324,699 research outputs found
Design of molecularly imprinted polymers for sensors and solid phase extraction
No full textThis thesis presents broadly the applications of molecularly imprinted polymers in
sensors and solid phase extraction. Sensors for creatine and creatinine have been
reported using a novel method of rational design of molecularly imprinted polymers
(MIPs), and solid phase extraction of aflatoxin-B 1 has also been described in the
thesis.
A method for the selective detection of creataine and creatinine is reported in this
thesis, which is based on the reaction between polymerised hemithioacetal, formed by
allyl mercaptan, o-phthalic aldehyde, and primary amine leading to the formation of
fluorescent isoindole complex. This method was demonstrated for the detection of
creatine using creatine-imprinted MIPs. Since MIPs created using traditional methods
were unable to differentiate between creatine and creatinine, a new approach to the
rational design of a MIP selective for creatinine was developed using computer
simulation. A virtual library of functional monomers was assigned and screened
against the target molecule, creatinine, using molecular modeling software. The
monomers giving the highest binding score were further tested using simulated
annealing in order to mimic the complexation of the functional monomers with
template in the monomer mixture. The result of this simulation gave an optimised
MIP composition. The computationally designed polymer demonstrated superior
selectivity in comparison to the polymer prepared using traditional approach, a
detection limit of 25 μM and good stability. The 'Bite-and- Switch' approach
combined with molecular imprinting can be used for the design of assays and sensors,
selective for amino containing substances.
MEP for the selective binding properties for aflatoxin-B 1 was prepared using the
computational approach. The results obtained demonstrate that the MISPE offers a
simple, convenient and a rapid methodology for solid phase extraction of aflatoxin-B 1
even at very low concentrations of 2 ppb. The commercially available C-18 cartridges
were able to recover only about 52% of aflatoxin-B 1 at concentrations of 2 ppb when
compared with almost complete recovery by the MIP. We have proved here that,
MIPs as a solid phase extraction materials offer important and practical advantages
with respect to other solid phase extraction methodologies
S. Subrahmanyam : The Portuguese Empire in Asia 1500-1700. A Political and Economic History
No full textBouchon Geneviève. S. Subrahmanyam : The Portuguese Empire in Asia 1500-1700. A Political and Economic History. In: Bulletin de l'Ecole française d'Extrême-Orient. Tome 83, 1996. pp. 389-390
Las otras historias de Sanjay Subrahmanyam: entrevista
No full textHace unos días (o entradas) hablábamos del último libro de Serge Gruzinski, señalando su apuesta por la denominada "historia(s) conectada(s)". Aunque de pasada, mencionábamos también al historiador indio Sanjay Subrahmanyam, quizá el representante más genuino de esta corriente. Hace un tiempo, los amigos de La vie des idées le solicitaron una entrevista y, dado que el portal se ofrece en inglés y en francés, no se contentó con ser traducido, dada su condición políglota, sino que dio dos respu..
Sea surface height variability in the Indian Ocean from TOPEX/POSEIDON altimetry and model simulations
No full textSea Surface Height (SSH) variability in the Indian Ocean during 1993-1995 is studied using TOPEX/POSEIDON (T/P) altimetry data. Strong interannual variability is seen in the surface circulation of the western Arabian Sea, especially in the Somali eddy structure. During the Southwest (SW) monsoon, a weak monsoon year is characterized by a single eddy system off Somalia, a strong or normal monsoon year by several energetic eddies. The Laccadive High (LH) and Laccadive Low (LL) systems off southwest India are observed in the altimetric SSH record. The variability of the East India Coastal Current (EICC), the western boundary current in the Bay of Bengal, is also detected. Evidence is found for the propagation of Kelvin and Rossby waves across the northern Indian Ocean; these are examined in the context of energy transfer to the western boundary currents, and associated eddies. A simple wind-driven isopycnal model having three active layers is implemented to simulate the seasonal changes of surface and subsurface circulation in the North Indian Ocean and to examine the response to different wind forcing. The wind forcing is derived from the ERS-1 scatterometer wind stress for the same period as the T/P altimeter data, enabling the model response in different (active/weak) monsoon conditions to be tested. The model output is derived in 10-day snapshots to match the time period of the T/P altimeter cycles. Complex Principal Component Analysis (CPCA) is applied to both altimetric and model SSH data. This confirms that long Rossby waves are excited by the remotely forced Kelvin waves off the southwest coast of India and contribute substantially to the variability of the seasonal circulation in the Arabian Sea
“Why post more pictures if no one is looking at them?” Parents’ perception of the Facebook Like in sharenting
No full textThis paper reports on findings from an exploratory investigation about parents’ perceived role of the Facebook Like in sharenting (i.e., sharing about their children on social media) by drawing on the qualitative results of an online survey. Findings show that the majority of participants think that getting a Like on a picture of one’s child can encourage a parent to share more about him/ her because of two main understandings of this paralinguistic cue: the Like as a received validation of one’s parenting, or as a metric of connection with important people, causing emo- tional reactions in the receivers. Several parents, though, judge the Like as more commonly being important for others, explain- ing this difference in terms of internal characteristics. This study aims to extend our understanding of the motivations behind sharenting by taking into account the role of the Like in this practice and highlighting how parents position themselves in such an exchange of digital photo-sharing and feedback. As communication does not happen in a vacuum, we advance that research on parents’ photo-sharing behavior online may benefit from considering whether and how social media liking can foster and shape interpersonal communication between posters and recipients
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Difficulties of hydrofracturing in sandstone - experimental study
No full textHydrofracturing in sandstone is not an easy task. Sandstone is porous; fluid dissipation is common hence unable to obtain breakdown pressures in certain flow rates (0.0000005-0.0001 m3/s). The higher flow rate (0.00025 m3/s) is ascertained to determine the fracturing pressures. Due to this, fracture propagation and delineation are observed (Satya Subrahmanyam, 2022) [1]. To enhance, an experimental method is adopted by carrying out 6 Hydrofracturing tests in a borehole comprising sandstone. A high flow rate of 0.00025 m3/s and viscosity 0.001 Pa s is applied. Later, the fracture simulation was run on 12 core samples collected from the same depths in a lab. The fluid flow rates of 0.0000005-0.0000015 m3/s, viscosity 0.27 Pa- second, pore pressure of 4 MPa, confining pressures in vertical-12 MPa and horizontal 6, 18, 24, 30 MPa is applied. The fracture traces and the stress results exhibit a difference of 80°-300° observed in both cases. The major principle stress orientation obtained in the borehole is 20° and 40°. In lab tests with confining horizontal pressures at 6 and 18 MPa, it is 120° and 130°, and at 24 and 30 MPa is 20°. This indicated that there is fracture delineation occurred. It is observed in the higher flow rate and confining pressures
Carbon nanowalls amplify the surface-enhanced Raman scattering from Ag nanoparticles
No full textWe report surface-enhanced Raman scattering (SERS) from Ag nanoparticles decorated on thin carbon nanowalls (CNWs) grown by microwave plasma chemical vapor deposition. The Ag morphology is controlled by exposing the CNWs to oxygen plasma and through the electrodeposition process by varying the number of deposition cycles. The SERS substrates are capable of detecting low concentrations of rhodamine 6G and bovine serum albumin, showing much higher Raman enhancement than ordinary planar HOPG with Ag decoration. The major factors contributing to this behavior include: high density of Ag nanoparticles, large surface area, high surface roughness, and the underlying presence of vertically oriented CNWs. The relatively simple procedure of substrate preparation and nanoparticle decoration suggests that this is a promising approach for fabricating ultrasensitive SERS substrates for biological and chemical detection at the single-molecule level, while also enabling the study of fundamental SERS phenomena
- …
