La dinámica de un territorio en Yucatán

El hilo conductor del proyecto en Yucatán partió de las preguntas surgidas del Programa Dinámicas Territoriales Rurales (DTR): ¿Cuáles han sido los fenómenos endógenos y exógenos que han influenciado la dinámica del territorio a estudiar en los últimos 20 años?; ¿Cuáles son los fenómenos que podrían explicar el resultado de una mejora de 1990 a 2005 en el nivel de bienestar de los hogares de cuatro municipios en el estado de Yucatán? A las estas dos preguntas hemos añadido la que sigue:¿ha cambiado el bienestar de los hogares de estos municipios en 2009? Un paso previo, necesario para llevar a cabo el estudio, fue indagar si los cuatro municipios yucatecos pueden considerarse como un territorio. Con base en los resultados obtenidos consideramos que los municipios de Cuzamá, Huhí, Acanceh y Homún forman un territorio, que denominamos CHAH a partir de la primera letra de sus nombres. Nuestra investigación se ha basado en el uso de dos metodologías: cualitativa y cuantitativa.Yucatán, México, economías rurales, Latín América, dinámicas territoriales

La dinámica de un territorio en Yucatán. Informe final

En el informe presentamos los principales resultados de la investigación multidisciplinaria en un territorio formado por cuatro municipios del estado mexicano de Yucatán para responder las dos preguntas básicas del Programa Dinámicas Territoriales Rurales (PDTR): ¿cuáles han sido los fenómenos endógenos y exógenos que han influenciado la dinámica del territorio en los últimos 20 años? y ¿cuáles son los fenómenos que podrían explicar el resultado de una mejora durante el periodo en el nivel de bienestar de sus hogares según los resultados de la primera etapa del proyecto? Es común que en los procesos de desarrollo haya población excluida de sus beneficios. Con el fin de estudiar este aspecto en el territorio yucateco añadimos respuesta a la pregunta: ¿cuáles son los niveles de pobreza y desigualdad prevalecientes en el territorio?Yucatán, México, economías rurales, América Latina, dinámicas territoriales

Differential criterion of a bubble collapse in viscous liquids

The present work is devoted to a model of bubble collapse in a Newtonian viscous liquid caused by an initial bubble wall motion. The obtained bubble dynamics described by an analytic solution significantly depends on the liquid and bubble parameters. The theory gives two types of bubble behavior: collapse and viscous damping. This results in a general collapse condition proposed as the sufficient differential criterion. The suggested criterion is discussed and successfully applied to the analysis of the void and gas bubble collapses.Comment: 5 pages, 3 figure

Retrospective outcome analysis of urethroplasties performed for various etiologies in a single South African centre

This is the author’s version of a work that was accepted for publication of the article: African Journal of Urology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in African Journal of Urology, VOL 18, Issue 3, 2012, DOI: 10.1016/j.afju.2012.03.001.Objectives: To compare the results of anastomotic versus augmentation urethroplasty (buccal mucosa graft (BMG) onlay), as well as dorsal versus ventral BMG techniques. Methods: A retrospective audit of 69 patients who underwent urethroplasty at Eersteriver Hospital in Cape Town, South Africa between October 2004 and July 2011 was undertaken. Analysis included stricture etiology, location and length, type of surgery performed as well as complication rates over the follow-up period. Results: The predominant stricture etiologies were traumatic and infective causes (55%), with a mean stricture length of 3 cm (0.5–15 cm). Forty two patients had bulbar urethra strictures (61%), with 8 (11%) located in the posterior, and penile & bulbar regions, respectively. The remaining strictures were located in the penile urethra (16%). Surgery performed included bulbar (12) and membranous anastomotic (8) urethroplasty, ventral (13) and dorsal (22) buccal mucosa onlay grafts (BMG), and 2-stage urethroplasty (14). Overall stricture recurrence was seen in 9 patients (13%), including 1 patient (8%) of the anterior end-to-end anastomotic group compared to 2 patients (6%) of the onlay BMG group (p = 0.77). The re-stricture rates were 5% and 8% in the dorsal (1/22) and ventral BMG onlay groups (1/13), respectively (p = 0.72)

Simulated genetic efficacy of metapopulation management and conservation value of captive reintroductions in a rapidly declining felid

In South Africa, cheetah (Acinonyx jubatus) occur as a relictual, unmanaged population of ‘free‐roamers’, a managed metapopulation across fenced reserves, and in various captive facilities. To ensure that the Cheetah Metapopulation Project (CMP) is not at risk of losing overall genetic variation to drift or inbreeding, we propose various interventions, including exchanges between free‐roamers and the metapopulation or supplementation with unrelated individuals from captivity. Simulated trajectories of genetic diversity under such intervention strategies over time could directly inform conservation action and policy towards securing the long‐term genetic integrity of the CMP. Single Nucleotide Polymorphisms (SNPs) were genotyped for 172 adult cheetahs across the free‐roamer population, the metapopulation, and three major captive facilities. Management intervention trajectory models were tested including, (1) no intervention, (2) genetic exchange between free‐roamers and the metapopulation, (3) translocation from a single captive facility and (4) translocation from several captive facilities into the metapopulation. Discriminant Analysis of Principal Components (DAPC) showed that two captive populations are highly differentiated from the metapopulation and each other, whilst the third captive and free‐roamer populations are genetically more similar to the metapopulation. Simulated genetic variation over 25 generations indicated that models 1 and 2 show significant losses of heterozygosity due to genetic drift and present a proportional increase in the frequencies of 1st‐ and 2nd‐degree relatives, whilst this variation and pairwise relatedness remain relatively constant under models 3 and 4. We emphasise the potential importance of captive facilities as reservoirs of genetic diversity in metapopulation management and threatened species recovery

Neutrophil Gelatinase-Associated Lipocalin and its Receptors in Alzheimer's Disease (AD) Brain Regions:Differential Findings in AD with and without Depression

Co-existing depression worsens Alzheimer’s disease (AD) pathology. Neutrophil gelatinase-associated lipocalin (NGAL) is a newly identified (neuro)inflammatory mediator in the pathophysiologies of both AD and depression. This study aimed to compare NGAL levels in healthy controls, AD without depression (AD–D), and AD with co-existing depression (AD+D) patients. Protein levels of NGAL and its receptors, 24p3R and megalin, were assessed in nine brain regions from healthy controls (n = 19), AD–D (n = 19), and AD+D (n = 21) patients. NGAL levels in AD–D patients were significantly increased in brain regions commonly associated with AD. In the hippocampus, NGAL levels were even further increased in AD+D subjects. Unexpectedly, NGAL levels in the prefrontal cortex of AD+D patients were comparable to those in controls. Megalin levels were increased in BA11 and amygdala of AD+D patients, while no changes in 24p3R were detected. These findings indicate significant differences in neuroimmunological regulation between AD patients with and without co-existing depression. Considering its known effects, elevated NGAL levels might actively promote neuropathological processes in AD with and without depression

Outcomes of laboratory-confirmed SARS-CoV-2 infection during resurgence driven by Omicron lineages BA.4 and BA.5 compared with previous waves in the Western Cape Province, South Africa

OBJECTIVE: We aimed to compare clinical severity of Omicron BA.4/BA.5 infection with BA.1 and earlier variant infections among laboratory-confirmed SARS-CoV-2 cases in the Western Cape, South Africa, using timing of infection to infer the lineage/variant causing infection. METHODS: We included public sector patients aged ≥20 years with laboratory-confirmed COVID-19 between 1-21 May 2022 (BA.4/BA.5 wave) and equivalent prior wave periods. We compared the risk between waves of (i) death and (ii) severe hospitalization/death (all within 21 days of diagnosis) using Cox regression adjusted for demographics, comorbidities, admission pressure, vaccination and prior infection. RESULTS: Among 3,793 patients from the BA.4/BA.5 wave and 190,836 patients from previous waves the risk of severe hospitalization/death was similar in the BA.4/BA.5 and BA.1 waves (adjusted hazard ratio (aHR) 1.12; 95% confidence interval (CI) 0.93; 1.34). Both Omicron waves had lower risk of severe outcomes than previous waves. Prior infection (aHR 0.29, 95% CI 0.24; 0.36) and vaccination (aHR 0.17; 95% CI 0.07; 0.40 for at least 3 doses vs. no vaccine) were protective. CONCLUSION: Disease severity was similar amongst diagnosed COVID-19 cases in the BA.4/BA.5 and BA.1 periods in the context of growing immunity against SARS-CoV-2 due to prior infection and vaccination, both of which were strongly protective