100 research outputs found
Concentration in Knowledge Output: A case of Economics Journals
No full textThis paper assesses the degree of author concentration in seven economics journals, which were published in India during 1990-2002. To measure the degree of author concentration, Lotka's Law was used. Moreover, we also make an exploratory analysis of the geographic, economics subfield and institutional concentration in 704 economics journals. An important finding of this paper is that specialized journals in the sample report the highest degree of author concentration. This result is quite similar to the findings by Cox and Chung (1991). Furthermore, there are several instances showing that the journals lean towards certain norms; this may affect the flow of innovative ideas into economics. We conclude that a knowledge activity, involving the high degree of concentration and a biased publication process, may affect the flow of new ideas into the discipline.Concentration, Lotka's Law
Fish distribution dynamics in the Aghanashini estuary of Uttara Kannada, west coast of India
No full textFish diversity (77 species) in the Aghanashini River estuary of the Indian west coast is linked to variable salinity conditions and zones I, II and III for high, medium and low salinity respectively. Zone I, the junction between Arabian Sea and the estuary, had all species in yearly succession due to freshwater conditions in monsoon to high salinity in pre-monsoon. The medium (zone II) and low (zone III) salinity mid and upstream portions had maximum of 67 and 39 fish species respectively. Maintenance of natural salinity regimes in estuary, among other ecological factors, is critical for its fish diversity
BIOGRAPHY OF T.V.SAMBASIVAM PILLAI AND AN ANALYSIS OF HIS CONTRIBUTION TO THE SIDDHA SYSTEM OF MEDICINE
No full textT.V.Sambasivam pillai, the acclaimed author, of the Cyclopaedic Dictionary is well known in the field of Indian Medicine especially Siddha medicine. Cyclopaedic Dictionary is considered as one of the great treasures of the Siddha system. Neither did he possess a basic medical degree nor he hailed from a family with medical background but his depth of knowledge in the Siddha system is highly commendable. He spent his entire life contributing and deciphering the ancient literatures of the Siddha system. This article is a tribute to his dedication, aspiration, devotion, and sacrifice for the Siddha system of Medicine and aids in highlighting the excerpts of the Cyclopaedic Dictionary
Analysis of Local Field Potential and Gamma Rhythm Using Matching Pursuit Algorithm
No full textSignals recorded from the brain often show rhythmic patterns at different frequencies, which are tightly coupled to the external stimuli as well as the internal state of the subject. These signals also have transient structures related to spiking or sudden onset of a stimulus, which have a duration not exceeding tens of milliseconds. Further, brain signals are highly non-stationary because both behavioral state and external stimuli can change over a short time scale. It is therefore essential to study brain signals using techniques that can represent both rhythmic and transient components of the signal. In Chapter 2, we describe a multi-scale decomposition technique based on an over-complete dictionary called matching pursuit (MP), and show that it is able to capture both sharp stimulus-onset transient and sustained gamma rhythm in local field potential recorded from the primary visual cortex.
Gamma rhythm (30 to 80 Hz), often associated with high-level cortical functions, has been proposed to provide a temporal reference frame (“clock”) for spiking activity, for which it should have least center frequency variation and consistent phase for extended durations. However, recent studies have proposed that gamma occurs in short bursts and it cannot act as a reference. In Chapter 3, we propose another gamma duration estimator based on matching pursuit (MP) algorithm, which is tested with synthetic brain signals and found to be estimating the gamma duration efficiently. Applying this algorithm to real data from awake monkeys, we show that the median gamma duration is more than 330 ms, which could be long enough to support some cortical computations
Vaccination hesitancy among healthcare professionals : a Literature Review
No full textThis thesis aims to help healthcare professionals understand common beliefs about vaccines and which factors can influence people’s vaccination decisions. The study looks at healthcare professionals’ general opinions about vaccines, where they get their information, and how cultural background, among other things, affects vaccine hesitancy, criticism, and acceptance. By understanding the factors influencing vaccine hesitancy and beliefs, healthcare professionals can be supported and educated to better support their patients about vaccines in the future. This thesis reviews existing research and uses data from trusted academic and evidencebased sources. A literature review was used to understand better the reasons for healthcare professionals' attitudes and decisions. The data was analyzed by using twentyfive articles inductive content analysis, which looks for common patterns and themes. The results showed that healthcare professionals' beliefs and cultural backgrounds significantly influence how they view vaccines. This was reflected in vaccination rates, opinions found in the research, and how willing health professionals were to take certain vaccines. Beliefs were shaped by media messages, fear of side effects, lack of trust in health authorities, and how public health officials communicated about vaccines. Because of this, healthcare professionals should aim to have open, respectful conversations with patients. Listening to their concerns and understanding their background can help build trust and encourage more people to feel safe and confident about getting vaccinated.
Keywords: Vaccination review; vaccine hesitancy; vaccination attitudes; behavior; vaccination hesitancy in healthcare professionals
Dietary and digestive differences in primates at Singapore zoo – inter and intra-specific body size in relation to feed preference, intake, digesta retention and nutrition.
No full textDifferences in body sizes of primates can be a factor for variation in their dietary and digestive strategies. Five captive primate species of Singapore Zoo were selected to examine intra- and inter-specific body size relationships with feed intake, nutrition, digesta retention and feed preference. For five consecutive days per species, individual feed items were weighed before and after consumption for average feed intake per day, with average caloric and dry matter intakes per day calculated from nutritional analysis’ results. Nutritional analysis was performed for consumed, preferred and non-preferred feed items. Digesta passage rates were determined. Results showed that intra-specific differences were absent. Inter-specific body size correlated negatively with caloric intake, while no correlation was found with dry matter intake. Inter-specific body size correlated positively with protein intake, protein-ADF and protein-NDF ratios within folivores. It correlated negatively with fat, ADF and NDF intakes within frugivores. Neither TT nor MRT showed significant correlations with inter-specific body size. Feed preference results revealed that no marked selection for food of certain nutritional qualities exists in the captive primates. Overall, body size alone was not a good predictor for dietary and digestive differences found in primates, although it was still a factor among others.Bachelor of Science in Biological Science
FORMULATION AND EVALUATION OF GLIMEPIRIDE-LOADED LIPOSOMES BY ETHANOLINJECTION METHOD
No full textABSTRACTObjective: The objective of present study deals with an attempt to formulate Glimepiride in liposomal drug delivery system, in order to maintainsteady state plasma concentration; hence it has to be administered frequently to the patients, because of its short plasma half life. To maintain steadyplasma concentration for longer period of time formulation of controlled drug release system is essential. Liposomal drug delivery system providessustained release of Glimepiride.Methods: Glimepiride liposomes were prepared by ethanol injection method using varying concentration of cholesterol and lecithin. Drug excipientcompatibility study was performed by FT-IR spectral studies and differential scanning calorimetry studies. Liposomes were evaluated for drugencapsulation efficiency, morphological study by optical microscope, SEM and TEM, vesicle size and zeta potential determination, In -vitro drugrelease & kinetic study and stability studies.Results: The formulations fulfilled all official requirements. The drug release was slow and sustained for >12 hrs. The formulations followed zeroorder kinetics. Zeta potential and stability study for 90 days demonstrated that the formulation was stable at 25¬¬¬¬oC than when refrigerated.Conclusion: Glimepiride was formulated as liposomal formulation after checking the compatibility by DSC and FT-IR studies. The liposomespreparation FA3 was optimized based on the particle size, zeta potential, entrapment efficiency, and drug release characteristics.Keywords: Liposomes, Antidiabetic, Glimepiride, Ethanol-injection method
Carrier multiplication in van der Waals layered transition metal dichalcogenides
No full text© 2019, The Author(s).Carrier multiplication (CM) is a process in which high-energy free carriers relax by generation of additional electron-hole pairs rather than by heat dissipation. CM is promising disruptive improvements in photovoltaic energy conversion and light detection technologies. Current state-of-the-art nanomaterials including quantum dots and carbon nanotubes have demonstrated CM, but are not satisfactory owing to high-energy-loss and inherent difficulties with carrier extraction. Here, we report CM in van der Waals (vdW) MoTe2 and WSe2 films, and find characteristics, commencing close to the energy conservation limit and reaching up to 99% CM conversion efficiency with the standard model. This is demonstrated by ultrafast optical spectroscopy with independent approaches, photo-induced absorption, photo-induced bleach, and carrier population dynamics. Combined with a high lateral conductivity and an optimal bandgap below 1 eV, these superior CM characteristics identify vdW materials as an attractive candidate material for highly efficient and mechanically flexible solar cells in the future11sciescopu
Lotka' s Law, Co-authorship and Interdisciplinary Publishing
No full textThe robustness or breakdown of Lotka's law about the frequency distribution of scientific productivity depends on scientific cooperation, counting methods, interdisciplinary publishing and selection methods for sample collections. We have chosen to analyse the relationship using Mandelbrot's equivalent distribution model because this model is sensitive and uses the original data (scores). Five sets of authors and publications, the two sets used by Lotka, a set from High Energy Physics, a set from Microbiology and a set based on applicants to a research programme promoting young researchers have been used. It is shown that even for a sample of authors in High-Energy Physics with extremely strong co-authorship, Mandelbrot's distribution law is robust when complete-normalized (fractional) counting is used whereas complete counting results in a breakdown. In the field of Microbiology with much weaker cooperation, both counting methods result in a breakdown of Mandelbrot's law. Today a field like Microbiology with the corresponding set of journals, probably has a large content of interdisciplinary publishing and therefore no more fulfills the precondition of Lotka's law, that the total production of the authors (sources) is considered. For a set of applicants for the Emmy Noether Programme of the German Research Foundation. Mandelbrot's law breaks down despite the fact that all publications co-authored by the applicants are taken into account. In agreement with Bayes' theorem of conditional probabilities these results lead to the conjecture that any selection process of authors and/or publications causes a breakdown of Mandelbrot's law and, as a consequence Lotka's law
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