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Background: Motivational deficits are a central feature of the negative syndrome in schizophrenia. They have consistently been associated with reduced willingness to expend physical effort in return for monetary rewards on effort based decision making (EBDM) paradigms. Nevertheless, the mechanisms underlying such altered performance are not well characterised, and it remains unclear if they are driven purely by negative symptoms, or also in part by cognitive impairment, antipsychotic treatment or even positive symptoms. Here we investigated the impact of all these factors using a paradigm that has not previously been used to measure EBDM in schizophrenia. Methods: Forty treatment resistant schizophrenia (TRS) patients on clozapine and matched controls (N= 80) completed a well validated EBDM task which offers monetary rewards in return for physical effort. Choice and reaction time data was analysed using logistic regressions, as well as Bayesian hierarchical drift diffusion modelling (HDDM). Behavioural parameters were compared between groups and their association with negative symptoms, cognitive function and serum clozapine levels were assessed. Results: Overall, TRS patients accepted significantly less offers than controls during effort-based decision making, suggesting they were less motivated. They demonstrated reduced sensitivity to increasing rewards, but surprisingly were also less averse to increasing effort. Despite a positive correlation between negative symptoms and cognitive function in TRS, reward sensitivity was associated only with cognitive performance. In contrast, reduced effort aversion correlated with negative symptom severity. Clozapine levels and positive symptoms were not associated with either behavioural parameter. Conclusion: Motivational deficits in TRS are characterised by both diminished reward sensitivity and reduced effort aversion during EBDM. Cognitive dysfunction and negative symptom severity account for distinct aspects of these behavioural changes, despite positive associations between themselves. Overall, these findings demonstrate that negative symptoms and cognitive impairment have significant independent contributions to EBDM in TRS, thereby opening the possibility of individualised treatment targeting these mechanisms to improve motivation.

Today's and tomorrow's secret data exchange relies heavily on cryptography. Cryptographic applications offer a secure communication channel for safely transferring data. It provides individuals, groups, and organizations with greater privacy and access to communication and other information, as well as the opportunity to restore personal privacy. Nowadays, online users desire to create an account in order to get access to certain websites, such as online tutorials, online purchases, online resource access, hosting services, social networking sites, and so on. However, unless the service provider or authority person ensures that the registration and login processes are genuine, there is a potential that the account might be hacked by a third party using the ordinary user access method. With the growing usage of cloud emails and frequent reports of large-scale leakage occurrences, a security attribute known as forward secrecy becomes desired and necessary for both users and cloud service providers to improve the security of cloud email systems.

Agriculture improvement is a global economic issue and ongoing challenge in this covid-19 pandemic that is highly dependent on effectiveness. The recognition of the diseases in plant leaf performs a major role in the agriculture industry and city-side greenhouse farms approximate analysis of the leaf disease this article intends to integrate image processing techniques with the “convolutional neural network”, which is one of the deep learning approaches, to classify and detect plant leaf disease and publicly available plant the late data to help treat the leaf as early as possible, which controls the economic loss. This paper has a set that was used which consists of 10 classes of disease and three classes of a plant leaf, this research offers an effective method for detecting different diseases in plant leaf variations. The model was created to detect and recognize healthy plant kinds, such as tomato and potato, and pepper these three leaves will perform under the algorithm called a convolutional neural network. By modifying the parameters and changing the pulling combination, models that have been used to train and test these types of leaf sample images can be created. leaf disease recognition was based on these 10 different types of classes in three different species tomato, potato, and pepper the classification of sample images has reached diseases identification accuracy.

Nowadays, non-contact type position sensors are gaining confidence due to their wear free sensing in motor control application as positional feedback. This paper proposes a simple design methodology of Resonant Spiral Inductor Position Sensor by a computer aided design in sliding door application. The positional accuracy of sensor depends on the dimensions of spiral inductors, coupling between excitation coil and resonator. An accurate prediction of inductance of sine and cosine shape spiral inductors and sensor characteristics is very critical in sensor design. This method uses analytical approach to predict the inductances of spiral inductors of rectangular, sine and cosine shapes. Further, it uses transfer function model derived from an equivalent circuit of both sine and cosine output spiral coils from the basics of magnetic coupling between excitation and resonator coils. In this model, the inductances of both sine and cosine output coils and the output voltages are predicted. This has been implemented in MATLAB environment through Graphical User Interface (GUI) along with its signal conditioning algorithm to predict the linear position of the moving resonator which is attached with the target whose position is to be sensed. The accuracy of the sensor is also predicted through an error calculation by comparing the measurement results with actual position in ideal condition.This methodology helps to do a quick design in days with good accuracy and also provides significant reduction in design cycle time when compared to Finite Element and Measurement method which takes months to arrive at an optimum design.

The changes in the socio-political and economic climate in Poland since 1989 have had an adverse effect on its research and development programs. Cooperation among industry, the academe and the government for technological advancement before 1989 relied heavily on government subsidy and control. A joint venture law passed in 1990 allowed the privatization and commercialization of research and its applications. Some problems encountered by industry include budgetary constraints, mismanagement and the poor quality of research projects.

Background: Linagliptin (LNG) is an oral hypoglycemic agent that acts by inhibiting the enzyme dipeptidyl peptidase - 4 (DPP-4) and reduces blood sugar levels in type-II diabetic patients. To date, the literature presents few analytical methods for the determination of LNG. However, no reversed phase-high performance liquid chromatography (RP-HPLC) method has been reported for the determination of LNG in nanotransfersomes and in vitroskin permeation samples. Objective: The present study involves the development and validation of RP-HPLC method to quantify LNG in both nanotransfersomes and in vitroskin permeation and deposition samples. Methods: The chromatographic analysis was performed on Luna C18 (2) column (250 x 4.6 mm, 5μm particle size) with a mobile phase consisting of a mixture of methanol: 0.2% orthophosphoric acid (50:50, v/v) at a flow rate of 1.0 mL/min, detection wavelength of 227 nm, and column temperature of 40 °C. Results: The method was found to be specific, linear (r2≥ 0.999; 2-12 μg/mL), precise at both intra and inter-day levels (percentage relative standard deviation; % RSD < 2.00), accurate (percentage recovery 100.21-103.83%), and robust. The detection and quantification limits were 0.27 and 0.82 μg/mL, respectively. The mean % entrapment efficiency and the cumulative amount of LNG permeated across the rat skin from different transfersomal formulations ranged between 40.78 ± 2.54 % to 52.26 ± 2.15 % and 79.54 ± 16.67 to 200.74 ± 35.13 μg/cm2respectively. Conclusion: The method was successfully applied to determine the entrapment efficiency, in vitroskin permeation and deposition behavior of LNG-nanotransfersomes.

Aim: The cancer stem cells (CSCs) are known to be responsible for drug resistance and cancer relapse in the treatment of cancer. Identification and isolation of CSCs and study of their properties will play a crucial role in developing an effective drug against these targets. The aim of the study was to isolate CSCs from primary cancer by the tumorspheres enrichment method, to confirm by indirect immunofluorescence and gene expression of stem cell markers by using real-time polymerase chain reaction (RT-PCR) technique.Materials and Methods: In this in vitro study, we enriched oral CSCs through tumorsphere formation assay from seven primary cultures of OSCC patients with defined serum media. The expression and localization of the cell surface markers of CD133 and CD44 were tested by indirect immunofluorescence. Gene expression of stem cell markers such as CD44, CD133, Oct4, Sox2, and Nanog were quantified by RT-PCR technique. One-way analysis of variance was applied to analyze gene expression.Results: Tumorsphere formation has been used to isolate the CSCs from the OSCC tissue culture. Both CD133 and CD44 antibody confirmed the presence of CSCs through indirect immunofluorescence. In comparison to parental cell lines, the expression levels of CD133, CD44, Oct4, Sox2, and Nanog stem cell were significantly higher in CSC-enriched subpopulations.Conclusions: The cost-effective spheroid enrichment and the indirect immunofluorescence methods are useful for the isolation of CSCs from the primary tumor.

Byline: Tom Bramorski, Manohar S. Madan The framework for industry-university-government cooperation in research and development (R&D) in Poland has undergone significant changes in recent years as a result of political and economic liberalization. The role of large government-controlled enterprises and government agencies in supporting R&D has diminished. The dynamically growing small business sector has not been able to fill the vacuum left by these entities in sponsoring R&D. Significant progress in disarmament between East and West and the collapse of the Warsaw Pact have decreased the demand for defence-related R&D. The liberalization of trade policies and the abolition of most Coordinating Committee on Multilateral Export Controls (COCOM) restrictions on technology transfer to Poland have reduced the need to undertake domestic R&D efforts in non-military areas. The unstable business environment and prevailing traditional management practices make difficult the creation of effective agreements with foreign partners in the field of technology management. In this paper we examine the changes that have taken place in Poland in the system of technology management and make recommendations for the future.

Background and Aims: Porphyromonas gingivalis(P. gingivalis) is considered as an important pathogen responsible for periodontal disease which is characterized by inflammation of gingiva and destruction of periodontal ligament and alveolar bone leading to loss of tooth. Along with clinical investigations, suitable microbiological analysis needs to be performed which could provide more insight into the disease severity. We aim to quantify P. gingivalisby real-time PCR (RT-PCR) and analyze its association with demographic data including clinical parameters.Materials and Methods: The study consisted of chronic periodontitis patients (CP group) and healthy subjects (H group) with 120 samples in each group. RT-PCR was carried out by the SYBR Green assay to target 16S ribosomal ribonucleic acid species-specific region of P. gingivalis. Standard strain of P. gingivalisATCC 33277 was used as a control.Results: In the CP group, 79.16% samples were found positive for P. gingivalis, whereas 29.17% samples were positive in the H group. A significant difference was found when the prevalence was compared within males and females (P< .001 for both). In the older age groups, we found a higher rate of detection of P. gingivalis. As analyzed by Spearman’s correlation test, the number of cells of P. gingivaliswas significantly associated with probing depth (P= .02) and clinical attachment level (P = .01) in the CP group. The mean cell number of P. gingivaliswas found to be increasing with increasing levels of probing depth and clinical attachment level (P< .001 and P= .01, respectively).Conclusion: The present study reaffirms that the P. gingivalismicrobe is significantly associated with the chronic periodontitis and that its level varies with the severity of the disease. Colonization of the bacterium is significantly associated with severe forms of the disease.

Damage control surgery may save the lives of patients with acute traumatic injuries who are in unstable condition, and CT before and after surgery can help with diagnosis and ultimate injury repair.

Aims and Objectives: The oral microbial flora is highly complex and diverse with obligate anaerobic bacteria as the predominant component. Most of these are not yet cultivated/difficult to cultivate due to technical limitations. In this study, we aim to detect two novel oral bacterial species Dialister invisusand Olsenella uliby simplified and economical procedure of polymerase chain reaction (PCR) and study their association with primary and persistent endodontic infections.Material and Methods: The study involved 60 patients that included 30 patients of primary endodontic infections and 30 with persistent endodontic infections. The sample collection from the root canal was performed by universally accepted protocol by using sterile paper points. The deoxyribonucleic acid (DNA) extraction was done, followed by PCR with species specific primers. We made several changes to the protocol mentioned by original authors. We adopted a one-step protocol for amplification of bacterial DNA, omitting the 16SrDNA amplification step with universal primers.Results: It was seen that 7 (23.3 %) samples in primary endodontic infection group and 24 (80 %) samples in persistent endodontic infection group were positive for D. invisus. On the other hand, 11 (36.6 %) patients of primary endodontic infection showed positivity for O. uliin comparison to 9 (30 %) of persistent endodontic infection.Conclusion: The results from the present study showed efficient amplification of both O. uliand D. invisusin a single-step PCR. Hence, we conclude that the modified protocol used here with taq polymerase enzyme offers a faster and cheaper alternative to nested PCR without compromising the quality of amplification process.

AbstractThis research-in-progress paper describes a study of data mining using historical manufacturing test data at an electronic circuit board assembly firm. The purpose of this data mining is to determine, if in a multi-step manufacturing process at small and medium manufacturing firm downstream production problems can be identified and prevented by evaluating up stream data. While quantitative analysis and data mining have been used in manufacturing, the scope of their application is generally limited to a specific step or process that is a first order analysis of the data.

The syndrome of apathy has generated increasing interest in recent years as systematic evaluations have revealed its high prevalence and strong negative impact on quality of life across a wide range of neurological and psychiatric conditions. However, although several theoretical models have been proposed to account for various aspects of the condition, understanding of this syndrome is still incomplete. One influential model has proposed that apathy might be described as a quantitative reduction of goal-directed behaviour in comparison to an individual's prior level of functioning. Persistence of activity defined as the capacity to continue with a task – sometimes in the face of setbacks, high levels of difficulty or fatigue – is a crucial but understudied aspect of goal-directed behaviour. Surprisingly, it has not been investigated yet in the context of apathy. Here, we provide an overview of theoretical and experimental aspects of persistence in effort that might assist to develop methods for the investigation of persistence in human behaviour, particularly within the pathologic context of apathy.

Photoacoustic (PA) imaging of interphalangeal peripheral joints is of interest in the context of using the synovial membrane as a surrogate marker of rheumatoid arthritis. Previous work has shown that ultrasound (US) produced by absorption of light at the epidermis reflects on the bone surfaces within the finger. When the reflected signals are backprojected in the region of interest, artifacts are produced, confounding interpretation of the images. In this work, we present an approach where the PA signals known to originate from the epidermis are treated as virtual US transmitters, and a separate reconstruction is performed as in US reflection imaging. This allows us to identify the bone surfaces. Furthermore, the identification of the joint space is important as this provides a landmark to localize a region-of-interest in seeking the inflamed synovial membrane. The ability to delineate bone surfaces allows us to identify not only the artifacts but also the interphalangeal joint space without recourse to new US hardware or a new measurement. We test the approach on phantoms and on a healthy human finger.

In this research, we consider a production planning problem that determines the production timings and quantities for multiple products over a finite number of periods without violating capacity constraints. This problem is commonly referred to as the capacitated lot sizing (CLS) problem. We develop a model that explicitly considers setup times for products and different types of production capacities such as regular time and overtime. We develop a heuristic based on Lagrangian relaxation to solve this CLS problem. Computational results show that our algorithm gives reliable results while comparing solution values to lower bounds.

Low frequency dielectric relaxation has been reported for a nematic liquid crystal in the frequency range of 1 kHz to 10 MHz and in the temperature range from 25 °C to 100 °C. The optical behaviour has also been studied by measuring the refractive indices, birefringence and optical transmittance in the temperature range mentioned above. The birefringence data have been used to calculate the order parameter by Vuks’ approach, and its variation with temperature has been discussed. Transition temperatures obtained using different techniques are found to be in good agreement with each other.

Current imaging modalities are often not able to detect early stages of breast cancer with high imaging contrast. Visualizing malignancy-associated increased hemoglobin concentrations might improve breast cancer diagnosis. Photoacoustic imaging can visualize hemoglobin in tissue with optical contrast and ultrasound resolution, which makes it potentially ideal for breast imaging. The Twente Photoacoustic Mammoscope (PAM) has been designed specifically for this purpose. Based on a successful pilot study in 2007, a large clinical study using PAM has been started in December 2010. PAM uses a pulsed Q-switched Nd:YAG laser at 1064 nm to illuminate a region of interest on the breast. Photoacoustic signals are detected with a 1MHz, unfocused ultrasound detector array. Three dimensional data are reconstructed using an acoustic backprojection algorithm. Those reconstructed images are compared with conventional imaging and histopathology. In the first phase of the study, the goal was to optimize the visualization of malignancies. We performed sixteen technically acceptable measurements on confined breast malignancies. In the reconstructed volumes of all malignancies, a confined high contrast region could be identified at the expected lesion depth. After ten successful measurements, the illumination area was increased and the fluence was substantially decreased. This caused a further significant increase in PAM lesion contrast.

We present a study of the laboratory version of a time-resolved photoacoustic mammoscope built based on a parallel plate geometry. An intralipid (IL) phantom with embedded cylindrical dyed gel inhomogeneities of different sizes and optical absorptions was used to test the quality of 3D image reconstruction and ability of studied instrument to detect optical contrast between imaged objects. The temporal backward projection Fourier transform based method was used for image reconstruction. The results of this study show that width at half maximum of images obtained by the photoacoustic mammoscope correlate well with lateral profile of imaged structures and that the optical contrast between imaged objects can be measured with deviation of 35%.

Breast cancer is one of the major causes of morbidity and mortality in western women. Current screening and diagnostic imaging modalities, like x-ray mammography and ultrasonography, focus on morphological changes of breast tissue. However, these techniques still miss some cancers and often falsely detect cancer. The sensitivity and specificity for detecting the disease can probably be improved by focusing on the consequences of tumor angiogenesis: the increased microvessel density with altered vascular characteristics. In this review, various techniques for imaging breast tumor vasculature are discussed. Dynamic contrast enhanced magnetic resonance imaging is the most-used imaging modality in this field. It has a proven high sensitivity, but a low specificity and cannot be applied in all women. Moreover, it has problems with detecting ductal carcinoma in situ(DCIS). On the contrary, contrast enhanced digital mammography can detect DCIS, but requires the use of ionizing radiation. Contrast enhanced ultrasound provides real-time information about true intravascular blood volume and flow. However, this technique still has difficulties with discriminating benign from malignant tissue. Moreover, these three imaging modalities all require the injection of contrast agents. Two relatively new techniques that do not use external contrast agents are diffuse optical imaging and photoacoustic imaging. Both visualize the increased concentration of hemoglobin in malignant tissue and thereby provide a high intrinsic contrast.

The use of nanoparticles in biomedical applications is emerging rapidly. Recent developments have led to numerous studies of noble metal nanoparticles, down to the level of single molecule detection in living cells. The application of noble metal nanoparticles in diagnostics and treatment of early stage carcinomas is the subject of many present studies. Gold nanoparticles are particularly interesting for optical biomedical applications due to their biocompatibility and moreover, their enhanced absorption cross-sections. The latter is a result of surface plasmon resonance, which can be tuned by altering the shape of the nanoparticles enabling usage of the near infrared tissue transparent optical window. This paper presents a brief overview of the variety of shapes, size and surface chemistries of the gold nanoparticles used for cancer detection and treatment, as well as their effects in different tumour models that have recently been investigated, both in vitro and in vivo.

Accurate lymph node analysis is essential to determine the prognosis and treatment of patients suffering from melanoma. The initial results of a tomographic photoacoustic modality to detect melanoma metastases in resected lymph nodes are presented based on phantom models and a human lymph node. The results show melanoma metastases detection is feasible and the setup is capable of distinguishing absorbing structures down to 1 mm. In addition, the use of longer laser wavelengths could result in an image containing a higher contrast ratio. Future research shall be focused on using the melanin characteristics to improve contrast and detection possibilities.

AbstractTo establish the use of TEHDGA/isodecylalcohol/n-dodecane solvent system for actinide partitioning from HLW, the hydrolytic and radiolytic stability of the solvent was investigated. Hydrolysis of TEHDGA with nitric acid at room temperature was not observed. Radiolytic degradation was observed and found to increase with increase in absorbed dose. It was found that the presence of n-dodecane enhances the degradation of TEHDGA whereas isodecyl alcohol, the phase modifier, has no such effect. At gamma-radiation dose as high as 0.2 MGy, no significant loss of TEHDGA was observed. The degradation products were identified by GC-MS, the main products were formed by cleavage of ether and amide bonds of TEHDGA molecule. The extraction behavior of Am(III) at 4.0 M HNO3does not vary much with increase in absorbed dose, however stripping behavior is affected by the presence of acidic degradation products formed during radiolysis. The findings indicate that the solvent retains its expected extraction and stripping properties up to a high gamma-radiation dose of 0.2 MGy. Irradiated solvent was purified and made suitable for reuse by treating it with 5% w/v Na2CO3solution, basic alumina and finally by distillation at reduced pressure.

In this research, we formulate and solve a type of the capacitated lot-sizing (CLS) problem. This problem is commonly found in many manufacturing settings. Unlike a typical formulation, our formulation explicitly considers different types of production capacities such as regular time and overtime. We develop a heuristic based on Lagrangean relaxation with a decomposition scheme to solve this CLS problem. Computational results show that our algorithm gives very good results while comparing to lower bounds.

Summary: An agar-liquefying Acinetobacter species capable of utilizing agar as sole source of carbon and energy was isolated from soil samples and the culture conditions were standardized for the maximal production of extracellular agarase. The bacterium was capable of liquefying an agar-plate within 3 days of incubation and produced extracellular agarase within a short period of time (16–18 h) when grown in defined mineral salts medium. Bacterium grew in the pH range 4.0–9.0, optimal at pH 7.0; temperature 25–40 °C and optimal at 37 °C. The agarase secreted by the Acinetobacter strain was inducible by agar and not repressed by other simple sugars when supplemented along with agar in the medium. The bacterium did not require NaCl for growth or production of agarase. The bacterium did not utilize other polysaccharides like κ-carrageenan, alginate, cellulose, and CMC. The activity staining of partially purified agarase preparations after native-PAGE and SDS PAGE revealed the presence of a single zone of clearance corresponding to the molecular weight 100 kDa, suggesting that it is a monomer. Neoagarobiose was the end product of agarose hydrolysis by this enzyme. The agarase was an endo-type glycosidase and belongs to Group-III β-agarase family.

Large, colorless aggregates are observed during the induction period of a chemical oxidative polymerization of aniline in dilute aqueous acids using an ammonium peroxydisulfate oxidant. Observed for the first time by static and dynamic light‐scattering (LS) measurements, these aggregates are believed to be anilinium–peroxydisulfate ion clusters whose shape (spherical or rodlike) plays an important role in the overall morphology of the emeraldine salt formed (granular or fibrillar). The role of these aggregates in influencing the morphology of polyaniline is further evaluated under a variety of reaction conditions, for example, varying ionic strength, concentration, temperature, nitrogen substitution, and so forth.

An agar-degrading bacterium capable of utilizing agar as sole source of carbon and energy was isolated from sea water by enrichment culture technique. The bacterium was identified as Pseudomonas aeruginosaand the culture conditions were standardized for the maximal production of extracellular agarases. The bacterium grew in the pH range 5.0–11.0, optimal between pH 7.0 and 8.0; temperature between 25 °C and 37 °C, optimal at 30 °C and sodium chloride concentration 0–8% and optimal at 2% respectively. The agarases secreted by Pseudomonas aeruginosaAG LSL-11 were inducible by agar and not by any other simple sugars tested. Maximal agarase production was observed at pH 8.0, and temperature 30 °C. The bacterium had no requirement for NaCl for both growth and production of agarases. The bacterium did not utilize other polysaccharides like ĸ-carrageenan, alginate, cellulose and CMC. The activity staining of partially purified agarase preparation after native-PAGE revealed the presence of three different agarases, agarase LSL-11a, LSL-11b and LSL-11c, whose molecular weights were estimated to be 76, 64 and 46 kDa respectively.An agar-degrading bacterium capable of utilizing agar as sole source of carbon and energy was isolated from sea water by enrichment culture technique. The bacterium was identified as Pseudomonas aeruginosaand the culture conditions were standardized for the maximal production of extracellular agarases. The bacterium grew in the pH range 5.0–11.0, optimal between pH 7.0 and 8.0; temperature between 25 °C and 37 °C, optimal at 30 °C and sodium chloride concentration 0–8% and optimal at 2% respectively. The agarases secreted by Pseudomonas aeruginosaAG LSL-11 were inducible by agar and not by any other simple sugars tested. Maximal agarase production was observed at pH 8.0, and temperature 30 °C. The bacterium had no requirement for NaCl for both growth and production of agarases. The bacterium did not utilize other polysaccharides like ĸ-carrageenan, alginate, cellulose and CMC. The activity staining of partially purified agarase preparation after native-PAGE revealed the presence of three different agarases, agarase LSL-11a, LSL-11b and LSL-11c, whose molecular weights were estimated to be 76, 64 and 46 kDa respectively.

Novel nanocomposites of polyaniline dispersed with γ‐Fe2O3 nanoparticles were prepared by the in situ polymerization of aniline in the presence of ammonium peroxysulfate as an oxidizing agent. Dielectric constants of the derived composites varied with the composition of γ‐Fe2O3 present in the matrix. A maximum dielectric constant of ∼5500 was achieved when 10 mass % γ‐Fe2O3 nanoparticles were present. Nanocomposites were characterized by X‐ray diffraction, Fourier transform infrared, scanning electron microscopy, and thermal analytical techniques. Conductivity increased marginally by increasing the amount of γ‐Fe2O3 in the matrix. Dielectric constants increased 100–150 times compared to plain polyaniline matrix and were 20–40 times higher than that of γ‐Fe2O3 nanoparticles. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1868–1874, 2005

Abstract: For the determination of phosphorus in different matrices, the derivative neutron activation analysis is especially applicable to aqueous samples, since the conventional neutron activation analysis is not useful for the determination of phosphorus. Phosphorus when reacted with ammonium molybdate 4 hydrate and ammonium metavanadate forms molybdo vanado phosphoric acid. This complex is preconcentrated by extracting into methyl isobutyl ketone. The organic phase containing the molybdo vanado phosphoric acid is neutron activated and the phosphorus is determined through the activation product of 52V. Preparation of this complex, its stoichiometry, application to trace level determination of phosphorus and improved detection limit are discussed. This method was applied for the analysis of industrial effluent samples.

A number of silica supported nickel carbonate systems were studied by positron annihilation lifetime spectroscopy (PAS) and nitrogen gas adsorption method (BET) to evaluate the pore size distribution in the samples. Results show that the long-lived o-Ps component gives a pore size much smaller than the average pore radius obtained from BET analysis. This indicates that o-Ps represents the pores of smaller size in a sample with wide pore size distribution.

Positron annihilation lifetime spectroscopy was used to characterize the reentrant volume-phase-transition behavior of poly(N-isopropyl acrylamide) hydrogel in an ethanol/water mixed solvent. The polymer gel was synthesized with γ irradiation. The ortho-positronium lifetime (τ3) in the gel slowly increased with an increase in the ethanol content in the mixed solvent. τ3 was not influenced by the volume phase transition. The ortho-positronium intensity decreased with the collapse of the gel in an approximately 10% ethanol/water mixture. When swelled in pure ethanol, τ3 initially increased with the solvent amount in the gel, showing the destruction of intramolecular hydrogen bonding and the relaxation of polymer chains. The lower critical solution temperature of the gel in the 10% ethanol/water mixture was lower than that in pure water, and τ3 for various solvent contents showed behavior similar to that seen in pure solvent. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1028–1036, 2002

Formation cross sections of about forty fission products have been determined using recoil catcher technique followed by off line gamma-ray spectrometry in 7Li induced fission of 232Th at Elab= 41.9, 36.6 and 31.4 MeV. The measured data have been used to deduce charge and mass distributions. Mass distribution is found to be asymmetric at all the three energies. Cross sections of evaporation residues formed in both transfer reactions (232,233,234Pa) as well as in complete fusion (234Np), have also been measured. The measured evaporation residue cross sections and the decay probabilities of target like nuclei (233,234,235Pa) formed in the various transfer reactions, as calculated by PACE2, have been used to estimate the transfer induced fission cross sections. The data indicated that the magnitude of transfer induced fission is very small.

The concentrations and distribution of the elements, including heavy metals such as As, Ba, Br, Co, Cr, Cs, Fe, Ga, K, Mn, Na, Rb, Sc, Sr, Th and Zn, were investigated in dated sediment cores of Nainital Lake located in the Himalayan region, in Uttar Pradesh state of India, which is considered as a remote background area. The concentrations of the elements were measured by instrumental neutron activation analysis using the k₀ method. The International Atomic Energy Agency certified reference material SL-3 was used to evaluate the accuracy of the method. The normalized data for a series of elements were used to understand the source of loading. Elements like Br, Co, Cr, Fe, K, Mn and Zn show a negative correlation with increasing depth whereas elements like As, Ba, Cs, Na and Rb show a positive correlation with increasing depth. By considering the concentration for the bottom segments of the core as close to the baseline concentration, recent flux values for different elements were calculated. An increase in the flux value was observed for Br, Cr, Fe, K, Mn and Zn, which can be attributed to anthropogenic contribution in recent years.

The temperature-sensitive poly(N-isopropylacrylamide) hydrogels, prepared by γ and electron-beam (EB) irradiation, were studied using positron annihilation lifetime spectroscopy (PALS). The effect of water content in the hydrogel on the ortho-positronium (o-Ps) lifetime and intensity was investigated. The observed positronium lifetime suggests microstructural differences between γ- and EB-synthesized hydrogels. The distribution in positronium lifetime indicates nonhomogeneity in the distribution of free-volume holes in EB-synthesized hydrogels. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3462–3466, 2000

An extraction chromatographic procedure for the recovery of fission product palladium has been developed. The method utilizes Cyanex 471X (tri isobutyl phosphine sulfide, TIPS) impregnated on an inert support, Chromosorb-102. Using this method, quantitative uptake of the metal ion is achieved from nitric acid medium. Thiourea as a suitable stripping agent is suggested. Palladium was estimated spectrophotometrically using Arsenazo III as the chromogenic agent and incorporating a modification in the procedure when the aqueous medium contained thiourea.

A case of a 10-year old boy with an anterior spinal epidural hematoma in the cervical spine is presented. Subsequent to the MR examination clinical and laboratory work-up revealed the child to have a severe form of Hemophilia-A. The intraspinal bleeding was the first manifestation of this disease in the boy; the site of bleeding too was unusual. Subsequent imaging studies after treatment with Factor VIII replacement are also depicted. The pivotal role of MRI in the diagnosis of the hematoma is stressed.In a young male child with these clinical and imaging features, one should investigate the possibility of hemophilia and congenital coagulation defects

Elemental concentrations of a few medicinal leaves are determined by instrumental neutron activation analysis using the single comparator (k0) method. Data obtained for neem leaves, collected from two different places, have been used to see the effect of soil condition. The applicability of the method particularly for the simultaneous determination of Ca, Mg, V and Al in biological matrices has been evaluated in terms of the detection limit, precision and accuracy. The method was validated by analysing the NIST Standard Reference Material (SRM-1571) and it was found that the elemental concentrations measured in SRM-1571 are within ±10% of the reported values.

Heavy ion activation of natural terbium foil with 75 MeV 12C6+results in the formation of carrier-free lutetium isotopes, 165–167Lu, and their corresponding decay products, 165–167Yb and 165–167Tm, in the matrix. Carrier-free lutetium and ytterbium isotopes have been separated quantitatively from terbium bulk target matrix using HDEHP liquid cation exchanger. Radiochemically pure thulium radionuclides have been obtained after the decay of ytterbium radionuclides.

Excitation functions for evaporation residues of the system 16O + 165Ho have been measured up to 100 MeV. Recoil range distribution of long lived reaction products were measured at 16O beam energy of 100 MeV. Detailed Monte Carlo simulation of recoil range distributions of products were performed with the help of PACE2 code, in order to extract the contributions of incomplete fusion in the individual channels. The results clearly show the incomplete fusion contributions in the tantalum and thulium products. This is confirmed by the predictions of breakup fusion model of the incomplete fusion.