Sustainable Studies on Concrete with GGBS As a Replacement Material in Cement

The utilization of supplementary cementation materials is well accepted, since it leads to several possible improvements in the concrete composites, as well as the overall economy. The present paper is an effort to quantify the strength of ground granulated blast furnace slag (GGBS) at various replacement levels and evaluate its efficiencies in concrete. Cement with GGBS replacement has emerged as a major alternative to conventional concrete and has rapidly drawn the concrete industry attention due to its cement savings, energy savings, cost savings, environmental and socio-economic benefits. This research evaluates the strength and strength efficiency factors of hardened concrete, by partially replacing cement by various percentages of ground granulated blast furnace slag for M35 grade of concrete at different ages. From this study, it can be concluded that, since the grain size of GGBS is less than that of ordinary Portland cement, its strength at early ages is low, but it continues to gain strength over a long period. The optimum GGBFS replacement as cementation material is characterized by high compressive strength, low heat of hydration, resistance to chemical attack, better workability, good durability and cost-effectiveness

Induction of drought stress tolerance by Propiconazole and Salicylic acid in Sorghum bicolor is mediated by enhanced osmoregulation, compatible solutes and biochemical accumulation

A pot-culture experiment was carried out to estimate the ameliorating effect of Propiconazole (PCZ) and Salicylic acid (SA) on drought stressed Sorghum bicolor. The plants were subjected to 3, 6 and 9 Day Interval Drought (DID) and drought with PCZ 1 mM and SA 1 mM alone from 30, 40 and 50 Days After Sowing (DAS). One day interval irrigation was kept as control. The plant samples were collected on 60, 70 and 80 DAS then separated into root and shoots for estimate the protein, proline, amino acid (AA), glycine betaine (GB) and total sugar content. Drought stress inhibited protein content then the proline, AA, GB and total sugar contents were increased when compared to control. Plants were treated drought with PCZ and SA these parameters to a larger extent when compared to drought stressed plants. The PCZ and SA treatments increased the protein content, but decreased the proline, AA, GB and total sugar contents when compared to drought stressed plants. From the results of this investigation, it can be concluded that the application of PCZ and SA caused a partial amelioration of the adverse effects of drought stress in sorghum plants

Reverse micelles: Functionalizing, cross-linking, entrapment and applications

In the first chapter, a brief background in the formation of reverse micelles and their applications was presented, followed by the formation and applications of interfacially crossed-linked reverse micelles(ICRM) in catalysis. In the second chapter, self-assembly of proline surfactants and its application in aldol reaction were discussed. Prolinamide-functionalized surfactants catalyzed aldol reaction in a nonpolar solvent in the reverse-micelle form. The reverse micelle nanostructure creates a high local concentration of prolinamide, which catalyzes aldol reaction co-operatively. In polar DMSO, the surfactants exist as individual molecules and lose their catalytic activity. In the third chapter, hydrophilic dyes were trapped in the core of the ICRM to help understand the micropolarity of the ICRM. In the fourth chapter, the site isolation of catalysts by ICRM was demonstrated for manganese porphyrins that are known to dimerize and deactivate. ICRM-entrapped catalysts showed enhanced catalytic activity than their free counterparts. In the fifth chapter, the advantage of ICRM over uncross-linked reverse micelle and its selectivity towards hydrophilic substrates were demonstrated by trapping PtCl2(TPPTS)2 in the core of the ICRM. This catalyst was used to catalyze hydration of alkynes. Since water is a reactant and can be concentrated in the core of the ICRM, the catalyst showed enhanced catalytic activity and selectivity towards hydrophilic substrates

Propiconazole and Salicylic acid alleviate effect of drought stress in sorghum (Sorghum bicolor L. Moench) through biochemical and some physiological characters.

In this study, the protective role of propiconazole (PCZ) and salicylic acid (SA) in relation to biochemical content and some physiological parameters were investigated in drought stressed Sorghum bicolor plants. The pot culture experiment was carried out on Botanical garden, Deportment of Botany, Annamalai University.  A 30 Days After Sowing (DAS) plants were subjected to 3, 6, and 9 Days Interval Drought (DID) stress and drought with PCZ at 1 mM and drought with SA at 1 mM at 30, 40, and 50 DAS. The plants irrigated regularly in alternate day interval were kept as control. The plant samples were collected on 60, 70, and 80 DAS from all the treatments. The biochemical contents like starch and sucrose, then physiological parameter like Relative Water Content (RWC) and Electrolyte Leakage (EL) were analysed. Under the drought stress reduced starch and RWC was observed then, sucrose and EL content were increased. The drought with growth regulator treated plants starch and RWC was reduced then, sucrose and EL was increased but it was lower than that of control. Together, our findings demonstrate that, PCZ and SA is an efficient growth regulator with diversified roles that contribute to its potential alleviating effect against drought stress

Eff ect of propiconazole and salicylic acid on the growth and photosynthetic pigments in Sorghum bicolor (L.) Moench. under drought condition

The present investigations were carried out to estimate the morphological, pigments variation and ameliorating effect of propiconazole (PCZ) and salicylic acid (SA) on drought stress in sorghum (Sorghum bicolor L. Moench.) Var. CO-30. A 30 days after sowing (DAS), the plants were subjected to 3, 6, and 9 days interval drought stress and drought with PCZ at 1 mM and drought with SA at 1 mM at 30, 40, and 50 DAS. The plants irrigated regularly in alternate day interval were kept as control. The plant samples were collected on 60, 70, and 80 DAS from all the treatments. The root length, shoot length, fresh weight, dry weight, total leaf area, and photosynthetic pigment estimation was carried out in each treatment. Individual and combined drought stress with PCZ and SA treatments increased the root length when compared to control. The PCZ and SA treatments mitigated the drought stress by increasing the morphological and pigment contents and there by the way for overcoming drought stress in S. bicolar plants

Technology Education and Economic Competitiveness in Developing Countries: The Sri Lankan Experience

This paper examines the status of technology education in developing countries generally, and Sri Lanka in particular. A review of current literature reveals that science and technology are critically important for every country\u27s socio-economic development. The conceptual framework and major features of technology education that should be emphasised in developing countries are discussed. The paper also highlights some severe barriers and limitations that inhibit technology education in developing countries. It is concluded that the Sri Lankan economy requires an effective implementation of appropriate technology education, and that this implementation must begin with scientific and technological literacy at the school level. This holds true for other developing countries currently battling the myriad problems arising from technological deprivation and backwardness. The paper contends that technological education could play the role of enhancing the right kind of technological development and advancement that could over time transform the economic fortunes of, and living conditions in developing countries. Cet article examine la situation de l\u27enseignement de la technologie dans les pays en voie de développement en général et en Sri Lanka en particulier. Un compte-rendu de la littérature contemporaine révèle que les sciences et la technologie ont une importance indispensable pour le développement socio-économique de tout pays. On y discute le cadre conceptuel et les principales caractéristiques de l\u27enseignement de la technologie sur lesquels devront insister les pays en voie de développement. L\u27article met également en relief les barrières et les limitations qui entrave l\u27enseignement de la technologie dans ces pays. De là, l\u27article conclut que l\u27économie du Sri Lanka exige l\u27exécution efficace d\u27une formation technologique appropriée et que cet exécution devra commencer par une connaissance scientifique et technologique au niveau scolaire. Cela est aussi vrai pour les autres pays en voie de développement qui sont en train de lutter contre une myriade de problèmes qui proviennent de la privation et du retard technologiques. L\u27article soutient que la formation technologique pourrait jouer le rôle d\u27améliorer la forme correcte du développement et du progrès technologiques, qui pourrait dans un certain temps, transformer les fortunes économiques et les conditions de vie dans ces pays en voie de développement

Interfacial catalysis of aldol reactions by prolinamide surfactants in reverse micelles

L-Proline and their derivatives are among the most important class of organic catalysts. Three prolinamide surfactants were designed and synthesized. Although the surfactants carried identical catalytic groups, their headgroups contained different functionalities that affected their ability to self-assemble under reverse micelle conditions and hydrogen-bond with the reactants. The surfactant with a zwitterionic headgroup capable of strong aggregation was found to have the highest activity. The self-association of the surfactants played critical roles in the enhanced activity. The location of the catalytic groups at the surfactant/polar solvent interface also endowed unusual selectivity in the catalyzed aldol reactions

All-Optical Constant-Force Laser Tweezers

AbstractOptical tweezers are a powerful tool for the study of single biomolecules. Many applications require that a molecule be held under constant tension while its extension is measured. We present two schemes based on scanning-line optical tweezers to accomplish this, providing all-optical alternatives to force-clamp traps that rely on electronic feedback to maintain constant-force conditions for the molecule. In these schemes, a laser beam is rapidly scanned along a line in the focal plane of the microscope objective, effectively creating an extended one-dimensional optical potential over distances of up to 8μm. A position-independent lateral force acting on a trapped particle is created by either modulating the laser beam intensity during the scan or by using an asymmetric beam profile in the back focal plane of the microscope objective. With these techniques, forces of up to 2.69 pN have been applied over distances of up to 3.4μm with residual spring constants of <26.6fN/μm. We used these techniques in conjunction with a fast position measurement scheme to study the relaxation of λ-DNA molecules against a constant external force with submillisecond time resolution. We compare the results to predictions from the wormlike chain model

A Study of Posterior Circulation Ischemic Stroke in 80 Patients : Clinical Manifestations, Risk Factors, Imaging Studies and Outcome

INTRODUCTION : Stroke is one of the leading causes of morbidity and ranks next only to coronary artery disease and malignancy as the leading cause of mortality worldwide. At least fifty percent of neurological disorders in a general hospital are due to stroke. As remarked by a renowned neurologist, C. M. Fisher, neurology is learnt stroke by stroke. Eighty percent of stroke is ischemic; twenty percent of ischemic events involve tissue supplied by posterior circulation. The paralysis of vertebrobasilar stroke can devastating and some forms have high rates of death. Many cases of vertebrobasilar diseases remain undiagnosed or are incorrectly diagnosed. Formerly clinicians used the catchall term vertebrobasilar insufficiency to indicate a hemodynamic cause of all cases of posterior circulation ischemia. During the past fifteen years information provided by detailed clinical studies and brain imaging has revolutionized our understanding of clinical aspects, mechanism, treatment and prognosis of posterior circulation ischemic stroke. The etiology of posterior circulation ischemia has been thought to be primarily due to local arterial atherosclerosis (large artery disease) and penetrating artery disease (lacunes) However there is increasing evidence that cardiogenic embolization is more common than previously suspected and is responsible for 20 – 50% of posterior circulation strokes. The posterior circulation, unlike the intracranial portions of the anterior circulation, is prone to atherosclerosis much as other systemic arteries. In the case of one vertebral artery being occluded, collateral flow comes from the opposite vertebral artery, from muscular cervical artery branches, and from posterior communicating artery. Now with better understanding of risk factors involved in stroke the emphasis should be prevention rather than management. AIMS OF THE STUDY : 1. To evaluate the etiology in posterior circulation stroke. 2. To study the commonest mode of clinical presentation in posterior circulation ischemic stroke. 3. To evaluate the commonest anatomical area involved and the size of the infract with the help of imaging modalities (CT and MRI). 4. To assess the outcome. MATERIALS AND METHODS : This study was carried out in patients who presented with posterior circulation ischemic stroke to the medicine and neurology department of PSG Institute of Medical Sciences and Research, Coimbatore. The study was conducted during the period of January 2005 to march 2006. All patients admitted with clinical features suggestive of posterior circulation stroke were taken. All were subjected to CT scan brain. Patients with evidence of posterior circulation stroke clinically and imaging wise were taken up for the study. Inclusion Criteria: All patients with clinical features suggestive of posterior circulation stroke Imaging showing infarcts within the posterior circulation territory. Exclusion Criteria: CT evidence of showing haemorrage Patients having evidence of infarcts in other areas ie. , territory of anterior circulation, border zone infarcts. Patients on ventilator, global aphasia, in coma were excluded from studies. All the patients were evaluated in detail. A detail history was recorded with special emphasis on risk factor, mode of presentation, time interval between onset and arrival to hospital. Major risk factor included in this study are hypertension, diabetes mellitus, dyslipidemia, age sex, coronary artery disease, smoking, alcohol intake, and transient ischemic attack Special emphasis was given for clinical evaluation of cardiovascular system with regard to rhythm disturbances cardiac failure, and valvular heart disease. Detailed clinical neurological examination was done and the patients were grouped into posterior circulation stroke Blood haemogram, peripheral smear, haematocrit, blood sugar lipid profile, and renal function tests were done. Echocardiogram was done. to rule out intracavitary clots and vegetation. Imaging studies including CT, MRI and Doppler Studies were done to localize the anatomical area involved and to know the size of the area involved. Outcome was assesed according to the modified rankin scale at 30 days. DISCUSSION : Cerebrovascular disease was more common in men in the age group of >60 years. In ‘tufts posterior registry’ 52% were male and 48% were females. Smajlonc D33 studied ischemic insult in both anterior and posterior circulations and he found 18. 2% had posterior circulation stroke and he also found females and males were equally affected in posterior circulation stroke. In this study 63. 75% were males. Though the above mentioned study showed sexual equality our study showed a male preponderance. Mean age of pts in our study was 60 years which was similar to other studies. The risk factors in stroke are classified as modifiable and non modifiable. Male sex and older age are non-modifiable risk factors. Hypertension is the most common risk factor associated with stroke. In our study 52. 5% were hypertensives this was similar to the stoke study of Nizam’s Institute Hyderabad. Diabetes mellitus, hypercholesterimia, smoking, obesity, ischemic heart disease, atrial fibrillation, heamatocrit elevation are other modifiable risk factors. CONCLUSION : In my study I found that • Males were affected more than females. • Age group commonly involved was above sixty yrs. • Hypertension, diabetes and smoking contributed the major risk factors followed by cardio embolic source. • Giddiness was commenest symptom at the onset. • Most of the patients had clinical signs of cerebellum and brainstem lesions. • The territory commonly involved was mid-brain, cerebellum, thalamus, occipital and temporal lobes. • MRI was found to be more sensitive than CT in identifying brain stem lesions. • Outcome in posterior circulation stroke was found to be better than anterior circulation stroke

Effect of processing parameters on recovery of hot process virgin coconut oil and co-products utilization

Virgin coconut oil (VCO) is growing in popularity as functional food, cosmetic and pharmaceutical oil. The high cost of VCO is due to its low recovery. In order to improve the recovery, the effect of milk expelling methods (manual and mechanical) and pre- treatments (slicing, pulverizing and blanching) on coconut milk and hot process VCO recovery with respect to fresh coconut kernel weight was studied. The blanching and pulverizing yielded more milk and VCO recovery in both manual and mechanical expelling methods. The recovery of coconut milk and VCO ranged from 34.0 to 51.6 per cent and 14.2 to 22.4 per cent respectively. Among the different treatment combinations, pulverized, blanched and double screw pressed coconut kernel yielded the highest milk and VCO recovery. The per cent recovery of two important co-products namely coconut milk residue and VCO cake ranged from 38.5 to 55.6 and 6.3 to 8.8 respectively. An attempt was made to recover the oil from 8 per cent dried coconut milk residue and VCO cake in commercial oil expeller. The oil recovery from milk residue and VCO cake flour was 41.2±1.1 per cent and 25.8±1.0 per cent respectively. The dried coconut milk residue and VCO cake flour was utilized in the preparation of extrudates and sweet snacks along with the broken rice, maize grits and pearl millet grits