Prodigious degassing of a billion years of accumulated radiogenic helium at Yellowstone.

Helium is used as a critical tracer throughout the Earth sciences, where its relatively simple isotopic systematics is used to trace degassing from the mantle, to date groundwater and to time the rise of continents. The hydrothermal system at Yellowstone National Park is famous for its high helium-3/helium-4 isotope ratio, commonly cited as evidence for a deep mantle source for the Yellowstone hotspot. However, much of the helium emitted from this region is actually radiogenic helium-4 produced within the crust by α-decay of uranium and thorium. Here we show, by combining gas emission rates with chemistry and isotopic analyses, that crustal helium-4 emission rates from Yellowstone exceed (by orders of magnitude) any conceivable rate of generation within the crust. It seems that helium has accumulated for (at least) many hundreds of millions of years in Archaean (more than 2.5 billion years old) cratonic rocks beneath Yellowstone, only to be liberated over the past two million years by intense crustal metamorphism induced by the Yellowstone hotspot. Our results demonstrate the extremes in variability of crustal helium efflux on geologic timescales and imply crustal-scale open-system behaviour of helium in tectonically and magmatically active regions.

A dedicated high-quality service for the management of patients with an inherited risk of colorectal cancer.

AIM: To demonstrate the quality improvement associated with the implementation of a specialist family history of bowel cancer service in secondary care. METHOD: The following outcomes were assessed: (1) adherence to the British Society of Gastroenterology (BSG) guidelines for colonoscopic surveillance of individuals with a family history of colorectal cancer (CRC); (2) adherence to the revised Bethesda criteria for the identification of CRC patients with suspected Lynch syndrome; (3) identification of inherited syndromes with increased CRC risk; and (4) colonoscopic adenoma detection rate. Data were collected for a 21-month period before and after the establishment of this service for all patients who underwent colonoscopic surveillance for a family history of CRC and all patients newly diagnosed with CRC. Analyses compared the number of colonoscopies performed that were not indicated by BSG guidelines, the average number of years early that patients were screened, the adenoma detection rate and the rate of tumour testing for mismatch repair genes before and after the implementation of the service. RESULTS: Following the establishment of the service there was a reduction in the number of colonoscopies not indicated by BSG guidelines (39.6% before and 5.8% after, P < 0.001, chi-square test) and surveillance colonoscopy took place at a more appropriate age (10.6 years too early before and 5.9 years early after, P = 0.01, t-test). There was an increased adenoma detection rate (17% before and 31.9% after, P < 0.01, chi-square test) and increased tumour MMR testing (3.4% before and 91.8% after, P < 0.01, chi-square test). CONCLUSION: The introduction of a family history of bowel cancer service results in improved patient care through improved adherence to guidelines for colonoscopic surveillance and increased cancer detection rates.

High Performance Bi-2212 Round Wires Made with Recent Powders.

Multifilamentary Bi2Sr2CaCu2Ox (Bi-2212) wire made by the powder-in-tube technique is the only high temperature superconductor made in the round shape preferred by magnet builders. The critical current density (J C ) of Bi-2212 round wire was improved significantly by the development of overpressure heat treatment in the past few years. Bi-2212 wire is commercially available in multiple architectures and kilometer-long pieces and a very promising conductor for very high field NMR and accelerator magnets. We studied the effects of precursor powder and heat treatment conditions on the superconducting properties and microstructure of recent Bi-2212 wires. Short samples of recent wire with optimized overpressure processing showed J C (4.2 K, 15 T) = 6640 A/mm2 and J C (4.2 K, 30 T) = 4670 A/mm2, which correspond to engineering critical current densities J E (4.2 K, 15 T) = 1320 A/mm2 and J E (4.2 K, 30 T) = 930 A/mm2.

Impact of previous hepatitis B infection on the clinical outcomes from chronic hepatitis C? A population-level analysis.

Chronic coinfection with hepatitis C virus (HCV) and hepatitis B virus (HBV) is associated with adverse liver outcomes. The clinical impact of previous HBV infection on liver disease in HCV infection is unknown. We aimed at determining any association of previous HBV infection with liver outcomes using antibodies to the hepatitis B core antigen (HBcAb) positivity as a marker of exposure. The Scottish Hepatitis C Clinical Database containing data for all patients attending HCV clinics in participating health boards was linked to the HBV diagnostic registry and mortality data from Information Services Division, Scotland. Survival analyses with competing risks were constructed for time from the first appointment to decompensated cirrhosis, hepatocellular carcinoma (HCC) and liver-related mortality. Records of 8513 chronic HCV patients were included in the analyses (87 HBcAb positive and HBV surface antigen [HBsAg] positive, 1577 HBcAb positive and HBsAg negative, and 6849 HBcAb negative). Multivariate cause-specific proportional hazards models showed previous HBV infection (HBcAb positive and HBsAg negative) significantly increased the risks of decompensated cirrhosis (hazard ratio [HR]: 1.29, 95% CI: 1.01-1.65) and HCC (HR: 1.64, 95% CI: 1.09-2.49), but not liver-related death (HR: 1.02, 95% CI: 0.80-1.30). This is the largest study to date showing an association between previous HBV infection and certain adverse liver outcomes in HCV infection. Our analyses add significantly to evidence which suggests that HBV infection adversely affects liver health despite apparent clearance. This has important implications for HBV vaccination policy and indications for prioritization of HCV therapy.

A bioluminescent Pseudomonas aeruginosa wound model reveals increased mortality of type 1 diabetic mice to biofilm infection.

OBJECTIVE: To examine how bacterial biofilms, as contributing factors in the delayed closure of chronic wounds in patients with diabetes, affect the healing process. METHOD: We used daily microscopic imaging and the IVIS Spectrum in vivo imaging system to monitor biofilm infections of bioluminescent Pseudomonas aeruginosa and evaluate healing in non-diabetic and streptozotocin-induced diabetic mice. RESULTS: Our studies determined that diabetes alone did not affect the rate of healing of full-depth murine back wounds compared with non-diabetic mice. The application of mature biofilms to the wounds significantly decreased the rate of healing compared with non-infected wounds for both non-diabetic as well as diabetic mice. Diabetic mice were also more severely affected by biofilms displaying elevated pus production, higher mortality rates and statistically significant increase in wound depth, granulation/fibrosis and biofilm presence. Introduction of a mutant Pseudomonas aeruginosa capable of producing high concentrations of cyclic di-GMP did not result in increased persistence in either diabetic or non-diabetic animals compared with the wild type strain. CONCLUSION: Understanding the interplay between diabetes and biofilms may lead to novel treatments and better clinical management of chronic wounds.

Does the EarPopper(®) device improve hearing outcomes in children with persistent otitis media with effusion? A randomised single-blinded controlled trial.

OBJECTIVE: To provide an independent evaluation of the efficacy and safety of the EarPopper(®) in improving hearing outcomes in children with otitis media with effusion (OME) and reducing the ventilation tube insertion rate. STUDY DESIGN: Randomised single-blinded controlled trial. SETTING: The Ear Nose and Throat Department of a district general hospital (Heatherwood and Wexham Park). PARTICIPANTS AND METHODS: Twenty-nine children aged between 4 and 11 years diagnosed with persistent OME lasting at least 3 months with an average hearing of 25 dBHL or worse in the better ear were randomised to a treatment or control group for 7 weeks using random computer-generated codes. Syndromic children, children with developmental delay, previous grommets and cleft palate were excluded. The audiologists were blinded at the final post-treatment audiogram. RESULTS: After the seven-week period, the mean improvement in air conduction across all frequencies was 10.9 dBHL in the treatment group (P < 0.001) and 3.6 dBHL in the control group (P = 0.201). At every frequency, the treatment group had larger improvements in air conduction, the largest being at 4 kHz where the mean air conduction in both ears improved by 14.8 dBHL. Compliance with the EarPopper(®) was over 90%, the only side-effect reported being discomfort in the ears immediately after use which resolved and did not affect compliance. The ventilation tube insertion rate was 53.3% in the treatment group and 78.6% in the control group. Median follow-up time for all patients is 47.7 months. CONCLUSION: Our study shows that the EarPopper(®) is a safe, effective treatment option for children with hearing loss from persistent OME, and it reduces the rate of ventilation tube insertion. More studies with larger sample sizes are required to support our findings.

Randomized controlled trial of asthma risk with paracetamol use in infancy--a feasibility study.

BACKGROUND: There is non-experimental evidence that paracetamol (acetaminophen) use may increase the risk of developing asthma. However, numerous methodological issues need to be resolved before undertaking a randomized controlled trial to investigate this hypothesis. OBJECTIVE: To establish the feasibility of a randomized controlled trial of liberal paracetamol as usually given by parents/guardians vs. a comparator (restricted paracetamol in accordance with WHO guidelines, ibuprofen or placebo), and childhood asthma risk. METHODS: Questionnaires were completed by parents/guardians of infants admitted to Wellington Hospital with bronchiolitis to assess views about comparator treatments. Subsequently, infants of parents/guardians who provided informed consent were randomized to restricted or liberal paracetamol use for 3 months with paracetamol use recorded. RESULTS: Of 120 eligible participants, 72 (60%) parents/guardians completed the questionnaire. Ibuprofen, restricted paracetamol and placebo were acceptable to 42 (58%), 29 (40%) and 9 (12%) parents/guardians, respectively. 36 (30%) infants were randomized to restricted or liberal paracetamol. Paracetamol use was greater for the liberal vs. restricted group for reported [Hodges-Lehmann estimator of difference 0.94 mg/kg/day (95% CI 0.2-3.52), P = 0.02] and measured use [Hodges-Lehmann estimator of difference 2.11 mg/kg/day (95% CI 0.9-4.18), P = 0.004]. The median reported and measured use of paracetamol was 2.0-fold and 3.5-fold greater in the liberal vs. restricted group. CONCLUSIONS AND CLINICAL RELEVANCE: Although separation in paracetamol dosing is likely to be achieved with a liberal vs. restricted paracetamol regime, ibuprofen is the preferred comparator treatment in the proposed RCT of paracetamol use and risk of asthma in childhood.

Scaling of geochemical reaction rates via advective solute transport.

Transport in porous media is quite complex, and still yields occasional surprises. In geological porous media, the rate at which chemical reactions (e.g., weathering and dissolution) occur is found to diminish by orders of magnitude with increasing time or distance. The temporal rates of laboratory experiments and field observations differ, and extrapolating from laboratory experiments (in months) to field rates (in millions of years) can lead to order-of-magnitude errors. The reactions are transport-limited, but characterizing them using standard solute transport expressions can yield results in agreement with experiment only if spurious assumptions and parameters are introduced. We previously developed a theory of non-reactive solute transport based on applying critical path analysis to the cluster statistics of percolation. The fractal structure of the clusters can be used to generate solute distributions in both time and space. Solute velocities calculated from the temporal evolution of that distribution have the same time dependence as reaction-rate scaling in a wide range of field studies and laboratory experiments, covering some 10 decades in time. The present theory thus both explains a wide range of experiments, and also predicts changes in the scaling behavior in individual systems with increasing time and/or length scales. No other theory captures these variations in scaling by invoking a single physical mechanism. Because the successfully predicted chemical reactions include known results for silicate weathering rates, our theory provides a framework for understanding changes in the global carbon cycle, including its effects on extinctions, climate change, soil production, and denudation rates. It further provides a basis for understanding the fundamental time scales of hydrology and shallow geochemistry, as well as the basis of industrial agriculture.

Environmental relative moldiness index and associations with home characteristics and infant wheeze.

Possible relationships between mold contamination, as described by the Environmental Relative Moldiness Index (ERMI), home characteristics, and the development of wheeze in the first year of life were evaluated among a cohort of urban infants (n = 103) in Syracuse, New York. Pregnant women with a history of asthma were recruited in 2001-2002 for the "Assessment of Urban Dwellings for Indoor Toxics" (AUDIT) study. When the infants were approximately 3 months of age, a home inspection was carried out and indoor environmental samples collected, including vacuumed house dust. ERMI levels in the Syracuse cohort homes were higher than the U.S. average, with an overall mean of 11.4. ERMI levels were significantly higher in homes with visible water problems (p = 0.023) and visible mold (p = 0.023). ERMI levels in apartments were significantly lower than the values measured in houses (p = 0.0003). While infants experiencing wheeze (38%) tended to live in homes with higher ERMI values than those without wheeze (ERMI values of 12.3 and 10.9, respectively), the differences did not reach statistical significance. A subset analysis limited to infants with living room samples who remained in the same home during the study (n = 25) was suggestive of an association between higher ERMI values and wheeze (p = 0.10). In summary, the ERMI is a standardized metric which allows for comparison of moldiness levels in homes across studies and regions in the United States. ERMI levels in Syracuse homes were skewed to the high end of the national scale. Higher ERMI levels were indicators of water problems, mold, and type of housing.

Sexual dimorphism of human vallate papillae: an in vivo study of normative morphology.

The perimeters of vallate papillae (VP) house approximately half of the taste buds on the human tongue. However, little information exists regarding perimeter measurements of VP. Likewise, great diversity exists among reports of the number of VP and diameter of VP, in general. The research presents an analysis of the perimeters, counts, and diameters of VP in vivo. Endoscopic examination was performed on 79 individuals (40 females, 39 males) between 18 and 26 years of age. A total of 583 VP were counted, 565 of which were able to be measured. Data revealed a statistically significant difference between male and female VP count (t(75.6) = 4.5; p = 0.00003). Females had, on average, 2.22 more VP than males. Males were found to have larger mean VP diameter per person and mean VP perimeter per person than females (t(58.9) = -2.4; p = 0.021 and t(59.3) = -2.4; p = 0.019, respectively). The report demonstrates that VP are sexually dimorphic at the gross anatomical level.

Electronic structure of spinel-type nitride compounds Si3N4, Ge3N4, and Sn3N4 with tunable band gaps: application to light emitting diodes.

In this Letter using experimental and theoretical methods, we show that the solid solutions of group 14 nitrides having spinel structure (γ-M3N4 where M=Si, Ge, Sn) exhibit mainly direct electronic band gaps with values that span the entire visible wavelength region, making these hard and thermally stable materials suitable for optoelectronic devices and, in particular, lighting applications. Using the simulated band structure, we also calculate the exciton binding energy. The combination of large exciton binding energies and the tunable electronic band gaps in the visible range makes these binary spinel nitrides and their solid solutions a new class of multifunctional materials with optoelectronic properties that can be engineered to suit the desired application.

Symptoms of heat illness in surface mine workers.

OBJECTIVE: To assess the symptoms of heat illness experienced by surface mine workers. METHODS: Ninety-one surface mine workers across three mine sites in northern Australia completed a heat stress questionnaire evaluating their symptoms for heat illness. A cohort of 56 underground mine workers also participated for comparative purposes. Participants were allocated into asymptomatic, minor or moderate heat illness categories depending on the number of symptoms they reported. Participants also reported the frequency of symptom experience, as well as their hydration status (average urine colour). RESULTS: Heat illness symptoms were experienced by 87 and 79 % of surface and underground mine workers, respectively (p = 0.189), with 81-82 % of the symptoms reported being experienced by miners on more than one occasion. The majority (56 %) of surface workers were classified as experiencing minor heat illness symptoms, with a further 31 % classed as moderate; 13 % were asymptomatic. A similar distribution of heat illness classification was observed among underground miners (p = 0.420). Only 29 % of surface miners were considered well hydrated, with 61 % minimally dehydrated and 10 % significantly dehydrated, proportions that were similar among underground miners (p = 0.186). Heat illness category was significantly related to hydration status (p = 0.039) among surface mine workers, but only a trend was observed when data from surface and underground miners was pooled (p = 0.073). Compared to asymptomatic surface mine workers, the relative risk of experiencing minor and moderate symptoms of heat illness was 1.5 and 1.6, respectively, when minimally dehydrated. CONCLUSIONS: These findings show that surface mine workers routinely experience symptoms of heat illness and highlight that control measures are required to prevent symptoms progressing to medical cases of heat exhaustion or heat stroke.

Tranexamic acid in sinus and nasal surgery: an up-to-date meta-analysis.

OBJECTIVE: There are gaps within current meta-analyses looking at the effects of tranexamic acid on sino-nasal surgery. This study aimed to update and summarise all current available evidence on the use of tranexamic acid in sino-nasal surgery. METHOD: A literature search was performed using four medical databases, Cochrane Library, Embase, Medline and PubMed. Data analysis was performed using dedicated meta-analysis software Review Manager (Revman). RESULTS: Thirteen studies were included in the meta-analysis. The amount of blood loss and duration of surgery in tranexamic acid groups was statistically lower than placebo for both sinus and nasal surgery. Tranexamic acid improves the surgical field quality in sinus surgery but worsens the field in nasal surgery. Topical or intravenous administration of tranexamic acid in sinus surgery reduces blood loss, duration of surgery and improves the quality of the surgical field. CONCLUSION: This study suggests that the use of tranexamic acid in sinus surgery reduces blood loss, decreases surgical duration and improves surgical field quality.

Methicillin-resistant Staphylococcus aureus in Northeastern Scotland in 2003 to 2007: evolving strain distribution and resistance patterns.

This study explored strain distribution and resistance patterns of methicillin-resistant Staphylococcus aureus (MRSA) over a 5-year period in northeastern Scotland. We noted a shift in the relative rates of epidemic strains and an increase in community-associated strains. Use of oral antibiotics to eradicate throat carriage may have contributed to trimethoprim resistance, which was observed to increase 10-fold.

Non-psychiatric health problems among psychiatric inpatients with intellectual disabilities.

BACKGROUND: Physical distress resulting from medical problems has been found to cause increased behaviour problems in patients with intellectual disabilities (ID). Despite this fact, little has been documented on the medical problems of individuals with ID admitted for inpatient psychiatric care. We conducted an exploratory investigation based on a retrospective chart review of the medical problems and medications for 198 people with ID who had been admitted to a specialised inpatient psychiatric unit. Most patients were referred for admission because of aggressive, disruptive and self-injurious behaviours. The average length of stay was 17.6 days. METHODS: We tallied the total number of medical problems and medications listed in the patients' discharge summaries. Because longer stays are disruptive, costly and associated with greater overall impairment, we examined the relationship between length of stay and frequency of discharge medical diagnoses. We also assessed whether or not the number of psychoactive medications correlated with the number of medical diagnoses. The effects of other demographic and diagnostic variables on rates of medical diagnoses and medications were also evaluated, including gender, age group (16-25, 26-45, 46-60, >60), level of ID (mild, moderate or severe ID) and diagnosis of an autism spectrum disorder or Down syndrome (DS). RESULTS: Inpatients with a higher number of medical diagnoses had longer lengths of stay (Spearman r = +0.32, P < 0.0001). There was a significant correlation between number of psychoactive medications and number of medical problems (Spearman r = +0.32, P < 0.0001). The most frequent medical comorbidity was constipation, reported in 60% of the inpatients (n = 118), while gastro-esophageal reflux disease was identified in 38% (n = 75). Older inpatients had an increased number of medical problems, as might be expected, but a diagnosis of an autism spectrum disorder, gender and level of ID had no detectible effect on rates of either medical diagnoses or medications. There were only 13 inpatients with DS; in this modest sample, it was found that they had higher rates of osteoarthritis, cardiac problems, hearing loss, hypothyroidism and sleep apnoea than peers without DS, as is consistent with previous findings on overrepresented conditions in this trisomy. CONCLUSIONS: In the present study, individuals with ID admitted for inpatient psychiatric care exhibited high rates of medical problems, and these were associated with duration of inpatient stay. Based on these findings, further investigation of the effects of medical problems on behaviour among individuals with ID admitted for inpatient psychiatric care is warranted.

Time-use diaries are acceptable to parents with a disabled preschool child and are helpful in understanding families' daily lives.

BACKGROUND: In order to provide services for children with disabilities which are family focused, strengthening and enabling families in addition to meeting the child's identified needs, it is important to understand families' lives. This study investigates whether time-use diaries can provide an acceptable tool to explore the daily lives of parents with a disabled child. METHODS: A precoded time-use diary divided into 15 min time slots was designed. Father-mother pairs with a preschool child with either autism (ASD) or technology dependence (TD) were asked to complete a 7-day diary independently, over the same time period. Each parent was then interviewed separately to ascertain their experiences of using the diary. Participants were identified through their involvement with a Child Development Centre. RESULTS: Twenty-six parents (13 father-mother pairs) were invited to participate. Eighteen parents agreed to be involved; 16 completed the diaries and interviews. Three father-mother pairs in the ASD group and one father-mother pair in the TD group declined to be involved. One father-mother pair from the TD group withdrew from the study. Of the 18 parents who agreed to participate, 15 found the diaries acceptable and either easy or straightforward to complete. One parent with dyslexia and one who described himself as a non-reader completed the diaries successfully, finding the colour coding helpful. Parents spent between 10 and 60 min a day completing the diaries, with the median 20-30 min. The diaries provided information on the total amount of time spent on different activities and how much time parents spent together, with their other children, at home or elsewhere. CONCLUSION: The time-use diaries designed for this study were acceptable to the majority of parents and provided detailed information about their daily lives.

A change in clinical practice for aural foreign bodies - what we learnt from the coronavirus disease 2019 pandemic.

OBJECTIVE: This case series, conducted during the coronavirus disease 2019 pandemic, investigates the impact of leaving aural foreign bodies in situ for a prolonged period of time, including the risk of complications and success rates of subsequent removal attempts. METHOD: A retrospective study of aural foreign body referrals over a six-month period was carried out. RESULTS: Thirty-four patients with 35 foreign bodies were identified (6 organic and 29 inorganic). The duration of foreign bodies left in situ ranged from 1 to 78 days. Four patients suffered from traumatic removal upon initial attempts. First attempts made by non-ENT specialists (68.8 per cent) all failed and were associated with a high risk of trauma (36.4 per cent). CONCLUSION: Because of the coronavirus disease 2019 pandemic, this is the first case series to specifically investigate the relationship between the duration of aural foreign bodies left in situ and the risk of complications. Our data suggest that prolonged duration does not increase the incidence of complications.

DNA sequence and analysis of human chromosome 9.

Chromosome 9 is highly structurally polymorphic. It contains the largest autosomal block of heterochromatin, which is heteromorphic in 6-8% of humans, whereas pericentric inversions occur in more than 1% of the population. The finished euchromatic sequence of chromosome 9 comprises 109,044,351 base pairs and represents >99.6% of the region. Analysis of the sequence reveals many intra- and interchromosomal duplications, including segmental duplications adjacent to both the centromere and the large heterochromatic block. We have annotated 1,149 genes, including genes implicated in male-to-female sex reversal, cancer and neurodegenerative disease, and 426 pseudogenes. The chromosome contains the largest interferon gene cluster in the human genome. There is also a region of exceptionally high gene and G + C content including genes paralogous to those in the major histocompatibility complex. We have also detected recently duplicated genes that exhibit different rates of sequence divergence, presumably reflecting natural selection.

Injuries during transition periods across the year in pre-professional and professional ballet and contemporary dancers: A systematic review and meta-analysis.

OBJECTIVE: To consider the association of injuries with transition periods in the dance year, i.e., when dancers return at the start of the year, and when they transition from rehearsal to performance periods. METHODS: Six electronic databases were searched to November 2019. All English language peer-reviewed studies, of any study design investigating ballet and contemporary pre-professional and professional dance populations were included. Only those studies reporting on the timing of injury were included. RESULTS: Fifteen cohort and two case-series studies were included. A meta-analysis of seven studies revealed the rate of injuries to be significantly higher for the second and third months (1.52; 95% confidence interval [CI]:1.11-2.08; 1.26; 95%CI:1.07-1.48 respectively) after the return to dance. Two further studies report more injuries up to Week 13 of the year. One study showed an increase in injured dancers at three and four weeks after transition from rehearsals to a performance season. Four studies show an increase in injuries at performance times. CONCLUSIONS: Meta-analyses of seven studies shows the second and third months after returning to dance have a significantly higher rate of injuries. More research is needed to quantify training loads in dance. Practitioners should be cognisant of the higher injury rates during periods of transition and consider modifying load, as it is a potential contributing factor.