Harmonic mode-locked noise-like pulses under a Q-switched envelope in an erbium doped all-fiber ring laser.

We report for the first time, to the best of our knowledge, harmonic mode-locked noise-like pulses under a Q-switched envelope in an all-fiber erbium doped ring laser cavity, mode locked using the nonlinear polarization rotation (NPR) technique. For a cavity with a fundamental repetition rate of 1.33 MHz, stable mode-locked noise-like pulses, with few nanoseconds durations, single pulse energies around 30-40 nJ, and Q-switched repetition rates up to 31 kHz, were produced and characterized from the fundamental to the eighth harmonic. The formation and evolution of Q-switched harmonic mode-locked noise-like pulses were preceded by the formation of Q-switched mode-locked noise-like pulse bunches. This is also the first report on noise-like bunches under a Q-switched envelope, to our knowledge. Our studies also provide further insights into the interplay of different physical mechanisms involved in the production of such ultrashort pulses. Such sources should prove especially useful for efficient supercontinuum generation and laser micromachining.

Defaecation disorders among information technology personnel: A cross-sectional study.

Background Individuals working in the information technology (IT) industry are likely to develop lifestyle disorders. We aimed to determine the presence of defaecation-related disorders in IT personnel in Chennai. Methods This cross-sectional, questionnaire-based study was done from June to December 2018. We included employees between 18 and 60 years of age and excluded those with <1 year stay in Chennai, pregnancy and those who sent incomplete responses. The cohort was classified as normal, irritable bowel syndrome (IBS), faecal evacuation disorder (FED) and a combination of the latter two. Results The overall response rate was 95.6%. The study included 54.7% of men, and the median age was 31 years. The majority of respondents used an Indian toilet (554; 58%). Almost all (96.2%) passed stools daily, and stool consistency was soft in 59%. Based on the study criteria, 180 (18.8%) had FED, 56 (5.9%) had IBS and a small group had a combination of symptoms of IBS and FED (20; 2.1%). Respondents with symptoms of IBS had a higher proportion of comorbid states (p<0.0001), lesser stool frequency (p<0.0001) and required more toilet time (p<0.00001). Conclusion Over one-fourth (26.7%) of the respondents had defaecation-related issues, 18.8% had symptoms suggestive of FED and 5.6% that of IBS, often above 30 years of age.

Active loss compensation in the resonant optical gyroscope with a "reflector": towards a cost-effective alternative for the navigational grade.

The performance of passive fiber optic gyroscopes involving ring resonators is limited mainly by the loss and finesse of the cavity. In this work, we show performance enhancement of the recently studied resonant fiber optic gyroscope with a "reflector" using active loss compensation. Our gyroscope does not require expensive ultra-narrow linewidth lasers, expensive lock-in detection methods, or polarization-maintaining fibers, which are mandatory for all standard resonant fiber optic gyroscopes. The performance of this gyroscope shows four-fold enhancement in the $Q$Q factor $ (2.2 \times {10^8}) $(2.2×108), compared to an earlier experimental setup involving losses. Enhanced sensitivity to rotation is experimentally demonstrated using loss compensation as well as tuning the embedded reflector in the resonator. A shot-noise-limited sensitivity of 0.03 deg/h is possible with this experimental realization. This work demonstrates that our gyroscope can provide a cost-effective alternative, even in the navigational grade.

Self-beating resonant optical gyroscope with a "reflector": the possibility of high sensitivities at reduced costs.

Using simulations and theoretical analysis, we present an innovative readout technique that uses the change in a beat frequency signal for sensing rotation in the resonant fiber gyroscope with a "reflector." Unlike traditional fiber optic gyros, this gyroscope uses an embedded reflecting element that deliberately couples the clockwise and counter-clockwise propagating waves for sensing rotation. Our analytical results predict increased immunity to the degrading effects of backscattering, Kerr nonlinearities, and ambient variations at an optimum nonreciprocal bias. Using just a few meters of fiber and without requiring a very narrow-linewidth source, sensitivities below 1 deg/h along with a dynamic range greater than 106 deg/h are predicted. The technique has the potential to provide a cost-effective solution in the tactical grade.

Combination of noise removal and contrast enhancement methods for the preprocessing of mammogram images - towards the detection of breast cancer / Combinação de métodos de remoção de ruído e aperfeiçoamento de contraste para o pré-processamento de imagens de mamografias - rumo à detecção do câncer de mama

Breast cancer is a major killer disease for women and men. It can be treated and controlled only if it is detected at its earlier stage. Early detection can be achieved by the help of Computer Aided Detection (CAD) methods. From the detailed study on previous researches, it is found that, there is no system producing 100% accuracy because of one or more reasons. Absence of effective preprocessing is the discussed reason that obstructs the detection accuracy of CAD method. Noise removal and contrast enhancement are the two types of preprocessing. There is no system performs both the preprocessing on mammogram image. This work is an attempt to develop an enhanced preprocessing method for CAD of breast cancer by incorporating suitable noise reduction and contrast enhancement methods in the conventional CAD system. Among the available noise reduction techniques, Fast Discrete Curvelet Transform (FDCT) based UnequiSpaced Fast Fourier Transform (USFFT) has been utilized and the Modified Local Range Modification (MLRM) technique has been utilized for contrast enhancement. Contrast enhancement after noise reduction double enhances the mammogram image and the proposed methods MSE value for the mammogram image mdb072 has been 1.44% reduced when comparing to the LRM method. Reduction in MSE increases the PSNR to 0.16%. Many mammogram images have been tested and the result shows that, increase in contrast, decrease in mean square error and increase in peak signal to noise ratio when comparing to existing methods.

Introdução: O câncer de mama é uma grande doença mortal para mulheres e homens. Ele só pode ser tratado e controlado se for detectado em sua fase inicial. A detecção precoce pode ser alcançada com a ajuda de métodos de detecção assistida por computador (CAD). A partir do estudo detalhado sobre pesquisas anteriores, verifica-se que, não há um sistema com 100% de precisão por causa de uma ou mais razões. A ausência de pré-processamento efetivo é o motivo discutido que obstrui a precisão de detecção do método CAD. A remoção de ruído e o aprimoramento do contraste são os dois tipos de pré-processamento. Não existe um sistema que realize ambos os pré-processamentos na imagem da mamografia. Objetivo: Este trabalho é uma tentativa de desenvolver um método de pré-processamento aprimorado para CAD de câncer de mama, incorporando métodos adequados de redução de ruído e aprimoramento de contraste no sistema de CAD convencional. Métodos: Entre as técnicas de redução de ruído disponíveis, a transformada de curva discreta rápida (FDCT) baseada na transformada rápida de Fourier desigualmente espaçada (USFFT) foi utilizada e a técnica de modificação de faixa local modificada (MLRM) foi utilizada para aprimoramento de contraste. Resultados: o aprimoramento do contraste após a redução do ruído melhora o dobro da imagem da mamografia e os métodos propostos para o valor de MSE para a imagem da mamografia mdb072 foram reduzidas em 1,44% quando comparados ao método LRM. A redução de MSE aumenta o PSNR para 0,16%. Conclusão: muitas imagens de mamografia foram testadas e o resultado mostra que, aumento no contraste, diminuição do erro quadrático médio e aumento da relação pico do sinal/ruído quando comparado aos métodos existentes.

Precision electron-gamma spectroscopic measurements in the decay of 177Lu.

Complete precision electron and gamma spectroscopy measurements were undertaken for the 6.647 day decay of (177)Lu. Precision measurements of the K, L, and M internal conversion coefficients (ICCs) were made using a high transmission Mini Orange Electron Spectrometer coupled to a Si(Li) detector. We also report energies and intensities of the 6 gamma rays measured with a large volume 60 cc HPGe detector and 9 X-rays with better precision. The energies and intensities of the beta transitions from (177)Lu leading to the levels in the daughter (177)Hf were calculated by transition intensity balance at the levels.

Efficacy and tolerability of cefditoren pivoxil in uncomplicated skin and skin structure infections in Indian patients.

BACKGROUND: Uncomplicated skin and skin structure infections (uSSSI) are commonly encountered community-acquired infections and are typically confined to the superficial layers of the skin. Hence, they seldom lead to the destruction of skin structures. AIMS: To evaluate the efficacy and tolerability of cefditoren pivoxil in uSSSI in Indian patients. METHODS: One hundred and seventy-eight patients diagnosed with uncomplicated SSSI were enrolled in this randomized, comparative, multicentric study. Patients received either cefditoren pivoxil or cefdinir for ten days. Efficacy was assessed both clinically and microbiologically. Safety evaluation consisted of reporting of type, frequency, severity, and causal relationship of adverse events. RESULTS: One hundred and fifty-one patients completed the study. Clinical and bacteriological efficacy of cefditoren pivoxil was comparable to that of cefdinir in the treatment of uSSSI. One hundred and five patients were eligible for per protocol (PP) analysis of bacteriological outcome and clinical efficacy. Clinical cure or improvement was achieved in 98.00% patients treated with cefditoren pivoxil and 98.18% patients treated with cefdinir. In the modified Intent to Treat (mITT) patient population, clinical cure or improvement was recorded in 97.33% patients treated with cefditoren pivoxil and 96.20% patients treated with cefdinir. Microbiological eradication (or presumed eradication) was recorded in 88.00% patients treated with cefditoren pivoxil and 94.55% patients treated with cefdinir. The above differences in the outcome rates between the two drugs were not statistically significant. Six adverse events (AEs) (two in cefditoren group and four in cefdinir group) were reported in this study. CONCLUSION: Cefditoren pivoxil 200 mg b.i.d. was effective and well tolerated in the treatment of uSSSI.

Electron-gamma spectroscopic measurements in 131 Cs.

The decay of 131 Ba to levels of 131 Cs has been studied using an HPGe detector for gamma-ray and a mini-orange electron spectrometer for conversion electron measurements. Our experiment identifies 76 gamma transitions in this decay, including 15 new gamma rays and 6 new K-conversion electron lines. The results also include M2 multipolarity assignment for the 269 keV transition, E2 assignment to two newly observed transitions, M1 + E2 for the 406 and 417 keV transitions and M3 for the 533.67 keV transition. A revised 131 Cs level scheme is proposed. While confirming the existence of 15 well-established levels, we present strong evidence from our beta decay study for five levels at 496, 764, 775, 1044 and 1258 keV which were earlier observed in reaction studies. Spin-parity assignments to a few other levels are also suggested. The level structure of 131 Cs is discussed in the light of the intermediate coupling model.

All-optical spatial filtering with power limiting materials.

We demonstrated that a power limiting mechanism could potentially be used for self-adaptive, all-optical Fourier image processing. Reverse saturable absorbers like porphyrins are chosen due to their fluence dependent power limiting property, which triggers at relatively low intensities. At low input intensities, below the power-limiting threshold, the 4-f configuration will image the object onto the CCD camera without any spatial frequency filtering. As the input intensity is increased above the threshold level, dc and low spatial frequencies are blocked resulting in edge-enhanced images containing high spatial frequencies. The incident intensity sets the higher limit on the band of frequencies blocked. In addition, the use of the same experimental setup for both power limiting experiments and optical image processing demonstrates that in the case of any bright image bearing laser beam, the sensitive detectors are protected, by blocking the intense low spatial frequencies.

In-vitro screening of cissus quadrangularis L. Variant ii against helicobacter pylori.

Cissus quadrangularis L. variant II belonging to the family Vitaceae was screened for its activity Hellcobacter pylori (Hp) human isolates. Flowering and vegetative period samples were analyzed. Aqueous (hot and cold) and solvent extracts (acetone, chloroform and methanol) were screened. Among them chloroform was observed to recover bioactive principles with low MIC and MLC. MIC and MLC was 40 µg/ml for flowering period. Whereas for vegetative period MIC was 40 µg/ml and MLC was 40 µg/ml respectively. Extracts from samples collected during flowering period were better than that of vegetative period. The results confirm the traditional use of the plant in PUD.

Sparfloxacin in the treatment of purulent sinusitis-a multicentric study in Indian patients.

Sparfloxacin, a new quinolone antibacterial was used to treat one hundred and thirty two patients with acute purulent sinusitis, at a dosage of 400 mg on the first day followed by 200 mg once daily for a further four days. A clinically successful outcome (defined as disappearance of nasal discharge, fever, pain, tenderness over the sinuses and headache) was recorded in 122 ( 95.3%) patients. Sparfloxacin was well tolerated. Fourteen adverse experiences were reported in 7 patients ( 5.3%); they were mainly gastrointestinal and mild. No phototoxic or cardiological adverse events occurred. An unusual feature was that Staphylococcus aureus and Pseudomonas spp. were the most common bacterial species isolated from middle meatal was of patients in this study.

Risperidone in Indian patients with schizophrenia.

Conventional antipsychotic agents are not effective against negative symptoms of schizophrenia and are also noted for their extrapyramidal side effects. Risperidone is a noval antipsychotic agent whose dual antagonism of dopamine and serotonin receptors is believed to underlie its efficacy against negative symptoms and the low incidence of extrapyramidal side effects. An open, non-comparative study of seven weeks duration was performed to evaluate risperidone in the treatment of schizophrenia in Indian patients. Previous antipsychotic therapy was discontinued for a week before risperidone therapy was initiated. At the end of six weeks of risperidone therapy, clinical improvement (≥ 20% reduction in total score on positive and negative syndrome scale for schizophrenia (PANSS;; was shown by 128 (87.7%) of the 146 evaluable patients. Statistically significant reduction (p < 0.05) occurred in the total score of this scale and in the subscale scores for positive, negative and general psychopathology symptoms and in the clinical global impression severity score. The number of patients with adverse experiences were 108 (65.5%) at baseline and 120 (72.7%) at the end of risperidone therapy. Extrapyramidal symptoms, seen in 65 (39.4%) patients compared to 22 (13.3%) patients at baseline, were largely mild to moderate in intensity.

Higher AUCs on oral administration of omeprazole and felodipine in Indian volunteers--are they clinically important?

Bioavailability studies with single oral doses of omeprazole 20 mg (enteric coated formulation) and felodipine 10 mg (extended release formulation) were performed in Indian volunteers to confirm that adequate plasma concentrations are obtained in Indian subjects. Plasma samples were analysed by chromatographic methods. The AUCs of omeprazole were about 3 fold higher and those of felodipine 2 fold higher than AUCs reported in Western subjects. This has no toxicological implications with respect to omeprazole, but whether lower dose of omeprazole may be sufficient in Indian patients with acid related diseases would require acid inhibition studies. In the case of felodipine the higher AUCs in Indian subjects suggest a need for a lower strength formulation (2.5 mg) to fine-titrate the dosage to obtain optimal antihypertensive effects with minimal adverse effects.

Nitroimidazoles, Part XXIII--activity of satranidazole series against anaerobic infections.

A large number of nitroimidazoles have been examined for in vitro activity against three anaerobes - Bacteroides fragilis (Bf), a strain of Bf resistant to metronidazole (16a) and Clostridium perfringens and many found to be active. Among these may be mentioned 1-methyl-5-nitroimidazoles carrying N - bound hetetocycles at position 2, such as satranidazole 1a, 1b, 1c, 1k, 1n and 1v which are at least twice as active as metronidazole (16a), ornidazole (16b) and tinidazole (16c). Even more active are 5-nitroimidazolyl benzimidazole 5d, -thiazolidinone 6b and thiadiazolidine dioxide 8a. Many other types of compounds derived from 1-methyl-2-amino-5-nitroimidazole are feebly active. Among 5-nitroimidazoles with a carbon substituent at position 2, 16a, 16b and 16c are equiactive while dimetridazole 14f is more active than 16a against Bf. Some 2-vinyl derivatives are very potent, with 18f and 18i being outstanding. Activity better than that of metronidazole is seen for nitroimidazooxazepines, e.g. 29d. 5-Nitroimidazoles are more active against anaerobes than 4-nitro isomers. Antianaerobic and antiamoebic activities generally run parallel in these classes of compounds. The study has led to the elaboration of the antianaerobic profile of satranidazole 1a.

Satranidazole: experimental evaluation of activity against anaerobic bacteria in vitro and in animal models of anaerobic infection.

Satranidazole, a 5-nitroimidazole derivative, was tested for its activity against reference strains and clinical isolates of anaerobic bacteria in vitro and in two murine models of anaerobic infection in comparison with metronidazole, tinidazole, ornidazole and clindamycin. The MIC90 of satranidazole against 50 clinical isolates of anaerobes was 0.25 mg/l which was four-fold lower than the MIC90 of metronidazole, tinidazole and ornidazole (MIC90 = 1.0 mg/l). In a fatal murine infection with Fusobacterium necrophorum, ATCC 27852, the ED50 of satranidazole was 2.1 +/- 0.62 mg/kg while for metronidazole, ornidazole, tinidazole and clindamycin, the values were 11.31 +/- 1.99, 8.70 +/- 2.21, 13.19 +/- 2.39 and 7.10 +/- 1.73 respectively. In a subcutaneous Bacteroides fragilis abscess in mice, satranidazole alone produced a three log reduction in cfu of the infecting organism at 10 mg/kg, the lowest dose tested. At 100 mg/kg, only satranidazole and clindamycin effected a complete sterilization of abscesses.

Leucocyte migration inhibition with human heart valve glycoproteins and group A streptococcal ribonucleic acid proteins in rheumatic heart disease and post-streptococcal glomerulonephritis.

Leucocyte migration inhibition (LMI) tests have been performed with leucocytes obtained from patients with acute rheumatic carditis, established rheumatic valvular disease with and without rheumatic reactivation, post-streptococcal glomerulonephritis and healthy volunteers, using human heart valve glycoprotein (HVGP) antigens and ribonucleic acid protein antigens (P-RNA) from Group A streptococci, types 5, 6 and 12 and a Group C streptococcus. Significantly increased LMI was observed with HVGP and P-RNA antigens of Group A streptococci in patients with clinical evidence of rheumatic valvular damage. Healthy volunteers and patients with poststreptococcal glomerulonephritis did not show any increase in LMI to these antigens. This suggests that cell-mediated immune mechanisms may be involved in the production of tissue lesions in rheumatic fever.