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The lactones and cyclic ethers produced in the tellurocyclofunctionalization of unsaturated car☐ylic acids and alcohols are efficiently detellurated by tri-n-butyl tin hydride. Trapping of the intermediate free radicals with methyl acrylate leads to the corresponding adducts in moderate to good yields.

The theoretical formulation of the self-consistent variational cellular method (SCVCM) has been developed in order to calculate the electronic structure of crystals with an arbitrary number of atoms per unit cell. Calculations for metallic sodium and silicon have been carried out. The electronic charge density within the atomic polyhedron was calculated assuming two regions, one corresponding to the inscribed sphere and the other corresponding to the interstitial region. The radial electronic charge density in the inscribed sphere was obtained by adding a limited number of contributions of Brillouin zone states using the “mean value point theory”, developed by Baldereschi and Chadi-Cohen. In the interstitial region, the electronic density was taken as of a constant value. The model can be extended to open structures by adding empty cells. Our results for sodium and silicon are in good agreement with those obtained by other methods. The self-consistent scheme proposed is accurate and fast enough to be applied to more complex structures.

A new approach to the total synthesis of (±)Frullanolide (1), employing selenium reagents, is described. This methodology has significant advantages over our previously reported synthesis in that (a) the construction of the α-methylene-γ-lactone moiety is made in such a manner to avoid the formation of undesirable stereo- and regioisomers; (b) the synthesis was performed in 7 steps, starting from known octalone 2, with an overall yield of 27%.

A local approximation to the exchange-correlation effects is used in a detailed calculation of the $s$-core binding-energy splittings for the $3d$ transition elements and rare-earth series. Our approach to the many-body problem is a single-particle model based on an effective wave equation with the mass operator instead of the simpler exchange operator of Hartree-Fock theory. By treating the exchange-correlation effects (mass operator) in a form of an effective local potential in the free-electron gas, the splittings are calculated in the framework of the self-consistent-field method applied to free ions. The results are in good agreement with x-ray photoemission experimental data taken for $3d$ transition and rare-earth ionic compounds and metals.

The reaction of unsaturated alcohols with aryltellurium trihalides leads to cyclic ethers bearing an aryldihalotelluro group in the β position, in high yields. Reduction of the tellurium-halogen bond with thiourea dioxide gives the corresponding tellurides in excellent yields.

The reaction of diterpenes 1–3 and monoterpenes 9 , 10 with thallium triacetate leads stereoselectively to the tetrahydrofuran products 5–7 and 11 , 12 respectively, by 5-Endo-Trig cyclisation of the 3-alkenol system.

Additive shielding parameters for the phenylseleno group (ZPhSe-gem = 1.36; ZPhSe-cis = 0.31; ZPhSe-trans = 0.29) have been estimated. Examples of the calculation of chemical shifts for olefinic protons in vinylic selenides by means of these increments are given. A comparison with 2-pyridylseleno and methylseleno substituents has been made. The standard deviations of the Z values are 0.06 for ZPhSe-gem, 0.10 for ZPhSe-cis and 0.05 for ZPhSe-trans.

The self-consistent formulation of the variational cellular method has been developed in order to calculate the electronic structure of crystals with an arbitrary number of atoms per unit cell. Applications for silicon have been carried out. Silicon, chosen here as a test case, is treated as a face-centered cubic lattice with four “atoms” per unit cell by adding empty cells. The electronic charge density was taken muffin-tin, assuming a constant value in the interstitial region between the inscribed sphere and the Wigner–Seitz polyhedrum. The spherical symmetric electronic charge density in the inscribed sphere was obtained by adding a limited number of contributions of Brillouin zone states using the “mean value point theory” developed by Baldereschi and Chadi-Cohen. Our results are in good agreement with those obtained by other methods.

É relatado o caso de um paciente do sexo masculino, de 15 anos de idade, que apresentava dificuldade para movimentar os braços e para abrir a bôca, além de dispnéia, evoluindo lentamente há dois anos. O exame neurológico revelou hipertonia em todo o corpo, predominando em alguns grupos musculares que se achavam fortemente contraturados, obrigando o paciente a assumir atitudes anormais, impossibilitando-o, ainda, de abrir a bôca e de respirar livremente, dada a grande diminuição da expansibilidade torácica. O exame eletromiográfico revelou a presença de atividade muscular contínua, mesmo durante o repouso, caracterizada por descargas de alta freqüência, as quais persistiram após bloqueio anestésico de nervo periférico e após anestesia geral, sõmente sendo eliminados pelo curare. Com o diagnóstico de esclerodermia e de miosite, embora só a primeira dessas moléstias pudesse ser comprovada anátomo-patològicamente, o paciente foi tratado com corti-costeróides, tendo havido discreta melhora do quadro clínico, sobretudo em relação aos movimentos respiratórios e à abertura da bôca. Tendo, então, o conhecimento de dois casos semelhantes estudados por Isaacs em 1961, com o nome de síndrome da atividade contínua da fibra muscular, os quais haviam sido curados com o uso de hidantoinato de sódio, os autores empregaram esta mesma medicação, tendo verificado, após alguns dias, a diminuição acentuada da atividade anormal pelo exame eletromiográfico. The case of a 15-year-old male patient, suffering from difficulty in moving his arms and opening his mouth and dyspnea which had been slowly developing for two years, is reported. The neurologic examination revealed diffuse hypertonus, predominating in some muscle groups, compelling the patient to assume abnormal attitudes and making it impossible for him to open his mouth and to breathe freely due to a large decrease in the thoracic expansibility. The electromyographic studies showed continuous muscle activity at rest, characterized by high frequency discharges, which continued after anesthetic blocking of a peripheral nerve and after general anesthesia; these discharges were eliminated only when curare was used. Diagnosis was made of scleroderma and myositis, although only the first one could be confirmed by biopsy; the patient was treated with corticosteroids and a slight improvement was evidenced, specially in regard to breathing movements and mouth opening. Based on the good results reported by Isaacs in two similar cases, the authors used sodium hidantoinate, and thus found a marked decrease of the abnormal electric activity, proved though an electromyographic examination made some days afterwards.

Estudou-se a influência da aplicação por imersão, de retardadores de crescimento (CCC e SADH), 5 dias antes do florescimento, nas características morfológicas da panícuia da videira Vitis (labrusca x vinifera) 'Niagara Rosada'. Neste ensaio verificou-se que as concentrações de CCC aplicadas em pré-florescimento, não afetaram favoravelmente a morfologia das panículas da cultivar estudada, nas condições do ensaio. SADH na dosagem de 1000 ppm provocou, na primeira colheita, aumento no peso e comprimento da panícula, no peso das bagas, e no comprimento da ráquis, proporcionando a formação desejada de uma panícula mais alongada, nas condições estudadas. Aplicação de SADH na concentração de 250 ppm em pré-florescimento, promoveu aumento no peso e comprimento da panícula, número e peso das bagas, além do inconveniente de elevar o número de sementes. Studies were carried out to establish the effects of exogenous growth regulators on Vitis (labrusca x vinifera) 'Niagara Rosada' fruiting. The investigations were done in the Jundiaí Research Station, Agronomic Institute State of São Paulo, always using disease-free vineyards of good productivity. The morphological transformations of clusters were studied under the following aspects: weight, length and width of cluster; weight, length average and width average of berries: length average/width average ratio of berries; length and diameter of rachis; width of cluster minus berries; length and diameter of secondary rachis. The yield for the first half of the period from flowering to maturation was first determined. The same characteristics were determined at the time of maturity plus the number of berries, number of seeds, total sugars, total acid, Maturity Index and reducing sugars in samples of all treatments. The experiment was conducted in order to determine the doses that resulted in the most beneficial effects, always using applications by immersion of the inflorescence. In the experiment was realized applications of (2-chloroethyl) trimethylammonium chloride (CCC) and succinic aeid-2, 2-dimethylhydrazide (SADH) at concentrations of 50, 100, 250, 500, 1000 and 2000 ppm; CCC 500 ppm plus SADH 500 ppm and nontreated, 5 days before flowering, in 1971. The concentrations of CCC applied before flowering did not affect favorably cluster morphology under the conditions of the experiment. Application of SADH at 250 ppm before flowering increased the cluster weight and length, berries number and weight, and seed number. In the first yield treatment of 1000 ppm of SADH increased the cluster weight and lenght, berry weight and rachis lenght.

Studies were carried out to establish the effects of exogenous growth regulators on Vitis (Labrusca x vinifera) 'Niagara Rosada' fruiting. The investigations were done in the Jundiaí Research Station, Agronomic Institute State of São Paulo, always using disease-free vineyards of good productivity. The morphological transformations of clusters were studied under the following aspects: weight, length and width of cluster; number of berries; weight, length average and width average of berries; length average/width average ratio of berries; number of seeds; length and diameter of rachis; width of cluster minus berries; length and diameter of secondary rachis. That characteristics were determined at the time of maturity plus the total sugars, total acid, Maturity Index and reducing sugars in samples of all treatments. The experiment was conducted in order to determine the doses that resulted in the most beneficial effects, always using applications by immersion of the inflorescence. In 1970 the experiment consisted of applications of gibberellins and 2-hydroxymethyl-4-chlorophenoxyacetic acid treatments of 5, 10, 25, 50, 100 and 500 ppm; gibberellins 50 ppm plus 2-hydroxymethyl-4-chlorophenoxyacetic acid 50 ppm and nontreated, 11 days after flowering. The effectiveness of 100 ppm of gibberellins after flowering to increase cluster weight, berry number and weight, elongation of secondary rachis was determined. Treatment with gibberellins 50 ppm plus 2-hydroxymethyl-4-chlorophenoxyacetic acid 50 ppm increases cluster weight, berries number and weight. Gibberellins at concentration of 500 ppm stimulated berry elongation but did not benefit other characters. Application of 2-hydroxymetlhyl-4-chlorophenoxyacetic acid after flowering, at the concentrations used did not result in good results in 'Niagara Rosada' fruiting under the conditions studied. Estudou-se a influência da aplicação, por imersão, de giberelinas e auxina (ácido 2-hidroximetil 4-clorofenoxiacético), 11 dias após o florescimento, nas características morfológicas da panícula da videira Vitis (labrusca x vinifera) 'Niagara Rosada'. Neste experimento verificou-se que, aplicação de giberelinas na concentração de 100 ppm em pós-florescimento, promoveu aumento no peso da panícula, número e peso das bagas, além de alongamento da ráquila, o que contribue para a formação de panículas com distribuição das bagas mais adequada. Tratamento com giberelinas 60 ppm + ácido 2-hidroximetil 4-clorofenoxiacético 50 ppm provocou aumento no peso da panícula, número e peso das bagas, sem contudo promover uma melhor distribuição das mesmas. Giberelinas na concentração de 500 ppm causou aumento na elongação das bagas com relação ao diâmetro, porém não apresentou nenhuma outra característica superior ao controle. Aplicação do ácido 2-hidroximetil 4-clorofenoxiacético em pós-fiorescimento, nas concentrações utilizadas, não apresentou resultados favoráveis na frutificação da 'Niagara Rosada', nas condições de estudo.

A manutenção de um balanço hídrico favorável à planta é uma condição reconhecidamente necessária para assegurar a seqüência das reações metabólicas que se desenvolvem nas células vegetais. Os deficits de água¹ nas plantas poderiam ser quantitativamente avaliados a partir de determinações do teor ou do estado de energia da água dos tecidos. Neste trabalho, o potencial osmótico das hastes e folhas, o potencial da água da folha e as relações entre este e o teor relativo de água da folha foram determinados em plantas de batata (Solanum tuberosum L.) adequadamente supridas com água do solo, em condições de campo. Os resultados revelaram que os potenciais determinados variaram durante o ciclo fenológico. Assim, o potencial da água da folha foi sendo reduzido com o desenvolvimento das plantas. Após o completo desenvolvimento vegetativo, não foi possível identificar qualquer tendência definida, crescente ou decrescente. Esta variação modificou as relações entre o potencial e o teor relativo de água da folha, de tal maneira, que o potencial associado a um determinado teor relativo de água, foi sendo reduzido a medida que as plantas se desenvolveram. A par destes resultados, pode-se concluir que o potencial da água da folha não parece ser um indicador seguro da existência de déficits fisiológicos de água na planta. O conhecimento do teor relativo de água, associado ao potencial, poderia contribuir decisivamente para fornecer uma avaliação mais precisa da condição da água nos tecidos vegetais.

Introduction: Thoracoscopy is increasingly being used in the treatment of empyema. This study assesses feasibility, efficacy and safety in children. Material and methods: Clinical files of patients who underwent primary thoracoscopy for empyema between 2006 and 2014 were reviewed. Demographic, clinical and surgical data were analyzed and a comparison between the period before (period1) and after (period2) the learning curve was performed. Results: Ninety-one patients (53 males, 58%) were submitted to thoracoscopy at a median age of 4 years. There were 19 conversions to thoracotomy with a steady decrease of conversion rate until 2009 (period1) and no conversions thereafter (period2). There was no difference in any of the analyzed parameters between patients submitted to thoracoscopy alone and those requiring conversion in period1. Six cases (6.6%) needed redo-operation (five in period2) and thoracotomy was the elected approach in four. Necrotizing pneumonia was present in 60% of the reoperated cases; in other words, in period2 3 out of 9 cases with necrotizing pneumonia required reintervention (p = 0.07). Thoracotomy was avoided in sixty-eight (75%) patients (62% in period1 versus 92% in period2, p = 0.001). Discussion and conclusions: Thoracoscopic approach for empyema is feasible and safe avoiding a significant number of thoracotomies after a short learning curve. An increase of reintervention rate should be expected, but throracoscopy alone is effective in the great majority of the cases. Necrotizing pneumonia may be associated with a higher risk of reintervention, as it is a contra-indication to thoracoscopy and probably surgery. Keywords: Thoracoscopy, Empyema, Children, Conversion, Reintervention

We have developed a new synthetic approach to the α-methylene-γ-lactone moiety 4, which is present in numerous sesquiterpene natural products.

The recently proposed variational cellular method (VCM) is extended to periodic structures with one atom per unit cell. The method as outlined in this paper is applied to the calculation of the band structure of metallic lithium. The results show that the VCM leads to accurate energy levels for Li requiring a small computational effort. It is concluded that the results are sufficiently encouraging to suggest the application of the method to more complex crystals.

Synthese du compose du titre via un intermediaire cle bicyclique prepare a partir du dimethyl-4a,8 bromo-2 octahydronaphtalene et de l'acide phenylseleno-2 propionique

Large nucleic acids can be separated by reversed-phase high-performance liquid chromatography. Under our experimental conditions, the retention time depends not on the chain length but rather on the base composition and the secondary structure of the molecule. Because of the torsional strain caused by the supercoiling of the plasmid, more of its bases are accessible for interaction with the hydrophobic stationary phase. This increases the retention time of the supercoiled DNA compared to the relaxed or linear DNA. We have exploited these properties to analyze the quality of plasmid preparations. The method is more sensitive to contaminants than common electrophoretic techniques. Furthermore, we describe a convenient and rapid procedure for purifying plasmid DNA. The highly pure plasmid is biologically more active for most of the enzymatic reactions commonly used in genetic engineering.

The reaction of unsaturated alcohols with aryltellurium trihalides leads to cyclic ethers bearing an aryldihalotelluro group in the β position, in high yields. Reduction of the tellurium-halogen bond with thiourea dioxide gives the corresponding tellurides in excellent yields.

Octopus calmodulin was purified to homogeneity and shown to contain 0.1 residue each of epsilon-N-monomethyl-lysine, epsilon-N-dimethyllysine, and epsilon-N-trimethyllysine/mol. With the exception of this partial methylation and of a single tyrosyl residue, it shared all the characteristic properties of mammalian calmodulin in terms of molecular weight, amino acid composition, electrophoretic behavior in the presence or absence of Ca2+ ions, and activation of calcium/calmodulin-dependent myosin light chain kinase. In fact, Octopus calmodulin proved to be slightly more effective than ram testis calmodulin in activating both skeletal and smooth muscle myosin light chain kinases in the presence of Ca2+. This provides conclusive evidence that (a) stoichiometric trimethylation of lysine 115 is not required for enzyme activation, and (b) the inability of troponin C to activate myosin light chain kinase (Walsh, M. P., Vallet, B., Cavadore, J. C., and Demaille, J. G.

A weak ion-exchange column (PVDI 4000-5) was used to purify oligonucleotides of relatively large size. The purification of polynucleotides was very rapid, they were separated according to size and retained all their properties relevant to genetic engineering experiments.

4 histochemical methods for demonstration of protein acid groups: Nihydrin-Schiff, Millon, DDD and DMAB-nitrite were applied in sections of rat pancreas fixed in the following fixatives: 10% formalin, 10% formalin in saline, ZENKER and GENDRE, and treated with the following decalcifying solutions: 5% nitric acid, 5% trichloroacetic acid, 33% formic acid, 5% EDTA pH=7.0 JENKINS, GREEP and citrate buffer pH=4.5. The colour intensity of each reaction was measured photometrically over the zymogen granules region of the acinar cells, using a Zeiss histophotometer, and compared with controls, i.e., fixed tissue which have not been treated with decalcifying solutions. The results have shown that for each method there is more than one combination fixative-decalcifying solution which gives results similar to those of the control.

The lactones and cyclic ethers produced in the tellurocyclofunctionalization of unsaturated car☐ylic acids and alcohols are efficiently detellurated by tri-n-butyl tin hydride. Trapping of the intermediate free radicals with methyl acrylate leads to the corresponding adducts in moderate to good yields.

The protein inhibitor of adenosine 3':5 monophosphate-dependent protein-kinases has been purified from rabbit skeletal muscle by affinity chromatography on Sepharose-bound catalytic subunit of the kinase (Demaille et al. (1977) Biochemistry 16, 3080-3086). The inhibitory material can be separated into three species A, B and C either by polyacrylamide gel electrophoresis or by anion-exchange on DEAE-cellulose. However, the isoinhibitors display the same molecular weight and isoelectric point, and the same absence of acid-stable covalently bound phosphate. Their amino acid compositions are strikingly similar and their NH2-terminus are blocked. Also, their COOH-terminus appear to be very close to one another when studied by carboxypeptidase Y digestion. Their major difference lies in their inhibitory properties which are significantly weaker in inhibitor C (Ki = 0.87 nM) than in A and B (Ki = 0.18 and 0.23 nM, respectively). This is the first report on the existence of various forms of the protein-kinase inhibitor that exhibit different inhibitory properties and may play a role in the regulation of the protein-kinase system.

According previous studies about longevity in maize by ACCORSI e ADÂMOLI DE BARROS, (1961) the authors presents in this paper the results of work on longevity of seedlings of beans. Seeds were separated in three groups according their weight, as followings: small 80-120 mg; medium 130-140 mg and big 150-200 mg. The sowing of the seeds was made in pure sand and the seedlings were distributed in distil. water and in complete solution of Arnon and Hoagland. Each treatment was made in two replications with eight seedlings by treatment. At present time the following conclusions can be related: 1.°) - Eight days after germination, the cotiledones of all the seedlings started to fell down, fourteen days after, all cotiledones had fell down. 2.°) - Fifteen days after germination, the seedlings in nutritive solution showed better development than those in distil. water. Table I e II gives results. 3.°) - All seedlings in distil. water showed symptoms of N, Ca, Fe deficiencies. 4.°) - Twenty nine days after germination the seedlings in distil. water manifested exhaust trace, by falling of the leaves and death of some plants although the aplicai buds keep green. 5.°) - After thirty-one days the plants in nutritives solution was in better condition than those in distil. water, although some alteration aboved mentioned was observed. The causes of this alteration are being studied. 6.°) - In many plants in complet solution the seminal leaves showed clorosis initial and some with necrosis, although apical buds keeps in ativity. 7.°) - Symptoms of clorosis and necrosis in diferents stages were observed in all leaflet; these symptoms were more strong in the groups of little seed and medium seeds.

With a view to contribute to the understanding the surface effects on optical properties process, and its hole in the electronic properties of the nanoparticles, CdS based nanoparticles are characterised by different experimental techniques and the experimental results compared to density functional theory calculations. Our results indicate that cubic CdS nanoparticles present a strong structural deformation, hexagonal reconstructed structures preserve their lattice behaviour. Both cubic and hexagonal CdS nanoparticles are S-terminated after relaxation, even when mildly Cd-rich nanoparticles are considered. A broad peak observed in our PL measurements is interpreted as an experimental evidence of the surface related peak observed around 1.8 eV in our calculated DOS for the hexagonal relaxed structure.