cis-acting sequences and trans-acting factors in the localization of mRNA for mitochondrial ribosomal proteins

mRNA localization is a conserved post-transcriptional process crucial for a variety of systems. Although several mechanisms have been identified, emerging evidence suggests that most transcripts reach the protein functional site by moving along cytoskeleton elements. We demonstrated previously that mRNA for mitochondrial ribosomal proteins are asymmetrically distributed in the cytoplasm, and that localization in the proximity of mitochondria is mediated by the 3′-UTR. Here we show by biochemical analysis that these mRNA transcripts are associated with the cytoskeleton through the microtubule network. Cytoskeleton association is functional for their intracellular localization near the mitochondrion, and the 3′-UTR is involved in this cytoskeleton-dependent localization. To identify the minimal elements required for localization, we generated DNA constructs containing, downstream from the GFP gene, deletion mutants of mitochondrial ribosomal protein S12 3′-UTR, and expressed them in HeLa cells. RT-PCR analysis showed that the localization signals responsible for mRNA localization are located in the first 154 nucleotides. RNA pulldown assays, mass spectrometry, and RNP immunoprecipitation assay experiments, demonstrated that mitochondrial ribosomal protein S12 3′-UTR interacts specifically with TRAP1 (tumor necrosis factor receptor-associated protein1), hnRNPM4 (heterogeneous nuclear ribonucleoprotein M4), Hsp70 and Hsp60 (heat shock proteins 70 and 60), and α-tubulin in vitro and in vivo

The structure of trailing vortices generated by model rotor blades

Hot-wire anemometry to analyze the structure and geometry of rotary wing trailing vortices is studied. Tests cover a range of aspect ratios and blade twist. For all configurations, measured vortex strength correlates well with maximum blade-bound circulation. Measurements of wake geometry are in agreement with classical data for high-aspect ratios. The detailed vortex structure is similar to that found for fixed wings and consists of four well defined regions--a viscous core, a turbulent mixing region, a merging region, and an inviscid outer region. A single set of empirical formulas for the entire set of test data is described

Surgical approaches to adenocarcinoma of the gastroesophageal junction: the Siewert II conundrum.

BACKGROUND: The Siewert classification system for gastroesophageal junction adenocarcinoma has provided morphological and topographical information to help guide surgical decision-making. Evidence has shown that Siewert I and III tumors are distinct entities with differing epidemiologic and histologic characteristics and distinct patterns of disease progression, requiring different treatment. Siewert II tumors share some of the characteristics of type I and III lesions, and the surgical approach is not universally agreed upon. Appropriate surgical options include transthoracic esophagogastrectomy, transhiatal esophagectomy, and transabdominal extended total gastrectomy. PURPOSE: A review of the available evidence of the surgical management of Siewert II tumors is presented. CONCLUSIONS: Careful review of the data appear to support the fact that a satisfactory oncologic resection can be achieved via a transabdominal extended total gastrectomy with a slight advantage in terms of perioperative complications, and overall postoperative quality of life. Overall and disease-free survival compares favorably to the transthoracic approach. These results can be achieved with careful selection of patients balancing more than just the Siewert type in the decision-making but considering also preoperative T and N stages, histological type (diffuse type requiring longer margins that are not always achievable via gastrectomy), and the presence of Barrett\u27s esophagus

Synchronous operation of high frequency inductive power transfer systems through injection locking

High frequency inductive power transfer systems can be designed for operation with high tolerance to misalignment and large air-gaps, making it possible to operate in highly dynamic environments. Most examples in the literature use a single active transmitter and a single passive receiver (active-passive approach). Such systems are limited to unidirectional power flow and are susceptible to detuning of the transmitter due to changes of reflected reactance stemming from diode non-linearities. This also limits the range of coupling over which the system can be operated efficiently. Therefore there is significant potential for expanding the range of applications of inductive power transfer systems by moving to an active-active configuration. This will enable bidirectional power flow, power routing through several nodes and on-the-fly retuning to eliminate reflected reactances. One of the greatest challenges in achieving an active secondary in an IPT system is obtaining a stable frequency and phase reference for the synchronous rectifier/transceiver with respect to the transmitter coil current and hence magnetic field. Various methods for synchronisation have been proposed in the literature, but they either require a separate, out of band communication link, or are difficult to scale to MHz operation. This paper describes an alternative to the existing solutions, using an injection locked oscillator to provide optimal phase tracking. A series of candidate feedback configurations are also proposed to provide high system resilience. In this work the basic principles of injection locking are described as applied to synchronous IPT transceivers and experimental results are presented demonstrating its application to a bidirectional back-to-back Class-EF configuration operating at 13.56 MHz, with coupling factors ranging from 1.9 % to 8.4 % and power levels of up to 25 W

Los comportamientos relativos a la salud y la calidad del sueño en los adolescentes portugueses: el efecto moderador de la edad y del sexo

Adolescence is marked by changes such as sleep and health behaviors. This study analyzed the relationships and differences on excessive daytime sleepiness, anxiety and depression symptoms, sleep habits, family sleep behaviors, sleep quality and health behaviors in adolescents including the moderating effect of adolescents’ age and gender. Method: The sample included 272 adolescents, 58% being female. Results: Girls and older adolescents reported worse sleep quality. Older adolescents reported healthier behaviors. Female gender, having a family member with sleep quality problems, coffee intake, anxiety and depression symptoms, daytime sleepiness, and family sleep behaviors contributed to worse sleep quality. Father’s alcohol consumption, anxiety and depression symptoms and family sleep behaviors contributed to adolescents’ sleep habits. Being a girl and an older adolescent were moderators in the relationship between the presence of excessive daytime sleepiness and worse sleep quality. Conclusions: Findings highlight the importance of health promotion programs regarding sleep quality.La adolescencia está marcada por los cambios en el sueño y comportamientos referidos a la salud. Este estudio analizó las relaciones y diferencias en la somnolencia diurna excesiva, los síntomas de ansiedad y depresión, los hábitos de sueño, los comportamientos de sueño familiares, la calidad del sueño, los comportamientos de salud en adolescentes, incluido el efecto moderador de la edad y el sexo de los adolescentes. Método: La muestra de este estudio estaba compuesta por 272 adolescentes, siendo el 58% de sexo femenino. Resultados: Las niñas y los adolescentes mayores indicaron una peor calidad del sueño. Los adolescentes mayores manifestaron comportamientos más saludables. Ser de sexo femenino, tener un familiar con problemas de sueño, consumir café, tener síntomas de ansiedad y depresión, así como somnolencia diurna y conductas de sueño familiares se asocian con una peor calidad del sueño. El consumo de alcohol del padre, los síntomas de ansiedad y depresión y las conductas de sueño familiares se asocian con los hábitos de sueño de los adolescentes. Ser niña y adolescente de mayor edad modera la relación entre la presencia de somnolencia diurna excesiva y peor calidad del sueño. Conclusiones: Los resultados resaltan la importancia de los programas de promoción de la salud en relación con la calidad del sueño