Hierarchical cluster analysis to identify the homogeneous desertification management units.

Since in most mapping models geometric mean of different criteria are used to determine the desertification intensity, one of the most important issues in desertification studies is understanding the similar areas, which require similar management after determining the desertification intensity map. Two similar classes of desertification intensity may require different management due to differences in the criteria that affect its desertification severity. Therefore, after determining the geomorphological facies as the working units in Sistan plain, we used hierarchical cluster analysis to identify the homogeneous environmental management units (HEMUs) based on indices of MEDALUS model. According to the MEDALUS model, the studied area was divided into two categories namely medium and high desertification classes. Working units (geomorphological facies) are classified into five clusters according to HEMUs analysis based on climate, soil, vegetation, and wind erosion criteria. The first cluster (C11) include six facies with moderate and severe desertification; in all of these units the main effective factor was wind erosion, so they need the same management decisions controlling wind erosion. Two working units (1 and 4) with the same desertification severity were placed in two different clusters due to the main factors affecting each other. The results of the Mann-Whitney test showed that the value of the test statistics was 79. Also, the value of Asymp.Sig was obtained to be 0.018, which is less than 0.025 (two-tailed test), and it can be concluded that the classification of work units in the two models, clustering and desertification, is not equal (P<0.05). So It seems that using cluster analysis to identify the same units, which need the same management decision after preparing the desertification intensity, is necessary.

Gestational diabetes induces pancreatic beta-bells apoptosis in adult rat offspring / Diabetes gestacional induce apoptosis de células beta del páncreas en crías de ratas adultas

Several studies indicated that pancreatic ß-cell death occurs in both type 1 and type 2 diabetes. This experimental study was designed to determine the effect of gestational diabetes on the ß-cells in 16-week-old rat offspring. By this aim, adult Wistar rats aged 10-12 weeks were randomly allocated in control and diabetic groups. The diabetic group received 40 mg/kg/body weight of streptozotocin (STZ) on day zero of gestation. After delivery, diabetic offspring of GDM mothers and controls at the age of 16 weeks were sacrificed and pancreases harvested and fixed. The number of ß-cells and were counted by Gomori's method staining. Also, apoptosis in pancreas tissue of diabetic and control offspring was detected by TUNEL assay. Results showed a significant reduction in ß-cell number in offspring of GDM (p<0.05). TUNEL assay showed that the number of apoptotic cells increased in GDM compared to controls (P<0.05). This study revealed that gestational diabetes induces pancreatic beta-cells apoptosis in 16-week-old rat offspring.

Varios estudios indican que la muerte de las células ß del páncreas se produce tanto en la diabetes Tipo 1 como en la Tipo 2. Este estudio experimental fue diseñado para determinar el efecto de la diabetes gestacional en las células ß del páncreas en crías de ratas de 16 semanas. Para ello, ratas Wistar adultas de entre 10-12 semanas fueron asignadas al azar en dos grupos: control y diabetes. El grupo diabetes recibió 40 mg / kg / peso corporal de estreptozotocina (STZ) en el día cero de la gestación. Después del parto, a las 16 semanas, las crías de las madres diabéticas y controles de madres con diabetes gestacional (MDG), fueron sacrificadas para la extracción del páncreas, el cual posteriormente fue fijado. Se contó el número de células ß del páncreas mediante tinción con el método de Gomori. Además, se detectó apoptosis en el tejido del páncreas de la descendencia diabética y el grupo control mediante un ensayo TUNEL. Los resultados mostraron una reducción significativa en el número de células b en la descendencia de MDG (p <0,05). El ensayo TUNEL mostró que el número de células apoptóticas aumentó en MDG en comparación con los controles (P <0,05). Este estudio reveló que la diabetes gestacional induce apoptosis de células ß en el páncreas de crías de ratas de 16 semanas.

Protein capped Cu nanoclusters-SWCNT nanocomposite as a novel candidate of high performance platform for organophosphates enzymeless biosensor.

A biocompatible nanocomposite including bovine serum albumin (BSA) template Cu nanoclusters (CuNCs@BSA) and single-walled carbon nanotubes (SWCNT) was synthesized to fabricate a highly sensitive electrochemical biosensor for paraoxon as a model of organophosphates. The UV-vis, fluorescence and Fourier transform infrared (FTIR) demonstrated that BSA entrapped in the nanocomposite film have been changed in its secondary structure so that it provided an enzyme like activity attributing to the high electrical conductivity of the entrapped copper nanoclusters. Also, the morphology and structure of prepared nanocomposites were investigated by transmission electronic microscopy (TEM) and scanning electron microscopy (SEM). In the prepared nanocomposite, the CuNCs@BSA found to play as a conductive holder as well as an accumulator of redox active centers on the surface of the electrode, and SWCNT improves the electrocatalytic activity along with conductivity of glassy carbon electrode (GCE) surface. The fabricated biosensor exhibited excellent sensitivity, acceptable stability, fast response, and high electrocatalytic activity toward the reduction of paraoxon. The reduction peak current vs paraoxon concentration was linear over the range 50nM to 0.5µM and 0.5-35µM, with a limit of detection of 12.8nM. Notable electrocatalytic properties of the developed electrode toward paraoxon indicated that the nanocomposite possesses a promising potential to fabricate the third generation enzyme-free electrochemical biosensors, bioelectronics and state-of-the-art biomedical devices in the future.