included in the design of an HAE-RT tool. The next step is to observe the effect of the HAE-RT tool on patient triage in the ED.
Anxiety disorders are common, and cognitive–behavioural therapy (CBT) is a first-line treatment. Candidate gene studies have suggested a genetic basis to treatment response, but findings have been inconsistent.
To perform the first genome-wide association study (GWAS) of psychological treatment response in children with anxiety disorders (n = 980).
Presence and severity of anxiety was assessed using semi-structured interview at baseline, on completion of treatment (post-treatment), and 3 to 12 months after treatment completion (follow-up). DNA was genotyped using the Illumina Human Core Exome-12v1.0 array. Linear mixed models were used to test associations between genetic variants and response (change in symptom severity) immediately post-treatment and at 6-month follow-up.
No variants passed a genome-wide significance threshold (P=5×10–8) in either analysis. Four variants met criteria for suggestive significance (P<5×10–6) in association with response post-treatment, and three variants in the 6-month follow-up analysis.
This is the first genome-wide therapygenetic study. It suggests no common variants of very high effect underlie response to CBT. Future investigations should maximise power to detect single-variant and polygenic effects by using larger, more homogeneous cohorts.
We previously reported an association between 5HTTLPR genotype and
outcome following cognitive–behavioural therapy (CBT) in child anxiety
(Cohort 1). Children homozygous for the low-expression short-allele
showed more positive outcomes. Other similar studies have produced mixed
results, with most reporting no association between genotype and CBT
To replicate the association between 5HTTLPR and CBT outcome in child
anxiety from the Genes for Treatment study (GxT Cohort 2,
n = 829).
Logistic and linear mixed effects models were used to examine the
relationship between 5HTTLPR and CBT outcomes. Mega-analyses using both
cohorts were performed.
There was no significant effect of 5HTTLPR on CBT outcomes in Cohort 2.
Mega-analyses identified a significant association between 5HTTLPR and
remission from all anxiety disorders at follow-up (odds ratio 0.45,
P = 0.014), but not primary anxiety disorder
The association between 5HTTLPR genotype and CBT outcome did not
replicate. Short-allele homozygotes showed more positive treatment
outcomes, but with small, non-significant effects. Future studies would
benefit from utilising whole genome approaches and large, homogenous
Household contacts of an index case of invasive meningococcal disease (IMD) are at increased risk of acquiring disease. In revising WHO guidance on IMD in sub-Saharan Africa, a systematic review was undertaken to assess the effect of chemoprophylaxis and of vaccination in preventing subsequent cases of IMD in household contacts following an index case. A literature search for systematic reviews identified a single suitable review on chemoprophylaxis in 2004 (three studies meta-analysed). A search for primary research papers published since 2004 on chemoprophylaxis and without a date limit on vaccination was therefore undertaken. There were 2381 studies identified of which two additional studies met the inclusion criteria. The summary risk ratio for chemoprophylaxis vs. no chemoprophylaxis (four studies) in the 30-day period after a case was 0·16 [95% confidence interval (CI) 0·04-0·64, P = 0·008]; the number needed to treat to prevent one subsequent case was 200 (95% CI 111-1000). A single quasi-randomized trial assessed the role of vaccination. The risk ratio for vaccination vs. no vaccination at 30 days was 0·11 (95% CI 0·01–2·07, P = 0·14). The results support the use of chemoprophylaxis to prevent subsequent cases of IMD in household contacts of a case. Conclusions about the use of vaccination could not be drawn.
Kochia is a troublesome weed throughout the western United States. Although
glyphosate effectively controls kochia, poor control was observed in several
no-till fields in Kansas. The objectives of this research were to evaluate
kochia populations response to glyphosate and examine the mechanism that
causes differential response to glyphosate. Glyphosate was applied at 0, 54,
109, 218, 435, 870, 1305, 1740, 3480, and 5220 g ae ha−1 on 10
kochia populations. In general, kochia populations differed in their
response to glyphosate. At 21 d after treatment, injury from glyphosate
applied at 870 g ha−1 range from 4 to 91%. In addition,
glyphosate rate required to cause 50% visible injury (GR50)
ranged from 470 to 2149 g ha−1. Differences in glyphosate
absorption and translocation and kochia mineral content were not sufficient
to explain differential kochia response to glyphosate.
We present evidence to show that changes in the Sun's equatorial rotation rate are synchronized with changes in its orbital motion about the barycentre of the Solar System. We propose that this synchronization is indicative of a spin–orbit coupling mechanism operating between the Jovian planets and the Sun. However, we are unable to suggest a plausible underlying physical cause for the coupling. Some researchers have proposed that it is the period of the meridional flow in the convective zone of the Sun that controls both the duration and strength of the Solar cycle. We postulate that the overall period of the meridional flow is set by the level of disruption to the flow that is caused by changes in Sun's equatorial rotation speed. Based on our claim that changes in the Sun's equatorial rotation rate are synchronized with changes in the Sun's orbital motion about the barycentre, we propose that the mean period for the Sun's meridional flow is set by a Synodic resonance between the flow period (∼22.3 yr), the overall 178.7-yr repetition period for the solar orbital motion, and the 19.86-yr synodic period of Jupiter and Saturn.
High-resolution spectroscopy and spectropolarimetry have been undertaken at the Anglo-Australian Telescope in order to identify suitable targets for magnetic studies of young Sun-like stars, for the proxy study of early solar evolution. This study involved the investigation of some variable late F- / early G-type Sun-like stars originally identified by the Hipparcos mission. Of the 38 stars observed for this study, HIP 31021, HIP 64732, HIP 73780 were found to be spectroscopic binary stars, while HIP 19072, HIP 67651 and HIP 75636 are also likely to be binaries and HIP 33111 could even be a triple system. Magnetic fields were detected on a number of the survey stars: HIP 21632, HIP 43720, HIP 48770, HIP 62517, HIP 71933, HIP 77144, HIP 89829, HIP 90899 and HIP 105388, making these stars good candidates for follow-up Zeeman Doppler imaging studies.
A high resolution record of water column temperatures was measured in a coastal meltwater pond on the McMurdo Ice Shelf, Antarctica. The maximum temperature gradient measured through the water column was 35°C, with an annual temperature range of 52.1°C within the pond. For most of the year the pond shows reverse temperature stratification with the lowest temperatures measured at the surface of the pond, with the exception of brief periods of normal stratification over winter caused by regional warming events. During freezing, the freezing front propagated downwards from the pond surface, excluding major ions and releasing large amounts of latent heat, both of which had a dramatic effect on the thermal and compositional evolution of the pond. Thawing is dominated by changes in surface air temperatures and the differential absorption of solar radiation. A new conceptual model of the physical freeze-thaw process has been developed that explains the presence of an ‘ice plug’ during melting, which reduces wind-induced mixing, forms a physical barrier to chemical processes, and encourages thermal and chemical stratification. It may also explain the persistence of anoxic and hydrogen sulphide bearing basal brines in summer stratified ponds that are otherwise fully oxidized.
The jaws of the marine worm Nereis sp. are made of protein fibers and are reinforced by zinc. Here we study a transverse section through the jaw using optical microscopy and nanoindentation. Optical microscopy images demonstrate a complex microstructure which includes channels that extend throughout the jaw. We suggest that these channels may be related to jaw remodeling. The mechanical results reveal spatial variations in both indentation hardness and reduced modulus. Specifically, the toothed side of the jaw (used for grasping food) is harder than the remainder of the jaw and the very exterior surface is hardest.
This descriptive study investigated an outbreak of hepatitis A virus (HAV) infection among injecting drug users (IDUs) and their contacts. Twenty-seven cases of acute HAV infection were identified in a 5-month period. Connections with the local injecting drug using (IDU) population were established for 25 of the cases of whom 14 admitted to injecting drug use. HAV RNA genotyping revealed two HAV variants, closely related to variants found in Scandinavian IDUs and in South East Asia. The study demonstrates that once HAV enters the IDU population extensive outbreaks are possible. We recommend that all IDUs should be tested for HAV and hepatitis B virus (HBV) infections and offered combined hepatitis A and B vaccines if non-immune.
Multi-photon excitation has been used in microscopy for nearly a decade, providing a number of demonstrated advantages over other methods for fluorescence imaging. Because excitation is achieved using longer, less energetic light, photodamage and photobleaching of the sample are reduced. Furthermore, since excitation occurs only at the focal point, this approach allows the practical collection of three-dimensionally resolved fluorescence images of live cells. However, due to the small two-photon cross-section of most fluorophores, pulsed lasers are required to generate detectable signal levels. This is due to the quadratic dependence of twophoton absorption on the instantaneous power of the laser. Typically, these lasers are pulsed at very high repetition frequencies, on the order of 106 pulses per second with pulse durations of a few hundreds of femtoseconds. For example, a titanium:sapphire (Ti:S) laser mode-locked at 76 Mhz can provide up to 100,000 watts of instantaneous power and is ideal for exciting two-photon events.
Analytical electron microscopy (AEM) has been employed to characterize the distribution of U(VI) on several mineral substrates, including standard kaolinite samples and weathered rock samples from Koongarra, Australia. Results of this study reveal that pre-existing impurity phases play a significant role in the uptake of U(VI) on standard kaolinite samples. Using a natural sample from the weathered zone of the Koongarra uranium deposit, we have also demonstrated that U(VI) sorption is controlled by iron oxyhydroxides (predominantly goethite) which constitute a small fraction of the sample. Limited sorption of U(VI) was observed on the clay minerals of this substrate. Uptake of U(VI) by goethite increases with total uranium content up to the point of uranium precipitation, after which it decreases dramatically. Uranium precipitation is indicated by the appearance of a uranyl oxyhydroxide phase.
Survivors from a nationally representative sample of elderly people originally screened in 1985 were reassessed in 1989 and again in 1993. On each occasion respondents were rated as cognitively impaired, borderline impaired or unimpaired (using a brief information/orientation scale), with the validity of these ratings assessed in subsequent clinical interviews. Where follow-up screening was not possible, information was derived from death certificates and hospital case-notes. Over 8 years (1985–93) the overall incidence rate per person–year at risk was 1·58%, giving age-specific rates of 0·72, 1·32, 1·63, 3·46, 2·55 and 1·41% for the age groups 65–69, 70–74, 75–79, 80–84, 85–89 and ≥ 90 respectively. Of 43 individuals classified at screening as borderline impaired in 1985 and 1989, 19 were diagnosed as demented at clinical interviews conducted within 16 weeks of screening. Four-year follow-ups among the remaining 24 showed that 15 had died, while 6 showed a worsened cognitive status. Controlling for both age and sex, aggregated 4-year mortality was significantly higher among those defined at screening in 1985 and 1989 as either impaired or borderline, when compared with the unimpaired.
Poly(γ-benzyl-L-glutamate) (PBLG) may be derivatized on its periphery by covalently attaching χ-active NLO chromophores at the termini of its sidechains and thereby give a new class of SHG materials. The inherent liquid crystalline properties of concentrated solutions of α-helical PBLG may be exploited to establish unique supramolecular structures prior to E-field poling. When PBLG is derivatized at its N-terminus with lipoic acid, it will self-assemble on gold to give a thin film. Angle-dependent XPS, ellipsometry, contact angle measurements, and grazing angle IR reflection-absorption spectroscopy give quantitative information about the orientation of the polypeptide α-helices relative to the substrate surface. Consequently, polypeptides, in particular, Merrifield-synthesized or recombinant DNA-expressed synthetic polypeptides, present a novel fabrication route to thin films wherein molecular-engineered functionalities (chemical, electrical, or optically active species) may be encoded into the macromolecule's primary structure and subsequently expressed spatially via the spontaneous self-organization of these rod-like polymers.
Angular-resolved ESCA was used to study single cadmium arachidate monolayers transferred to Si (100) wafers by the Langmuir-Blodgett technique. We find the monolayers to be of high integrity with respect to those defects which enhance the escape probability of substrate photoelectrons through the overlayer. The inelastic mean-free pathlengths of Si (2p) and C (1s) electrons were calculated to be 49±6 Å and 45±6 Å for the kinetic energies of 1388 eV and 1202 eV, respectively. The overall ordering of the hydrocarbon chains is less than for alkane thiols assembled on noble metals. We find that the precision of the Tyler algorithm to deconvolute angular-resolved ESCA data into depth profiles is accurate within 10% for predicting the thickness of the hydrocarbon overlayer but less precise for intermediate layers.
The modelling of the aggregation kinetics of iron oxides has been succesful in predicting the increase in aggregate size as determined by dynamic light scattering measurements. The aggregates were found to exhibit fractal behaviour with fractal dimensions obtained from the scattering exponent in static light scattering studies dependent on the aggregation mechanism and ranging from 2.3 for rapid (diffusion limited) to 2.8 for slow (reaction limited) aggregation. Polydispersity and restructuring of aggregates were found not to affect the relationship between scattering exponent and aggregate fractal dimension. Excellent correspondence over a range of temperatures and ionic strengths has been obtained between results of sizing experiments using dynamic light scattering and sizes predicted using a modified Smoluchowski model incorporating fractal dimensions.