PERFORMANCES ASSESSMENT OF NATURAL REFRIGERANTS AS SUBSTITUTES TO CFC AND HCFC IN HOT CLIMATE

Due to the environmental concerns ozone depletion potential (ODP) and global warming potential (GWP) of the existing refrigerants, industry and researchers in this field are investigating long-term solutions. With extensive work on alternatives to chlorofluorocarbons (CFCs) and hydro chlorofluorocarbons (HCFCs), initially hydro fluorocarbons were considered to be long-term solutions. The global warming of HFCs has become a hurdle to accept them as long-term solutions. Now, the focus is on the use of natural refrigerants like hydrocarbons (HCs) such R290, R600, ammonia, carbon dioxide and water. These natural substances have very low GWP, and a zero ODP. This paper presents simulation results through a thermodynamic analysis of R22 and three of its alternatives natural refrigerants (R290, R600a and R717) for A/C and refrigeration purposes operating under various outdoor temperatures, represented by the condenser temperatures. The examined new refrigerants show varying performance, depending on the evaporator temperatures, but in every case, the condenser temperature seems to have an important impact on the performance of the cycle

Design of Low Leakage Multi Threshold (Vth) CMOS Level Shifter

In this paper, a low leakage multi Vth level shifter is designed for robust voltage shifting from sub threshold to above threshold domain using MTCMOS technique and sleepy keeper. MTCMOS is an effective circuit level technique that improves the performance and design by utilizing both low and high threshold voltage transistors. Leakage power dissipation has become an overriding concern for VLSI circuit designers. In this a “sleepy keeper” approach is preferred which reduces the leakage current while saving exact logic state. The new  low-power level shifter using sleepy keeper is compared with the previous work for different values of the lower supply voltage. When the circuits are individually analyzed for power consumption at 45nm CMOS technology, the new level shifter offer significant power savings up to 37% as compared to the previous work. Alternatively, when the circuits are individually analyzed for minimum propagation delay, speed is enhanced by up to 48% with  our approach to the circuit. All the simulation results are based on 45nm CMOS technology and  simulated in cadence tool.DOI:http://dx.doi.org/10.11591/ijece.v3i5.316

INFLUENCE OF INDIAN PHILOSOPHY ON HERMAN HESSE AND ELEMENTS OF AUTOBIOGRAPHY IN SIDDHARTHA

Influence of Indian philosophy on Herman Hesse and elements of autobiography in Siddhartha. The novel reflects  Hesse’s preoccupation with India at a time of personal crisis and his search for complete freedom which he could not find in his Occidental sensibilities which he found too intellectual and far from reality. Hesse’sfinal conclusion on religion and his idea of enlightenment are beautifully assimilated in this masterpiece which is widely read in American curriculum. The article looks at  Hesse’s life and events which propelled him to write  Siddhartha and his own view which finds voice in his protagonist  Siddhartha. The novel in many ways is autobiographical and analysis the inner struggle of a man brought up in a comfortable house but takes up individualistic path to find salvatio

A Low Power 32 Bit CMOS ROM Using A Novel ATD Circuit

A low power high speed 32 Bit ROM circuit implemented on 0.18µm CMOS process has been presented in this paper. The circuit is build using a parallel ROM core structure and runs on 1.8 V supply voltage. A novel Address Transition Decoder (ATD) circuit is proposed which energizes the ROM components such as Row Decoder, Column Decoder, ROM core etc, for short time intervals when there is a transition in input address bits. The power consumed in ROM with proposed ATD circuit is 0.78 mW, which corresponds to 82.27% reduction in power as compared to ROM without ATD circuit (4.46 mW). At the output almost full signal swing has been achieved without using any sense amplifier. The implemented ROM has a very low latency of 0.56 ns.DOI:http://dx.doi.org/10.11591/ijece.v3i4.316

Knowledge, attitude and practices of rural medical practitioners on generic medicines

Background: An unqualified medical practitioner without any formal registration and practicing allopathic medicine in rural areas in India can be called Rural Medical Practitioner (RMP). RMPs enjoy a great deal of practice in rural areas by taking advantage of lacunae in the public health system. Government of India is currently popularising generic medicines, but still certain doubts exist even among doctors and how far the RMPs are aware of generic medicines is a big issue. They influence a lot of uneducated people, so the knowledge, attitude and practices they follow have a large impact on society.Methods: A cross sectional, prospective study was undertaken to assess the knowledge, attitude and the practices of 152 RMPs on generic medicines for a period of three months. A 23-item questionnaire was well designed, pre-validated and distributed to RMPs in and around Guntur district. The results were analysed using descriptive statistics.Results: 92% of the participants were aware of generic drugs. More than 80% believed that they are equivalent in terms of efficacy and safety to their branded counterparts and are available at reasonable prices. 95.4% RMPs believed that prescribing generic drugs will decrease the pharmaco-economic burden of the country. Almost all of them agreed on the need for the updates and education on generics by means of continuing medical education (CMEs).Conclusions: The participants had good amount of knowledge on generic drugs but there are concerns regarding quality and therapeutic efficacy of generic drugs. Proper awareness about the generic prescription practice may improve the patient compliance by reducing economic burden to the patients

High Performance Low Power Dual Edge Triggered Static D Flip-Flop

In this paper a low-power double-edge triggered static flip-flop (DETSFF) suitable for low-power and high performance applications is presented. The designed DETFF is verified at gpdk 180nm-1.8V CMOS technology. Comparison with some of the latest DETFFs shows that the proposed DETSFF can achieve the lowest power consumption, lowest clock to Q delay and thus Power-delay-product (PDP). Moreover, the proposed DETSFF comprises of only 15 transistors hence require lesser number of transistors and thus requires lesser overall silicon area.DOI:http://dx.doi.org/10.11591/ijece.v3i5.316

Tubulin isoform composition tunes microtubule dynamics

Microtubules polymerize and depolymerize stochastically, a behavior essential for cell division, motility and differentiation. While many studies advanced our understanding of how microtubule-associated proteins tune microtubule dynamics in trans, we have yet to understand how tubulin genetic diversity regulates microtubule functions. The majority of in vitro dynamics studies are performed with tubulin purified from brain tissue. This preparation is not representative of tubulin found in many cell types. Here we report the 4.2Å cryo-EM structure and in vitro dynamics parameters of α1B/βI+βIVb microtubules assembled from tubulin purified from a human embryonic kidney cell line with isoform composition characteristic of fibroblasts and many immortalized cell lines. We find that these microtubules grow faster and transition to depolymerization less frequently compared to brain microtubules. Cryo-EM reveals that the dynamic ends of α1B/βI+βIVb microtubules are less tapered and that these tubulin heterodimers display lower curvatures. Interestingly, analysis of EB1 distributions at dynamic ends suggests no differences in GTP cap sizes. Lastly, we show that the addition of recombinant α1A/βIII tubulin, a neuronal isotype overexpressed in many tumors, proportionally tunes the dynamics of α1B/βI+βIVb microtubules. Our study is an important step towards understanding how tubulin isoform composition tunes microtubule dynamics

Microtubule-severing enzymes: From cellular functions to molecular mechanism.

Microtubule-severing enzymes generate internal breaks in microtubules. They are conserved in eukaryotes from ciliates to mammals, and their function is important in diverse cellular processes ranging from cilia biogenesis to cell division, phototropism, and neurogenesis. Their mutation leads to neurodegenerative and neurodevelopmental disorders in humans. All three known microtubule-severing enzymes, katanin, spastin, and fidgetin, are members of the meiotic subfamily of AAA ATPases that also includes VPS4, which disassembles ESCRTIII polymers. Despite their conservation and importance to cell physiology, the cellular and molecular mechanisms of action of microtubule-severing enzymes are not well understood. Here we review a subset of cellular processes that require microtubule-severing enzymes as well as recent advances in understanding their structure, biophysical mechanism, and regulation

Histology Personal Trainer: Identifying Tissue Types Using Critical Thinking and Metacognition Prompts

Tissue-type histology is a foundational lab exercise for many courses… and our students hate it. In anatomy and physiology, where more obviously applicable labs are just around the corner, students struggle to grasp this basic content. At this institution, a Hispanic-serving, two-year community college, scores are historically lowest on the histology exam and many students drop the course after this exam. Attrition is a problem nationally as well; while community colleges train about 60% of healthcare workers, attrition rates in anatomy and physiology courses are nearly 50%. Upon closer investigation of this exam, we found students were attempting to memorize the provided field of view, rather than identifying tissue hallmarks, and therefore struggled to apply their skills during the exam