425 research outputs found
Toxicological profile for hexachlorobutadiene
No full textATSDR/TP-93/08Chemical manager(s)/author(s): Gangadhar Choudhary, Joyce M. Donohue, Yvonne N. Hales.Prepared by Life Systems, Inc., under subcontract to Clement International Corporation;prepared for U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry under contract no. 205-88-0608.Includes bibliographical references (p. 105-128).205-88-060
Author response: Multiple short windows of calcium-dependent protein kinase 4 activity coordinate distinct cell cycle events during Plasmodium gametogenesis
No full textMalaria transmission relies on the production of gametes following ingestion by a mosquito. Here, we show that Ca2+-dependent protein kinase 4 controls three processes essential to progress from a single haploid microgametocyte to the release of eight flagellated microgametes in Plasmodium berghei. A myristoylated isoform is activated by Ca2+ to initiate a first genome replication within twenty seconds of activation. This role is mediated by a protein of the SAPS-domain family involved in S-phase entry. At the same time, CDPK4 is required for the assembly of the subsequent mitotic spindle and to phosphorylate a microtubule-associated protein important for mitotic spindle formation. Finally, a non-myristoylated isoform is essential to complete cytokinesis by activating motility of the male flagellum. This role has been linked to phosphorylation of an uncharacterised flagellar protein. Altogether, this study reveals how a kinase integrates and transduces multiple signals to control key cell-cycle transitions during Plasmodium gametogenesis.</jats:p
Microbial transformation of nandrolone with Cunninghamella echinulata and Cunninghamella blakesleeana and evaluation of leishmaniacidal activity of transformed products
No full textTherapeutic potential of nandrolone and its derivatives against leishmaniasis has been studied. A number of derivatives of nandrolone (1) were synthesized through biotransformation. Microbial transformation of nandrolone (1) with Cunninghamella echinulata and Cunninghamella blakesleeana yielded three new metabolites, 10β,12β,17β-trihydroxy-19-nor-4-androsten-3-one (2), 10β,16α,17β-trihydroxy-19-nor-4-androsten-3-one (3), and 6β,10β,17β-trihydroxy-19-nor-4-androsten-3-one (4), along with four known metabolites, 10β,17β-dihydroxy-19-nor-4-androsten-3-one (5), 6β,17β-dihydroxy-19-nor-4-androsten-3-one (6) 10β-hydroxy-19-nor-4-androsten-3,17-dione (7) and 16β,17β- dihydroxy-19-nor-4-androsten-3-one (8). Compounds 1-8 were evaluated for their anti-leishmanial activity. Compounds 1 and 8 showed a significant activity in vitro against Leishmania major. The leishmanicidal potential of compounds 1-8 (IC50 = 32.0 ± 0.5, andgt;100, 77.39 ± 5.52, 70.90 ± 1.16, 54.94 ± 1.01, 80.23 ± 3.39, 61.12 ± 1.39 and 29.55 ± 1.14 μM, respectively) can form the basis for the development of effective therapies against the protozoal tropical disease leishmaniasis. © 2014 Elsevier Inc. All rights reserved.Al-Aboudi A, 2009, STEROIDS, V74, P483, DOI 10.1016-j.steroids.2009.01.002; Alarcon J, 2007, J MOL CATAL B-ENZYM, V48, P23, DOI 10.1016-j.molcatb.2007.06.001; Antinarelli Luciana Mr, 2012, Org Med Chem Lett, V2, P16, DOI 10.1186-2191-2858-2-16; Borges KB, 2008, J PHARMACEUT BIOMED, V46, P945, DOI 10.1016-j.jpba.2007.05.018; Borges KB, 2009, TETRAHEDRON-ASYMMETR, V20, P385, DOI 10.1016-j.tetasy.2009.02.009; BORIS A, 1967, STEROIDS, V9, P299, DOI 10.1016-0039-128X(67)90114-6; CASPI E, 1989, J CHEM SOC CHEM COMM, P1699, DOI 10.1039-c39890001699; Choudhary MI, 2010, STEROIDS, V75, P956, DOI 10.1016-j.steroids.2010.05.017; Choudhary MI, 2008, NAT PROD RES, V22, P1289, DOI 10.1080-14786410500462660; Choudhary MI, 2005, CHEM BIODIVERS, V2, P392, DOI 10.1002-cbdv.200590019; Choudhary MI, 2011, STEROIDS, V76, P1288, DOI 10.1016-j.steroids.2011.06.007; Choudhary MI, 2009, STEROIDS, V74, P1040, DOI 10.1016-j.steroids.2009.08.003; Choudhary MI, 2007, STEROIDS, V72, P923, DOI 10.1016-j.steroids.2007.08.002; Choudhary MI, 2012, J ENZYM INHIB MED CH, V27, P348, DOI 10.3109-14756366.2011.590804; de Flines J, 1963, RECL TRAV CHIM PAY B, V82, P129; de Flines J, 1963, RECL TRAV CHIM PAY B, V82, P121; de Flines J, 1963, RECL TRAV CHIM PAY B, V82, P149; Desjeux P, 2004, COMP IMMUNOL MICROB, V27, P305, DOI 10.1016-j.cimid.2004.03.004; Farooq A, 2002, Z NATURFORSCH C, V57, P303; Hazra S, 2013, EXP PARASITOL, V135, P407, DOI 10.1016-j.exppara.2013.07.021; Hernandez-Torres A, 2013, SCAND J INFECT DIS, V45, P567, DOI 10.3109-00365548.2012.752859; Huszcza E, 2003, J BASIC MICROB, V43, P113, DOI 10.1002-jobm.200390011; Kolet SP, 2013, STEROIDS, V78, P1152, DOI 10.1016-j.steroids.2013.08.004; Kouvelas D, 2008, INT J NEUROPSYCHOPH, V11, P925, DOI 10.1017-S1461145708008754; Oliveira-Silva FD, 2008, AM J TROP MED HYG, V78, P745; Parshikov IA, 2000, APPL ENVIRON MICROB, V66, P2664, DOI 10.1128-AEM.66.6.2664-2667.2000; Shao-rui C, 2010, CHEM RES CHINESE U, V26, P922; Yazdi MT, 2006, ARCH PHARM, V339, P473, DOI 10.1002-ardp.2005002350
Estimation of Distribution of Income in Pakistan, Using Micro Data
No full textIncome distribution entered the post war discussion of economic development fairly late. Until the 1960s much of the focus was on industrialisation and the need for capital accumulation. Pakistan was no exception as in the early 60s economic expansion became the main target and means to political identity. Rapid population growth associated with steep decline in mortality demanded acceleration of production to keep pace. Overall aggregate expansion was much faster than before but without benefit for the poor. In that context emerged a new professional interest in income distribution. Haq’s (1964) study was one of the oldest studies conducted to measure inequality in personal income distribution in the high income brackets in the urban areas of Pakistan. The main objective of the author was to present the income distribution pattern in terms of the relative shares of different income groups as well as in terms of Pareto coefficients and concentration ratio during the period 1948-49 to 1957-58 for which published tax data was available. While recognising the limitations of the data used, the author went on to calculate various measures of income inequality including Pareto coefficient and Lorenz curve. The author also made comparison of Pakistan’s income distribution with U.S.A. and U.K.
Machine learning predicted magnetic entropy change using chemical descriptors across a large compositional landscape
No full textMagnetocaloric refrigeration has drawn considerable attention in the last few decades as it can positively disrupt the current cooling technology. Most research efforts focus on developing new magnetic materials in the laboratory by trial and error. Here we report a materials dataset developed using past experimental work comprising several important magnetocaloric material classes such as La(Fe,Si/Al)13, heusler alloys, manganites, Gd5(Si,Ge)4 family, rare-earth and metallic glasses as well as Laves phase compounds with their reported magnetic entropy changes, -ΔSM(T,H). Notable linear and non-linear machine learning models are implemented to predict the -ΔSM(T,H) of materials. Our analyses indicate that the Random Forest model outperforms the others with R2 of 0.82. We then use this model to screen a large magnetic materials database with nearly 40,000 compounds to identify potential new magnetocaloric materials operating near room temperature. MnGa2Sb2, CrGa2Sb2, SbSCl0.1I0.9, Sm3Te4, LaRhSn, SbSI, Tl0.58Rb0.42Fe1.72Se2, Cs0.86Fe1.66Se2, La2.1MnGe2.2 are some of the newly predicted compounds that could yield large magnetocaloric cooling performance."This article is published as Ucar, Huseyin, Durga Paudyal, and Kamal Choudhary. "Machine learning predicted magnetic entropy change using chemical descriptors across a large compositional landscape." Computational Materials Science 209 (2022): 111414.
DOI: 10.1016/j.commatsci.2022.111414.
Copyright 2022 The Author(s).
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).
Posted with permission.
DOE Contract Number(s): AC02-07CH11358
Safety science special issue “safety in low- and middle-income countries”
No full textGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Safety and Security Scienc
Characterizations of Soil Layers Artificially Deposited on Glass and Photovoltaic Coupons
No full textabstract: The deposition of airborne dust, especially in desert conditions, is very problematic as it leads to significant loss of power of photovoltaic (PV) modules on a daily basis during the dry period. As such, PV testing laboratories around the world have been trying to set up soil deposition stations to artificially deposit soil layers and to simulate outdoor soiling conditions in an accelerated manner. This thesis is a part of a twin thesis. The first thesis, authored by Shanmukha Mantha, is associated with the designing of an artificial soiling station. The second thesis (this thesis), authored by Darshan Choudhary, is associated with the characterization of the deposited soil layers. The soil layers deposited on glass coupons and one-cell laminates are characterized and presented in this thesis. This thesis focuses on the characterizations of the soil layers obtained in several soiling cycles using various techniques including current-voltage (I-V), quantum efficiency (QE), compositional analysis and optical profilometry. The I-V characterization was carried out to determine the impact of soil layer on current and other performance parameters of PV devices. The QE characterization was carried out to determine the impact of wavelength dependent influence of soil type and thickness on the QE curves. The soil type was determined using the compositional analysis. The compositional data of the soil is critical to determine the adhesion properties of the soil layers on the surface of PV modules. The optical profilometry was obtained to determine the particle size and distribution. The soil layers deposited using two different deposition techniques were characterized. The two deposition techniques are designated as “dew” technique and “humidity” technique. For the same deposition time, the humidity method was determined to deposit the soil layer at lower rates as compared to the dew method. Two types of deposited soil layers were characterized. The first type layer was deposited using a reference soil called Arizona (AZ) dust. The second type layer was deposited using the soil which was collected from the surface of the modules installed outdoor in Arizona. The density of the layers deposited using the surface collected soil was determined to be lower than AZ dust based layers for the same number of deposition cycles.Dissertation/ThesisMasters Thesis Engineering 201
Prevalence and determinants of musculoskeletal pain among school-going children carrying schoolbags: A cross-sectional study from Central India
No full textMusculoskeletal disorders constitute 1,194 prevalent cases per 1,00,000 among children aged 5 to 19 years in India. School bags with a weight exceeding 10% of the bodyweight is a common cause of backache in school children. Methods: School children aged 8–15 years from four private schools of Bhopal were included, resulting in a sample of 934 participants. An author-assisted questionnaire was used for data collection. Results: The school bags were 16.5% of the average weight of students. 55.9% of the students experienced pain in the last 12 months, 41.6% in the last ten days and 21.3% had visited a doctor for the same. On analysis, bags with ≥ three compartments (AOR: 3.17), using both shoulders to carry bags (AOR: 0.10), and the absence of lockers in schools (AOR: 17.80) were significant predictors of pain in the last ten days (P < 0.05). Conclusion: Massive advocacy and orientation are required at all levels for educational administrators, teachers, parents and students
NiTi/Pb(Zr₀.₅₂Tiₒ.₄₈)O₃ thin film heterostructures for vibration damping in MEMS
No full textWe report on the damping properties of NiTi/Pb(Zr₀.₅₂Tiₒ.₄₈)O₃ (PZT) heterostructures using nanoindentation technique. Creep and impact tests were performed to obtain hardness (H), elastic modulus (Er), damping factor (tan δ) and figure of merit (FOM. A hold time of 30 s during creep test shows significant improvement in damping factor for NiTi/PZT (0.046) and CrTiN/NiTi/PZT (0.050). Impact test demonstrates highest damping capacity with lowest coefficient of restitution (0.30) in CrTiN/NiTi/PZT. Higher hardness (19.8 GPa) and excellent figure of merit (0.751) in CrTiN/NiTi/PZT makes them very attractive damping material for microelectromechanical systems (MEMS).sponsorship: The financial support provided by Department of Information Technology (DIT), India under Nanotechnology Initiative Program with Reference Grant No. 20(11)/2007-VCND and DRDO ARMREB is highly acknowledged. We are thankful to Professor A.R. Kulkarni, IIT Mumbai, India and Dr. D. K. Kharat, Director DRDO Head Quarters, New Delhi for fruitful discussions. The author Nitin Choudhary is thankful to UGC, India for the award of SRF. (Department of Information Technology (DIT), India under Nanotechnology Initiative Program|20(11)/2007-VCND, DRDO ARMREB, UGC, India)status: Publishe
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