44 research outputs found
Culture of Silence: A Case Study of Barriers to Two-Way Communication
Feedback is substantial in communication process. Consequently, due to absence of two-way communication in classroom, teaching and learning are not productive and prolific in most of Indian institutions. Secondly, talk or interaction is a significant medium of students’ assessment and by listening to what they have to say teachers support their learning. Several studies conclude that classroom discussions are often dominated by a small number of students while others remain silent and quiet. The study was precisely conducted to find out the factors or barriers contributing to students’ reluctance to communicate in the classrooms. The case study method was employed and total 35-student was interviewed. The study concludes that dialogue or communication between teachers and students is a vital part of the education process and those students who do not speak in the classrooms are disadvantaged. The study found that psychological, emotional, practical, social attitude and previous school education barriers was the salient that responsible to students communication behavior in the classrooms. These barriers must be removed to ensure the participation of quiet students to make active role in education. Keywords: Communication, Barriers, classroom, students, teachers etc
Impacts of Scary Television Programmes on children Psychology, Attitude and Behavior
The television programmes influence the perception, behavior and attitude of children negatively and positively. This study was conducted in the District Headquarter town in Dharamshala. The data was collected through circulating both Hindi and English questionnaires to the 100 children during their shopping, playing, and their free time hours at different places. The sample for this study was chosen randomly. The study finds out that scary television programmes have a negative impact on the children behavior, psychology and their attitudes specifically who watch more television than other children. The impact of these television scary programmes remains more than three months on children mind. The fear of unknown and darkness dominate their manner of study. Key Words: Scary, Psychology, attitude, horror, Television, Movies
Rainfall Variability Analysis In The Nira River Basin Using Multi-Model GCM Ensemble
Observed daily rainfall data during baseline period i.e. 1961-1990 of four raingauge stations namely Akluj, Baramati, Bhor and Malsiras located in the Nira River basin in Central India were analyzed to study the impact of climate change on rainfall. LARS-WG incorporating 15 GCM’s from the CMIP3 predictions for A1B, A2 and B1 emission scenarios was used to statistically downscale the daily rainfall data during three time spans centred at 2020’s, 2055’s and 2090’s. Uncertainty in GCMs rainfall predictions was analyzed on monthly, seasonal and annual scales. Kolmogorov-Smirnov test, Student’s t-test, and Fisher test have shown average to good performance during synthetic rainfall data generation for all the stations. The analysis of the data shows that the uncertainty in the prediction increases with the timescale. Also, the variability in the predictions is smaller in annual values followed by seasonal and monthly values. Maximum uncertainty is observed in A2 scenario followed by A1B and B1 Scenarios. Monsoon months show minimum uncertainty in all the scenarios. The rainfall of Dec, Mar, Apr and May months are expected to increase in first two spans while expected to decrease in the last time span 2080 -2099 under all the scenarios. The monsoon month’s rainfall is expected to increase slightly in future for all the scenarios. Baramati shows maximum increase in annual rainfall for all scenarios while rainfall at Malsiras is expected to decrease only during third time span for all three scenarios
Simulation Of Shoreline Changes Along Muthalapozhy Harbour, India
A study of Muthalapozhy fishing harbour, located in south India, was conducted for simulating shoreline changes using LITPACK modelling tool. The analysis shows that the estimated advancement in shoreline is of the order of 45 m/year initially, which gradually reduces to 25 m/year. It was also found that the coastline advances more during the south-west monsoon (i.e. June to September) season. Simulation of breakwaters shows that the length of the breakwater should be increased by 200 m for south breakwater and 70 m for north breakwater to keep the channel operational without dredging till 2016. The results of the simulated shoreline will help the port managers for maintaining the channel round the year
Snowmelt Modelling Of Dhauliganga River Using Snowmelt Runoff Model
Snowmelt modeling was attempted in this study using Snowmelt Runoff Model to simulate streamflow in Tamak Lata Catchment located in the Indian Himalayas. The daily snow cover data was generated using the depletion curves prepared using snow cover information obtained from MODIS remote sensing images during May 2009 to August 2012. Discharge, temperature and rainfall data observed at Tamak Lata during May 2009 to August 2012 were used for calibration and validation of the model. The characteristics of snow cover in the basin shows that the accumulation of snow at higher altitude starts from the second week of October and the snowline comes down to lower elevation up to lower zone. By the end of March, the snowmelt begins and the snowline recedes up to elevation of 5200 m by the end of the melt season. Till the start of the melt season, more than 75% of the basin area is covered with snow and it reduces to approximately 25% at the end of the melt season. The calibration of the model in terms of stream flow has indicated that the low flows and the peaks in the stream flow are well produced. Statistical evaluation of the model performance during calibration period, in the form of efficiency varied from 0.74 to 0.90 with an average value of 0.812 indicating a good model fit. The model performance during validation period was also found to be very good with efficiency with 0.8. The modeling of the snowmelt shows that snow and glacier runoff contribution in Tamak Lata catchment were 63.81% on annual basis and 65.34%, 52.64%, 73.4% for monsoon, post monsoon and, winter and pre-monsoon seasons
Honokiol Arrests Cell Cycle, Induces Apoptosis, and Potentiates the Cytotoxic Effect of Gemcitabine in Human Pancreatic Cancer Cells
Survival rates for patients with pancreatic cancer are extremely poor due to its asymptomatic progression to advanced and metastatic stage for which current therapies remain largely ineffective. Therefore, novel therapeutic agents and treatment approaches are desired to improve the clinical outcome. In this study, we determined the effects of honokiol, a biologically active constituent of oriental medicinal herb Magnolia officinalis/grandiflora, on two pancreatic cancer cell lines, MiaPaCa and Panc1, alone and in combination with the standard chemotherapeutic drug, gemcitabine. Honokiol exerted growth inhibitory effects on both the pancreatic cancer cell lines by causing cell cycle arrest at G1 phase and induction of apoptosis. At the molecular level, honokiol markedly decreased the expression of cyclins (D1 and E) and cyclin-dependent kinases (Cdk2 and Cdk4), and caused an increase in Cdk inhibitors, p21 and p27. Furthermore, honokiol treatment led to augmentation of Bax/Bcl-2 and Bax/Bcl-xL ratios to favor apoptosis in pancreatic cancer cells. These changes were accompanied by enhanced cytoplasmic accumulation of NF-κB with a concomitant decrease in nuclear fraction and reduced transcriptional activity of NF-κB responsive promoter. This was associated with decreased phosphorylation of inhibitor of kappa B alpha (IκB-α) causing its stabilization and thus increased cellular levels. Importantly, honokiol also potentiated the cytotoxic effects of gemcitabine, in part, by restricting the gemcitabine-induced nuclear accumulation of NF-κB in the treated pancreatic cancer cell lines. Altogether, these findings demonstrate, for the first time, the growth inhibitory effects of honokiol in pancreatic cancer and indicate its potential usefulness as a novel natural agent in prevention and therapy
Monoclonal Antibodies Recognizing the Non-Tandem Repeat Regions of the Human Mucin MUC4 in Pancreatic Cancer
The MUC4 mucin is a high molecular weight, membrane-bound, and highly glycosylated protein. It is a multi-domain protein that is putatively cleaved into a large mucin-like subunit (MUC4α) and a C-terminal growth-factor like subunit (MUC4β). MUC4 plays critical roles in physiological and pathological conditions and is aberrantly overexpressed in several cancers, including those of the pancreas, cervix, breast and lung. It is also a potential biomarker for the diagnosis, prognosis and progression of several malignancies. Further, MUC4 plays diverse functional roles in cancer initiation and progression as evident from its involvement in oncogenic transformation, proliferation, inhibition of apoptosis, motility and invasion, and resistance to chemotherapy in human cancer cells. We have previously generated a monoclonal antibody 8G7, which is directed against the TR region of MUC4, and has been extensively used to study the expression of MUC4 in several malignancies. Here, we describe the generation of anti-MUC4 antibodies directed against the non-TR regions of MUC4. Recombinant glutathione-S-transferase (GST)-fused MUC4α fragments, both upstream (MUC4α-N-Ter) and downstream (MUC4α-C-Ter) of the TR domain, were used as immunogens to immunize BALB/c mice. Following cell fusion, hybridomas were screened using the aforementioned recombinant proteins ad lysates from human pancreatic cell lines. Three anti MUC4α-N-Ter and one anti-MUC4α-C-Ter antibodies were characterized by several inmmunoassays including enzyme-linked immunosorbent assay (ELISA), immunoblotting, immunofluorescene, flow cytometry and immunoprecipitation using MUC4 expressing human pancreatic cancer cell lines. The antibodies also reacted with the MUC4 in human pancreatic tumor sections in immunohistochemical analysis. The new domain-specific anti-MUC4 antibodies will serve as important reagents to study the structure-function relationship of MUC4 domains and for the development of MUC4-based diagnostics and therapeutics
Activation of JNK Signaling Mediates Amyloid-ß-Dependent Cell Death
Alzheimer's disease (AD) is an age related progressive neurodegenerative disorder. One of the reasons for Alzheimer's neuropathology is the generation of large aggregates of Aß42 that are toxic in nature and induce oxidative stress, aberrant signaling and many other cellular alterations that trigger neuronal cell death. However, the exact mechanisms leading to cell death are not clearly understood.We employed a Drosophila eye model of AD to study how Aß42 causes cell death. Misexpression of higher levels of Aß42 in the differentiating photoreceptors of fly retina rapidly induced aberrant cellular phenotypes and cell death. We found that blocking caspase-dependent cell death initially blocked cell death but did not lead to a significant rescue in the adult eye. However, blocking the levels of c-Jun NH(2)-terminal kinase (JNK) signaling pathway significantly rescued the neurodegeneration phenotype of Aß42 misexpression both in eye imaginal disc as well as the adult eye. Misexpression of Aß42 induced transcriptional upregulation of puckered (puc), a downstream target and functional read out of JNK signaling. Moreover, a three-fold increase in phospho-Jun (activated Jun) protein levels was seen in Aß42 retina as compared to the wild-type retina. When we blocked both caspases and JNK signaling simultaneously in the fly retina, the rescue of the neurodegenerative phenotype is comparable to that caused by blocking JNK signaling pathway alone.Our data suggests that (i) accumulation of Aß42 plaques induces JNK signaling in neurons and (ii) induction of JNK contributes to Aß42 mediated cell death. Therefore, inappropriate JNK activation may indeed be relevant to the AD neuropathology, thus making JNK a key target for AD therapies
Asiatic Acid Inhibits Pro-Angiogenic Effects of VEGF and Human Gliomas in Endothelial Cell Culture Models
Malignant gliomas are one of the most devastating and incurable tumors. Sustained excessive angiogenesis by glioma cells is the major reason for their uncontrolled growth and resistance toward conventional therapies resulting in high mortality. Therefore, targeting angiogenesis should be a logical strategy to prevent or control glioma cell growth. Earlier studies have shown that Asiatic Acid (AsA), a pentacyclic triterpenoid, is effective against glioma and other cancer cells; however, its efficacy against angiogenesis remains unknown. In the present study, we examined the anti-angiogenic efficacy of AsA using human umbilical vein endothelial cells (HUVEC) and human brain microvascular endothelial cells (HBMEC). Our results showed that AsA (5–20 µM) inhibits HUVEC growth and induces apoptotic cell death by activating caspases (3 and 9) and modulating the expression of apoptosis regulators Bad, survivin and pAkt-ser473. Further, AsA showed a dose-dependent inhibition of HUVEC migration, invasion and capillary tube formation, and disintegrated preformed capillary network. AsA also inhibited the VEGF-stimulated growth and capillary tube formation by HUVEC and HBMEC. Next, we analyzed the angiogenic potential of conditioned media collected from human glioma LN18 and U87-MG cells treated with either DMSO (control conditioned media, CCM) or AsA 20 µM (AsA20 conditioned media, AsA20CM). CCM from glioma cells significantly enhanced the capillary tube formation in both HUVEC and HBMEC, while capillary tube formation in both endothelial cell lines was greatly compromised in the presence of AsA20CM. Consistent with these results, VEGF expression was lesser in AsA20CM compared to CCM, and indeed AsA strongly inhibited VEGF level (both cellular and secreted) in glioma cells. AsA also showed dose-dependent anti-angiogenic efficacy in Matrigel plug assay, and inhibited the glioma cells potential to attract HUVEC/HBMEC. Overall, the present study clearly showed the strong anti-angiogenic potential of AsA and suggests its usefulness against malignant gliomas
Withaferin a-induced apoptosis in human breast cancer cells is mediated by reactive oxygen species
Withaferin A (WA), a promising anticancer constituent of Ayurvedic medicinal plant Withania somnifera, inhibits growth of MDA-MB-231 and MCF-7 human breast cancer cells in culture and MDA-MB-231 xenografts in vivo in association with apoptosis induction, but the mechanism of cell death is not fully understood. We now demonstrate, for the first time, that WA-induced apoptosis is mediated by reactive oxygen species (ROS) production due to inhibition of mitochondrial respiration. WA treatment caused ROS production in MDA-MB-231 and MCF-7 cells, but not in a normal human mammary epithelial cell line (HMEC). The HMEC was also resistant to WA-induced apoptosis. WA-mediated ROS production as well as apoptotic histone-associated DNA fragment release into the cytosol was significantly attenuated by ectopic expression of Cu,Zn-superoxide dismutase in both MDA-MB-231 and MCF-7 cells. ROS production resulting from WA exposure was accompanied by inhibition of oxidative phosphorylation and inhibition of complex III activity. Mitochondrial DNA-deficient Rho-0 variants of MDA-MB-231 and MCF-7 cells were resistant to WA-induced ROS production, collapse of mitochondrial membrane potential, and apoptosis compared with respective wild-type cells. WA treatment resulted in activation of Bax and Bak in MDA-MB-231 and MCF-7 cells, and SV40 immortalized embryonic fibroblasts derived from Bax and Bak double knockout mouse were significantly more resistant to WA-induced apoptosis compared with fibroblasts derived from wild-type mouse. In conclusion, the present study provides novel insight into the molecular circuitry of WA-induced apoptosis involving ROS production and activation of Bax/Bak. © 2011 Hahm et al