295 research outputs found
Las razas de manà de Perú
Get PDFEn este estudio sobre manà se diferencian para Perú 47 razas de manà cultivado de las cuales 13 pertenecen a Arachis hypogaeassp. hypogaeavar. hypogaea, 2 a A. hypogaea ssp. hypogaea var. hirsuta, 15 a A. hypogaeassp. fastigiatavar. fastigiata, 15 a A. hypogaeassp. fastigiata var. peruvianay 2 a A. hypogaeassp. fastigiatavar. aecuatoriana. Perú constituye un centro de variación independiente pues sus razas son exclusivas de su territorio, salvo muy pocas excepciones
las razas de mani de bolivia
Get PDFBolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación único en el mundo, lo que señala a Bolivia como una importante fuente de materiales para el mejoramiento de este cultivo de importancia mundial. En este estudio para maní se diferencian para Bolivia 62 razas de maní cultivado de las cuales, 42 pertenecen a Arachis hypogaea L subsp. hypogaea var. hypogaea, 17 a A. hypogaea susbp. fastigiata Waldron var. fastigiata, 1 a A. hypogaea susbp. fastigiata var. vulgaris y 2 a A. hypogaea subsp. fastigiata var. peruviana Krapov. & W. C. Gregory. Bolivia constituye un centro de variación independiente pues sus razas son exclusivas de su territorio, salvo muy pocas excepciones. Bolivia como unidad, se caracteriza por las razas "Crema", "Colorado San Simón", "Bayo americano", "Overo" y "Overo carenado", que se cultivan en todo el país. Se pueden delimitar algunas regiones de mayor diversidad: la región de los Yungas de La Paz, donde se coleccionaron 11 razas de las cuales 3 son exclusivas y la región montañosa de Santa Cruz y Cochabamba, con 18 razas de las cuales 6 son exclusivas. Estas dos regiones pertenecen a la cuenca del Amazonas. Unatercera región se encuentra en el Departamento de Tarija, perteneciente a la cuenca del Plata, donde se coleccionaron 14 razas, de las cuales 2 son exclusivas. Todas estas razas pertenecen a la var. hypogaea. La subsp. fastigiata, presenta un centro de variación muy notable en la cuenca del río Beni, donde en un área muy pequeña se coleccionaron 10 razas, de las cuales 9 son exclusivas. Se destaca Bolivia como un centro de variación único en el mundo y la gran variabilidad del maní señala a Bolivia como una importante fuente de posibilidades para el mejoramiento de este cultivo</div
Las razas de manà en Bolivia
Get PDFBolivia is reagarded as the probable place of origin of the domesticated peanut, and an important world center of unique peanut diversity. As the first published study of its kind or peanut, this paper identifies and describes the infraspecific diversity of the crop in its country of origin and center of diverstity. 62 distinct landraces of Bolivian peanut were identified and systematically described. 42 landraces belong to Arachis hypogaea L. ssp. hypogaea var. hypogaea; 17 to A. hypogaea ssp. fastigiata var. fastigiata; one to A. hypogaea ssp. fastigiata var.vulgaris; and two to A. hypogaea ssp. fastigiata var. peruviana. With very few exceptions, the landraces encountered in Bolivia are almost entirely endemic to that country. The most typical peanuts from Bolivia pertain to the landraces “Crema”, “Colorado San Simón”, “Bayo americano”, “Overo”, and “Overo carenado”, which are widely cultivated throughout the country. A few regions of unusually high peanut diversity can be identified. In the Yungas region of La Paz, 11 landraces were collected, of which three are endemic. In the mountainous regions of Santa Cruz and Cochabamba, 18 landraces were collected, of which six are endemic. The Department of Tarija yielded 14 landraces , of which two are endemic. All of the aforementioned landraces pertain to the botanical variety hypogaea. In contrast, the subspecies fastigiata has a remarkable center or diversity in the watershed of the Rio Beni, where 10 landraces were collected in a fairly small area, nine of which are endemic to that region. This monograph is intended to enhance the knowledge and appreciation of peanut diversity, and facilitate the conservation and use of peanut landraces by scientistis, plant breeders, and farmersBolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación único en el mundo, lo que señala a Bolivia como una importante fuente de materiales para el mejoramiento de este cultivo de importancia mundial. En este estudio para maní se diferencian para Bolivia 62 razas de maní cultivado de las cuales, 42 pertenecen a Arachis hypogaea L subsp. hypogaea var. hypogaea, 17 a A. hypogaea susbp. fastigiata Waldron var. fastigiata, 1 a A. hypogaea susbp. fastigiata var. vulgaris y 2 a A. hypogaea subsp. fastigiata var. peruviana Krapov. & W. C. Gregory. Bolivia constituye un centro de variación independiente pues sus razas son exclusivas de su territorio, salvo muy pocas excepciones. Bolivia como unidad, se caracteriza por las razas "Crema", "Colorado San Simón", "Bayo americano", "Overo" y "Overo carenado", que se cultivan en todo el país. Se pueden delimitar algunas regiones de mayor diversidad: la región de los Yungas de La Paz, donde se coleccionaron 11 razas de las cuales 3 son exclusivas y la región montañosa de Santa Cruz y Cochabamba, con 18 razas de las cuales 6 son exclusivas. Estas dos regiones pertenecen a la cuenca del Amazonas. Unatercera región se encuentra en el Departamento de Tarija, perteneciente a la cuenca del Plata, donde se coleccionaron 14 razas, de las cuales 2 son exclusivas. Todas estas razas pertenecen a la var. hypogaea. La subsp. fastigiata, presenta un centro de variación muy notable en la cuenca del río Beni, donde en un área muy pequeña se coleccionaron 10 razas, de las cuales 9 son exclusivas. Se destaca Bolivia como un centro de variación único en el mundo y la gran variabilidad del maní señala a Bolivia como una importante fuente de posibilidades para el mejoramiento de este cultiv
Las razas de manà de Ecuador
Get PDFEn este estudio para manÃ, se diferencian para Ecuador 51 razas de manà cultivados, de las cuales 18 pertenecen a Arachis hypogaea subsp. hypogaea var. hypogaea, una Arachis hypogaea subsp. hypogaea var. hirsuta, 13 a Arachis hypogaea subsp. fastigiata var. fastigiata, 10 a Arachis hypogaea subsp. fastigiata var. peruviana, 9 a Arachis hypogaea subsp. fastigiata var. aequatoriana; la var. aequatoriana, es casi exclusiva de la República del Ecuador, lo que indica otro genocentro important
Ultrasound-guided laser ablation after excisional vacuum-assisted breast biopsy for small malignant breast lesions: Preliminary results
Get PDFBackground: The purpose of this preliminary study is to evaluate the feasibility of the excisional ultrasound (US) guided vacuum-assisted breast biopsy (VAE), followed by US-guided Laser Interstitial Thermal Therapy (LITT) in the treatment of unifocal ductal breast carcinomas ≤ 1 cm and estimate the ablation rate analyzing the final histopathological results after subsequent surgical excision. Methods: In a single session 11 female patients with unifocal less than a centimeter breast cancer underwent 2 different minimally invasive percutaneous US-guided techniques: a VAE breast biopsy with an 8 G needle to remove the lesion and, immediately after, a LITT ablation in the biopsy site. Four weeks later, all patients underwent radiological follow-up. Afterward, a systematic surgery was performed, the ablation rate was calculated, and iconographic and histological features were correlated. Results: Average maximum diameter of the lesions was 7.6 mm (5-10 mm). No patient reported pain or discomfort during procedure. 1/11 patient (9.1%) reported an early minor complication (a small superficial skin burn). After surgical excision, the histopathological evaluation reported in 10/11 cases (90.9%) complete ablation of the target lesion. In only one case (9.1%) residual cancer was detected. The necrotic-hemorrhagic cavities showed a mean maximum diameter of 27.3 mm (20-35 mm). Conclusions: Laser ablation performed after excisional biopsy could be considered a valid alternative to surgical excision for the treatment of lesions ≤ 1 cm, if carried out by expert radiologists. The association of these minimally invasive percutaneous methods has proven to be reliable, fast, and safe with an ablation rate of 90.9% and excellent aesthetic results. RM and CESM are potentially able to quantifying treatment results and to follow-up the ablation effects
Social interaction, noise and antibiotic-mediated switches in the intestinal microbiota
Get PDFThe intestinal microbiota plays important roles in digestion and resistance
against entero-pathogens. As with other ecosystems, its species composition is
resilient against small disturbances but strong perturbations such as
antibiotics can affect the consortium dramatically. Antibiotic cessation does
not necessarily restore pre-treatment conditions and disturbed microbiota are
often susceptible to pathogen invasion. Here we propose a mathematical model to
explain how antibiotic-mediated switches in the microbiota composition can
result from simple social interactions between antibiotic-tolerant and
antibiotic-sensitive bacterial groups. We build a two-species (e.g. two
functional-groups) model and identify regions of domination by
antibiotic-sensitive or antibiotic-tolerant bacteria, as well as a region of
multistability where domination by either group is possible. Using a new
framework that we derived from statistical physics, we calculate the duration
of each microbiota composition state. This is shown to depend on the balance
between random fluctuations in the bacterial densities and the strength of
microbial interactions. The singular value decomposition of recent metagenomic
data confirms our assumption of grouping microbes as antibiotic-tolerant or
antibiotic-sensitive in response to a single antibiotic. Our methodology can be
extended to multiple bacterial groups and thus it provides an ecological
formalism to help interpret the present surge in microbiome data.Comment: 20 pages, 5 figures accepted for publication in Plos Comp Bio.
Supplementary video and information availabl
The Effect of coronavirus (COVID-19) on breast cancer teamwork: A multicentric survey
Get PDFBackground/Aim: Despite the large amount of clinical data available of Coronavirus-19 (COVID-19), not many studies have been conducted about the psychological toll on Health Care Workers (HCWs). Patients and Methods: In this multicentric descriptive study, surveys were distributed among 4 different Breast Cancer Centers (BCC). BCCs were distinguished according to COVID-19 tertiary care hospital (COVID/No-COVID) and district prevalence (DP) (High vs. Low). DASS-21 score, PSS score and demographic data (age, sex, work) were evaluated. Results: A total of 51 HCWs were analyzed in the study. Age, work and sex did not demonstrate statistically significant values. Statistically significant distribution was found between DASS-21-stress score and COVID/No-COVID (p=0.043). No difference was found in the remaining DASS-21 and PSS scores, dividing the HCWs according to COVID-19-hospital and DP. Conclusion: Working in a COVID-19-hospital represents a factor that negatively affects psychosocial wellbeing. However, DP seems not to affect the psychosocial well-being of BCC HCWs. During the outbreak, psychological support for low risk HCWs should be provided regardless DP
The coordination of cell growth during fission yeast mating requires Ras1-GTP hydrolysis
Get PDFThe spatial and temporal control of polarity is fundamental to the survival of all organisms. Cells define their polarity using highly conserved mechanisms that frequently rely upon the action of small GTPases, such as Ras and Cdc42. Schizosaccharomyces pombe is an ideal system with which to study the control of cell polarity since it grows from defined tips using Cdc42-mediated actin remodeling. Here we have investigated the importance of Ras1-GTPase activity for the coordination of polarized cell growth during fission yeast mating. Following pheromone stimulation, Ras1 regulates both a MAPK cascade and the activity of Cdc42 to enable uni-directional cell growth towards a potential mating partner. Like all GTPases, when bound to GTP, Ras1 adopts an active conformation returning to an inactive state upon GTP-hydrolysis, a process accelerated through interaction with negative regulators such as GAPs. Here we show that, at low levels of pheromone stimulation, loss of negative regulation of Ras1 increases signal transduction via the MAPK cascade. However, at the higher concentrations observed during mating, hyperactive Ras1 mutations promote cell death. We demonstrate that these cells die due to their failure to coordinate active Cdc42 into a single growth zone resulting in disorganized actin deposition and unsustainable elongation from multiple tips. These results provide a striking demonstration that the deactivation stage of Ras signaling is fundamentally important in modulating cell polarity
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