聚3-羟基丁酸酯(PHB)生物降解过程的研究

利用DS970 1菌株对聚 3 羟基丁酸酯 (PHB)膜进行降解 ,对降解到不同程度的PHB膜采用扫描电子显微镜观察其表面形态结构的变化 ,并对其降解产物进行分析测定 .结果表明 ,PHB的生物降解首先发生在PHB表面的非晶部分 ,随后结晶部分开始降解 ,并且降解首先发生在球晶的中心部分 .DS970 1菌株所产生的PHB解聚酶主要降解PHB的第二个酯键 ,降解产物为二聚体.

Miscibility and crystallization of PHB PMA blends

The miscibility, crystallization behavior and morphological structure of PHB/PMA blends have been studied by the differential scanning calorimeter (DSC) and polarized optical microscopy (POM). The chemical repeat units of the two components of the blend are isomers. The results indicate that PHB and PMA are miscible in the melt. The addition of PMA into PHB results in a depression in the spherulite growth rate of PHB. With increasing PMA content in the blends, the texture of PHB spherulite becomes more open.

Study on the UCST and LCST in PHB/PBHE-solvent system

Upper and lower critical solution temperature (UCST and LCST) behaviours have been examined for solution of PHB/PBHE blends in chloroform and chlorobenzene. Polymer-Solvent systems prepared with various solvents and concentrations were found to possess UCST and LCST characteristics. PHB/PBHE solution in chloroform displayed greater miscibility temperature region than that of the blend in chlorobenzene, but the relative tendency of both UCST and LCST were similar.

PHB／PVPh共混体系的相容性及分子间的特殊相互作用

ＰＨＢ／ＰＶＰｈ共混体系的相容性及分子间的特殊相互作用邢佩祥，董丽松，冯汉桥，安玉贤，庄宇钢，冯之榴（中国科学院长春应用化学研究所高分子物理开放实验室，长春，１３００２２；中国科学院武汉物理研究所波谱与原子分子实验室）关键词氢键，相容性，聚（β－羟基...

PHB／PPO共混体系的相容性和结晶

采用溶液共混方法对聚β－羟基丁酸酯（ＰＨＢ）／聚氧化丙烯（ＰＰＯ）共混体系的相容性和结晶行为进行了研究。ＤＳＣ、ＰＯＭ、ＷＡＸＤ等实验结果表明，该体系是不相容体系。但在特殊的组成比下有相容的第三相存在。ＰＰＯ对ＰＨＢ的结晶结构无影响，但对ＰＨＢ的结晶速率和结晶完整性有很大作用。

Assessing initial embodied energy in building structures using LCA methodology

The considerable amount of energy consumed on Earth is a major cause for not achieving sustainable development. Buildings are responsible for the highest worldwide energy consumption, nearly 40%. Strong efforts have been made in what concerns the reduction of buildings operational energy (heating, hot water, ventilation, electricity), since operational energy is so far the highest energy component in a building life cycle. However, as operational energy is being reduced the embodied energy increases. One of the building elements responsible for higher embodied energy consumption is the building structural system. Therefore, the present work is going to study part of embodied energy (initial embodied energy) in building structures using a life cycle assessment methodology, in order to contribute for a greater understanding of embodied energy in buildings structural systems. Initial embodied energy is estimated for a building structure by varying the span and the structural material type. The results are analysed and compared for different stages, and some conclusions are drawn. At the end of this work it was possible to conclude that the building span does not have considerable influence in embodied energy consumption of building structures. However, the structural material type has influence in the overall energetic performance. In fact, with this research it was possible that building structure that requires more initial embodied energy is the steel structure; then the glued laminated timber structure; and finally the concrete structure.

Biocompatible polyhydroxybutyrate (PHB) production by marine Vibrio azureus BTKB33 under submerged fermentation

Polyhydroxybutyrate (PHB) is known to have applications as medical implants and drug delivery carriers and is consequently in high demand. In the present study the possibilities of harnessing potential PHB-producing vibrios from marine sediments as a new source of PHB was investigated since marine environments are underexplored. Screening of polyhydroxyalkanoate (PHA)-producing vibrios from marine sediments was performed using a fluorescent plate assay followed by spectrophotometric analysis of liquid cultures. Out of 828 isolates, Vibrio sp. BTKB33 showed maximum PHA production of 0.21 g/L and PHA content of 193.33 mg/g of CDW. The strain was identified as Vibrio azureus based on phenotypic characterization and partial 16S rDNA sequence analysis. The strain also produced several industrial enzymes: amylase, caseinase, lipase, gelatinase, and DNase. The FTIR analysis of extracted PHA and its comparison with standard PHB indicated that the accumulated PHA is PHB. Bioprocess development studies for enhancing PHA production were carried out under submerged fermentation conditions. Optimal submerged fermentation conditions for enhanced intracellular accumulation of PHA production were found to be 35 °C, pH −7, 1.5 % NaCl concentration, agitation at 120 rpm, 12 h of inoculum age, 2.5 % initial inoculum concentration, and 36 h incubation along with supplementation of magnesium sulphate, glucose, and ammonium chloride. The PHA production after optimization was found to be increased to 0.48 g/L and PHA content to426.88 mg/g of CDW, indicating a 2.28-fold increase in production. Results indicated that V. azureus BTKB33 has potential for industrial production of PHB.

Investigations on the structural and operational changes of Ring Seine Fishing Systems of Kerala and its Life Cycle Assessment (lCA)

The study covers theFishing capture technology innovation includes the catching of aquatic animal, using any kind of gear techniques, operated from a vessel. Utilization of fishing techniques varies, depending upon the type of fisheries, and can go from a basic and little hook connected to a line to huge and complex mid water trawls or seines operated by large fishing vessels.The size and autonomy of a fishing vessel is largely determined by its ability to handle, process and store fish in good condition on board, and thus these two characteristics have been greatly influenced by the introduction and utilization of ice and refrigeration machinery. Other technological developments especially hydraulic hauling machinery, fish finding electronics and synthetic twines have also had a major impact on the efficiency and profitability of fishing vessels.A wide variety of fishing gears and practices ranging from small-scale artisanal to advanced mechanised systems are used for fish capture in Kerala. Most important among these fishing gears are trawls, seines, lines, gillnets and entangling nets and traps The modern sector was introduced in 1953 at Neendakara, Shakthikulangara region under the initiative of Indo-Norwegian project (INP). The novel facilities introduced in fishing industry by Indo- Norwegian project accordingly are mechanically operated new boats with new fishing nets. Soon after mechanization, motorization programme gained momentum in Kerala especially in Alleppey, Ernakulam and Kollam districts.

Guía de práctica clínica sobre diagnóstico y manejo de las rupturas agudas del ligamento cruzado anterior (LCA)

Desarrollo y redacción de una guía basada en la mejor evidencia disponible sobre el diagnóstico y manejo de la ruptura aguda del ligamento cruzado anterior (LCA) para asistir a la toma de decisiones para controlar la variabilidad en los procesos clínicos de diagnóstico y manejo de dicha patología. Se definió el grupo de desarrollo de la guía (GDG) y de acuerdo con la metodología desarrollada en el Centro de Estudios del Hospital según convocatoria del Ministerio de Salud, se cumplieron las siguientes etapas : Priorización, definición de foco y alcance, formulación de las preguntas clínicas relevantes al estado del arte y puntos de controversia actual en el tema a tratar (Metodología PECOT), revisión sistemática de la literatura, síntesis de la evidencia, evaluación y graduación de acuerdo con la metodología "GRADE" y las platillas propuestas por SIGN. Por consenso se definieron las recomendaciones de acuerdo con la metodología GRADE. Se presenta una Guía de Práctica Clínica (GPC), que responde las preguntas: enfoque de hemartrosis, indicaciones quirúrgicas, terapia física preoperatoria, profilaxis antitrombótica, tipo de injerto, anestésicos intrarticulares, lesiones asociadas, posición del túnel femoral, reconstrucción de uno contra dos haces. De acuerdo con la evidencia encontrada se formulan doce recomendaciones ajustadas al nivel de evidencia. La presente GPC corresponde a un piloto de una metodología para desarrollo de GPC aprobabda para uso a nivel nacional y al primer producto sobre este tema en la literatura encontrada.

PHB Biosynthesis in Catabolite Repression Mutant of Burkholderia sacchari

Due to the effect of catabolite repression, sugar mixtures cannot be metabolized in a rapid and efficient way implicating in lower productivity in bioprocesses using lignocellulosic hydrolysates. In gram-negative bacteria, this mechanism is mediated by the phosphotransferase system (PTS), which concomitantly internalizes and phosphorylates sugars. In this study, we isolated a UV mutant of Burkholderia sacchari, called LFM828, which transports hexoses and pentoses by a non-PTS uptake system. This mutant presented released glucose catabolite repression over the pentoses. In mixtures of glucose, xylose, and arabinose, specific growth rates and the specific sugar consumption rates were, respectively, 10 and 23% higher in LFM828, resulting in a reduced time to exhaust all sugars in the medium. However, in polyhydroxybutyrate (PHB) biosynthesis experiments it was necessary the supplementation of yeast extract to maintain higher values of growth rate and sugar consumption rate. The deficient growth in mineral medium was partially recovered by replacing the ammonium nitrogen source by glutamate. It was demonstrated that the ammonium metabolism is not defective in LFM828, differently from ammonium, glutamate can also be used as carbon and energy allowing an improvement on the carbohydrates utilization for PHB production in LFM828. In contrast, higher rates of ammonia consumption and CO(2) production in LFM828 indicate altered fluxes through the central metabolism in LFM828 and the parental. In conclusion, PTS plays an important role in cell physiology and the elimination of its components has a significant impact on catabolite repression, carbon flux distribution, and PHB biosynthesis in B. sacchari.

Correlação entre torque, equlíbrio e função do joelho após reconstrução do LCA

Background: Several studies emphasize the importance of assessing the knee function after anterior cruciate ligament (ACL) reconstruction. The influence of several variables on the function of these patients has been analyzed, but there is no consensus in the science literature. Purpose: To evaluate the correlation between the torque and balance on the knee function after ACL reconstruction. Methods: 23 males patients with ACL reconstruction were tested. The procedures of the study included analysis of concentric peak torque at 60o/s and 180o/s of quadriceps femoris and hamstring muscle with a isokinetic dynamometer. The balance in single-limb stance was measured with stabilometry. The functional performance were performed by two hop tests. To estimate the subjective function of the patients was applied Lysholm Knee Scoring Scale and a Global Rating scale. Results: The analysis of data showed a moderate positive correlation between knee extensor torque and functional performance tests (r= 0,48; p=0,02). A moderate negative correlation was found between the two variables of the stabilometry center of pressure and average speed of centre of pressure and the Global Rating scale (r = -0.4, p = 0,04 and r = -0,49, p = 0 ,02, respectively). No correlation was found between peak torque and balance in single-limb stance. Conclusion: The results of the present study suggest that knee extensor strength and postural balance have some influence on knee function in patients after ACL reconstruction

Piezo and Dielectric Properties of PHB-PZT Composite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)