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Objective: To present this series of surgically treated tuberculum sellae meningiomas with particular regard to visual compromises Methods: A retrospective analysis was done on 28 patients (21 females) with meningiomas originating from the tuberculum sellae who underwent surgery between 2010 and 2019. The standard surgical approach of pterional craniotomy. Twelve meningiomas extended posteriorly onto the diaphragma sellae, 13 anteriorly to the planum sphenoidale, and 3 to the anterior clinoid process. 21 tumours involved the optic canal, one bilaterally. Follow up ranged from 6 to 12 months. Results: Total microscopic resection was achieved in 28 patients. Median tumour size was 3.2 cm. Postoperatively, visual acuity improved in 19 patients and deteriorated 3. Preoperative and postoperative visual acuity worsened with increasing duration of preoperative symptoms and with increasing age. Extension into the intraconal space was a negative predictor. Recurrence occurred in one cases. One patients died from causes unrelated to the tumour. Conclusions: In the majority of patients with tuberculum sellae meningiomas, total resection may be achieved through a pterional approach with minimal complications. Bang. J Neurosurgery 2020; 10(1): 39-44

The antioxidant and antimicrobial activity of the essential oil extracted from Syzygium aromaticum was investigated. Extraction of oil was carried out following the standard methodology of supercritical CO2 extraction. Antiradical and antimicrobial activity of extracted oil was studied. Chemical constituent of oil exhibited 65.3% eugenol. It was found that the extracted clove essential oil demonstrated high antioxidant contents which lead to free radical scavenging, reducing power, metal chelation and inhibition of lipid peroxidation. Shigella dysenteriae and Staphylococcus aureus showed susceptibility towards oil. Minimum Inhibitory concentration values for two tested bacteria are 3.0 and 2.5 mg/ml. Growth inhibition around well loaded with different concentration of oil further confirmed antimicrobial property. Additionally, clove essential oil also seen to be compatible to goat’s erythrocytes. Findings suggest that clove essential oil may act as therapeutic molecules against diseases caused by pathogens and free radicals.

The current study investigates the absorption kinetics of carbon dioxide (CO2) released from power plant exhaust using activated mixture of 2-amino-2-methyl-1-propanol (AMP) upgraded by piperazine (PZ). An absorption experiment of (AMP+PZ+H2O) was conducted in a wetted wall column absorber with a temperature variation of 298–313 K and CO2 partial pressure of 5–15 kPa. PZ is considered to be a rate promoter by adjustable mass proportion varying from 2 to 10 wt%, while the concentration of entire amine solution remained constant at 30 wt%. Based on the Zwitterions mechanism, an overall reaction pattern of (AMP+PZ+H2O) with CO2 was designed. Considering pseudofirst order reaction criteria, the kinetic rate factors and the overall second order rate constants were calculated. The overall rate constant (kOV) experienced a significant enhancement with a small addition of PZ into aqueous AMP solution. The observed second-order rate constants (k2, PZ) in this experimental study were 60,403, 81,925, 98,591 and 116,521 m3·kmol−1·s−1 at 298, 303, 308 and 313 K correspondingly. The experimental specific rate of absorption into (AMP+PZ+H2O) in connection with the model anticipated rate was determined with deviation of around 4.86% average absolute deviation (AAD).

Kiwi fruit (Actinidia deliciosa) (KF) is one of the best fruits available due to its large amount of nutrients. Despite its many health benefits, there are no previous reports on its preparation in other readily ingestible forms. The objective of the present study was to make a new food product from KF. The KF pulp was fortified and blended with several raw materials (such as rice flour and oat flour) using a stepwise short time addition and mixing methodology since this avoids unwanted biochemical and chemical reactions. The blended and reduced moisture KF paste was freeze-dried on a round silver coated steel plate (RSCSP), supplying the heat of sublimation using a newly designed cubic heater. The freeze-drying (FD) time was 4.5 h and the drying kinetics were studied using four established models. The effective moisture diffusivity (Deff) during FD (at 50 °C) was 1.532 x 10-6 m2/s and the activation energy (E) estimated for the FD was 28.35 kJ/mol. The freeze-dried sample was ground and placed under vacuum to reduce the weathering effects. The quality of the stored product was evaluated using the proximate analysis, physicochemical analysis and a sensory evaluation using a hedonic scale. The raw, fresh KF had a moisture content of 85.07% and the final freeze-dried product one of 3%. The carbohydrate, total sugar, protein, fat, total ash, crude fibre and vitamin C contents of the final product increased by 563%, 400%, 355%, 386%, 672%, 106%, and 117% respectively. Of the 66 panelists, the % consumer acceptances for the different attributes were: sweetness (68.18%), sourness (90.91%), saltiness (100%), bitterness (100%), flavour (95.45%), texture (77.27%) and overall acceptability (81.82%). Using conventional freeze-drying (CFD) for blended KF pulp without fortification, with the same RSCSP and the same cubic heater for sublimation, the drying time was found to be 7 h to reach the same final moisture content of 3%.

Objectives: In this study, a highly nutrient food rich in vitamins and minerals, kiwi fruit (Actinidia deliciosa), is dehydrated effectively at a faster rate keeping almost all its original properties. Methods/Analysis: A new methodology, consecutive Osmotic Dehydration (OD) and Freeze Drying (FD), was developed and applied. This technique was found to be very effective with respect to drying time, cost and quality. The OD was performed using sucrose solution at three concentrations (40°B, 55°B, and 70° B), three temperatures (40°C, 45°C, 50°C) and three time spans (2, 3 and 4 h). OD parameters were optimized by “Taguchi orthogonal design” methodology. Findings: Optimal time for OD was found to be 3 h, at 40°B, 50°C corresponding to 60.75% water loss and 9.86% solute gain. Notably, at optimal OD conditions, application of fructose solution resulted unfavorable result. In FD of osmotically dehydrated kiwi fruit, the thermal energy was supplied by an innovative Silver Coated Steel Heater (SCSH), which was found to be much more efficient (required only 2.5 h drying time) compared to an equal power conventional steel heater (SH) (required 3.82 h drying time) to achieve a final kiwi fruit moisture content ≤ 5% (w/w). At both optimal OD and FD, the drying kinetics was assessed using four models. The values of effective diffusivity (D eff ) and activation energy indicated higher energy-efficiency for SCSH compared to SH. The proximate nutritional analyses for fresh and dehydrated kiwi samples indicated very good quality of the processed product. Novelty/Improvement: The uniqueness and novelty of this research work is less drying time and almost no nutritional loss as compared with other conventional techniques.

A mathematical model depicting the influence of operating parameters on unsteady drying rate in primary freeze-drying operation for two food stuffs viz. paneer and mango has been presented. The dynamic model based on a semi-deterministic approach involving two major operating parameters, viz., radiator temperature and chamber pressure, has been validated over a chamber pressure ranging from 0.05 to 0.001 mbar and for a radiant heat source temperature ranging from 293 to 323 K keeping the physical shape of the material unaltered. The model equations proposed are free from simulation constants like the effective diffusivity and the Knudsen diffusivity which are difficult to evaluate. The surface temperature profile of the material during the course of primary freeze-drying has also been presented by applying the model equation for drying rate in the unsteady state one-dimensional energy balance equation. Experimental results fit appreciably well with the simulated data. It is expected that the model equations can be used for estimation of unsteady drying rate vis-a-vis dried layer temperature–time history for similar foodstuffs if physical properties viz. specific gravity, porosity, thermal conductivity, specific heat are known.

The absorption of dilute CO 2 into aqueous solutions of a sterically hindered amine, 2-amino-2-methyl-1-propanol (AMP), is modeled in the mechanically agitated contactor under the fast pseudo first-order reaction condition using the kinetic data for CO 2 –AMP presented elsewhere by this study group [A.K. Saha, S.S. Bandyopadhyay, A.K. Biswas, Kinetics of absorption of CO 2 into aqueous solutions of 2-amino-2-methyl-1-propanol, Chem. Eng. Sci. 50 (1995) 3587–3598.] Experimental results of absorption studies in the mechanically agitated contactor at 288 and 301.5 K over ranges of CO 2 partial pressure (5–15 kPa) and amine concentration (1–2 kmol m −3 ) are in excellent agreement with the results predicted from the numerical model, confirming the validity of the mathematical model proposed, and the kinetic data and the mechanism presented earlier by this study group for the CO 2 –AMP system [A.K. Saha, S.S. Bandyopadhyay, A.K. Biswas, Kinetics of absorption of CO 2 into aqueous solutions of 2-amino-2-methyl-1-propanol, Chem. Eng. Sci. 50 (1995) 3587–3598.] The maximum deviation between the predicted and experimental values of liquid-phase CO 2 loading with time was within 3%.