8 research outputs found

    Comparison of Eight Remnant Tamaulipan Biotic Province Plant Communities in the Lower Rio Grande Valley Using Multivariate Analyses [Comparación de Ocho Comunidades Vegetales Remanentes de la Provincia Biótica Tamaulipeca el Valle del Río Grande Usando Análisis Multivariada]

    Get PDF
    The Tamaulipan Biotic Province falls within a biogeographic ecotone between temperate North America, the neotropics and the Chihuahuan Desert, and has consequently been defined as “Tamaulipan brushlands.” No quantitative, comparative study has ever been undertaken on the many and varied plant communities that occur in the region. This study compares eight remnant, primary plant communities to test the null hypothesis that the province comprises a single definable vegetation type. Four 50 x 10 m belt-transects were established at each site and woody plants taller than 1 m were recorded to determine species frequency, density, stratification and dominance. Community diversity was calculated using Shannon-Weiner and Simpson indexes. Permutational multiple analysis of variance (PerMANOVA) and Nonmetric Multidimensional Scaling (NMS) examined the relationship between plant community composition and compared their degrees of similarity. Results indicate all eight sites maintain distinct plant communities. Alternate abstract: La Provincia Biótica Tamaulipeca se posiciona en un ecotono biogeográfico entre Norte America templado, los neotrópicos y el Desierto Chihuahuense, y consequentemente se a definido como “matorral Tamaulipeco.” Ningún estudio cuantitativo se a desarollado para enfrentarse a las diversas comunidades vegetatles que ocurren el la región. Éste studio compara ocho communidades remanentes de vegetación primaria para probar la hipótesis nula que la provincia consiste de un solo tipo de vegetación definable. Cuatro transectos de 50 x 10 m fueron establecidos en cada sitio y plantas leñosas arriba de 1 m fueron documentadas para determiner la frequencia, densidad, estratificación y dominancia de especies. La diversitdad de comunidades fue calculada usando los índices de Shannon-Weiner y Simpson. Técnicas de Análisis de Permutaciones y Multiple ANOVA y Escalamiento Multidimensional No Métrico (NMS) examinaron la relación entre la composición de comunidades vegetales y compararon su grado de similitud. Resultados indican que cada de los ocho sitios mantienen comunidades vegetales distintas

    Terrestrial snail communities of the lower rio grande valley are affected by human disturbance and correlate with vegetation community composition

    Get PDF
    The lower Rio Grande Valley of Texas (LRGV) contains a unique, subtropical, semiarid floodplain with most of the few remaining Tamaulipan thorn forests in the United States. Less than 2% of Tamaulipan thorn forest remains, with urban and agricultural conversion potentially threatening diverse plant and animal communities native to the habitat. We performed vegetative community surveys and conducted a comprehensive survey of terrestrial snail communities in intact (refugia sites, minimally altered in recent times) and altered (previously cleared and regrown or restored) Tamaulipan thorn forest habitats of the LRGV. In a comparison of intact and altered sites that have comparable vegetation (paired sites), we found that intact sites had a less species-rich snail community than their altered counterparts, but this difference was not statistically significant. This counterintuitive result, in part reflects the fact that the most species-rich, intact snail communities (i.e., Sabal Palm Forest) have no altered (restored or regrown) counterparts and so were not included in the paired comparisons. A nestedness analysis supports this, finding that these unique intact sites, which have the highest species richness and no comparable restored sites, contain the largest pool of species in South Texas. Species richness of snails significantly correlated with a precipitation gradient. A general linear model incorporating mean canopy cover, mean plant height, plant abundance, and plant species richness shows a significant correlation with snail communities. This study is the only comprehensive survey of the snail communities of the lower Rio Grande Valley. - La cuenca baja del río Grande en Texas (LRGV) contiene una llanura de inundación única, subtropical y semiárida con la mayor´ıa de los remanentes de los bosques espinosos tamaulipecos en los Estados Unidos. Queda menos del 2% del bosque espinoso tamaulipeco, con la conversión a áreas urbanas y agrıcolas potencialmente amenazando las comunidades diversas de plantas y animales nativos del hábitat. Hicimos muestreos de comunidades vegetales y un muestreo comprensivo de comunidades de caracoles terrestres en hábitats de bosques espinosos tamaulipecos intactos (sitios refugio, con poca alteración en tiempos recientes) y perturbados (previamente cortados y recuperados o restaurados) en el LRGV. En una comparaci ´on de los sitios intactos con los perturbados con la vegetación comparable (sitios emparejados), sitios intactos tuvieron comunidades con menos riqueza de especies de caracoles que sus contrapartes alteradas, aunque la diferencia no fue estad´ısticamente significativa. Este resultado contra intuitivo, en parte refleja el hecho de que las comunidades intactas de caracoles mas ricas en especies (o sea, Sabal Palm Forest) no tienen contrapartes alteradas (restauradas o regeneradas) y por eso no fueron incluidas en las comparaciones emparejadas. Un análisis de anidamiento respalda esto, encontrando que estos ´unicos sitios intactos, que tienen la mayor riqueza de especies y ningun sitio comparable restaurado, contienen el grupo más grande de especies en el sur de Texas. La riqueza de especies de caracoles se correlacion significativamente con un gradiente de precipitación. Un modelo lineal general incorporando el promedio de cobertura del dosel, el promedio de altura vegetal, la abundancia de plantas, y la riqueza de especies de plantas muestra una correlación significativa con comunidades de caracoles. Este es el único muestreo comprensivo de las comunidades de caracoles de la cuenca baja del río Grande

    30-Day morbidity and mortality of bariatric metabolic surgery in adolescence during the COVID-19 pandemic – The GENEVA study

    Get PDF
    Background: Metabolic and bariatric surgery (MBS) is an effective treatment for adolescents with severe obesity. Objectives: This study examined the safety of MBS in adolescents during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This was a global, multicentre and observational cohort study of MBS performed between May 01, 2020, and October 10,2020, in 68 centres from 24 countries. Data collection included in-hospital and 30-day COVID-19 and surgery-specific morbidity/mortality. Results: One hundred and seventy adolescent patients (mean age: 17.75 ± 1.30 years), mostly females (n = 122, 71.8%), underwent MBS during the study period. The mean pre-operative weight and body mass index were 122.16 ± 15.92 kg and 43.7 ± 7.11 kg/m2, respectively. Although majority of patients had pre-operative testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (n = 146; 85.9%), only 42.4% (n = 72) of the patients were asked to self-isolate pre-operatively. Two patients developed symptomatic SARS-CoV-2 infection post-operatively (1.2%). The overall complication rate was 5.3% (n = 9). There was no mortality in this cohort. Conclusions: MBS in adolescents with obesity is safe during the COVID-19 pandemic when performed within the context of local precautionary procedures (such as pre-operative testing). The 30-day morbidity rates were similar to those reported pre-pandemic. These data will help facilitate the safe re-introduction of MBS services for this group of patients

    30-day morbidity and mortality of sleeve gastrectomy, Roux-en-Y gastric bypass and one anastomosis gastric bypass: a propensity score-matched analysis of the GENEVA data

    Get PDF
    Background: There is a paucity of data comparing 30-day morbidity and mortality of sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one anastomosis gastric bypass (OAGB). This study aimed to compare the 30-day safety of SG, RYGB, and OAGB in propensity score-matched cohorts. Materials and methods: This analysis utilised data collected from the GENEVA study which was a multicentre observational cohort study of bariatric and metabolic surgery (BMS) in 185 centres across 42 countries between 01/05/2022 and 31/10/2020 during the Coronavirus Disease-2019 (COVID-19) pandemic. 30-day complications were categorised according to the Clavien–Dindo classification. Patients receiving SG, RYGB, or OAGB were propensity-matched according to baseline characteristics and 30-day complications were compared between groups. Results: In total, 6770 patients (SG 3983; OAGB 702; RYGB 2085) were included in this analysis. Prior to matching, RYGB was associated with highest 30-day complication rate (SG 5.8%; OAGB 7.5%; RYGB 8.0% (p = 0.006)). On multivariate regression modelling, Insulin-dependent type 2 diabetes mellitus and hypercholesterolaemia were associated with increased 30-day complications. Being a non-smoker was associated with reduced complication rates. When compared to SG as a reference category, RYGB, but not OAGB, was associated with an increased rate of 30-day complications. A total of 702 pairs of SG and OAGB were propensity score-matched. The complication rate in the SG group was 7.3% (n = 51) as compared to 7.5% (n = 53) in the OAGB group (p = 0.68). Similarly, 2085 pairs of SG and RYGB were propensity score-matched. The complication rate in the SG group was 6.1% (n = 127) as compared to 7.9% (n = 166) in the RYGB group (p = 0.09). And, 702 pairs of OAGB and RYGB were matched. The complication rate in both groups was the same at 7.5 % (n = 53; p = 0.07). Conclusions: This global study found no significant difference in the 30-day morbidity and mortality of SG, RYGB, and OAGB in propensity score-matched cohorts

    Comparison of Eight Remnant Tamaulipan Biotic Province Plant Communities in the Lower Rio Grande Valley Using Multivariate Analyses

    No full text
    The Tamaulipan Biotic Province falls within a biogeographic ecotone between temperate North America, the neotropics and the Chihuahuan Desert, and has consequently been defined as “Tamaulipan brushlands.” No quantitative, comparative study has ever been undertaken on the many and varied plant communities that occur in the region. This study compares eight remnant, primary plant communities to test the null hypothesis that the province comprises a single definable vegetation type. Four 50 x 10 m belt-transects were established at each site and woody plants taller than 1 m were recorded to determine species frequency, density, stratification and dominance. Community diversity was calculated using Shannon-Weiner and Simpson indexes. Permutational multiple analysis of variance (PerMANOVA) and Nonmetric Multidimensional Scaling (NMS) examined the relationship between plant community composition and compared their degrees of similarity. Results indicate all eight sites maintain distinct plant communities

    30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries

    Get PDF
    Background: There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2019 (COVID-19) pandemic and to determine the efficacy of perioperative COVID-19 protective strategies on postoperative symptomatic COVID-19 rates. Methods: We conducted an international cohort study to determine all-cause and COVID-19-specific 30-day morbidity and mortality of BS performed between 01/05/2020 and 31/10/2020. Results: Four hundred ninety-nine surgeons from 185 centres in 42 countries provided data on 7704 patients. Elective primary BS (n = 7084) was associated with a 30-day morbidity of 6.76% (n = 479) and a 30-day mortality of 0.14% (n = 10). Emergency BS, revisional BS, insulin-treated type 2 diabetes, and untreated obstructive sleep apnoea were associated with increased complications on multivariable analysis. Forty-three patients developed symptomatic COVID-19 postoperatively, with a higher risk in non-whites. Preoperative self-isolation, preoperative testing for SARS-CoV-2, and surgery in institutions not concurrently treating COVID-19 patients did not reduce the incidence of postoperative COVID-19. Postoperative symptomatic COVID-19 was more likely if the surgery was performed during a COVID-19 peak in that country. Conclusions: BS can be performed safely during the COVID-19 pandemic with appropriate perioperative protocols. There was no relationship between preoperative testing for COVID-19 and self-isolation with symptomatic postoperative COVID-19. The risk of postoperative COVID-19 risk was greater in non-whites or if BS was performed during a local peak

    30-day morbidity and mortality of sleeve gastrectomy, Roux-en-Y gastric bypass and one anastomosis gastric bypass: a propensity score-matched analysis of the GENEVA data

    No full text
    Background: There is a paucity of data comparing 30-day morbidity and mortality of sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one anastomosis gastric bypass (OAGB). This study aimed to compare the 30-day safety of SG, RYGB, and OAGB in propensity score-matched cohorts. Materials and methods: This analysis utilised data collected from the GENEVA study which was a multicentre observational cohort study of bariatric and metabolic surgery (BMS) in 185 centres across 42 countries between 01/05/2022 and 31/10/2020 during the Coronavirus Disease-2019 (COVID-19) pandemic. 30-day complications were categorised according to the Clavien–Dindo classification. Patients receiving SG, RYGB, or OAGB were propensity-matched according to baseline characteristics and 30-day complications were compared between groups. Results: In total, 6770 patients (SG 3983; OAGB 702; RYGB 2085) were included in this analysis. Prior to matching, RYGB was associated with highest 30-day complication rate (SG 5.8%; OAGB 7.5%; RYGB 8.0% (p = 0.006)). On multivariate regression modelling, Insulin-dependent type 2 diabetes mellitus and hypercholesterolaemia were associated with increased 30-day complications. Being a non-smoker was associated with reduced complication rates. When compared to SG as a reference category, RYGB, but not OAGB, was associated with an increased rate of 30-day complications. A total of 702 pairs of SG and OAGB were propensity score-matched. The complication rate in the SG group was 7.3% (n = 51) as compared to 7.5% (n = 53) in the OAGB group (p = 0.68). Similarly, 2085 pairs of SG and RYGB were propensity score-matched. The complication rate in the SG group was 6.1% (n = 127) as compared to 7.9% (n = 166) in the RYGB group (p = 0.09). And, 702 pairs of OAGB and RYGB were matched. The complication rate in both groups was the same at 7.5 % (n = 53; p = 0.07). Conclusions: This global study found no significant difference in the 30-day morbidity and mortality of SG, RYGB, and OAGB in propensity score-matched cohorts. © 2021, The Author(s)

    30-Day morbidity and mortality of bariatric metabolic surgery in adolescence during the COVID-19 pandemic – The GENEVA study

    No full text
    Background: Metabolic and bariatric surgery (MBS) is an effective treatment for adolescents with severe obesity. Objectives: This study examined the safety of MBS in adolescents during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This was a global, multicentre and observational cohort study of MBS performed between May 01, 2020, and October 10,2020, in 68 centres from 24 countries. Data collection included in-hospital and 30-day COVID-19 and surgery-specific morbidity/mortality. Results: One hundred and seventy adolescent patients (mean age: 17.75 ± 1.30 years), mostly females (n = 122, 71.8%), underwent MBS during the study period. The mean pre-operative weight and body mass index were 122.16 ± 15.92 kg and 43.7 ± 7.11 kg/m2, respectively. Although majority of patients had pre-operative testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (n = 146; 85.9%), only 42.4% (n = 72) of the patients were asked to self-isolate pre-operatively. Two patients developed symptomatic SARS-CoV-2 infection post-operatively (1.2%). The overall complication rate was 5.3% (n = 9). There was no mortality in this cohort. Conclusions: MBS in adolescents with obesity is safe during the COVID-19 pandemic when performed within the context of local precautionary procedures (such as pre-operative testing). The 30-day morbidity rates were similar to those reported pre-pandemic. These data will help facilitate the safe re-introduction of MBS services for this group of patients
    corecore