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Narrow linewidth visible light lasers are critical for atomic, molecular and optical (AMO) applications including atomic clocks, quantum computing, atomic and molecular spectroscopy, and sensing. Historically, such lasers are implemented at the tabletop scale, using semiconductor lasers stabilized to large optical reference cavities. Photonic integration of high spectral-purity visible light sources will enable experiments to increase in complexity and scale. Stimulated Brillouin scattering (SBS) is a promising approach to realize highly coherent on-chip visible light laser emission. While progress has been made on integrated SBS lasers at telecommunications wavelengths, barriers have existed to translate this performance to the visible, namely the realization of Brillouin-active waveguides in ultra-low optical loss photonics. We have overcome this barrier, demonstrating the first visible light photonic integrated SBS laser, which operates at 674 nm to address the 88Sr+ optical clock transition. To guide the laser design, we use a combination of multi-physics simulation and Brillouin spectroscopy in a 2 meter spiral waveguide to identify the 25.110 GHz first order Stokes frequency shift and 290 MHz gain bandwidth. The laser is implemented in an 8.9 mm radius silicon nitride all-waveguide resonator with 1.09 dB per meter loss and Q of 55.4 Million. Lasing is demonstrated, with an on-chip 14.7 mW threshold, a 45% slope efficiency, and linewidth narrowing as the pump is increased from below threshold to 269 Hz. To illustrate the wavelength flexibility of this design, we also demonstrate lasing at 698 nm, the wavelength for the optical clock transition in neutral strontium. This demonstration of a waveguide-based, photonic integrated SBS laser that operates in the visible, and the reduced size and sensitivity to environmental disturbances, shows promise for diverse AMO applications., 23 pages, 10 figures

High quality-factor (Q) optical resonators are a key component for ultra-narrow linewidth lasers, frequency stabilization, precision spectroscopy and quantum applications. Integration in a photonic waveguide platform is key to reducing cost, size, power and sensitivity to environmental disturbances. However, to date, the Q of all-waveguide resonators has been relegated to below 260 Million. Here, we report a Si3N4 resonator with 422 Million intrinsic and 3.4 Billion absorption-limited Qs. The resonator has 453 kHz intrinsic, 906 kHz loaded, and 57 kHz absorption-limited linewidths and the corresponding 0.060 dB m−1 loss is the lowest reported to date for waveguides with deposited oxide upper cladding. These results are achieved through a careful reduction of scattering and absorption losses that we simulate, quantify and correlate to measurements. This advancement in waveguide resonator technology paves the way to all-waveguide Billion Q cavities for applications including nonlinear optics, atomic clocks, quantum photonics and high-capacity fiber communications., Integrated photonic all-waveguide resonators are a critical component in many future applications. Here the authors develop an optimized photonic all-waveguide resonator with an ultra-high quality factor, Q, of almost half a billion, and a narrow sub-MHz linewidth.

We demonstrate 0.034 dB/m loss waveguides in a 200-mm wafer-scale, silicon nitride (Si3N4) CMOS-foundry-compatible integration platform. We fabricate resonators that measure up to a 720 million intrinsic Q resonator at 1615 nm wavelength with a 258 kHz intrinsic linewidth. This resonator is used to realize a Brillouin laser with an energy-efficient 380 µW threshold power. The performance is achieved by reducing scattering losses through a combination of single-mode TM waveguide design and an etched blanket-layer low-pressure chemical vapor deposition (LPCVD) 80 nm Si3N4 waveguide core combined with thermal oxide lower and tetraethoxysilane plasma-enhanced chemical vapor deposition (TEOS–PECVD) upper oxide cladding. This level of performance will enable photon preservation and energy-efficient generation of the spectrally pure light needed for photonic integration of a wide range of future precision scientific applications, including quantum, precision metrology, and optical atomic clocks.

Atomic, molecular and optical (AMO) visible light systems are the heart of precision applications including quantum, atomic clocks and precision metrology. As these systems scale in terms of number of lasers, wavelengths, and optical components, their reliability, space occupied, and power consumption will push the limits of using traditional laboratory-scale lasers and optics. Visible light photonic integration is critical to advancing AMO based sciences and applications, yet key performance aspects remain to be addressed, most notably waveguide losses and laser phase noise and stability. Additionally, a visible light integrated solution needs to be wafer-scale CMOS compatible and capable of supporting a wide array of photonic components. While the regime of ultra-low loss has been achieved at telecommunication wavelengths, progress at visible wavelengths has been limited. Here, we report the lowest waveguide losses and highest resonator Qs to date in the visible range, to the best of our knowledge. We report waveguide losses at wavelengths associated with strontium transitions in the 461 nm to 802 nm wavelength range, of 0.01 dB/cm to 0.09 dB/cm and associated intrinsic resonator Q of 60 Million to 9.5 Million, a decrease in loss by factors of 6x to 2x and increase in Q by factors of 10x to 1.5x over this visible wavelength range. Additionally, we measure an absorption limited loss and Q of 0.17 dB/m and 340 million at 674 nm. This level of performance is achieved in a wafer-scale foundry compatible Si3N4 platform with a 20 nm thick core and TEOS-PECVD deposited upper cladding oxide, and enables waveguides for different wavelengths to be fabricated on the same wafer with mask-only changes per wavelength. These results represent a significant step forward in waveguide platforms that operate in the visible, opening up a wide range of integrated applications that utilize atoms, ions and molecules including sensing, navigation, metrology and clocks.

We demonstrate an integrated photonics infrastructure for atomic laser cooling. We trap 5 x 106 87Rb atoms in a magneto-optical trap using free-space cooling beams emitted from a SiN photonic integrated circuit.

We report an integrated Si3N4 3m length waveguide coil resonator for operation at 674nm. Stabilization of a laser to this cavity is demonstrated, resulting in 4 orders of magnitude FN reduction, an ILW 4.2kHz and ADEV 3.5x10-12.

Spectrally pure lasers, the heart of precision high-end scientific and commercial applications, are poised to make the leap from the laboratory to integrated circuits. Translating this performance to integrated photonics will dramatically reduce cost and footprint for applications such as ultrahigh capacity fibre and data centre networks, atomic clocks and sensing. Despite the numerous applications, integrated lasers currently suffer from large linewidth. Brillouin lasers, with their unique properties, offer an intriguing solution, yet bringing their performance to integrated platforms has remained elusive. Here, we demonstrate a sub-hertz (~0.7 Hz) fundamental linewidth Brillouin laser in an integrated Si3N4 waveguide platform that translates advantages of non-integrated designs to the chip scale. This silicon-foundry-compatible design supports low loss from 405 to 2,350 nm and can be integrated with other components. Single- and multiple-frequency output operation provides a versatile low phase-noise solution. We highlight this by demonstrating an optical gyroscope and a low-phase-noise photonic oscillator. Brillouin lasing with 0.7 Hz fundamental linewidth is observed by optically exciting a monolithic bus–ring Si3N4 waveguide resonator. The Brillouin laser is applied to an optical gyroscope and a low phase-noise photonic microwave oscillator.

We report a 1.35 mW threshold Brillouin laser with measured 0.47 Hz fundamental and 525 Hz integral linewidths using a 422 Million intrinsic Q Si3N4 resonator.

We report laser stabilization with record low frequency noise of 0.08 Hz2/Hz at 70 kHz offset and a 150 Hz integral linewidth using an integrated 4-meter waveguide coil resonator with 144 Million intrinsic Q.

High Q optical resonators that are a key component for ultra-narrow linewidth lasers, frequency stabilization, precision spectroscopy and quantum applications. Integration of these resonators in a photonic waveguide wafer-scale platform is key to reducing their cost, size and power as well as sensitivity to environmental disturbances. However, to date, the intrinsic Q of integrated all-waveguide resonators has been relegated to below 150 Million for a non-etched waveguide resonator and 230 Million for a waveguide-coupled etched silica microresonator. Here, we report an all-waveguide Si3N4 resonator with an intrinsic Q of 422 Million and a 3.4 Billion absorption loss limited Q. The resonator linewidth measures at 453 kHz intrinsic linewidth, 906 kHz loaded linewidth with finesse of 3005. The corresponding linear loss of 0.060 dB/m is the lowest reported to date for an all-waveguide design with deposited upper cladding oxide. These are the highest intrinsic and absorption loss limited Q factors and lowest linewidth reported to date for a photonic integrated all-waveguide resonator. This level of performance is achieved through a careful reduction of scattering and absorption loss components and redeposition of a thin nitride layer. We quantify, simulate and measure the various loss contributions including scattering and absorption and describe a surface-state dangling bond absorption that we believe is passivated by the redeposited layer. In addition to the ultra-high Q and narrow linewidth, the resonator has a large optical mode area and volume, both critical for ultra-low laser linewidths and ultra-stable, ultra-low frequency noise reference cavities. These results demonstrate the performance of bulk optic and etched resonators can be realized in a photonic integrated solution, paving the way towards photonic integration compatible Billion Q cavities for precision scientific systems and applications such as nonlinear optics, atomic clocks, quantum photonics and high-capacity fiber communications systems on-chip.

D-shape SÌ3N4 waveguides are fabricated by dielectric lift-off process. We measure ultra-low loss for a 90nm-thick core of 2.42 dB/m at 1550 nm and a loaded Q-factor of 1.12x106 for a 0.8 mm radius resonator.

We report tightly confining Si3N4 waveguides with record low loss at key strontium clock visible wavelengths, 0.03dB/cm at X=698nm, 0.08dB/cm at 450nm and ring resonators with measured loaded Q of 8.6 million at X=674nm.

We report the first direct evidence of visible wavelength spontaneous Brillouin scattering in a photonic integrated waveguide. A Si3N4 spiral is pumped at 674nm and produces a 25.11GHz shifted, 400MHz-wide, Stokes signal, as predicted by simulations.

Today air pollution is responsible for many health problems in the urban areas. Many metros cities in the world are suffering from air pollution problems. Due to air pollution problem, not only humans but animals and birds were also suffering from this problem. This paper provides an idea that how we can reduce pollution from the air. The simple way to reduce pollution from the air is to grow more and more plants. But in metro cities, there was not that much place available to grow plants or trees on the land. Therefore we are going to introduce “Vertical Forest by Hydroponic Method”. We can grow plants on building balcony by Hydroponic technique. In this, we can grow the plant without the help of soil. If we grow the plant by Aquaponics technique than due to that there will be less load on building the structure as compared to using soil.

Background: Cervical cancer is one of the most common cancers of Indian females. Western Rajasthan differs a lot from rest of India in respect of geographical conditions, environment, culture, population density etc. and it also has relatively lower literacy rate which is one of the risk factor for many diseases. The objective of this study was to estimate the prevalence of cervical cytological pattern in females of western Rajasthan by using conventional Papanicolaou (Pap) smears for the screening of inflammatory, premalignant and malignant lesions of the cervix. Methods: This cross sectional study was conducted at tertiary care institute of western Rajasthan for 1.5 year duration, on 1768 females who were screened by Pap smear examination. After staining with conventional Papanicolaou technique, all smears were classified as per Bethesda nomenclature. Results: Out of 1768 smears 1039 (58.7%) were abnormal Pap smears, 445 (25.1%) were normal Pap smears while 284 (16.1%) smears had inadequate sample material to be examined. Out of 1039 abnormal smears, 956 (92.01%) smears reported to have inflammatory/reactive changes whereas 26 (2.50%) had atrophic changes in Pap smear and abnormality in epithelial cell was reported in 57(5.49%) smears. Conclusions: Pap smear examination is an effective screening procedure to detect cervical cytological abnormalities. Routine cytological screening by Pap smear should be offered to all women above 19 years or within 3 years of sexual activity. It is recommended to improve the awareness about the disease amongst females and skills of health care personal about proper preparation of Pap smear.

Optical resonator-based frequency stabilization plays a critical role in ultra-low linewidth laser emission and precision sensing, atom clocks, and quantum applications. However, there has been limited success in translating traditional bench-top stabilization cavities to compact on-chip integrated waveguide structures that are compatible with photonic integration. The challenge lies in realizing waveguides that not only deliver low optical loss but also exhibit a low thermo-optic coefficient and frequency noise stability. Given the problematic sources of frequency noise within dielectrics, such as thermorefractive noise, resonators with small thermo-optic response are desirable for on-chip reference cavities. We report the first demonstration of a Ta2O5 (tantala) waveguide core fabricated on a crystal quartz substrate lower cladding with TEOS-PECVD SiO2 upper cladding. This waveguide offers significant advantages over other waveguides in terms of its low thermo-optic coefficient and reduced thermorefractive-related frequency noise. We describe the waveguide structure and key design parameters as well as fabrication considerations for processing tantala on quartz waveguides. We report a waveguide thermo-optic coefficient of −1.14 × 10−6 RIU/K, a value that is over 6 times smaller in magnitude than that of SiO2-substrate tantala waveguides, with a propagation loss of 1.19 dB/cm at 1550 nm and

Background: Anemia in pregnancy is related to maternal-fetal morbidity and mortality. In developing countries like India it is important to study prevalence and pattern of anemia in pregnancy especially in the region with higher maternal mortality rate like western Rajasthan. The main objective was to study the prevalence and pattern of anemia in second and third trimester pregnant females in western Rajasthan. Methods: In this cross sectional study females with second and third trimester pregnancy were evaluated for presence of anemia with its morphological type and severity. Results: 17,552 second and third trimester pregnant females were evaluated and prevalence of anemia was found 48.4%. The percentages of mild, moderate and severe anemia were 35.1%, 51.3% and 13.4% respectively. Most common morphological type was microcytic hypochromic anemia (51%) followed by normocytic normochromic anemia (32%), dimorphic anemia (13%) and macrocytic anemia (4%). Conclusions: There is high prevalence of anemia in pregnant females. This warrants the need of proper prophylaxis and early diagnosis of anemia in pregnancy to minimize the maternal-fetal morbidity and mortality.

Background: Body image perception is being shaped by unrealistic ideals portrayed in the media. Body dissatisfaction is one of the most consistent and robust risk factors for eating disorders, low self-esteem, depression, and obesity. Therefore, the objective of the current study is to ascertain the body image perception, abnormal eating attitudes and the role of media among undergraduate students of a medical college in Delhi, India.Methods: Cross-sectional study on 370 undergraduate medical students of Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India selected using stratified random sampling. India. Students completed a self-administered questionnaire which consist of demographic information, perceived body image, Eating Attitudes test (EAT-26) to assess eating attitudes, Socio Cultural Attitude Towards Appearance Questionnaire 3(SATAQ-3) scale for the role of media on body image perception. Data was analyzed using SPSS v21.Results: A total of 370 students (57.6% males and 42.4% females) aged 17-30 years, mean age of 20.30 years±2.02(SD). Abnormal body image perception was seen in 35.4%, 21.1% had abnormal eating attitude (EAT-26≥20), 36.5%, 40.5% agreed to be influenced by models and athletic figures in media respectively, 42.2% accepted that media was their source of information regarding standards of attractiveness, 27.6% felt pressured to be attractive according to SATAQ-3. Males more than females had disordered eating attitudes and felt media pressure to achieve an ideal body image. Significant association was observed between age and perceived body image (p=0.033), gender and EAT-26 score (p=0.039), EAT 26 and perceived body image (p=0.006), general internalization of media and perceived body image (p=0.003), internalization-general, internalization-athlete, media as source of information and EAT-26 score (

Existing fingerprint classification techniques make use of Level-1 or Level-2 features or their combination for fingerprint classification. On the other hand, Level-3 features have not been explored much for fingerprint classification. Specifically, the use of crease for fingerprint classification does not exist in the literature. In this work, we explore the use of crease features for fingerprint classification. Experiments are performed on the publicly available Hong Kong PolyU high-resolution fingerprint database DBII. Our experimental results are very encouraging and indicate that creases have huge potential to improve the performance of fingerprint classification.

The advancements made in tissue culture techniques has made it possible to regenerate various horticultural species in vitro as micropropagation protocols for commercial scale multiplication are available for a wide range of crops. Clonal propagation and preservation of elite genotypes, selected for their superior characteristics, require high degree of genetic uniformity amongst the regenerated plants. However, plant tissue culture may generate genetic variability, i.e., somaclonal variations as a result of gene mutation or changes in epigenetic marks. The occurrence of subtle somaclonal variation is a drawback for both in vitro cloning as well as germplasm preservation. Therefore, it is of immense significance to assure the genetic uniformity of in vitro raised plants at an early stage. Several strategies have been followed to ascertain the genetic fidelity of the in vitro raised progenies comprising morpho-physiological, biochemical, cytological and DNA-based molecular markers approaches. Somaclonal variation can pose a serious problem in any micropropagation program, where it is highly desirable to produce true-to-type plant material. On the other hand, somaclonal variation has provided a new and alternative tool to the breeders for obtaining genetic variability relatively rapidly and without sophisticated technology in horticultural crops, which are either difficult to breed or have narrow genetic base. In the present paper, sources of variations induced during tissue culture cycle and strategies to ascertain and confirm genetic fidelity in a variety of in vitro raised plantlets and potential application of variants in horticultural crop improvement are reviewed.

We propose a regression test selection technique that is based on analysis of source code of an object-oriented program. First we construct a System dependency graph model of the original program from the source code. When some modification is executed in a program, the constructed model is updated to reflect the changes. Our approach in addition to capturing control and data dependencies represents the dependencies arising from object-relations. The test cases that exercise the affected model elements in the program model are selected for regression testing. In our approach System Design Graph representation will be used for regression test selection for analyzing and comparing the code changes of original and modified program. Empirical studies carried out by us show that our technique selects on an average of 26.36. % more fault-revealing test cases compared to a Control Dependence Graph based technique while incurring about 37.34% increase in regression test suite size.

Ber (Ziziphus mauritiana Lamk.) demonstrates a rich biodiversity with respect to morphometeric and fruit characters. Much of this has been generated on account of natural cross pollination. In depth studies have been conducted in different crops to evaluate the impact of hybridity on plant morphometric and yield parameters but very few studies were undertaken to evaluate the impact on metabolite constitution. Accordingly, the present study was aimed at evaluating the foliar flavonoid spectrum of two hybrids developed at CIAH, Bikaner viz-a-viz their parents. The results demonstrated that some compounds encountered in parents were present in profiles of hybrids also. Similarly, some novel compounds were also found which might have produced as a result of new gene combinations in hybrid. Like wise some compounds present in parents were not found in hybrids. These could be explained on the basis of epistatic phenomenon.

Human skin is a remarkably efficient barrier, designed to keep ‘‘our insides in and the outsides out’’. This barrier property causes difficulties for transdermal delivery of therapeutic agents. One long-standing approach to increase the range of drugs that can be effectively delivered via this route has been to use penetration enhancers, chemicals that interact with skin constituents to promote drug flux. To-date, a vast array of chemicals has been evaluated as penetration enhancers (or absorption promoters), yet their inclusion into topical or transdermal formulations is limited since the underlying mechanisms of action of these agents are seldom clearly defined. In this article we review some uses of the more widely investigated chemical penetration enhancers and discuss possible mechanisms of action.

Applicability, assessment and work-how of Micro-Wave Assisted Gravity Drainage (MWAGD) process in Mehsana (India) heavy oil field along with added advantages over SAGD were presented in the previous part of this paper [1]. Various studies have been done during last 10 years illustrating wider applications of micro-wave heating of heavy oil reservoirs through quantitative and qualitative exercises. But the main problem that arises in micro-wave heating is very low penetration depth of micro-wave radiations which limits the application of this unconventional thermal EOR method on full field scale. The scope of this paper is to eliminate this problem by using horizontal well pair combination which enhances the drainage area within the heating radius of micro-wave radiations.The phenomenon of conversion of Micro-wave energy to heat energy is described and finally, a mathematical model based on energy balance principle is developed. Two parallel and vertically aligned horizontal wells are drilled. The upper well is production well and lower well is micro-wave source well with their length and vertical separation on the order of 500 meters and 15 meters respectively. In the lower well micro-wave sources are installed at various positions along the length with longitudinal spacing on the order of 20 meters. Advantages of heating of oil from the lower well are explained in lucid manner. This type of installation model confirms the coverage of larger reservoir volume in spite of short penetration depth of micro-wave radiations. Along with volumetric and selective heating in this process heat is developed within the formation fluid rather than being brought to it from the outside, and hence the fluid is heated more uniformly throughout the medium. Also, above proposed model can be applied effectively in case of carbonate formations where uneven sweeping occurs along steam assisted gravity drainage (SAGD) well pairs due to vuggs and fractures.

Drug information centre refer to facility specially set aside for, and specializing in the provision of drug information and related issues. The purpose of drug information center is to provide authentic individualized, accurate, relevant and unbiased drug information to the consumers and healthcare professionals regarding medication related inquiries to the nation for health care and drug safety aspects by answering their call regarding the all critical problems on drug information, their uses and their side effects. Apart from that the center also provides in-depth, impartial source of crucial drug information to meet the needs of the practicing physicians, pharmacists and other health care professionals to safeguard the health, financial and legal interests of the patient and to broaden the pharmacist role visible in the society and community. The service should include collecting, reviewing, evaluating, indexing and distributing information on drugs to health workers. Drug and poisons information centers are best established within major teaching hospitals. This allows access to clinical experience, libraries, research facilities and educational activities. Information present in the current paper will not only enlighten the role of drug information center but also focused on the rational use of drug.