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1.
J Plast Reconstr Aesthet Surg ; 91: 258-267, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38428234

RESUMEN

INTRODUCTION: Advances in burns management have reduced mortality. Consequently, efficient resource management plays an increasingly important role in improving paediatric burns care. This study aims to assess the support requirements and outcomes of paediatric burns patients admitted to a burns centre intensive care unit in comparison to established benchmarks in burns care. METHOD: A retrospective review of burns patients under the age of 16 years old, admitted to a regional burns service intensive care unit between March 1998 and March 2016 was conducted. RESULTS: Our analysis included 234 patients, with the percentage of TBSA affected by burn injury ranging from 1.5% to 95.0%. The median (IQR) %TBSA was 20.0% (11.0-30.0), and the observed mortality rate was 2.6% (6/234). The median (IQR) length of stay was 0.7 days/%TBSA burn (0.4-1.2), 17.9% (41/229) required circulatory support and 2.6% (6/234) required renal replacement. Mortality correlated with smoke inhalation injury (P < 0.001), %TBSA burn (P = 0.049) and complications (P = 0.004) including infections (P = 0.013). CONCLUSIONS: Among children with burn injuries who require intensive care, the presence of inhalational injury and the diagnosis of infection are positively correlated with mortality. Understanding the requirements for organ support can facilitate a more effective allocation of resources within a burns service.


Asunto(s)
Quemaduras , Unidades de Cuidados Intensivos , Humanos , Niño , Adolescente , Tiempo de Internación , Cuidados Críticos , Hospitalización , Unidades de Quemados , Estudios Retrospectivos , Quemaduras/complicaciones
2.
Mar Environ Res ; 194: 106341, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38183736

RESUMEN

Marine ecosystems in Antarctica are thought to be highly vulnerable to aspects of dynamic global climate change, such as warming. In deep-water ecosystems, there has been little physico-chemical change in seawater there for millions of years. Thus, some benthic organisms are likely to include strong potential indicators of environmental changes and give early warnings of ecosystem vulnerability. In 2017 we sampled deep-water benthic assemblages across a continental shelf trough in outer Marguerite Bay, West Antarctic Peninsula (WAP). This region is one of the hotspots of climate-related physical change on Earth in terms of seasonal sea ice loss. Video and images of the seabed were captured at 5 stations, each with 20 replicates. From these, we identified substratum types and biota to functional groups to assess variability in benthic composition and diversity. We also collected coincident environmental information on depth, temperature, salinity, oxygen and chlorophyll-a (using a CTD). Climax sessile suspension feeders were the most spatially dominant group, comprising 539 individuals (39% of total abundance) that included Porifera, Brachiopoda and erect Bryozoa. ST5, the shallowest station was functionally contrasting with other stations. This functional difference was also influenced by hard substrata of ST5, which is typically preferred by climax sessile suspension feeders. Depth (or an associated driver) and hard substrates were the most apparent key factor which functionally characterised the communities, shown by the abundance of climax sessile suspension feeders. Our study showed that non-invasive, low taxonomic skill requirement, functional group approach is not only valuable in providing functional perspective on environment status, but such groupings also proved to be sensitive to environmental variability.


Asunto(s)
Ecosistema , Invertebrados , Humanos , Animales , Regiones Antárticas , Cambio Climático , Agua
3.
Mil Med ; 188(Suppl 6): 393-399, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37948210

RESUMEN

INTRODUCTION: Combat-related injuries from improvised explosive devices occur commonly to the lower extremity and spine. As the underbody blast impact loading traverses from the seat to pelvis to spine, energy transfer occurs through deformations of the combined pelvis-sacrum-lumbar spine complex, and the time factor plays a role in injury to any of these components. Previous studies have largely ignored the role of the time variable in injuries, injury mechanisms, and warfighter tolerance. The objective of this study is to relate the time or temporal factor using a multi-component, pelvis-sacrum-lumbar spinal column complex model. MATERIALS AND METHODS: Intact pelvis-sacrum-spine specimens from pre-screened unembalmed human cadavers were prepared by fixing at the superior end of the lumbar spine, pelvis and abdominal contents were simulated, and a weight was added to the cranial end of the fixation to account for torso effective mass. Prepared specimens were placed on the platform of a custom vertical accelerator device and aligned in a seated soldier posture. An accelerometer was attached to the seat platen of the device to record the time duration to peak velocity. Radiographs and computed tomography images were used to document and associate injuries with time duration. RESULTS: The mean age, stature, weight, body mass index, and bone density of 12 male specimens were as follows: 65 ± 11 years, 1.8 ± 0.01 m, 83 ± 13 kg, 27 ± 5.0 kg/m2, and 114 ± 21 mg/cc. They were equally divided into short, medium, and long time durations: 4.8 ± 0.5, 16.3 ± 7.3, and 34.5 ± 7.5 ms. Most severe injuries associated with the short time duration were to pelvis, although they were to spine for the long time duration. CONCLUSIONS: With adequate time for the underbody blast loading to traverse the pelvis-sacrum-spine complex, distal structures are spared while proximal/spine structures sustain severe/unstable injuries. The time factor may have implications in seat and/or seat structure design in future military vehicles to advance warfighter safety.


Asunto(s)
Traumatismos por Explosión , Traumatismos Vertebrales , Humanos , Masculino , Persona de Mediana Edad , Anciano , Sacro/lesiones , Traumatismos Vertebrales/etiología , Explosiones , Pelvis/lesiones , Vértebras Lumbares , Cadáver , Fenómenos Biomecánicos
4.
Res Vet Sci ; 164: 105030, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37788548

RESUMEN

We describe the genetic diversity and phylogenetic relationships of Mycobacterium bovis, isolated from cattle in Malawi. Deletion analysis, spoligotyping, and MIRU-VNTR typing were used to genotype the isolates. Combined with a larger dataset from neighboring countries, the overall M. bovis diversity in Southern Africa was contextualized. From the southern and northern regions of Malawi, 24 isolates were confirmed as M. bovis. We pooled data for the central region (60 isolates) from our recent publication to conceptualize the genetic and phylogenetic relationships of M. bovis in Malawi. European 1 was the dominant M. bovis clonal complex, with 10 unique spoligotype patterns, and SB0131 was ubiquitous. High genetic diversity, a low clustering rate, and many singletons, coupled with a low mutation transmission index, infer a low level of recent transmission, and suggest an endemic status of bovine tuberculosis (bTB) in Malawi. M. bovis isolates from Zambia, Mozambique, and South Africa were genetically related to Malawian isolates, whereas Tanzanian isolates were distantly related. The diversity and phylogenetic analysis suggest earlier introductions and maintenance of M. bovis by constant reinfection from reservoir animals. These findings are fundamental to understanding the source and route of infection in order to establish alternative management strategies for bTB.


Asunto(s)
Enfermedades de los Bovinos , Mycobacterium bovis , Tuberculosis Bovina , Animales , Bovinos , Mycobacterium bovis/genética , Malaui/epidemiología , Filogenia , Variación Genética , Tuberculosis Bovina/microbiología , Genotipo , Repeticiones de Minisatélite , Técnicas de Tipificación Bacteriana/veterinaria , Enfermedades de los Bovinos/genética
5.
Vaccines (Basel) ; 11(9)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37766138

RESUMEN

Mucosal IgA is widely accepted as providing protection against respiratory infections, but stimulation of mucosal immunity, collection of mucosal samples and measurement of mucosal IgA can be problematic. The relationship between mucosal and circulating IgA responses is unclear, however, whole blood is readily collected and circulating antigen-specific IgA easily measured. We measured circulating IgA against SARS-CoV-2 spike (S) to investigate vaccine- and infection-induced production and correlation with protection. Circulating IgA against ancestral (Wuhan-Hu-1) and Omicron (BA.1) S proteins was measured at different time points in a total of 143 subjects with varied backgrounds of vaccination and infection. Intramuscular vaccination induced circulating anti-SARS-CoV-2 S IgA. Subjects with higher levels of vaccine-induced IgA against SARS-CoV-2 S (p = 0.0333) or receptor binding domain (RBD) (p = 0.0266) were less likely to experience an Omicron breakthrough infection. The same associations did not hold for circulating IgG anti-SARS-CoV-2 S levels. Breakthrough infection following two vaccinations generated stronger IgA anti-SARS-CoV-2 S responses (p = 0.0002) than third vaccinations but did not selectively increase circulating IgA against Omicron over ancestral S, indicating immune imprinting of circulating IgA responses. Circulating IgA against SARS-CoV-2 S following breakthrough infection remained higher than vaccine-induced levels for over 150 days. In conclusion, intramuscular mRNA vaccination induces circulating IgA against SARS-CoV-2 S, and higher levels are associated with protection from breakthrough infection. Vaccination with ancestral S enacts imprinting within circulating IgA responses that become apparent after breakthrough infection with Omicron. Breakthrough infection generates stronger and more durable circulating IgA responses against SARS-CoV-2 S than vaccination alone.

6.
Sci Total Environ ; 903: 166157, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37572912

RESUMEN

The marine habitat beneath Antarctica's ice shelves spans ∼1.6 million km2, and life in this vast and extreme environment is among Earth's least accessible, least disturbed and least known, yet likely to be impacted by climate-forced warming and environmental change. Although competition among biota is a fundamental structuring force of ecological communities, hence ecosystem functions and services, nothing was known of competition for resources under ice shelves, until this study. Boreholes drilled through a âˆ¼ 200 m thick ice shelf enabled collections of novel sub-ice-shelf seabed sediment which contained fragments of biogenic substrata rich in encrusting (lithophilic) macrobenthos, principally bryozoans - a globally-ubiquitous phylum sensitive to environmental change. Analysis of sub-glacial biogenic substrata, by stereo microscopy, provided first evidence of spatial contest competition, enabling generation of a new range of competition measures for the sub-ice-shelf benthic space. Measures were compared with those of global open-water datasets traversing polar, temperate and tropical latitudes (and encompassing both hemispheres). Spatial competition in sub-ice-shelf samples was found to be higher in intensity and severity than all other global means. The likelihood of sub-ice-shelf competition being intraspecific was three times lower than for open-sea polar continental shelf areas, and competition complexity, in terms of the number of different types of competitor pairings, was two-fold higher. As posited for an enduring disturbance minimum, a specific bryozoan clade was especially competitively dominant in sub-ice-shelf samples compared with both contemporary and fossil assemblage records. Overall, spatial competition under an Antarctic ice shelf, as characterised by bryozoan interactions, was strikingly different from that of open-sea polar continental shelf sites, and more closely resembled tropical and temperate latitudes. This study represents the first analysis of sub-ice-shelf macrobenthic spatial competition and provides a new ecological baseline for exploring, monitoring and comparing ecosystem response to environmental change in a warming world.

7.
Commun Biol ; 6(1): 690, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402788

RESUMEN

Competitive hierarchies in diverse ecological communities have long been thought to lead to instability and prevent coexistence. However, system stability has never been tested, and the relation between hierarchy and instability has never been explained in complex competition networks parameterised with data from direct observation. Here we test model stability of 30 multispecies bryozoan assemblages, using estimates of energy loss from observed interference competition to parameterise both the inter- and intraspecific interactions in the competition networks. We find that all competition networks are unstable. However, instability is mitigated considerably by asymmetries in the energy loss rates brought about by hierarchies of strong and weak competitors. This asymmetric organisation results in asymmetries in the interaction strengths, which reduces instability by keeping the weight of short (positive) and longer (positive and negative) feedback loops low. Our results support the idea that interference competition leads to instability and exclusion but demonstrate that this is not because of, but despite, competitive hierarchy.


Asunto(s)
Ecosistema , Retroalimentación
8.
Antibiotics (Basel) ; 12(7)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37508222

RESUMEN

The emergence of pre-extensively drug-resistant tuberculosis (pre-XDR-TB) is a threat to TB control programs in developing countries such as Zambia. Studies in Zambia have applied molecular techniques to understand drug-resistance-associated mutations, circulating lineages and transmission patterns of multi-drug-resistant (MDR) Mycobacterium tuberculosis. However, none has reported genotypes and mutations associated with pre-XDR TB. This study characterized 63 drug-resistant M. tuberculosis strains from the University Teaching Hospital between 2018 and 2019 using targeted gene sequencing and conveniently selected 50 strains for whole genome sequencing. Sixty strains had resistance mutations associated to MDR, one polyresistant, and two rifampicin resistant. Among MDR strains, seven percent (4/60) had mutations associated with pre-XDR-TB. While four, one and nine strains had mutations associated with ethionamide, para-amino-salicylic acid and streptomycin resistances, respectively. All 50 strains belonged to lineage 4 with the predominant sub-lineage 4.3.4.2.1 (38%). Three of four pre-XDR strains belonged to sub-lineage 4.3.4.2.1. Sub-lineage 4.3.4.2.1 strains were less clustered when compared to sub-lineages L4.9.1 and L4.3.4.1 based on single nucleotide polymorphism differences. The finding that resistances to second-line drugs have emerged among MDR-TB is a threat to TB control. Hence, the study recommends a strengthened routine drug susceptibility testing for second-line TB drugs to stop the progression of pre-XDR to XDR-TB and improve patient treatment outcomes.

9.
Curr Issues Mol Biol ; 45(7): 6055-6066, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37504298

RESUMEN

Bovine tuberculosis is endemic in Nigeria with control measures as provided by the laws of the country being minimally enforced mostly at the abattoirs only. This study focused on bovine tuberculosis in Adamawa and Gombe States. Tuberculosis lesions were observed in 183 of 13,688 slaughtered cattle in the regions between June and December 2020. Analysis of tissue samples resulted in 17 Mycobacterium bovis isolates, predominantly from Gombe State. Spoligotyping identified four spoligotypes, including SB0944, SB1025, SB1104, and one novel pattern. MIRU-VNTR analysis further differentiated these spoligotypes into eight profiles. All isolates belonged to the Af1 clonal complex. The study emphasises the need for broader coverage and more isolates to comprehensively understand the molecular epidemiology of bovine tuberculosis in Nigeria. To enhance research and surveillance, a cost-effective approach is proposed, utilising a discriminatory VNTR panel comprising five or nine loci. The five-locus panel consists of ETR-C, QUB26, QUB11b, MIRU04, and QUB323. Alternatively, the nine-locus panel includes ETR-A, ETR-B, QUB11a, and MIRU26. Implementing this approach would provide valuable insights into the genetic diversity of M. bovis strains in Nigeria. These findings are crucial for developing effective control measures and minimising the impact of bovine tuberculosis on both animal and human health.

10.
Clin Pract Cases Emerg Med ; 7(2): 97-100, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37285493

RESUMEN

INTRODUCTION: Tension pneumomediastinum and coronary artery thrombosis (CAT) secondary to blunt polytrauma are, rare yet have the potential for serious complication. CASE REPORT: A 40-year-old man presented to the emergency department following a motorcycle accident. He was found to have multiple orthopedic injuries, pneumothorax, and pneumomediastinum. An electrocardiogram showed myocardial infarction. He developed obstructive shock physiology that resolved with mediastinal percutaneous needle drainage. Subsequent coronary angiography revealed acute thrombosis of the left circumflex artery. CONCLUSION: This is a rare case of traumatic tension pneumomediastinum associated with coronary artery thrombosis requiring coronary stenting. Emergency physicians should be mindful of CAT in the setting of blunt chest injury.

11.
J Plast Reconstr Aesthet Surg ; 83: 282-288, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37290369

RESUMEN

Nitrous oxide is used as a recreational drug. Contact frostbite injury from compressed gas canisters has previously been described in the literature, but an increased number of such cases has been noted in our busy regional burns center in the UK. A single-center prospective case series of all patients referred and treated for frostbite injury secondary to misuse of nitrous oxide compressed gas canisters between January and December 2022 is presented. Data collection was performed through a referral database and patient case notes. Sixteen patients, of which 7 were male and 9 were female, satisfied the inclusion criteria. Mean patient age was 22.5 years. The median TBSA was 1%. In total, 50% of patients in the cohort had a delayed initial presentation to A&E of greater than 5 days. Eleven patients were reviewed at our burns center for further assessment and management. In total, 11 patients had bilateral inner thigh frostbite injuries, of which 8 had necrotic full-thickness injury, including subcutaneous fat. Seven patients were reviewed at our burns center and offered excision and split-thickness skin graft. Four patients presented with contact frostbite injury to the hand and one patient to the lower lip. This subgroup was managed successfully with conservative management alone. The reproducible pattern of frostbite injury secondary to the abuse of nitrous oxide compressed gas canisters is demonstrated in our case series. The distinct pattern of injury, patient cohort, and anatomical area affected presents an opportunity for targeted public health intervention in this group.


Asunto(s)
Quemaduras , Congelación de Extremidades , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Óxido Nitroso/efectos adversos , Quemaduras/terapia , Congelación de Extremidades/inducido químicamente , Congelación de Extremidades/terapia , Trasplante de Piel , Reino Unido
12.
Mar Pollut Bull ; 193: 115144, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37331274

RESUMEN

Microplastics are ubiquitous around the world. Microplastics have been documented around the Southern Ocean, in coastal sediments and in Antarctic marine organisms, however microplastics data for Antarctic waters remain scarce. Microplastics concentrations were characterized from fjord habitats on the Western Antarctic Peninsula where most glaciers are rapidly retreating. Water samples were collected from 2017 to 2020 from surface and benthos, vacuum-filtered, quantified to determine the classification of microplastic, color, and size. Micro-FTIR spectrophotometry was utilized to confirm chemical composition. Comparisons over time and location were made for average microplastic per liter. Despite the new emergent youth and remoteness of these habitats, it was determined that all fjord habitats had microplastics present each year sampled and increased from 2017 to 2020 in each fjord. Despite physical 'barriers' such as the Antarctic Circumpolar Current (and particularly its strongest jet, the Polar Front), microplastics are clearly present and increasing in even recent habitats.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Estuarios , Regiones Antárticas , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Ecosistema
13.
J Environ Manage ; 345: 118325, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390730

RESUMEN

Spatial management of the deep sea is challenging due to limited available data on the distribution of species and habitats to support decision making. In the well-studied North Atlantic, predictive models of species distribution and habitat suitability have been used to fill data gaps and support sustainable management. In the South Atlantic and other poorly studied regions, this is not possible due to a massive lack of data. In this study, we investigated whether models constructed in data-rich areas can be used to inform data-poor regions (with otherwise similar environmental conditions). We used a novel model transfer approach to identify to what extent a habitat suitability model for Desmophyllum pertusum reef, built in a data-rich basin (North Atlantic), could be transferred usefully to a data-poor basin (South Atlantic). The transferred model was built using the Maximum Entropy algorithm and constructed with 227 presence and 3064 pseudo-absence points, and 200 m resolution environmental grids. Performance in the transferred region was validated using an independent dataset of D. pertusum presences and absences, with assessments made using both threshold-dependent and -independent metrics. We found that a model for D. pertusum reef fitted to North Atlantic data transferred reasonably well to the South Atlantic basin, with an area under the curve of 0.70. Suitable habitat for D. pertusum reef was predicted on 20 of the assessed 27 features including seamounts. Nationally managed Marine Protected Areas provide significant protection for D. pertusum reef habitat in the region, affording full protection from bottom trawling to 14 of the 20 suitable features. In areas beyond national jurisdiction (ABNJ), we found four seamounts that provided suitable habitat for D. pertusum reef to be at least partially protected from bottom trawling, whilst two did not fall within fisheries closures. There are factors to consider when developing models for transfer including data resolution and predictor type. Nevertheless, the promising results of this application demonstrate that model transfer approaches stand to provide significant contributions to spatial planning processes through provision of new, best available data. This is particularly true for ABNJ and areas that have previously undergone little scientific exploration such as the global south.


Asunto(s)
Algoritmos , Ecosistema , Explotaciones Pesqueras , Arrecifes de Coral
14.
Soft comput ; : 1-19, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37362292

RESUMEN

With the recent focus on supply risk management in sustainable supply chains, it is more important than ever to evaluate and select the right sustainable suppliers from a supply risk perspective. However, few existing studies consider supply risks from the perspective of all three triple-bottom-line dimensions at the same time. To bridge this research gap, this research constructs a supply risk perspective integrated sustainable supplier selection model in the intuitionistic fuzzy environment. First of all, the weights of decision-makers in the decision-making group are obtained by intuitionistic fuzzy set. Secondly, after obtaining the aggregated intuitionistic fuzzy decision matrix considering the weight of decision-makers, the fuzzy entropy weight method is used to calculate criteria weight, objectively. Then, an improved failure mode and effects analysis is used to undertake risk assessments and to identify high-risk suppliers. Last but not least, the extended alternative queuing method is adopted to rank the eligible sustainable suppliers in the intuitionistic fuzzy environment. The proposed model not only reduces the uncertainty of decision-making in sustainable supplier selection, but also enables focal companies to reduce supply risk in their sustainable supplier selection practices and prevent the failure modes that relate to supply risk. The practicality and effectiveness of the proposed model are verified through an empirical illustration in a leading electrical appliance manufacturer in China.

15.
AEM Educ Train ; 7(Suppl 1): S33-S40, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37383837

RESUMEN

Background: The completion of a scholarly project is a common program requirement by the Accreditation Council for Graduate Medical Education (ACGME) for all residency training programs. However, the implementation can vary significantly between programs. Lack of generalizable standards for scholarly projects required of all trainees within ACGME-accredited residencies has led to a large range of quality and effort put forth to complete these projects. Our goal is to introduce a framework and propose a corresponding rubric for application to resident scholarship to quantify and qualify the components of scholarship to better measure resident scholarly output across the graduate medical education (GME) continuum. Methods: Eight experienced educators and members of the Society for Academic Emergency Medicine Education Committee were selected to explore the current scholarly project guidelines and propose a definition that can be universally applied to diverse training programs. Following a review of the current literature, the authors engaged in iterative, divergent, and convergent discussions via meetings and asynchronous dialogue to develop a framework and associated rubric. Results: The group proposes that emergency medicine (EM) resident scholarship should (1) involve a structured process, (2) generate outcomes, (3) be disseminated, and (4) be peer reviewed. These components of resident scholarly activity are achieved whether this is a single project encompassing all four domains, or multiple smaller projects that sum to the whole. To assist residency programs in assessing a given individual resident's achievement of the standards set forth, a rubric is proposed. Conclusion: Based on current literature and consensus, we propose a framework and rubric for tracking of resident scholarly project achievement in an effort to elevate and advance EM scholarship. Future work should explore the optimal application of this framework and define minimal scholarship goals for EM resident scholarship.

16.
Mar Environ Res ; 189: 106056, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37385084

RESUMEN

The West Antarctic Peninsula (WAP) is a hotspot of physical climate change, especially glacial retreat, particularly in its northern South Shetland Islands (SSI) region. Along coastlines, this process is opening up new ice-free areas, for colonization by a high biodiversity of flora and fauna. At Potter Cove, in the SSI (Isla 25 de Mayo/King George Island), Antarctica, colonization by macroalgae was studied in two newly ice-free areas, a low glacier influence area (LGI), and a high glacier influence area (HGI) differing in the presence of sediment run-off and light penetration, which are driven by levels of glacial influence. We installed artificial substrates (tiles) at 5 m depth to analyze benthic algal colonization and succession for four years (2010-2014). Photosynthetic active radiation (PAR, 400-700 nm), temperature, salinity, and turbidity were monitored at both sites in spring and summer. The turbidity and the light attenuation (Kd) were significantly lower at LGI than at HGI. All tiles were colonized by benthic algae, differing in species identity and successional patterns between areas, and with a significantly higher richness at LGI than HGI in the last year of the experiment. We scaled up a quadrat survey on the natural substrate to estimate benthic algal colonization in newly deglaciated areas across Potter Cove. Warming in recent decades has exposed much new habitat, with macroalgae making up an important part of colonist communities 'chasing' such glacier retreat. Our estimation of algal colonization in newly ice-free areas shows an expansion of ∼0.005-0.012 km2 with a carbon standing stock of ∼0.2-0.4 C tons, per year. Life moving into new space in such emerging fjords has the potential to be key for new carbon sinks and export. In sustained climate change scenarios, we expect that the processes of colonization and expansion of benthic assemblages will continue and generate significant transformations in Antarctic coastal ecosystems by increasing primary production, providing new structures, food and refuge to fauna, and capturing and storing more carbon.


Asunto(s)
Ecosistema , Algas Marinas , Carbono , Regiones Antárticas , Biodiversidad , Estuarios , Cubierta de Hielo
17.
PLoS One ; 18(5): e0266815, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256867

RESUMEN

In the context of established and emerging injection drug use epidemics, there is a need to prevent and avert injection drug use. We tested the hypothesis that an individual motivation and skills building counselling, adapted and enhanced from Hunt's Break the Cycle intervention targeting persons currently injecting drugs would lead to reduction in injection initiation-related behaviours among PWID in Tallinn, Estonia. For this quasi-experimental study, pre-post outcome measures included self-reported promoting behaviours (speaking positively about injecting to non-injectors, injecting in front of non-injectors, offering to give a first injection) and injection initiation behaviours (assisting with or giving a first injection) during the previous 6 months. Of 214 PWID recruited, 189 were retained (88.3%) for the follow-up at 6 months. The proportion of those who had injected in front of non-PWID significantly declined from 15.9% to 8.5%, and reporting assisting with 1st injection from 6.4% to 1.06%. Of the current injectors retained in the study, 17.5% reported not injecting drugs at the follow up. The intervention adapted for the use in the setting of high prevalence of HIV and relatively low prevalence of injection assisting, tested proved to be effective and safe.


Asunto(s)
Consumidores de Drogas , Infecciones por VIH , Abuso de Sustancias por Vía Intravenosa , Humanos , Estonia/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Abuso de Sustancias por Vía Intravenosa/prevención & control , Asunción de Riesgos , Infecciones por VIH/epidemiología
18.
J Biomech ; 150: 111490, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36878113

RESUMEN

Pelvis and lumbar spine fractures occur in falls, motor vehicle crashes, and military combat events. They are attributed to vertical impact from the pelvis to the spine. Although whole-body cadavers were exposed to this vector and injuries were reported, spinal loads were not determined. While previous studies determined injury metrics such as peak forces using isolated pelvis or spine models, they were not conducted using the combined pelvis-spine columns, thereby not accounting for the interaction between the two body regions. Earlier studies did not develop response corridors. The study objectives were to develop temporal corridors of loads at the pelvis and spine and assess clinical fracture patterns using a human cadaver model. Vertical impact loads were delivered at the pelvic end to twelve unembalmed intact pelvis-spine complexes, and pelvis forces and spinal loads (axial, shear and resultant and bending moments) were obtained. Injuries were classified using clinical assessments from post-test computed tomography scans. Spinal injuries were stable in eight and unstable in four specimens. Pelvis injuries included ring fractures in six and unilateral pelvis in three, sacrum fractures in ten, and two specimens did not sustain any injuries to the pelvis or sacrum complex. Data were grouped based on time to peak velocity, and ± one standard deviation corridors about the mean of the biomechanical metrics were developed. Time-history corridors of loads at the pelvis and spine, hitherto not reported in any study, are valuable to assess the biofidelity of anthropomorphic test devices and assist validating finite element models.


Asunto(s)
Traumatismos por Explosión , Fracturas de la Columna Vertebral , Traumatismos Vertebrales , Humanos , Vértebras Lumbares , Explosiones , Pelvis , Cadáver , Fenómenos Biomecánicos/fisiología
19.
Nature ; 615(7954): 817-822, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36746190

RESUMEN

Quantum computation features known examples of hardware acceleration for certain problems, but is challenging to realize because of its susceptibility to small errors from noise or imperfect control. The principles of fault tolerance may enable computational acceleration with imperfect hardware, but they place strict requirements on the character and correlation of errors1. For many qubit technologies2-21, some challenges to achieving fault tolerance can be traced to correlated errors arising from the need to control qubits by injecting microwave energy matching qubit resonances. Here we demonstrate an alternative approach to quantum computation that uses energy-degenerate encoded qubit states controlled by nearest-neighbour contact interactions that partially swap the spin states of electrons with those of their neighbours. Calibrated sequences of such partial swaps, implemented using only voltage pulses, allow universal quantum control while bypassing microwave-associated correlated error sources1,22-28. We use an array of six 28Si/SiGe quantum dots, built using a platform that is capable of extending in two dimensions following processes used in conventional microelectronics29. We quantify the operational fidelity of universal control of two encoded qubits using interleaved randomized benchmarking30, finding a fidelity of 96.3% ± 0.7% for encoded controlled NOT operations and 99.3% ± 0.5% for encoded SWAP. The quantum coherence offered by enriched silicon5-9,16,18,20,22,27,29,31-37, the all-electrical and low-crosstalk-control of partial swap operations1,22-28 and the configurable insensitivity of our encoding to certain error sources28,33,34,38 all combine to offer a strong pathway towards scalable fault tolerance and computational advantage.

20.
J Neuroimmune Pharmacol ; 18(1-2): 100-111, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36380156

RESUMEN

Trace amine-associated receptor 1 (TAAR1) is an established neuroregulatory G protein-coupled receptor with recent studies suggesting additional functions related to immunomodulation. Our lab has previously investigated TAAR1 expression within cells of the innate immune system and herein we aim to further elucidate TAAR1 function in both peripherally-derived and CNS-resident macrophages. The selective TAAR1 agonist RO5256390 was used in combination with common damage associated molecular patterns (ATP and ADP) to observe the effect of TAAR1 agonism on modulating cytokine secretion and metabolic profiles. In mouse bone-marrow derived macrophages, TAAR1 agonism inhibited TNF secretion following ATP stimulation, which appeared to be downstream of an associated pro-inflammatory shift in metabolic profile and transcriptional regulation of TNF synthesis. In contrast, TAAR1 agonism had no effect on ADP-induced TNF and IL-6 secretion in mouse microglia in either the presence or absence of astrocytes. In summary, we report a novel interaction between TAAR1 and purinergic signaling in peripherally-derived, but not CNS-resident, macrophages. These findings provide the first evidence of trace aminergic and purinergic crosstalk, and support the potential for TAAR1 as a novel therapeutic target in inflammatory disorders.


Asunto(s)
Macrófagos , Receptores Acoplados a Proteínas G , Ratones , Animales , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Macrófagos/metabolismo , Transducción de Señal , Adenosina Trifosfato/metabolismo
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