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Water is an essential part of human life controlling the very own existence of life in the planet. Water is capable of influencing the economy of a particular region and thus is considered as a very important economic entity. The concept of water as an economic good came up during the preparatory meetings for the Earth Summit in Rio de Janeiro of 1992. Despite all these significance, water remains to be most over exploited and underrated resource in the world. Due to indiscriminate and uncontrolled use of this resource, large amount water is wasted; domestic wastages leading the list. This study seeks to understand the domestic usage pattern, scarcity and conservation methods that prevail in the Dakshina Kannada district of Karnataka. A survey was conducted in the district to understand the domestic patterns and study of comprehensive reports and articles was carried out to interpret the primary data obtained. The principle of Domestic water conservation here is about the optimization of water in domestic households, keeping in mind the economic relevance of water. Thus optimization systems such as flow rate regulation system, greywater harvesting system and rainwater harvesting system are suggested in the district. Optimization should always first focus on evaluating the possibilities of multiple use of this resource, and thus reuse of water becomes a very effective and suggested method of conservation. The district which is predominantly agrarian based, where majority use groundwater as their source of water are also facing a groundwater depletion which is invisible but dangerous in long run. Thus measures such as well refill and rain water harvesting is promoted in the study.

Brain inspired memory prototypes, such as atomristors, are touted as next generation two terminal memories for neuromorphic computation. To make rapid progress toward developing such atomic scale memory, a facile technique to fabricate atomristor prototypes has to be developed. In this work, one such simple and lithography free technique to fabricate an atomristor prototype using photoexfoliated monolayer molybdenum di-sulfide (MoS2) is illustrated. Resistive switching characteristics of the atomristor were demonstrated by applying a write voltage pulse of 10 (SET) and −5 V (RESET) for 100 s between the active tantalum di-sulfide (TaS2) and inert indium tin oxide electrodes. During the SET process (ON state), the Ta2+ ions from the active electrode diffuse through monolayer MoS2 to create a number of parallel conducting channels. The persistence of the conducting channel even after removing the SET bias drives the atomristor to the low resistance state. On applying the “RESET” bias, the device resistance increased by a factor of five possibly due to the rupturing of the conducting channel. On cyclically applying the “SET” and “RESET” biases, the device was switched between low and high resistance states with excellent repeatability. Interestingly, it was also observed that the switching ratio increased on increasing the SET bias making this device a promising candidate for realizing tunable write once read many (WORM) memory devices.

The coexistence of negative photoconductivity and metallic-like behavior in conventional semiconductors is very uncommon. In this work, we report the existence of such unconventional physical properties in molybdenum disulfide nanoflowers (MoS2-NF). This is achieved by making the surface of MoS2 hygroscopic by alcohol treatment and creating a transport channel that favors protonic over electronic conduction. On cooling the MoS2-NF in a heat sink, the excess water that condenses on the surface forms a proton (H3O+) wire which exhibits pinched hysteresis characteristics. The conductivity of MoS2 increased by two orders of magnitude in the proton-dominated conduction regime with an exceptionally high positive temperature coefficient of 1.3 × 104 Ω K−1. Interestingly, MoS2-NF also exhibits strong negative photoconductivity at room temperature when illuminated with UV and infra-red radiation. This interesting behavior observed in MoS2 NF can be useful for energy harvesting applications and the realization of fast thermal memories and optical switches.

In this paper, we demonstrate thermal bi-stability and hysteresis in hetero-phase molybdenum diselenide (h-MoSe2) consisting of 2H semiconducting MoSe2 and molybdenum oxide (MoOx) phases. h-MoSe2 exhibits pinched hysteresis in the current-voltage characteristics, with the lobe area increasing with decreasing temperature. High and low resistance states were encoded into the sample by thermal manipulation. Cooling the sample below room temperature (RT) drives it to a low resistance state (“1” state), whereas heating above RT switches it to a high resistance state (“0” state). The ratio between “1” and “0” resistance states was found to be greater than 2000 with arbitrary long retention time at room temperature. The results are discussed in terms of temperature-induced adsorption/desorption of water vapor and its interplay with the charge transfer in MoSe2. Our study indicates that h-MoSe2 can be a potential candidate for application in alternate memory devices such as thermal memory and memristors.

Rapid prototyping of devices using exfoliated Molybednum di-Sulphide (MoS2) and Molybdenum di-Selenide (MoSe2) requires an experimental protocol for maximizing the probability of realizing flakes with desired physical dimension and properties. In this work, we analyzed the size and thickness distribution of MoS2 and MoSe2 single crystalline flakes exfoliated using anodic bonding technique and established a correlation between physical dimension of the flakes and the bonding parameters. Anodic bonding was carried out by applying a fixed voltage of 200 V with a set temperature of 150 °C for four different bonding time intervals. On analyzing the flake parameters from the four anodic bonded substrates using the optical and atomic force microscopy, it is found that the probability of getting flakes with large lateral size (>200 μm) increases as the bonding time interval is increased. Most of these large sized flakes have thickness of more than one hundred mono-layers and a tiny fraction of them have thickness of the order of few monolayers. A similar trend was also observed for MoSe2 single crystals. To demonstrate the feasibility of this technique in rapid prototyping, ultra thin MoS2 flakes was directly bridged between two ITO electrodes and their transport properties was investigated. Micro-Raman and photoluminescence studies were taken on selected regions of the thicker and thinner exfoliated flakes and their physical properties are compared.

Graphene-based nanomedicines are used to diagnosis disease and treatments including synthesis of prosthetic nerves, repairing of damaged nerve tissues, and nerve regeneration, specifically spinal cord injuries. Opportunities and challenges of biomedical applications of graphene in drug/gene delivery, cancer therapy, in vitro and in vivo imaging, and phototherapy are reviewed in this chapter. It has potential usage in bioelectronic limbs and visually impaired persons as retinal or ocular material. It is reviewed that graphene increases growth rate, distinguishes and rapidly increases stem cells; hence, it has a major role in biomedical engineering. Significant challenge is the thorough understanding of graphene–cell interactions, specifically, cellular uptake mechanisms. Investigation on graphene-based materials for cell culture is also an innovation. Such information facilitates the development of efficient graphene-based nanomedicines for promising developments in advanced biomedical fields.

Background: Ectopic pregnancy contributes significantly to maternal morbidity and mortality. There is a steady increase in the incidence of ectopic pregnancy over the past few decades, owing to rise in sexually transmitted infections, subfertility and its treatment with ART techniques. Objective of present work was to study the rate of ectopic pregnancy, associated risk factors, clinical course and management at SSIMS and RC.Methods: This is a retrospective study carried out at SSIMS and RC, Davangere from 01st January 2012 to 30th April 2017. A detailed analysis of case sheets done and all parameters analyzed. Institutional ectopic rate was calculated per 1000 deliveries.Results: Out of 43 women with ectopic gestation, 40 (93.02%) were tubal ectopic and 3 (6.98%) were ovarian ectopic. Institutional rate of ectopic is 11.54 per 1000 deliveries. STI’s are the commonest risk factor followed by subfertility. Diagnostic aid commonly used was pelvic ultrasound. There were no maternal deaths due to ectopic pregnancy. One third of the women presented with shock. 52.5% tubal and 66.6% ovarian ectopics were ruptured. All women with tubal ectopic were managed by salpingectomy either by open or laparoscopic method and ovarian ectopics managed by ipsilateral oophorectomy. Two-thirds of the women received blood transfusion and 5-7 days were required for post-operative recovery.Conclusions: Ectopic pregnancy is one of the commonest gynecological emergency and there is a yearly increase in the rate of ectopic. STI’s and subfertility are important risk factors. Prevention, early detection and treatment of STI’s may play an important role in reducing the rate of ectopic pregnancy.

Background: Intrauterine contraceptive device is one of the commonest form of long acting contraceptive method (LARC) adapted by reproductive aged women all over the world today. It can be used for 5 to 10 years depending on the type of the device. Aim of the study was to study the institutional rate of copper IUCD usage, rate of removal, side effect profile, indications for removal among women seeking contraception.Methods: The data regarding the usage of various temporary contraceptive methods were obtained from the family planning unit at our institution SSIMS&RC, Davangere from the records between Jan 1, 2012 to Dec 31, 2016 (5 years). A careful detailed study of records was done on the usage of Cu-IUCD.Results: During the five year study period, 3,767 women were provided with various forms of contraceptive methods. Cu-IUCD was the commonest method used by women accounting for 42.11% (1586 users). There was a decline in the rate of usage of Cu-IUCD in 2015-16, with increase in the usage of injectables. 179 women requested for removal in the study period, main reason being desire to become pregnant in 73.18% (131) users. Failure rate in the study period was 0.55%.Conclusions: Cu-IUCD is a safe and effective method of contraception adapted by women of reproductive age. The rate of removal is also low in our study. The decline in the usage of Cu-IUCD during our study period could be attributed to increasing awareness of other methods of LARC.