504 research outputs found
Temperature management during cytoreductive surgery with hyperthermic intraperitoneal chemotherapy
In addition to attaining complete or near complete cytoreduction, the instillation of select heated chemotherapeutic agents into the abdominal cavity has offered a chance for cure or longer survival inpatients with peritoneal surface malignancies. While the heating of chemotherapeutic agents enhances cytotoxicity, the resulting systemic hyperthermia has been associated with an increased risk of severe hyperthermia and its associated complications. Factors that have been associated with an increased risk of severe hyperthermia include intraoperative blood transfusions and longer perfusion duration. However, the development of severe hyperthermia still remains largely unpredictable. Thus, at several institutions, cooling protocols are employed during cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). Cooling protocols for CRS-HIPEC are not standardized and may be associated with episodes of severe hyperthermia or alternatively hypothermia. In theory, excessive cooling could result in a decreased effectiveness of the intraperitoneal chemotherapeutic agents. This presumption has been supported by a recent study of 214 adults undergoing CRS-HIPEC, where failure to attain a temperature of 38° C at the end of chemo-perfusion was associated with worse survival. Although not statistically significant, failure to maintain a temperature of 38° C for at least 30 minutes was associated with worse survival. Although studies are limited in this regard, the importance of maintaining a steady state of temperature during the hyperthermic phase of intraperitoneal chemotherapy administration cannot be disregarded. The following article describes the processes and physiological mechanisms responsible for hyperthermia during CRS-HIPEC. The challenges associated with temperature management during CRS-HIPEC and methods to avoid severe hypothermia and hyperthermia are also described
Building disaster preparedness and response capacity in humanitarian supply chains using the Social Vulnerability Index
High-order dispersion mapping of an optical fiber
We report on measurements of high-order dispersion maps of an optical fiber, showing how the ratio between the third and fourth-order dispersion (β3/β4) and the zero-dispersion wavelength (λ0) vary along the length of the fiber. Our method is based on Four-Wave Mixing between short pulses derived from an incoherent pump and a weak laser. We find that the variations in the ratio β3/β4 are correlated to those in λ0. We present also numerical calculations to illustrate the limits on the spatial resolution of the method. Due to the good accuracy in measuring λ0 and β3/β4 (10 -3% and 5% relative error, respectively), and its simplicity, the method can be used to identify fiber segments of good uniformity, suitable to build nonlinear optical devices such as parametric amplifiers and frequency comb generators28342584273FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2012/50259-8; 2015/11779-4; 2017/16151-9; 2018/08988-9; 2019/16793-6Fundação de Amparo à Pesquisa do Estado de São Paulo (2012/50259-8, 2015/11779-4,
2017/16151-9, 2018/08988-9, 2019/16793-6); Coordenação de Aperfeiçoamento de Pessoal de
Nível Superior; Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS) (COL-10-2-05
Ice XII in its second regime of metastability
We present neutron powder diffraction results which give unambiguous evidence
for the formation of the recently identified new crystalline ice phase[Lobban
et al.,Nature, 391, 268, (1998)], labeled ice XII, at completely different
conditions. Ice XII is produced here by compressing hexagonal ice I_h at T =
77, 100, 140 and 160 K up to 1.8 GPa. It can be maintained at ambient pressure
in the temperature range 1.5 < T < 135 K. High resolution diffraction is
carried out at T = 1.5 K and ambient pressure on ice XII and accurate
structural properties are obtained from Rietveld refinement. At T = 140 and 160
K additionally ice III/IX is formed. The increasing amount of ice III/IX with
increasing temperature gives an upper limit of T ~ 150 K for the successful
formation of ice XII with the presented procedure.Comment: 3 Pages of RevTeX, 3 tables, 3 figures (submitted to Physical Review
Letters
A regional earth system data lab for understanding ecosystem dynamics: An example from tropical South America
Comportamiento productivo y reproductivo del ganado holstein rojo, holstein negro y pardo suizo en palmira, valle del cauca
En el Instituto Colombiano Agropecuario-Palmira, se evaluó el comportamiento productivo y reproductivo de 152 vacas; 26 Holstein Rojo (HR), 97 Holstein Negro (HN) y 29 vacas Pardo Suizo (PS), durante el período 1979-1987. La mayor duración de la lactancia, producción de leche y grasa (kg) la presentó la raza HN (324 días, 2545.9 ka, 91.1 kg), seguido de la HR (300 días, 2243.7,81.0 kg) y de la PS (298.2 días, 1886.6 kg, 66.9 kg). los porcentajes de grasa fueron 3.6 (HR) y 3.7010 (HN y PSI. Al tipificar la curva de lactancia, el modelo de mejor ajuste fue: y = A + B (lnt) + C (lnt)2; se observó mayor persistencia en la PS, seguida de la HR. Para el intervalo parto concepción (lPC: 169.0) y servicios por concepción (SC: 2.0) la raza PS presentó mejor desempeño reproductivo, respecto a HN (177.4 Y 2.2) Y HR (195.6 Y 2.2). La raza HR presentó el primer parto a menor edad (3.4 años) y mayor peso (470.5 kg) comparada con la HN (3.5 años y 440.1 kg) y con la PS (3.8 años y 458.1 Kg). El peso promedio al nacimiento para machos y hembras fue mayor en la PS (37.02 kg) que en la HN (36.0) Y HR (36.2). la incidencia de problemas al parto fue mayor en la raza HR (10.9%) y de problemas al puerperio en la raza PS (26.1%). No se encontraron efectos significativos de peso al parto y precipitación sobre producción de leche e IPC, ni relación entre estas variables. Se encontró relación estrecha entre IPC y SC.Three breeds of dairy cattle (26 Red Holstein RH, 97 Black Holstein BH and 29 Brown Swiss BS), were evaluated for reproductive eficiency, and milk production for the years 1979 - 1987 a t the Instituto Colombiano Agropecuario, Palmira. Days of milking, milk and fat production were for BH (324.0days, 2545.9 kg, 91.1 kg) for the RH (300.0 days, 2243.7 kg, 81.0 kg) for the BS (298.2 days, 1886.6 kg, 66.9 kg). % fat average were 3.6% in RH, 3.7 % in BH and BS. The lactation curves for the three breeds were best ajusted with the model: Y=A+B(lnt) + C(lnt)2. Larger persistaency was observed on BS followed by RH. The BS presented better reproductive efficiency than RH and BH with a mean of 169.0,177.4 and 195.6 days, calving data-conception and 2.0, 22 and 22 for number of services per conception. The HR breed had a calving age of 3.4 years and 470.5 kg of calving weight larger than 3.5 years and 440.0 kg for the BH and 3.8 years and 458.1 kg for the BS. Average weight at birth for males and females together BS showed grater weights (37.02 kq), BH and RH showed similar results (36.0 and 362 kg). The incidence of problem at birth was higher for RH (10.90/0) and puerperium problems in BS(21.60,b). Not significal effect of calving weight and rainfall on milk yield and calving date-conception. In most cases there was no correlation between milk yield and calving date-conception. There was a very narow relation between calving date- conception and number of services per conception
Extracellular Matrix Degradation Products and Low-Oxygen Conditions Enhance the Regenerative Potential of Perivascular Stem Cells
Tissue and organ injury results in alterations of the local microenvironment, including the reduction in oxygen concentration and degradation of the extracellular matrix (ECM). The response of perivascular stem cells to these microenvironment changes are of particular interest because of their wide distribution throughout the body and their potential involvement in tissue and organ response to injury. The chemotactic, mitogenic, and phenotypic responses of this stem cell population were evaluated in response to a combination of decreased oxygen concentration and the presence of ECM degradation products. Culture in low-oxygen conditions resulted in increased proliferation and migration of the cells and increased activation of the ERK signaling pathway and associated integrins without a change in cell surface marker phenotype. The addition of ECM degradation products were additive to these processes. Reactive oxygen species within the cells were increased in association with the mitogenic and chemotactic responses. The increased proliferation and chemotactic properties of this stem cell population without any changes in phenotype and differentiation potential has important implications for both in vitro cell expansion and for in vivo behavior of these cells at the site of injury
Promoting prosocial behaviour among Colombian adolescents: the evaluation of a universal school-based program using a multi-informant perspective
The present study evaluated the efficacy of an Italian school-based intervention programme adapted in three Colombian sites (Medellín, Manizales, and Santa Marta) in promoting prosocial behaviour among adolescents. Using a pre-test-post-test design with a multi-informant approach, the present study assessed 451 students (Mage = 12.77, SD = 1.06) of the intervention group and 428 students (Mage = 12.64, SD = 1.01) by using self-report and peer rating measures of prosocial behaviour. After establishing the measurement invariance across time and informants, a latent difference score model showed the positive effect of the intervention programme in improving prosocial behaviour evaluated by peers (Cohen’s d = .379) among Colombian adolescents, across all three sites. Implications of the study will be discussed
Intestinal parasitic infection alters bacterial gut microbiota in children
The study of the burden that parasites can exert upon the bacterial gut microbiota was restricted by the available technologies and their costs. Currently, next-generation sequencing coupled with traditional methodologies allows the study of eukaryotic parasites (protozoa and helminths) and its effects on the human bacterial gut microbiota diversity. This diversity can be altered by a variety of factors such as age, diet, genetics and parasitic infections among others. The disturbances of the gut microbiota have been associated with a variety of illnesses. Children population in developing countries, are especially susceptible to parasitic infections because of the lack of proper sanitation and undernutrition, allowing both, the thriving of intestinal parasites and profound alteration of the gut microbiota. In this work, we have sampled the stool of 23 children from four different children’s care-centers in Medellin, Colombia, and we have identified the eukaryotic parasites by traditional and molecular methodologies coupled with microbial profiling using 16S rDNA sequencing. This mixed methodology approach has allowed us to establish an interesting relationship between Giardia intestinalis and helminth infection, having both effects upon the bacterial gut microbiota enterotypes, causing a switch from a type I to a type II enterotype upon infection
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