43,938 research outputs found
Seminário sobre aquacultura 14 a 16 de dezembro de 1983
No full textA necessidade de desenvolver a aquacultura em Portugal obriga à escolha das espécies mais indicadas para tal finalidade. A propósito o autor chama a atenção para as graves consequências que podem advir das introduções e/ou transferências de animais aquáticos, quer para as espécies locais e meio ambiente, como para a para a saúde pública.Concerning the need to choose the most convenient species to cultivate in order to implement aquaculture in Portugal, the author draws the attention to the deleterious consequences of introductions and transfers of aquatic animals.Caixa Geral de Depósito
Virender Sehwag and Cricket’s Existential Anxiety
No full textThe article is in the nature of a personal interpretation of the illustrious career of former Indian batsman Virender Sehwag. Known for his swashbuckling stroke play, he found his niche at the top of the famed Test batting line up that once boasted of the likes of Rahul Dravid, Sachin Tendulkar, V.V.S. Laxman and Saurav Ganguly, despite unanimous opinion of critics about the glaring deficiencies in his batting technique. His rather inconsistent returns in limited overs cricket run counter to the conventional wisdom that associates the ‘copybook style’ of batting with greater successes in the longest format of the sport. The article is less of an attempt to a statistical analysis of the batsman for reaching a quantitative explanation for the said ‘anomaly’ in his performances, and more of an enquiry into his ‘inner world’ as a batsman, offering a metaphorical insight into the existential dichotomy of the longer and shorter formats of cricket. The author draws from the perspective of Danish theologian Soren Kierkegaard on anxiety and that of American anthropologist Ernest Becker on neurosis, reflecting on the various manifestations of despair that haunt batsmen across formats, as a window to Sehwag’s unique defences in dealing with the anxieties at the batting crease. In this quest, the author expresses concerns about the future of the game in the backdrop of the slippery slope of the age-old existential dilemma facing the governing body of the sport in its bid to go truly global
Instrumental approach toward understanding nano-pollutants
No full textNano-pollutants (NPLTs) have recently raised global concerns due to their possible harmful impact on environment and human health. However, until date, information on the occurrence, fate and toxicity of NPLTs in environment is scant. The knowledge gap can be attributed to the lack of advanced and sophisticated methodologies for the precise detection and characterization of NPLTs at lower concentration in complex matrices, such as surface water, wastewater, soil and food. This review briefly discusses the performance of classical methods for characterization and study of the properties of NPLTs. The important properties include shape, size, aggregation state, chemical composition and structure. Chromatographic, microscopic and spectroscopic techniques have been developed for detection and quantitative estimation of fabricated or naturally existed NPLTs in different matrices. Often, combination of these techniques is required for the separation, purification and accurate estimation. For better detection and understanding of the initial steps of interaction with the environmental matrices, pollution sources, such as wastewater and industrial discharges, must be selected as sampling points. Understanding the dynamics of agglomeration, and decantation will allow to estimate the plume of transport to delimit the potential effects.Fil: Naghdi, Mitra. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Metahni, Sabrine. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Ouarda, Yassine. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Brar, Satinder Kaur. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Das, Ratul Kumar. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Cledón, Maximiliano. Institut National de la Recherche Scientifique; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional del Comahue- Prov de Rio Negro- Conicet; Argentin
Redox-Responsive Nanocapsules for the Spatiotemporal Release of Miltefosine in Lysosome: Protection against Leishmania
No full textLeishmaniasis, a vector-borne disease, is caused by intracellular parasite Leishmania donovani. Unlike most intracellular pathogens, Leishmania donovani are lodged in parasitophorous vacuoles and replicate within the phagolysosomes in macrophages. Effective vaccines against this disease are still under development, while the efficacy of the available drugs is being questioned owing to the toxicity for nonspecific distribution in human physiology and the reported drug-resistance developed by Leishmania donovani. Thus, a stimuli-responsive nanocarrier that allows specific localization and release of the drug in the lysosome has been highly sought after for addressing two crucial issues, lower drug toxicity and a higher drug efficacy. We report here a unique lysosome targeting polymeric nanocapsules, formed via inverse mini-emulsion technique, for stimuli-responsive release of the drug miltefosine in the lysosome of macrophage RAW 264.7 cell line. A benign polymeric backbone, with a disulfide bonding susceptible to an oxidative cleavage, is utilized for the organelle-specific release of miltefosine. Oxidative rupture of the disulfide bond is induced by intracellular glutathione (GSH) as an endogenous stimulus. Such a stimuli-responsive release of the drug miltefosine in the lysosome of macrophage RAW 264.7 cell line over a few hours helped in achieving an improved drug efficacy by 200 times as compared to pure miltefosine. Such a drug formulation could contribute to a new line of treatment for leishmaniasis.A. Das acknowledges SERB (India) Grants (CRG/2020/000492 and JCB/2017/000004) and DBT Grant (BT/PR22251/NNT/28/1274/2017) for supporting this research. N. Mukherjee acknowledges SERB (India) Grant PDF/2016/001437 and K. Das acknowledges the grant EMR/2015/001674 for supporting this research. Financial support from DST (DST/INSPIRE/03/2017/002477) is acknowledged by R.T. This manuscript bears CSMCRI registration no 7/2021.Pramanik, SK (corresponding author), CSIR Cent Salt & Marine Chem Res Inst, Bhavnagar 364002, Gujarat, India.
Mukherjee, N (corresponding author), CSIR Indian Inst Chem Biol, Canc Biol & Inflammatory Disorder Div, Kolkata 700032, India.
Chattopadhy, S (corresponding author), BITS Pilani, Pilani 403726, Goa, India.
Das, A (corresponding author), Indian Inst Sci Educ & Res Kolkata, Mohanpur 741246, W Bengal, India.
[email protected]; [email protected]; [email protected]
Interview with Indra Das
No full textIndra Das is most well-recognized as the author of The Devourers (2015), a novel that won the Lambda Literary Award for straddling the genres of sci-fi, speculative, and fantasy fiction alongside LGBT themes. Das’s short fiction is widely published is horror and sci-fi anthologies, as well as magazines like Tor.com, Strange Horizons, and Asimov’s Science Fiction. He spoke candidly with Alok Amatya over email about the current literary landscape, the work of writing transgressive genre fiction, and his own experiences as an upcoming global author
Experimental studies on creping and its influence on mechanical properties of tissue paper products
No full textTissue papers are softer, stretchier, and more water absorbent than regular writing or packaging paper products. Creping of an adhesively bonded low-density paper web from the surface of a rotating Yankee drum is the key manufacturing technique in tissue production. Creping dedensifies and weakens the paper by partially damaging the fibers and the inter-fiber bonds in the fiber network. The process also imparts a signature microstructure, called crepe structure, to the tissue paper. Tissues thus produced have a high specific volume (bulk to basis weight ratio), work to rupture, failure strain (stretch), softness and absorbency. Mechanical properties of tissues are governed by the creping process. Therefore, a scientific understanding of the creping process, and its impact on the structural and mechanical properties of the tissue paper is important.
The present research approaches the highly complex problem from an experimental perspective, with a view to complement ongoing physics based numerical models to simulate creping. Experimental techniques are developed to visualize the high speed creping process, quantify the crepe structure, and finally understand the influence of the crepe structure on the uni-axial tensile response of the tissue. A novel surface imaging based structural quantification technique is developed and successfully demonstrated on a commercial tissue machine. The surface image based quantification technique is also validated by micrographic observations of the tissue cross section under a Scanning Electron Microscope (SEM). This work lays the foundational techniques and protocols for future studies in the laboratory and opens the opportunity to observe crepe structure in real time for quality and process control.
The surface imaging techniques are then used to observe the evolution of the creping microstructure under a tensile load. Local two dimensional strain fields are quantified using Digital Image Correlation (DIC) to gain insight into failure mechanisms at the macroscopic network level. Micro tensile tests are conducted under SEM to gain further insight into the deformation and failure mechanisms operative at fiber length scales. The studies showed the impact of the creping structure, formation, and inter fiber bonds on the tensile response of the tissue paper, specifically along machine direction.Applied Science, Faculty ofMechanical Engineering, Department ofGraduat
Despiking of Turbulent Flow Data in Gravel Bed Stream
No full textThe present experimental study insights the decontamination of instantaneous velocity fluctuations captured by Acoustic Doppler Velocimeter (ADV) in gravel-bed streams to ascertain near-bed turbulence for low Reynolds number. The interference between incidental and reflected pulses produce spikes in the ADV data especially in the near-bed flow zone and therefore filtering the data are very essential. Nortek’s Vectrino four-receiver ADV probe was used to capture the instantaneous three-dimensional velocity fluctuations over a non-cohesive bed. A spike removal algorithm based on the acceleration threshold method was applied to note the bed roughness and its influence on velocity fluctuations and velocity power spectra in the carrier fluid. The velocity power spectra of despiked signals with a best combination of velocity threshold (VT) and acceleration threshold (AT) are proposed which ascertained velocity power spectra a satisfactory fit with the Kolmogorov “–5/3 scaling-law” in the inertial sub-range. Also, velocity distributions below the roughness crest level fairly follows a third-degree polynomial series
"PULS." - Ein Blog als Online-Magazin für Medizinstudierende der Goethe-Universität Frankfurt
No full textIm Herbst 2009 forderten Studierende im Rahmen landesweiter Proteste auch am Fachbereich Medizin/Zahnmedizin der Goethe-Universität Frankfurt mehr Transparenz und Kommunikation zu Angelegenheiten ihres Studiums. Einen innovativen Lösungsansatz, um diesen Forderungen nachzukommen, bietet eines der Web 2.0 Werkzeuge: ein auf einer Blog-Software basierendes Online-Magazin für Studierende und andere Mitglieder des Fachbereichs.
Das öffentlich zugängliche Online-Magazin "PULS." (https://newsmagazin.puls.med.uni-frankfurt.de/wp/) wird mit einer freien Blog-Software (wordpress Version 3.1.3.) realisiert und von einer Online-Redakteurin konzipiert und geschrieben. Die Beiträge entstehen nach eigenen Recherchen sowie aus Anregungen und Gesprächen mit verschiedenen Personengruppen des Fachbereichs. Die datenschutzkonforme Auswertung der Zugriffe erfolgt über eine open-source Webanalyse-Software (Piwik). Zusätzlich werden jährlich mit dem Online-Umfrage-Tool Survey Monkey die Nutzer anonym befragt.
"PULS." ist seit dem 14.02.2010 ununterbrochen online und hat seitdem 806 Beiträge (Stand: 27.11.2012) publiziert und wird von ca. 2400 Besuchern monatlich gelesen. Das Themenspektrum ist zentriert auf die Anliegen der Frankfurter Medizin- und Zahnmedizinstudierenden. Die enge Zusammenarbeit mit verschiedenen Gruppierungen des Fachbereichs – Dekanat, Studierende und Lehrende – garantiert darüber hinaus ein fachbereichs-relevantes Themenspektrum. Das Online-Magazin begleitet komplexe Projekte und Entscheidungen mit Hintergrundinformationen und kommuniziert sie verständlich. Eine jährliche Nutzer-Evaluierung zeigt eine wachsende Leserzahl und eine sehr hohe Zustimmung für das Online-Magazin, seine Inhalte und seinen Stil. Das Web 2.0-Medium "Blog" und seine web-typische Sprache entsprechen dem Medienverhalten der Zielgruppe, d.h. den Studierenden des Fachbereichs Medizin.
"PULS." hat sich als ein geeignetes und strategisches Instrument erwiesen, um größere Transparenz, mehr Kommunikation und letztendlich eine stärkere Identifikation der Studierenden mit ihrem Fachbereich voranzutreiben
Topologies, Modeling, and Control of Hybrid Switched-Capacitor Converters
No full textThis dissertation explored the ideas and concepts for hybrid switched capacitor converter topologies and new power delivery architectures to provide viable solutions for high conversion ratio DC-DC and AC-DC applications. A new Multi Inductor Hybrid (MIH) Converter family for high conversion ratio DC-DC applications has been synthesized and analyzed to provide non-isolated DC-DC conversions with large voltage conversion ratios efficiently. The highlight of this converter family is a 6-level 6-phase 6-inductor MPMIH converter, which achieved 90.7% peak efficiency with a load range of 0-220A at 1V and 1kA/in^3 density.A new modeling method reveals that all odd-level Flying Capacitor Multi-Level converters become current sources with non-ideal timing while the even-level converters stay as voltage sources. A method for identifying unbalanced hybrid converters is also provided.This dissertation demonstrates a two-stage power delivery architecture to bridge AC distribution voltages to core levels for computing loads in data centers. In combination, direct conversion from \textasciitilde110 VAC to 1VDC achieves a peak efficiency of 84.1% while providing output currents up to 160A. Partial power processing for AC/DC applications has been explored with a switched-capacitor (SC) based hybrid step-down converter and its new control techniques. The operation with multiple modules is verified with a 115VAC-to-48VDC conversion and 200VAC input to two 48VDC outputs.A new modular isolated DC-DC converter is proposed and demonstrated for point-pf-load (POL) applications with partial power processing. A prototype of the modular architecture has been demonstrated for a 100V-to-3V point-of-load conversion with a maximum load of 60A. The peak efficiency of 91% is achieved at 57W/20A output. A new multi-inductor multi-output hybrid converter is also proposed and demonstrated. The MiMoH converter prototype has been implemented to demonstrate conversion from a 24-48V input voltage to three individually regulated outputs ranging from 1.2V to 2.2V. The converter prototype achieves 40W peak power and 91.8% peak efficiency. The topologies presented in this dissertation, corroborated with control and modeling techniques, demonstrated superior performance, natural balancing ability, and relatively easy controllability, making them excellent candidates for more compact and efficient system design
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