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Manganese peroxidase (MnP) was isolated from the culture filtrate of the wood log mushroom Stereum ostrea (S. ostrea), grown on Koroljova medium, and then purified by ammonium sulfate [70% (w/v)] fractionation, DEAE-cellulose anion exchange chromatography, and Sephadex G-100 column chromatography, with an attainment of 88.6-fold purification and the recovery of 22.8% of initial activity. According to SDS-PAGE the molecular mass of the MnP was 40 kDa. The optimal pH and temperature were found to be 4.5 and 35 degrees C, respectively. The enzyme was stable even after exposure to a pH range of 4.5 to 6.0, and at temperatures of up to 35 degrees C at a pH of 4.5 for 1h. The K(m) and V(max) values for the substrate phenol red were found to be 8 micronm and 111.14 U/mg of protein, respectively. The MnP also oxidized other substrates such as guaiacol, DMP, and veratryl alcohol. Sodium azide, EDTA, SDS, Cu(2+), and Fe(2+), at 1-5 mM, strongly inhibited enzyme activity, whereas Ca(2+) and Zn(2+) increased enzyme activity. The participation of the purified enzyme in the decolorization of dyes suggests that S. ostrea manganese peroxidase could be effectively employed in textile industries.

Major mental disorders such as schizophrenia and affective disorders are highly disabling illnesses. The cultural factors that influence the diagnosis and treatment of these disorders are of paramount clinical significance. We attempted to critically review the cultural factors in relation to the epidemiology, phenomenology, treatment, and outcome of major mental disorders from an Indian perspective, and tried to compare these with the cultural factors identified in major international studies. The clinical expression of major mental disorders was noted to vary across cultures in the review. In addition, the outcome of major mental disorders is reported to be better in developing nations than in the developed countries. Transcultural variations are also noted to exist in pharmacokinetics, pharmacodynamics, traditional healing practices, and psychotherapeutic approaches. The role of cultural factors in severe mental illnesses needs adequate attention from mental health professionals. Continued research on the cultural aspects is required to understand the interplay of all social, cultural, and biological factors. It is important to consider other cultural, traditional, and folk methods for understanding and management of mental illnesses.

Background: There is paucity of data on white matter (WM) abnormalities in juvenile obsessive-compulsive disorder (OCD). This study aimed to identify WM microstructure changes in juvenile OCD., Methods: Fifteen children and adolescents with OCD and 15 matched healthy controls underwent diffusion tensor imaging using a 3 Tesla (Achieva, Best, The Netherlands) magnetic resonance imaging scanner. Voxelwise analyses were conducted on data processed through tract-based spatial statistics (TBSS)., Results: Patients significantly differed from controls in axial as well as radial diffusivities, but not in fractional anisotropy. Patients demonstrated significantly increased axial diffusivity in corpus callosum (genu, body, and splenium), right and left superior longitudinal fasciculi, left inferior longitudinal fasciculus, right and left cingulum, bilateral anterior thalamic radiations, bilateral anterior limb of internal capsule, left posterior limb of the internal capsule, and middle cerebellar peduncle. In addition, significantly increased radial diffusivity was seen in patients in genu of the corpus, right and left superior longitudinal fasciculi, left inferior longitudinal fasciculus, right and left uncinate fasciculi, bilateral anterior thalamic radiation, bilateral inferior fronto-occipital fasciculus, left posterior limb of internal capsule, right superior cerebellar peduncle, middle cerebellar peduncle, and right inferior cerebellar peduncle., Conclusions: Our findings suggest involvement of multiple WM tracts in juvenile OCD. In addition to the widely proposed hypothesis of orbitofrontal-striato-thalamo-cortical circuitry deficits in the development of OCD, our findings suggest involvement of additional brain regions, possibly parietal cortex, lateral prefrontal cortex, and limbic system. The widespread differences in WM among cases and controls also points to the possibility of underlying myelination changes., (© 2012 Wiley Periodicals, Inc.)

Background: The identification of distinct subtypes based on comorbidity offers potential utility in understanding variations in the clinical expression of obsessive-compulsive disorder (OCD). Hence, we examined the hypothesis whether patients with OCD with major depressive disorder (MDD) or anxiety disorder comorbidity would differ from those without in terms of phenomenology., Methods: A total of 545 consecutive patients who consulted a specialty OCD clinic during the period 2004 to 2009 at a psychiatric hospital in India formed the sample. They were evaluated with the Yale-Brown Obsessive-Compulsive Scale (YBOCS), the Mini International Neuropsychiatric Interview, and the Clinical Global Impression scale., Results: Among 545 patients, 165 (30%) had current MDD, and 114 (21%) had current anxiety disorder comorbidity. Patients with OCD with MDD were mostly women who had a greater severity of OCD symptoms, more of obsessions (especially religious), greater occurrence of miscellaneous compulsions (need to confess or need to touch), higher suicidal risk, and past suicidal attempts. Patients with OCD with anxiety disorder had an earlier onset of illness that was associated with prior life events, less of compulsions, more of aggressive and hoarding obsessions, pathologic doubts, checking, and cognitive compulsions., Conclusions: Obsessive-compulsive disorder, when comorbid with MDD, is more severe and is associated with higher suicidal risk. On the other hand, anxiety disorder comorbidity seems to influence not so much the morbidity but the phenotypic expression of OCD., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: This study aims to understand the sociodemographic and clinical profile of inhalant abusers seeking treatment from a tertiary care psychiatric hospital in South India., Materials and Methods: The clinical charts of patients who utilized the psychiatric services of a tertiary care center in India for over 10 years were examined for the study., Results: The sample had an urban predominance, was mostly unemployed, and was all male. Most of them had an adolescent age of onset of inhalant use (mean - 16.23 years). All patients reported the use of volatile solvents as inhalants. One other substance dependence was identified in more than half of the sample. The psychiatric comorbidity included psychosis and depression. A comparison was made between patients who presented with inhalant dependence only (I) and inhalant-dependent individuals who also used other psychoactive substances apart from nicotine (IP). The inhalant-only group (I) had an earlier mean age at onset of substance use as compared to the IP group. All patients in the I group reported withdrawal symptoms compared to 77% of patients in the (IP) group (P=0.048). The IP group reported a significantly higher occurrence of aggression (54.5 vs. 19%, P=0.02), externalizing symptoms (77.3 vs. 42.9%, P=0.03), and attention-deficit hyperactivity disorder (ADHD) (50 vs. 14.3%, P=0.02)., Conclusion: Inhalant dependence is a serious health problem in adolescent subjects and is associated with high comorbidity of other substance dependence, psychiatric disorder, and externalizing spectrum disorder. There is a need for community-based prospective studies in this area from India.

Opioid dependence is a chronic relapsing condition which requires comprehensive care; pharmacological agents form the mainstay of its long term treatment. The two most popular approaches are the harm reduction method using agonists and the complete abstinence method using antagonists. Currently, particularly from the harm minimization perspective and the low feasibility of an abstinence based approach, there is an increasing trend toward agonist treatment. The use of buprenorphine has gained popularity in view of its safety profile and the availability of the buprenorphine-naloxone combination has made it popular as a take-home treatment. This review outlines the pharmacological advances and controversies in this area., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objective: To study relationship between insight and clinical characteristics in subjects with obsessive-compulsive disorder (OCD)., Method: Sample included 545 consecutive patients with a primary diagnosis of DSM-IV OCD who consulted a specialty OCD Clinic at a tertiary psychiatric hospital in India between January 2004 and December 2009. They had been evaluated with the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) symptom checklist, severity rating scale and the item 11 for insight, the Mini International Neuropsychiatric Interview (MINI) and the Clinical Global Impression scale (CGI). Regression analyses were performed to identify predictors of insight., Results: The sample had 498 (91%) subjects with good insight (score≤2) and 47 (9%) subjects with poor insight (score>2) as per the Y-BOCS item11. Poor insight group had a significantly higher score on the Y-BOCS compulsions (p<0.001) and total score (p=0.001), the CGI-Severity (p=0.001) and a higher rate of contamination fears (p<0.001) and washing compulsions (p<0.001). Good insight group had a significantly higher frequency of aggressive obsessions (p<0.001). In linear regression, contamination dimension (p=0.007) and Y-BOCS total score (p<0.001) predicted poorer insight and presence of forbidden thoughts (p=0.006) predicted better insight., Limitations: Study sample is from a specialty OCD clinic of a major psychiatric hospital in India and therefore, generalizability to other clinical settings may be limited., Conclusion: Poor insight is associated with severe form of OCD, and is associated with contamination dimension. That degree of insight has specific correlation with certain symptom dimensions adds to the growing knowledge on the dimensional aspect of OCD. Insight has to be systematically assessed in all OCD subjects particularly in those with contamination fears. Failure to systematically assess insight may have treatment implications., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objective: The study aimed at comparing the psychiatric morbidity in geriatric versus nongeriatric (NG) adults during the initial 3 months following the December 2004 tsunami involving the Andaman and Nicobar Islands, India., Methods: This observational study was undertaken during the relief operation of tsunami. There were 12,784 survivors sheltered across 74 relief camps with 4,684 displaced survivors in Port Blair, and 8,100 nondisplaced survivors in Car Nicobar Island. All persons who accessed mental health assistance within the camps constituted the study sample. Diagnoses were made by qualified psychiatrists using the International Classification of Diseases, Tenth Revision. There were 438 adult patients, of which 75 (17%) were geriatric (60 years or older) and 363 (83%) were NG (aged 19-59 years)., Results: The geriatric sample had greater levels of adjustment disorder than NG group. The two groups differed in terms of displacement as the elderly preferred to stay in their own locality. A comparison between displaced geriatric and NG groups showed that major depression was less common in the geriatric sample. However, in the nondisplaced group, geriatric subgroup showed a higher incidence of posttraumatic stress disorder. Within the geriatric sample, there were higher levels of adjustment disorder in the nondisplaced group whereas the displaced group suffered more depressive episodes and unspecified anxiety disorders., Conclusion: Greater levels of adjustment disorder in geriatric group may indicate grief reaction and survivor guilt, especially in nondisplaced group. In addition, lower occurrences of depressive episodes in nondisplaced geriatric sample may indicate that the elderly need to be rehabilitated in their own habitats after major disasters.

Context: Studies on acute psychosis in patients from India report good outcome. A small proportion of these patients may suffer relapses or other develop major psychiatric disorders later., Aim: The aim of this study was to examine the diagnostic stability of acute psychosis in patients from India., Materials and Methods: The records of patients who presented with the first episode of acute and transient psychotic disorder (n=57) over 1 year (2004) were analyzed, and the follow-up data at the end of 1 and 2 years were recorded., Results: The mean age of the sample was 30.72 years. The mean duration of illness episode was 18.15±17.10 days. The follow-up data were available for 77.2% (n=44) and 75.4% (n=43) of the sample at the end of first and second years. Relapse was recorded in 47.4 and 54.4% at the end of first and second years, respectively., Conclusion: The diagnosis changed into other disorders such as bipolar disorder, schizophrenia, and unspecified psychosis, while a majority retained the initial diagnosis of acute psychosis. The findings suggest that acute psychosis is a relatively stable condition. A small percentage of these patients may go on to develop schizophrenia or bipolar disorder.

Background: Obsessive-compulsive disorder (OCD) is associated with impairments in multiple neuropsychological domains but the findings are rather inconsistent across studies. One potential reason for poor replication is the confounding influence of medications. There is limited research on neuropsychological performance in medication-naïve, never treated OCD patients., Methods: In this study, we assessed 31 medication-naïve, never-treated, DSM-IV OCD patients free of comorbid major depression and 31 healthy controls individually matched for age, gender and years of education, with tests of attention, executive function, memory reasoning and visuo-spatial function., Results: Medication-naïve OCD patients did not significantly differ from healthy controls on most neuropsychological tests. Patients performed somewhat poorly only on the highest goal hierarchy of the Tower of London (TOL) test (p=0.001, effect size=0.68)., Conclusions: It is intriguing to find that symptomatic, drug-naïve OCD patients did not significantly differ from healthy controls on most neuropsychological tests. Our finding of medium effect size on TOL highest goal hierarchy test suggests that brain regions outside the affective orbitofrontal loop may also be perhaps involved in OCD. This finding however needs replication because of modest effect size. Future studies should focus on studying medication-naïve, co-morbidity-free patients and relatives using symptom dimensions for consistent and robust findings., (Copyright © 2011 Elsevier Inc. All rights reserved.)

We present a simple template-free method for the synthesis of interconnected hierarchical porous palladium nanostructures by controlling the aggregation of nanoparticles in organic media. The interaction between the nanoparticles is tuned by varying the dielectric constant of the medium consistent with DLVO calculations. The reaction products range from discrete nanoparticles to compact porous clusters with large specific surface areas. The nanoclusters exhibit hierarchical porosity and are found to exhibit excellent activity towards the reduction of 4-nitrophenol into 4-aminophenol and hydrogen oxidation. The method opens up possibilities for synthesizing porous clusters of other functional inorganics in organic media.

Background: Bifrontal (BF) placement of electrodes in electroconvulsive therapy (ECT) has emerged as an alternative option to the conventional bitemporal (BT) and right unilateral electrode placement in view of fewer cognitive adverse effects. However, the results have been contradictory in terms of clinical efficacy., Materials and Methods: We studied the records of all patients referred for ECT between the months of August 2008 and July 2010 (n=1575). One hundred and five of these patients had received BF-ECT. These records were compared with the records of 105 patients who received BT-ECT. For each patient who received BF-ECT, the very next person posted for BT-ECT was taken as the control. All patients received bilateral ECTs at 1.5-times the threshold stimulus dose. The number of ECTs administered, duration of hospital stay after ECT initiation, seizure threshold and failure to achieve adequate seizures were compared. Two raters who achieved good inter-rater reliability assessed the initial severity using the clinical global impression scale and clinical improvement using a Likert scale., Results: The speed of response, as assessed by the number of ECTs received and the duration of hospital stay after ECT initiation was similar in the two groups. In addition, both groups were comparable in terms of clinical improvement scores on the Likert scale. BF-ECT patients also had a significantly higher seizure threshold, which remained significant in spite of controlling for age. This study is chart based, with its inherent limitations. Standard outcome measures were not used. Cognitive adverse effects were not studied., Conclusions: BF-ECT performed similar to BT-ECT with regard to therapeutic efficacy. Given the consistent results of the former, with fewer cognitive side-effects, the findings of the present study support BF-ECT as the first line for electrode application.

Background: Familial and sporadic subtypes of obsessive-compulsive disorder (OCD) have been proposed, but have not been well studied. The aim of the study was to compare the clinical characteristics, comorbidity and treatment response of familial OCD with sporadic OCD., Sampling and Methods: We reviewed the clinical records of 84 familial OCD patients and 80 randomly selected sporadic OCD patients from a specialty OCD clinic in India. All the subjects had been evaluated using the specially devised topical OCD evaluation proforma, the Yale-Brown Obsessive Compulsive Scale and the Clinical Global Impression scale. A diagnosis of OCD was made according to the DSM-IV criteria., Results: Familial OCD was associated with earlier age at onset, a greater duration of untreated illness and more compulsions, particularly ordering and cognitive types. It was also associated with greater comorbidity, especially depression and other anxiety disorders, and treatment non-response. The sporadic group had more sexual obsessions and predominant obsession subtypes of OCD. In regression analysis, ordering compulsions, cognitive compulsions, absence of sexual obsessions, lifetime comorbidity of major depression and anxiety disorders and a greater duration of untreated illness predicted familial OCD., Conclusions: Our findings support the observation that familial OCD could be phenotypically different from sporadic forms of OCD and therefore a putative subtype of OCD., (Copyright © 2010 S. Karger AG, Basel.)

Production of lignolytic enzymes by the mushroom fungus Stereum ostrea in liquid medium under conditions of vegetative growth was examined for 10 days in comparison to the reference culture Phanerochaete chrysosporium. Though growth and secretion of extracellular protein by S. ostrea were comparable to those of P. chrysosporium, yields of laccase enzyme by S. ostrea were higher than laccase titres of P. chrysosporium by more than 2 folds on the peak production time interval (IVth day of incubation). S. ostrea yielded titres of 25 units of laccase/ml as against 8.9 units of laccase/ml on the IVth day of incubation. Stereum ostrea also exhibited activities of other lignolytic enzymes, lignin peroxidase (LiP) and manganese peroxidase (MnP), higher than the reference culture. Growth of S. ostrea on the medium in the presence of Remazol orange 16 resulted in the decolourisation of dye, confirming the presence of lignolytic enzymes. S. ostrea appears to be a promising culture with complete lignolytic system.

The generation of brine solutions from dense membrane (reverse osmosis, RO or nanofiltration, NF) water reclamation systems has been increasing worldwide, and the lack of cost effective disposal options is becoming a critical water resources management issue. In Singapore, NEWater is the product of a multiple barrier water reclamation process from secondary treated domestic effluent using MF/UF-RO and UV technologies. The RO brine (concentrates) accounts for more than 20% of the total flow treated. To increase the water recovery and treat the RO brine, a CDI based process with BAC as pretreatment was tested. The results show that ion concentrations in CDI product were low except SiO2 when compared with RO feed water. CDI product was passed through a RO and the RO permeate was of better quality including low SiO2 as compared to NEWater quality. It could be beneficial to use a dedicated RO operated at optimum conditions with better performance to recover the water. BAC was able to achieve 15-27% TOC removal of RO brine. CDI had been tested at a water recovery ranging from 71.6 to 92.3%. CDI based RO brine treatment could improve overall water recovery of NEWater production over 90%. It was found that calcium phosphate scaling and organic fouling was the major cause of CDI pressure increase. Ozone disinfection and sodium bisulfite dosing were able to reduce CDI fouling rate. For sustainable operation of CDI organic fouling control and effective organic fouling cleaning should be further studied.

Dendritic Pd with corrugated surfaces, obtained by a novel AC technique, exhibits an exceptionally high catalytic activity for the oxidation of formic acid because of the presence of a high density of surface steps. The formation of twinned dendrites leads to a predominance of exposed 111 facets with a high density of surface steps as evident from high resolution electron microscopy investigations. These surface sites provide active sites for the adsorption of the formic acid molecules, thereby enhancing the reaction rate. Control experiments by varying the time of deposition reveal the formation of partially grown dendrites at shorter times indicating that the dendrites were formed by growth rather than particle attachment. Our deposition method opens up interesting possibilities to produce anisotropic nanostructures with corrugated surfaces by exploiting the perturbations involved in the growth process.

A local isolate of Aspergillus niger was cultivated under optimal growth conditions on wheat bran in solid state fermentation. β-endoglucanase from fermented bran was separately extracted with different solvents to test recovery of enzyme. Among solvents tested, distilled water served the best leachate. Conditions were further optimized with this leachate. Two washes of fermented bran with the leachate for 30 min each under shaking conditions in a ratio of 1 g of wheat bran: 4 ml of distilled water together yielded maximum recovery of 16.7 U/g of wheat bran.

We report a general method for the synthesis of hollow structures of a variety of functional inorganics by partial sintering of mesoporous nanocrystal aggregates. The formation of a thin shell initiates the transport of mass from the interior leading to growth of the shell. The principles are general and the hollow structures thus produced are attractive for many applications including catalysis, drug delivery and biosensing.

p-Aminobenzoate ion intercalated alpha-hydroxides of nickel/cobalt were synthesized by precipitation using ammonia (pH= approximately 12). Aqueous colloidal suspension of alpha-hydroxide of nickel/cobalt was obtained on washing the precipitate as the pH was reduced to approximately 7. The development of partial positive charge on the amine end of the intercalated anion causes repulsion between the layers leading to exfoliation and colloidal suspension of monolayers in water. While the layers could be restacked from the colloidal suspension in the presence of other anions in the case of alpha-cobalt hydroxide, the exfoliation could not be reversed easily in the case of the nickel analog., (Copyright 2010 Elsevier Inc. All rights reserved.)

Creating nanoscale heterostructures with molecular-scale (<2 nm) metal wires is critical for many applications and remains a challenge. Here, we report the first time synthesis of nanoscale heterostructures with single-crystal molecular-scale Au nanowires attached to different nanostructure substrates. Our method involves the formation of Au nanoparticle seeds by the reduction of rocksalt AuCl nanocubes heterogeneously nucleated on the substrates and subsequent nanowire growth by oriented attachment of Au nanoparticles from the solution phase. Nanoscale heterostructures fabricated by such site-specific nucleation and growth are attractive for many applications including nanoelectronic device wiring, catalysis, and sensing.

Reverse osmosis (RO) reject recovery from the water reclamation process was demonstrated feasible using an integrated pretreatment scheme followed by the Capacitive Deionization (CDI) process. The RO reject had an average total dissolved solids (TDS) of 1276+/-166 mg/L. Water recovery of 85% with water quality comparable with the RO feed was achieved. Pretreatments using biological activated carbon (BAC) and BAC-ultrafiltration (UF) attained total organic carbon (TOC) removal efficiencies of 23.5+/-6.0% and 39.9+/-9.0%, respectively. Organics removal of RO reject was attributed to simultaneous adsorption and biodegradation in the BAC pretreatment, while further biodegradation in the submerged UF membrane tank provided additional organics removal. Membrane and CDI fouling was reduced by pH adjustment of the pretreated RO reject to approximately 6.5, which prolonged the CDI operation time by at least two times. The CDI process was able to achieve more than 88 and 87% TDS and ion removals, respectively, while PO(4)(3-) and TOC removals were at 52-81% and 50-63%, respectively.

Ozonation was used in this study to improve biodegradability of RO brine from water reclamation facilities. An ozone dosage ranging from 3 to 10 mg O(3)/L and contact times of 10 and 20 min in batch studies were found to increase the biodegradability (BOD(5)/TOC ratio) of the RO brine by 1.8-3.5 times. At the same time, total organic carbon (TOC) removal was in the range of 5.3-24.5%. The lab-scale ozone-biological activated carbon (BAC) at an ozone dosage of 6.0mg O(3)/L with 20-min contact time was able to achieve 3 times higher TOC removal compared to using BAC alone. Further processing with Capacitive Deionization (CDI) process was able to generate a product water with better water quality than the RO feed water, i.e., with more than 80% ions removal and a lower TOC concentration. The ozone-BAC pretreatment has the potential of reducing fouling in the CDI process.

Background: Impairments in executive functions and non-verbal memory are considered potential endophenotype markers of obsessive-compulsive disorder (OCD). For the neuropsychological deficits to be considered endophenotypes, they should be demonstrable in unaffected family members., Aim: To compare the neuropsychological performance in unaffected siblings of probands with familial OCD with that of individually matched healthy controls., Methods: Twenty-five unaffected siblings of OCD probands with familial OCD, and 25 individually matched healthy controls were assessed with tests of attention, executive function, memory and intelligence., Results: Unaffected siblings showed significant deficits in tests of decision making and behavioural reversal i.e., the Iowa Gambling Task (IGT) and the Delayed Alternation Test (DAT) respectively, but performed adequately in other tests., Conclusions: Our study suggests that the deficits in decision making and behavioural reversal could be potential endophenotypes in OCD. These deficits are consistent with the proposed neurobiological model of OCD involving the orbitofrontal cortex. Future studies could couple cognitive and imaging strategies to identify neurocognitive endophenotypes in homogenous samples of OCD.

Nanoporous structures with high active surface areas are critical for a variety of applications. Here, we present a general templateless strategy to produce such porous structures by controlled aggregation of nanostructured subunits and apply the principles for synthesizing nanoporous Pt for electrocatalytic oxidation of methanol. The nature of the aggregate produced is controlled by tuning the electrostatic interaction between surfactant-free nanoparticles in the solution phase. When the repulsive force between the particles is very large, the particles are stabilized in the solution while instantaneous aggregation leading to fractal-like structures results when the repulsive force is very low. Controlling the repulsive interaction to an optimum, intermediate value results in the formation of compact structures with very large surface areas. In the case of Pt, nanoporous clusters with an extremely high specific surface area (39 m2/g) and high activity for methanol oxidation have been produced. Preliminary investigations indicate that the method is general and can be easily extended to produce nanoporous structures of many inorganic materials.

Understanding shape control during wet chemical synthesis is important for rational synthesis of nanostructures. Here, we show that two-dimensional metal structures can be obtained from metal salts by reducing the driving force of the reduction reaction that directly translates to the growth of the metal taking place by the two-dimensional nucleation (layer-by-layer growth) mechanism. Experimental evidence is provided for Au, Ag, Pt and Pd systems by choosing appropriate reaction conditions without using any external surfactant. The results are analyzed in terms of the calculations of driving force under different conditions. The results show that surfactants may not be important for producing shape control for the case of 2-D structures while they are required to obtain size control. It is shown that the regime of low driving force is also one where the kinetics of the process is slow and thus a new interpretation of the kinetic control hypothesis is provided.

A general methodology for predicting the conditions for the formation of plate-shaped structures by precipitation has been developed. The method has been applied for understanding the morphology of hydroxyapatite formed under different synthetic conditions. Morphology diagram has been developed in the form of pH-T diagrams to predict regions where plate-shaped hydroxyapatite is expected to form. The validity of the morphology diagram has been tested by critical experiments carried out at different conditions coupled with detailed microstructural analysis. Different morphologies ranging from single crystalline sheets, rods to equiaxed particles of hydroxyapatite are achieved by tuning the driving force of the precipitation reactions by varying the parameters such as pH and temperature in the absence of capping/surfactant agents. The synthesis and analysis presented here have important implications for understanding the plate-shaped morphology of apatite crystals that exist in the bone.

Mechanical properties of flux-grown tricalcium phosphate (TCP) single crystals ranging in size from 50 to 75microm have been characterized by performing micro- and nanoindentation on their facets. Notwithstanding the inherent brittleness and anisotropy, these single crystals exhibit nanoscale plasticity in the form of pile-up around the edges of indents. A similar plastic response was observed in hydroxyapatite (HA) single crystals during nanoindentation in an earlier study. The hardness and elastic modulus obtained during nanoindentation are discussed in comparison with the polycrystalline forms of both TCP and HA found in the literature. The indentation fracture toughness values of TCP single crystals were found to be higher than those of HA single crystals. The higher values are attributed not only to the difference in crystal structure and corresponding differences in surface energy, but also to extensive crack bridging by ligament formation across crack faces during crack propagation.

The ability to predict the morphology of crystals formed by chemical reactions is of fundamental importance for the shape-controlled synthesis of nanostructures. Based on the atomistic mechanism for crystal growth under different driving forces, we have developed morphology diagrams to predict regimes for the growth of two-dimensional crystals. By using controlled reactions for crystal growth in the absence of surfactants/capping agents, we demonstrate the validity of this approach for the formation of 2D structures of Au, Ag, Pt and Pd.

The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the enzymes occurred within 3 days of incubation. Among solid supports used in the study, wheat bran was the best solid matrix followed by groundnut fodder in production of cellulolytic enzymes in solid state fermentation. Groundnut fodder supported significant production of FPase (2.09 FPU/g), CMCase (1.36 U/g) and -glucosidase activity (0.0117 U/g) in solid state fermentation. Considerable secretion of protein (5.10 mg/g) on groundnut fodder at peak time interval 1st day of incubation was recorded.

Interaction effects of the insecticides monocrotophos and quinalphos (organophosphates), and cypermethrin (pyrethroid), on microbial activities in two agricultural soils-black vertisol soil and red alfinsol soil were tested for 30 days under laboratory conditions. Individual application of the three insecticides at 5, 10 and 25microg g(-1) to the soil distinctly enhanced the activities of cellulase and amylase. Insecticide combinations involving monocrotophos or quinalphos with cypermethrin yielded synergistic, antagonistic and additive interaction effects on both enzymes in the soils. At lower levels, 5 and 10microg g(-1), the insecticides in combination interacted additively or synergistically toward both enzymes. But, both combinations at the highest level of 25microg g(-1) exhibited an antagonistic interaction, with a reduction in enzyme activities to a level lower than that of the control. Interaction effects of insecticides in combinations on two enzyme activities in both soils were related to populations of cellulolytic and amylolytic organisms in soils under the impact of combination of insecticides. These interaction responses were persistent even for 30 days.

Singapore has been using dual membrane technology (MF/UF RO) to produce high-grade water (NEWater) from secondary treated sewage. Membrane bioreactor (MBR) has very high potential and will lead to the further improvement of the productivity and quality of high-grade water. This study was focused on the technical feasibility of MBR system for water reclamation in Singapore, making a comparison between various membrane systems available and to get operational experience in terms of membrane cleaning and other issues. Three MBR plants were built at Bedok Water Reclamation Plant with a design flow of 300 m3/day each. They were commissioned in March 2003. Three different types of submerged membranes were tested. They are Membrane A, plate sheet membrane with pore size of 0.4 microm; Membrane B, hollow fibre membrane with pore size of 0.4 microm; and Membrane C, hollow fibre membrane with pore size of 0.035 microm. The permeate quality of all the three MBR Systems were found equivalent to or better than that of the conventional tertiary treatment by ultrafiltration. MBR permeate TOC was about 2 mg/l lower than UF permeate TOC. GC-MS, GC-ECD and HPLC scan results show that trace organic contaminants in MBR permeate and UF permeate were in the same range. MBR power consumption can be less than 1 kwh/m3. Gel layer or dynamic membrane generated on the submerged membrane surface played an important role for the lower MBR permeate TOC than the supernatant TOC in the membrane tank. Intensive chemical cleaning can temporarily remove this layer. During normal operation conditions, the formation of dynamic membrane may need one day to obtain the steady low TOC levels in MBR permeate.

An aerobiological survey to study the incidence and concentration of the pollen of Parthenium hysterophorus was conducted in Bangalore, India for a period of one year. This study indicated that Parthenium pollen was present in the atmosphere in significant amounts eigher as single pollen grains or in the form of clumps during the months of June to August.