PROCESSING AND STORAGE OF CARBONATED GUAVA BEVERAGE

Guava cv.'Allahabad Safeda'was crushed and treated with pectic enzymes at 0.1% concentration (w/v), incubated for 1 h at 40–50C and the liquefied juice having 10.8 Brix and 0. 65% acidity was used for carbonation. The juice was converted into sugar syrup base having 40% guava juice at 40 Brix and 1% acidity. After dosing 50 ml of it into a glass bottle (200ml capacity) filled with chilled (4-6C) carbonated water at 80 psi pressure of CO₂ gas, the bottle was sealed with crown cork and heat processed at 60C for 30 min. The carbonated guava beverage could be stored for 3 months at room (23-41C) and low (3-5C) temperatures and was found acceptable with respect to color, flavor and overall quality. Heat processing improved the flavor of the carbonated guava beverage, and the beverage contained no detectible microbes.     

Reliability analysis of universal joint of a compliant platform

The paper describes a methodology for computation of fatigue reliability of universal joint in an articulated offshore tower. Failure criteria were formulated using the conventional Palmgren‐Miner rule (S‐N curve approach) and the fracture mechanics (F‐M) principle. The dynamic analysis of double hinged articulated tower under wind and waves is carried out in time domain. The response histories of hinge shear stresses are employed for the reliability analysis. Advanced first‐order reliability method and Monte Carlo simulation method were used to estimate the reliability. Various parametric studies were carried out, which yield important information for the reliability based design. The S‐N curve approach yields a significantly conservative estimate of probability of failure when compared to the F‐M approach.     

OPTIMIZATION OF MARINE FISH DRYING USING SOLAR TUNNEL DRYER

Studies were conducted to optimize fish-drying process in a Hohenheim-type solar tunnel dryer to produce safe and high quality dried fish products. Five commercially important tropical marine fish species in the Bay of Bengal such as silver jew fish, Bombay duck, big-eye tuna, Chinese pomfret and ribbon fish were used and drying was performed at 45 to 50 and 50 to 55C temperature ranges. Moisture content of the fish samples reached 16% after 36 and 32 h of drying at temperature ranges of 45 to 50 and 50 to 55C, respectively. Products produced at 45 to 50C were found to be excellent on the basis of flavor, color and texture. Their rehydration ability ranged from 65 to 80% with minimum in big-eye tuna and maximum in silver jew fish. Values of total volatile base, peroxide and aerobic plate count of all the final dried products were within the acceptable limit.

PRACTICAL APPLICATIONS

In this experiment, we optimized the drying process in a Hohenheim-type solar tunnel dryer, constructed using locally available materials, for several commercially important marine fish species in the Bay of Bengal over a wide range of temperature, humidity and moisture content. The data obtained in this study are now successfully used for large-scale production of dried fish of high quality, providing better market price for its producers as well as greater acceptability to the consumers. We also developed another low cost solar tunnel dryer using bamboo, hemp, canvas, rope and polythene sheets, which became very popular among small-scale dry fish producers in the coastal areas of Bangladesh.     

MOLD INHIBITION IN TORTILLA BY DIMETHYL FUMARATE

Nine batches of tortilla containing 0, 0.05, 0.1., 0.2 and 0.4 g of calcium propionate or dimethyl fumarate per 100 g corn flour were prepared. The tortillas were individually packaged in polyethylene bags, stored at room temperature and observed daily for visible signs of mold growth. Samples from each batch were also subjected to the determination of moisture and water activity. The mold-free shelf-lives of tortillas containing calcium propionate ranged from 2–5 days and those of tortillas containing dimethyl fumarate ranged from 2–11 days.     

Effect of Trans Fatty Acids on Protein Utilization and Serum Cholesterol

Rats were fed PER diets containing various proportions of cis and trans fatty acids as triolein, trielaidin, soybean oil (SO) or hydrogenated SO at 7.8% by weight of the diet. Additional rats were fed SO or hydrogenated SO at 20.1% of the diet. The PER, although in the normal range for casein, was significantly (P < 0.01) lower in rats fed trielaidin. Food consumption and weight gains were slightly greater in trans-fed than cis-fed rats. The former had greater fecal fat excretion than the latter; serum cholesterol levels of the former were lower with the 7.8% but not the 20.1% fat diet.     

Dehydration of potato

Drying behaviour of potato in a natural convection, solar dryer was investigated. In drying experiments conducted at low air velocity, as found in the solar dryer, it was shown that air flow conditions are of critical importance for drying behaviour. As a result of the presence of extensive, external mass transport resistances in deep bed drying, the air flow behaviour of the bed was more important than the drying behaviour of the single pieces. Thus, for deep bed solar drying, 10x10 mm french cut potatoes dried faster than 5 mm slices. (This result was opposite to that found for drying in thin layers). Drying time was noted to increase less rapidly than bed depth increased, so overall dryer productivity increased with increasing bed depth, within the constraint that drying be completable in 1 day.     

Insight into 5-aminolevulinic acid-induced modulation of cellular antioxidant metabolism to confer salinity and drought tolerance in maize

The current study investigated the comparative oxidative damage in two maize seedlings induced by saline, drought, and combined stress and the ameliorative role of two different doses (20 and 80 µM) of 5-aminolevulinic acid (ALA) against the above-mentioned stresses. Hydroponically grown 10-day-old maize (Zea mays, var. BARI Hybrid Maize-7 (BHM-7) and BARI Hybrid Maize-9 (BHM-9)) seedlings were exposed to 12 dS/m of saline solution, 200 mM mannitol-induced drought stress alone and their combined stress for 7 days. Result revealed that individual stresses retard the plant growth to some degrees; however, their combined stress has more detrimental effects, which might be correlated with lipid peroxidation (MDA)-induced oxidative stress in seedlings, enhanced Na⁺ /K⁺ ratio, and augmented generation of superoxide (O₂^•− ) and hydrogen peroxide (H₂O₂). In contrast, exogenous ALA supplementation at 20 µM concentration markedly recovered from chlorosis and growth inhibition, substantially scavenged reactive oxygen species (ROS) and MDA by preserving ionhomeostasis and relaxing oxidative stress; also, by boosting catalase (CAT) and glutathione S-transferase (GST), and exclusively via depressing the activity of lipoxygenase (LOX) antioxidant enzyme. On the contrary, 80 µM ALA made things worse; nevertheless, higher activities shown by other antioxidant enzymes; like, superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase (POD), and glutathione peroxidase (GPX), which were related to lessen the oxidative damage by highly produced O₂^•− and H₂O₂ under combined stress. Non-denaturing gel electrophoresis was done for further confirmation. However, ALA importantly increased the photosynthetic pigment contents in both genotypes irrespective of doses. Nevertheless, GST might have assisted the plants to escape from the herbicidal effect by detoxification. However, in the combined stress condition, high ALA concentration may have some positive role to play. Our findings also showed that BHM-9 performed better than BHM-7. Therefore, ALA at lower concentration was effective for single stress of saline and drought, while higher concentration can improve plant survival under combined stress.     

Use of Impella cardiac axial flow pump for cardiogenic shock (A newer alternative)–How good is the evidence?

The adverse outcomes of a ventricular heart failure (left, right or biventricular) caused by cardiogenic shock are aggravated by lung oedema and organ mal perfusion. Despite advances in medical sciences, revascularisation and mechanical hemodynamic support have proved ineffective in reducing the mortality rate in such patients. A thorough study of the data available about cardio-vascular diseases reveals that the application of conventional methods of treatment are least helpful to practically restore normal functions of heart when it experiences end-stage systolic ventricular failure. Thus, to overcome the challenges and find alternatives to address this issue, percutaneous ventricular support devices/machines were designed and successfully introduced. These devices have revolutionized the treatment of ventricular heart failures and are now in use all over the world. In this review paper a newer mechanical circulatory support (MCS) device, Impella, has been discussed and compared with a few other devices like (Intra-aortic Balloon Pump (IABP), Extracorporeal Circulation (ECLS) and Veno-arterial Extracorporeal Membrane Oxygenation (VA-ECMO). This article studies the challenges being faced during the treatment of cardiogenic shock, and thoroughly discusses the use and effectiveness of Impella Cardiac Axial Pump in each emergency. It can be said that mechanical circulatory support (MCS) device use during percutaneous coronary intervention (PCI) should be individualized based on multiple factors with a recommended use in patients with the greatest potential benefit and a relatively low risk of device-related complications. The current literature suggests that the outcomes of use of Impella and other mechanical circulatory support devices like IABP and VA-ECMO are comparable. Though there seem to be a few advantages of Impella over the others, sufficiently powered, multi-centric, randomised control trials are needed to establish its superiority.     

A comparative study on heat dissipation, morphological and magnetic properties of hyperthermia suitable nanoparticles prepared by co-precipitation and hydrothermal methods

Magnetite (Fe₃O₄) nanoparticles were prepared by co-precipitation and hydrothermal methods and their phase transfer was done successfully to compare their performances in different aspects. Synthesized nanoparticles were characterized for XRD, FE–SEM, TEM, UV-Vis absorption (reflectance) spectra, magnetic hysteresis loops and a.c. magnetic field induced hyperthermia. The magnetic nanoparticles prepared by the co-precipitation method show superior performances in respect of heat dissipation capability, saturation of magnetization values and particle size when compared to those prepared by the hydrothermal method.