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https://www.readbyqxmd.com/read/29786971/intergenerational-teen-pregnancy-a-population-based-cohort-study
#1
Ning Liu, Simone N Vigod, M Michèle Farrugia, Marcelo L Urquia, Joel G Ray
OBJECTIVE: To estimate the intergenerational association in teenage pregnancy, and whether there is a coupling tendency between a mother and daughter in how their teen pregnancies end, such as an induced abortion (IA) vs. a livebirth. DESIGN: Population-based cohort study. SETTING: Ontario, Canada. POPULATION: 15,097 mothers and their 16,177 daughters. METHODS: Generalized estimating equations generated adjusted odds ratios (aOR) of a daughter experiencing a teen pregnancy in relation to the number of teen pregnancies her mother had...
May 22, 2018: BJOG: An International Journal of Obstetrics and Gynaecology
https://www.readbyqxmd.com/read/29786963/design-and-fabrication-of-printed-paper-based-hybrid-micro-supercapacitor-by-using-graphene-and-redox-active-electrolyte
#2
Bhawna Nagar, Deepak P Dubal, Luis Pires, Arben Merkoçi, Pedro Gómez-Romero
Inspired by future needs of flexible, simple, and low-cost energy storage devices, smart graphene-based micro-supercapacitors on conventional Xerox paper substrates were developed. The use of redox-active species (iodine redox couple) was explored to further improve the paper device's performance. The device based on printed graphene paper itself already had a remarkable maximum volumetric capacitance of 29.6 mF cm-3 (volume of whole device) at 6.5 mA cm-3 . The performance of the hybrid electrode with redox-active potassium iodide at the graphene surface was tested...
May 22, 2018: ChemSusChem
https://www.readbyqxmd.com/read/29786941/a-regio-and-diastereoselective-anodic-aryl-aryl-coupling-in-the-biomimetic-total-synthesis-of-thebaine
#3
Alexander Lipp, Dorota Ferenc, Christoph Gütz, Mario Geffe, Nina Vierengel, Dieter Schollmeyer, Hans Jürgen Schäfer, Siegfried R Waldvogel, Till Opatz
The biosynthesis of thebaine is based on the regioselective, intramolecular, oxidative coupling of (R)-reticuline. For decades, chemists have sought to mimic this coupling using stoichiometric oxidants. However, all approaches suffered from low yields or the formation of undesired regioisomers. Electrochemistry would represent a sustainable alternative in this respect but all attempts to accomplish an electrochemical synthesis of thebaine have failed so far. Herein, a regioselective and diastereoselective anodic coupling of 3',4',5'-trioxygenated laudanosine derivatives is presented, which finally enabled an electrochemical access to (-)-thebaine...
May 22, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/29786930/an-unexpected-%C3%AE-oxidation-of-cyclic-ketones-with-1-4-benzoquinone-via-enol-catalysis
#4
Benjamin List, Grigory A Shevchenko, Barry Oppelaar
The single electron oxidation of enamines is a well-established activation mode for organocatalytic enantioselective α-functionalizations of simple aldehydes and ketones.[1] Due to the intrinsic limitations of enamine catalysis, the oxidation of the corresponding α-branched ketones has so far not been reported. Herein we disclose the first direct and asymmetric α-aryloxylation of cyclic ketones via enol catalysis, using quinones as the reaction partner. Catalytic amounts of a phosphoric acid promote the exclusive formation of α,α-disubstituted ketones from the corresponding α-substituted ketones in good yields and enantioselectivities (up to 96...
May 22, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/29786926/catalytic-thorpe-ingold-effect-for-branch-selective-alkylation-of-unactivated-aryl-fluorides
#5
Matthew J O'Neill, Tim Riesebeck, Josep Cornella
Herein, we present a general protocol for the alkylation of simple aryl fluorides with unbiased secondary Grignard reagents by means of Ni catalysis. This study revealed a general Thorpe-Ingold effect in the ligand backbone which confers a high degree of selectivity for the secondary position in the C-C coupling event. Such protocol is characterized by its mild conditions, robustness and simplicity. Both electron-rich and electron-deficient aryl fluorides are suitable candidates in this transformation. Equally amenable are a variety of heterocycles, permitting the coupling without over alkylation at the electrophilic sites...
May 22, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/29786903/copper-catalyzed-allylic-c-h-alkynylation-via-cross-dehydrogenative-coupling
#6
Ahmad A Almasalma, Esteban Mejía
C-H bond functionalization is a well-developed concept that has been thoroughly studied and gives entry to rather complex molecules without the need of previous derivatization of the substrates, although the use of copper complexes for allylic C-H bond functionalization under oxidative conditions as an alternative to the well-established palladium-based methodologies remains largely underdeveloped. Here we show for the first time a selective cross-dehydrogenative coupling reaction between underivatized allylic substrates and terminal alkynes to produce 1,4-enynes in high yields in a single step, using an in situ synthesized copper catalyst and an oxidant...
May 22, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29786871/gender-specific-effects-of-selection-for-drinking-in-the-dark-on-the-network-roles-of-coding-and-non-coding-rnas
#7
Ovidiu Dan Iancu, Alex Colville, Beth Wilmot, Robert Searles, Priscila Darakjian, Christina Zheng, Shannon McWeeney, Sunita Kawane, John C Crabbe, Pamela Metten, Denesa Oberbeck, Robert Hitzemann
BACKGROUND: Transcriptional differences between Heterogeneous stock (HS/NPT) mice and High Drinking in the Dark (HDID) selected mouse lines have previously been described based on microarray technology coupled with network based analysis (Iancu et al., 2013b). The network changes were reproducible in two independent selections and largely confined to two distinct network modules; in contrast differential expression appeared more specific to each selected line. The current study extends these results by utilizing RNA-Seq technology, allowing evaluation of the relationship between genetic risk and transcription of non-coding RNA; we additionally evaluate sex-specific transcriptional effects of selection...
May 22, 2018: Alcoholism, Clinical and Experimental Research
https://www.readbyqxmd.com/read/29786855/speciation-of-bio-available-iodine-in-abalone-haliotis-discus-hannai-by-high-performance-liquid-chromatography-hyphenated-with-inductively-coupled-plasma-mass-spectrometry-using-an-in-vitro-method
#8
Han Sol Doh, Hyun Jin Park
Abalone is one of the most valuable marine products found in East Asia because it is rich in nutritious substances including iodine. In this study, the in vitro dialyzability approach was used to assess the bio-available iodine species in abalone. Iodide, iodate, 3-iodo-L-tyrosine (MIT), and 3,5-diiodo-L-tyrosine (DIT) were separated by high-performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). To assure the consistency, reliability, and accuracy of the data, the method was validated...
May 22, 2018: Journal of Food Science
https://www.readbyqxmd.com/read/29786747/microrna-137-dysregulation-predisposes-to-osteoporotic-fracture-by-impeding-alp-activity-and-expression-via-suppression-of-leucine-rich-repeat-containing-g-protein-coupled-receptor-4-expression
#9
Xiangjun Liu, Xiaohui Xu
Osteoporosis is defined as a loss of bone mass and deterioration of its architecture resulting in bone weakness, which becomes prone to fracture. The objective of this study was to investigate the molecular mechanism by which miR-137 can reduce the risk of fracture in patients with osteoporosis. An online miRNA database and a luciferase reporter assay system were used to confirm that leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4) was the target of miR-137. Real-time PCR and western blot analysis were used to study miR-137 mRNA, the expression of LGR4 mRNA and protein among different groups or cells transfected with a scrambled miRNA control, miR-137 mimic, LGR4 siRNA and miR-137 inhibitor...
May 17, 2018: International Journal of Molecular Medicine
https://www.readbyqxmd.com/read/29786741/halo-substituted-benzenesulfonyls-and-benzenesulfinates-convenient-sources-of-arenes-in-metal-catalyzed-c-c-bond-formation-reactions-for-the-straightforward-access-to-halo-substituted-arenes
#10
REVIEW
Haoran Li, Arpan Sasmal, Xinzhe Shi, Jean-François Soulé, Henri Doucet
Palladium-catalyzed reactions using aryl halides as one of the coupling partners represent a very popular method for generating carbon-carbon bonds. However, such couplings suffer from important limitations. As most palladium catalysts are very effective for the cleavage of C-halo bonds (Halo = Cl, Br or I), in many cases, the presence of several halide functional groups on arenes is not tolerated. Since two decades, and especially during the last few years, a new class of coupling partners, benzenesulfonyl and benzenesulfinate derivatives, has emerged as a powerful alternative to aryl halides for the Pd-catalyzed C-C bond formation, as the reactions performed with these substrates generally tolerate C-halo bonds...
May 22, 2018: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/29786740/shear-density-coupling-for-a-compressible-single-component-yield-stress-fluid
#11
Markus Gross, Fathollah Varnik
Flow behavior of a single-component yield stress fluid is addressed on the hydrodynamic level. A basic ingredient of the model is a coupling between fluctuations of density and velocity gradient via a Herschel-Bulkley-type constitutive model. Focusing on the limit of low shear rates and high densities, the model approximates well-but is not limited to-gently sheared hard sphere colloidal glasses, where solvent effects are negligible. A detailed analysis of the linearized hydrodynamic equations for fluctuations and the resulting cubic dispersion relation reveals the existence of a range of densities and shear rates with growing flow heterogeneity...
May 22, 2018: Soft Matter
https://www.readbyqxmd.com/read/29786725/a-convergent-strategy-towards-febrifugine-and-related-compounds
#12
T M M Maiden, N Mbelesi, P A Procopiou, S Swanson, J P A Harrity
We report a modular five step synthetic route to the febrifugines that employs 2-(chloromethyl)allyl-trimethylsilane as a conjunctive reagent for the coupling of the piperidine and quinazolinone groups. We also demonstrate the application of a recent Rh-catalyzed quinazolinone synthesis for the facile generation of febrifugine analogs.
May 22, 2018: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/29786720/a-strain-induced-subwavelength-structure-for-a-haze-free-and-highly-transparent-flexible-plastic-substrate
#13
Jae Yong Park, Juyoung Ham, Illhwan Lee, Jong-Lam Lee
This paper presents a method to produce subwavelength-scale (<250 nm) AgCl nanostructures on a flexible plastic film, which is indispensable for highly efficient flexible displays. Using Cl2 plasma treatment on an Ag-coated plastic film, AgCl nanostructures were produced through the reaction of Ag atoms with Cl radicals. During the reaction, the volume of AgCl expands, leading to drastically changed surface morphology from a two-dimensional (2D) flat Ag surface to a 3D subwavelength-scale AgCl nanostructure...
May 22, 2018: Nanoscale
https://www.readbyqxmd.com/read/29786695/the-asthma-mobile-health-study-smartphone-data-collected-using-researchkit
#14
Yu-Feng Yvonne Chan, Brian M Bot, Micol Zweig, Nicole Tignor, Weiping Ma, Christine Suver, Rafhael Cedeno, Erick R Scott, Steven Gregory Hershman, Eric E Schadt, Pei Wang
Widespread adoption of smart mobile platforms coupled with a growing ecosystem of sensors including passive location tracking and the ability to leverage external data sources create an opportunity to generate an unprecedented depth of data on individuals. Mobile health technologies could be utilized for chronic disease management as well as research to advance our understanding of common diseases, such as asthma. We conducted a prospective observational asthma study to assess the feasibility of this type of approach, clinical characteristics of cohorts recruited via a mobile platform, the validity of data collected, user retention patterns, and user data sharing preferences...
May 22, 2018: Scientific Data
https://www.readbyqxmd.com/read/29786694/spin-supersolid-phase-in-coupled-alternating-spin-chains
#15
F Heydarinasab, J Abouie
We study the ground state phase diagram of a two dimensional mixed-spin system of coupled alternating spin-1 and 1/2 chains with a stripe supersolid phase. Utilizing different analytical and numerical approaches such as mean field approximation, cluster mean field theory and linear spin wave theory, we demonstrate that our system displays a rich ground state phase diagram including novel stripe supersolid, solids with different fillings and super-counterfluid phases, in addition to a stripe solid with half filling, superfluid and Mott insulating phases...
May 21, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29786662/study-on-the-discrimination-between-citri-reticulatae-pericarpium-varieties-based-on-hs-spme-gc-ms-combined-with-multivariate-statistical-analyses
#16
Yuying Zheng, Xuan Zeng, Wei Peng, Zhong Wu, Weiwei Su
Citri reticulatae pericarpium (CRP), the dried pericarps of Citrus reticulata Blanco and its cultivars, has been widely used in drugs and foods in China for centuries. In this study, an accurate and feasible analytical method based on HS-SPME-GC-MS coupled with multivariate statistical analyses was developed to comprehensively compare volatile compounds of pericarps derived from Citrus reticulata "Chachi" ("Guangchenpi" in Chinese, GCP) and other cultivars of Citrus reticulata Blanco ("Chenpi" in Chinese, CP)...
May 22, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29786562/application-of-hepatocyte-like-cells-to-enhance-hepatic-safety-risk-assessment-in-drug-discovery
#17
REVIEW
Dominic P Williams
Hepatic stress and injury from drugs continues to be a major concern within the pharmaceutical industry, leading to preclinical and clinical attrition precautionary warnings and post-market withdrawal of drugs. There is a requirement for more predictive and mechanistically accurate models to aid risk assessment. Primary human hepatocytes, subject to isolation stress, cryopreservation, donor-to-donor variation and a relatively short period of functional capability in two-dimensional cultures, are not suitable for high-throughput screening procedures...
July 5, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
https://www.readbyqxmd.com/read/29786553/from-skeletal-development-to-the-creation-of-pluripotent-stem-cell-derived-bone-forming-progenitors
#18
REVIEW
Wai Long Tam, Frank P Luyten, Scott J Roberts
Bone has many functions. It is responsible for protecting the underlying soft organs, it allows locomotion, houses the bone marrow and stores minerals such as calcium and phosphate. Upon damage, bone tissue can efficiently repair itself. However, healing is hampered if the defect exceeds a critical size and/or is in compromised conditions. The isolation or generation of bone-forming progenitors has applicability to skeletal repair and may be used in tissue engineering approaches. Traditionally, bone engineering uses osteochondrogenic stem cells, which are combined with scaffold materials and growth factors...
July 5, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
https://www.readbyqxmd.com/read/29786505/can-pallars-i-llobateres-a-new-hominoid-bearing-locality-from-the-late-miocene-of-the-vall%C3%A3-s-pened%C3%A3-s-basin-ne-iberian-peninsula
#19
David M Alba, Isaac Casanovas-Vilar, Marc Furió, Israel García-Paredes, Chiara Angelone, Sílvia Jovells-Vaqué, Àngel H Luján, Sergio Almécija, Salvador Moyà-Solà
In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to the Vallès-Penedès Basin. Here we report a new hominoid maxillary fragment with M2 from this basin. It was surface-collected in March 2017 from the site of Can Pallars i Llobateres (CPL, Sant Quirze del Vallès), where fossil apes had not been previously recorded. The locality of provenance (CPL-M), which has delivered no further fossil remains, is located very close (ca. 50 m) to previously known CPL outcrops, and not very far (ca...
May 18, 2018: Journal of Human Evolution
https://www.readbyqxmd.com/read/29786486/one-year-retention-of-gadolinium-in-the-brain-comparison-of-gadodiamide-and-gadoterate-meglumine-in-a-rodent-model
#20
Philippe Robert, Stefanie Fingerhut, Cécile Factor, Véronique Vives, Justine Letien, Michael Sperling, Marlène Rasschaert, Robin Santus, Sébastien Ballet, Jean-Marc Idée, Claire Corot, Uwe Karst
Purpose To compare the long-term brain elimination kinetics and gadolinium species in healthy rats after repeated injections of the contrast agents gadodiamide (a linear contrast agent) or gadoterate (a macrocyclic contrast agent). Materials and Methods Nine-week-old rats received five doses of 2.4 mmol gadolinium per kilogram of body weight over 5 weeks and were followed for 12 months with T1-weighted MRI (n = 140 rats, corresponding to seven time points, two contrast agents, and 10 rats per group). Animals were sacrificed at 1 week, 1 month, and 2, 3, 4, 5, and 12 months after the last injection...
May 17, 2018: Radiology
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