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1.
Indian J Gastroenterol ; 42(2): 279-285, 2023 04.
Article En | MEDLINE | ID: mdl-37162701

Pancytopenia in children with celiac disease (CeD) is postulated to be due to nutritional deficiency such as vitamin B12, folate and copper or an autoimmune process resulting in aplastic anemia with hypoplastic marrow. In the present case series, we report the profile and explore the etiology of pancytopenia among children with CeD. There are only a few case reports of pancytopenia in children with CeD. We enrolled newly diagnosed cases of CeD and pancytopenia presenting in the celiac disease clinic over three years. Detailed evaluation was carried out for the cause of pancytopenia. We followed up on the cases for compliance and response to gluten-free diet at three months, six months and 12 months. Twenty patients were eligible for inclusion. They were divided into two groups: one with aplastic anemia with hypoplastic marrow labeled as Gp CeD-AA and the other with megaloblastic/nutritional anemia labeled as Gp CeD-MA. Patients in Gp CeD-MA presented with classical symptoms of CeD as recurrent diarrhea, abdomen distension, pallor and poor weight gain. They had none or just one transfusion requirement and had an early and complete recovery from pancytopenia. Patients in Gp CeD-AA presented with atypical symptoms such as epistaxis, short stature, fever, pallor and weakness. They had a multiple blood transfusion requirement and had delayed and partial recovery from pancytopenia. Pancytopenia is not a disease in itself but is the presentation of an underlying disease. It can occur due to various coexisting disorders in children with CeD, which can be as simple as nutritional deficiencies to as complex as an autoimmune process or malignancy. CeD should be included in the differential diagnosis of aplastic anemia as CeD and aplastic anemia both have a similar pathological process involving T cell destruction of tissues.


Anemia, Aplastic , Anemia, Megaloblastic , Celiac Disease , Pancytopenia , Humans , Child , Pancytopenia/etiology , Pancytopenia/diagnosis , Pancytopenia/pathology , Anemia, Aplastic/complications , Anemia, Aplastic/diagnosis , Anemia, Aplastic/pathology , Celiac Disease/complications , Celiac Disease/diagnosis , Pallor/complications , Anemia, Megaloblastic/complications
2.
Pediatr Gastroenterol Hepatol Nutr ; 26(1): 50-57, 2023 Jan.
Article En | MEDLINE | ID: mdl-36816433

Purpose: The purpose of this study was to determine the pattern of human leukocyte antigen (HLA)-DQ genotype in children diagnosed with celiac disease (CD) (biopsy proven), and to compare this with a control group; and secondarily, to correlate HLA genotypes with clinical profiles of CD. Methods: This cross-sectional comparative observational study included 26 controls and 52 patients diagnosed with CD who presented at Sir Padampat Mother and Child Health Institute, Jaipur, from May, 2017 to October, 2018. HLA DQ genotype was assessed for each patients and correlated with clinical profiles. Results: HLA DQ2/DQ8 genotypes were significantly more common in CD (present in 100.0% cases) than in controls (23.1%) in Northern India (Rajasthan). When HLA DQ2.5 and DQ8 were present together, individuals had significantly more atypical presentations and severe findings on duodenal biopsy. Similarly, patients with the HLA DQ 2.5 genotype were also predisposed to more severe endoscopic findings, while HLA DQ2.2 predisposed them to less severe biopsy findings. HLA DQ8 was significantly associated with later age at diagnosis (>5 years) and shorter stature. The highest HLA DQ relative risk (RR) for CD development was associated with HLA DQ2.5 and DQ2.2 in combination, followed by HLA DQ2.5 and DQ8 in combination, while HLA DQx.5 and HLA DQ2.2 together had the lowest risk. Conclusion: HLA DQ2/DQ8 genotypes are strongly associated with pediatric CD patients in northern India. These genotypes and their combinations may be associated with different clinical presentations of CD, and may help predict severity of CD.

3.
Appl Opt ; 62(5): 1399-1405, 2023 Feb 10.
Article En | MEDLINE | ID: mdl-36821245

B 4 C-coated thin film mirrors are used in high brilliance synchrotron and x-ray free electron laser beamlines due to their low absorption coefficient and high thermal stability. As in the case of gold, platinum, and other thin film mirrors, B 4 C-coated mirrors also are affected due to synchrotron radiation-induced carbon contaminations in beamlines. In the present study, a graphitic carbon (C) layer deposited on top of boron carbide (B x C) thin film surface is removed by five successive oxygen radio frequency (RF) plasma exposures (RF power, 10 W; O 2 flow, 30 sccm; exposure time, 10 min each). Before and after the carbon layer removal, structural and compositional properties of the B x C/C bilayer are characterized by soft x-ray reflectivity, x-ray photoelectron spectroscopy, grazing angle x-ray diffraction, and Raman spectroscopy techniques. Characterization results reveal that in the first four exposures the carbon layer thickness decreases continuously without affecting the B x C layer properties; however, in the fifth exposure, the carbon layer is completely removed along with a partial etching of the B x C layer too.

4.
ACS Omega ; 7(50): 46466-46474, 2022 Dec 20.
Article En | MEDLINE | ID: mdl-36570223

Nanocomposite zinc oxide nanorods capped with oleic acid (ZOR) with positive dielectric anisotropy liquid crystal (LC) 4'-octyl-4-biphenylcarbonitrile (8CB) filled in unaligned cells exhibit homeotropic alignment of host LC molecules. Further, systematic investigation of the textural, dielectric, and conductivity properties of nanocomposites filled in planar cells is performed with increasing concentration of nanorods. At a nanorod concentration ≤0.2 wt % in 8CB, the order parameter of nanocomposite samples is found to be increasing and ionic conductivity is found to be decreasing as compared to pure LC. Beyond 0.3 wt % concentration of nanorods in 8CB, vertical alignment (VA) of host LC is observed even in a planar aligned cell. The VA of LC molecules in ZOR nanocomposites is confirmed through attenuated total reflection-Fourier transform infrared absorption spectra studies.

5.
JMIR Infodemiology ; 2(1): e31473, 2022.
Article En | MEDLINE | ID: mdl-37113803

Background: Public sentiments are an important indicator of crisis response, with the need to balance exigency without adding to panic or projecting overconfidence. Given the rapid spread of the COVID-19 pandemic, governments have enacted various nationwide measures against the disease with social media platforms providing the previously unparalleled communication space for the global populations. Objective: This research aims to examine and provide a macro-level narrative of the evolution of public sentiments on social media at national levels, by comparing Twitter data from India, Singapore, South Korea, the United Kingdom, and the United States during the current pandemic. Methods: A total of 67,363,091 Twitter posts on COVID-19 from January 28, 2020, to April 28, 2021, were analyzed from the 5 countries with "wuhan," "corona," "nCov," and "covid" as search keywords. Change in sentiments ("very negative," "negative," "neutral or mixed," "positive," "very positive") were compared between countries in connection with disease milestones and public health directives. Results: Country-specific assessments show that negative sentiments were predominant across all 5 countries during the initial period of the global pandemic. However, positive sentiments encompassing hope, resilience, and support arose at differing intensities across the 5 countries, particularly in Asian countries. In the next stage of the pandemic, India, Singapore, and South Korea faced escalating waves of COVID-19 cases, resulting in negative sentiments, but positive sentiments appeared simultaneously. In contrast, although negative sentiments in the United Kingdom and the United States increased substantially after the declaration of a national public emergency, strong parallel positive sentiments were slow to surface. Conclusions: Our findings on sentiments across countries facing similar outbreak concerns suggest potential associations between government response actions both in terms of policy and communications, and public sentiment trends. Overall, a more concerted approach to government crisis communication appears to be associated with more stable and less volatile public sentiments over the evolution of the COVID-19 pandemic.

6.
Indian Pediatr ; 58(2): 123-125, 2021 02 15.
Article En | MEDLINE | ID: mdl-33257599

OBJECTIVE: To study the clinical and laboratory profile and to assess period for viral clearance in COVID 19 children. METHODS: We reviewed hospital records of children (<18 years) admitted from 1 April to 31 May, 2020 at a tertiary-care public hospital and identified those positive for severe acute respiratory syndrome corona virus (SARS-CoV-2) by RT-PCR of respiratory secretions. RESULTS: 81.2% of the 85 children studied were asymptomatic and 3 (8.5%) died. Severe lymphopenia (43.8%), raised C-reactive protein (93.8%), raised erythrocyte sedimentation rate (75%) and high (>500ng/mL) levels of D-dimer (37.5%) were common. Median (IQR) duration of viral shedding was 7 (5-10) days, with range of 2 to 45 days; 96.3% had viral clearance within 14 days. CONCLUSIONS: Majority of children aged <18 years with SARS-CoV-2 infection had viral clearance within 14 days.


COVID-19 , SARS-CoV-2 , Antibodies, Viral/blood , Blood Sedimentation , C-Reactive Protein/analysis , COVID-19/blood , COVID-19/epidemiology , COVID-19/physiopathology , COVID-19/therapy , COVID-19 Testing/methods , COVID-19 Testing/statistics & numerical data , Child , Female , Fibrin Fibrinogen Degradation Products/analysis , Hospitalization/statistics & numerical data , Humans , India/epidemiology , Lymphocyte Count/methods , Male , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology , Virus Shedding
7.
J Synchrotron Radiat ; 27(Pt 6): 1633-1639, 2020 Nov 01.
Article En | MEDLINE | ID: mdl-33147189

Transition elements exhibit strong correlations and configuration interactions between core and valence excited states, which give rise to different excitations inside materials. Nickel exhibits satellite features in its emission and absorption spectra. Effects of such transitions on the optical constants of nickel have not been reported earlier and the available database of Henke et al. does not represent such fine features. In this study, the optical behaviour of ion beam sputter deposited Ni thin film near the L2,3-edge region is investigated using reflection spectroscopy techniques, and distinct signatures of various transitions are observed. The soft X-ray reflectivity measurements in the 500-1500 eV photon energy region are performed using the soft X-ray reflectivity beamline at the Indus-2 synchrotron radiation source. Kramers-Kronig analysis of the measured reflectivity data exhibit features corresponding to spin orbital splitting and satellite transitions in the real and imaginary part of the refractive index (refraction and absorption spectra). Details of fine features observed in the optical spectra are discussed. To the best of our knowledge, this is the first study reporting fine features in the measured optical spectra of Ni near its L2,3-edge region.

8.
J Synchrotron Radiat ; 26(Pt 4): 1152-1160, 2019 Jul 01.
Article En | MEDLINE | ID: mdl-31274439

Deposition of synchrotron-radiation-induced carbon contamination on beamline optics causes their performance to deteriorate, especially near the carbon K edge. The photon flux losses due to carbon contamination have spurred researchers to search for a suitable decontamination technique to restore the optical surface and retain its performance. Several in situ and ex situ refurbishing strategies for beamline optics are still under development to solve this serious issue. In this work, the carbon contamination is removed from a large (340 mm × 60 mm) Au-coated toroidal mirror surface using a capacitively coupled low-pressure RF plasma. Before and after RF plasma cleaning, the mirror was characterized by Raman spectroscopy, soft X-ray reflectivity (SXR) and atomic force microscopy (AFM) techniques. The Raman spectra of the contaminated mirror clearly show the G (1575-1590 cm-1) and D (1362-1380 cm-1) bands of graphitic carbon. The SXR curve of the contaminated mirror shows a clear dip near the critical momentum transfer of carbon, indicating the presence of carbon contamination on the mirror surface. This dip disappears after removal of the contamination layer by RF plasma exposure. A decrease in the intensities of the CO bands is also observed by optical emission spectrometry during plasma exposure. The AFM and SXR results suggest that the root-mean-square (r.m.s.) roughness of the mirror surface does not increase after plasma exposure.


Gold/chemistry , Plasma Gases , Radio Waves , Microscopy, Atomic Force , Optics and Photonics , Spectrum Analysis, Raman/methods , Synchrotrons
9.
J Environ Manage ; 242: 68-80, 2019 Jul 15.
Article En | MEDLINE | ID: mdl-31028953

Oxygen augmented carbon adsorbent has been developed using polyethylene terephthalate (PET) waste by first carbonizing at different temperatures (500-800 °C) and then chemically activating using different ratios of KOH: PET (mass ratio 1 to 4). The textural characterization divulges the effect of activation in terms of the development of the high surface area and micropore volume of 1690 m2 g-1 and 0.78 cm3 g-1 respectively, for the optimum sample (PET-3-700). Elemental analysis of PET-3-700 illustrates the presence of 34.33% oxygen and XPS results confirmed the occurrence of oxygen moieties which enhance the basicity of the adsorbent and promote CO2 capture. The CO2 adsorption capacity of prepared carbons was determined thermogravimetrically under dynamic conditions, at different concentrations of CO2 (6-100%) and temperatures. The maximum CO2 uptake capacity of 2.31 mmol g-1 was exhibited by PET-3-700 at an adsorption temperature of 30 °C under 100% pure CO2 flow. Four adsorption-desorption cycles corroborate almost complete regenerability of the prepared adsorbent. Adsorption kinetics at all adsorption conditions was described best by fractional order kinetic model. Freundlich isotherm fit indicates the surface of adsorbent being heterogeneous and low values of isosteric heat shows physisorption behavior of the process. Negative values of thermodynamic parameters indicate exothermic and feasible nature of adsorption process.


Carbon Dioxide , Polyethylene Terephthalates , Adsorption , Carbon , Kinetics , Porosity , Thermodynamics
10.
Pediatr Gastroenterol Hepatol Nutr ; 21(2): 86-92, 2018 Apr.
Article En | MEDLINE | ID: mdl-29713605

PURPOSE: Celiac disease is a common non-communicable disease with varied presentations. Purpose of this study was to find the duodeno-endoscopic features in celiac disease and to compare duodeno-endoscopic and histological findings between typical and atypical celiac disease in children. METHODS: Hospital based observational study was conducted at Sir Padampat Mother and Child Health Institute, Jaipur from June 2015 to May 2016. Patients were selected and divided in two groups- typical and atypical celiac disease based upon the presenting symptoms. Upper gastrointestinal endoscopy and duodenal biopsy was performed for serology positive patients. Results were analysed using appropriate statistical test of significance. RESULTS: Out of 101 enrolled patients, 47.5% were male. Age ranged from 1 to 18 years. Study showed that 54.5% were typical and 45.5% were atypical. Patients presenting with atypical symptoms were predominantly of older age group. On endoscopy, scalloping, mosaic pattern, reduced fold height and absent fold height; and in histology, advanced Marsh stage were significantly higher in the typical group. CONCLUSION: Awareness of atypical presentations as well as duodeno-endoscopic features may have considerable practical importance for the diagnosis of celiac disease in children. Scalloping, mosaic pattern, reduced fold height and nodularity are main endoscopic markers of celiac disease in children. Endoscopic markers of duodenal mucosa may be important in early diagnosis of celiac disease, in children subjected to endoscopy for atypical presentations or indication other than suspected celiac disease.

11.
Carbohydr Polym ; 195: 613-621, 2018 Sep 01.
Article En | MEDLINE | ID: mdl-29805018

Polymer-ceramic composite membranes were prepared by dip coating technique using 5 wt.% cellulose acetate (CA) solution at different temperatures (15 °C, 25 °C and 40 °C). The effect of pH (2-12) of the polymeric solution on the properties of the membranes was studied using SEM, EDAX, FTIR, gas and liquid permeation. The thickness of the polymeric layer depended on the interaction of CA solution with the surface of ceramic support. Membrane permeability decreased with increase in pH because of decrease in pore size and porosity resulting from strong interaction of the polymer layer with the ceramic support. The porosity and mean pore size of the prepared membranes were found to be 28-60% and 30-47 nm (ultrafiltration range), respectively. The optimized membrane (pH 7) was used for ultrafiltration of oil in water emulsions (100 and 200 mg/L). Oil rejection of 99.61% was obtained for 100 mg/L of oil concentration in water.

12.
Indian J Pediatr ; 84(5): 344-348, 2017 May.
Article En | MEDLINE | ID: mdl-28025773

OBJECTIVES: To study bone mineral density (BMD) and standard serum biochemical indices among newly diagnosed and already diagnosed cases of Celiac Disease (CD) on gluten free diet for at least one year. METHODS: This hospital based analytic, observational study was done at a tertiary care centre, from April 2013 through June 2014. Thirty six children (20 females) with untreated CD at diagnosis (Group A) and 36 age and sex matched children on gluten-free diet for at least one year (Group B) were studied. Serum measurements of biochemical bone health indices and BMD, assessed by dual X-ray absorptiometry, were obtained. RESULTS: BMD Z-score was significantly low in newly diagnosed celiac patients. Patients on gluten free diet had higher BMD Z-score as compared to newly diagnosed patients (-2.02 vs. -0.65 respectively, p < 0.001). BMD Z-score was high in GI symptom patients as compared to non-GI symptom patients (-0.46+/-0.89 vs. - 0.88 = +/-0.94) in Group B. In female patients BMD Z-score was comparatively low as compared to male patients in both groups but difference was not significant. In Group A the mean serum calcium level was lower than the patients in Group B (8.72 + 0.73 vs. 9.34 + 0.65, p < 0.001). S. calcium levels were not correlated with bone mineral density (BMD) in both groups (P value >0.05). CONCLUSIONS: Children with CD are at risk for reduced BMD. Strict gluten-free diet significantly improves bone mineralization. Early diagnosis and treatment of celiac disease during childhood may protect CD patients from osteoporosis.


Bone Density , Celiac Disease/pathology , Absorptiometry, Photon , Adolescent , Case-Control Studies , Celiac Disease/diet therapy , Child , Child, Preschool , Diet, Gluten-Free , Female , Humans , Male
13.
PLoS One ; 11(10): e0162350, 2016.
Article En | MEDLINE | ID: mdl-27755540

Wheat cultivars with wide introgression have strongly impacted global wheat production. Aegilops geniculata (MgUg) is an important wild relative with several useful traits that can be exploited for wheat improvement. Screening of Ae. geniculata addition lines indicated a negative effect of 1Ug and the positive effect of 1Mg chromosome on wheat dough strength. Negative effect of 1Ug is probably associated with variation in number and position of the tripeptide repeat motif in the high molecular weight glutenin (HMW-G) gene. To utilize the positive potential of 1Mg chromosome, three disomic substitution lines (DSLs) 1Mg(1A), 1Mg(1B) and 1Mg(1D) were created. These lines were characterized for morphological, cytogenetic properties and biochemical signatures using FISH, 1D-, 2D-PAGE and RP-HPLC. Contribution of wheat 1A, 1B and 1D chromosomes towards dough mixing and baking parameters, chapatti quality, Fe/Zn content and glume color were identified. Observed order of variation in the dough mixing and baking parameters {1Mg(1D) ≤wheat ≤1Mg(1B) ≤1Mg(1A)} indicated that chromosome specific introgression is desirable for best utilization of wild species' potential.


Chromosomes, Plant/genetics , Triticum/genetics , Bread/analysis , Chromatography, High Pressure Liquid , Chromosomes, Plant/metabolism , Electrophoresis, Gel, Two-Dimensional , Glutens/chemistry , Glutens/genetics , Glutens/metabolism , In Situ Hybridization, Fluorescence , Poaceae/genetics , Rheology , Seed Storage Proteins/genetics , Seed Storage Proteins/metabolism
14.
Physiol Mol Biol Plants ; 21(4): 591-6, 2015 Oct.
Article En | MEDLINE | ID: mdl-26600685

Released and pre-released bread wheat varieties evaluated in national wheat programme of India (503 genotypes) during 2005-14 under different environments were examined for the role of physiological parameters in grain quality. Genotypes with slow plant height growth but faster rate of grain filling enhanced protein content. Plants where growth in height and grain development was slow, grains were hard, provided proportionate vegetative growth phase is longer. Steady grain growth rate benefited gluten strength and gluten quality. Irrespective of total crop duration, longer reproductive phase was an effective indicator of higher flour recovery and test weight. Magnitude and significance of morphological attributes in grain quality was almost similar to that of physiological processes, therefore prospects of utilizing these field traits were examined to enhance grain properties. Early heading and longer grain filling was effective to increase test weight whereas delayed heading and shorter plant height enhanced protein content. Bold grains hampered grain hardness and delayed heading added more bran in the flour. Genotypes with poor grain bearing and quick grain ripening had lower sedimentation value. Instead of protein, it was wet gluten which expressed negative association with yield. To improvise gluten quality, extended reproductive phase but with less grain weight was helpful. Contribution of longer post-anthesis period was observed crucial in flour recovery. These useful simple field expressions can be deployed to uplift quality of wheat grains.

15.
Physiol Mol Biol Plants ; 21(3): 447-51, 2015 Jul.
Article En | MEDLINE | ID: mdl-26261410

High yielding genotypes differing for high molecular weight glutenin subunits at Glu D1 locus in national wheat programme of India were examined for bread loaf volume, gluten and protein contents, gluten strength, gluten index and protein-gluten ratio. Number of superior bread quality genotypes in four agro-climatically diverse zones of Indian plains was comparable in both categories of wheat i.e., 5 + 10 and 2 + 12. There wasn't any difference in average bread loaf volume and grain protein content either. 5 + 10 wheats showed better gluten strength and their gluten quality was also superior in the zones where protein content was high. 2 + 10 wheats exerted more gluten due to better protein-gluten ratio. Good bread making in 5 + 10 was derived by better gluten strength and also gluten quality in certain regions but bread quality in 2 + 12 wheats was channelized through higher gluten content as they were more efficient in extracting gluten from per unit protein. Difference in route to bread quality was apparent as gluten content and gluten strength were the key gluten attributes in 5 + 10 whereas protein content and gluten index were prominent in 2 + 12 types. Unlike 2 + 12, there was a ceiling in gluten harvest of 5 + 10 wheats as higher protein failed to deliver more gluten after some limit.

16.
Appl Opt ; 52(8): 1725-30, 2013 Mar 10.
Article En | MEDLINE | ID: mdl-23478778

An UV cleaning technique has been used for the removal of carbon contamination from grating surface, using oxygen free-radicals generated by the absorption of UV radiation (172 nm) in atmospheric oxygen. The extent of restoration of absolute diffraction efficiency (ADE) and grating blaze angle of a carbon-contaminated variable line-spaced concave grating (average line spacing of 1200 lines/mm, blaze angle 3.2 deg, and blaze wavelength 10 nm) has been studied over a 5-70 nm wavelength range. The contamination (due to prolonged use in extreme-ultraviolet spectrograph) resulted in a drastic reduction in the diffraction efficiency of grating, along with a change in the blaze angle. The UV cleaning led to the restoration of blaze angle as well as to an increase in the ADE by more than an order of magnitude for the first two diffraction orders (i.e., from ~0.2 to ~7.2%) for the first diffraction order and 0.1 to ~5% for the second diffraction order at the blaze wavelength. The study is useful for the restoration of carbon-contaminated costly optics.

17.
J Pak Med Assoc ; 61(4): 381-3, 2011 Apr.
Article En | MEDLINE | ID: mdl-21465978

OBJECTIVE: To evaluate the drug use habit of pregnant women in villages of central India. METHODS: An observational, cross sectional study was conducted among six hundred fifty pregnant women from different randomly selected villages of Wardha district of central India through interviews on medicine use behaviour and evaluation of prescriptions. RESULTS: Pregnant women of younger age group from lower socio economic status constituted the majority of the study population. Major portion (97.7) of this socioeconomically backward population followed the doctor's advice as far as dose, frequency and duration of the drug was concerned. The antenatal mothers were of the opinion that, if the instructions on the drug envelop or foil was in written in the local language, it could be more helpful for them. CONCLUSION: Majority of the study population used drugs or medicines regularly but some mothers were reluctant. This indicated that even in this age of advancement of scientific knowledge, all antenatal mothers were not conversant with the advantages of drug use.


Health Behavior , Prescription Drugs/therapeutic use , Rural Population/statistics & numerical data , Adolescent , Adult , Age Distribution , Cross-Sectional Studies , Female , Humans , India , Interviews as Topic , Pregnancy , Prospective Studies , Risk Factors , Social Class , Socioeconomic Factors , Surveys and Questionnaires , Young Adult
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(3 Pt 1): 032601, 2008 Sep.
Article En | MEDLINE | ID: mdl-18851090

Langmuir films at the air-water interface exhibit a variety of surface phases which arise primarily due to the molecular interaction governed by intermolecular separation. We have studied the thermodynamical aspects of Langmuir monolayers of amphiphilic functionalized gold nanoparticles (AGNs) at the air-water (A-W) interface. Interestingly, the AGN monolayer exhibits phases like gas, a low-ordered liquid (L1) , a high-ordered liquid (L2) , and a collapsed state. We find that the first-order phase transition between L1 and L2 vanishes above a critical temperature of 28.4 degrees C . Surprisingly, for a range of higher temperatures ( > or = 29.4 degrees C and < or = 36.3 degrees C ), the L1 phase undergoes a transition to a bilayer of the L2 phase before entering into the collapsed state.

19.
Anal Chim Acta ; 568(1-2): 109-18, 2006 May 24.
Article En | MEDLINE | ID: mdl-17761250

Octadecanethiol (ODT) is known to form self-assembled monolayer on noble metal surfaces which has potential technological applications. Langmuir-Blodgett (LB) technique is another useful method of obtaining highly ordered assembly of molecules. It is of interest to find whether ODT molecules can also form a stable Langmuir monolayer which facilitates the preparation of LB films. In literature, it has been reported that ODT molecules form an unstable Langmuir monolayer. We have studied the stability of the monolayer of the ODT molecules at air-water interface using surface manometry and microscopy techniques. We find the monolayer to be stable on ultrapure water of resistivity greater than 18MOmega cm. However, the behavior changes in the presence of even small amount of additives like NaOH or CdCl2 in the subphase. Our AFM studies on the LB films of ODT deposited from ion-free ultrapure water showed streak-like bilayer domains. The LB films of ODT deposited from CdCl2 containing aqueous subphase yield dendritic domains of the complexed unit grown over ODT monolayer. These nanostructures on surfaces may have potential applications in molecular electronics.

20.
Funct Integr Genomics ; 5(4): 254-9, 2005 Oct.
Article En | MEDLINE | ID: mdl-15711959

In hexaploid wheat, single-locus and two-locus quantitative trait loci (QTL) analyses for grain protein content (GPC) were conducted using two different mapping populations (PI and PII). Main effect QTLs (M-QTLs), epistatic QTLs (E-QTLs) and QTL x environment interactions (QE, QQE) were detected using two-locus analyses in both the populations. Only a few QTLs were common in both the analyses, and the QTLs and the interactions detected in the two populations differed, suggesting the superiority of two-locus analysis and the need for using several mapping populations for QTL analysis. A sizable proportion of genetic variation for GPC was due to interactions (28.59% and 54.03%), rather than to M-QTL effects (7.24% and 7.22%), which are the only genetic effects often detected in the majority of QTL studies. Even E-QTLs made a marginal contribution to genetic variation (2.68% and 6.04%), thus suggesting that the major part of genetic variation is due to changes in gene networks rather than the presence or absence of specific genes. This is in sharp contrast to the genetic dissection of pre-harvest sprouting tolerance conducted by us earlier, where interaction effects were not substantial, suggesting that the nature of genetic variation also depends on the nature of the trait.


Plant Proteins/metabolism , Polyploidy , Quantitative Trait Loci , Triticum/genetics , Plant Proteins/genetics , Triticum/metabolism
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