Low-temperature phase of hexaguanidinium hepta­molybdate monohydrate

The crystal structure of the title compound, [C(NH2)3]6[Mo7O24]·H2O, previously determined at room temperature in the monoclinic space group C2/c from Weissenberg techniques [Don & Weakley (1981 ▶). Acta Cryst. B37, 451–453], has been redetermined from low-temperature single-crystal data in the monoclinic space group P21/c. The asymmetric unit contains one hepta­molybdate anion, six guanidinium cations and one water mol­ecule of hydration. The anions and cations are linked by an extensive network of N—H⋯O hydrogen bonds

Processos julgados pela CVM: análise das principais infrações cometidas por auditores independentes

Este estudo analisa as principais infrações cometidas por auditores independentes na esfera da Comissão de Valores Mobiliários. Mediante a emissão do relatório de auditoria, o auditor independente deve atestar a credibilidade das demonstrações financeiras elaboradas pela entidade auditada. Entretanto, nas últimas décadas, foram inúmeros os casos de fraudes e erros contábeis envolvendo auditores independentes que resultam em processos devido à sua conivência ou simplesmente ineficiência. O estudo utiliza-se de uma pesquisa aplicada, documental, bibliográfica e descritiva. Para seu desenvolvimento foram coletadas informações de 86 processos administrativos sancionadores julgados pela CVM, no período de 2010 a 2019, através do site da entidade, utilizando o filtro “SNC”, dentre os quais 66 se aplicam à pesquisa. Por meio da análise quali-quantitativa foram evidenciadas 74 infrações, sendo as mais recorrentes: d) “Ausência de planejamento e procedimentos de auditoria que acarretam em divergências no relatório do auditor independente” e b) “Irregularidades no Programa de Revisão Externa de Qualidade”, que representam 39,19% e 35,14% da amostra analisada, respectivamente. Também se buscou outras características dos processos, como: o perfil dos acusados e as penalidades aplicadas, com a intenção de identificar se há alguma relação direta dessas variáveis com as infrações cometidas. Na análise de correlação, identificou-se que a ocorrência da infração “b” está vinculada com os acusados “reincidentes” e com a penalidade “suspensão temporária”. Além disso, evidenciou-se que o aumento de acusados “reincidentes” está ligado principalmente ao aumento de acusados classificados como “não Big Four”

Interaction of some polyoxotunstates with acetylcholinesterase

Polyoxometalates (POMs) are polyanionic oligomeric aggregates of transition metal ions, such as tungsten, molybdenum, vanadium, etc. held together by oxygen bridges, with a high density of negative charge. They are relatively stable, some even highly stable in aqueous solutions at biological pH values. In addition to applications in catalysis, separations, analysis, and as electrondense imaging agents, some of these complexes have been shown to exhibit biological activity in vitro as well as in vivo ranging from anti-cancer, antibiotic, and antiviral to antidiabetic effects. Recent investigations reported some polyoxotungstates as reversible inhibitors of acetylcholinesterase (AChE), making them potential anti-Alzheimer’s drugs. AChE is a serine hydrolase mainly found at neuromuscular junctions and cholinergic brain synapses. Its principal biological role is the termination of impulse transmission at cholinergic synapses. Reversible inhibitors of AChE mostly have therapeutic applications, while toxic effects are associated with irreversible AChE activity modulators. Reversible inhibitors play an important role in the pharmacological manipulation of the enzyme activity, and have been applied in the diagnostic and/or treatment of various diseases such as: myasthenia gravis, AD, postoperative ileus, bladder distention, glaucoma, as well as antidote to anticholinergic overdose. The effect of four new synthesized polyoxotungstates soluble in water on AChE activity was studied. AChE is purified from electric eel and commercially available. The enzyme was treated in vitro with polyoxotungstates in the concentration range from 1 × 10-7 to 1 × 10-3 mol/L at 37ºC for 15 minutes, and the incubation time was 12 min. The obtained dependence remaining enzyme activity vs. the inhibitor concentration fitted the sigmoidal function. IC50values, indicating the enzyme sensitivity toward the inhibitor and the inhibitory capacity of the analyzed compounds, were determined from the inhibition sigmoidal curves. Na10[H2W12O42] × 27H2O did not markedly reduce AChE activity at the highest investigated concentration (1 mmol/L). K7[SiV3W9O40] × 10H2O exhibited a weak inhibitory potential, causing 50% decrease in the enzyme activity at 5 × 10-4 mol/L. However, AChE sensitivity in the presence of K7[Ti2PW10O40] was several hundred times higher, reaching IC50 at 1.15 × 10-6 mol/L. Furthermore, (NH4)14[NaP5W30O110] × 31H2O demonstrated the strongest capacity to inhibit AChE. In the presence of its low concentration of 2 × 10-8 mol/L, the enzyme activity was noticeably reduced related to the control value (obtained without inhibitor), while 50% decrease in AChE activity was achieved at 3.8 × 10-7 mol/L.Fourth International Conferenceon Radiation and Applications in Various Fields of Research, RAD 2016, May 23-27, 2016, Niš, Serbi

The burden of critical illness in hospitalized children in low- and middle-income countries: Protocol for a systematic review and meta-analysis

BACKGROUND: The majority of childhood deaths occur in low- and middle-income countries (LMICs). Many of these deaths are avoidable with basic critical care interventions. Quantifying the burden of pediatric critical illness in LMICs is essential for targeting interventions to reduce childhood mortality. OBJECTIVE: To determine the burden of hospitalization and mortality associated with acute pediatric critical illness in LMICs through a systematic review and meta-analysis of the literature. DATA SOURCES AND SEARCH STRATEGY: We will identify eligible studies by searching MEDLINE, EMBASE, CINAHL, and LILACS using MeSH terms and keywords. Results will be limited to infants or children (ages \u3e28 days to 12 years) hospitalized in LMICs and publications in English, Spanish, or French. Publications with non-original data (e.g., comments, editorials, letters, notes, conference materials) will be excluded. STUDY SELECTION: We will include observational studies published since January 1, 2005, that meet all eligibility criteria and for which a full text can be located. DATA EXTRACTION: Data extraction will include information related to study characteristics, hospital characteristics, underlying population characteristics, patient population characteristics, and outcomes. DATA SYNTHESIS: We will extract and report data on study, hospital, and patient characteristics; outcomes; and risk of bias. We will report the causes of admission and mortality by region, country income level, and age. We will report or calculate the case fatality rate (CFR) for each diagnosis when data allow. CONCLUSIONS: By understanding the burden of pediatric critical illness in LMICs, we can advocate for resources and inform resource allocation and investment decisions to improve the management and outcomes of children with acute pediatric critical illness in LMICs

How knowledge of context and radicals influences a person's ability to learn to read Chinese characters

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 36).Learning a new language is not always easy. This is particularly the case for native English speakers, who are used to letters combining to form words and tones expressing emotion, trying to learn Chinese. Mandarin Chinese is a logographic language, meaning that each character represents a word and voice tone is used to differentiate between what would otherwise be homophones. In this thesis, I present two hypothesized methods for improving a student's ability to learn to recognize Chinese characters. The first is the use of radicals, components that make up Chinese characters almost like letters make up English words. The second is the use of studying example sentences when learning new words. To test these hypotheses, I performed a pilot experiment using 10 MIT undergraduate students, none of whom were native speakers of Mandarin Chinese. There were not enough Chinese II students to test the second hypotheses, but the results suggest that the use of radicals does improve a student's ability to learn to recognize characters both more correctly and more quickly.by Tanya M. Kortz.M.Eng

Metabolomics of dietary fatty acid restriction in patients with phenylketonuria

Patients with phenylketonuria (PKU) have to follow a lifelong phenylalanine restricted diet. This type of diet markedly reduces the intake of saturated and unsaturated fatty acids especially long chain polyunsaturated fatty acids (LC-PUFA). Long-chain saturated fatty acids are substrates of mitochondrial fatty acid oxidation for acetyl-CoA production. LC-PUFA are discussed to affect inflammatory and haemostaseological processes in health and disease. The influence of the long term PKU diet on fatty acid metabolism with a special focus on platelet eicosanoid metabolism has been investigated in the study presented here. 12 children with PKU under good metabolic control and 8 healthy controls were included. Activated fatty acids (acylcarnitines C6-C18) in dried blood and the cholesterol metabolism in serum were analyzed by liquid chromatographic tandem mass spectrometry (LC-MS/MS). Fatty acid composition of plasma glycerophospholipids was determined by gas chromatography. LC-PUFA metabolites were analyzed in supernatants by LC-MS/MS before and after platelet activation and aggregation using a standardized protocol. Patients with PKU had significantly lower free carnitine and lower activated fatty acids in dried blood compared to controls. Phytosterols as marker of cholesterol (re-) absorption were not influenced by the dietary fatty acid restriction. Fatty acid composition in glycerophospholipids was comparable to that of healthy controls. However, patients with PKU showed significantly increased concentrations of y-linolenic acid (C18:3n-6) a precursor of arachidonic acid. In the PKU patients significantly higher platelet counts were observed. After activation with collagen platelet aggregation and thromboxane B(2) and thromboxane B(3) release did not differ from that of healthy controls. Long-term dietary fatty acid restriction influenced the intermediates of mitochondrial beta-oxidation. No functional influence on unsaturated fatty acid metabolism and platelet aggregation in patients with PKU was detected

Tunable electrochromic filter for in situ Fourier spatial frequency filtering

Spatial optical Fourier filtering is a widespread technique for in situ image or light field processing. However, conventional fixed absorbing patterns or mechanical irises only allow an inflexible, very restricted control. Thus, we present two electrochromic spatial filters with ring-shaped or directional segments, which can be individually addressed and continuously tuned in transmission resulting in up to 512 different filtering states. For realization of the electrochromic devices, we overcome technical obstacles to realize seamless, gap-free electrochromic segments. We describe this novel fabrication process and demonstrate the successful application in an optical Fourier transform set-up