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1.
Ecol Appl ; 27(6): 1815-1826, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28464529

RESUMEN

Patterns of bee abundance and diversity across different spatial scales have received thorough research consideration. However, the impact of short- and long-term temporal resource availability on biodiversity has been less explored. This is highly relevant in tropical agricultural systems for pollinators, as many foraging periods of pollinators extend beyond flowering of any single crop species. In this study, we sought to understand how bee communities in tropical agroecosystems changed between seasons, and if short- and long-term floral resource availability influenced their diversity and abundance. We used a threshold analysis approach in order to explore this relationship at two time scales. This study took place in a region dominated by coffee agroecosystems in Southern Mexico. This was an ideal system because the landscape offers a range of coffee management regimes that maintain heterogeneity in floral resource availability spatially and temporally. We found that the bee community varies significantly between seasons. There were higher abundances of native social, solitary and managed honey bees during the dry season when coffee flowers. Additionally, we found that floral resources from groundcover, but not trees, were associated with bee abundance. Further, the temporal scale of the availability of these resources is important, whereby short-term floral resource availability appears particularly important in maintaining high bee abundance at sites with lower seasonal complementarity. We argue that in addition to spatial resource heterogeneity, temporal resource heterogeneity is critical in explaining bee community patterns, and should thus be considered to promote pollinator conservation.


Asunto(s)
Abejas/fisiología , Conservación de los Recursos Naturales , Producción de Cultivos , Flores , Polinización , Animales , Biodiversidad , Coffea/crecimiento & desarrollo , México , Densidad de Población
2.
J Insect Sci ; 17(2)2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28355478

RESUMEN

The intensification of agriculture drives many ecological and environmental consequences including impacts on crop pest populations and communities. These changes are manifested at multiple scales including small-scale management practices and changes to the composition of land-use types in the surrounding landscape. In this study, we sought to examine the influence of local and landscape-scale agricultural factors on a leafhopper herbivore community in Mexican coffee plantations. We sampled leafhopper (Hemiptera: Cicadellidae) diversity in 38 sites from 9 coffee plantations of the Soconusco region of Chiapas, Mexico. While local management factors such as coffee density, branches per coffee bush, tree species, and density were not important in explaining leafhopper abundance and richness, shade management at the landscape level and elevation significantly affected leafhoppers. Specifically, the percentage of low-shade coffee in the landscape (1,000-m radius surrounding sites) increased total leafhopper abundance. In addition, Shannon's diversity of leafhoppers was increased with coffee density. Our results show that abundance and diversity of leafhoppers are greater in simplified landscapes, thereby suggesting that these landscapes will have higher pest pressure and may be more at-risk for diseases vectored by these species in an economically important crop.


Asunto(s)
Agricultura/métodos , Café/parasitología , Hemípteros/fisiología , Altitud , Animales , Biodiversidad , Ecosistema , México , Densidad de Población
3.
Proc Biol Sci ; 281(1791): 20141358, 2014 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-25100703

RESUMEN

Biodiversity loss--one of the most prominent forms of modern environmental change--has been heavily driven by terrestrial habitat loss and, in particular, the spread and intensification of agriculture. Expanding agricultural land-use has led to the search for strong conservation strategies, with some suggesting that biodiversity conservation in agriculture is best maximized by reducing local management intensity, such as fertilizer and pesticide application. Others highlight the importance of landscape-level approaches that incorporate natural or semi-natural areas in landscapes surrounding farms. Here, we show that both of these practices are valuable to the conservation of biodiversity, and that either local or landscape factors can be most crucial to conservation planning depending on which types of organisms one wishes to save. We performed a quantitative review of 266 observations taken from 31 studies that compared the impacts of localized (within farm) management strategies and landscape complexity (around farms) on the richness and abundance of plant, invertebrate and vertebrate species in agro-ecosystems. While both factors significantly impacted species richness, the richness of sessile plants increased with less-intensive local management, but did not significantly respond to landscape complexity. By contrast, the richness of mobile vertebrates increased with landscape complexity, but did not significantly increase with less-intensive local management. Invertebrate richness and abundance responded to both factors. Our analyses point to clear differences in how various groups of organisms respond to differing scales of management, and suggest that preservation of multiple taxonomic groups will require multiple scales of conservation.


Asunto(s)
Agricultura , Biodiversidad , Conservación de los Recursos Naturales/métodos , Animales , Invertebrados/fisiología , Fenómenos Fisiológicos de las Plantas , Vertebrados/fisiología
4.
PLoS One ; 19(6): e0305367, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38870154

RESUMEN

Despite the importance of a diversity of backgrounds and perspectives in biological research, women, racial and ethnic minorities, and students from non-traditional academic backgrounds remain underrepresented in the composition of university faculty. Through a study on doctoral students at a research-intensive university, we pinpoint advising from faculty as a critical component of graduate student experiences and productivity. Graduate students from minority backgrounds reported lower levels of support from their advisors and research groups. However, working with an advisor from a similar demographic background substantially improved productivity and well-being of these students. Several other aspects of mentoring practices positively predicted student success and belonging, including frequent one-on-one meetings, empathetic and constructive feedback, and relationships with other peer or faculty mentors. Our study highlights the need to renovate graduate education with a focus on retention-not just recruitment-to best prepare students for success in scientific careers.


Asunto(s)
Educación de Postgrado , Tutoría , Estudiantes , Humanos , Femenino , Estudiantes/psicología , Masculino , Disciplinas de las Ciencias Biológicas/educación , Mentores , Adulto , Universidades , Grupos Minoritarios , Estudios de Cohortes , Docentes/psicología
5.
Front Immunol ; 15: 1368118, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756770

RESUMEN

Frequencies and phenotypes of immune cells differ between neonates and adults in association with age-specific immune responses. Lymph nodes (LN) are critical tissue sites to quantify and define these differences. Advances in flow cytometry have enabled more multifaceted measurements of complex immune responses. Tissue processing can affect the immune cells under investigation that influence key findings. To understand the impact on immune cells in the LN after processing for single-cell suspension, we compared three dissociation protocols: enzymatic digestion, mechanical dissociation with DNase I treatment, and mechanical dissociation with density gradient separation. We analyzed cell yields, viability, phenotypic and maturation markers of immune cells from the lung-draining LN of neonatal and adult mice two days after intranasal respiratory syncytial virus (RSV) infection. While viability was consistent across age groups, the protocols influenced the yield of subsets defined by important phenotypic and activation markers. Moreover, enzymatic digestion did not show higher overall yields of conventional dendritic cells and macrophages from the LN. Together, our findings show that the three dissociation protocols have similar impacts on the number and viability of cells isolated from the neonatal and adult LN. However, enzymatic digestion impacts the mean fluorescence intensity of key lineage and activation markers that may influence experimental findings.


Asunto(s)
Animales Recién Nacidos , Ganglios Linfáticos , Linfocitos , Células Mieloides , Fenotipo , Infecciones por Virus Sincitial Respiratorio , Animales , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/citología , Ratones , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/virología , Linfocitos/inmunología , Linfocitos/metabolismo , Células Mieloides/inmunología , Separación Celular/métodos , Citometría de Flujo/métodos , Inmunofenotipificación , Femenino , Ratones Endogámicos C57BL , Células Dendríticas/inmunología , Células Dendríticas/metabolismo
6.
Ecology ; 101(4): e02944, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31828784

RESUMEN

Mexico is one of the most biodiverse countries in the world, with an important proportion of endemism mainly because of the convergence of the Nearctic and Neotropical biogeographic regions, which generate great diversity and species turnover at different spatial scales. However, most of our knowledge of the Mexican ant biota is limited to a few well-studied taxa, and we lack a comprehensive synthesis of ant biodiversity information. For instance, most of the knowledge available in the literature on Mexican ant fauna refers only to species lists by states, or is focused on only a few regions of the country, which prevents the study of several basic and applied aspects of ants, from diversity and distribution to conservation. Our aims in this data paper are therefore (1) to compile all the information available regarding ants across the Mexican territory, and (2) to identify major patterns in the gathered data set and geographic gaps in order to direct future sampling efforts. All records were obtained from raw data, including both unpublished and published information. After exhaustive filtering and updating information and synonyms, we compiled a total of 21,731 records for 887 ant species distributed throughout Mexico from 1894 to 2018. These records were concentrated mainly in the states of Chiapas (n = 6,902, 32.76%) and Veracruz de Ignacio de la Llave (n = 4,329, 19.92%), which together comprise half the records. The subfamily with the highest number of records was Myrmicinae (n = 10,458 records, 48.12%), followed by Formicinae (n = 3,284, 15.11%) and Ponerinae (n = 1,914, 8.8%). Most ant records were collected in the Neotropical region of the country (n = 12,646, 58.19%), followed by the Mexican transition zone (n = 5,237, 24.09%) and the Nearctic region (n = 3,848, 17.72%). Native species comprised 95.46% of the records (n = 20,745). To the best of our knowledge, this is the most complete data set available to date in the literature for the country. We hope that this compilation will encourage researchers to explore different aspects of the population and community research of ants at different spatial scales, and to aid in the establishment of conservation policies and actions. There are no copyright restrictions. Please cite this data paper when using its data for publications or teaching events.


Asunto(s)
Hormigas , Animales , Biodiversidad , Biota , Incidencia , México
7.
Lancet Infect Dis ; 18(9): 992-1003, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30153934

RESUMEN

BACKGROUND: Viral meningitis is increasingly recognised, but little is known about the frequency with which it occurs, or the causes and outcomes in the UK. We aimed to determine the incidence, causes, and sequelae in UK adults to improve the management of patients and assist in health service planning. METHODS: We did a multicentre prospective observational cohort study of adults with suspected meningitis at 42 hospitals across England. Nested within this study, in the National Health Service (NHS) northwest region (now part of NHS England North), was an epidemiological study. Patients were eligible if they were aged 16 years or older, had clinically suspected meningitis, and either underwent a lumbar puncture or, if lumbar puncture was contraindicated, had clinically suspected meningitis and an appropriate pathogen identified either in blood culture or on blood PCR. Individuals with ventricular devices were excluded. We calculated the incidence of viral meningitis using data from patients from the northwest region only and used these data to estimate the population-standardised number of cases in the UK. Patients self-reported quality-of-life and neuropsychological outcomes, using the EuroQol EQ-5D-3L, the 36-Item Short Form Health Survey (SF-36), and the Aldenkamp and Baker neuropsychological assessment schedule, for 1 year after admission. FINDINGS: 1126 patients were enrolled between Sept 30, 2011, and Sept 30, 2014. 638 (57%) patients had meningitis: 231 (36%) cases were viral, 99 (16%) were bacterial, and 267 (42%) had an unknown cause. 41 (6%) cases had other causes. The estimated annual incidence of viral meningitis was 2·73 per 100 000 and that of bacterial meningitis was 1·24 per 100 000. The median length of hospital stay for patients with viral meningitis was 4 days (IQR 3-7), increasing to 9 days (6-12) in those treated with antivirals. Earlier lumbar puncture resulted in more patients having a specific cause identified than did those who had a delayed lumbar puncture. Compared with the age-matched UK population, patients with viral meningitis had a mean loss of 0·2 quality-adjusted life-years (SD 0·04) in that first year. INTERPRETATION: Viruses are the most commonly identified cause of meningitis in UK adults, and lead to substantial long-term morbidity. Delays in getting a lumbar puncture and unnecessary treatment with antivirals were associated with longer hospital stays. Rapid diagnostics and rationalising treatments might reduce the burden of meningitis on health services. FUNDING: Meningitis Research Foundation and UK National Institute for Health Research.


Asunto(s)
Meningitis Viral/diagnóstico , Meningitis Viral/tratamiento farmacológico , Vigilancia de la Población , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Meningitis Viral/epidemiología , Persona de Mediana Edad , Estudios Prospectivos , Reino Unido/epidemiología
8.
J Geriatr Phys Ther ; 35(3): 148-54, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22107954

RESUMEN

BACKGROUND: Patient education is the physical therapist's key in guiding patients to a healthier future. When considering patient education, it is important to note that barriers such as limited health literacy can alter the effectiveness of teaching strategies. Health literacy is the ability to comprehend health information and use that information to make informed decisions about one's health and medical care, thus giving individuals the knowledge and skills to optimally function and navigate in the health care environment. While millions of Americans have marginalized literacy skills, older adults aged 65 years and older represent the largest group with compromised general literacy skills in the United States, which significantly contribute to limited health literacy skills. Limited health literacy can have negative consequences on health outcomes due to a lack of knowledge of healthy lifestyle choices, preventative services, disease etiology and management, being able to locate and access appropriate health care services, and carrying out self-care tasks. In addition, limited health literacy increases the risk of hospitalization, the overall cost of health care, and mortality rates. PURPOSE: This article includes (1) the definition of health literacy, (2) the prevalence and consequences of limited health literacy, (3) signs of limited health literacy, (4) health literacy screening and assessment tools, (5) intervention strategies, and (6) implications for physical therapist education. METHODS: PubMed, MEDLINE, CINAHL, and EBSCOHost were searched for articles published from 1990 to 2010 with the descriptors: health literacy, older adults, patient education, functional health literacy, health literacy outcomes, health literacy assessment, and health literacy interventions. CONCLUSION: Limited health literacy affects millions of Americans and plays a significant role in reduced health outcomes for patients. Through patient education and targeted intervention strategies, physical therapists can assist patients in overcoming limitations and enhancing the quality of their health and medical care.


Asunto(s)
Alfabetización en Salud/métodos , Educación del Paciente como Asunto/métodos , Modalidades de Fisioterapia , Anciano , Comunicación , Evaluación Geriátrica , Conocimientos, Actitudes y Práctica en Salud , Humanos , Prevalencia , Relaciones Profesional-Paciente , Estados Unidos
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