Effect of Diluents on the Extraction of Mercury(II) by n-Butyl Acetate

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Initiation of coconut cell suspension culture from shoot meristem derived embryogenic calli: A preliminary study

An attempt was made to establish highly competent embryogenic cell suspension culture in coconut, a species recalcitrant to in vitro culture. Embryogenic calli were initiated from shoot meristem explants of coconut. Y3 medium supplemented with 2.4-D (4.5 μM) and glutamine (34.2 μM) was found to be the best medium to initiate cell suspension. Growth evaluation was done by packed cell volume (PCV) and it was found that maximum growth volume of 9.9% was reached at 200 days of culture initiation. About 52% of viable cells were detected through fluorescent microscopy. Cell aggregation was noticed in Y3 medium supplemented with glutamine (34.2 μM), malt extract (100mg/l), biotin (40.9 μM) and kinetin (9.3 μM), but further progress could not be achieved. It was also observed that embryogenic calli were not of a friable type, but were associated with densely aggregated cells. Because of its hard nature, we were unsuccessful to obtain high quality cell suspension

A comparative study of 0.25% levobupivacaine and 0.25% levobupivacaine with dexmedetomidine in ultrasound-guided transverse abdominis plane block for post-operative analgesia in infraumbilical surgeries

Background: Transversus abdominis plane (TAP) block delivers excellent analgesia with few side effects. Previous research suggests that the efficacy and duration of the block can be increased by adding adjuvants such as dexmedetomidine to the local anesthetics. Aims and Objectives: To compare the post-operative analgesic effectiveness of 0.25% levobupivacaine and 0.25% levobupivacaine with dexmedetomidine 1 μg/kg in US-guided TAP block in infraumbilical surgery patients. Materials and Methods: Ultrasound-guided TAP block was given to sixty patients. Patients consented for infraumbilical surgery, and patients were randomly assigned to two groups: Group L received 20 mL of 0.25% levobupivacaine alone and Group LD received 20 mL of 0.25% levobupivacaine with dexmedetomidine 1 μg/kg. The efficacy of analgesia was measured in terms of degree and duration of analgesia; the post-operative pain was evaluated using a visual analog scale (VAS). The Chi-square test and Student’s t-test were used for statistical analysis. Results: Result shows that there is no statistically significant difference in gender, age group, weight, height, BMI, and type of surgery between groups, with a P=0.40, 0.83, 0.37, 0.59, and 0.93, respectively. In addition, there is no statistically significant difference in the duration of surgery between the groups (P=0.63). However, it was observed statistically significant differences in the onset of analgesia requirement, duration of effect of analgesia, and the total anesthesia consumption between the experimental groups with a P=0.001, 0.001, and 0.001, respectively. No significant difference in VAS was observed initially but was significant in later hours. Conclusion: Adding dexmedetomidine to 0.25% levobupivacaine enhanced the efficacy of the block and duration of post-operative analgesia compared to 0.25% levobupivacaine alone

A rocket-borne Langmuir probe response to continuous and pulsed sweep modes

Nightime ionospheric electron density and temperature are measured using a rocket-borne Langmuir probe (LP) launched on board a SONDA III rocket from the Brazilian equatorial rocket launching station in Alcantara-MA, at 23:51 hrs (LT) on May 31, 1992. A sweep voltage varying between -IV and +2.5V is applied to the spherical LP sensor alternately in continuous and pulsed modes. In the continuous mode the effect of contamination of the sensor surface on the current collected by the sensor is clearly seen in the current-voltage characteristics and thereby on the electron temperature estimated, while this effect is practically absent in the pulsed mode operation. An electron temperature profile estimated from the LP data is compared with the IRI90 model profile.Material digitalizado en SEDICI gracias a la colaboración de la Facultad de Ciencias Astronómicas y Geofísicas (UNLP).Asociación Argentina de Geofísicos y Geodesta

Impact of calcium on salivary α-amylase activity, starch paste apparent viscosity and thickness perception

Thickness perception of starch-thickened products during eating has been linked to starch viscosity and salivary amylase activity. Calcium is an essential cofactor for α-amylase and there is anecdotal evidence that adding extra calcium affects amylase activity in processes like mashing of beer. The aims of this paper were to (1) investigate the role of salivary calcium on α-amylase activity and (2) to measure the effect of calcium concentration on apparent viscosity and thickness perception when interacting with salivary α-amylase in starch-based samples. α-Amylase activity in saliva samples from 28 people was assessed using a typical starch pasting cycle (up to 95 °C). The activity of the enzyme (as measured by the change in starch apparent viscosity) was maintained by the presence of calcium, probably by protecting the enzyme from heat denaturation. Enhancement of α-amylase activity by calcium at 37 °C was also observed although to a smaller extent. Sensory analysis showed a general trend of decreased thickness perception in the presence of calcium, but the result was only significant for one pair of samples, suggesting a limited impact of calcium enhanced enzyme activity on perceived thickness

Visualisation of stabilising particles at the gas solid interface of metal foams

In this article, we demonstrate a technique to visualise the stabilising particles at the gas solid interface of metal foams by employing metallographic etching. This technique is easy to perform and can be applied on a relatively large sample size. The particles present at the gas solid interface of five different types of foams were investigated. Information on the type of particles and the particle coverage could be obtained from this stud