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1.
Phys Rev Lett ; 132(15): 155101, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682996

RESUMO

The sheared-flow-stabilized Z pinch concept has been studied extensively and is able to produce fusion-relevant plasma parameters along with neutron production over several microseconds. We present here elevated electron temperature results spatially and temporally coincident with the plasma neutron source. An optical Thomson scattering apparatus designed for the FuZE device measures temperatures in the range of 1-3 keV on the axis of the device, 20 cm downstream of the nose cone. The 17-fiber system measures the radial profiles of the electron temperature. Scanning the laser time with respect to the neutron pulse time over a series of discharges allows the reconstruction of the T_{e} temporal response, confirming that the electron temperature peaks simultaneously with the neutron output, as well as the pinch current and inductive voltage generated within the plasma. Comparison to spectroscopic ion temperature measurements suggests a plasma in thermal equilibrium. The elevated T_{e} confirms the presence of a plasma assembled on axis, and indicates limited radiative losses, demonstrating a basis for scaling this device toward net gain fusion conditions.

3.
Am Nat ; 202(2): E31-E52, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37531273

RESUMO

AbstractEcological and evolutionary processes underlying spatial variation in signals involved in mate recognition and reproductive isolation are crucial to understanding the causes of population divergence and speciation. Here, to test hypotheses concerning the causes of song divergence, we examine how songs of two sister species of Atlantic Forest suboscine birds with innate songs, the Pyriglena fire-eye antbirds, vary across their ranges. Specifically, we evaluated the influence of isolation by distance and introgressive hybridization, as well as morphological and environmental variation, on geographic variation in male songs. Analyses based on 496 male vocalizations from 63 locations across a 2,200-km latitudinal transect revealed clinal changes in the structure of songs and showed that introgressive hybridization increases both the variability and the homogenization of songs in the contact zone between the two species. We also found that isolation by distance, morphological constraints, the environment, and genetic introgression independently predicted song variation across geographic space. Our study shows the importance of an integrative approach that investigates the roles of distinct ecological and evolutionary processes that influence acoustic signal evolution.


Assuntos
Evolução Biológica , Passeriformes , Animais , Masculino , Vocalização Animal , Passeriformes/genética , Isolamento Reprodutivo
4.
Am Surg ; 89(5): 2150-2153, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35232246

RESUMO

The origins of wound care date back to ancient civilizations. From boiling oil to honey to wine, healers and caregivers have adopted a fascinating array of items to cleanse, dress, and bandage wounds over the ages. While wound care practices have developed over time, the physicians and surgeons of ancient times and the Middle Ages helped build the foundation for present-day wound care. A modern scientific understanding of these treatments illustrates why practitioners abandoned some practices while others remain in use today.


Assuntos
Mel , Cirurgiões , Vinho , Pessoa de Meia-Idade , Humanos , Cicatrização , Bandagens
5.
Rev Sci Instrum ; 93(10): 103535, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319390

RESUMO

Two newly developed, eight-channel, integrated Beam Emission Spectroscopy (BES) detectors have been installed at Huan-Liuqi-2A tokamak, which extends the existing 16 single-channel modular BES system with additional 16 spatial channels. The BES collects the Doppler-shifted Balmer Dα emission with a spatial resolution of 1 cm (radial) × 1.5 cm (poloidal) and a temporal resolution of 0.5 µs to measure long-wavelength (k⊥ρi < 1) density fluctuations. Compared to the modular BES, the dark noise of the integrated BES is reduced by 50%-60% on average. The signal-to-noise ratio of the integrated BES system is optimized by the high light throughput front-end optics, high quantum efficiency photodiodes, high-gain, low-noise preamplifiers, and sufficient cooling capacity provided by the thermoelectric cooling (TEC) units that maintain the detectors at -20 °C. Crosstalk between channels that share the same optical system is found to be negligible. High-quality density fluctuation data enables 2D (radial-poloidal) imaging of turbulence, which allows for multi-channel spectral analysis, multi-channel cross-correlation analysis and velocimetry analysis. Preliminary results show that BES successfully captures the spatiotemporal features of the local turbulence and obtains statistically consistent turbulence characterization results.

6.
Plast Surg (Oakv) ; 30(2): 130-135, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35572081

RESUMO

Objective: In digital nerve defects that require grafting, autografts remain the efficacious option. The sensory posterior interosseous nerve (PIN) is an ideal choice as it is of similar caliber to digital nerves and leaves no donor morbidity upon resection. However, a finite length of harvestable PIN exists, and considerable variations of this length have been reported in the literature. There exists no predictive model to estimate this length. We sought to determine a method to accurately predict the available length of PIN based on individual patient anthropometry. Methods: A cadaveric dissection study was performed in a fresh tissue laboratory. The length of the sensory branch of the PIN and various anthropometric measurements were made in respect to surface anatomy of the ulna to develop a predictable ratio for available PIN donor graft. Results: A total of 16 specimens were obtained. On average the length of the PIN was 5.7 cm (range: 3.3-9. cm) and the length of the ulna was 25.7 cm (range: 23.5-30.6 cm). The ratio of PIN to ulnar length was 0.222 (r = 0.4651). Using one-fifth the length of the ulna, the mean predicted length of the PIN was 5.14 cm (range: 4.7-6.1 cm). On univariate analysis, there was no significant difference between the measured and predicted PIN length (P = .249). Conclusion: An anthropometric ratio predicated on reproducible surface anatomy of the ulna is a useful tool in predicting the sensory PIN length. Such a prediction may be a useful in guiding patient discussions concerning surgical options for digital nerve reconstruction.


Objectif: Dans les cas d'anomalies des nerfs digitaux qui exigent une greffe, les autogreffes sont les plus efficaces. Le nerf interosseux postérieur (NIP) sensitif est le choix idéal, car son calibre est semblable à celui des nerfs digitaux et qu'il ne provoque aucun problème de santé au site de résection. Cependant, la longueur du NIP pouvant être récolté est limitée, et d'énormes variations sont présentées dans les publications. Aucun modèle prédictif ne permet d'évaluer cette longueur. Les chercheurs ont entrepris d'établir une méthode pour prédire avec fiabilité la longueur disponible du NIP d'après les caractéristiques anthropométriques de chaque patient. Méthodologie: Les chercheurs ont procédé à une étude de dissection cadavérique dans un laboratoire de tissus frais. Ils ont mesuré le rameau sensitif du NIP et diverses dimensions anthropométriques d'après l'anatomie de surface de l'ulna pour établir un ratio prévisible de greffe du NIP disponible chez le donneur. Résultats: Les chercheurs ont obtenu 16 prélèvements et calculé une longueur moyenne du NIP de 5,7 cm (plage de 3,3 cm à 9,6 cm) et une longueur moyenne de l'ulna de 25,7 cm (plage de 23,5 cm à 30,6 cm). Ils ont calculé un ratio de 0,222 (r = 0,4651) entre la longueur du NIP et de l'ulna. D'après le cinquième de la longueur de l'ulna, ils ont prédit une longueur moyenne du NIP de 5,14 cm (plage de 4,7 cm à 6,1 cm). À l'analyse univariée, ils n'ont constaté aucune différence significative entre la longueur mesurée et prédite du NIP (P = 0,249). Conclusion: Le ratio anthropométrique établi d'après l'anatomie de la surface reproductive de l'ulna est un outil utile pour prédire la longueur du NIP sensitif. Une telle prédiction peut être utile pour orienter les échanges avec le patient au sujet des possibilités chirurgicales de la reconstruction du nerf digital.

7.
Epidemiol Infect ; 151: e44, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35499070

RESUMO

Contact with livestock and consumption of unpasteurised dairy products are associated with an increased risk of zoonotic and foodborne infection, particularly among populations with close animal contact, including pastoralists and semi-pastoralists. However, there are limited data on disease risk factors among pastoralists and other populations where livestock herding, particularly of dromedary camels, is common. This cross-sectional study used a previously validated survey instrument to identify risk factors for self-reported symptoms. Adults (n = 304) were randomly selected from households (n = 171) in the Somali Region of Ethiopia, a region characterised by chronic food insecurity, population displacement, recurrent droughts and large semi-pastoralist and pastoralist populations. Multivariable logistic regression assessed associations between self-reported symptoms and type of milk consumed, controlling for demographics and human-animal interaction. Consumption of days-old unrefrigerated raw camel milk was significantly associated with symptoms in the 30 days prior to the survey (AOR = 5.07; 95% CI 2.41-10.66), after controlling for age, refugee status, sanitation, camel ownership and source of drinking water and accounting for clustering. Consumption of days-old unrefrigerated raw ruminant milk was significantly associated with symptoms (AOR = 4.00, 95% CI 1.27-12.58). Source of drinking water and camel ownership, a proxy for camel contact, were significantly associated with the outcome in each model. There were no significant associations between self-reported symptoms and fresh or soured animal milk consumption. Research is needed to identify pathogens and major routes of transmission. Tailored communication campaigns to encourage safe food preparation should also be considered.


Assuntos
Água Potável , Leite , Adulto , Animais , Humanos , Autorrelato , Camelus , Gado , Etiópia/epidemiologia , Estudos Transversais , Propriedade , Somália , Febre
9.
J Plast Surg Hand Surg ; 55(1): 17-20, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33043751

RESUMO

Proper injection of the posterior interosseous nerve (PIN) is important for both the therapeutic and diagnostic management of wrist pain. However, no anatomical study exists describing the site of injection based on individual wrist width. We sought to develop a reproducible anthropometric ratio utilizing external wrist surface anatomy to predict a safe and accurate injection site for the PIN. Fresh frozen cadaver forearms were dissected at the University of Louisville tissue lab. Several anthropometric measurements were obtained in order to develop a reproducible ratio to calculate location of injection. A total of 16 cadaver forearms of equal male to female ratio were obtained. On average, the male forearm had a greater mean wrist circumference obtained at the level of Lister's tubercle compared to female forearms, 17.1 cm vs. 13.5 cm. An injection given ulnar to proximal edge of Lister's tubercle at a length of one-fourth the distance between Lister's tubercle and radial aspect of ulnar styloid resulted in 100% accurate perineural injection without intraneural injection. An anthropometric ratio of one-fourth the distance from Lister's tubercle to the ulnar styloid was able to predict accurate injection sites for the distal PIN in cadaveric specimens of varying anatomical proportions.


Assuntos
Injeções/métodos , Bloqueio Nervoso/métodos , Nervo Radial/anatomia & histologia , Punho/anatomia & histologia , Pontos de Referência Anatômicos , Cadáver , Feminino , Humanos , Masculino
10.
Eplasty ; 20: e12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33214803

RESUMO

Introduction: Use of local anesthesia in awake patients undergoing hand surgery has become increasingly popular. A thorough understanding of local anatomy, such as the distal wrist for ulnar nerve block, is required to provide safe blockade. We sought to conduct an anatomic study of the distal wrist and review cadaveric studies describing various techniques for ulnar nerve block. Methods: Dissection of fresh-frozen cadaver forearms at the University of Louisville Robert Acland Fresh Tissue Lab assessing relationships between the flexor carpi ulnaris tendon and the ulnar nerve and the ulnar artery was performed. Three cadaveric studies on ulnar nerve blockade using the ulnar, volar, and/or transtendinous technique were identified and reviewed. Results: A total of 16 cadaver forearms of equal male to female ratio were obtained. The ulnar nerve was noted to be directly posterior to the flexor carpi ulnaris tendon in 15 (93.8%) forearms, with 1 (6.3%) specimen having the nerve extend along the ulnar border of the flexor carpi ulnaris. The ulnar artery was radial to the ulnar nerve 1 cm proximal to the pisiform in all specimens. In all 3 cadaveric studies, only the ulnar technique was associated with no ulnar artery and/or ulnar nerve injury. Conclusion: Knowledge of distal wrist anatomy can help minimize risk of iatrogenic injury during local blockade. On review, the ulnar approach provides the safest method for ulnar nerve block.

11.
Zootaxa ; 4817(1): zootaxa.4817.1.1, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-33055681

RESUMO

Populations in the Rufous Antpitta (Grallaria rufula) complex occupy humid montane forests of the Andes from northern Colombia and adjacent Venezuela to central Bolivia. Their tawny to cinnamon-colored plumages are generally uniform, featuring subtle variation in hue and saturation across this range. In contrast to their conservative plumage, substantial vocal differences occur among geographically isolated or parapatric populations. Working within the framework of a comprehensive molecular phylogeny, we reexamined species limits in the G. rufula complex, basing taxonomic recommendations on diagnostic differences in vocalizations and considering identifiable differences in plumage where pertinent. We identified 16 populations for species designation, including seven populations previously described as subspecies and, remarkably, six new species described herein. Within one of these species, we identified less robust vocal differences between populations that we designate as subspecies. Geographic variation exists within another species, but its critical evaluation requires additional material. Taxonomic revisions of groups consisting of cryptic species, like the Grallaria rufula complex, are imperative for their conservation. Rather than widespread species as currently defined, these complexes can comprise many range-restricted taxa at higher risk of extinction given the continuing human pressures on their habitats.


Assuntos
Passeriformes , Animais , Filogenia
12.
Ann Med Surg (Lond) ; 56: 43-47, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32577230

RESUMO

BACKGROUND: Surgical skills training is a recognized vital component of medical education, yet a standardized curriculum does not exist. Early opportunities for skills development and mentorship may increase student interest in pursuing surgery. We evaluated the effects of a student-led, faculty-supervised suture clinic on student comfort level with basic surgical skills and interest in surgery. METHODS: A cohort survey study of 103 second-year medical students participating in a surgical skills course was performed between the years 2016-2018. Upon completion of the course, we assessed their comfort level with performing six basic skills as well as their interest in pursuing surgery based on pre- and post-course surveys. RESULTS: Mean age was 25 years and 50.5% were female. Most students (61.2%) had no prior suturing experience. Upon completion of the course, there was a significant improvement (p = < 0.0001) in comfort level for each of the six skills. Most students (81%) reported an increased interest in surgery. CONCLUSIONS: Early implementation of a basic skills workshop can augment student comfort level and promote an interest in surgery. Peer student mentors can effectively lead the workshop and minimize the time commitment needed by surgical faculty. This can serve as a new direction in medical education and an avenue for further studies to analyze the longitudinal effects of the curriculum on career choice and success in surgical residency.

13.
Ann Med Surg (Lond) ; 48: 122-123, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31763039

RESUMO

BACKGROUND: Understanding basic surgical skills is important for medical students prior to entering residency regardless of future specialty. In these videos we provide instruction for suturing as it relates to skin closure. MATERIAL AND METHODS: Instructional videos were created by the senior faculty (R.A. and M.K.) to teach medical students at the University of Louisville suturing techniques. RESULTS: Entering and exiting the needle at an angle of 90° or greater allows for tissue eversion. Inadequate eversion of tissue or inadequate angling of the needle will lead to tissue inversion. When suturing uneven edges, a deep bite on the low side and a shallow bite on the high side will allow for appropriate tissue leveling. For buried sutures, skin eversion with substantial dermal bites and proper knot location is essential. CONCLUSION: Understanding the basics of skin apposition will provide students with knowledge about primary wound healing and prepare them for residency.

14.
Stud Mycol ; 94: 1-124, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31636728

RESUMO

This paper represents the third contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions, information about the pathology, distribution, hosts and disease symptoms for the treated genera, as well as primary and secondary DNA barcodes for the currently accepted species included in these. This third paper in the GOPHY series treats 21 genera of phytopathogenic fungi and their relatives including: Allophoma, Alternaria, Brunneosphaerella, Elsinoe, Exserohilum, Neosetophoma, Neostagonospora, Nothophoma, Parastagonospora, Phaeosphaeriopsis, Pleiocarpon, Pyrenophora, Ramichloridium, Seifertia, Seiridium, Septoriella, Setophoma, Stagonosporopsis, Stemphylium, Tubakia and Zasmidium. This study includes three new genera, 42 new species, 23 new combinations, four new names, and three typifications of older names.

15.
Eplasty ; 19: e19, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31501688

RESUMO

Introduction: Carpal tunnel syndrome is the most common entrapment neuropathy involving the upper extremity. As such, various nonoperative techniques have been developed to aid in management of mild to moderate disease, including local steroid injection. However, definitive guidelines for needle/injection location have not been defined, especially in relation to diminishment of iatrogenic injury to the median nerve. Methods: A cadaveric study was designed to determine the average width of the median nerve, as well as its location specifically in relation to the palmaris longus (if present), the flexor carpi radialis, and the midpoint of the wrist. All measurements were obtained at the radial tip of the interstyloid line. Results: Data demonstrated that the average width of the median nerve was 7.85 mm and that it lies ulnar in location to the palmaris longus (3 mm), as well as the midpoint of the wrist at the radial tip of the interstyloid line (0.43 mm). Furthermore, the distance between the median nerve and the flexor carpi radialis was measured to be 9.57 mm. Outcomes: Therefore, injection location should be radial with respect to the palmaris longus and the midline of the wrist. It can be just ulnar to the flexor carpi radialis tendon or between 8 and 10 mm radial to the midpoint of the wrist in order to prevent median nerve injection and direct trauma to the nerve.

17.
Eur J Pain ; 23(1): 15-30, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29984553

RESUMO

Previous mass media campaigns have aimed to influence how people manage back pain, with mixed success. Campaigns should target beliefs which are related to the behaviours they aim to change. This systematic review brings together research that has measured the prevalence of beliefs about back pain in the general population and factors associated with these beliefs, including future pain-related outcomes. Five databases were searched up until April 2017. Quantitative studies which reported a measure of agreement with a belief about back pain, cross-sectional associations, or associations between beliefs and future outcomes were eligible. Eligibility was assessed and data extracted independently by two authors. Results were tabulated and narratively synthesized. Nineteen studies from 10 countries were eligible (median study n [IQR] = 990.5 [524.75-2387.5]). Beliefs were measured using eight questionnaires and 57 stand-alone items. Beliefs about back pain's negative consequences were common across countries and populations, whereas most samples did not hold fear-avoidance beliefs. Beliefs about back pain's consequences were associated with pain and disability, but only one study investigated this specific relationship prospectively. No studies investigated whether beliefs are associated with future pain management behaviours. Agreement with certain beliefs (e.g. about negative consequences) was associated with sociodemographic characteristics (e.g. older age) and poorer self-rated health. Interventions may benefit from targeting beliefs about the perceived negative consequences of back pain in these populations. However, future research should explore how beliefs prospectively influence the management of back pain. SIGNIFICANCE: This review brings together studies which have assessed the prevalence of beliefs about back pain, and factors associated with holding them. It highlights that whether or not these beliefs represent important determinants of how people manage pain remains unknown.


Assuntos
Atitude Frente a Saúde , Dor nas Costas/psicologia , Comportamentos Relacionados com a Saúde , Manejo da Dor , Dor nas Costas/terapia , Medo , Humanos , Percepção , Inquéritos e Questionários
19.
Rev Sci Instrum ; 89(10): 10D122, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399666

RESUMO

A beam emission spectroscopy system is being developed and deployed on the HL-2A tokamak to measure local low wavenumber (k ⊥ ρ i < 1) density fluctuations by measuring the Doppler-shifted emission from a 50 kV deuterium heating neutral beam. High spatial resolution (Δr ≤ 1 cm, Δz ≤ 1.5 cm) measurements are achieved with customized in-vacuum optics. High frequency, high-gain preamplifiers sample the light intensity at a Nyquist frequency of 1 MHz and achieve a high S/N ratio via high optical throughput, low-noise preamplifiers, and high quantum efficiency photodiodes. A first set of 16 detector channels [configured in an 8 (radial) × 2 (poloidal) array] has been installed and tested at HL-2A, covering the radial range r/a = 0.8-1.1. The frequency and wavenumber spectra have been measured under different plasma conditions. Initial measurements have demonstrated the capability of measuring edge plasma density fluctuation spectra and the poloidal flow velocity fields with a high S/N ratio.

20.
Implant Dent ; 27(6): 609, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30285994
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