Colorism and Love for Fair Skin : Exploring Digitization’s Effect on India’s Arranged Marriage Matrimonial Advertisements

Dhiman Chattopadhyay,Sriya Chattopadhyay 한국언론학회 2019 Asian Communication Research Vol.16 No.1

Previous studies have found the presence of colorism, especially a bias toward fair-skinned women in India’s newspaper matrimonial advertisements where fair-complexioned women are considered more beautiful than those with a darker skin complexion. Most matrimonial advertisements in newspapers are posted by family elders such as parents of prospective brides. This study explored if the rise of online matrimonial portals has empowered marginalized members of families such as prospective brides by giving them greater access to, and control over, posting matrimonial ads, and whether who posts these ads has made a difference to how women are projected in the online ads. Textual analysis of 150 online matrimonial ads indicated that younger women such as would-be brides posted more ads in online media, compared to older family members. Further, irrespective of who posted the ads, there was less overt focus on physical attributes of women such as fairness of skin, but colorism was present in more subtle forms. Finally, the online ads posted by both prospective brides, and their parents, were unable to entirely break free from shackles of socially constructed patriarchal norms where women’s physical attributes such as fair skin are considered critical qualities. Findings were consistent with the tenets of Critical Race Theory that colorism is an ingrained feature of social systems and is constantly negotiated based on a group’s own social interests.

Patterning of Thin Copper Films under UV Exposure in Chlorine-Based Liquids

Chattopadhyay K.K.,안일신,Cho Jongkyu,Kim Okkyung,Kwak Jiwoon,Kyoung Jaisun 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

Wet etching of thin copper films was achieved by using chlorine-based liquids, such as 1,2- dicholorethane or NaCl dissolved in water, under ultraviolet (UV) irradiation. The etching of the thin copper film was probed in-situ by using a spectroscopic ellipsometer, and the etch rate could be controlled by adjusting the exposure parameters. As UV is used in lithography, mask patterns can be transferred to a copper surface directly without resorting to a complex photoresist process. Easy control of the etch rate ranging from sub °A/s and use of nontoxic liquids such as 1,2-dicholoroethane and NaCl solution are major advantages of this novel technique.

Optically Controlled Silicon MESFET Fabrication and Characterizations for Optical Modulator/Demodulator

Chattopadhyay, S.N.,Overton, C.B.,Vetter, S.,Azadeh, M.,Olson, B.H.,Naga, N. El The Institute of Electronics and Information Engin 2010 Journal of semiconductor technology and science Vol.10 No.3

An optically controlled silicon MESFET (OPFET) was fabricated by diffusion process to enhance the quantum efficiency, which is the most important optoelectronic device performance usually affected by ion implantation process due to large number of process induced defects. The desired impurity distribution profile and the junction depth were obtained solely with diffusion, and etching processes monitored by atomic force microscope, spreading resistance profiling and C-V measurements. With this approach fabrication induced defects are reduced, leading to significantly improved performance. The fabricated OPFET devices showed proper I-V characteristics with desired pinch-off voltage and threshold voltage for normally-on devices. The peak photoresponsivity was obtained at 620 nm wavelength and the extracted external quantum efficiency from the photoresponse plot was found to be approximately 87.9%. This result is evidence of enhancement of device quantum efficiency fabricated by the diffusion process. It also supports the fact that the diffusion process is an extremely suitable process for fabrication of high performance optoelectronic devices. The maximum gain of OPFET at optical modulated signal was obtained at the frequency of 1 MHz with rise time and fall time approximately of 480 nS. The extracted transconductance shows the possible potential of device speed performance improvements for shorter gate length. The results support the use of a diffusion process for fabrication of high performance optoelectronic devices.

Modeling and Analysis of Warranty Cost for 2D-Policies Associated with Sale of Second-hand Products

Chattopadhyay G.,Yun Won-Young The Korean Reliability Society 2006 International Journal of Reliability and Applicati Vol.7 No.1

The market for second hand products has been growing for a variety of reasons (e.g., new products appearing at a faster rate and the expected life of products increasing due to rapid advances in technology). The demand for warranties for second-hand products has been growing along with the growth of the market for second-hand products. Warranty for new products (consumer durables, industrial and commercial, and specialized defense products) has received a lot of attention. In contrast, warranties for second-hand product have received very little attention. Often, dealers of second-hand product such as cars offer 2D-warranties (Year and Kilometers). The expected warranty cost associated with a second-hand product for 2D-Policies is a function of the age of the item and its usage (as it affects failures over the warranty period), the warranty terms and the servicing strategy used by the dealer. This paper deals with development of models for warranty cost analysis along with the decision on sale price and warranty cover for 2D-Warranty policies associated with sale of second-hand products.

Simulation of 4H-SiC MESFET for High Power and High Frequency Response

Chattopadhyay, S.N.,Pandey, P.,Overton, C.B.,Krishnamoorthy, S.,Leong, S.K. The Institute of Electronics and Information Engin 2008 Journal of semiconductor technology and science Vol.8 No.3

In this paper, we report an analytical modeling and 2-D Synopsys Sentaurus TCAD simulation of ion implanted silicon carbide MESFETs. The model has been developed to obtain the threshold voltage, drain-source current, intrinsic parameters such as, gate capacitance, drain-source resistance and transconductance considering different fabrication parameters such as ion dose, ion energy, ion range and annealing effect parameters. The model is useful in determining the ion implantation fabrication parameters from the optimization of the active implanted channel thickness for different ion doses resulting in the desired pinch off voltage needed for high drain current and high breakdown voltage. The drain current of approximately 10 A obtained from the analytical model agrees well with that of the Synopsys Sentaurus TCAD simulation and the breakdown voltage approximately 85 V obtained from the TCAD simulation agrees well with published experimental results. The gate-to-source capacitance and gate-to-drain capacitance, drain-source resistance and trans-conductance were studied to understand the device frequency response. Cut off and maximum frequencies of approximately 10 GHz and 29 GHz respectively were obtained from Sentaurus TCAD and verified by the Smith's chart.

NONSELECTIVE HARVESTING OF A PREY-PREDATOR COMMUNITY WITH INFECTED PREY

Chattopadhyay, J.,Ghosal, G.,Chaudhuri, K.S. 한국전산응용수학회 1999 Journal of applied mathematics & informatics Vol.6 No.3

The present paper deals with the problem of nonselective harvesting in a partly infected prey and predator system in which both the susceptible prey and the predator follow the law of logistic growth and some preys avoid predation by hiding. The dynamical behaviour of the system has been studied in both the local and global sense. The optimal policy of exploitation has been derived by using Pontraygin's maximal principle. Numerical analysis and computer simulation of the results have been performed to investigate the golbal properties of the system.

Bioprocess Considerations for Production of Secondary Metabolites by Plant Cell Suspension Cultures

Chattopadhyay, Saurabh,Farkya, Sunita,Srivastava, Ashok K.,Bisaria, Virendra The Korean Society for Biotechnology and Bioengine 2002 Biotechnology and Bioprocess Engineering Vol.7 No.3

Plant cell culture provides a viable alternative over whole plant cultivation for the production of secondary metabolites. In order to successfully cultivate the plant cells at large scale, several engineering parameters such as, cell aggregation, mixing, aeration, and shear sensitivity are taken into account for selection of a suitable bioreactor. The media ingredients, their concentrations and the environmental factors are optimized for maximal synthesis of a desired metabolite. Increased productivity in a bioreactor can be achieved by selection of a proper cultivation strategy (batch, fed-batch, two-stage etc.), feeding of metabolic precursors and extraction of intracellular metabolites. Proper understanding and rigorous analysis of these parameters would pave the way towards the successful commercialization of plant cell bioprocesses.

Optically Controlled Silicon MESFET Modeling Considering Diffusion Process

Chattopadhyay, S.N.,Motoyama, N.,Rudra, A.,Sharma, A.,Sriram, S.,Overton, C.B.,Pandey, P. The Institute of Electronics and Information Engin 2007 Journal of semiconductor technology and science Vol.7 No.3

An analytical model is proposed for an optically controlled Metal Semiconductor Field Effect Transistor (MESFET), known as Optical Field Effect Transistor (OPFET) considering the diffusion fabrication process. The electrical parameters such as threshold voltage, drain-source current, gate capacitances and switching response have been determined for the dark and various illuminated conditions. The Photovoltaic effect due to photogenerated carriers under illumination is shown to modulate the channel cross-section, which in turn significantly changes the threshold voltage, drainsource current, the gate capacitances and the device switching speed. The threshold voltage $V_T$ is reduced under optical illumination condition, which leads the device to change the device property from enhancement mode to depletion mode depending on photon impurity flux density. The resulting I-V characteristics show that the drain-source current IDS for different gate-source voltage $V_{gs}$ is significantly increased with optical illumination for photon flux densities of ${\Phi}=10^{15}\;and\;10^{17}/cm^2s$ compared to the dark condition. Further more, the drain-source current as a function of drain-source voltage $V_{DS}$ is evaluated to find the I-V characteristics for various pinch-off voltages $V_P$ for optimization of impurity flux density $Q_{Diff}$ by diffusion process. The resulting I-V characteristics also show that the diffusion process introduces less process-induced damage compared to ion implantation, which suffers from current reduction due to a large number of defects introduced by the ion implantation process. Further the results show significant increase in gate-source capacitance $C_{gs}$ and gate-drain capacitance $C_{gd}$ for optical illuminations, where the photo-induced voltage has a significant role on gate capacitances. The switching time ${\tau}$ of the OPFET device is computed for dark and illumination conditions. The switching time ${\tau}$ is greatly reduced by optical illumination and is also a function of device active layer thickness and corresponding impurity flux density $Q_{Diff}$. Thus it is shown that the diffusion process shows great potential for improvement of optoelectronic devices in quantum efficiency and other performance areas.

Folic acid inhibits necrosis and apoptosis in ischemic and reperfusion induced injury in rat liver

Chattopadhyay, Pronobesh,Shukla, Gunjan,Wahi, Arun Kumar Kyung Hee Oriental Medicine Research Center 2009 Oriental pharmacy and experimental medicine Vol.9 No.1

Temporary clamping of the portal triad is a common strategy to minimize bleeding during liver transplantation. Increasing evidences suggests that oxygen derived free radicals and reintroduction of oxygen in ischemic tissue lead to ischemic and reperfusion injury (I/R) and lead to apoptosis and necrosis. Adult Wistar rat subjected to 60 min of partial liver ischemia followed by three hour reperfusion. Eighteen Wister rats were divided into sham-operated control group (I) (n = 6), ischemia and reperfusion group (II) (n = 6), folic acid treated group (1 mg/kg body weight/daily by oral route for 7 days before induced ischemia reperfusion maneuver) (III) (n = 6). Apoptotic and necrotic hepatocytes, mitochondrial antioxidant enzymes were measured. Liver injury was assessed by alanine transaminases (ALT), aspartate transaminases (AST), liver histopathology and electron microscopy. An ischemic and reperfusion hepatocellular injury was indicated by increased serum-ALT, AST, histopathology and electron microscopy studies. Apoptotic and necrotic cells were increased which was revealed by flow cytometry in I/R group. Pre- treatment with folic acid significantly decreased serum -ALT, AST levels, apoptotic and necrotic cells after 1 h ischemia followed by 3 h of reperfusion. Histopathology and TEM studies showed markedly diminished hepatocellular injury in folic acid pretreated rats during the hepatic I/R, which reached a level comparable to saline-treated rat of sham operated group. On the basis of our findings it may be concluded that folic acid afforded significant protection from necrosis and apoptosis in I/R injury.

Peroxidase Activity during Leaf Infection of Mulberry (Morus alba L.) with Brown Leaf Spot Fungus Myrothecium roridum

Chattopadhyay Soumen,Krishnan Natraj,Maji Manas D. Korean Society of Sericultural Science 2006 International Journal of Industrial Entomology Vol.12 No.1

Peroxidase activity was measured in brown leaf spot pathogen (Myrothecium roridum) inoculated potted mulberry (Morus alba) during pre-symptomatic to various symptom development stages and compared with corresponding healthy leaf tissues. The enzyme showed a pH optimum of 7.0 and the activity was linearly increased up to 15 min of incubation. The peroxidase had a broad substrate specificity and the rates of oxidation were in the rank of pyrogallol> guaiacol> ascorbate at pH 7.0. Catechol at 10 mM inhibited 89% of guaiacol-peroxidase and 76% pyrogallol-peroxidase activities, indicated higher non-specific peroxidation in pyrogallol dependent assay system in mulberry than guaiacol. The optimum requirement for the guaiacol dependent assay was 0.2 ml (${\approx}40-60{\mu}g$ equivalent of protein) of crude enzyme source. Excepting the 8th leaf from the apex, the peroxidase activity did not vary appreciably in different leaf positions. In pre-symptomatic phases, an initial (1 to 5 min) rise of peroxidase activity was noticed in inoculated leaves, and then maintained a plateau up to 300 min. In contrary, non-infected tissue showed a slightly increased trend of enzyme level up to 420 min. In infected tissue, a sharp transient increase (3.1 fold) of peroxidase activity appeared between 300 - 420 min post infections. Afterwards, significantly different but steady maintenance of enzyme levels were observed in two treatments. On the other hand, during symptom development, a sharp increase in peroxidase activity was noticed up to 4th grade of lesion appearance (25.1 % to 50% of leaf area infection), and then declined slightly. However, in non-infected but same age healthy leaves, such huge fluctuations of enzyme level did not apparent. A high positive correlation $(R^2=0.92)$ between peroxidase activity and leaf spot development grades was also marked. The result implies that pre-symptomatic burst (between 1 - 5 and 300 - 420 min) and subsequent increased trend of guaiacol peroxidase activity may require for the symptomatic manifestation of Myrothecium leaf spot in mulberry.