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Summary: A novel methodology is presented for reconstructing the Eulerian number density field of dispersed gas‐droplet flows modelled using the fully Lagrangian approach (FLA). In this work, the nonparametric framework of kernel regression is used to accumulate the FLA number density contributions of individual droplets in accordance with the spatial structure of the dispersed phase. The high variation which is observed in the droplet number density field for unsteady flows is accounted for by using the Eulerian‐Lagrangian transformation tensor, which is central to the FLA, to specify the size and shape of the kernel associated with each droplet. This procedure enables a high level of structural detail to be retained, and it is demonstrated that far fewer droplets have to be tracked in order to reconstruct a faithful Eulerian representation of the dispersed phase. Furthermore, the kernel regression procedure is easily extended to higher dimensions, and inclusion of the droplet radius within the phase space description using the generalised fully Lagrangian approach (gFLA) additionally enables statistics of the droplet size distribution to be determined for polydisperse flows. The developed methodology is applied to a range of one‐dimensional and two‐dimensional steady‐state and transient flows, for both monodisperse and polydisperse droplets, and it is shown that kernel regression performs well across this variety of cases. A comparison is made against conventional direct trajectory methods to determine the saving in computational expense which can be gained, and it is found that 103$$ 1{0}^3 $$ times fewer droplet realisations are needed to reconstruct a qualitatively similar representation of the number density field. [ABSTRACT FROM AUTHOR]

Background: Gulf War Illness (GWI) is a chronic, multi‐symptom disorder affecting 25%–32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut‐brain axis, we explore the relationship between post‐traumatic stress disorder (PTSD), GWI, and self‐reported GI disorders among GW veterans. Methods: Veterans from the Gulf War Era Cohort and Biorepository responded to a mail‐based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI−, GWI+/PTSD−, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI). Key Results: The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD− group (aORIBS = 3.12, 95% CI: 1.93–5.05; aORGERD = 2.04, 95% CI: 1.44–2.90; aORCP = 1.85, 95% CI: 1.23–2.80), which had a higher odds of these disorders than the GWI− group (aORIBS = 4.38, 95% CI: 1.55–12.36; aORGERD = 2.51 95% CI: 1.63–3.87; aORCP = 2.57, 95% CI: 1.53–4.32). Conclusions & Inferences: GW veterans with GWI and PTSD have significantly higher odds of specific self‐reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease. [ABSTRACT FROM AUTHOR]

Abstract: Aim: An airtight anastomosis on intra‐operative leak testing has been previously demonstrated to be associated with a lower risk of clinically significant postoperative anastomotic leak following left‐sided colorectal anastomosis. However, to date, there is no consistently agreed upon method for management of an intra‐operative anastomotic leak. Therefore, we powered a noninferiority study to determine whether suture repair alone was an appropriate strategy for the management of an intra‐operative air leak. Method: This is a retrospective cohort analysis of prospectively collected data from a tertiary care referral centre. We included all consecutive patients with left‐sided colorectal or ileorectal anastomoses and evidence of air leak during intra‐operative leak testing. Patients were excluded if proximal diversion was planned preoperatively, a pre‐existing proximal diversion was present at the time of surgery or an anastomosis was ultimately unable to be completed. The primary outcome measure was clinically significant anastomotic leak, as defined by the Surgical Infection Study Group at 30 days. Results: From a sample of 2360 patients, 119 had an intra‐operative air leak during leak testing. Sixty‐eight patients underwent suture repair alone and 51 underwent proximal diversion or anastomotic reconstruction. The clinically significant leak rate was 9% (6/68; 95% CI: 2–15%) in the suture repair alone arm and 0% (0/51) in the diversion or reconstruction arm. Conclusion: Suture repair alone does not meet the criteria for noninferiority for the management of intra‐operative air leak during left‐sided colorectal anastomosis. Further repair of intra‐operative air leak by suture repair alone should be reconsidered given these findings. [ABSTRACT FROM AUTHOR]

Purpose The current study aimed to evaluate environmental effects of neurocognitive baseline performance and overall symptom reports among student-athletes who took the ImPACT baseline assessment in a clinical setting or their home environment. Methods Participants were selected from an archival de-identified database. The sample consisted of 1,893 (37.3% male and 62.7% female) student-athletes with a mean age of 19.71 years. All student-athletes were administered ImPACT as a neurocognitive baseline screener prior to the beginning of their respective sport. Student-athletes were further divided into two groups: 1. At-home (n=405), and 2. In-clinic (n=405). Multiple independent samples t-tests were utilized to compare mean composite scores between the two groups. Results The independent samples t-test yielded a significant difference between groups on the ImPACT reaction time composite score, t(1891)=3.81, p<.001, and total symptom score, t(1891)=1.74, p=.024. Student-athletes who completed ImPACT at home demonstrated a significantly higher (slower) reaction time while also reporting significantly fewer symptoms. Conclusions When COVID-19 shut down our once-perceived "normal" societal function, university athletics were forced to change how they conducted concussion baseline screening for their student-athletes. The findings of the present study suggest the need for careful consideration regarding the environment of such neurocognitive baseline assessments as some factors including reaction time and total symptom report may be influenced by the test setting. Future studies should further explore possible confounding variables related to concussion assessment, such as test environment, that may be a unique precipitating factor of the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Hunting in the neotropics is a widespread form of resource extraction. However, there is increasing concern that current activities are leading to the decline and extirpation of vulnerable species; particulary ateline primates, large ungulates (such as tapirs and white-lipped peccaries) and large birds such as curassows. Hunting patterns are expected to be a product of two principal influences: the value of return for a given amount of effort invested into hunting, and cultural factors that determine the prestige and usefulness of prey. Previous work has suggested that hunting profiles change in a predictable way over time, becoming more diverse and more dependent on smaller bodied species as preferred, large-bodied prey become scarcer. In this paper, we evaluate the hunting profiles of 78 neotropical communities in Central and South America. We investigate the uniformity of species preferences, whether communities that are geographically closer have similar hunting profiles, and whether the age and size of settlements can be used to predict the type and diversity of species targeted. We found that there was only a weak correlation between the structure of communities' hunting profiles and their geographical proximity. Neither a community's size nor age was a good predictor of the shape and structure of its hunting profile. Our data suggest that either the availability of prey or the cultural influences dictating the value of different species can change rapidly over small distances, and that older and larger settlements do not impact prey species distributions in a predictable way. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) infection is known to increase in-hospital mortality, but little is known about its association with long-term health. Two hundred and thirty-seven deaths occurred among 707 patients with MRSA infection at the time of hospitalization and/or nasal colonization followed for almost 4 years after discharge from the Atlanta Veterans Affairs Medical Center, USA. The crude mortality rate in patients with an infection and colonization (23·57/100 person-years) was significantly higher than the rate in patients with only colonization (15·67/100 person-years, P = 0·037). MRSA infection, hospitalization within past 6 months, and histories of cancer or haemodialysis were independent risk factors. Adjusted mortality rates in patients with infection were almost twice as high compared to patients who were only colonized: patients infected and colonized [hazard ratio (HR) 1·93, 95% confidence interval (CI) 1·31–2·84]; patients infected but not colonized (HR 1·96, 95% CI 1·22–3·17). Surviving MRSA infection adversely affects long-term mortality, underscoring the importance of infection control in healthcare settings. [ABSTRACT FROM AUTHOR]

Beet leafhopper, Circulifer tenellus (Baker) (Homoptera: Cicadellidae), is the only known North American vector of beet curly top virus (Geminiviridae), which causes major economic losses in a number of crops including sugar beet, tomato, beans, and peppers. Beet curly top virus is a phloem-limited, persistently transmitted, circulative geminivirus. The strain/species of curly top virus used in this study is the CFH strain, also referred to as beet severe curly top virus (BSCTV). The direct current (DC) electrical penetration graph technique was used to determine the specific stylet penetration behavior associated with inoculation of BSCTV. Viruliferous leafhoppers were allowed to feed on healthy 3–4-week-old sugar beet plants until specific electrical penetration graph waveforms were produced, at which point feeding was artificially terminated. A series of comparisons between leafhoppers that produced different combinations of waveforms clearly implicated waveform D1 as the only waveform correlated with inoculation of BSCTV. All successful inoculations contained waveform D1, and 56 out of 64 leafhoppers that produced waveform D1 successfully inoculated test plants. Eighty-five leafhoppers did not produce waveform D1 and none of these inoculated BSCTV. While the occurrence of waveform D1 appears to be necessary for BSCTV inoculation, there was no correlation between duration of waveform D1 and inoculation success rate. The correlation of waveform D1 and BSCTV inoculation found in this study implies that waveform D1 is associated with phloem salivation. [ABSTRACT FROM AUTHOR]

Feeding behavior of beet leafhopper, Circulifer tenellus (Baker) (Homoptera: Cicadellidae), was studied with a DC electrical penetration graph. Nine different electrical penetration graph waveforms associated with feeding were identified and characterized. Waveforms were correlated with specific feeding behaviors using a number of techniques, including high magnification video recording, honeydew analysis, stylectomy, and histological processing. Waveforms were grouped into three phases based on feeding behavior: pathway phase (waveforms A, B1, B2, and C), non-phloem ingestion phase (waveform G), and phloem phase (waveforms D1, D2, D3, and D4). No ingestion was found to occur during waveforms A, B1, B2, and C. Waveform G was associated primarily with ingestion of xylem sap and occasionally with ingestion of mesophyll sap. Stylet tips were located in phloem during waveforms D1, D2, and D3, and waveforms D2 and D3 were correlated with ingestion of phloem sap. Waveform D4 probably also plays a role in phloem ingestion, because D4 is very brief and always occurs embedded in either waveform D2 or D3. In contrast to most other homopteran insects, rate of honeydew production (and hence rate of ingestion) was much lower on phloem than on xylem. More rapid rates of ingestion are expected on phloem, because its high turgor pressure drives sap into the feeding insect whereas the negative pressure of xylem sap is expected to cause a slow rate of ingestion. The very slow ingestion rate of beet leafhopper feeding on phloem suggests that it is not able to exploit the high turgor pressure of phloem to achieve the high rate of ingestion that is typical of phloem ingestion by other insects. [ABSTRACT FROM AUTHOR]

This article presents a brief review of the nanoscale free-electron model, which provides a continuum description of metal nanostructures. It is argued that surface and quantum-size effects are the two dominant factors in the energetics of metal nanowires, and that much of the phenomenology of nanowire stability and structural dynamics can be understood based on the interplay of these two competing factors. A linear stability analysis reveals that metal nanocylinders with certain magic conductance values G=1,3,6,12,17,23,34,42,51,67,78,96,... times the conductance quantum are exceptionally stable. A nonlinear dynamical simulation of nanowire structural evolution reveals a universal equilibrium shape consisting of a magic cylinder suspended between unduloidal contacts. The lifetimes of these metastable structures are also computed. [ABSTRACT FROM AUTHOR]

The history and importance of superdeformation in nuclei is briefly discussed. A simple two-level model is then employed to obtain an elegant expression for the branching ratio for the decay via the E1 process in the normal-deformed band of superdeformed nuclei. From this expression, the spreading width Γ↓ for superdeformed decay is found to be determined completely by experimentally known quantities. The accuracy of the two-level approximation is verified by considering the effects of other normal-deformed states. Furthermore, by using a statistical model of the energy levels in the normal-deformed well, we can obtain a probabilistic expression for the tunneling matrix element V. [ABSTRACT FROM AUTHOR]

We study the influence of a magnetic impurity or ultrasmallquantum dot on the charge persistent current of a mesoscopicring. The system consists of electrons in a one-dimensionalring threaded by spin-dependent Aharonov–Bohm/Casher fluxes,coupled via an antiferromagnetic exchange interaction to alocalized electron. By passing to a basis of electron stateswith definite parities, the problem is mapped onto a Kondomodel for the even-parity channel plus free electrons in theodd-parity channel. The twisted boundary conditionsrepresenting the fluxes couple states of opposite parityunless the twist angles satisfy φα=fαπ,where fα are integers, with spin indexα=↑, ↓. For these special values ofφα, the model is solved exactly by a Bethe ansatz.Special cases are investigated in detail. In particular weshow that the charge stiffness in the caseφ↑=φ↓ is insensitive to the presenceof the magnetic impurity/quantum dot. [ABSTRACT FROM AUTHOR]

In this paper we survey the development of the use of quantitative methods in American archaeology, using for our guidance the contents of American Antiquity since its first publication in 1935. We conclude that the utility of ‘Confirmatory Data Analysis’ has been much overrated in archaeology, and suggest that the alternative technique of ‘Exploratory Data Analysis’, developed by Tukey and others, may be greatly preferable. [ABSTRACT FROM PUBLISHER]

Residues of the DDT group, particularly p,p′-DDT (DDT) were detected in high or unusual amounts in some wildlife samples collected in fruit orchards near Wenatchee, Washington from 1979 to 1983. Samples of birds contained p,p′-DDE (DDE) and DDT in ratios (DDE:DDT) as low as 2.6:1 in eggs and 1.9:1 in brains. An unexpectedly high number (about 50%) of some samples, such as fat of adult waterfowl, contained unusually low DDE:DDT ratios (≤10:l). At the lower sensitivity level (0.01 μg/g), 96% of the samples contained DDE and 46% contained DDT. From about 1946 to 1970, technical DDT was applied at very high rates to orchards in Washington (56 to 73 kg/ha/yr); some areas probably received 5≥1000 kg/ha over this period. Considerable wildlife mortality from DDT was documented during the period of intensive use, but only one DDT-related mortality was recorded during this study. The possible origin of the residues is discussed. Occurrence of DDT and its metabolites in resident wildlife and its food indicates continuing contamination that probably originates largely from past legal applications in the orchard system. [ABSTRACT FROM AUTHOR]

Summary. In crushed goldfish optic nerve, regenerating axons cross the site of lesion within 10 days following injury. Some 30 days later, Schwann cells accumulate at the lesion, where they myelinate the new axons. In this study, we have used immunohistochemistry and electron microscopy to examine the cellular environment of the crush site prior to the establishment of Schwann cells in order to learn more about the early events that contribute to axonal regeneration. During the first week following injury, macrophages enter the site of lesion and efficiently phagocytose the debris. The infiltration of macrophages precedes the arrival of regenerating axons that abut and surround these phagocytes. Based on EM morphology and phagocytic capacity, macrophages of the type observed at the site of lesion are not present in the degenerating distal nerve segment, where debris clearance is shared between conventional microglia and astrocytes over a period of several weeks. During this period, axon bundles emerging distally from the injury zone become enwrapped by astrocyte processes, thereby re-establishing the characteristic fascicular cytoarchitecture of the optic nerve. The process of fasciculation also leads to the displacement of myelin debris to the margins of the fiber bundles, where it is trapped by the astrocytes. Our results suggest that the early robust appearance of macrophages at the lesion, and their effectiveness as phagocytes compared with the microglia distally, may contribute to the vigorous axonal regeneration across the crush, beyond which axons<197>excepting the pioneers<197>extend through newly formed debris-free channels delineated by astrocyte processes. [ABSTRACT FROM AUTHOR]

The perception of exertion is a complex phenomenon in which local muscular and joint factors, as well as central cardio-respiratory factors are thought to play important roles. This study examined the effects of backpack load carriage on ratings of perceived exertion (RPE). Ten well conditioned young men carried 0,20 and 40% of body mass in an external frame backpack at two speeds normalized for stature (0·75 and 0·95 statures per second). Steady-state ventilation, cardiorespiratory and RPE data were collected during the last 5 minutes of each of six randomly administered 10-minute walks on a motorised treadmill. With the exception of breathing frequency (which did not change), ventilatory, cardiorespiratory and RPE responses increased linearly with increases in load carried and relative speed. Correlations calculated between RPE and cardio-respiratory measures indicated a reasonably high degree of relationship ([Vdot]O2, r = 0·75; HR, r = 0·47; [Vdot]I, r = 0·58). However, when the increment in RPE over its maximum range was compared to the relative change in heart rate and oxygen consumption, it was observed that as soon as added load was carried the perception of exertion increased almost twice as much as did the cardio-respiratory measures when compared with the non-loaded walks. This may lend support to the contention that ‘local’ factors, if accentuated by load carriage, can dominate the overall perception of exertion. [ABSTRACT FROM PUBLISHER]

The mass spectral fragmentation reactions of twenty-one 1,1-dichlorocyclopropanes prepared from various isomeric octenes are discussed. The most characteristic reaction may be represented as follows: [ABSTRACT FROM AUTHOR]

Plasma cholesterol concentrations were reduced in 3 human volunteers during ingestion of diets containing alfalfa seeds (AS) for 3 weeks. No signs of toxicity were detected through serum determinations of multiple parameters. The ingestion of AS in rats decreased the concentration of plasma cholesterol, reduced intestinal absorption of exogenous and endogenous cholesterol, and increased fecal biliary excretion. [ABSTRACT FROM AUTHOR]

The author highlights the global burden of unintentional and intentional injury. A discussion of the distinction of injuries from accidents is provided. The author emphasizes the role of sports medicine and related allied health practitioners in greater public health injury prevention. The author relates the things that health professionals must know and do regarding the injury burden.

The article comments on the paper titled "Nonlinear current-voltage curves of gold quantum point contacts," by M. Yoshida and colleagues. The authors object to some of the conclusions and assumptions made in the study. They have provided evidence that, contrary to the study results, nanowires do not behave as classical elastic solids.