Identifying Attrition Phases in Survey Data: Applicability and Assessment Study

Background: Although Web-based questionnaires are an efficient, increasingly popular mode of data collection, their utility is often challenged by high participant dropout. Researchers can gain insight into potential causes of high participant dropout by analyzing the dropout patterns. Objective: This study proposed the application of and assessed the use of user-specified and existing hypothesis testing methods in a novel setting—survey dropout data—to identify phases of higher or lower survey dropout. Methods: First, we proposed the application of user-specified thresholds to identify abrupt differences in the dropout rate. Second, we proposed the application of 2 existing hypothesis testing methods to detect significant differences in participant dropout. We assessed these methods through a simulation study and through application to a case study, featuring a questionnaire addressing decision-making surrounding cancer screening. Results: The user-specified method set to a low threshold performed best at accurately detecting phases of high attrition in both the simulation study and test case application, although all proposed methods were too sensitive. Conclusions: The user-specified method set to a low threshold correctly identified the attrition phases. Hypothesis testing methods, although sensitive at times, were unable to accurately identify the attrition phases. These results strengthen the case for further development of and research surrounding the science of attrition

Amino acid changes in the repressor of bacteriophage lambda due to temperature-sensitive mutations in its cI gene and the structure of a highly temperature-sensitive mutant repressor

The mutant cIts genes from seven different λcIts phages carrying tsU50, tsU9, tsU46, ts1, tsU51, tsI-22 and ts2 mutations were cloned in plasmid. The positions of these mutations and the resulting changes of amino acids in the repressor were determined by DNA sequencing. The first four mutations mapping in the N-terminal domain show the following changes: I21S, G53S, A62T and V73A, respectively. Of the three remaining mutations mapping in the C-terminal domain, cItsI-22 and cIts2 show N207T and K224E substitutions respectively, while the mutant cItsU51 gene carries F141I and P153L substitutions. Among these ts repressors, CIts2 having the charge-reversal change K224E was overexpressed from tac promoter in a plasmid and purified, and its structure and function were studied. Operator-binding studies suggest that the ts2 repressor is somewhat defective in monomer-dimer equilibrium and/ or cooperativity even at permissive temperatures and loses its operator-binding ability very rapidly above 25°C. Comparative studies of fluorescence and CD spectra, sulfhydryl group reactivity and elution behaviour in size-exclusion HPLC of both wild-type and ts2-mutant repressors at permissive and non-permissive temperatures suggest that the C-terminal domain of the ts2 repressor carrying a K224E substitution has a structure that does not favor tetramer formation at non-permissive temperatures

Biochemical composition of some catfishes from a coastal river of Bangladesh in relation to a biometric indicator

The proximate contents (protein, lipid, ash, and moisture) of three catfish species (Pangasius pangasius, Clupisoma garua, and Silonia silondia) were investigated from a coastal river of Bangladesh. The proximate composition was determined using the AOAC (1990) standard procedure. The average length and weight of the fish samples used in the experiment were 21.50 ± 1.61 cm and 65.55 ± 13.12 g; 19.67 ± 0.21 cm and 50.74 ± 3.13 g; 18.2 ± 1.21 cm and 43.40 ± 10.42 g for P. pangasius, C. garua, and S. silondia, respectively. The P. pangasius, C. garua, and S. silondia were rich protein sources, with 20.19%, 18.86%, and 15.24%, respectively. On the other hand, the lipid and ash contents were ranged between 2.11% to 3.07% and 0.52% to 2.28% respectively. The present study disclused water as the most abundant element in fish bodies  ranging from 75.05% (P. pangasius) to 79.60% (S. silondia). In log-transformed data, the weight of the fish body had a very significant positive relationship with most of the studied body constituents. In all three fish species, total length in log-transformed data and Fulton's condition factor showed a highly significant positive relationship with most of the studied body constituents. These findings suggest that biological differences like length and weight across species can influence the fishes biochemical composition that should be established

Multiphasic denaturation of the λ repressor by urea and its implications for the repressor structure

Urea denaturation of the λ repressor has been studied by fluorescence and circular dichroic spectroscopies. Three phases of denaturation could be detected which we have assigned to part of the C-terminal domain, N-terminal domain and subunit dissociation coupled with further denaturation of the rest of the C-terminal domain at increasing urea concentrations. Acrylamide quenching suggests that at least one of the three tryptophan residues of the λ repressor is in a different environment and its emission maximum is considerably blue-shifted. The transition in low urea concentration (midpoint approximately 2 M) affects the environment of this tryptophan residue, which is located in the C-terminal domain. Removal of the hinge and the N-terminal domain shifts this transition towards even lower urea concentrations, indicating the presence of interaction between hinge on N-terminal and C-terminal domains in the intact repressor

Anti-Allergic Compounds from Red Tomato Peel

Daily food habit with anti-allergic activities is expected to prevent the onset of allergic diseases and ameliorate allergic symptoms. The red color of ripe tomato fruit is due mainly to the accumulation of the carotenoid all-trans-lycopene, which is produced during fruit ripening. Red tomato peel extract (RTPE) contain lycopene (450mg/ kg) and has been found to have anti-allergic effects on man compare its flesh extract and yellow tomato peel extract (YTPE). RTPE could possibly inhibit histamine release and relieve the symptoms of all types of allergy including cedar pollinosis. To evaluate the anti-allergic effect of RTPE, we performed a research study randomized, on three groups in 50 perennial allergy patients with red peel extract; yellow peel extract; tomato flesh and Dextrin (20 healthy university students as control). All patients using oral administration of red tomato peel extract (RTPE); yellow/pink tomato peel extract (YTPE) and tomato flesh extract (TFE) 30mg per day /patient each group and Dextrin as control (30mg per day /patient each group) for 56 days. We found that the skin test for allergy score significantly decreased in the RTPE group only at the end of the trial compared to the beginning and treated with YTPE and TFE groups. Besides this, we also found that sneezing score decreases significantly at the end of experiment time compare to the beginning (p<0.03). There were decreasing tendencies of rhinorrhea and nasal obstruction in the RTPE group. The patients quality of life was significantly improved in the RTPE group after 56 days of treatment (p=0.02) but not in YTPE; tomato flesh extract (TFE) and dextrin group. A significant improvement in total symptom scores, combining sneezing, rhinorrhea and nasal obstruction, was observed after oral administration of RTPE for 56 days (p=0.01). Thus, this evidence will be helpful for the development of low molecular compounds for allergic diseases and it is expected that a dietary menu including an appropriate intake of carotenoids (fruits & vegetables) may provide a form of complementary and alternative medicine and a preventative strategy for allergic diseases

Inhibition of nucleoporin member Nup214 expression by miR-133b perturbs mitotic timing and leads to cell death

Background: Nucleoporins mediate nucleocytoplasmic exchange of macromolecules and several have been assigned active mitotic functions. Nucleoporins can participate in various mitotic functions like spindle assembly, kinetochore organisation and chromosome segregation- important for genome integrity. Pathways to genome integrity are frequently deregulated in cancer and many are regulated in part by microRNAs. Indeed, altered levels of numerous microRNAs have frequently been associated with tumorigenesis. Here, we unveil a microRNA-mediated regulation of the nucleoporin Nup214 and its downstream effect on genome integrity. Methods: Databases/bioinformatic tools such as miRBase, Oncomine and RNAhybrid predicted Nup214 as a miR-133b target. To validate this, we used luciferase reporter assays, Real-Time PCR and immuno-blotting. Flow cytometry and immuno-blots of mitotic markers were used to analyse cell cycle pattern upon thymidine synchronization and miR-133b treatment. Mitotic indices and chromosomal abnormalities were assessed by immuno-fluorescence for FITC-tagged phospho-H3 as well as video-microscopy for GFP-tagged histone H4. Annexin V/propidium iodide staining, caspase3/ PARP cleavage and colony formation assays were done to investigate cell death upon either miR-133b transfection or NUP214 knockdown by siRNA. UPCI:SCC084, HCT116, HeLa-H4-pEGFP and HEK293 (human oral squamous cell carcinoma, colorectal, cervical carcinomas and embryonic kidney cell lines, respectively) were used. miR-133b and NUP214 expressions were validated in cancer cell lines and tissues by Real-Time PCR. Results: Examination of head and neck tumour tissues and cancer cell lines revealed that Nup214 and miR-133b expressions are negatively correlated. In vitro, Nup214 was significantly downregulated by ectopic miR-133b. This downregulation elevated mitotic indices and delayed degradation of mitotic marker proteins cyclinB1 and cyclinA and dephosphorylation of H3. Moreover, this mitotic delay enhanced chromosomal abnormalities and apoptosis. Conclusions: We have identified NUP214, a member of the massive nuclear pore complex, as a novel miR-133b target. Thus, we have shown a hitherto unknown microRNA regulation of mitosis mediated by a member of the nucleoporin family. Based on observations, we also raise some hypotheses regarding transport-dependent/independent functions of Nup214 in this study. Our results hence attempt to explain why miR-133b is generally downregulated in tumours and lay out the potential for Nup214 as a therapeutic target in the treatment of cancer

Chemically deposited magnesium hydroxide thin film

Here we report for the first time to the best of our knowledge the processing techniques, nucleation kinetics and the nanoindentation behaviour of a 1.5 mu m magnesium hydroxide thin film chemically deposited on a commercially available soda lime silica glass substrate at room temperature. The phase and microstructure of the films were analysed by X-ray diffraction, scanning electron microscopy, field emission scanning electron microscopy as well as transmission electron microscopy. An exponential nucleation kinetics was identified for the growth of the thin films. The nanomechanical properties, e. g. nanohardness and Young's modulus of the films were measured by the nanoindentation technique at ultralow loads of 50, 70 and 100 mu N. Finally, the nature of deformation of the thin film was analysed in terms of the energetics of the nanoindentation process and the microstructure

Reduction of Allergenicity of Litchi chinensis Flowers Pollen Protein Conjugated with Polysaccharide by Maillard Reaction

Background: Allergy to pollen from gymnosperms is well documented in the west. The objective was to define the allergologic protein from Litchi chinensis (Litchi) pollen and conjugate the protein with polysaccharides by Maillard reaction to reduce the allergic effect of that protein. Methods: Total soluble proteins were extracted from the pollen of Litchi flower pollen and subjected to ammonium sulphate precipitation at 80% saturation. Pollen antigen from Litchi chinensis (Litchi) was prepared by gel cutting method and characterized by biochemical and designated by LFPP. The homogeneity of this protein was demonstrated by a single band on SDS-PAGE. The protein then conjugated with galactomannan through Maillard Reaction. The resulting purified pollen protein and conjugated protein were administered to the Swiss albino mice as amount of 5.8mg/kg body weight. Results: The total protein was then separated on a 12% SDS-Polyacrylamide gel which revealed 5 bands between molecular weight range of 29kDa and 69kDa. Each band was recovered from the gel by electroelution and sent for skin tests. 28kDa proteins was the only allergenic protein while others were not shown reactivity in patients. Intraperitoneal injection of the purified protein (LFPP) caused a significant rise in the levels of neutrophils (38-81%) and eosinophils (3-14%) compared to control (P&lt;0.001) whereas conjugated protein caused only a 2% increase of both neutrophils and eosinophils level. On the other hand treatment with LFPP-galactomannan conjugate causes no such change in physical appearance with eosinophils and neutrophils level. Conclusion: The present study demonstrates that the protein extracted and purified from Litchi flowers pollen has been recognized as a new allergen from Bangladesh for the first time and the allergic effects can be reduced by conjugation with polysaccharides

"The fruits of independence": Satyajit Ray, Indian nationhood and the spectre of empire

Challenging the longstanding consensus that Satyajit Ray's work is largely free of ideological concerns and notable only for its humanistic richness, this article shows with reference to representations of British colonialism and Indian nationhood that Ray's films and stories are marked deeply and consistently by a distinctively Bengali variety of liberalism. Drawn from an ongoing biographical project, it commences with an overview of the nationalist milieu in which Ray grew up and emphasizes the preoccupation with colonialism and nationalism that marked his earliest unfilmed scripts. It then shows with case studies of Kanchanjangha (1962), Charulata (1964), First Class Kamra (First-Class Compartment, 1981), Pratidwandi (The Adversary, 1970), Shatranj ke Khilari (The Chess Players, 1977), Agantuk (The Stranger, 1991) and Robertsoner Ruby (Robertson's Ruby, 1992) how Ray's mature work continued to combine a strongly anti-colonial viewpoint with a shifting perspective on Indian nationhood and an unequivocal commitment to cultural cosmopolitanism. Analysing how Ray articulated his ideological positions through the quintessentially liberal device of complexly staged debates that were apparently free, but in fact closed by the scenarist/director on ideologically specific notes, this article concludes that Ray's reputation as an all-forgiving, ‘everybody-has-his-reasons’ humanist is based on simplistic or even tendentious readings of his work