Plasma electron acceleration driven by a long-wave-infrared laser.

Laser-driven plasma accelerators provide tabletop sources of relativistic electron bunches and femtosecond x-ray pulses, but usually require petawatt-class solid-state-laser pulses of wavelength λL ~ 1 µm. Longer-λL lasers can potentially accelerate higher-quality bunches, since they require less power to drive larger wakes in less dense plasma. Here, we report on a self-injecting plasma accelerator driven by a long-wave-infrared laser: a chirped-pulse-amplified CO2 laser (λL ≈ 10 µm). Through optical scattering experiments, we observed wakes that 4-ps CO2 pulses with < 1/2 terawatt (TW) peak power drove in hydrogen plasma of electron density down to 4 × 1017 cm-3 (1/100 atmospheric density) via a self-modulation (SM) instability. Shorter, more powerful CO2 pulses drove wakes in plasma down to 3 × 1016 cm-3 that captured and accelerated plasma electrons to relativistic energy. Collimated quasi-monoenergetic features in the electron output marked the onset of a transition from SM to bubble-regime acceleration, portending future higher-quality accelerators driven by yet shorter, more powerful pulses.

Robotic-Assisted Surgery Training (RAST): Assessment of Surgeon Console Ergonomic Skills.

OBJECTIVE: The aim of this study was to evaluate the responsiveness of postgraduate year (PGY) general surgery residents (GSRs) to surgeon console ergonomics within the robotic-assisted surgery training (RAST) program. DESIGN: This was a prospective educational study. GSRs were prepared with a pretraining educational video. Faculty provided one-on-one resident hands-on training and testing. Nine proficiency criteria (emergency stop & recover; left side pod adjustments; touchpad controls; footswitch panel; energy control pedals; camera control & focus; arm swap; master & finger clutch; dual console settings control) were assessed with a 5-point Likert-scale. Responsiveness was defined as change in performance over time. The robotic platform was Da Vinci Xi (Intuitive Surgical, Sunnyvale, CA). The Dundee ready educational environment measure (DREEM) inventory was used by GSRs to assess the educational environment. SETTING: Tertiary care academic teaching institution. PARTICIPANTS: A total of 22 GSRs: 4 PGY 1, 4 PGY 2, 4 PGY 3, 5 PGY 4, 5 PGY 5. RESULTS: From June 2022 to March 2023 the hands-on console time decreased at testing when compared to baseline: median 39.0 (range 37-41) vs 20.1 (range 19-22) minutes, respectively. There was no difference in mean hands-on testing scores stratified by PGY: 4.85±0.4 PGY1; 4.98 ± 0.3 PGY2; 4.86 ± 0.4 PGY3, 4.88 ± 0.2 PGY4, and 4.91 ± 0.1 PGY5 (ANOVA test; p = 0.095). The overall DREEM score was 167.1 ± 16.9 with CAC = 0.908 (excellent internal consistency). CONCLUSIONS: Training in ergonomics on the surgeon console impacted the responsiveness of the GSRs with 51% console time reduction. There were no differences in hands-on testing scores among PGYs. Perception of the educational environment by the GSRs was high.

Rain triggers seasonal stratification in a temperate shelf sea.

The North Atlantic Storm Track acts as a conveyor belt for extratropical cyclones that frequently deliver high winds and rainfall to northwest European shelf seas. Storms are primarily considered detrimental to shelf sea stratification due to wind-driven mixing countering thermal buoyancy, but their impact on shelf scale stratification cycles remains poorly understood. Here, we show that storms trigger stratification through enhanced surface buoyancy from rainfall. A multidecadal model confirms that rainfall contributed to triggering seasonal stratification 88% of the time from 1982 to 2015. Stratification could be further modulated by large-scale climate oscillations, such as the Atlantic Multidecadal Variability (AMV), with stratification onset dates being twice as variable during a positive AMV phase than a negative one. Further insights into how changing storm activity will impact shelf seas are discussed beyond the current view of increasing wind-driven mixing, with significant implications for marine productivity and ecosystem function.

Identifying the social context of single- and mixed-species group formation in large African herbivores.

Despite continued interest in mixed-species groups, we still lack a unified understanding of how ecological and social processes work across scales to influence group formation. Recent work has revealed ecological correlates of mixed-species group formation, but the mechanisms by which concomitant social dynamics produce these patterns, if at all, is unknown. Here, we use camera trap data for six mammalian grazer species in Serengeti National Park. Building on previous work, we found that ecological variables, and especially forage quality, influenced the chances of species overlap over small spatio-temporal scales (i.e. on the scales of several metres and hours). Migratory species (gazelle, wildebeest and zebra) were more likely to have heterospecific partners available in sites with higher forage quality, but the opposite was true for resident species (buffalo, hartebeest and topi). These findings illuminate the circumstances under which mixed-species group formation is even possible. Next, we found that greater heterospecific availability was associated with an increased probability of mixed-species group formation in gazelle, hartebeest, wildebeest and zebra, but ecological variables did not further shape these patterns. Overall, our results are consistent with a model whereby ecological and social drivers of group formation are species-specific and operate on different spatio-temporal scales. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.

Accuracy of transvaginal ultrasound versus MRI in the PreOperative Diagnostics of low-grade Endometrial Cancer (PODEC) study: a prospective multicentre study.

AIM: To investigate if the diagnostic accuracy of transvaginal ultrasound (TVUS) performed by gynaecologists is sufficient for preoperative assessment of low-grade endometrial cancer (EC) compared to magnetic resonance imaging (MRI). MATERIALS AND METHODS: MRI and TVUS performed by gynaecologists were assessed at the participating centres. The MRI examinations were interpreted by two radiologists at the tertiary centre. Deep myometrial and cervical stroma invasion were visually assessed and compared to postoperative histopathology. RESULTS: Two hundred and fifty-nine patients were included. There was a statistically significant difference in specificity assessing deep myometrial invasion between MRI and TVUS (MRI 0.88, TVUS 0.68). There was no difference in sensitivity (MRI 0.73, TVUS 0.68). When assessing cervical stroma infiltration, MRI had a higher specificity (MRI 0.96, TVUS 0.90), but there was no difference in sensitivity (MRI 0.41, TVUS 0.32). CONCLUSION: MRI has higher specificity than TVUS performed by gynaecologists for assessing deep MI and CSI in low-grade EC, but similar sensitivities. The use of TVUS as a first-line test, rather than MRI, may be supported by this study in centres where access to MRI may be limited.

Histopathologic differences in granulomas of Mycobacterium bovis bacille Calmette Guérin (BCG) vaccinated and non-vaccinated cattle with bovine tuberculosis.

Mycobacterium bovis (M. bovis) is the zoonotic bacterium responsible for bovine tuberculosis. An attenuated form of M. bovis, Bacillus Calmette-Guerin (BCG), is a modified live vaccine known to provide variable protection in cattle and other species. Protection for this vaccine is defined as a reduction in disease severity rather than prevention of infection and is determined by evaluation of the characteristic lesion of tuberculosis: the granuloma. Despite its recognized ability to decrease disease severity, the mechanism by which BCG imparts protection remains poorly understood. Understanding the histopathologic differences between granulomas which form in BCG vaccinates compared to non-vaccinates may help identify how BCG imparts protection and lead to an improved vaccine. Utilizing special stains and image analysis software, we examined 88 lymph nodes obtained from BGC-vaccinated and non-vaccinated animals experimentally infected with M. bovis. We evaluated the number of granulomas, their size, severity (grade), density of multinucleated giant cells (MNGC), and the amounts of necrosis, mineralization, and fibrosis. BCG vaccinates had fewer granulomas overall and smaller high-grade granulomas with less necrosis than non-vaccinates. The relative numbers of high- and low- grade lesions were similar as were the amounts of mineralization and the density of MNGC. The amount of fibrosis was higher in low-grade granulomas from vaccinates compared to non-vaccinates. Collectively, these findings suggest that BCG vaccination reduces bacterial establishment, resulting in the formation of fewer granulomas. In granulomas that form, BCG has a protective effect by containing their size, reducing the relative amount of necrosis, and increasing fibrosis in low-grade lesions. Vaccination did not affect the amount of mineralization or density of MNGC.

Comparison of continuous versus intermittent enteral feeding in critically ill patients: a systematic review and meta-analysis.

BACKGROUND: The enteral route is commonly utilised to support the nutritional requirements of critically ill patients. However, there is paucity of data guiding clinicians regarding the appropriate method of delivering the prescribed dose. Continuous enteral feeding is commonly used; however, a bolus or intermittent method of administration may provide several advantages such as minimising interruptions. The purpose of this meta-analysis is to compare a continuous versus an intermittent or bolus enteral nutrition administration method. METHODS: A systematic review and meta-analysis were performed with studies identified from the PubMed, EMBASE, Cochrane Library and Web of Science databases. Studies were included if they compared a continuous with either an intermittent or bolus administration method of enteral nutrition in adult patients admitted to the intensive care unit. Study quality was assessed using the PEDro and Newcastle-Ottawa scoring systems. Review Manager was used for performing the random-effects meta-analysis on the outcomes of mortality, constipation, diarrhoea, increased gastric residuals, pneumonia, and bacterial colonisation. RESULTS: A total of 5546 articles were identified, and 133 were included for full text review. Fourteen were included in the final analysis. There was an increased risk of constipation with patients receiving continuous enteral nutrition (relative risk 2.24, 95% confidence interval 1.01-4.97, p = 0.05). No difference was identified in other outcome measures. No appreciable bias was identified. CONCLUSION: The current meta-analysis has not identified any clinically relevant difference in most outcome measures relevant to the care of critically ill patients. However, there is a paucity of high-quality randomised controlled clinical trials to guide this decision. Therefore, clinicians may consider either dosing regimen in the context of the patient's care requirements.

Relevance of prokaryotic subspecies in the age of genomics.

The availability of multiple gene sequences, and in particular full genome sequence data, for microbial strains has changed how taxonomists delineate subspecies belonging to the Archaea and Bacteria. Well-defined phylogenetic lineages that share higher genome similarity values compared to the widely used species thresholds are often described as subspecies, despite clear evidence of genetic isolation between them. These well-defined lineages, reflecting notable genetic isolation of the core genome represent more recently evolved, unique and sui generis evolutionary units. Because they bear all of the hallmarks of species, most contemporary subspecies likely represent species in their own right. Although there is considerable value in defining intraspecies variation (e.g., pathovar, serovar and symbiovar), the discriminating properties of such units are mostly encoded on accessory subgenomic compartments. We therefore argue that the taxonomic category of subspecies has become irrelevant and propose that its use should be discontinued. This will minimize inconsistencies related to the subjective nature of species-subspecies distinctions. Formal recognition of biologically relevant variation within species based on the accessory genome information will have practical significance in fields such as clinical, industrial and agricultural microbiology.

It is time for a new type of type to facilitate naming the microbial world.

Since January 1, 2001, the only acceptable nomenclatural type for species under the International Code of Nomenclature of Prokaryotes (ICNP) has been pure cultures. Here, we argue that this requirement is discordant with the more inclusive nature of nomenclatural types accepted under other codes of nomenclature and posit that the unique rigidity of the ICNP has failed to serve the broad research community and has stifled progress. This case is based on the axiom that many archaea and bacteria are interdependent in nature and therefore difficult, if not impossible, to grow, preserve, and distribute as pure cultures. As such, a large proportion of Earth's biodiversity cannot be named under the current system, which limits our ability to communicate about microbial diversity within and beyond the microbiology research community. Genome sequence data are now encouraged for valid publication of new taxa in microbial systematics journals, and metagenome-assembled genomes and single cell-amplified genomes are being generated rapidly from every biome on Earth. Thus, genome sequences are available for both cultivated and uncultivated microorganisms and can readily serve as a new category of nomenclatural type, allowing for a unified nomenclature for all archaea and bacteria, whether or not they are available as pure cultures. Ideally this would be under a single code of nomenclature but, as we review here, the newly established SeqCode will operate in parallel with the ICNP as a first step toward this goal.

Thoracic ultrasound for TB diagnosis in adults and children.

Thoracic ultrasound is an appealing alternative to chest radiography for the diagnosis of TB. Based on research experience conducting thoracic ultrasound for adults and children in South Africa, three key considerations for potential scale-up were identified. First, thoracic ultrasound requires a comprehensive training programme for novice users; artificial intelligence may be used to simplify training and interpretation. Second, a robust ultrasound device is needed with good subpleural resolution and a probe suitable for children. Third, comprehensive scanning of the lungs is time-intensive, and shorter scanning protocols may be more feasible in clinical practice.

L'échographie thoracique est une alternative attrayante à la radiographie pulmonaire pour le diagnostic de la TB. En prenant appui sur l'expérience acquise lors d'études ayant utilisé l'échographie thoracique chez l'adulte et l'enfant en Afrique du Sud, trois considérations clés pour une éventuelle utilisation accrue de cet outil ont été identifiées. Premièrement, tout nouvel utilisateur d'un échographe thoracique doit suivre un programme de formation exhaustif. L'intelligence artificielle pourrait être utilisée pour simplifier la formation et l'interprétation des résultats. Deuxièmement, un échographe de qualité est nécessaire, avec une bonne résolution sous-pleurale et une sonde adaptée à l'enfant. Troisièmement, une scannographie exhaustive des poumons est chronophage ; des protocoles de scannographie plus courts pourraient être plus faciles en pratique clinique.

Treatment outcomes and safety in children with rifampicin-resistant TB.

BACKGROUND: The treatment of rifampicin-resistant TB (RR-TB) in children is evolving rapidly. As newer regimens are introduced into routine care, it is vital to compare their outcome and safety with well-characterised clinical cohorts treated with historical regimens.METHODS: Study sample comprised a prospective observational cohort of children on routine RR-TB treatment, enrolled from 2011 to 2015 in Cape Town, South Africa. Children were followed for safety, treatment response and outcome.RESULTS: Of 136 children included, 27 (19.9%) were living with HIV and 48 (37.8%) had severe TB. The median time-to-culture conversion in children with bacteriological confirmation (n = 44) was 28.5 days (IQR 14.5-45). Overall, 118/129 (91.5%) had favourable TB treatment outcomes. Of 106 (77.9%) children who received an injectable drug, 9 (8.5%) developed hearing loss and 7/136 (5.1%) developed other Grade 3 or higher adverse events likely related to treatment.CONCLUSIONS: In this cohort with a substantial proportion of children with severe manifestations of TB and with HIV, TB treatment outcomes were excellent. Apart from hearing loss, few children developed severe adverse events related to treatment. This study provides robust reference data for future evaluation of shorter, injectable-sparing regimens.

Postmenopausal women's adherence to pelvic floor muscle exercises over 2 years.

OBJECTIVE: This study aimed to investigate women's adherence patterns to pelvic floor muscle exercises (PFME), their associated factors and within-pattern changes. METHODS: This was a secondary analysis using data collected from 647 women aged 55 years and older in the USA. Women were randomly assigned to either a 2-h class group or an equivalent content 20-min DVD group to receive PFME complemented with adherence enhancement strategies. Adherence was assessed at 3, 12 and 24 months using three self-reported items matching PFME parameters. The k-mean clustering and multinomial logistic regression were used to investigate adherence patterns and their associated factors, respectively. Descriptive statistics were used for within-pattern changes over time. RESULTS: Four adherence patterns, A, B, C and D, were identified. Women who displayed optimal adherence to all three aforementioned items, i.e. adherence pattern A, constituted 49.1%, 38.2% and 37.2% of women at 3, 12 and 24 months, respectively. Women with income > US$100,000 were more likely to display adherence pattern A within 12 months. Of women who had adherence pattern A at 3 months, 63.9% and 49.2% continued in this pattern at 12 and 24 months. CONCLUSIONS: Fewer than half of women displayed adherence pattern A for 2 years. Early optimal adherence predicted women's subsequent optimal adherence.

Salivary Testosterone and Sexual Function and Behavior in Men and Women: Findings from the Third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3).

Using data from the third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3) we examined associations between salivary testosterone (Sal-T) and sexual function and behavior. Single morning saliva samples were self-collected from a subsample of participants aged 18-74 years and analyzed using mass spectrometry. 1,599 men and 2,123 women were included in the analysis (40.6% of those invited to provide a sample). We adjusted for confounders in a stepwise manner: in model 1 we adjusted for age only; model 2 for age, season and relationship status, and model 3 we added BMI and self-reported health. In the fully adjusted models, among men, Sal-T was positively associated with both partnered sex (vaginal sex and concurrent partners) and masturbation. Among women, Sal-T was positively associated with masturbation, the only association with partnered sex was with ever experience of same-sex sex. We found no clear association between Sal-T and sexual function. Our study contributes toward addressing the sparsity of data outside the laboratory on the differences between men and women in the relationship between T and sexual function and behavior. To our knowledge, this is the first population study, among men and women, using a mass spectrometry Sal-T assay to do so.

Comparative cellular immune responses in calves after infection with Mycobacterium avium subsp. paratuberculosis, M. avium subsp. avium, M. kansasii and M. bovis.

In the present study, calves were infected with Mycobacterium avium subsp. paratuberculosis (MAP), Mycobacterium avium subsp. avium (M. avium), Mycobacterium kansasii (M. kansasii), or Mycobacterium bovis (M. bovis) to determine differences in cellular immunity. Comparative cellular responses were assessed upon stimulation of cells with mycobacterial whole cell sonicates respective of each infection group. Antigen-specific whole blood interferon gamma (IFN-γ) responses were observed in all infection groups compared to noninfected control calves, however, responses were more robust for M. bovis calves. Upon antigen stimulation of PBMCs, secretion of IFN-γ and IL-10 was higher for M. bovis calves compared to other infection groups. In contrast, IL-12 secretion was lower for M. bovis calves compared to MAP infected calves. Within the total PBMC population, higher numbers of CD4+, CD8+, and γδ TCR + T cells were observed for MAP and M. avium calves compared to M. bovis calves. This aligned with higher expression of CD26 on these subpopulations for MAP and M. avium calves, as well. In contrast, greater expression of CD25 was observed on CD4+ and γδ TCR + T cells and natural killer cells for M. bovis calves. Overall, similarities in cellular immune responses were observed between the closely related MAP and M. avium during infection of calves. In contrast, significant differences were noted between calves infected with MAP and M. bovis. This suggests that host immune responses to different mycobacteria may impact interpretation of diagnostic tools based upon their cellular immunity.

Human papillomavirus vaccine effectiveness within a cervical cancer screening programme: cohort study.

OBJECTIVE: To assess the effectiveness of an HPV vaccination programme in reducing the risk of cervical abnormalities identified at subsequent screening. DESIGN: Retrospective cohort study using administrative health data. SETTING: General population of Ferrara Province, Italy. POPULATION: Female residents born in 1986-1993 and participating in the organized cervical screening programme in 2011-2018, who were eligible for HPV vaccination in catch-up cohorts. METHODS: Logistic regression to evaluate the potential association between abnormal cervical cytology and one, two, three or at least one dose of HPV vaccine. MAIN OUTCOME MEASURES: Cervical abnormalities, as predicted by low-grade or high-grade cytology, by number of vaccine doses, stratified by age. RESULTS: The sample consisted of 7785 women (mean age 27.5 years, SD 2.3). Overall, 391 (5.0%) were vaccinated with ≥1 dose and 893 (11.5%) had abnormal cytology. Women receiving at least one vaccine dose were significantly less likely to have an abnormal cytology (adjusted odds ratio 0.52; 95% confidence interval 0.34-0.79). Similar results were observed for women receiving a single dose, for both bivalent and quadrivalent vaccines, and applying buffer periods (excluding cytological outcomes within 1 month, 6 months and 1 year of the first dose). CONCLUSIONS: In the context of an organised cervical screening programme in Italy, catch-up HPV vaccination almost halved the risk of cytological abnormalities. TWEETABLE ABSTRACT: Among Ferrara women, vaccination against human papillomavirus halved the risk of screening cervical abnormalities.

Efficacy of a dietitian-led very low calorie diet (VLCD) based model of care to facilitate weight loss for obese patients prior to elective, non-bariatric surgery.

BACKGROUND: Elective surgery in obese adults carries a higher risk of post-operative infection and prolonged hospital stays, and surgeons may postpone surgery for patients with obesity until they lose weight. The present study aimed to determine the efficacy of a dietitian-led very low calorie diet (VLCD)-based model of care with respect to achieving weight loss for obese patients prior to surgery. METHODS: This mixed-methods study included a medical chart audit of patients referred to a VLCD-based model over 23 months, as well as a survey of recently treated patients and surgeons who utilised the model. Preoperative weight loss targets were set by surgeons, and the dietitian prescribed individualised VLCD-based treatment. Efficacy was determined as weight loss considered sufficient for surgery, clinical safety of VLCD-based treatment, feasibility, and stakeholder value. Pre/post-intervention differences in clinical measures were explored by paired t-test or Wilcoxon tests as appropriate. RESULTS: Data on seventy-eight eligible patients [mean (SD) 45 (13) years, 90% female, body mass index 44.3 (6.2) kg m-2 ] demonstrated significant mean (SD) weight loss of 7.4% (5.3%) body weight (P < 0.05). Most patients (70%, n = 50/71) achieved sufficient weight loss to proceed to surgery. Fifty-six per cent of patients reported mild side effects (n = 43/77) and none led to treatment cessation. Surgeons reported VLCD-based treatment made operations easier (83%, n = 10/12) and shorter (75%, n = 9/12) and all recommended the model of care. All surveyed patients (n = 24) reported satisfaction with their VLCD-based model experience. CONCLUSIONS: A dietitian-led VLCD-based model achieved sufficient weight loss to facilitate elective surgery for most patients. The approach was feasible, highly valued by patients and surgeons, and resulted in perceived surgical benefits.