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Oxidation of a series of Cr

The ligand electronics of salen manganese nitride complexes directly influence the locus of oxidation and, thus, the reactivity of the resulting oxidized species. This work investigates the influence of tert-butoxy, isopropoxy, and methoxy substituents on the electronics of salen manganese nitride species and includes the first documentation of the para Hammett value for the tert-butoxy substituent (σpara = -0.13 ± 0.03). Each alkoxy-substituted complex undergoes metal-based oxidation to form manganese(VI), and the kinetics of bimolecular homocoupling to form N2 were assessed by cyclic voltammetry. Bis-oxidation of the manganese complexes was investigated at low temperature using cyclic voltammery and UV-vis-near-IR spectroscopy, and in combination with theoretical calculations, plausible electronic structures of the dications are provided.

Poly(methylhydrosiloxane) (PMHS) has been examined for its ability to reduce and subsequently cyclize carbohydrate substrates using catalytic tris(pentafluorophenyl)borane (BCF). The work herein is the first reported example of the direct conversion of monosaccharides to 1,4-anhydro and 2,5-anhydro products utilizing a hydrosiloxane reducing agent. PMHS is produced from waste products of the silicone industry, making it a green alternative to traditional hydrosilane reducing agents. This work thus contributes to the goal of utilizing renewable feedstocks in the production of fine-chemicals.

Although there are many recognized health benefits for the consumption of omega-3 (n-3) long-chain polyunsaturated fatty acids (LCPUFA), intake in the United States remains below recommended amounts. This analysis was designed to provide an updated assessment of fish and n-3 LCPUFA intake (eicosapentaenoic (EPA), docosahexaenoic acid (DHA), and EPA+DHA) in the United States adult population, based on education, income, and race/ethnicity, using data from the 2003-2014 National Health and Nutrition Examination Survey (NHANES) (n = 44,585). Over this survey period, participants with less education and lower income had significantly lower n-3 LCPUFA intakes and fish intakes (p &lt, 0.001 for all between group comparisons). N-3 LCPUFA intake differed significantly according to ethnicity (p &lt, 0.001), with the highest intake of n-3 LCPUFA and fish in individuals in the &ldquo, Other&rdquo, category (including Asian Americans). Supplement use increased EPA + DHA intake, but only 7.4% of individuals consistently took supplements. Overall, n-3 LCPUFA intake in this study population was low, but our findings indicate that individuals with lower educational attainment and income are at even higher risk of lower n-3 LCPUFA and fish intake.

Background During the past two decades, the number and complexity of clinical trials have risen dramatically increasing the difficulty of choosing sites for inspection. FDA's resources are limited and so sites should be chosen with care. Purpose To determine if data mining techniques and/or unsupervised statistical monitoring can assist with the process of identifying potential clinical sites for inspection. Methods Five summary-level clinical site datasets from four new drug applications (NDA) and one biologics license application (BLA), where the FDA had performed or had planned site inspections, were used. The number of sites inspected and the results of the inspections were blinded to the researchers. Five supervised learning models from the previous two years (2016-2017) of an on-going research project were used to predict site inspections results, i.e., No Action Indicated (NAI), Voluntary Action Indicated (VAI), or Official Action Indicated (OAI). Statistical Monitoring Applied to Research Trials (SMARTTM) software for unsupervised statistical monitoring software developed by CluePoints (Mont-Saint-Guibert, Belgium) was utilized to identify atypical centers (via a p-value approach) within a study.Finally, Clinical Investigator Site Selection Tool (CISST), developed by the Center for Drug Evaluation and Research (CDER), was used to calculate the total risk of each site thereby providing a framework for site selection. The agreement between the predictions of these methods was compared. The overall accuracy and sensitivity of the methods were graphically compared. Results Spearman's rank order correlation was used to examine the agreement between the SMARTTM analysis (CluePoints' software) and the CISST analysis. The average aggregated correlation between the p-values (SMARTTM) and total risk scores (CISST) for all five studies was 0.21, and range from -0.41 to 0.50. The Random Forest models for 2016 and 2017 showed the highest aggregated mean agreement (65.1%) amongst outcomes (NAI, VAI, OAI) for the three available studies. While there does not appear to be a single most accurate approach, the performance of methods under certain circumstances is discussed later in this paper. Limitations Classifier models based on data mining techniques require historical data (i.e., training data) to develop the model. There is a possibility that sites in the five-summary level datasets were included in the training datasets for the models from the previous year's research which could result in spurious confirmation of predictive ability. Additionally, the CISST was utilized in three of the five site selection processes, possibly biasing the data. Conclusion The agreement between methods was lower than expected and no single method emerged as the most accurate.

The long-chain n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), play a crucial role in health, but previous National Health and Nutrition Examination Survey (NHANES) analyses have shown that EPA and DHA intake in the United States is far below recommendations (~250-500 mg/day EPA + DHA). Less is known about docosapentaenoic acid (DPA), the metabolic intermediate of EPA and DHA; however, evidence suggests DPA may be an important contributor to long-chain n-3 fatty acid intake and impart unique benefits. We used NHANES 2003-2014 data (n = 45,347) to assess DPA intake and plasma concentrations, as well as the relationship between intake and plasma concentrations of EPA, DPA, and DHA. Mean DPA intake was 22.3 ± 0.8 mg/day from 2013 to 2014, and increased significantly over time (p < 0.001), with the lowest values from 2003 to 2004 (16.2 ± 1.2 mg/day). DPA intake was higher in adults (20-55 years) and seniors (55+ years) compared to younger individuals. In regression analyses, DPA intake was a significant predictor of plasma EPA (β = 138.5; p < 0.001) and DHA (β = 318.9; p < 0.001). Plasma DPA was predicted by EPA and DHA intake (β = 13.15; p = 0.001 and β = 7.4; p = 0.002), but not dietary DPA (p = 0.3). This indicates that DPA intake is not a good marker of plasma DPA status (or vice versa), and further research is needed to understand the factors that affect the interconversion of EPA and DPA. These findings have implications for future long-chain n-3 fatty acids dietary recommendations.

Despite the importance of n-3 fatty acids for health, intakes remain below recommended levels. The objective of this study was to provide an updated assessment of fish and n-3 fatty acid intake (i.e., eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and EPA+DHA) in the United States using the 2003&ndash, 2014 National Health and Nutrition Examination Survey (NHANES) data (n = 45,347)). Over this survey period, toddlers, children, and adolescents (aged 1&ndash, 19) had significantly lower n-3 fatty acid intake (p &lt, 0.001) compared to adults and seniors, which remained significant after adjusting for caloric intake. Females demonstrated lower n-3 fatty acid intake than males (p &lt, 0.001), with adult and senior women having significantly lower intakes compared to men in the same age categories (p &lt, 0.001) after adjustment for energy intake. Women also consumed less fish than men (5.8 versus 6.1 servings/month, p &lt, 0.001). The estimated intakes of n-3 fatty acids in pregnant women did not differ from non-pregnant women (p = 0.6 for EPA+DHA), although pregnant women reported consuming less high n-3 fatty acid-containing fish than non-pregnant women (1.8 versus 2.6 servings/month, p &lt, 0.001). Our findings indicate that subgroups of the population may be at higher risk of n-3 fatty acid intakes below recommended levels.

Objectives: Moderate-to-vigorous physical activity provides multiple benefits to women after childbirth. To achieve these benefits, the recommendation that adults obtain, 150 min of moderate-to-vigorous physical activity per week and reduce sedentary behaviors, also applies to women in the post-partum phase of the life span. However, research examining the moderate-to-vigorous physical activity and sedentary behaviors of women with young children (0–2 years) is limited. A greater understanding of these behaviors from a nationally representative sample is needed. Therefore, the primary objective of this study was to determine the levels of moderate-to-vigorous physical activity and sedentary behaviors of a nationally representative sample of women with young children within the United States. A secondary objective was to examine the influence of body mass index and sociodemographic factors on these behaviors. Methods: Cross-sectional data from four cycles of the National Health and Nutrition Examination Survey (2007–2008, 2009–2010, 2011–2012, and 2013–2014) were used for analysis. Descriptive statistics were calculated and a generalized linear model was used to investigate associations between mean minutes of moderate-to-vigorous physical activity, sedentary activity, body mass index, and sociodemographic variables. Discussion: Women with young children (n = 477) obtained 634 min in moderate-to-vigorous physical activity per week and this was positively associated with having a higher income (p

Upon reaction with KBEt3H, the pseudo tetrahedral Fe(II) complex 5 with a bulky enamido-phosphazide ligand set undergoes elimination of N2 and 1,3-Me2C6H4 to generate the dinuclear Fe(II) derivative 6 with bridging phosphinimido units. When the reaction is performed using KBEt3D, no deuterium is incorporated into the eliminated 1,3-Me2C6H4; all of the deuterium ends up as D2. When the reaction is performed in THF-d8, only 2-d-1,3-Me2C6H3D was detected by GCMS. These studies are consistent with a radical mechanism.

A low-coordinate iron hydride complex bearing an unsymmetrical NpN (enamido–phosphinimine) ligand scaffold was synthesized and fully characterized. Insertion reactivity with azobenzene, 3-hexyne, and 1-azidoadamantane was explored, and the isolated products were analogous to previously reported β-diketiminate iron hydride insertion products. Surprisingly, the NpN iron hydride displays unprecedented reactivity toward hexafluorobenzene, affording an NpN iron fluoride complex and pentafluorobenzene as products. The NpN iron hydride is a precatalyst for catalytic hydro-defluorination of perfluorinated aromatics in the presence of silane. Kinetic studies indicated that the rate-determining step during catalysis involved silane.

Background Recent years have seen standardization of the anatomic definitions of pancreatic adenocarcinoma, and increasing utilization of neoadjuvant therapy (NAT). The aim of the current review was to summarize the evidence for NAT in pancreatic adenocarcinoma since 2009, when consensus criteria for resectable (R), borderline resectable (BR), and locally advanced (LA) disease were endorsed. Methods PubMed search was undertaken along with extensive backward search of the references of published articles to identify studies utilizing NAT for pancreatic adenocarcinoma. Abstracts from ASCO-GI 2014 and 2015 were also searched. Results A total of 96 studies including 5520 patients were included in the final quantitative synthesis. Pooled estimates revealed 36% grade ≥ 3 toxicities, 5% biliary complications, 21% hospitalization rate and low mortality (0%, range 0–16%) during NAT. The majority of patients (59%) had stable disease. On an intention-to-treat basis, R0-resection rates varied from 63% among R patients to 23% among LA patients. R0 rates were > 80% among all patients who were resected after NAT. Among R and BR patients who underwent resection after NAT, median OS was 30 and 27.4 months, respectively. Conclusions The current study summarizes the recent literature for NAT in pancreatic adenocarcinoma and demonstrates improving outcomes after NAT compared to those historically associated with a surgery-first approach for pancreatic adenocarcinoma. Electronic supplementary material The online version of this article (10.1186/s12957-017-1240-2) contains supplementary material, which is available to authorized users.

Two-step thermochemical cycling was achieved using CeO2 with sub-micrometer sized macropores, allowing for substantially improved CO production at fast cycle rates when compared to nonporous CeO2. The effects of porosity, pore order, and packing density were probed by synthesizing ceria materials with different morphologies. Polymeric colloidal spheres were used as templates for the synthesis of three-dimensionally ordered macroporous (3DOM) CeO2 and nonordered macroporous (NOM) CeO2. Aggregated CeO2 nanoparticles with feature sizes similar to those in 3DOM CeO2 were prepared by fragmenting 3DOM CeO2 into its building blocks using ultrasonication. The three templated materials and nonporous, commercial CeO2 were tested in thermochemical cycles using an infrared furnace. CeO2 was reduced at ∼1200 °C, and the reduced CeO2−δ materials were reoxidized under CO2 at ∼850 °C. The high temperatures required for cycling induced changes in the morphology of the porous materials, which were characterized by electron...

The mechanisms driving microstructure formation in template-confined Pechini-type gel systems involving solid solutions of cerium oxide with alkaline earth metals are investigated. Three-dimensionally ordered macroporous microspheres and more extended bicontinuous networks with hierarchical porosity are synthesized directly from a Pechini sol–gel precursor within a colloidal crystal template. The type of morphology generated is related to the mechanisms of phase separation in the precursor, namely, nucleation and growth vs spinodal decomposition. These mechanisms are, in turn, determined by the citric acid concentration in the initial precursor solution and by electrostatic interactions of the precursor with the polymeric template. Microspheres generated by the nucleation-and-growth pathway can be produced between 1–3 μm in size, with polydispersities below 15%. They retain the ordered porous network left by removal of the template. The number of nucleation sites (i.e., oligomers and longer chains of comp...