Stability & durability of self-driven photo-detective parameters based on Sn1-ß Sb ß Se (ß = 0, 0.05, 0.10, 0.15, 0.20) ternary alloy single crystals.

In the present investigation Sn1-ß Sb ß Se crystals are grown using the direct vapor transport method. The crystals after growth were analyzed by EDAX and XPS to confirm the elemental composition. The surface morphological properties were studied by scanning electron microscope, confirming a flat surface and layered growth of the Sn1-ß Sb ß Se crystals. The structural properties studied by X-ray diffraction and high-resolution transmission electron microscopy confirm the orthorhombic structure of the grown Sn1-ß Sb ß Se crystals. The Raman spectroscopic measurements evince the presence of B2g and Ag vibration modes. The PL intensity peak at ∼400 nm to 500 nm confirms the energy band gap. The indirect energy band gap of 1.18 eV was evaluated using Tauc plot by employing UV-visible spectroscopy making it a promising candidate for optoelectronic and photonic applications. The pulse photo response of pure and doped samples was studied under a monochromatic source of wavelength 670 nm and intensity of 30 mW cm-2 at zero biasing voltage firstly on day one and then the same samples were preserved for 50 days and the stability of the photodetectors was observed. Photodetector parameters such as rise time, decay time, photocurrent, responsivity, sensitivity, and detectivity were observed, and evaluated results are presented in this article.

Starch bio-based composite active edible film functionalized with Carum carvi L. essential oil: antimicrobial, rheological, physic-mechanical and optical attributes.

In the present study, the antimicrobial, rheological, mechanical, barrier and optical properties of Carrageenan and Manihot esculenta (composite) starch biobased edible film incorporated with caraway (Carum carvi L.) essential oil (EO) were investigated. The Minimum Inhibitory Concentration (MIC) of caraway oil against B. cereus, E. coli, P. aeruginosa and S. aureus were found to be 0.6, 1.4, 1.4 and 0.8% respectively. The Gas Chromatography- Mass Spectroscopy (GC-MS) of caraway EO expressed a distinct chromatogram peak for phenolic compounds. Rheological results of Film-Forming Solution (FFS) revealed solid-like viscoelastic behavior. Incorporation of caraway EO in the film caused significant (P < 0.05) increase in moisture, moisture absorption, bio-degradability in terms of film solubility, L value, total color difference (ΔE), haziness and transparency value, however, significantly (P < 0.05) decreased tensile strength and whiteness index were observed. The zone of inhibition of caraway EO incorporated films against all test bacteria were highly significant (P < 0.01) than control whereas antibacterial activity was found more towards gram-positive bacteria than gram-negative bacteria. No significant (P>0.05) changes in thickness, density, water activity, swelling, elongation at break, water vapor transmission rate, a and b value were observed with increasing caraway EO concentration. These results with some good rheological, physic-mechanical, antimicrobial and optical characteristics suggest the application of such active film into a variety of foods with improved food safety and quality. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05028-1.

Flexible paper based piezo-resistive sensor functionalised by 2D-WSe2 nanosheets.

High-performance electronics demand extremely sensitive piezo-resistive sensors with important features such as low-fabrication cost, easy implementation, low power consumption and high-pressure sensitivity over broad pressure range. Herein, we report a flexible piezo-resistive paper-based device functionalised by WSe2 nanosheets. An efficient and low-cost fabrication strategy using Whatman filter paper and tissue paper is adopted for versatile sensing applications. The WSe2 nanosheets were synthesized by high-yield and size-controlled liquid phase exfoliation technique. The flexible WSe2 nanosheets-paper sensor shows excellent response in broad pressure range of 1 Pa-100 kPa with exceptionally high sensitivity of 29.24 kPa-1, current responsivity of 70 and response time of 100 ms. The pressure sensor is also employed to recognize the pressure generated due to finger tapping. Encouragingly, the piezo-resistive sensors can also sense extremely small pressure differences of about 1.4 Pa generated by water drops.

Novel dual incretin agonist peptide with antidiabetic and neuroprotective potential.

Glucose-dependent insulinotropic hormone (GIP) and glucagon-like peptide-1 (GLP-1) are incretin hormones that exert an array of beneficial actions on metabolism and cognitive function. GLP-1-based therapeutics have been highly successful in terms of obesity and diabetes management, however GIP therapies have found no clinical utility to date. In the present study we describe, for the first time, the therapeutic effectiveness of a novel GIP/GLP-1 hybrid peptide based on the amino acid sequences of GIP, GLP-1 and the clinically approved GLP-1 mimetic, exendin-4. The hybrid peptide, N-ac(d-Ala2)GIP/GLP-1-exe, was enzymatically stable for up to 12 h when incubated with DPP-4. N-ac(d-Ala2)GIP/GLP-1-exe significantly (P < 0.001) stimulated insulin secretion from BRIN-BD11 cells and isolated mouse islets, and evoked dose-dependent increases (P < 0.001) in cAMP production in both GIP-R and GLP-1-R transfected cells. In mice, injection of the hybrid in combination with glucose significantly (P < 0.001) reduced glucose and increased insulin concentrations, with metabolic actions evident (P < 0.05) 8 h post-injection. Twice-daily injection of N-ac(d-Ala2)GIP/GLP-1-exe to high fat fed (HFF) mice for 28 days significantly (P < 0.05-P < 0.001) reduced body weight, HbA1c, circulating glucose and insulin concentrations. Furthermore, both oral and i.p. glucose tolerance were improved (P < 0.001) and insulin sensitivity enhanced. The hybrid peptide also increased (P < 0.05-P < 0.001) beta cell number, islet area, pancreatic insulin content and islet insulin secretory responsiveness in HFF mice. Finally, N-ac(d-Ala2)GIP/GLP-1-exe treated mice exhibited improved (P < 0.01) recognition memory which was accompanied by enhanced (P < 0.05-P < 0.001) hippocampal neurogenesis, synapse formation and reduced neuronal oxidative stress. These data demonstrate for the first time the beneficial actions of the novel GIP/GLP-1 hybrid, N-ac(d-Ala2)GIP/GLP-1-exe, on glucose homeostasis and memory function in diabetes.

Experimental and kinetics study for phytoremediation of sugar mill effluent using water lettuce (Pistia stratiotes L.) and its end use for biogas production.

In present study, the performance of phytoremediation by Pistia stratiotes on sugar mill effluent (SME) and its end use for biogas production are investigated. The objectives of the study are to determine the nutrient and pollution reduction efficiency of P. stratiotes from SME and evaluation of its biomass as a feedstock for biogas production. Various concentrations of SME (25, 50, 75, and 100%) were remediated by Pistia stratiotes (initial weight; 150 g) outdoor for 60 days under batch mode experimental setup. The results showed that P. stratiotes achieved marked reduction in nutrient (TKN, 72.86%; TP, 71.49%) and pollutant load (EC, 25.69%; TDS, 57.26%; BOD, 69.40%; COD, 61.80%; Ca2+, 56.79%; Mg2+, 55.01%; Na+, 42.86%; K+, 54.38%; MPN, 78.13%; SPC, 60.13%) from 75% SME at the end of the experiment. The highest biomass (328.48 ± 2.04 g) and chlorophyll content (3.62 ± 3.04 mg/g) were also achieved with 75% SME. The dried biomass of P. stratiotes (from 75% SME) was inoculated with cow dung (10% w/v) and diluted with distilled water (1:10). The whole content was used as a substrate for the biogas production within hydraulic retention time (HRT) of 30 days at room temperature. Substrate parameters such as pH, TS (%), COD (mg/L), TKN (%), TOC (%), VS (%), and C/N ratio were reduced from 7.85 to 6.0, 66.65 to 28.65%, 12,900 to 2800 mg/L, 0.95 to 0.75%, 45.54 to 19.5%, 76.87 to 28.78%, and 47.94 to 26.00, respectively, in 30 days of HRT. About 8478.6 mL of cumulative biogas production was evaluated by modified Gompertz equation. Thus, the present investigation not only achieved efficient nutrient and pollution reduction from SME but also proved the potential of P. stratiotes for biogas production.

Stable multi-GeV electron accelerator driven by waveform-controlled PW laser pulses.

The achievable energy and the stability of accelerated electron beams have been the most critical issues in laser wakefield acceleration. As laser propagation, plasma wave formation and electron acceleration are highly nonlinear processes, the laser wakefield acceleration (LWFA) is extremely sensitive to initial experimental conditions. We propose a simple and elegant waveform control method for the LWFA process to enhance the performance of a laser electron accelerator by applying a fully optical and programmable technique to control the chirp of PW laser pulses. We found sensitive dependence of energy and stability of electron beams on the spectral phase of laser pulses and obtained stable 2-GeV electron beams from a 1-cm gas cell of helium. The waveform control technique for LWFA would prompt practical applications of centimeter-scale GeV-electron accelerators to a compact radiation sources in the x-ray and γ-ray regions.

Control of campylobacter in poultry industry from farm to poultry processing unit: A review.

Campylobacter is an emerging zoonotic bacterial threat in the poultry industry. Most of the human cases of campylobacteriosis recorded have revealed their poultry origins. Various control measures have been employed both at the farm and processing levels to combat with it. The antibiotic treatment, phage therapy, competitive exclusion, and vaccination have been adapted at the farm level to reduce colonization of Campylobacter in poultry gut. While prevention of intestinal spillage, scheduled slaughter, logistic slaughter, chemical decontamination of carcasses are recommended to reduce contamination during processing. The postharvest interventions such as heat treatment, freezing, irradiation of contaminated carcass can effectively reduce Campylobacter contamination. Thus, integrated approaches are required to tackle infection of Campylobacter in humans.

Development and quality assessment of carrageenan incorporated low fat chevon patties.

The present study was conducted to develop and assess the quality of carrageenan incorporated chevon patties with the objective of reducing fat content. Efficacy of carrageenan as fat replacers (0.3, 0.6 & 0.9 %) was assessed for development of low fat chevon patties. Emulsion stability and cooking yield increased with the increase in levels of carrageenan. Significantly (P < 0.05) lower fat and cholesterol contents and higher moisture and fat retention were observed in formulation with carrageenan. No significant difference in the mineral content in either of the treatment was recorded. Incorporation of fat replacer in chevon patties demonstrated significant effect on all the textural parameters except adhesiveness. Results of color value illustrated that lightness (L*) value differ significantly. Sensory scores were higher or comparable for patties containing 0.6 % carrageenan as compared to control. Hence, carrageenan was observed to be suitable as fat replacer for producing low fat chevon meat patties.

Beneficial metabolic actions of a stable GIP agonist following pre-treatment with a SGLT2 inhibitor in high fat fed diabetic mice.

The purpose of the present study was to examine if a stable glucose-dependent insulinotropic polypeptide (GIP) agonist could exert beneficial metabolic control in diabetic mice which had been pre-treated with sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA). High fat fed mice administered low dose streptozotocin (STZ) received vehicle, DAPA once-daily over 28 days, or DAPA once-daily for 14 days followed by (DAla(2))GIP once-daily for 14 days. Energy intake, body weight, glucose and insulin concentrations were measured at regular intervals. Glucose tolerance, insulin tolerance test, dual-energy X-ray absorptiometry (DEXA) and pancreatic histology were examined. Once-daily administration of (DAla(2))GIP for 14 days in high fat fed diabetic mice pre-treated with DAPA demonstrated significant decrease in body weight, blood glucose and increased insulin concentrations which were independent of changes in energy intake. Similarly, glucose tolerance, glucose-stimulated insulin secretion, insulin sensitivity and HOMA-ß were significantly enhanced in (DAla(2))GIP-treated mice. DEXA analysis revealed sustained percentage body fat loss with no changes in lean mass, bone mineral content and density. Pancreatic immunohistochemical analysis revealed decreased islet number and increases in islet area, beta cell area and pancreatic insulin content. The DAPA-induced increase in alpha cell area was also reversed. Additional acute in vitro and in vivo experiments confirmed that the impaired action of (DAla(2))GIP under hyperglycaemic-induced conditions was significantly reversed by DAPA treatment. These data demonstrate that (DAla(2))GIP can exert beneficial metabolic control in high fat fed diabetic mice pre-treated with DAPA. The results highlight possibility of a targeted and personalized approach using a GIP agonist and SGLT2 inhibitor for the treatment of type 2 diabetes.

Sustained treatment with a stable long-acting oxyntomodulin analogue improves metabolic control and islet morphology in an experimental model of type 1 diabetes.

AIM: To assess the therapeutic benefits of regulatory peptides other than insulin, which have to date received limited consideration in the context of type 1 diabetes. METHODS: We assessed the effects of subchronic administration of the stable, oxyntomodulin (Oxm) analogue, (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL], for 28 days in streptozotocin (STZ)-induced insulin-deficient diabetic mice. RESULTS: Twice-daily injection with (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL] significantly countered the excessive food and fluid intake in STZ-induced diabetic mice, and maintained normal body weight. Lean body mass was normalized, whilst fat mass was significantly increased compared with control STZ-induced diabetic mice. In addition, circulating glucose was significantly reduced by the Oxm analogue, whilst plasma and pancreatic insulin concentrations were increased and glucagon decreased by day 28. Plasma lipid profile was normalized by (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL] administration and circulating amylase was not significantly altered by induction of diabetes or Oxm analogue therapy. This was associated with significantly improved glucose tolerance and insulin secretion. Peripheral insulin sensitivity was also significantly improved by Oxm analogue treatment. Histological examination of pancreata showed beneficial elevations of total islet and ß-cell area, associated with an increase in the number of smaller-sized islets. Further analysis revealed enhanced islet cell proliferation relative to apoptosis in Oxm analogue-treated mice. CONCLUSION: These studies emphasize the potential of stable Oxm-based peptides, such as (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL], as therapeutic agents for insulin-deficient type 1 diabetes.

Stable oxyntomodulin analogues exert positive effects on hippocampal neurogenesis and gene expression as well as improving glucose homeostasis in high fat fed mice.

The weight-lowering and gluco-regulatory actions of oxyntomodulin (Oxm) have been well-documented however potential actions of this peptide in brain regions associated with learning and memory have not yet been evaluated. The present study examined the long-term actions of a stable acylated analogue of Oxm, (dS(2))Oxm(K-γ-glu-Pal), together with parent (dS(2))Oxm peptide, on hippocampal neurogenesis, gene expression and metabolic control in high fat (HF) mice. Groups of HF mice (n = 12) received twice-daily injections of Oxm analogues (both at 25 nmol/kg body weight) or saline vehicle (0.9% wt/vol) over 28 days. Hippocampal gene expression and histology were assessed together with evaluation of energy intake, body weight, non-fasting glucose and insulin, glucose tolerance, insulin sensitivity and lipids. Oxm analogues significantly reduced body weight, improved glucose tolerance, glucose-mediated insulin secretion, insulin sensitivity, islet architecture and lipid profile. Analysis of brain histology revealed significant reduction in hippocampal oxidative damage (8-oxoguanine), enhanced hippocampal neurogenesis (doublecortin) and improved hippocampal and cortical synaptogenesis (synaptophysin) following treatment. Furthermore, Oxm analogues up-regulated hippocampal mRNA expression of MASH1, Synaptophysin, SIRT1, GLUT4 and IRS1, and down-regulated expression of LDL-R and GSK3ß. These data demonstrate potential of stable Oxm analogues, and particularly (dS(2))Oxm(K-γ-glu-Pal) to improve metabolic function and enhance neurogenesis, synaptic plasticity, insulin signalling and exert protective effects against oxidative damage in hippocampus and cortex brain regions in HF mice.

Minocycline-loaded cellulose nano whiskers/poly(sodium acrylate) composite hydrogel films as wound dressing.

In this work, antibiotic drug Minocycline (Mic) loaded cellulose nano-whiskers (CNWs)/poly(sodium acrylate) hydrogel films were prepared and investigated for their drug releasing capacity in physiological buffer solution (PBS) at 37 °C. The (CNWs)/poly(sodium acrylate) film, containing 9.7% (w/w) of CNWs, demonstrated Mic release of 2500 µg/g while the plain poly(acrylate) film showed 3100 µg/g of drug release. In addition, with the increase in the concentration of cross-linker N,N'-methylene bisacrylamide (MB) from to, the drug release from the resulting films decreased from 507 to 191 µg/g. The release exponent 'n' for films with different compositions was found in the range of 0.45 to 0.89, thus indicating non-Fickian release mechanism. The Schott model was employed to interpret the kinetic drug release data successfully. The film samples poly(SA) and CNWs/poly(SA) (both not containing drug) showed thrombus formation of 0.010±0.001 g and 0.007±0.001 g, respectively, thus showing the non-thrombogenic behavior. In percent Hemolysis, both of the film samples of 1.136±0.012 and 0.5±0.020, respectively, thus indicating non-hemolytic behavior. In addition, both of the film samples demonstrated protein adsorption of 49.02±0.59µ g/µL and 51.20±0.51 µg/µL per cm(2), thus revealing a fair degree of protein adsorption. Finally, the Mic-loaded films showed fair anti-fungal and antibacterial properties.

Microbial quality, instrumental texture, and color profile evaluation of edible by-products obtained from Barbari goats.

AIM: The study was conducted to estimate the contribution of edible byproducts of Barbari kids to their live and carcass weight as well as to assess textural and color characteristics and microbiological status of these byproducts. MATERIALS AND METHODS: Percent live weight, Percent carcass weight, Texture, color, and microbiological analysis was done for edible byproducts viz. liver, heart, kidney, spleen, brain and testicle and longissimus dorsi muscle was taken as a reference. RESULTS: The edible byproducts of Barbari kids constitute about 3% of the live weight of an animal of which liver contributed maximum (1.47%) followed by testicles (0.69%) and heart (0.41%). While the same constituted 3.57, 1.70, and 0.99%, respectively on carcass weight. There was significant (p<0.05) difference among all organs regarding textural properties. Liver required the maximum shear force and work of shear (121.48N and 32.19 kg-sec) followed by spleen and heart. All organs revealed characteristics color values (L*, a*, b*, chroma, and hue) which were significantly different (p<0.05) from muscle values. The total viable count, coliform count showed slight differences for all organs studied. The staphylococcus counts were low with little differences among organs. CONCLUSION: Edible byproducts have a significant contribution to carcass weight which could enhance total edible portion of the carcass. Efficient utilization of these by-products returns good source of revenue to the meat industries. Textural and color analysis give information for their incorporation in comminuted meat products, and microbial study tells about the storage study. However, study was in the preliminary and basic step forward toward better utilization of 3% of live animal which could increase the saleable cost of animal by 6.94%.

Antagonism of gastric inhibitory polypeptide (GIP) by palmitoylation of GIP analogues with N- and C-terminal modifications improves obesity and metabolic control in high fat fed mice.

Compromise of gastric inhibitory polypeptide (GIP) receptor signalling represents a possible therapeutic strategy for the treatment of obesity-related diabetes. This study has characterised and evaluated the C-terminally fatty acid derivatised GIP analogues, GIP(3-30)Cex-K(40)[Pal] and Pro(3)GIP(3-30)Cex-K(40)[Pal], as potential GIP inhibitors. Both GIP analogues lack the two N-terminal amino acids cleaved by DPP-4 and have addition of nine amino acids from the C-terminal of exendin(1-39), Cex. GIP(3-30)Cex-K(40)[Pal] and Pro(3)GIP(3-30)Cex-K(40)[Pal] effectively (p < 0.01 to p < 0.001) inhibited GIP-induced cAMP production and insulin secretion in vitro. In normal mice, GIP(3-30)Cex-K(40)[Pal] and Pro(3)GIP(3-30)Cex-K(40)[Pal] displayed a significant (p < 0.05 to p < 0.001) and prolonged inhibitory effect on GIP-induced glucose-lowering and insulin-releasing actions. When injected once daily for 21 days in obese-diabetic high fat fed mice, both GIP(3-30)Cex-K(40)[Pal] and Pro(3)GIP(3-30)Cex-K(40)[Pal] significantly reduced body weight (p < 0.01 to p < 0.001) and lowered circulating glucose (p < 0.001) and insulin (p < 0.01 to p < 0.001) concentrations. The observed beneficial changes were independent of effects on energy intake, locomotor activity or metabolic rate. Oral and intraperitoneal glucose tolerance were significantly (p < 0.05 to p < 0.001) improved in both treatment groups at the end of the study, despite reduced glucose-induced plasma insulin concentrations. This improvement of metabolic control was accompanied by enhanced (p < 0.05 to p < 0.01) insulin sensitivity compared with high fat controls. These data demonstrate the potential offered by GIP(3-30)Cex-K(40)[Pal] and Pro(3)GIP(3-30)Cex-K(40)[Pal] for the treatment of obesity-related diabetes.

"Effect of sorbic acid on the storage quality of Kaladhi-an acid coagulated milk product".

The present study was conducted to determine the effect of three different levels of sorbic acid (0.1 %, 0.2 % and 0.3 %) on the shelf life and storage quality of Kaladhi. Kaladhi was prepared from pasteurized buffalo milk standardized to 6 % fat and 9 % SNF with coagulation at 40 °C using 5 % lactic acid as a coagulant. Kaladhi prepared without sorbic acid served as control and was compared with the products treated with different levels of sorbic acid for a storage period of 35 days at ambient temperature. The results showed a significant (P < 0.05) effect of sorbic acid on most of the physicochemical parameters i.e. titratable acidity, free fatty acid content (% oleic acid) and thiobarbituric acid value which showed a decreasing trend with increasing concentration of sorbic acid. However, a non-significant (P > 0.05) effect of sorbic acid was observed on pH and proximate parameters of the product. Kaladhi treated with 0.3 % sorbic acid retained most desirable physicochemical and sensory properties throughout the storage period hence, was considered the best.

Phycoremediation of textile wastewater by unicellular microalga Chlorella pyrenoidosa.

The potential application of microalga Chlorella pyrenoidosa was investigated for phycoremediation of textile wastewater. Two 15 days batch experiment containing autoclaved and unautoclaved textile wastewater were performed to measure the efficiency of alga to remediate the wastewater. Experiments were set at equivalent external conditions and pollutant load was measured on alternate of 5 days to determine the pollutant removal efficiency of alga. Alga was found to be more efficient in removal of pollutants load in autoclaved wastewater; agents of eutrophication such as nitrate and phosphate are reduced by 62% ±0.5 and 87% ±0.7 respectively while organic load in terms of BOD is reduced by 81% ±0.2 whereas, In unautoclaved wastewater in presence of algal-bacterial consortium, nitrate and phosphate were removed by 81% ±1 and 36% ±2.2 while BOD is reduced by 73% ±1.6 only. Another time dependent experiment of dye removal was also performed to measure the adsorption potential of selected dried algal biomass. An equal amount of dried algal biomass was introduced to various range of textile wastewater simulated with methylene blue (MB) dye. The maximum colour removal was observed afterduration of 30 minutes by dry algal biomass.

CNWs loaded poly(SA) hydrogels: effect of high concentration of CNWs on water uptake and mechanical properties.

In this work, poly(sodium acrylate) (poly(SA)) hydrogel films, doped with cellulose nano-whiskers (CNWs), are prepared via free radical polymerization of sodium acrylate (SA) in aqueous medium. The CNWs were added into the polymerization feed mixture, in the concentration range of 4.8-24.3 wt% of monomer and the resulting CNWs/poly(SA) hydrogel films were investigated for their water absorbency in the physiological fluid (PF). The addition of CNWs caused a decrease in the equilibrium water uptake. The kinetic water uptake data of all hydrogel samples were best interpreted by the second order kinetic. The water vapor permeation studies were also carried out. The water vapor transmission rate (WVTR) of all the film samples was quite low. The mechanical properties of films such as tensile strength (TS) and percent elongation (PE) varied with the CNWs content. All the film samples showed fair folding endurance (FE), with more than 600 times folding without suffering from any crack.

Variability in radiative properties of major aerosol types: a year-long study over Delhi--an urban station in Indo-Gangetic Basin.

Aerosol measurements over an urban site at Delhi in the western Ganga basin, northern India, were carried out during 2009 using a ground-based automatic sun/sky radiometer to identify their different types and to understand their possible radiative implications. Differentiation of aerosol types over the station was made using the appropriate thresholds for size-distribution of aerosols (i.e. fine-mode fraction, FMF at 500 nm) and radiation absorptivity (i.e. single scattering albedo, SSA at 440 nm). Four different aerosol types were identified, viz., polluted dust (PD), polluted continent (PC), mostly black carbon (MBC) and mostly organic carbon (MOC), which contributed ~48%, 32%, 11% and 9%, respectively to the total aerosols. Interestingly, the optical properties for these aerosol types differed considerably, which were further used, for the first time, to quantify their radiative implications over this station. The highest atmospheric forcing was observed for PC aerosol type (about +40 W m(-2), along with the corresponding atmospheric heating rate of 1.10 K day(-1)); whereas the lowest was for MBC aerosol type (about +25 W m(-2), along with the corresponding atmospheric heating rate of 0.69 K day(-1)).

Effects of chronic exposure of clonal ß-cells to elevated glucose and free fatty acids on incretin receptor gene expression and secretory responses to GIP and GLP-1.

AIM: The incretin effect, mediated by glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), is impaired in type 2 diabetes. METHODS: This study examines the effects of prolonged exposure to elevated glucose and free fatty acids in clonal BRIN BD11 cells on GIP and GLP-1 action. RESULTS: Glucotoxic conditions (18 h) had no effect on GIP- or GLP-1-mediated insulinotropic responses. In contrast, 48 h glucotoxic culture impaired (p < 0.05 to p < 0.001) insulin release in response to GLP-1, and particularly GIP. Culture under lipotoxic conditions (18 h) impaired (p < 0.05 to p < 0.001) the insulin-releasing effect of GIP, but was without effect on GLP-1. However, 48 h lipotoxic culture compromised both GIP (p < 0.05 to p < 0.001) and GLP-1 (p < 0.05 to p < 0.01) insulin-releasing actions. Glucolipotoxic culture (18 h) completely annulled the insulinotropic action of GIP, whereas GLP-1 effects were similar to control. However, when glucolipotoxic culture was extended to 48 h, both GIP- and GLP-1-mediated effects were (p < 0.05 to p < 0.001) impaired. Assessment of cell viability, number and insulin content revealed detrimental (p < 0.05 to p < 0.001) effects under all culture conditions, barring 18 h glucotoxic and lipotoxic culture. Finally, GIP-R gene and protein expression was increased (p < 0.05 to p < 0.01) under glucotoxic culture, with decreased (p < 0.05 to p < 0.001) expression following glucolipotoxic culture. GLP-1-R gene expression followed a similar trend, but protein levels were generally reduced under all culture conditions. CONCLUSION: The results indicate that impaired insulinotropic response to GIP and GLP-1 under diabetic milieu involves mechanisms beyond simple expression of respective receptors.