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1.
Proc Natl Acad Sci U S A ; 119(32): e2206345119, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35914152

RESUMEN

Methane (CH4) mole fractions from the large semiseasonal Llanos de Moxos wetlands (∼70,000 km2) in northern Bolivia were measured by aircraft flights and ground sampling during early March 2019 (late wet season). Daily fluxes of CH4 determined from the measurements using box models and inverse modeling were between 168 (± 50) and 456 (± 145) mg CH4⋅m-2⋅d-1 for the areas overflown, very high compared with those of previous Amazon basin studies. If the seasonality of the CH4 emissions is comparable to other parts of the Amazon Basin, the region could contribute as much as 8% of annual Amazonian CH4 emissions.


Asunto(s)
Gases de Efecto Invernadero , Humedales , Bolivia , Dióxido de Carbono/análisis , Gases de Efecto Invernadero/análisis , Metano/análisis , Estaciones del Año
2.
MMWR Morb Mortal Wkly Rep ; 73(24): 546-550, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900699

RESUMEN

Tecovirimat is the first-line antiviral treatment recommended for severe mpox or for persons with mpox who are at risk for severe disease; tecovirimat is available in the United States under an expanded access investigational new drug (IND) protocol. During the 2022-2023 mpox outbreak, local U.S. health jurisdictions facilitated access to tecovirimat. In June 2022, Los Angeles County (LAC) rapidly developed strategies for tecovirimat distribution using existing medical countermeasure distribution networks established by the Public Health Emergency Preparedness Program and the Hospital Preparedness Program, creating a hub and spoke distribution network consisting of 44 hub facilities serving 456 satellite sites across LAC. IND patient intake forms were analyzed to describe mpox patients treated with tecovirimat. Tecovirimat treatment data were matched with case surveillance data to calculate time from specimen collection to patients receiving tecovirimat. Among 2,281 patients with mpox in LAC, 735 (32%) received tecovirimat during June 2022-January 2023. Among treated patients, approximately two thirds (508; 69%) received treatment through community clinics and pharmacies. The median interval from specimen collection to treatment was 2 days (IQR = 0-5 days). Local data collection and analysis helped to minimize gaps in treatment access and facilitated network performance monitoring. During public health emergencies, medical countermeasures can be rapidly deployed across a large jurisdiction using existing distribution networks, including clinics and pharmacies.


Asunto(s)
Antivirales , Brotes de Enfermedades , Mpox , Humanos , Brotes de Enfermedades/prevención & control , Los Angeles/epidemiología , Persona de Mediana Edad , Adulto , Adolescente , Femenino , Masculino , Adulto Joven , Anciano , Antivirales/uso terapéutico , Niño , Mpox/epidemiología , Preescolar , Lactante , Pirrolidinas , Benzamidas/uso terapéutico , Anciano de 80 o más Años , Ftalimidas
3.
Environ Res ; 262(Pt 1): 119830, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39181299

RESUMEN

BACKGROUND: Dengue fever is an arboviral disease caused by the dengue virus (DENV). Its geographical distribution and health burden have been steadily increasing through tropical and subtropical climates in recent decades. METHODS: We developed a temperature- and precipitation-dependent mechanistic model for the global risk of dengue fever outbreaks using the basic reproduction number (R0) as the metric of disease transmission risk. We used our model to evaluate the global risk of dengue outbreaks from 1950 to 2020 and to investigate the impact of annual seasons and El Niño events. RESULTS: We showed that the global annual risk of dengue outbreaks has steadily increased during the last four decades. Highest R0 values were observed in South America, Southeast Asia, and the Equatorial region of Africa year-round with large seasonal variations occurring in other regions. El Niño was shown to be positively correlated with the global risk of dengue outbreaks with a correlation of 0.52. However, the impact of El Niño on dengue R0 was shown to vary across geographical regions and between El Niño events. CONCLUSIONS: Strong El Niño events may increase the risk of dengue outbreaks across the globe. The onset of these events may trigger a surge of control efforts to minimize risk of dengue outbreaks.

4.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34282013

RESUMEN

Seismic surveys are used to locate oil and gas reserves below the seabed and can be a major source of noise in marine environments. Their effects on commercial fisheries are a subject of debate, with experimental studies often producing results that are difficult to interpret. We overcame these issues in a large-scale experiment that quantified the impacts of exposure to a commercial seismic source on an assemblage of tropical demersal fishes targeted by commercial fisheries on the North West Shelf of Western Australia. We show that there were no short-term (days) or long-term (months) effects of exposure on the composition, abundance, size structure, behavior, or movement of this fauna. These multiple lines of evidence suggest that seismic surveys have little impact on demersal fishes in this environment.


Asunto(s)
Acústica/instrumentación , Ecosistema , Explotaciones Pesqueras/estadística & datos numéricos , Peces/crecimiento & desarrollo , Dinámica Poblacional , Animales , Monitoreo del Ambiente , Tecnología de Sensores Remotos , Australia Occidental
5.
Emerg Infect Dis ; 29(6): 1109-1116, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37095135

RESUMEN

In Los Angeles County, California, USA, public health surveillance identified 118 mpox cases among persons experiencing homelessness (PEH) during July-September 2022. Age and sex were similar for mpox case-patients among PEH and in the general population. Seventy-one (60%) PEH mpox case-patients were living with HIV, 35 (49%) of them virally suppressed. Hospitalization was required for 21% of case-patients because of severe disease. Sexual contact was likely the primary mode of transmission; 84% of patients reported sexual contact <3 weeks before symptom onset. PEH case-patients lived in shelters, encampments, cars, or on the street, or stayed briefly with friends or family (couch surfed). Some case-patients stayed at multiple locations during the 3-week incubation period. Public health follow-up and contact tracing detected no secondary mpox cases among PEH in congregate shelters or encampments. Equitable efforts should continue to identify, treat, and prevent mpox among PEH, who often experience severe disease.


Asunto(s)
Personas con Mala Vivienda , Mpox , Humanos , Los Angeles/epidemiología , Salud Pública , Trazado de Contacto
6.
Br J Surg ; 110(11): 1518-1526, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37697690

RESUMEN

BACKGROUND: This observational study, paired with National Health Service (NHS) workforce population data, examined gender differences in surgical workforce members' experiences with sexual misconduct (sexual harassment, sexual assault, rape) among colleagues in the past 5 years, and their views of the adequacy of accountable organizations in dealing with this issue. METHODS: This was a survey of UK surgical workforce members, recruited via surgical organizations. RESULTS: Some 1704 individuals participated, with 1434 (51.5 per cent women) eligible for primary unweighted analyses. Weighted analyses, grounded in NHS England surgical workforce population data, used 756 NHS England participants. Weighted and unweighted analyses showed that, compared with men, women were significantly more likely to report witnessing, and be a target of, sexual misconduct. Among women, 63.3 per cent reported being the target of sexual harassment versus 23.7 per cent of men (89.5 per cent witnessing versus 81.0 per cent of men). Additionally, 29.9 per cent of women had been sexually assaulted versus 6.9 per cent of men (35.9 per cent witnessing versus 17.1 per cent of men), with 10.9 per cent of women experiencing forced physical contact for career opportunities (a form of sexual assault) versus 0.7 per cent of men. Being raped by a colleague was reported by 0.8 per cent of women versus 0.1 per cent of men (1.9 per cent witnessing versus 0.6 per cent of men). Evaluations of organizations' adequacy in handling sexual misconduct were significantly lower among women than men, ranging from a low of 15.1 per cent for the General Medical Council to a high of 31.1 per cent for the Royal Colleges (men's evaluations: 48.6 and 60.2 per cent respectively). CONCLUSION: Sexual misconduct in the past 5 years has been experienced widely, with women affected disproportionately. Accountable organizations are not regarded as dealing adequately with this issue.


This research examined sexual misconduct occurring in surgery in the UK, so that more informed and targeted actions can be taken to make healthcare safer for staff and patients. A survey assessed individuals' experiences with being sexually harassed, sexually assaulted, and raped by work colleagues. Individuals were also asked whether they had seen this happen to others at work. Compared with men, women were much more likely to have seen sexual misconduct happening to others, and to have it happen to them. For example, most women (63.3 per cent) experienced being sexually harassed by colleagues, as did some men (23.7 per cent). Women also experienced being sexual assaulted by colleagues far more often than men (29.9 per cent of women, 6.9 per cent of men). These findings show that women and men in the surgical workforce are living different realities. For women, being around colleagues is more often going to mean witnessing, and being a target of, sexual misconduct. Individuals were also asked whether they thought healthcare-related organizations were handling issues of sexual misconduct adequately; most did not think they were. The General Medical Council (GMC) received the lowest evaluations. Only 15.1 per cent of women regarded the GMC as adequate in their handling of sexual misconduct. Men's evaluations were higher, although the GMC was still regarded as adequate by less than half of men (48.6 per cent). Evaluations of National Health Service Trusts were rated similarly low. Only 15.8 per cent of women evaluated them as adequate (44.9 per cent of men). The results of this study have implications for all stakeholders, including patients. Sexual misconduct was commonly experienced by respondents, representing a serious issue for the profession. There is a widespread lack of faith in the UK organizations responsible for dealing with this issue. Those organizations have a duty to protect the workforce, and to protect patients.


Asunto(s)
Violación , Delitos Sexuales , Acoso Sexual , Masculino , Humanos , Femenino , Medicina Estatal , Encuestas y Cuestionarios
7.
MMWR Morb Mortal Wkly Rep ; 72(20): 553-558, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37200229

RESUMEN

As of March 31, 2023, more than 30,000 monkeypox (mpox) cases had been reported in the United States in an outbreak that has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) and transgender persons (1). JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic) was approved by the Food and Drug Administration (FDA) in 2019 for the prevention of smallpox and mpox via subcutaneous injection as a 2-dose series (0.5 mL per dose, administered 4 weeks apart) (2). To expand vaccine access, an Emergency Use Authorization was issued by FDA on August 9, 2022, for dose-sparing intradermal injection of JYNNEOS as a 2-dose series (0.1 mL per dose, administered 4 weeks apart) (3). Vaccination was available to persons with known or presumed exposure to a person with mpox (postexposure prophylaxis [PEP]), as well as persons at increased risk for mpox or who might benefit from vaccination (preexposure mpox prophylaxis [PrEP]) (4). Because information on JYNNEOS vaccine effectiveness (VE) is limited, a matched case-control study was conducted in 12 U.S. jurisdictions,† including nine Emerging Infections Program sites and three Epidemiology and Laboratory Capacity sites,§ to evaluate VE against mpox among MSM and transgender adults aged 18-49 years. During August 19, 2022-March 31, 2023, a total of 309 case-patients were matched to 608 control patients. Adjusted VE was 75.2% (95% CI = 61.2% to 84.2%) for partial vaccination (1 dose) and 85.9% (95% CI = 73.8% to 92.4%) for full vaccination (2 doses). Adjusted VE for full vaccination by subcutaneous, intradermal, and heterologous routes of administration was 88.9% (95% CI = 56.0% to 97.2%), 80.3% (95% CI = 22.9% to 95.0%), and 86.9% (95% CI = 69.1% to 94.5%), respectively. Adjusted VE for full vaccination among immunocompromised participants was 70.2% (95% CI = -37.9% to 93.6%) and among immunocompetent participants was 87.8% (95% CI = 57.5% to 96.5%). JYNNEOS is effective at reducing the risk for mpox. Because duration of protection of 1 versus 2 doses remains unknown, persons at increased risk for mpox exposure should receive the 2-dose series as recommended by the Advisory Committee on Immunization Practices (ACIP),¶ regardless of administration route or immunocompromise status.


Asunto(s)
Mpox , Minorías Sexuales y de Género , Vacuna contra Viruela , Adulto , Masculino , Humanos , Estados Unidos/epidemiología , Homosexualidad Masculina , Estudios de Casos y Controles
8.
BMC Health Serv Res ; 23(1): 299, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36978068

RESUMEN

BACKGROUND: Stroke Early Supported Discharge (ESD) involves provision of responsive and intensive rehabilitation to stroke survivors at home and it is recommended as part of the stroke care pathway. Core components have been identified to guide the delivery of evidence-based ESD, however, service provision in England is of variable quality. The study sought to understand how and in what conditions the adoption of these components drives the delivery of responsive and intensive ESD services in real world settings. METHODS: This qualitative study was part of a wider multimethod realist evaluation project (WISE) conducted to inform large-scale ESD implementation. Overarching programme theories and related context-mechanism-outcome configurations were used as a framework to guide data collection and analysis. Six case study sites were purposively selected; interviews and focus groups with ESD staff members were conducted and analysed iteratively. RESULTS: We interviewed 117 ESD staff members including clinicians and service managers. Staff highlighted the role of certain core components including eligibility criteria, capacity, team composition and multidisciplinary team (MDT) coordination in achieving responsive and intensive ESD. Regardless of the geographical setting, adhering to evidence-based selection criteria, promoting an interdisciplinary skillset and supporting the role of rehabilitation assistants, allowed teams to manage capacity issues and maximise therapy time. Gaps in the stroke care pathway, however, meant that teams had to problem solve beyond their remit to cater for the complex needs of patients with severe disabilities. Adjusting MDT structures and processes was seen as key in addressing challenges posed by travel times and rural geography. CONCLUSIONS: Despite variations in the wider service model of operation and geographical location, the adoption of core components of ESD helped teams manage the pressures and deliver services that met evidence-based standards. Findings point to a well-recognised gap in service provision in England for stroke survivors who do not meet the ESD criteria and emphasise the need for a more integrated and comprehensive stroke service provision. Transferable lessons could be drawn to inform improvement interventions aimed at promoting evidence-based service delivery in different settings. TRIAL REGISTRATION: ISRCTN: 15,568,163, registration date: 26 October 2018.


Asunto(s)
Personas con Discapacidad , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Alta del Paciente , Accidente Cerebrovascular/terapia , Inglaterra
9.
J Infect Dis ; 225(3): 367-373, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34031692

RESUMEN

BACKGROUND: The prevalence of current or past coronavirus disease 2019 in skilled nursing facility (SNF) residents is unknown because of asymptomatic infection and constrained testing capacity early in the pandemic. We conducted a seroprevalence survey to determine a more comprehensive prevalence of past coronavirus disease 2019 in Los Angeles County SNF residents and staff members. METHODS: We recruited participants from 24 facilities; participants were requested to submit a nasopharyngeal swab sample for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) testing and a serum sample for detection of SARS-CoV-2 antibodies. All participants were cross-referenced with our surveillance database to identify persons with prior positive SARS-CoV-2 results. RESULTS: From 18 August to 24 September 2020, we enrolled 3305 participants (1340 residents and 1965 staff members). Among 856 residents providing serum samples, 362 (42%) had current or past SARS-CoV-2 infection. Of the 346 serology-positive residents, 199 (58%) did not have a documented prior positive SARS-CoV-2 PCR result. Among 1806 staff members providing serum, 454 (25%) had current or past SARS-CoV-2 infection. Of the 447 serology-positive staff members, 353 (79%) did not have a documented prior positive SARS-CoV-2 PCR result. CONCLUSIONS: Past testing practices and policies missed a substantial number of SARS-CoV-2 infections in SNF residents and staff members.


Asunto(s)
COVID-19/epidemiología , SARS-CoV-2 , Personal de Salud , Humanos , Los Angeles/epidemiología , SARS-CoV-2/aislamiento & purificación , Estudios Seroepidemiológicos , Instituciones de Cuidados Especializados de Enfermería
10.
Ann Surg ; 275(3): e568-e574, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32590540

RESUMEN

OBJECTIVE: A simulator to enable safe practice and assessment of ALND has been designed, and face, content and construct validity has been investigated. SUMMARY AND BACKGROUND DATA: The reduction in the number of ALNDs conducted has led to decreased resident exposure and confidence. METHODS: A cross-sectional multicenter observational study was carried out between July 2017 and August 2018. Following model development, 30 surgeons of varying experience (n = "experts," n = 11 "senior residents," and n = 10 "junior residents") were asked to perform a simulated ALND. Face and content validity questionnaires were administered immediately after ALND. All ALND procedures were retrospectively assessed by 2 attending breast surgeons, blinded to operator identity, using a video-based assessment tool, and an end product assessment tool. RESULTS: Statistically significant differences between groups were observed across all operative subphases on the axillary clearance assessment tool (P < 0.001). Significant differences between groups were observed for overall procedure quality (P < 0.05) and total number of lymph nodes harvested (P < 0.001). However, operator grade could not be distinguished across other end product variables such as axillary vein damage (P = 0.864) and long thoracic nerve injury (P = 0.094). Overall, participants indicated that the simulator has good anatomical (median score >7) and procedural realism (median score >7). CONCLUSIONS: Video-based analysis demonstrates construct validity for ALND assessment. Given reduced ALND exposure, this simulation is a useful adjunct for both technical skills training and formative Deanery or Faculty administered assessments.


Asunto(s)
Competencia Clínica , Escisión del Ganglio Linfático/normas , Axila , Estudios Transversales , Humanos , Estudios Retrospectivos
11.
MMWR Morb Mortal Wkly Rep ; 71(5): 177-181, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35113851

RESUMEN

COVID-19 vaccines are effective at preventing infection with SARS-CoV-2, the virus that causes COVID-19, as well as severe COVID-19-associated outcomes in real-world conditions (1,2). The risks for SARS-CoV-2 infection and COVID-19-associated hospitalization are lower among fully vaccinated than among unvaccinated persons; this reduction is even more pronounced among those who have received additional or booster doses (boosters) (3,4). Although the B.1.1.529 (Omicron) variant spreads more rapidly than did earlier SARS-CoV-2 variants, recent studies suggest that disease severity is lower for Omicron compared with that associated with the B.1.617.2 (Delta) variant; but the high volume of infections is straining the health care system more than did previous waves (5).*,† The Los Angeles County (LAC) Department of Public Health (LACDPH) used COVID-19 surveillance and California Immunization Registry 2 (CAIR2) data to describe age-adjusted 14-day cumulative incidence and hospitalization rates during November 7, 2021-January 8, 2022, by COVID-19 vaccination status and variant predominance. For the 14-day period ending December 11, 2021, the last week of Delta predominance, the incidence and hospitalization rates among unvaccinated persons were 12.3 and 83.0 times, respectively, those of fully vaccinated persons with a booster and 3.8 and 12.9 times, respectively, those of fully vaccinated persons without a booster. These rate ratios were lower during Omicron predominance (week ending January 8, 2022), with unvaccinated persons having infection and hospitalization rates 3.6 and 23.0 times, respectively, those of fully vaccinated persons with a booster and 2.0 and 5.3 times, respectively, those of fully vaccinated persons without a booster. In addition, during the entire analytic period, admission to intensive care units (ICUs), intubation for mechanical ventilation, and death were more likely to occur among unvaccinated persons than among fully vaccinated persons without or with a booster (p<0.001). Incidence and hospitalization rates were consistently highest for unvaccinated persons and lowest for fully vaccinated persons with a booster. Being up to date with COVID-19 vaccination is critical to protecting against SARS-CoV-2 infection and associated hospitalization.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/epidemiología , Hospitalización/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/prevención & control , Femenino , Humanos , Incidencia , Los Angeles/epidemiología , Masculino , Persona de Mediana Edad , Gravedad del Paciente , SARS-CoV-2/inmunología , Adulto Joven
12.
J Surg Res ; 278: 337-341, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35660303

RESUMEN

INTRODUCTION: Mount Sinai Hospital in New York introduced a laparoscopic surgery simulation center to a public hospital in Santiago, Dominican Republic to determine the feasibility of training programs in low-and-middle income countries (LMICs). METHODS: In August 2018, recruitment and preliminary data were collected at the Hospital Jose Maria Cabral y Báez in Santiago, Dominican Republic. The simulation room consists of three simulation stations. Residents were required to practice 1 h/wk guided by a general surgery postgraduate year 3 (PGY3) Mount Sinai resident. Number of hours practiced was self-reported and follow-up data was collected in June 2019. The study endpoints include times on three simulated laparoscopic tasks including peg-transfer, precision cutting, and intracorporeal knot tying. Wilcoxon-signed rank tests were used for statistical analysis. RESULTS: The partnership between hospitals allowed for successful integration into the Dominican general surgery training. Over 10 mo, residents averaged 25 h of practice (range: 8-35 h; SD 9.95 h). In total, 85% of the residents participated in the study (5 postgraduate year 1 [PGY1], 2 postgraduate year 2 [PGY2], and 4 postgraduate year 3 [PGY3]). Resident median simulation times significantly improved for precision cutting (3:49 min versus 2:09 min, P = 0.002) and intracorporeal knot tying (5:20 min versus 2:47 min, P = 0.037). There was neither significant difference in peg-transfer times nor performance between resident years (P = 0.12). CONCLUSIONS: This study demonstrates the successful integration of a laparoscopic simulation program into an LMIC surgical resident training program. With commitment from local institutions and external resources, establishing laparoscopic simulation centers are feasible and expandable, thereby allowing general surgery residents in other LMICs, the opportunity to improve their laparoscopic skills.


Asunto(s)
Cirugía General , Internado y Residencia , Laparoscopía , Entrenamiento Simulado , Competencia Clínica , República Dominicana , Cirugía General/educación , Humanos , Laparoscopía/educación
13.
Conserv Biol ; 36(2): e13807, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34312893

RESUMEN

Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.


Las pesquerías marinas de los ecosistemas costeros en muchas áreas del mundo históricamente han removido a individuos de gran tamaño, potencialmente perjudicando el funcionamiento ambiental y la sostenibilidad a largo plazo de las poblaciones de peces. Los reportes sobre los indicadores basados en el tamaño que se vinculan con la estructura de la red alimenticia pueden contribuir al manejo basado en el ecosistema, aunque la aplicación de estos indicadores a grandes (inter-ecosistemas) escalas geográficas ha estado limitada a datos de captura dependientes de las pesquerías o métodos basados en el buceo restringidos a aguas someras (<20 m), lo cual puede representar erróneamente la abundancia de peces de gran tamaño capturados para la pesca. Obtuvimos los datos de la estructura del tamaño corporal de 82 teleósteos marinos demersales focalizados por razones recreativas o comerciales tomados de 2,904 despliegues de video estéreo subacuático remoto con cebo (stereo-BRUV, en inglés). El muestreo se realizó hasta los 50 metros de profundidad y abarcó aproximadamente 10,000 km del talud continental de Australia. El relieve marino, la profundidad del agua y la gravedad humana (es decir, un indicador de los impactos humanos) fueron los pronosticadores más sólidos de la probabilidad de incidencia de los peces de gran tamaño y de la abundancia de peces por encima del tamaño legal mínimo de captura. Las reservas marinas de protección total tienen un efecto positivo sobre la abundancia de los peces que están por encima del tamaño legal, aunque el efecto varió según el grupo de especies. Como contraste, los peces de tamaño sublegal fueron pronosticados de mejor manera usando gradientes de la temperatura de la superficie marina (media y varianza). En las áreas con un impacto humano reducido, los peces de gran tamaño corporal tenían hasta tres veces mayor probabilidad de aparecer y los peces de tamaño legal eran aproximadamente cinco veces más abundantes. Para los grupos de especies conspicuas con afinidades contrastantes de hábitat, ambiente y biogeografía, la abundancia de peces de tamaño legal normalmente declinó conforme aumentó el impacto humano. Nuestros análisis cuantitativos a gran escala resaltan la importancia conjunta que tienen la complejidad marina, las regiones con una huella humana reducida y las reservas marinas de protección total para la protección de los peces de gran tamaño corporal en una extensa gama de especies y configuraciones ecosistémicas. Efectos de la Huella Humana y los Factores Biofísicos sobre la Estructura del Tamaño Corporal de Especies Marinas Capturadas para la Pesca.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Australia , Tamaño Corporal , Explotaciones Pesqueras , Peces , Humanos
14.
Philos Trans A Math Phys Eng Sci ; 380(2215): 20210108, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34865528

RESUMEN

Removing methane from the air is possible, but do the costs outweigh the benefits? This note explores the question of whether removing methane from the atmosphere is justifiable. Destruction of methane by oxidation to CO2 eliminates 97% of the warming impact on a 100-yr time scale. Methane can be oxidized by a variety of methods including thermal or ultraviolet photocatalysis and various processes of physical, chemical or biological oxidizers. Each removal method has energy costs (with the risk of causing embedded CO2 emission that cancel the global warming gain), but in specific circumstances, including settings where air with high methane is habitually present, removal may be competitive with direct efforts to cut fugitive methane leaks. In all cases however, great care must be taken to ensure that the destruction has a net positive impact on the total global warming, and that the resources required would not be better used for stopping the methane from being emitted. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.


Asunto(s)
Metano , Oxidación-Reducción
15.
Philos Trans A Math Phys Eng Sci ; 380(2215): 20210192, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34865529

RESUMEN

Arctic wetlands and surrounding ecosystems are both a significant source of methane (CH4) and a sink of carbon dioxide (CO2) during summer months. However, precise quantification of this regional CH4 source and CO2 sink remains poorly characterized. A research flight using the UK Facility for Airborne Atmospheric Measurement was conducted in July 2019 over an area (approx. 78 000 km2) of mixed peatland and forest in northern Sweden and Finland. Area-averaged fluxes of CH4 and carbon dioxide were calculated using an aircraft mass balance approach. Net CH4 fluxes normalized to wetland area ranged between 5.93 ± 1.87 mg m-2 h-1 and 4.44 ± 0.64 mg m-2 h-1 (largest to smallest) over the region with a meridional gradient across three discrete areas enclosed by the flight survey. From largest to smallest, net CO2 sinks ranged between -513 ± 74 mg m-2 h-1 and -284 ± 89 mg m-2 h-1 and result from net uptake of CO2 by vegetation and soils in the biosphere. A clear gradient of decreasing bulk and area-averaged CH4 flux was identified from north to south across the study region, correlated with decreasing peat bog land area from north to south identified from CORINE land cover classifications. While N2O mole fraction was measured, no discernible gradient was measured over the flight track, but a minimum flux threshold using this mass balance method was calculated. Bulk (total area) CH4 fluxes determined via mass balance were compared with area-weighted upscaled chamber fluxes from the same study area and were found to agree well within measurement uncertainty. The mass balance CH4 fluxes were found to be significantly higher than the CH4 fluxes reported by many land-surface process models compiled as part of the Global Carbon Project. There was high variability in both flux distribution and magnitude between the individual models. This further supports previous studies that suggest that land-surface models are currently ill-equipped to accurately capture carbon fluxes inthe region. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.


Asunto(s)
Metano , Humedales , Dióxido de Carbono , Ecosistema , Estaciones del Año
16.
Philos Trans A Math Phys Eng Sci ; 380(2215): 20200449, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34865534

RESUMEN

The atmospheric methane (CH4) burden is rising sharply, but the causes are still not well understood. One factor of uncertainty is the importance of tropical CH4 emissions into the global mix. Isotopic signatures of major sources remain poorly constrained, despite their usefulness in constraining the global methane budget. Here, a collection of new δ13CCH4 signatures is presented for a range of tropical wetlands and rice fields determined from air samples collected during campaigns from 2016 to 2020. Long-term monitoring of δ13CCH4 in ambient air has been conducted at the Chacaltaya observatory, Bolivia and Southern Botswana. Both long-term records are dominated by biogenic CH4 sources, with isotopic signatures expected from wetland sources. From the longer-term Bolivian record, a seasonal isotopic shift is observed corresponding to wetland extent suggesting that there is input of relatively isotopically light CH4 to the atmosphere during periods of reduced wetland extent. This new data expands the geographical extent and range of measurements of tropical wetland and rice δ13CCH4 sources and hints at significant seasonal variation in tropical wetland δ13CCH4 signatures which may be important to capture in future global and regional models. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.


Asunto(s)
Oryza , Humedales , Atmósfera , Metano , Estaciones del Año
17.
Philos Trans A Math Phys Eng Sci ; 380(2215): 20210112, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34865533

RESUMEN

We report methane isotopologue data from aircraft and ground measurements in Africa and South America. Aircraft campaigns sampled strong methane fluxes over tropical papyrus wetlands in the Nile, Congo and Zambezi basins, herbaceous wetlands in Bolivian southern Amazonia, and over fires in African woodland, cropland and savannah grassland. Measured methane δ13CCH4 isotopic signatures were in the range -55 to -49‰ for emissions from equatorial Nile wetlands and agricultural areas, but widely -60 ± 1‰ from Upper Congo and Zambezi wetlands. Very similar δ13CCH4 signatures were measured over the Amazonian wetlands of NE Bolivia (around -59‰) and the overall δ13CCH4 signature from outer tropical wetlands in the southern Upper Congo and Upper Amazon drainage plotted together was -59 ± 2‰. These results were more negative than expected. For African cattle, δ13CCH4 values were around -60 to -50‰. Isotopic ratios in methane emitted by tropical fires depended on the C3 : C4 ratio of the biomass fuel. In smoke from tropical C3 dry forest fires in Senegal, δ13CCH4 values were around -28‰. By contrast, African C4 tropical grass fire δ13CCH4 values were -16 to -12‰. Methane from urban landfills in Zambia and Zimbabwe, which have frequent waste fires, had δ13CCH4 around -37 to -36‰. These new isotopic values help improve isotopic constraints on global methane budget models because atmospheric δ13CCH4 values predicted by global atmospheric models are highly sensitive to the δ13CCH4 isotopic signatures applied to tropical wetland emissions. Field and aircraft campaigns also observed widespread regional smoke pollution over Africa, in both the wet and dry seasons, and large urban pollution plumes. The work highlights the need to understand tropical greenhouse gas emissions in order to meet the goals of the UNFCCC Paris Agreement, and to help reduce air pollution over wide regions of Africa. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.


Asunto(s)
Contaminación del Aire , Humedales , Agricultura , Animales , Bovinos , Metano/análisis , Estaciones del Año
18.
Proc Natl Acad Sci U S A ; 116(19): 9370-9379, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31004057

RESUMEN

We report a complete 3D structural model of typical epithelial primary cilia based on structural maps of full-length primary cilia obtained by serial section electron tomography. Our data demonstrate the architecture of primary cilia differs extensively from the commonly acknowledged 9+0 paradigm. The axoneme structure is relatively stable but gradually evolves from base to tip with a decreasing number of microtubule complexes (MtCs) and a reducing diameter. The axonemal MtCs are cross-linked by previously unrecognized fibrous protein networks. Such an architecture explains why primary cilia can elastically withstand liquid flow for mechanosensing. The nine axonemal MtCs in a cilium are found to differ significantly in length indicating intraflagellar transport processes in primary cilia may be more complicated than that reported for motile cilia. The 3D maps of microtubule doublet-singlet transitions generally display longitudinal gaps at the inner junction between the A- and B-tubules, which indicates the inner junction protein is a major player in doublet-singlet transitions. In addition, vesicles releasing from kidney primary cilia were observed in the structural maps, supporting that ciliary vesicles budding may serve as ectosomes for cell-cell communication.


Asunto(s)
Cilios/ultraestructura , Células Epiteliales/ultraestructura , Animales , Axonema/metabolismo , Axonema/ultraestructura , Línea Celular , Cilios/metabolismo , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/ultraestructura , Perros , Tomografía con Microscopio Electrónico , Células Epiteliales/metabolismo , Imagenología Tridimensional , Microtúbulos/metabolismo
19.
Glob Chang Biol ; 27(15): 3432-3447, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34015863

RESUMEN

Marine reserves are a key tool for the conservation of marine biodiversity, yet only ~2.5% of the world's oceans are protected. The integration of marine reserves into connected networks representing all habitats has been encouraged by international agreements, yet the benefits of this design has not been tested empirically. Australia has one of the largest systems of marine reserves, providing a rare opportunity to assess how connectivity influences conservation success. An Australia-wide dataset was collected using baited remote underwater video systems deployed across a depth range from 0 to 100 m to assess the effectiveness of marine reserves for protecting teleosts subject to commercial and recreational fishing. A meta-analytical comparison of 73 fished species within 91 marine reserves found that, on average, marine reserves had 28% greater abundance and 53% greater biomass of fished species compared to adjacent areas open to fishing. However, benefits of protection were not observed across all reserves (heterogeneity), so full subsets generalized additive modelling was used to consider factors that influence marine reserve effectiveness, including distance-based and ecological metrics of connectivity among reserves. Our results suggest that increased connectivity and depth improve the aforementioned marine reserve benefits and that these factors should be considered to optimize such benefits over time. We provide important guidance on factors to consider when implementing marine reserves for the purpose of increasing the abundance and size of fished species, given the expected increase in coverage globally. We show that marine reserves that are highly protected (no-take) and designed to optimize connectivity, size and depth range can provide an effective conservation strategy for fished species in temperate and tropical waters within an overarching marine biodiversity conservation framework.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Australia , Ecosistema , Explotaciones Pesqueras , Peces , Océanos y Mares
20.
MMWR Morb Mortal Wkly Rep ; 70(35): 1220-1222, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34473679

RESUMEN

In-person instruction during the COVID-19 pandemic concerns educators, unions, parents, students, and public health officials as they plan to create a safe and supportive learning environment for children and adolescents (1). Los Angeles County (LAC), the nation's largest county, has an estimated population of 10 million, including 1.7 million children and adolescents aged 5-17 years (2). LAC school districts moved to remote learning for some or all students in transitional kindergarten* through grade 12 (TK-12) schools during the 2020-21 school year (3). Schools that provided in-person instruction were required by LAC Health Officer orders to implement prevention measures such as symptom screening, masking, physical distancing, cohorting, and contact tracing (4). This analysis compares COVID-19 case rates in TK-12 schools among students and staff members who attended school in person with LAC case rates during September 2020-March 2021.


Asunto(s)
COVID-19/epidemiología , Características de la Residencia/estadística & datos numéricos , Instituciones Académicas/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Los Angeles/epidemiología , Masculino , Persona de Mediana Edad , Adulto Joven
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