Eksperimentalno ispitivanje svojstava crvene banane tijekom sušenja u solarnoj sušari s jednostrukim nagibom i prirodnom ili prisilnom konvekcijom

Research background. Traditionally, open sun drying method serves to dry the products for long time preservation. Solar drying is also employed to minimise the drying time to achieve the required moisture content. This method inherently contains complex heat and mass transfer mechanisms, which makes difficult to describe drying kinetics at the micro level. Experimental approach. In this paper, research is carried out to investigate the drying of 5 mm thick slices of red banana (Musa acuminata ’Red Dacca’) in a single slope solar dryer based on natural and forced convection. Based on the experiments, a new semi-empirical thin layer drying kinetics is proposed and compared with other existing models. The proposed model with the correlation coefficient (R2) of 0.997 is in very good agreement with other well-known models. Based on the model, we calculated the moisture diffusivity and activation energy of the red banana drying process. Results and conclusions. It was found that the moisture diffusivity of the red banana samples was in the range 0.87-1.56·10-9 m2/s for natural convection solar drying and 0.84-2.61·10-8 m2/s for forced convection solar drying. The activation energy of the red banana varied from 24.58 to 45.20 kJ/mol for passive and 22.56 to 35.49 kJ/mol for active drying. Besides, we carried out energy and exergy analyses of red banana in the dryers and found that the average exergy losses in the forced and natural convections were 16.1 and 6.63 kJ/kg and the average exergic efficiency of the natural and forced convection dryers was 57.7 and 70.9%, respectively. Novelty and scientific contribution. A single slope direct solar dryer was designed and built to maintain the desired temperature for a specified period in both natural and forced convection mode. A novel drying kinetics model with higher correlation coefficient (R2) than the other drying kinetic models is proposed for the preservation of red bananas.Pozadina istraživanja. Sušenje na suncu se tradicionalno primjenjuje za dugotrajno očuvanje prehrambenih proizvoda. Također se koristi za postizanje željenog udjela vlage u proizvodu u što kraćem vremenu. Ova metoda neizostavno obuhvaća složene mehanizme prijenosa temperature i mase, zbog čega je teško opisati kinetiku sušenja u samom uzorku. Eksperimentalni pristup. U ovom je radu ispitano sušenje kriški crvene banane (Musa acuminata „Red Dacca“) debljine 5 mm u solarnoj sušari s jednostrukim nagibom i prisilnom ili prirodnom konvekcijom. Na osnovi rezultata pokusa predložen je novi, djelomično empirijski model za opisivanje kinetike sušenja u tankom sloju uzorka, te je uspoređen s postojećim modelima. Predloženi je model, s koeficijentom korelacije (R2) od 0.997, bio u skladu s drugim dobro poznatim modelima. Na osnovi novog modela izračunali smo efektivnu difuzivnost vlage i energiju aktivacije sušenja uzoraka crvene banane. Rezultati i zaključci. Rezultati pokazuju da je efektivna difuzivnost vlage u uzorcima crvene banane sušenim prirodnom konvekcijom bila 0,87−1,56·10-9 m2/s, a onih sušenih prisilnom konvekcijom 0,84−2,61·10-8 m2/s. Energija aktivacije varirala je od 24,58 do 45,20 kJ/mol tjekom pasivnog, te od 22,56 do 35,49 kJ/mol tijekom aktivnog sušenja. Osim toga, utvrđeno je da je prosječni eksergijski gubitak tijekom sušenja crvene banane u solarnoj sušari prisilnom konvekcijom bio 16,1 kJ/kg, a prirodnom konvekcijom 6,63 kJ/kg, dok je prosječni eksergijski učinak bio 57,7 %, odnosno 70,9 %. Novina i znanstveni doprinos. Solarna sušara s jednostrukim nagibom dizajnirana je s ciljem da zadrži željenu temperaturu tijekom definiranog perioda u oba načina sušenja: prirodnom ili prisilnom konvekcijom. Predložen je novi kinetički model sušenja s većim koeficijentom korelacije (R2) nego u ostalim modelima sušenja, a sa svrhom produljenja trajnosti crvenih banana

A Comparative study of 0.25% Bupivacaine and 0.25% Ropivacaine through Caudal Block for Paediatric Sub-Umbilical Surgeries

INTRODUCTION: The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage”. In children, even the definition of pain has been debated. In fact, pain experienced by infants and children often goes unrecognized or even neglected. Research over the past two decades has provided incontrovertible evidence that not only do neonates experience pain but also that unrelieved pain has adverse long-term consequences, including harmful neuroendocrine responses, disrupted eating and sleep cycles, and increased pain perception during subsequent painful experiences. Pain management is an essential component of care provided by paediatric anesthesiologists. Regional anaesthesia plays an important role in providing pain relief both in the intra-operative and postoperative periods in paediatrics. Caudal epidural anaesthesia is the most commonly practiced regional technique in children. The practice of placing a caudal block before incision in general anaesthesia results in reduced inhaled concentrations of volatile anesthetics intraoperatively. Local anaesthetics are commonly used either alone or with additives through the caudal route but the motor block produced may be a cause of distress to children in the postoperative period. Bupivacaine is a long-acting amide local anaesthetic that has provided reliable anaesthesia and analgesia with differential motorsensory blockade for more than 40 years. But, toxicity due to accidental intravascular or intrathecal injections of bupivacaine resulting in severe neurological, cardiovascular depression even leading to death prompted studies on the mechanism of the cardiotoxic effects of local anaesthetics and search for drugs with less cardiotoxicity. Bupivacaine is commercially available as racemic mixture of R- and S- enantiomers. It has been shown that block of the inactivated state of the cardiac sodium and potassium channels is stereoselective, with R-bupivacaine being more potent than S-bupivacaine. In response to the problem of increased cardiac toxicity of racemic mixtures of bupivacaine, single enantiomers were developed and Ropivacaine is the first local anaesthetic to be prepared as a pure S-enantiomer. Studies have shown that ropivacaine is less cardio and neurotoxic than bupivacaine. The sensory block provided by ropivacaine is similar to that produced by an equivalent dose of bupivacaine in extradural and peripheral nerve block whereas the motor block produced by ropivacaine is slower in onset, less intense and shorter in duration than bupivacaine. These features combined with decreased cardiovascular and neurological toxicity make ropivacaine very useful in paediatric practice especially for day case surgery which is increasing in frequency. Hence, this study was undertaken to compare the effectiveness of ropivacaine with bupivacaine for caudal anaesthesia in children. AIM OF THE STUDY: To compare 0.25% Ropivacaine and 0.25% Bupivacaine, given in a volume of 0.75ml/kg through a single Presurgical Caudal block in children aged 3-8 years undergoing sub-umbilical procedures in terms of the Quality and Duration of Analgesia, Motor and Sensory block. MATERIALS AND METHODS: This was a Prospective Double blinded Randomized Comparative Study conducted in Government Stanley Hospital, Chennai from April 2010 to September 2010. After obtaining clearance from the Institutional Ethics Committee of the Stanley Medical College, Chennai - 1, the study was explained in detail to the parents and written Informed Consent was obtained from them. Sixty children satisfying the selection criteria were randomized by computer generated randomization table into two groups of thirty each – Group B and Group R. The randomization sequence was prepared in double-blinded cancelled manner. The study solution was prepared by a final year post-graduate student who was not associated with the study. The caudal block was performed by an assistant professor whereas the observations were done by the author. The study blinding was broken after the statistical analysis. The children in group B received 0.75ml/kg of 0.25% Bupivacaine (0.5% solution diluted in equal volumes of distilled water) whereas those in group R received 0.75ml/kg of 0.25% Ropivacaine (0.5% solution diluted in equal volumes of distilled water) through the caudal route. CRITERIA FOR PATIENT SELECTION: The criteria for including the children in the study were: 1. Age 3-8 years, 2. Male or Female, 3. ASA I or II physical status, 4. Elective lower abdominal or urologic surgeries like Herniotomy, Orchidopexy, Processus vaginalis sac ligation (PVSL), Circumcision and Urethroplasty. Exclusion Criteria: The children with the following problems were excluded from the study: 1. Local infection in the Caudal region, 2. Pre-existing Neuromuscular disease, 3. Congenital anomaly of the lower back, 4. Mental retardation, Delayed development, 5. Bleeding diathesis. MATERIALS: The materials that were used for the study include 1. 22G Hypodermic needle, 2. 0.25% Bupivacaine and 0.25% Ropivacaine, 3. Appropriate size intravenous canulae and I.V. fluids, 4. Drugs for General Anaesthesia, 5. Appropriate size Endotracheal tubes, 6. Other Airway equipments, 7. Paediatric Breathing Circuit, 8. Monitors, Working Suction, 9. All Emergency drugs. METHODS: The children were fasted for 6 hours for solids and 2 hours for clear liquids. All children were premedicated with Intranasal Midazolam 0.2mg/kg68 15-20 min before surgery. They were brought into the operation theatre and intravenous access was secured with appropriate size intravenous canula. Maintenance infusion was started with Isolyte-P (4-2-1 rule) 69 and Inj. Atropine 0.02mg/kg i.v. was given. Standard Monitors like Pulse Oximeter, Blood pressure, ECG, Temperature probe, Precordial stethoscope were placed and baseline values recorded. Then the children were pre-oxygenated with 100%O2 for 3 minutes and induced with Inj. Propofol 2.5mg/kg i.v. After administering Inj. Atracurium 0.5 mg/kg i.v., the children were mask ventilated with N2O:O2 (3:3) and 2% Sevoflurane mixture for 3 minutes. Under direct laryngoscopy with the appropriate size laryngoscope blade, orotracheal intubation was performed with the appropriate size endotracheal tube and the tube position confirmed by capnography and tube secured. Statistical Analysis: Data was expressed as mean ± standard deviation. Quantitative analysis was compared with Independent sample student`s t-test for continuous variables; Chi-square test with Yates correction was used for discrete variables like sex, types of surgery. When using the above statistical tests to compare the mean among the two groups, a p-value of less than or equal to 0.05 was taken as significant. All analyses were done using SPSS version 11.5 statistical software. All values were rounded off to a maximum of two decimals. SUMMARY: Bupivacaine is the most frequently used local anaesthetic for caudal anaesthesia in children that provides reliable and long-lasting anaesthesia and analgesia. Ropivacaine provides pain relief similar to bupivacaine with less motor blockade and being a pure S-enantiomer is less cardiotoxic than the latter. The aim of the study was to compare Caudal Ropivacaine 0.25% and caudal Bupivacaine 0.25% in terms of the quality and duration of analgesia, motor and sensory block for sub-umbilical surgeries. In a double-blinded comparative study, 60 children aged 3-8 years of ASA I or II physical status were randomly allocated to receive a single presurgical caudal injection of 0.75ml/kg of either 0.25% Ropivacaine (Group R) or 0.25% Bupivacaine (Group B) after induction of general anaesthesia. Apart from monitoring the vital parameters, all children were assessed for postoperative analgesia by Hannallah pain scale and for motor blockade by Motor power score. The time for full sensory recovery was also observed. The groups were comparable for age, sex, weight, height, vital signs, duration and type of surgery. The quality and duration of postoperative pain relief did not differ between the two groups (338.83 ± 44.75 min in group R Vs 346.67 ± 51.06 min in group B). The motor blockade was significantly less in ropivacaine group than in bupivacaine group with quicker motor recovery recorded in group R(113.50 ± 10.18 min) than group B(128.50 ± 17.48 min) with a P<0.001. The time for full sensory recovery was similar for both the groups (77.50 ± 2.67 min in group R vs 80.00 ± 7.19 min in group B). Postoperative vitals were stable in all the children and the time to first micturition did not differ between the two groups (326.88 ± 41.88 min in R vs 330.00 ± 32.62 min in B). No adverse events occurred during the study. Ropivacaine is a safe and effective local anaesthetic for paediatric caudal anaesthesia. Ropivacaine 0.25% 0.75ml/kg provided good quality and adequate duration of analgesia similar to bupivacaine in equal volumes and concentration when administered for caudal block for subumbilical surgeries. Ropivacaine produced significantly faster motor recovery than bupivacaine giving a distinct advantage over the latter by allowing the children to be discharged earlier. CONCLUSION: In conclusion, Caudal Ropivacaine 0.25%, 0.75ml/kg provided reliable and long lasting analgesia similar to 0.75ml/kg of 0.25% Bupivacaine in children undergoing sub-umbilical surgeries. Ropivacaine caused less motor blockade than bupivacaine with similar time for sensory recovery. These along with the lower intrinsic toxicity of ropivacaine make it an effective and safe drug for day case surgery in paediatric patients

Comparison of Whole-body FDG-PET to Bone Scan for Detection of Bone Metastases in Patients with a New Diagnosis of Non-Small Cell Lung Cancer

Objective: In patients with lung cancer, whole-body 2-deoxy-2-[18F]fluoro-D-glucose with positron-emission tomography (FDG-PET) scan and bone scintigraphy are common staging studies, both with the ability to detect osseous metastasis. There is some evidence that PET scan is superior to bone scan and that bone scan can be replaced by PET scan. The purpose of this study was to compare the test characteristics and agreement of FDG-PET to bone scintigraphy for the detection of bony metastases in the staging of patients with newly diagnosed lung cancer. Subjects and Methods: We queried the tumor registry and nuclear medicine database at Duke University Medical Center to identify all patients between July 1998 and August 2002 with a new diagnosis of lung cancer, FDG-PET scan, and a bone scan prior to therapy. We retrospectively reviewed these patients' radiologic reports and entered them into a database. We used specific clinical criteria to confirm bone metastases, integrating all available clinical information. We then calculated the sensitivity, specificity, and likelihood ratios for each study. Results: Two hundred and fifty-seven patients fulfilled the entrance criteria. One hundred and four patients (40%) presented with stage IV disease, and we confirmed bone metastases in 57 (22%) patients. We calculated the sensitivity values of PET and bone scan as 91% and 63-75%, and specificity values as 96% and 92-95%, respectively. Likelihood ratios of positive PET and bone scans were greater than 20. Likelihood ratios of negative PET and bone scans were 0.08 and 0.16, respectively. The likelihood ratio of equivocal bone scans was 3.5. The weighted-kappa statistic suggested moderate agreement between the two modalities (Kw = 0.510, 95% CI, 0.402- 0.618). Elimination of bone scan in this cohort would have resulted in 7 (3%) of 257 patients with false positive PET results for bone metastasis, but in no case would patient management have been adversely affected. Similarly, 5 (1%) of 257 patients with bone metastases had false negative PET results, but in all cases there was other radiographic evidence of extrathoracic metastasis and Stage N disease by CT scan or PET. Conclusions: The use of both whole-body PET and bone scintigraphy as initial staging studies in lung cancer patients may provide redundant information about the presence of bony metastases. The improvement in accuracy and sensitivity with PET suggests bone scan could potentially be eliminated from the staging evaluation at presentation, but these results are limited by sub-optimal study design. We recommend a prospective trial with appropriate verification of bony metastases to confirm these results.Master of Public Healt

Effects of impurities on crystal growth processes

Ph.DDOCTOR OF PHILOSOPH

Socio-economic Impact Assessment of Livelihood Security in Agriculture, Animal Husbandry and Aquaculture on the Tsunami-hit Lands of Andaman

Indian subcontinent is highly vulnerable to major natural disasters such as earthquakes, cyclones, floods, droughts, landslides and bushfires. Tsunami, which is a recent addition to this list, had occurred in the early morning of 26th December 2004, after a massive earthquake of 9.2 magnitude on the Richter scale in Andaman & Nicobar islands, resulting in the submergence of large area of farmland, and subsequent drying up of water bodies. It caused moisture stress for the standing crops, livestock and fisheries and affected the livelihood of the people to a large extent. In this context, the present study has been carried out to make the socio-economic impact assessment of livelihood security in agriculture, animal husbandry and aquaculture on the tsunami-hit lands of Andaman. Data have been collected from 150 sample respondents and the survey has been conducted for two periods, pre-tsunami and post-tsunami. The results have indicated that tsunami has ravaged the households, standing crops, farm inputs such as seed, feed and implements, livestock and poultry population, their sheds, fish ponds, etc., thereby affecting the basic livelihood security of the people in Andaman. The rehabilitation measures taken by the government and NGOs have improved their livelihoods by reviving agriculture considerably in the subsequent years and by creating employment opportunities in various farm and non-farm activities. The paper has suggested creating profitable livelihood security to vulnerable sections of the society in the existing socio-economic penury with holistic intervention of the community, government and NGOs.Agricultural and Food Policy,

Wheat Production in India: Trends and Prospects

Trends in Indian wheat production before and after the inception of the All India Coordinated Research Project (AICRP) on wheat have been analyzed to show its significant progress over the years. A brief intercountry comparison of productivity, production and area coupled with regional comparison within India has been attempted to give an idea about the contribution of country and regions, respectively, for global and national food security. The milestones in Indian wheat programme and research outcomes were highlighted post-AICRP along with the vision and strategies set for 2050 against diverse production challenges. Regional disparities, zone-wise production constraints and research programmes for achieving the set production target were briefed. The chapter concludes with possible interventions in strengthening the complete wheat value chain for ensuring food security for the future generation

Analyzing the Information Sharing Practices and Barriers in Supply Chain of Automotive Industries

Information sharing and technology remain one of the key factors of coordination amongst the parties in a supply chain. Supply chain efficiency is highly important as today�s competition is no longer between companies, but between supply chains. Information sharing can increase supply chain efficiency by reducing inventories and smoothing the production. The purpose of this study is to assess the status of the supply chain information sharing practices in Indian automotive industries. This study is focused on identifying the types of information shared, determining the level of information sharing , usage of Information Technology (IT) tools and identifying the barriers of information sharing. Data for this study is collected from the respondents of Original Equipment Manufacturer (OEM), Tier 1, Tier 2 and Tier 3 Indian automobile industries. Frequency analysis is employed to derive the results from the survey

Periodontitis as a risk factor for preterm labour and low birth weight among pregnant women attending a tertiary care teaching hospital

Background: Preterm birth is the single most important factor affecting perinatal outcome in terms of both morbidity and mortality. Chronic infections in mother are being implicated as a cause of preterm labour. The objective of this study was to find out a causal association between periodontitis and preterm labour or low birth weight. It was a Case- Control Study. This study was conducted in Mahatma Gandhi Medical College and Research Institute, Puducherry between February 2013 and June 2014.Methods: A total of 200 women were included in the study with 100 women in each group (cases and controls). Cases included women who had spontaneous preterm labour or threatened PTL (gestational age 28- 36 weeks) or women who had delivered a baby with the birth weight being less than 2.5 kg. Controls were patients who had a normal labour with the gestational age of more than 37 weeks with birth weight of the baby more than 2.5 kg. Periodontal examination was done for both cases and controls. Periodontal factors like Plaque Index (PI), bleeding Index (SBI), Probing pocket depth (PD) and Clinical attachment level (CAL) were examined for both groups. Student t test, Chi-square and Fisher Exact has been used for statistical analysis.Results: In the present study, plaque index and bleeding index was significantly more in cases than controls with a p value of 0.009 and 0.035 respectively. Evidence of periodontitis was seen in 86% of cases and 76% of controls respectively which was also statistically significant with a p value of 0.071.Moderate periodontitis was found in significant number cases and was statistically significant with a P value of &lt;0.001.Conclusions: This suggests that there exists an association between moderate periodontitis and preterm labour and low birth weight

IEEHR: Improved Energy Efficient Honeycomb based Routing in MANET for Improving Network Performance and Longevity

In present scenario, efficient energy conservation has been the greatest focus in Mobile Adhoc Networks (MANETs). Typically, the energy consumption rate of dense networks is to be reduced by proper topological management. Honeycomb based model is an efficient parallel computing technique, which can manage the topological structures in a promising manner.&nbsp; Moreover, discovering optimal routes in MANET is the most significant task, to be considered with energy efficiency. With that motive, this paper presents a model called Improved Energy Efficient Honeycomb based Routing (IEEHR) in MANET. The model combines the Honeycomb based area coverage with Location-Aided Routing (LAR), thereby reducing the broadcasting range during the process of path finding. In addition to optimal routing, energy has to be effectively utilized in MANET, since the mobile nodes have energy constraints. When the energy is effectively consumed in a network, the network performance and the network longevity will be increased in respective manner. Here, more amount of energy is preserved during the sleeping state of the mobile nodes, which are further consumed during the process of optimal routing. The designed model has been implemented and analyzed with NS-2 Network Simulator based on the performance factors such as Energy Efficiency, Transmission Delay, Packet Delivery Ratio and Network Lifetime

Assessment of Solar Dryer Performance for Drying Different Food Materials: A Comprehensive Review

Studying crucial drying parameters, such as activation energy and moisture diffusivity, offers valuable insights for optimizing food safety. Accurate predictions and simulations through mathematical thin-layer models aid in designing, controlling, and optimizing drying operations for various food items. Solar drying presents a viable and eco-friendly solution for food preservation. This chapter critically evaluates solar drying performance for various vegetables, fruits, marine products, and other commodities, providing comprehensive insights into its efficiency. According to the literature, the moisture diffusivity (m2/s) for vegetables has been reported to be within the range of 2.01 × 10−10–1.935 × 10−8. For fruits, the moisture diffusivity varies between 1.33 × 10−10 and 6.98 × 10−9. In the case of marine food products, the range is found to be 2.8 × 10−8–3.408 × 10−7, while for other commodities, it falls between 1.79 × 10−9 and 1.061 × 10−7. The activation energy (kJ/mol) for vegetables has been observed to fall within the range of 24.81–47.19. Similarly, for fruits, the activation energy varies between 2.56 and 45.20. Notably, Ginger demonstrates an activation energy of 35.675 kJ/mol. Experimental results showed that lower activation energy and higher moisture diffusivity accelerate dehydration