Assessment of fluoride level in groundwater and prevalence of dental fluorosis in Didwana block of Nagaur district, Central Rajasthan, India

BACKGROUND

In India, for the high concentration of fluoride in groundwater, people are at risk of dental fluorosis. The problem is common in various states of India. The condition in Rajasthan is worse where all districts have such a problem.

OBJECTIVE

To study the fluoride concentration in groundwater and prevalence of dental fluorosis in Didwana block of Nagaur district, Central Rajasthan, India.

METHODS

The fluoride concentration in water of 54 villages was measured electrochemically, using fluoride ion selective electrode. Dental fluorosis was assessed in 1136 people residing in study area by Dean's classification for dental fluorosis.

RESULTS

The fluoride concentration in groundwater in studied sites ranged from 0.5 to 8.5 mg/L. The concentration of fluoride was more than the maximum permissible limit set by WHO and Bureau of Indian Standards (1 mg/L) in 48 groundwater sources. Of 1136 people studied, 788 (69.4%; 95% CI: 66.7%-72.1%) had dental fluoros---252 had mild and 74 had severe dental fluorosis.

CONCLUSION

High level of fluoride in drinking water of Didwana block of Nagaur district, Central Rajasthan, India, causes dental fluorosis in most people in the region and is an important health problem that needs prompt attention.

ADHD matures: time for practitioners to do the same?

Attention deficit and hyperactivity disorder (ADHD) is not restricted to children. Abundant evidence from follow-up studies accumulated since the 1970s supports the concept of ADHD in adulthood. Genetic research points to a heritability of 76%, and neuroimaging studies have reported structural and functional brain abnormalities in patients with ADHD. Contrary to popular belief, ADHD is not a culturally bound disorder and has been described worldwide. ADHD has a cost for society, as adults with this disorder suffer from increased rates of unemployment and psychiatric comorbidity, including substance use disorders. Studies undertaken in forensic populations describe high rates of ADHD in these groups, particularly amongst young offenders. One of the main issues in the diagnosis of ADHD in the adult is the fact that most clinicians have not been educated to diagnose and treat ADHD. Effective pharmacological treatments for ADHD are available and should be prescribed for these patients. The National Institute for Health and Clinical Excellence (NICE) and the British Association for Psychopharmacology (BAP) guidelines established a benchmark for service development required to treat ADHD adequately in the adult population. However, the implementation of new services has been slow. More resources are needed to effectively assess and treat ADHD in the adult.

Fluoride in the drinking water of Nagaur tehsil of Nagaur District, Rajasthan, India

Fluoride concentration of groundwater samples from 100 villages of Nagaur tehsil was determined, 85 villages were found to have fluoride concentration more than 1.5 mg/L. The maximum fluoride concentration was recorded 6.6 mg/L in groundwater of Singhani village, while the minimum was recorded in Kurchhi village. As per the desirable and maximum permissible limit for fluoride in drinking water, determined by World Health Organization, the groundwater of about 85 villages of the studied sites is unfit for drinking purpose.

Experimental realization of decoherence-free subspace in neutron interferometry

A decoherence-free subspace (DFS) is an important class of quantum-error-correcting (QEC) codes that have been proposed for fault-tolerant quantum computation. The applications of QEC techniques, however, are not limited to quantum-information processing (QIP). Here we demonstrate how QEC codes may be used to improve experimental designs of quantum devices to achieve noise suppression. In particular, neutron interferometry is used as a test bed to show the potential for adding quantum error correction to quantum measurements. We built a five-blade neutron interferometer that incorporates both a standard Mach-Zender configuration and a configuration based on a DFS. Experiments verify that the DFS interferometer is protected against low-frequency mechanical vibrations. We anticipate these improvements will increase the range of applications for matter-wave interferometry.

Engineering broad-spectrum resistance against RNA viruses in potato

RNA silencing technology has become the tool of choice for inducing resistance against viruses in plants. A significant discovery of this technology is that double-stranded RNA (dsRNA), which is diced into small interfering RNAs (siRNAs), is a potent trigger for RNA silencing. By exploiting this phenomenon in transgenic plants, it is possible to confer high level of virus resistance by specific targeting of cognate viral RNA. In order to maximize the efficiency and versatility of the vector-based siRNA approach, we have constructed a chimeric expression vector containing three partial gene sequences derived from the ORF2 gene of Potato virus X, Helper Component Protease gene of Potato virus Y and Coat protein gene of Potato leaf roll virus. Solanum tuberosum cv. Desiree and Kuroda were transformed with this chimeric gene cassette via Agrobacterium tumefaciens-mediated transformation and transgenic status was confirmed by PCR, Southern and double antibody sandwich ELISA detection. Due to simultaneous RNA silencing, as demonstrated by accumulation of specific siRNAs, the expression of partial triple-gene sequence cassette depicted 20% of the transgenic plants are immune against all three viruses. Thus, expression of a single transgene construct can effectively confer resistance to multiple viruses in transgenic plants.

PCR-Based Identification and Characterization of Fusarium sp. Associated with Mango Malformation

Mango malformation is the most serious disease of mango causing considerable damage to the mango orchards worldwide. It is a major threat for mango cultivation in north Indian belt. In recent years, Fusarium sp. is finding wide acceptability in scientific community as a causal agent of this disease. However, little information is known about the variability in Fusarium isolates from malformed mango tissues. Therefore, the major objective of present study was the identification and analysis of genetic diversity among Fusarium isolates collected from malformed mango tissues. Two texon selective primers, ITS-Fu-f and ITS-Fu-r, were used for quick identification of Fusarium spp. The fungal genomic DNA was extracted from using CTAB method and was utilized as template for PCR amplification. Total 224 bands were amplified by 18 RAPD primers at an average of 12.44 bands per primer. The size of the obtained amplicons ranged from 0.264 kb (minimum) to 3.624 kb (maximum). Data scored from 25 isolates of Fusarium sp. with 18 RAPD primers were used to generate similarity coefficients. The similarity coefficient ranged from 0.17 to 0.945. Based on DNA fingerprints, all isolates were categorized into two major clusters. This study indicated a wide variability among different isolates of Fusarium.

High performance organic phototransistor based on regioregular poly(3-hexylthiophene)

We fabricated solution processed organic phototransistors (OPT) by drop casting regioregular poly 3-hexylthiophene (P3HT) from three different solvents: p-xylene, dichlorobenzene and chloroform. The best performance was obtained for films drop-casted from p-xylene with a maximum photosensitivity (P) of 3.8 x 10(3) and responsivity (R) of 250 A W(-1) under white light illumination. For films deposited from dichlorobenzene and chloroform the values of P were 1.1 x 10(3) and 30, respectively, while the values of R were 150 and 35, respectively. The maximum responsivity value reported here is at least one order of magnitude higher than that of previously reported solution processed OPT devices. By analyzing the absorption spectra of different films, we conclude that the better device performance of OPT from p-xylene is due to better crystallinity of P3HT. Demonstration of high performance OPTs is a significant step forward in integrating these devices in various optoelectronic circuits.

Fossil evidence for the origin of aquatic locomotion in archaeocete whales

Recent members of the order Cetacea (whales, dolphins, and porpoises) move in the water by vertical tail beats and cannot locomote on land. Their hindlimbs are not visible externally and the bones are reduced to one or a few splints that commonly lack joints. However, cetaceans originated from four-legged land mammals that used their limbs for locomotion and were probably apt runners. Because there are no relatively complete limbs for archaic archaeocete cetaceans, it is not known how the transition in locomotory organs from land to water occurred. Recovery of a skeleton of an early fossil cetacean from the Kuldana Formation, Pakistan, documents transitional modes of locomotion, and allows hypotheses concerning swimming in early cetaceans to be tested. The fossil indicates that archaic whales swam by undulating their vertebral column, thus forcing their feet up and down in a way similar to modern otters. Their movements on land probably resembled those of sea lions to some degree, and involved protraction and retraction of the abducted limbs.

Pulse compression of harmonic chirp signals using the fractional fourier transform

In ultrasound harmonic imaging with chirp-coded excitation, a harmonic matched filter (HMF) is typically used on the received signal to perform pulse compression of the second harmonic component (SHC) to recover signal axial resolution. Designing the HMF for the compression of the SHC is a problematic issue because it requires optimal window selection. In the compressed second harmonic signal, the sidelobe level may increase and the mainlobe width (MLW) widen under a mismatched condition, resulting in loss of axial resolution. We propose the use of the fractional Fourier transform (FrFT) as an alternative tool to perform compression of the chirp-coded SHC generated as a result of the nonlinear propagation of an ultrasound signal. Two methods are used to experimentally assess the performance benefits of the FrFT technique over the HMF techniques. The first method uses chirp excitation with central frequency of 2.25 MHz and bandwidth of 1 MHz. The second method uses chirp excitation with pulse inversion to increase the bandwidth to 2 MHz. In this study, experiments were performed in a water tank with a single-element transducer mounted coaxially with a hydrophone in a pitch-catch configuration. Results are presented that indicate that the FrFT can perform pulse compression of the second harmonic chirp component, with a 14% reduction in the MLW of the compressed signal when compared with the HMF. Also, the FrFT provides at least 23% reduction in the MLW of the compressed signal when compared with the harmonic mismatched filter (HMMF). The FrFT maintains comparable peak and integrated sidelobe levels when compared with the HMF and HMMF techniques.

The electronic transport properties of ternary Cd(1-x)Zn(x)S nanowire networks

We present the electronic transport characteristics of ternary alloy Cd(1-x)Zn(x)S nanowire networks in the dark and under white light illumination. Compared to the negligible dark current, we observed a photocurrent enhancement of up to four orders of magnitude at an intensity of 460 mW cm(-2). The time constant of the dynamic photoresponse is approximately 5 s. The current-voltage characteristics at different intensities show Ohmic behavior at low bias and space charge limited conduction (SCLC) at higher bias voltages. The SCLC behavior and slow time response indicate that the charge transport is dominated by tunneling at the percolating inter-nanowire junctions.

Determination of natural radioactivity in building materials used in the Karachi area by γ-ray spectrometry and INAA

Samples of sand, stone and manufactured building materials collected from Karachi area have been analyzed for the primordial natural radionuclides 238U, 232Th and 40K using γ-ray spectrometry. The uranium and thorium contents have also been determined by instrumental neutron activation analysis (INAA). The specific activities in these materials, having a radium equivalent activity less than 370 Bq kg–1, when evaluated for radiological effects show that all materials meet the external γ-ray dose limitation of 1.5 mSv y–1. The γ-ray spectrometric and INAA techniques complemented each other well in this study.

Fission spectrum averaged cross section measurements of some neutron threshold reactions of relevance to medical radionuclide production

A resume is given of radiochemical measurements of nuclear reaction cross sections relevant to the production of some medically important radionuclides carried out at PINSTECH during the last decade. Systematic studies on fission neutron spectrum averaged cross sections of several threshold reactions, like (n, 2n), (n, p) and (n, α), on titanium, ruthenium, europium and dysprosium for the production of 45Ti, 96Tc, 153Sm and 153Gd are described.

Radiochemical neutron activation analysis of trace impurities in high purity titanium and tungsten

Rapid radiochemical neutron activation analysis (RNAA) procedures were developed and employed to the determination of 36 trace impurities in high purity titanium and tungsten. Anion–exchange column chromatography procedures were developed for the sequential group chemical separation of various elements, which helped in reducing the spectral interferences and improving the sensitivity of the method. The procedure is simple and requires a very short time to separate the elements in three groups for radiometric assay. To determine very low contents of uranium and thorium, 239Np and 233Pa as activation products were separated using anion–exchange and coprecipitation methods. The impurity contents were found to be low; therefore, their deleterious effects would be negligible.

Measurement of fission neutron spectrum averaged cross sections of some threshold reactions on zirconium: Production possibility of no-carrier-added 90Y in a nuclear reactor

Employing the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy fission neutron spectrum averaged cross sections were measured for several (n, p) and (n, α) reactions on isotopes of zirconium; our measurements constitute the first systematic study. The special interest was in the investigation of the 90Zr(n, p)90Y reaction for the production of no-carrier-added 90Y in a nuclear reactor. At a fast neutron flux density of 7.5 × 1013 cm−2 s−1 and an irradiation time of 120 h, using 100% enriched 90Zr target 0.548 GBq of no-carrier-added 90Y per batch could be produced. The method is thus suitable for medium-scale production of this radionuclide.

Quantitative analysis of ancient Chinese ceramic using k 0-instrumental neutron activation analysis

IAEA-CU-2006-06 (ancient Chinese ceramic) has been analyzed by k 0-INAA and the results for 31 elements are reported. Measurement on Si was done via the (n,p) reaction. The results of 23 elements are within ±10% of the target values and for 2 elements data are reported as information values. The results produce lower relative deviation if compared with the mean reported concentration values submitted by the laboratories participating in the proficiency test. The analysis involves full peak efficiency calibration of the HPGe detector for all counting geometries and characterization of neutron flux at the irradiation channel by determining thermal to epithermal flux ratio and epithermal flux shape factor using Au and Zr flux monitors. The u-score is less than 1 for majority of the elements.

Precision measurement of the n-3He incoherent scattering length using neutron interferometry

We report the first measurement of the low-energy neutron-(3)He incoherent scattering length using neutron interferometry: b_{i};{'} = (-2.512 +/- 0.012 stat +/- 0.014 syst) fm. This is in good agreement with a recent calculation using the AV18 + 3N potential. The neutron-(3)He scattering lengths are important for testing and developing nuclear potential models that include three-nucleon forces, effective field theories for few-body nuclear systems, and neutron scattering measurements of quantum excitations in liquid helium. This work demonstrates the first use of a polarized nuclear target in a neutron interferometer.

Association of Obesity and Breast Cancer Risk: The Role of Estrogen, Tumor Necrosis Factor-alpha, and Adiponectin as Risk factors (preliminary study)

BACKGROUND: Breast cancer is the most frequent cancer diagnosed among women. Many factors influence the carcinogenesis of breast cancer. The aim of this study to analyze the role of obesity (waist circumference and body mass index), serum Estradiol levels, TNF-α, and Adiponectin in the occurrence of breast cancer.METHODS: This was observational study with casecontrol design. Eleven breast cancer patients as cases and twelve Fibroadenoma Mammae (FAM) patients as controls were analyzed. The serum Estrogen, TNF-α and Adiponectin were examined in their association with breast cancer risk.RESULTS: Women with breast tumor and waist circumference > 80 cm have significantly higher breast cancer risk than women with breast tumor and waist circumference <80 cm (OR 8.75; 95% CI=1.24-61.88; p=0.029). Women with breast tumor and higher serum TNF-α levels (>2.30 pg/ml) have higher breast cancer risk (19.25 times) than women with breast tumor and have lower serum TNF-α levels (95% CI=1.77-209.55, p=0.015). Whereas, women with breast tumor and lower Adiponectin/TNF-α ratio (< 2.13) have higher breast cancer risk (22.5 times) than women with breast tumor and higher Adiponectin/TNF-α (95% CI=2.60-194.51; p=0.005).CONCLUSION: These results suggest that high concentration of serum TNF-α, waist circumference >80 cm and low Adiponectin/TNF-α ratio in women with breast tumor are significantly associated with an increased risk for breast cancer.KEYWORDS: Obesity, breast cancer, adiponectin/TNF-α ratio

Mechanism of p300 specific histone acetyltransferase inhibition by small molecules

Dysfunction of histone acetyltransferases (HATs) leads to several diseases including cancer, diabetes, and asthma. Therefore, small molecule inhibitors and activators of HATs are being considered as new generation therapeutics. Here, we report the molecular mechanisms of p300 HAT inhibition by specific and nonspecific HAT inhibitors: garcinol, isogarcinol, and 1 (LTK14). The p300 specific HAT inhibitor 1 behaves as a noncompetitive inhibitor for both acetyl-CoA and histone, unlike nonspecific HAT inhibitors garcinol and isogarcinol. The isothermal calorimetric data suggest that there is a high affinity enthalpy driven single binding site for 1 on p300HAT domain in contrast to two binding sites for garcinol and isogarcinol. Furthermore, the precise nature of molecular interactions was determined by using fluorescence, docking, and mutational studies. On the basis of these observations, we have proposed the mechanisms of specific versus nonspecific HAT inhibition by these small molecule compounds, which may be useful to design therapeutically favorable HAT inhibitors.