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Antimicrobial resistance (AMR) is considered as one of the biggest threats to modern civilization. The reviewis published with a view to provide awareness about this growing menace, which if not monitored and controlledcould lead to major public health consequences with greater economic impact. Very little data and information isavailable regarding AMR in livestock and aquaculture. An attempt was made to collate the available information onAMR subsequent to constitution of INFAAR (Indian Network on Fishery and Animals Antimicrobial Resistance) byICAR and FAO, in reference to National Action Plan on AMR by GoI in April, 2017.

Summary Background Permanent chemotherapy-induced alopecia (pCIA), for which preventive interventions remain limited, can manifest with scarring. While the underlying pathomechanisms of pCIA are unclear, depletion of epithelial hair follicle (HF) stem cells (eHFSCs) is likely to play a role. Objectives To explore the hypothesis that, besides apoptosis, eHFSCs undergo pathological epithelial–mesenchymal transition (EMT) in pCIA, thus explaining the scarring phenotype. Furthermore, we tested whether a peroxisome proliferator-activated receptor (PPAR)-γ modulator could prevent pCIA-associated pathomechanisms. Methods Organ-cultured human scalp HFs were treated with the cyclophosphamide metabolite 4-hydroperoxycyclophosphamide (4-HC). Additionally, HFs were pretreated with the agonistic PPAR-γ modulator N-acetyl-GED-0507-34-Levo (NAGED), which has previously been shown to promote K15 expression and antagonize EMT in eHFSCs. Results In accordance with anticipated hair bulb cytotoxicity, dystrophy and catagen induction, 4-HC promoted apoptosis along with increased p53 expression, DNA damage and pathological EMT in keratin 15+ (K15) eHFSCs, as evidenced by decreased E-cadherin expression and the appearance of fibronectin+ and vimentin+ cells in the hair bulge. Pretreatment with NAGED protected against 4-HC-induced hair bulb cytotoxicity/dystrophy, and apoptosis, p53 upregulation and EMT in the bulge, thereby significantly preventing depletion of K15+ human eHFSCs ex vivo. Conclusions Since a key cyclophosphamide metabolite alone suffices to damage and deplete human scalp eHFSCs by promoting apoptosis, DNA damage and EMT ex vivo, strategies to prevent pCIA need to target these pathomechanisms. Given the ability of NAGED to prevent chemotherapy-induced eHFSCs damage ex vivo, our study introduces the stimulation of PPAR-γ signalling as a novel intervention strategy for the prevention of pCIA.

Corona mortis (CMOR) is an anastomotic channel either arterial, venous or both connecting the obturator and external iliac systems excluding aberrant channels in the retropubic space. The goal of this study is to illustrate the type of CMOR via the Anterior Intrapelvic approach (AIP) which has not been studied in tandem. This descriptive observational study was performed in the Department of Anatomy, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India from January 2018 to December 2020. It is a potential culprit for significant haemorrhage in scenarios of pelvic trauma or when sectioned accidentally, augmenting difficult haemostasis behind the superior pubic ramus. Previously reported to be exclusively arterial, the venous variant has now emerged as the more frequent anastomosis. AIP was performed on 31 adult human cadavers of 62 hemipelvises to record variations and statistical analysis of retropubic anastomosis with respect to gender, weight groups and side distribution was done. Corona Mortis was observed in 50(80.6%) hemipelvises. To ramify, venous CMOR and arterial CMOR were exclusively encountered in 25(40.3%) and 10(16.10%) hemipelvises respectively. Males recorded a higher prevalence of CMOR. Despite being a frequent anastomotic variant, it is a rare entity in textbooks. CMOR can potentially alter patient outcome and have serious implications in pelvic surgeries via AIP owing to its easier accessibility. Besides, venous CMOR being more common, a venous bleed is inherently more arduous to manage in the pelvis. A larger calibre, less frequent aberrant channel could also prove to be lethal in its injury. Hence, cadaveric simulation of the technique is paramount to master the technique and to mitigate catastrophic vascular events.

Existence of variations in morphological proportions in human beings has led to the development of different values of tibio femoral angle (TFA) in different populations which is undoubtedly useful in clinical orthopaedic surgery. Meagre literature is available among Indian population. The cross-sectional study was creating baseline data of TFA among Rajasthani population of India with reasonable accuracy and also to correlate these data to radiological findings during July 2014-June 2016. The TFA (in degrees) of 500 healthy subjects from various regions of Rajasthan were measured in standing and supine positions. In addition, the TFA of 134 persons (randomly selected) from study group were also measured on roentgenogram. Subsequently both of these data were compared. The normal range of TFA angle in Rajasthani population was in between 160°-174°. TFA in standing position on right side was 170.96° (with 95% Confidence Interval (CI) = 170.24 to 171.68) and on left side was 170.14° (with 95% CI = 169.21 to 171.06). Mean TFA in supine position on right side in age group from 21 to 30 years was 167.12±6.73° and in age group from 31-40 years was 167.668±6.7°. No significant difference was observed in posture change and according to age. Statistically significant difference was observed in between radiological and gross measurement which was more in radiological than to clinical measurement of TFA (mean difference = +5.78° units) with 95% CI for the difference is (4.03°-7.53°). Higher values of tibio-femoral angle (TFA) were observed in males as compared to females and in radiological measurements.

Carrying angle is one of the secondary sexual characteristics which is important for keeping the hand away from body to improve functionality. A cross-sectional survey was conducted in Western Indian population (rural and urban population in and around Jodhpur district) during July 2014-June 2016 with the purpose of evaluating the carrying angle in apparently healthy adult and determines the range of normality according to age, sex, height, waist circumference and special reference to handedness. The carrying angle (elbow) was measured in 504 adults aged between 20-40 years (by simple random sampling) by a digital Goniometer. The subjects were in anatomical position (stand up straight, roll his/her shoulders back and the elbow was fully extended and the forearm fully supinated) while the carrying angle were taken. Carrying angle of the right side in male's 11.54°±1.29° and in female's 13.41°±1.26°, whereas these value in left side 10.21°±1.34° and 12.19°±1.44° respectively. All measurements in females are significantly higher in comparison to males (p0.001). The significant difference was observed in carrying angle according to handedness; dominant hand had higher value of carrying angle in comparison to non-dominant hand in both gender (p0.001). The height of individuals is positively correlated with the angle whereas there was no correlation was found in between age, waist circumference. The present study showed that the females have greater carrying angle than males.

To develop, a reference charts of fetal abdominal circumference and femur length in normal pregnant women by using ultrasonography for Indian population. Further comparison of our findings with data derived from different population. This retrospective cross-sectional study included 300 normal singleton pregnancies and was carried out in the department of Anatomy, All India Institute of Medical Sciences, Jodhpur (Rajasthan), India from September 2017 to April 2019. Ultrasonography measurements included Abdominal circumference (AC) and Femur length (FL). Reference charts with mean AC and FL for corresponding Gestational age (GA) in weeks were developed. Also reference centiles (10th, 50th, 90th and 95th) were derived from this model and compared with similar studies done on different population. There was no statistically significant difference in age distribution of pregnant women (p=0.87). Both AC and FL were found to have statistically significant linear relationship with advancing gestational age (p=0.0005p=0.0003 respectively). There is significant difference observed between the values obtained in present study with studies concluded on Chinese and European population. Measurement of AC and FL are used to predict gestational age of fetus by using various regression formulae, also AC is known to be good predictor of nutritional status of fetus in utero. A separate chart is required for every different population because ethnicity, nutrition and environmental factor can have impact on normal values. Therefore, a reference chart for these parameters according to Indian population standards is essential to avoid misinterpretation of data. This would help to avoid misdiagnosis of intrauterine growth retardation or macrosomia during prenatal and perinatal period.

Infertility is a growing health problem. It affects relatively large number of couples both globally as well as in India. Fertility treatment registers suggest that infertility is on increase. With the advancement in the knowledge and technology about the In Vitro fertilization (IVF) process, In Vitro fertilization success rates are improving over the time. In many cases of male-factor infertility, Intracytoplasmic sperm injection (ICSI) is the recommended treatment. The aim of this study was to estimate fertilization, implantation and pregnancy rates in ICSI cycles in association with number of attempts and sperm morphology. A total of 250 IVF-ICSI cycles were performed at a Fertility Center in Jaipur, Rajasthan, India. This cohort study was performed during 2013 to 2015. The differences in the outcomes of ICSI in association with sperm morphology and number of ICSI attempt were evaluated. Significantly higher mean was observed in fertilization rate and live birth rate with ≥5% sperm morphology 79.63% vs. 71.46% and 20% vs. 13.9% respectively). Significantly higher mean implantation rate and clinical pregnancy rate (CPR) and live birth rate were observed with attempt 3 as compared to 1 and 2 attempts. IVF success rates are improving over the time as knowledge and technology are advancing. Sperm morphology and number of attempt affect the ICSI outcomes.

The thyroid gland is an imperative endocrine gland present in the neck known commonly for its morphological variations. During routine dissection agenesis of the isthmus of the thyroid gland was observed with levator glandulae thyroidea extending from both the lateral lobes with stout stalks of pyramidal lobes bilaterally. The Levator glandulae thyroidea is a fibro-musculo-glandular band. usually, present unilaterally or extending from isthmus connecting the pyramidal lobe of the thyroid gland to the hyoid bone. The site of the isthmus is often associated with anastomosis of vessels supplying thyroid gland but strikingly no such anastomosis was observed. The presence of such variant of levator glandulae thyroidea with agenesis of the isthmus is a rare finding and knowledge of such topographical anatomical variations is crucial for understanding associated pathologies related to the thyroid gland and modus operandi in their management.

To create a reference chart for estimated fetal weight (EFW) in normal pregnancy for use in Indian population and compare it with reference chart from other population. This retrospective cross-sectional study included 300 normal singleton pregnancies coming for routine antenatal ultrasonography examination and was carried out at All India Institute of Medical Sciences, Jodhpur from September 2017 to April 2019. Ultrasonographic measurements included fetal biparietal diameter (cm), head circumference (cm), abdominal circumference (cm) and femur length (cm). Estimated fetal weight was calculated by using Hadlock algorithm which is already fed into ultrasonography machine. Reference chart with mean EFW for corresponding Gestational age (GA) in weeks was developed. Also Reference centiles (10th, 50th, 90th and 95th) were derived from this model. There was no statistically significant difference in age distribution of pregnant women (p=0.87). Statistically significant linear relationship found between EFW and advancing gestational age (p=0.0004). Maximum gain in EFW (34.05%) was observed after second trimester (28 week). Maximum and minimum fetal weight at 38 weeks of GA in our study found to be 3389 grams and 2567 grams respectively, which has significant difference. This could be due to huge difference in socio-economic and nutritional status among Indian population which might have impacted on maternal and fetal health. Estimated fetal weight was found to be at lower range in Indian population compared to reference chart developed into western population. Fetal weight to their corresponding GA is an important factor in determining growth and development in fetus. In normally developing fetus the EFW has linear correlation with advancing GA. A separate reference chart is required for every different population because ethnicity, nutrition and environmental factor can have impact on normal EFW values. This would help to avoid misdiagnosis of intrauterine growth retardation or macrosomia in fetuses and hence unnecessary medical interventions can be prevented during prenatal and perinatal period.

Fecal samples (225) from apparently healthy pigs were analysed for E. coli isolation. Multidrug-resistant (MDR) isolates (42) were identified from 225 E. coli isolates. Forty isolates exhibited extended-spectrum beta-lactamases (ESBL) phenotype harbouring single to multiple-sized plasmids (1 kb to ≥ 25 kb). Overall blaTEM (85.7%) was the commonest genotype, followed by blaCTX-M (61.9%), blaOXA (17%) and blaSHV was not recovered. Other antimicrobial resistant genes (ARGs) identified were sul2 (100%), strA (95.2%), tetA (92.9%), sul1 (76%), aadA (71.4%), tetB (50%), cat (42.9%) and aac(3)IV (26.2%). Plasmid-mediated quinolone resistance (PMQR) positive strains totalled to 59.5% for qnrB, 19.04% for qnrS but qnrA was not detected. Integron genes were detected either singly or combined: intI1 (76.2%), intI2 (26.2%). Conjugation experiment was successful for 4 ESBL producers. The present study detected higher carriage of ESBL producing E. coli in pigs, and highlights the dominance of resistance and integron genes circulating in MDR E. coli from swine of northeast India, posing a threat of horizontal gene transfer.

Background Lesions of the sinonasal area are varied, but they mostly present as polypoid masses which require meticulous work-up to reach at the most probable diagnosis. Objective Analysis of polypoid sinonasal masses in terms of etiology, clinical presentations, brief demographic profile, clinico-histologic correlate where possible, and follow-up results. Method In this descriptive, longitudinal study, 198 patients with polypoid sinonasal masses attending the otolaryngology clinic of a tertiary teaching institute were selected using proper selection criteria and analyzed through a pre-set proforma and algorithm for a diagnostic work-up (that included histopathology where necessary). Result Common presentations were nasal obstruction (~89%), discharge (~70%) and hyposmia (~22%). Though nearly 87% was clinically benign and 8% indeterminate, therapeutic and diagnostic interventions (including histopathology) showed 91% truly benign, of which polyposis formed the bulk. Sensitivity of clinical detection was 75% for benign lesions and 62% for malignancies. Diagnosis depended on histopathology in 52.52% cases, including the clinically malignant, the "grey zone", and more than 40% of the clinically benign lesions. There was male predilection (2.16 for benign lesions and 1.57 for malignant), rural preponderance, and above 60% of the patients were within 50-70 years. There was ~26% recurrence in the follow-up period of a minimum of one year, predominantly in polyposis (29.55%) and malignancies (~39%). Conclusion Presentations of polypoid sinonasal masses are variable, etiology of which is mostly benign. Proper clinico-histologic correlate is necessary for correct diagnosis. A low threshold of suspicion is required because of this variability, necessitating follow-up for further evaluation.

A theoretical study has been carried out to find the performance of a rotary kiln in a cement manufacturing industry, where PID controller has been used to control the quality of the clinker. This is done by finding the transfer function, steady state errors due to application of different types of input signals, such as unit step, unit ramp, and parabolic and frequency response of the whole system. The overall gain of the system is found out and numerical calculations and results are simulated using ‘MATLAB’ software.

For the last five decades, electronic devices matured enough as the transistor size shrunk considerably. There by a new paradigm of ultra small scale device technology appeared and fuelled post CMOS device research. Consequently a classical manifestation of the quantization of electron charge evolved which is referred as Coulomb blocked in single Electronics Technology. This new technology ushered numerous figure of merit in nm scale electronics and soon single electronics was encoded to design logic circuits. But empirical studies revealed the limitations of room temperature based single electronics fabrication. Later on by amalgamating single electronics with conventional CMOS, addressed the limiting factors of single electronics fabrication. The new device principle is attributed as “Hybrid CMOS Single Electronics”. Since the last decade this hybrid topology is considered to design logic circuits similar to CMOS. Here the authors integrate classical CMOS with the uprising single electronics to model an expandable hardware and study its effectiveness to meet the current needs.

India is confronted with many hygiene problems in urban areas that are related to animal populations. While some of these issues have been present for many years, others are only now emerging. A livestock census in 2003 and another in 2007 revealed that populations of crossbred cattle, goats and poultry are all increasing in urban areas, since this enables easy market access, which, in turn, reduces transportation costs and adds to profits. The canine population has increased along with the human population, largely due to a lack of control measures such as impounding stray animals and euthanasia. These increases in populations of both food-producing animals and stray animals in cities exacerbate such public health hazards as the transmission of zoonoses, vector-borne diseases, occcupational health hazards and environmental pollution, as well as compromising animal welfare. At present, public health hazards due to urban animal husbandry practices are considerably under-estimated. To improve veterinary-related urban hygiene and to facilitate livestock production operations in urban areas, there is an urgent need to develop sound, science-based strategies enforced through stringent regulations. The use of One Health teams may provide an answer to these highly integrated public health problems.

Veterinary public health (VPH) assumes huge significance in developing countries such as India. However, the implementation of VPH services throughout the country is still in its infancy. From 1970 onwards, many institutes, national and international organisations, professional societies, policies and personalities have contributed towards the development of VPH in India. Nevertheless, there is an urgent need to develop VPH still further as there are many issues, such as high population density, the re-emergence of zoonotic pathogens, environmental pollution and antimicrobial resistance, that require attention. The time has surely come to involve all stakeholders, ranging from primary producers (e.g., farmers) to policy-makers, so as to garner support for the holistic implementation of VPH services in India. To improve VPH activities and services, science-based policies enforced through stringent regulation are required to improve human, animal and environmental health. The emergence of the 'One Health' concept has ushered in new hopes for the resurrection of VPH in India. Applying tools such as the World Organisation for Animal Health (OlE) Day One Competencies and the OlE Tool for the Evaluation of Performance of Veterinary Services (PVS Tool) is essential to improve the quality of national Veterinary Services and to identify gaps and weaknesses in service provision, which can be remedied to comply with the OlE international standards. VPH initiatives started modestly but they continue to grow. The present review is focused on the current status and future needs of VPH in India.

In this study, 241 serum samples from individuals exposed to brucellosis were subjected to the Rose Bengal plate test (RBPT); the titre was estimated by standard tube agglutination test (STAT), with positive > or = 80 IU/ml. Randomly selected sera (n = 81) were analysed by complement fixation test (CFT): titre > or = 1:4 was considered positive. Of 241 sera subjected to RBPT and STAT, 177 were negative in both tests; 5 samples tested negative by RBPT but positive by STAT. None was positive by RBPT and negative by STAT. Of 81 sera subjected to CFT, 23 (28.4%) were positive. Both RBPT and CFT found 18 samples positive; 5 samples were positive by CFT and negative by RBPT. Comparison of STAT with CFT showed 13 samples positive by STAT but negative by CFT, and 4 positive by CFT but negative by STAT. The sensitivity and specificity of STAT were 82.6% and 77.6%, respectively, with CFT as gold standard. No test is perfect, and the clinical history coupled with a combination of two or more tests will reduce diagnostic errors.

The present investigation was undertaken to study the incidence and antibiogram of enterotoxigenic Bacillus cereus in raw meats and meat products. B. cereus was isolated from 97 (37.45%) of the 259 samples analyzed. Recorded incidences of B. cereus from chicken, chevon, mutton, meat products and swab samples were 33.33, 37.20, 39.47, 51.85 and 26.08%, respectively. Screening of isolates by multiplex polymerase chain reaction revealed the overall distribution of various enterotoxin genes hblD, hblA, hblC, nheA, nheB, nheC, cytK and entFM as 64.94, 64.94, 68.04, 97.83, 95.87, 93.81, 65.98 and 100%, respectively. Sensitivity of isolates to a panel of 10 antimicrobial agents revealed gentamicin (100%), ciprofloxacin (98.97%), chloramphenicol (89.69%) and streptomycin (85.56%) to be the most effective antibiotics, while the highest resistance was noted against penicillin G (91.75%). A relatively higher incidence of B. cereus in meat products, with the majority of isolates harboring all the enterotoxin genes and detection of multiple antibiotic resistant strains, pose a potential public health threat. PRACTICAL APPLICATION The consumption of meat and meat products contaminated with Bacillus cereus is one of the important causes of foodborne illnesses throughout the world. A high incidence of B. cereus in meat, particularly in ready-to-eat meat products, poses a serious health threat to the consumers. One of the important concerns regarding this is to determine the source of contamination in the meat in order to prevent it. Moreover, very limited data are available regarding the enterotoxin gene profile and antibiogram of B. cereus strains isolated from such kind of foods. B. cereus isolated from meat and meat products was found to be resistant to multiple antibiotics, strongly hemolytic and showed the presence of at least one enterotoxigenic gene. Therefore, the presence of large number of enterotoxigenic and multiple antibiotic resistant B. cereus strains in the meat and meat products must be considered a potential health hazard.

The dielectric permittivity of nanocrystalline cadmium–zinc ferrite prepared by the ball milling method has been investigated within a temperature range 77≤T≤300 K in presence of a magnetic field up to 1 T and in the frequency range 20 Hz–1 MHz. The dielectric permittivity follows the power law e / ( f )∝ T n where the temperature exponent ‘ n ’ is found to be frequency dependent. The dielectric properties of the samples have been analyzed in terms of electric modulus vector. The dielectric relaxation has been explained by interfacial polarization. The variation of the relaxation time with temperature indicates the presence of two different activation energies. The ac magnetoconductivity is positive for the milled sample and becomes negative for the unmilled sample. This behavior can be explained in terms of grain and grain boundary contribution to impedance of the samples.

The transport properties of nonstoichiometric nickel ferrite nanoparticles synthesised by the co-precipitation method followed by mechanical milling is reported here. The particle size of ferrite phase in the ball milled samples is found to be ranging from ∼3.5 nm to ∼14 nm but in the un-milled sample it becomes ∼75 nm. A minimum in the conductivity has been observed in dc conductivity versus temperature variation while the activation energies of all the samples show an increasing trend with increasing milling time. The alternating current conductivity has been described by power law σ ′( f , T ) ∝ f s T n . The frequency exponent ‘ s ’ shows anomalous behavior, while the magnitude of the temperature exponent ‘ n ’ strongly depends on frequency. The dc and ac magnetoresistivities have been observed to be negative. Although the grain boundary contribution is predominated over grain contribution, the magnitude of both grain and grain boundary resistances reduce to lower value under the application of magnetic field.

Nanocrystalline cadmium-zinc ferrite samples were prepared by ball milling method and its electrical transport property were investigated within a temperature range 77 K ≤ T ≤ 300 K in presence of a magnetic field up to 1T and in a frequency range 20 Hz to 1 MHz. The investigated samples follow a simple hopping type charge transport. The dc magnetoconductivity has been explained in terms of orbital magnetoconductivity theory. The alternating current conductivity follows the universal dielectric response σ'/(f) ∝ Tnfs. The values of ‘s’ have a decreasing trend with temperature. The temperature exponent ‘n’ depends on frequency. The dielectric permittivity of the samples depends on the grain resistance and interfacial grain boundary resistance. The ac magnetoconductivity is positive which can be explained in terms of impedance of the sample.

The synthesis of polyaniline (PANI) containing different carbon nanotubes (CNTs) by in situ polymerization is reported in this study. The samples were characterized by X-ray diffraction and scanning electron microscopy. Fourier transform infrared and ultraviolet–visible spectroscopy were used to determine the change in structure of the polymer/CNT composites. Thermogravimetric analysis showed that the composites had better thermal stability than the pure PANI. Photoluminescence spectra showed a blueshift in the PANI–single-walled nanotube (SWNT) composite. Low-temperature (77–300 K) electrical transport properties were measured in the absence and presence of a magnetic field up to 1 T. Direct-current conductivity exhibited a nonohmic, three-dimensional variable range hopping mechanism. The room-temperature magnetoconductivity of all of the investigated samples except the PANI–SWNT composite were negative; however, it was positive for the PANI–SWNT composite, and its magnitude decreased with increasing temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polyaniline/multiwalled carbon nanotube (PANI/MWNT) composites were prepared by in situ polymerization. Scanning electron microscope, X-ray diffraction, Fourier transform infrared, Uv-Visible spectroscopy, Fluorescence spectrophotometry were done to characterize the PANI/MWNT composites. Thermal stability was measured by thermogravimetry analysis. The thermal stability of PANI/MWNT composites becomes higher than PANI. Electrical transport properties of different PANI/MWNT composites were investigated in the temperature range 77 ≤ T ≤ 300 K with and without magnetic field up to 1 T. The dc resistivity of PANI/MWNT composites shows different behavior compared to the sample without MWNT. The room temperature dc magnetoconductivity of the samples is negative; however, its sign changes to positive by lowering the temperature, which has been explained by hopping type charge transport. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1767–1775, 2010

Polyaniline (PANI) was synthesized by the well-known oxidative polymerization of aniline with ammonium peroxodisulfate as the oxidant. The morphological, structural, thermal, optical, magnetic, and electrical properties were characterized with scanning electron microscopy, X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, ultraviolet–visible spectroscopy, room-temperature magnetic measurements, and low-temperature electrical transport measurements by the standard four-probe method. Greater thermal stability and crystallinity were observed in doped PANI versus pure PANI. Magnetic measurements showed that the magnetic susceptibility was field-dependent. Positive and negative susceptibility values were observed. This may have been due to the interactions of magnetic ions among interchains or intrachains of the polymer matrix. The alternating-current (ac) conductivity was measured in the temperature range of 77–300 K in the frequency range of 20 Hz to 1 MHz. The frequency-dependent real part of the complex ac conductivity was found to follow the universal dielectric response: σ′(f) ∝ fs [where σ′(f) is the frequency-dependent total conductivity, f is the frequency, and s is the frequency exponent] The trend in the variation of the frequency exponent with temperature corroborated the fact that correlated barrier hopping was the dominant charge-transport mechanism for PANI–CoCl2. An anomalous dependence on temperature of the frequency exponent was observed for PANI–CuCl2. This anomalous behavior could not be explained in terms of existing theories. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Nanocrystalline Mg–Zn ferrite is prepared by ball milling the stoichiometric powder mixture of MgO, ZnO and α-Fe 2 O 3 . The ternary Mg–Zn ferrite phase may not be obtained by heat treatment of the stoichiometric powder mixture of the oxides. The particle size of ferrite phase in the ball milled samples remains almost unaltered (∼3 nm) and that of in annealed samples increases up to ∼330 nm. Alternate current conductivity and dielectric properties of nanocrystalline Mg–Zn ferrite in the temperature range 77≤ T ≤300 K, applying magnetic field up to 1 T in the frequency range 20 Hz–1 MHz, are being reported. The frequency dependence of conductivity has been described by power law σ′( f , T )∝ f s and the frequency exponent ‘ s ’ is found to be anomalous temperature dependent. A detailed analysis of the temperature dependence of the universal dielectric response parameter ‘ s ’ revealed that the correlated barrier hopping is the dominating charge transport mechanism. The real part of the dielectric permittivity at a fixed frequency was found to follow the power law e ′( f , T )∝ T n and the magnitude of the temperature exponent ‘ n ’ strongly decreases with increasing frequency. The dielectric permittivity shows a large degree of dispersion at low frequency, but rapid polarization at high frequencies, which can be interpreted by the Maxwell-Wagner capacitor model. The temperature dependence of resistance due to grain and grain boundary contribution exhibits two activation regions. The observed positive ac conductivity may be due to the change of grain and grain boundary resistances caused by the magnetic field.

We report a comprehensive study of electrical transport properties of stoichiometric (Mg,Ni)-ferrite in the temperature range 77 ≤ T ≤ 300K, applying magnetic field upto 1T in the frequency range 20 Hz-1 MHz. After ball milling of MgO, NiO and ?-Fe2O3 and annealing at 1473K, a (Mg,Ni)-ferrite phase is obtained. The temperature dependency of dc resistivity indicates the prevalence of a simple hopping type charge transport in all the investigated samples. The activation energy decreases by annealing the samples by 1473K. The dc magnetoresistivity of the samples is positive, which has been explained by using wave function shrinkage model. The frequency dependence of conductivity has been described by power law and the frequency exponent ‘s’ is found to be anomalous temperature dependent for ball milling and annealing samples. The real part of the dielectric permittivity at a fixed frequency was found to follow the power law ?/(f,T) ? Tn. The magnitude of the temperature exponent ‘n’ strongly depends on milling time and also on annealing temperature. The dielectric permittivity increases with milling and also with annealing. An analysis of the complex impedance by an ideal equivalent circuit indicates that the grain boundary contribution is dominating over the grain contribution in conduction process.

Electrical transport properties of nanocrystalline zinc ferrite were investigated in the temperature range 77⩽ T ⩽300 K, applying magnetic field upto 1 T in the frequency range 20 Hz–1 MHz. The DC conductivity follows a simple hopping type charge transport. The DC magnetoresistivity of the samples is negative, which has been explained by using tunnelling theory of magnetoresistivity. The AC conductivity was found to follow the universal dielectric response σ ′( f )∝ T n f s . The value of s is found to be weak temperature dependent for T T >200 K. The temperature exponent, n strongly depends on frequency and range of temperature. The dielectric permittivity increases with decreasing particle size, which has been interpreted by the Maxwell Wagner capacitor model. Magnetic field dependence AC conductivity shows a positive variation. A firm theoretical explanation of magnetic field dependence of AC conductivity is still lacking. The different physical parameters were calculated from the experimental data.

Powder precursors lithium aluminosilicate (LAS) of low expansion characteristics were synthesized by following the wet interaction technique in the hydroxyhydrogel form using lithium carbonate (Li2CO3), hydrated aluminium nitrate [Al(NO3)3·9H2O], fume silica (SiO2) and zirconium oxychloride (ZrOCl2·8H2O). Dilatometry, X-ray diffraction (XRD), IR analysis, Scanning Electron Microscopy (SEM) and Image analysis were done to study sintering, characteristics phase transformation and microstructure on the sintered specimens. ZrO2 was found to promote the formation of β-eucryptite, and grain size of the sintered specimens could be related to the amount of ZrO2 present in the starting powder precursor. The thermal expansion characteristics were also found to be strongly influenced by ZrO2 content in the specimens.

A powder precursor in the form of hydroxyhydrogel was prepared for the reaction sintering in the h-BN–mullite composite system. The powder precursor contains all the essential elements for the formation of the composite. Characterization of the powder precursor indicated the presence of Al 3+ in predominantly hexacoordinated state. The powder precursor yielded consolidated BN–mullite composite formed during heat treatment of pressed compact in ambient gas atmosphere.

Aluminium hydroxide as a powder precursor for making advanced ceramic materials such as yttrium aluminium garnet (YAG) was prepared from aluminium nitrate and ammonium hydroxide by two different procedures and was analyzed for determining its physico-chemical characteristics. It was observed that through the end products were essentially Al(OH)3, they differ in their physico-chemical properties. Rate constants evaluated by thermal analysis were compared and the differences observed were explained in terms of structural parameters by FTIR and related analysis.

Powder precursors of different compositions in the system Li2O–Al2O3–SiO2 were prepared in the hydroxy-hydrogel form by wet interaction technique in aqueous medium for ultimate synthesis of low expansion ceramics. Properly processed powder precursors were characterized. It was found that the powder precursor produced by this process was in meta-stable state with the aluminium in the tetrahedral as well as in the octahedral co-ordination sites. The confirmation of this finding was made by IR analysis of the prepared powder precursors as well as the heat treated samples. It was further found that the complete dehydroxylation did not occur even after heat treatment at 700 °C. The XRD analysis of the samples, when heat treated at 700 °C confirmed the detection of β-spodumene phase and the formation of this phase was almost complete when the samples were heat treated at 1000 °C.

Lithium aluminosilicate powder precursors of compositions Li 2 O:Al 2 O 3 :SiO 2 as 1:1:2; 1:1:2.5 and 1:1:3 were prepared in the hydroxy hydrogel form by wet interaction technique in aqueous medium followed by sintering for ultimate synthesis of low expansion ceramics. Phases formed in the sintered specimens were analyzed by XRD technique. Thermal expansion of the specimens sintered at 1100, 1200 and 1300 °C were also measured. It was found that β-spodumene, lithium aluminum oxide and silica were the predominat phases in all the specimens. Sintering was optimum up to 1200 °C beyond which no further noticeable shrinkage was observed. The sintered specimens remained highly porous even after firing at 1300 °C, whose bulk density and apparent porosity were in the range of 1.25–1.42 g/cm 3 and 43–48%, respectively. Thermal expansion characteristics and density of the sintered specimens were found to be primarily related to the composition of the phases formed during sintering. A porous low expansion ceramic monolith could be prepared using the present technique.

UPS inverters typically employ low pass, LC filters in the output stage for proper voltage regulation. The present paper explores a step by step comparative analysis by using an active damping control structure to provide enhancement in UPS performance without any increase in the value of resistance of LC filter. Simulation results in MATLAB environment are presented to confirm upon the point.

Hexose Utilization and Glycogen Synthesis by Setaria cervi (Nematoda)

The effect of dimecron, an organophosphorus insecticide, on developmental alterations and histopathological damage was determined in the developing chick embryo. The insecticide was administered at two different doses (25 microg and 35 microg) into the egg yolk through a pore into the equatorial region at day 0 of incubation. Significant abnormalities in relation to organogenesis and overall retardation in growth were noted in the insecticide-treated embryos. Histopathological study of the treated whole embryo showed abnormal features in the formation of different vital organs. The liver and kidney were severely affected by the pesticide at both doses. Based upon these findings it may be concluded that dimecron does play a role in producing embryotoxicity at different stages of embryogenesis.