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Next generation high-power laser facilities are expected to generate hundreds-of-MeV proton beams and operate at multi-Hz repetition rates, presenting opportunities for medical, industrial and scientific applications requiring bright pulses of energetic ions. Characterizing the spectro-spatial profile of these ions at high repetition rates in the harsh radiation environments created by laser–plasma interactions remains challenging but is paramount for further source development. To address this, we present a compact scintillating fiber imaging spectrometer based on the tomographic reconstruction of proton energy deposition in a layered fiber array. Modeling indicates that spatial resolution of approximately 1 mm and energy resolution of less than 10% at proton energies of more than 20 MeV are readily achievable with existing 100 μm diameter fibers. Measurements with a prototype beam-profile monitor using 500 μm fibers demonstrate active readouts with invulnerability to electromagnetic pulses, and less than 100 Gy sensitivity. The performance of the full instrument concept is explored with Monte Carlo simulations, accurately reconstructing a proton beam with a multiple-component spectro-spatial profile.
NASA’s all-sky survey mission, the Transiting Exoplanet Survey Satellite (TESS), is specifically engineered to detect exoplanets that transit bright stars. Thus far, TESS has successfully identified approximately 400 transiting exoplanets, in addition to roughly 6 000 candidate exoplanets pending confirmation. In this study, we present the results of our ongoing project, the Validation of Transiting Exoplanets using Statistical Tools (VaTEST). Our dedicated effort is focused on the confirmation and characterisation of new exoplanets through the application of statistical validation tools. Through a combination of ground-based telescope data, high-resolution imaging, and the utilisation of the statistical validation tool known as TRICERATOPS, we have successfully discovered eight potential super-Earths. These planets bear the designations: TOI-238b (1.61$^{+0.09} _{-0.10}$ R$_\oplus$), TOI-771b (1.42$^{+0.11} _{-0.09}$ R$_\oplus$), TOI-871b (1.66$^{+0.11} _{-0.11}$ R$_\oplus$), TOI-1467b (1.83$^{+0.16} _{-0.15}$ R$_\oplus$), TOI-1739b (1.69$^{+0.10} _{-0.08}$ R$_\oplus$), TOI-2068b (1.82$^{+0.16} _{-0.15}$ R$_\oplus$), TOI-4559b (1.42$^{+0.13} _{-0.11}$ R$_\oplus$), and TOI-5799b (1.62$^{+0.19} _{-0.13}$ R$_\oplus$). Among all these planets, six of them fall within the region known as ‘keystone planets’, which makes them particularly interesting for study. Based on the location of TOI-771b and TOI-4559b below the radius valley we characterised them as likely super-Earths, though radial velocity mass measurements for these planets will provide more details about their characterisation. It is noteworthy that planets within the size range investigated herein are absent from our own solar system, making their study crucial for gaining insights into the evolutionary stages between Earth and Neptune.
We describe here efforts to create and study magnetized electron–positron pair plasmas, the existence of which in astrophysical environments is well-established. Laboratory incarnations of such systems are becoming ever more possible due to novel approaches and techniques in plasma, beam and laser physics. Traditional magnetized plasmas studied to date, both in nature and in the laboratory, exhibit a host of different wave types, many of which are generically unstable and evolve into turbulence or violent instabilities. This complexity and the instability of these waves stem to a large degree from the difference in mass between the positively and the negatively charged species: the ions and the electrons. The mass symmetry of pair plasmas, on the other hand, results in unique behaviour, a topic that has been intensively studied theoretically and numerically for decades, but experimental studies are still in the early stages of development. A levitated dipole device is now under construction to study magnetized low-energy, short-Debye-length electron–positron plasmas; this experiment, as well as a stellarator device that is in the planning stage, will be fuelled by a reactor-based positron source and make use of state-of-the-art positron cooling and storage techniques. Relativistic pair plasmas with very different parameters will be created using pair production resulting from intense laser–matter interactions and will be confined in a high-field mirror configuration. We highlight the differences between and similarities among these approaches, and discuss the unique physics insights that can be gained by these studies.
We describe system verification tests and early science results from the pulsar processor (PTUSE) developed for the newly commissioned 64-dish SARAO MeerKAT radio telescope in South Africa. MeerKAT is a high-gain (
${\sim}2.8\,\mbox{K Jy}^{-1}$
) low-system temperature (
${\sim}18\,\mbox{K at }20\,\mbox{cm}$
) radio array that currently operates at 580–1 670 MHz and can produce tied-array beams suitable for pulsar observations. This paper presents results from the MeerTime Large Survey Project and commissioning tests with PTUSE. Highlights include observations of the double pulsar
$\mbox{J}0737{-}3039\mbox{A}$
, pulse profiles from 34 millisecond pulsars (MSPs) from a single 2.5-h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR
$\mbox{J}0540{-}6919$
, and nulling identified in the slow pulsar PSR J0633–2015. One of the key design specifications for MeerKAT was absolute timing errors of less than 5 ns using their novel precise time system. Our timing of two bright MSPs confirm that MeerKAT delivers exceptional timing. PSR
$\mbox{J}2241{-}5236$
exhibits a jitter limit of
$<4\,\mbox{ns h}^{-1}$
whilst timing of PSR
$\mbox{J}1909{-}3744$
over almost 11 months yields an rms residual of 66 ns with only 4 min integrations. Our results confirm that the MeerKAT is an exceptional pulsar telescope. The array can be split into four separate sub-arrays to time over 1 000 pulsars per day and the future deployment of S-band (1 750–3 500 MHz) receivers will further enhance its capabilities.
The objective of this study was to systematically assess the literature regarding postnatal healthcare utilization and barriers/facilitators of healthcare in neonatal abstinence syndrome (NAS) children.
Methods:
A systematic search was performed in PubMed, Cochrane Database of Systematic Reviews, PsychINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Web of Science to identify peer-reviewed research. Eligible studies were peer-reviewed articles reporting on broad aspects of primary and specialty healthcare utilization and access in NAS children. Three investigators independently reviewed all articles and extracted data. Study bias was assessed using the Newcastle–Ottawa Assessment Scale and the National Institute of Health Study Quality Assessment Tool.
Results:
This review identified 14 articles that met criteria. NAS children have poorer outpatient appointment adherence and have a higher rate of being lost to follow-up. These children have overall poorer health indicated by a significantly higher risk of ER visits, hospital readmission, and early childhood mortality compared with non-NAS infants. Intensive multidisciplinary support provided through outpatient weaning programs facilitates healthcare utilization and could serve as a model that could be applied to other healthcare fields to improve the health among this population.
Conclusions:
This review investigated the difficulties in accessing outpatient care as well as the utilization of such care for NAS infants. NAS infants tend to have decreased access to and utilization of outpatient healthcare following hospital birth discharge. Outpatient weaning programs have proven to be effective; however, these programs require intensive resources and care coordination that has yet to be implemented into other healthcare areas for NAS children.
There is a long history of exploitation of the South American river turtle Podocnemis expansa. Conservation efforts for this species started in the 1960s but best practices were not established, and population trends and the number of nesting females protected remained unknown. In 2014 we formed a working group to discuss conservation strategies and to compile population data across the species’ range. We analysed the spatial pattern of its abundance in relation to human and natural factors using multiple regression analyses. We found that > 85 conservation programmes are protecting 147,000 nesting females, primarily in Brazil. The top six sites harbour > 100,000 females and should be prioritized for conservation action. Abundance declines with latitude and we found no evidence of human pressure on current turtle abundance patterns. It is presently not possible to estimate the global population trend because the species is not monitored continuously across the Amazon basin. The number of females is increasing at some localities and decreasing at others. However, the current size of the protected population is well below the historical population size estimated from past levels of human consumption, which demonstrates the need for concerted global conservation action. The data and management recommendations compiled here provide the basis for a regional monitoring programme among South American countries.
Quantifying the physical mechanisms responsible for the transport of sediments, nutrients and pollutants in the abyssal sea is a long-standing problem, with internal waves regularly invoked as the relevant mechanism for particle advection near the sea bottom. This study focuses on internal-wave-induced particle transport in the vicinity of (almost) vertical walls. We report a series of laboratory experiments revealing that particles sinking slowly through a monochromatic internal wave beam experience significant horizontal advection. Extending the theoretical analysis by Beckebanze et al. (J. Fluid Mech., vol. 841, 2018, pp. 614–635), we attribute the observed particle advection to a peculiar and previously unrecognized streaming mechanism in the stratified boundary layer originating at the lateral walls. This vertical boundary layer streaming mechanism is most efficient for significantly inclined wave beams, when vertical and horizontal velocity components are of comparable magnitude. We find good agreement between our theoretical prediction and experimental results.
Introduction: Emergency department (ED) providers are frequently challenged with how best to treat acute pain in older patients, specifically when non-opioid analgesics are insufficient or contraindicated. Studies have documented older patients presenting to the ED with painful conditions are less likely to receive pain medications than younger patients, and this inadequate pain control has been associated with increased risk of delirium and longer hospital stays. As there are no guidelines informing best practice of analgesia in the older adult population, emergency physicians often report uncertainty regarding the ideal choice of opioid analgesic. The objective of this study was to compare the efficacy of opioid analgesics for acute pain in older adults (70 years) in the ED. Methods: Electronic searches of Medline, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and CINAHL were conducted and reference lists were hand-searched. Randomized controlled trials (RCTs) comparing the efficacy of 2 or more opioid analgesics for acute pain in older patients (70 years) in ambulatory settings (i.e., EDs, clinics) were included. Two reviewers independently screened abstracts, assessed quality of the studies, and extracted data. Results: After screening titles and abstracts of 1297 citations, the full-texts of 63 studies were reviewed, and 1 study met the inclusion criteria. This study allocated patients to receive either single dose of 0.0075-mg/kg IV hydromorphone versus 0.05-mg IV morphine and found no clinical or statistical difference between the two treatments in older adults presenting to an urban academic ED with acute, severe pain. Conclusion: The lack of published research in this area demonstrates a significant gap in the existing knowledge of the comparative efficacy of opioid analgesics in this growing patient population and that well-designed RCTs are urgently needed.
A high Ca intake has been recommended for osteoporosis prevention; however, little research has examined the relationship between dietary Ca and bone health in men. We examined associations between dietary Ca intake, bone mineral density (BMD) and change in BMD at the total body, hip and spine over 2 years in a cohort of men (mean age 57 years, BMI 26 kg/m2) from a trial. Data from the total cohort (n 323) were used in the analysis of Ca intake and BMD at baseline, and data from the placebo group (n 99) were used in the longitudinal analysis of Ca intake and change in BMD. Parathyroid hormone (PTH) and the markers of bone turnover serum total alkaline phosphatase activity, serum C-telopeptide and serum procollagen type-1 N-terminal propeptide were measured in a subset of participants at baseline (n 150), and associations with dietary Ca at baseline were examined. Mean Ca intake was 870 mg/d. Baseline BMD was not related to dietary Ca intake at any site, before or after adjustment for covariables. Similarly, bone loss over 2 years was not related to Ca intake at any site, before or after adjustment. Dietary Ca intake was inversely correlated with PTH at baseline (r −0·19, P=0·02), but was not associated with the markers of bone turnover. BMD and rates of bone loss were unrelated to Ca intake in these men. This suggests that strategies to increase Ca intake are unlikely to impact on the prevalence of and morbidity from male osteoporosis.
Measurement error in self-reported total sugars intake may obscure associations between sugars consumption and health outcomes, and the sum of 24 h urinary sucrose and fructose may serve as a predictive biomarker of total sugars intake.
Design
The Study of Latinos: Nutrition & Physical Activity Assessment Study (SOLNAS) was an ancillary study to the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) cohort. Doubly labelled water and 24 h urinary sucrose and fructose were used as biomarkers of energy and sugars intake, respectively. Participants’ diets were assessed by up to three 24 h recalls (88 % had two or more recalls). Procedures were repeated approximately 6 months after the initial visit among a subset of ninety-six participants.
Setting
Four centres (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA) across the USA.
Subjects
Men and women (n 477) aged 18–74 years.
Results
The geometric mean of total sugars was 167·5 (95 % CI 154·4, 181·7) g/d for the biomarker-predicted and 90·6 (95 % CI 87·6, 93·6) g/d for the self-reported total sugars intake. Self-reported total sugars intake was not correlated with biomarker-predicted sugars intake (r=−0·06, P=0·20, n 450). Among the reliability sample (n 90), the reproducibility coefficient was 0·59 for biomarker-predicted and 0·20 for self-reported total sugars intake.
Conclusions
Possible explanations for the lack of association between biomarker-predicted and self-reported sugars intake include measurement error in self-reported diet, high intra-individual variability in sugars intake, and/or urinary sucrose and fructose may not be a suitable proxy for total sugars intake in this study population.
Recent evidence suggests that Ca supplements increase the risk of cardiovascular events, but the mechanism(s) by which this occurs is uncertain. In a study primarily assessing the effects of various Ca supplements on blood Ca levels, we also investigated the effects of Ca supplements on blood pressure and their acute effects on blood coagulation. We randomised 100 post-menopausal women to 1 g/d of Ca or a placebo containing no Ca. Blood pressure was measured at baseline and every 2 h up to 8 h after their first dose and after 3 months of supplementation. Blood coagulation was measured by thromboelastography (TEG) in a subgroup of participants (n 40) up to 8 h only. Blood pressure declined over 8 h in both the groups, consistent with its normal diurnal rhythm. The reduction in systolic blood pressure was smaller in the Ca group compared with the control group by >5 mmHg between 2 and 6 h (P≤0·02), and the reduction in diastolic blood pressure was smaller at 2 h (between-groups difference 4·5 mmHg, P=0·004). Blood coagulability, assessed by TEG, increased from baseline over 8 h in the calcium citrate and control groups. At 4 h, the increase in the coagulation index was greater in the calcium citrate group compared with the control group (P=0·03), which appeared to be due to a greater reduction in the time to clot initiation. These data suggest that Ca supplements may acutely influence blood pressure and blood coagulation. Further investigation of this possibility is required.
Ca supplements, but not dietary Ca, have been associated with increased cardiovascular risk. This difference could be related to differences in their acute effects on serum Ca. We therefore examined the effects of Ca from different sources on serum Ca and phosphate in a randomised, cross-over trial of ten women (mean age of 69 years). Fasting participants received a single dose of 500 mg of Ca as citrate, citrate with a meal, fortified juice or a dairy product meal, with at least 6 d between each intervention. Blood was sampled before and 1, 2, 4 and 6 h after each intervention was ingested. Serum ionised and total Ca increased significantly from baseline over 6 h. Using calcium citrate fasting as a comparator, the elevations in ionised and total Ca were similar after fortified juice, delayed after calcium citrate with a meal and smaller after a dairy product meal. Serum phosphate and calcium–phosphate product increased from baseline after calcium citrate with a meal and after a dairy product meal, and they declined after calcium citrate fasting and after fortified juice. The elevations in serum Ca in the present study were only slightly different from those observed after the administration of 1000 mg of Ca in a previous study. These data indicate that different sources of Ca have different acute effects on serum Ca and support recommendations that dietary Ca might be safer than supplements. Whether these differences contribute to differences in cardiovascular risk requires further study.
Ca supplements are used for bone health; however, they have been associated with increased cardiovascular risk, which may relate to their acute effects on serum Ca concentrations. Microcrystalline hydroxyapatite (MCH) could affect serum Ca concentrations less than conventional Ca supplements, but its effects on bone turnover are unclear. In the present study, we compared the acute and 3-month effects of MCH with conventional Ca supplements on concentrations of serum Ca, phosphate, parathyroid hormone and bone turnover markers. We randomised 100 women (mean age 71 years) to 1 g/d of Ca as citrate or carbonate (citrate–carbonate), one of two MCH preparations, or a placebo. Blood was sampled for 8 h after the first dose, and after 3 months of daily supplementation. To determine whether the acute effects changed over time, eight participants assigned to the citrate dose repeated 8 h of blood sampling at 3 months. There were no differences between the citrate and carbonate groups, or between the two MCH groups, so their results were pooled. The citrate–carbonate dose increased ionised and total Ca concentrations for up to 8 h, and this was not diminished after 3 months. MCH increased ionised Ca concentrations less than the citrate–carbonate dose; however, it raised the concentrations of phosphate and the Ca–phosphate product. The citrate–carbonate and MCH doses produced comparable decreases in bone resorption (measured as serum C-telopeptide (CTX)) over 8 h and bone turnover (CTX and procollagen type-I N-terminal propeptide) at 3 months. These findings suggest that Ca preparations, in general, produce repeated sustained increases in serum Ca concentrations after ingestion of each dose and that Ca supplements with smaller effects on serum Ca concentrations may have equivalent efficacy in suppressing bone turnover.
Local structural and metabolic as well as inter-regional connectivity abnormalities have been implicated in the neuropathology of major depressive disorder (MDD). How local tissue properties affect intrinsic functional connectivity is, however, unclear. Using a cross-sectional, multi-modal imaging approach, we investigated the relationship between local cortical tissue abnormalities and intrinsic resting-state functional connectivity (RSFC) in MDD.
Method
A total of 20 MDD in-patients and 20 healthy controls underwent magnetic resonance imaging at 3 T for structural and functional imaging. Whole-brain cortical thickness was calculated and compared between groups. Regions with reduced cortical thickness defined seeds for subsequent whole-brain RSFC analyses. Contributions of structural tissue abnormalities on inter-regional RSFC were explicitly investigated.
Results
Lower cortical thickness was observed in MDD in the right dorsomedial prefrontal cortex (PFC), superior temporal gyrus/temporal pole, middle-posterior cingulate cortex, and dorsolateral PFC. No differences in local fractional amplitude of low-frequency fluctuations were observed. Lower thickness in patients' dorsomedial PFC further directly and selectively affected its RSFC with the precuneus, which was unaffected by symptom severity. No effects of cortical thickness in other regions showing abnormal thickness were observed to influence functional connectivity.
Conclusions
Abnormal cortical thickness in the dorsomedial PFC in MDD patients was observed to selectively and directly affect its intrinsic connectivity with the precuneus in MDD patients independent of depression severity, thereby marking a potential vulnerability for maladaptive mood regulation. Future studies should include an unmedicated sample and replicate findings using independent component analysis to test for morphometric effects on network integrity.
The scientific literature contains evidence suggesting that women who have been treated for breast cancer may, as a result of their diagnosis, increase their phyto-oestrogen (PE) intake. In the present paper, we describe the creation of a dietary analysis database (based on Dietplan6) for the determination of dietary intakes of specific PE (daidzein, genistein, glycitein, formononetin, biochanin A, coumestrol, matairesinol and secoisolariciresinol), in a group of women previously diagnosed and treated for postmenopausal breast cancer. The design of the database, data evaluation criteria, literature data entry for 551 foods and primary analysis by LC–MS/MS of an additional thirty-four foods for which there were no published data are described. The dietary intake of 316 women previously treated for postmenopausal breast cancer informed the identification of potential food and beverage sources of PE and the bespoke dietary analysis database was created to, ultimately, quantify their PE intake. In order that PE exposure could be comprehensively described, fifty-four of the 316 subjects completed a 24 h urine collection, and their urinary excretion results allowed for the description of exposure to include those identified as ‘equol producers’.
We summarize the status of a computer simulator for microlens planet surveys. The simulator generates synthetic light curves of microlensing events observed with specified networks of telescopes over specified periods of time. Particular attention is paid to models for sky brightness and seeing, calibrated by fitting to data from the OGLE survey and RoboNet observations in 2011. Time intervals during which events are observable are identified by accounting for positions of the Sun and the Moon, and other restrictions on telescope pointing. Simulated observations are then generated for an algorithm that adjusts target priorities in real time with the aim of maximizing planet detection zone area summed over all the available events. The exoplanet detection capability of observations was compared for several telescopes.
Lamesis Westw. Tijdschr. voor Entom. xxvi., p. 67. I would call attention to the possible identity of this genus and Xenorhipis Lec. The figure given by Westwood (pl. 3, fig. 8) certainly bears a very close resemblance to that published by me of Xenorhipis (Trans. Am. Ent. Soc. 1882, pl. iv., fig. 7, 8). If the two should prove identical, the name given by LeConte (Proc. Acad. 1866, p. 384) should have priority.