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1.
Cortex ; 171: 204-222, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38029653

RESUMEN

Phonological difficulties have been identified as a core deficit in developmental dyslexia, yet everyday speech comprehension, which relies on phonological processing, is seemingly unaffected. This raises the question as to how dyslexic readers process spoken words to achieve normal word comprehension. Here we establish a link between neural correlates of lexical and sublexical processing in auditory words and behaviourally measured phonological deficits using magnetoencephalography (MEG). Spatiotemporally resolved cortical responses to phonological and lexico-semantic information were computed with the event-related regression technique (Hauk et al., 2009) and correlated with dyslexic and non-dyslexic subjects' phonological skills. We found that phonological deficits reduced cortical responses to both phonological and lexico-semantic information (phonological neighbours and word frequency). Individuals with lower phonological skills - independent of dyslexia diagnosis - showed weaker neural responses to phonological neighbourhood information in both hemispheres 200-500 ms after word onset and reduced sensitivity to written and spoken word frequency between 200 and 650 ms. Dyslexic readers showed weaker responses to written word frequency in particular compared to the control group, pointing towards an additional effect of print exposure on auditory word processing. Source space analysis localised phonological and lexico-semantic effect peaks to the left superior temporal gyrus, a key area that has been related to core deficits in dyslexia across a range of neuroimaging studies. The results provide comprehensive evidence that phonological deficits impact both sublexical and lexical stages of spoken word processing and that these deficits cannot be fully compensated through neural re-organization of lexical-distributional information at the single word level. Theoretical and practical implications for typical readers, dyslexic readers, and readers with developmental language disorder are discussed.


Asunto(s)
Dislexia , Magnetoencefalografía , Humanos , Mapeo Encefálico , Lóbulo Temporal , Habla/fisiología , Lectura , Fonética
2.
J Bacteriol ; 205(4): e0045722, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36920209

RESUMEN

Bacteria have evolved different systems to sense and adapt to acid stress. For example, Vibrio campbellii, a marine pathogen for invertebrates, encounters acidic conditions in the digestive glands of shrimp. The main acid resistance system of V. campbellii is the Cad system, which is activated when cells are in a low-pH, amino acid-rich environment. The Cad system consists of the pH-responsive transcriptional activator CadC, the lysine decarboxylase CadA, and the lysine/cadaverine antiporter CadB. In many Vibrio species, the LysR-type transcriptional regulator AphB is involved in the regulation of the Cad system, but its precise role is unclear. Here, we examined AphB of V. campbellii in vivo and in vitro in the context of Cad activation. At low pH, an aphB deletion mutant was less able to grow and survive compared with the wild-type because it did not excrete sufficient alkaline cadaverine to increase the extracellular pH. AphB was found to upregulate the transcription of cadC, thereby increasing its protein copy number per cell. Moreover, AphB itself was shown to be a pH-sensor, and binding to the cadC promoter increased under low pH, as shown by surface plasmon resonance spectroscopy. By monitoring the activation of the Cad system over a wide range of pH values, we found that AphB-mediated upregulation of cadC not only adjusts CadC copy numbers depending on acid stress strength, but also affects the response of individual cells and thus the degree of heterogeneous Cad system activation in the V. campbellii population. IMPORTANCE Acid resistance is an important property not only for neutralophilic enteric bacteria such as Escherichia, Yersinia, and Salmonella, but also for Vibrio. To counteract acidic threats, the marine Vibrio campbellii, a pathogen for various invertebrates, activates the acid-resistance Cad system. The transcriptional activator of the Cad system is CadC, an extracellular pH-sensor. The expression of cadC is upregulated by the transcriptional regulator AphB to achieve maximum expression of the components of the Cad system. In vitro studies demonstrate that AphB binds more tightly to the DNA under low pH. The interplay of two pH-responsive transcriptional activators allows tight control of the activity of the Cad system.


Asunto(s)
Transactivadores , Vibrio , Transactivadores/genética , Cadaverina , Factores de Transcripción , Vibrio/genética , Vibrio/metabolismo , Proteínas Bacterianas/metabolismo
3.
Molecules ; 28(2)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36677555

RESUMEN

N1,N2-diphenylacenaphthylene-1,2-diimines (BIANs) have been used to reduce the undesired high viscosity of alkyl magnesium solutions, which are known to form polymeric structures. In order to understand the mechanisms, analyses of the BIAN alkyl magnesium solutions have been carried out under inert conditions with SEC-MS, NMR, and FTIR and were compared to the structures obtained from HPLC-MS, FTIR, and NMR after aqueous workup. While viscosity reduction was shown for all BIAN derivatives used, only the bis (diisopropyl)-substituted BIAN could be clearly assigned to a single reaction product, which also could be reused without loss of efficiency or decomposition. All other derivatives have been shown to behave differently, even under inert conditions, and decompose upon contact with acidic solvents. While the chemical reactions observed after the workup of the used BIANs are dominated by (multiple) alkylation, mainly on the C = N double bond, the observation of viscosity reduction cannot be assigned to this reaction alone, but to the interaction of the nitrogen atoms of BIANs with the Mg of the alkyl magnesium polymers, as could be shown by FTIR and NMR measurements under inert conditions.

4.
JAMA Otolaryngol Head Neck Surg ; 149(1): 71-78, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36454583

RESUMEN

Importance: Involvement of deep margins represents a significant challenge in the treatment of oropharyngeal cancer, and given practical limitations of frozen-section analysis, a need exists for real-time, nondestructive intraoperative margin analysis. Wide-field optical coherence tomography (WF-OCT) has been evaluated as a tool for high-resolution adjunct specimen imaging in breast surgery, but its clinical application in head and neck surgery has not been explored. Objective: To evaluate the utility of WF-OCT for visualizing microstructures at margins of excised oral and oropharyngeal tissue. Design, Setting, and Participants: This nonrandomized, investigator-initiated qualitative study evaluated the feasibility of the Perimeter Medical Imaging AI Otis WF-OCT device at a single academic center. Included participants were adults undergoing primary ablative surgery of the oral cavity or oropharynx for squamous cell carcinoma in 2018 and 2019. Data were analyzed in October 2019. Exposures: Patients were treated according to standard surgical care. Freshly resected specimens were imaged with high-resolution WF-OCT prior to routine pathology. Interdisciplinary interpretation was performed to interpret WF-OCT images and compare them with corresponding digitized pathology slides. No clinical decisions were made based on WF-OCT image data. Main Outcomes and Measures: Visual comparisons were performed between WF-OCT images and hematoxylin and eosin slides. Results: A total of 69 specimens were collected and scanned from 53 patients (mean [SD] age, 59.4 [15.2] years; 35 [72.9%] men among 48 patients with demographic data) undergoing oral cavity or oropharynx surgery for squamous cell carcinoma, including 42 tonsillar tissue, 17 base of the tongue, 4 buccal tissue, 3 mandibular, and 3 other specimens. There were 41 malignant specimens (59.4%) and 28 benign specimens (40.6%). In visual comparisons of WF-OCT images and hematoxylin and eosin slides, visual differentiation among mucosa, submucosa, muscle, dysplastic, and benign tissue was possible in real time using WF-OCT images. Microarchitectural features observed in WF-OCT images could be matched with corresponding features within the permanent histology with fidelity. Conclusions and Relevance: This qualitative study found that WF-OCT imaging was feasible for visualizing tissue microarchitecture at the surface of resected tissues and was not associated with changes in specimen integrity or surgical and pathology workflow. These findings suggest that formal clinical studies investigating use of WF-OCT for intraoperative analysis of deep margins in head and neck surgery may be warranted.


Asunto(s)
Carcinoma de Células Escamosas , Tomografía de Coherencia Óptica , Adulto , Masculino , Humanos , Persona de Mediana Edad , Femenino , Tomografía de Coherencia Óptica/métodos , Eosina Amarillenta-(YS) , Hematoxilina , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Boca/patología , Orofaringe/patología
5.
Orthopedics ; 46(1): e27-e30, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36206512

RESUMEN

Accurate and reproducible acetabular component positioning is among the most important technical factors affecting outcomes of total hip arthroplasty. Although several studies have investigated the influence of pelvic tilt and obliquity on functional acetabular anteversion, the effect of pelvic axial rotation has not yet been established. We analyzed a generic simulated pelvis created using preoperative full-body standing and sitting radiographs. A virtual acetabulum was placed in 144 different scenarios of acetabular anteversion and abduction angles. In each scenario, the effects of pelvic tilt and pelvic axial rotation on different combinations of acetabular orientations were assessed. The change in acetabular anteversion was 0.75° for each 1° of pelvic tilt and was most linear in abduction angles of 40°±45°. The change in acetabular anteversion was 0.8° for each 1° of pelvic axial rotation. Surgeons may consider adjusting acetabular anteversion in fixed axial pelvic deformities when the degree of deformity affects functional acetabular positioning, assessed from preoperative standing and sitting weight-bearing radiographs. [Orthopedics. 2023;46(1):e27-e30.].


Asunto(s)
Acetábulo , Artroplastia de Reemplazo de Cadera , Humanos , Acetábulo/diagnóstico por imagen , Acetábulo/cirugía , Rotación , Postura , Pelvis/diagnóstico por imagen , Pelvis/cirugía
6.
Global Spine J ; 13(3): 861-872, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36127159

RESUMEN

STUDY DESIGN: Systematic review and meta-analysis.OBJECTIVESSurgical decompression alone for patients with neurogenic leg pain in the setting of degenerative lumbar scoliosis (DLS) and stenosis is commonly performed, however, there is no summary of evidence for outcomes. METHODS: A systematic search of English language medical literature databases was performed for studies describing outcomes of decompression alone in DLS, defined as Cobb angle >10˚, and 2-year minimum follow-up. Three outcomes were examined: 1) Cobb angle progression, 2) reoperation rate, and 3) ODI and overall satisfaction. Data were pooled and weighted averages were calculated to summarize available evidence. RESULTS: Across 15 studies included in the final analysis, 586 patients were examined. Average preoperative and postoperative Cobb angles were 17.6˚ (Range: 12.7 - 25˚) and 18.0 (range 14.1 - 25˚), respectively. Average change in Cobb angle was an increase of 1.8˚. Overall rate of reoperation ranged from 3 to 33% with an average of 9.7%. Average ODI before surgery, after surgery, and change in scores were 56.4%, 27.2%, and an improvement of 29% respectively. Average from 8 studies that reported patient satisfaction was 71.2%. CONCLUSIONS: Current literature on decompression alone in the setting of DLS is sparse and is not high quality, limited to patients with small magnitude of lumbar coronal Cobb angle, and heterogenous in the type of procedure performed. Based on available evidence, select patients with DLS who undergo decompression alone had minimal progression of Cobb angle, relatively low reoperation rate, and favorable patient-reported outcomes.

7.
Nat Electron ; 6(8): 630-641, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38465017

RESUMEN

Wearable sweat sensors can potentially be used to continuously and non-invasively monitor physicochemical biomarkers that contain information related to disease diagnostics and fitness tracking. However, the development of such autonomous sensors faces a number of challenges including achieving steady sweat extraction for continuous and prolonged monitoring, and addressing the high power demands of multifunctional and complex analysis. Here we report an autonomous wearable biosensor that is powered by a perovskite solar cell and can provide continuous and non-invasive metabolic monitoring. The device uses a flexible quasi-two-dimensional perovskite solar cell module that provides ample power under outdoor and indoor illumination conditions (power conversion efficiency exceeding 31% under indoor light illumination). We show that the wearable device can continuously collect multimodal physicochemical data - glucose, pH, sodium ions, sweat rate, and skin temperature - across indoor and outdoor physical activities for over 12 hours.

8.
Nutrients ; 14(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36145073

RESUMEN

Accurate dietary analysis of energy, nutrient intake, and meal timing in human studies using traditional dietary assessment methods (e.g., food records) is challenging and time-consuming. The widespread use of smartphones, tablets, and nutrition applications (apps) can overcome some of these problems. The objective of this study was to evaluate the validity of an FDDB smartphone app and food database compared with PRODI®-a professional platform for nutritional counselling using the German Nutrient Database. Dietary records were collected from 10 subjects participating in the crossover intermittent fasting trial for 2 weeks at baseline and during the eating timeframe of 8 h (early or late in the course of the day). The FDDB app and database enabled a quicker and less sophisticated analysis of food composition and timing than the PRODI® software. Good agreement between the methods was found for energy and macronutrient intakes, while the FDDB data on most micronutrients and saturated/unsaturated fat intake were unreliable. In contrast to PRODI®, FDDB provided effective assessment of timely compliance, making it a promising tool for chrononutritional studies. Thus, the FDDB app is comparable to the traditional PRODI® dietary assessment method, and can be effectively used in human dietary trials and medical practice for specific goals.


Asunto(s)
Aplicaciones Móviles , Dieta/métodos , Registros de Dieta , Ingestión de Energía , Ayuno , Grasas Insaturadas , Humanos , Micronutrientes , Evaluación Nutricional , Reproducibilidad de los Resultados , Teléfono Inteligente
9.
Front Psychol ; 13: 879156, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35928422

RESUMEN

During the COVID-19 pandemic, questions have been raised about the impact of face masks on communication in classroom settings. However, it is unclear to what extent visual obstruction of the speaker's mouth or changes to the acoustic signal lead to speech processing difficulties, and whether these effects can be mitigated by semantic predictability, i.e., the availability of contextual information. The present study investigated the acoustic and visual effects of face masks on speech intelligibility and processing speed under varying semantic predictability. Twenty-six children (aged 8-12) and twenty-six adults performed an internet-based cued shadowing task, in which they had to repeat aloud the last word of sentences presented in audio-visual format. The results showed that children and adults made more mistakes and responded more slowly when listening to face mask speech compared to speech produced without a face mask. Adults were only significantly affected by face mask speech when both the acoustic and the visual signal were degraded. While acoustic mask effects were similar for children, removal of visual speech cues through the face mask affected children to a lesser degree. However, high semantic predictability reduced audio-visual mask effects, leading to full compensation of the acoustically degraded mask speech in the adult group. Even though children did not fully compensate for face mask speech with high semantic predictability, overall, they still profited from semantic cues in all conditions. Therefore, in classroom settings, strategies that increase contextual information such as building on students' prior knowledge, using keywords, and providing visual aids, are likely to help overcome any adverse face mask effects.

10.
FEMS Microbiol Rev ; 46(6)2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-35906711

RESUMEN

The Earth is home to environments characterized by low pH, including the gastrointestinal tract of vertebrates and large areas of acidic soil. Most bacteria are neutralophiles, but can survive fluctuations in pH. Herein, we review how Escherichia, Salmonella, Helicobacter, Brucella, and other acid-resistant Gram-negative bacteria adapt to acidic environments. We discuss the constitutive and inducible defense mechanisms that promote survival, including proton-consuming or ammonia-producing processes, cellular remodeling affecting membranes and chaperones, and chemotaxis. We provide insights into how Gram-negative bacteria sense environmental acidity using membrane-integrated and cytosolic pH sensors. Finally, we address in more detail the powerful proton-consuming decarboxylase systems by examining the phylogeny of their regulatory components and their collective functionality in a population.


Asunto(s)
Bacterias , Protones , Animales , Ácidos , Adaptación Fisiológica , Membrana Celular , Concentración de Iones de Hidrógeno
11.
Gynecol Oncol Rep ; 40: 100948, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35265744

RESUMEN

Objective: Previvors are becoming more aware of the option of risk-reducing salpingectomy with delayed oophorectomy (RRS-DO) to mitigate their risk of ovarian cancer. In this qualitative study, we explored the clinical and non-clinical factors that impacted previvors' decision-making to pursue RRS-DO as a risk reduction strategy. Methods: Semi-structured telephone interviews were conducted with previvors and transcribed verbatim. Using ATLAS.ti® software, two primary investigators interpreted data through thematic analysis. After coding four interviews, the investigators discussed discrepancies between codes with a moderator and resolved and refined code. The investigators applied the universal codebook to all interviews and revised the codebook using an iterative approach. Examining codes within and across interviews allowed for major themes and patterns to emerge. Results: Interviews were conducted with seventeen previvors (ages 31-46). 6 (25%) previvors had a BRCA1 mutation, 7 (41%), a BRCA2 mutation, 3 (13%), a Lynch-related mutation, and 1 (6%), other (MUTYH mutation). At the time of interview, 12 previvors (71%) were planning (6) or had undergone (6) RRS-DO, 4 (23%) were planning (1) or had undergone (3) risk reducing salpingo-oophorectomy (RRSO), and 1 (6%) was undecided. Three major themes emerged: motivating factors for selecting surgical risk reduction option, barriers complicating surgical decision-making, and facilitating factors for surgical decision-making. RRS-DO-focused previvors prioritized avoiding menopause, and they also emphasized that self-advocacy and building rapport with providers facilitated their decision-making. Conclusion: By understanding previvors' priorities and experiences, physicians can better partner with previvors as they navigate their ovarian cancer risk reduction journey. This will ultimately optimize shared decision-making.

12.
Vet Rec Open ; 9(1): e24, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35111328

RESUMEN

BACKGROUND: An outbreak of salmonellosis due to Salmonella Typhimurium was detected coincidentally in a Swiss meat rabbitry, given that surveillance of Salmonella in rabbits is not mandatory in Switzerland. METHODS: To assess the extent of potentially subclinical Salmonella carriage in meat rabbits, faecal pool samples of 50 farms (90% of Swiss commercial rabbitries) with ground covering litter and group housing were bacteriologically tested. Additionally, 236 rabbits showing clinical signs compatible with intestinal diseases, such as salmonellosis, were examined postmortem and analysed bacteriologically. Salmonella isolates were serotyped and analysed by whole genome sequencing (WGS). RESULTS: Salmonella Typhimurium was detected in three commercial farms (6.0% of all tested farms). The affected farms were directly linked to the animal trade and Salmonella isolates were shown to be identical by WGS. CONCLUSION: There is no increased hazard for Salmonella carriage in the animal welfare-friendly Swiss husbandry systems in general, despite risk factors such as ground covering litter.

13.
Sci Adv ; 7(51): eabk1643, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34919425

RESUMEN

Extreme climatic events threaten forests and their climate mitigation potential globally. Understanding the drivers promoting ecosystem stability is therefore considered crucial for mitigating adverse climate change effects on forests. Here, we use structural equation models to explain how tree species richness, asynchronous species dynamics, species-level population stability, and drought-tolerance traits relate to the stability of forest productivity along an experimentally manipulated species richness gradient ranging from 1 to 24 tree species. Tree species richness improved community stability by increasing asynchrony. That is, at higher species richness, interannual variation in productivity among tree species buffered the community against stress-related productivity declines. This effect was positively related to variation in stomatal control and resistance-acquisition strategies among species, but not to the community-weighted means of these trait syndromes. The identified mechanisms by which tree species richness stabilizes forest productivity emphasize the importance of diverse, mixed-species forests to adapt to climate change.

14.
Front Nutr ; 8: 662310, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34395487

RESUMEN

Background: Religiously motivated Bahá'í fasting (BF) is a form of intermittent dry fasting celebrated by abstaining from food and drinks during daylight hours every year in March for 19 consecutive days. Aim: To test the safety and effects of BF on hydration, metabolism, and the circadian clock. Methods: Thirty-four healthy Bahá'í volunteers (15 women) participated in this prospective, exploratory cohort study. Laboratory examinations were carried out in four study visits: before fasting (V0), in the third week of fasting (V1) as well as 3 weeks (V3) and 3 months (V4) after fasting. Data collection included blood and urine samples, anthropometric measurements and bioelectrical impedance analysis. At V0 and V1, 24- and 12-hour urine and serum osmolality were measured. At V0-V2, alterations in the circadian clock phase were monitored in 16 participants. Our study was augmented by an additional survey with 144 healthy Bahá'í volunteers filling out questionnaires and with subgroups attending metabolic measurements (n = 11) and qualitative interviews (n = 13), the results of which will be published separately. Results: Exploratory data analysis revealed that serum osmolality (n = 34, p < 0.001) and 24-hour urine osmolality (n = 34, p = 0.003) decreased during daytime fasting but remained largely within the physiological range and returned to pre-fasting levels during night hours. BMI (body mass index), total body fat mass, and resting metabolic rate decreased during fasting (n = 34, p < 0.001), while body cell mass and body water appeared unchanged. The circadian phase estimated by transcript biomarkers of blood monocytes advanced by 1.1 h (n = 16, p < 0.005) during fasting and returned to pre-fasting values 3 weeks after fasting. Most observed changes were not detectable anymore 3 months after fasting. Conclusions: Results indicate that BF (Bahá'í fasting) is safe, has no negative effects on hydration, can improve fat metabolism and can cause transient phase shifts of circadian rhythms. Trial Registration:https://www.clinicaltrials.gov/, identifier: NCT03443739.

15.
J Arthroplasty ; 36(10): 3551-3555, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34175193

RESUMEN

BACKGROUND: Registry data suggest increasing rates of early revisions after total hip arthroplasty (THA). We sought to analyze modes of failure over time after index THA to identify risk factors for early revision. METHODS: We identified 208 aseptic femoral revision THAs performed between February 2011 and July 2019 using an institutional database. We compared demographics, diagnoses, complications, and resource utilization between aseptic femoral revision THA occurring within 90 days (early), 91 days to 2 years (mid), and greater than 2 years (late) after index arthroplasty. RESULTS: Early revisions were 33% of revisions at our institution in the time period analyzed. Periprosthetic fractures were 81% of early, 27% of mid, and 21% of late femoral revisions (P < .01). Women were more likely to have early revisions than men (75% vs 53% of mid and 48% of late revisions; P < .01). Patients who had early revisions were older (67.97 ± 10.06) at the time of primary surgery than those who had mid and late revisions (64.41 ± 12.10 and 57.63 ± 12.52, respectively, P < .01). Index implants were uncemented in 99% of early, 96% of mid, and 64% of late revisions (P < .01). Early revisions had longer postoperative length of stay (4.4 ± 3.3) than mid and late revisions (3.0 ± 2.2 and 3.7 ± 2.1, respectively, P = .02). In addition, 58% of early revisions were discharged to an inpatient facility compared with 36% of mid and 41% of late revisions (P = .03). CONCLUSION: Early aseptic femoral revisions largely occur in older women with uncemented primary implants and primarily due to periprosthetic fractures. Reducing the incidence of periprosthetic fractures is critical to decreasing the large health care utilization of early revisions.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Femenino , Fémur/cirugía , Prótesis de Cadera/efectos adversos , Humanos , Masculino , Diseño de Prótesis , Falla de Prótesis , Reoperación , Estudios Retrospectivos , Factores de Riesgo
16.
Glob Chang Biol ; 27(18): 4403-4419, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34166562

RESUMEN

Extreme droughts are expected to increase in frequency and severity in many regions of the world, threatening multiple ecosystem services provided by forests. Effective strategies to adapt forests to such droughts require comprehensive information on the effects and importance of the factors influencing forest resistance and resilience. We used a unique combination of inventory and dendrochronological data from a long-term (>30 years) silvicultural experiment in mixed silver fir and Norway spruce mountain forests along a temperature and precipitation gradient in southwestern Germany. We aimed at examining the mechanisms and forest stand characteristics underpinning the resistance and resilience to past mild and severe droughts. We found that (i) fir benefited from mild droughts and showed higher resistance (i.e., lower growth loss during drought) and resilience (i.e., faster return to pre-drought growth levels) than spruce to all droughts; (ii) species identity determined mild drought responses while species interactions and management-related factors strongly influenced the responses to severe droughts; (iii) intraspecific and interspecific interactions had contrasting effects on the two species, with spruce being less resistant to severe droughts when exposed to interaction with fir and beech; (iv) higher values of residual stand basal area following thinning were associated with lower resistance and resilience to severe droughts; and (v) larger trees were resilient to mild drought events but highly vulnerable to severe droughts. Our study provides an analytical approach for examining the effects of different factors on individual tree- and stand-level drought response. The forests investigated here were to a certain extent resilient to mild droughts, and even benefited from such conditions, but were strongly affected by severe droughts. Lastly, negative effects of severe droughts can be reduced through modifying species composition, tree size distribution and stand density in mixed silver fir-Norway spruce forests.


Asunto(s)
Sequías , Ecosistema , Cambio Climático , Europa (Continente) , Bosques , Noruega
17.
PLoS Negl Trop Dis ; 15(4): e0009307, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33901172

RESUMEN

Rapid diagnostic tests (RDTs) have the potential to identify infectious diseases quickly, minimize disease transmission, and could complement and improve surveillance and control of infectious and vector-borne diseases during outbreaks. The U.S. Defense Threat Reduction Agency's Joint Science and Technology Office (DTRA-JSTO) program set out to develop novel point-of-need RDTs for infectious diseases and deploy them for home use with no training. The aim of this formative study was to address two questions: 1) could community members in Iquitos, Peru and Phnom Penh, Cambodia competently use RDTs of different levels of complexity at home with visually based instructions provided, and 2) if an RDT were provided at no cost, would it be used at home if family members displayed febrile symptoms? Test kits with written and video (Peru only) instructions were provided to community members (Peru [n = 202]; Cambodia [n = 50]) or community health workers (Cambodia [n = 45]), and trained observers evaluated the competency level for each of the several steps required to successfully operate one of two multiplex RDTs on themselves or other consenting participant (i.e., family member). In Iquitos, >80% of residents were able to perform 11/12 steps and 7/15 steps for the two- and five-pathogen test, respectively. Competency in Phnom Penh never reached 80% for any of the 12 or 15 steps for either test; the percentage of participants able to perform a step ranged from 26-76% and 23-72%, for the two- and five-pathogen tests, respectively. Commercially available NS1 dengue rapid tests were distributed, at no cost, to households with confirmed exposure to dengue or Zika virus; of 14 febrile cases reported, six used the provided RDT. Our findings support the need for further implementation research on the appropriate level of instructions or training needed for diverse devices in different settings, as well as how to best integrate RDTs into existing local public health and disease surveillance programs at a large scale.


Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/normas , Personal de Salud/educación , Adolescente , Adulto , Cambodia , Dengue/diagnóstico , Educación/métodos , Femenino , Grupos Focales , Instituciones de Salud , Conocimientos, Actitudes y Práctica en Salud , Investigación sobre Servicios de Salud , Humanos , Malaria/diagnóstico , Masculino , Melioidosis/diagnóstico , Persona de Mediana Edad , Aceptación de la Atención de Salud , Perú , Peste/diagnóstico , Manejo de Especímenes/métodos , Adulto Joven
18.
Bull Hosp Jt Dis (2013) ; 79(1): 51-57, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33704038

RESUMEN

The anterior approach has become a widely used and accepted approach for total hip arthroplasty (THA). This approach offers a number of advantages including supine positioning, improved soft tissue management, and avoidance of taking down posterior structures. The approach has evolved significantly from its introduction in the late 19th Century due to advancements in technology. Specifically, developments in the table used for the approach, safer instrumentation, and fluoroscopic guidance with overlay technologies have helped the anterior approach gain popularity. This article reviews the evolution of the usage of the anterior approach, including the use of current and emerging technologies as well as the learning curve associated with switching to the anterior THA and the future of outpatient anterior THA.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Fluoroscopía , Humanos , Curva de Aprendizaje , Estudios Retrospectivos
19.
Sci Rep ; 11(1): 5149, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664306

RESUMEN

Climate change is expected to pose major direct and indirect threats to groundwater-dependent forest ecosystems. Forests that concurrently experience increased rates of water extraction may face unprecedented exposure to droughts. Here, we examined differences in stem growth and xylem hydraulic architecture of 216 oak trees from sites with contrasting groundwater availability, including sites where groundwater extraction has led to reduced water availability for trees over several decades. We expected reduced growth and xylem hydraulic capacity for trees at groundwater extraction sites both under normal and unfavourable growing conditions. Compared to sites without extraction, trees at sites with groundwater extraction showed reduced growth and hydraulic conductivity both during periods of moderate and extremely low soil water availability. Trees of low vigour, which were more frequent at sites with groundwater extraction, were not able to recover growth and hydraulic capacity following drought, pointing to prolonged drought effects. Long-term water deficit resulting in reduced CO2 assimilation and hydraulic capacity after drought are very likely responsible for observed reductions in tree vitality at extraction sites. Our results demonstrate that groundwater access maintains tree function and resilience to drought and is therefore important for tree health in the context of climate change.

20.
Front Vet Sci ; 8: 595455, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33748204

RESUMEN

Objective: To assess the inter-evaluator and intra-evaluator reliability of a software program used to extract kinematic variables by a commercially available extremity-mounted inertial measurement unit system in sound horses at the trot under soft and hard ground conditions and treadmill exercise. Animals: Thirty adult, sound and healthy French Montagne stallions. Procedures: Data collection was performed with six IMUs strapped to the distal, metacarpal, metatarsal and tibial regions of every horse. Per surface (treadmill, soft and hard ground) 10 stallions were trotted three times. Prior to the analysis done by six evaluators (three experienced, three inexperienced) the data was blinded and copied three times. For every analysis a minimum of five strides had to be selected. To assess the intra- and inter-evaluator reliability a selection of gait variables was used to calculate intra and inter correlation coefficients (ICCs) as well as variance partitioning coefficients (VPCs). Results: All of the tested gait variables showed high levels of reliability. There was no mentionable difference considering the correlation coefficients between the intra and inter reliability as well as between the three different surfaces. VPCs showed that the factor horse is by far the most responsible for any appearing variance. The experience of the evaluator had no influence on the results. Conclusions and Clinical Relevance: The software program tested in this study has a high inter- and intra-evaluator reliability under the chosen conditions for the selected variables and acts independent of the ground situation and the experience of the evaluator. On the condition of a correct application it has the potential to become a clinically relevant and reliable gait analysis tool.

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