Hijacked then lost in translation:the plight of the recombinant host cell in membrane protein structural biology projects

Membrane protein structural biology is critically dependent upon the supply of high-quality protein. Over the last few years, the value of crystallising biochemically characterised, recombinant targets that incorporate stabilising mutations has been established. Nonetheless, obtaining sufficient yields of many recombinant membrane proteins is still a major challenge. Solutions are now emerging based on an improved understanding of recombinant host cells; as a 'cell factory' each cell is tasked with managing limited resources to simultaneously balance its own growth demands with those imposed by an expression plasmid. This review examines emerging insights into the role of translation and protein folding in defining high-yielding recombinant membrane protein production in a range of host cells.

Model and performance of a no-reference quality assessment metric for video streaming

Video streaming via Transmission Control Protocol (TCP) networks has become a popular and highly demanded service, but its quality assessment in both objective and subjective terms has not been properly addressed. In this paper, based on statistical analysis a full analytic model of a no-reference objective metric, namely pause intensity (PI), for video quality assessment is presented. The model characterizes the video playout buffer behavior in connection with the network performance (throughput) and the video playout rate. This allows for instant quality measurement and control without requiring a reference video. PI specifically addresses the need for assessing the quality issue in terms of the continuity in the playout of TCP streaming videos, which cannot be properly measured by other objective metrics such as peak signal-to-noise-ratio, structural similarity, and buffer underrun or pause frequency. The performance of the analytical model is rigidly verified by simulation results and subjective tests using a range of video clips. It is demonstrated that PI is closely correlated with viewers' opinion scores regardless of the vastly different composition of individual elements, such as pause duration and pause frequency which jointly constitute this new quality metric. It is also shown that the correlation performance of PI is consistent and content independent. © 2013 IEEE.

Impact of severity and type of depression on quality of life in cases identified in the community

BACKGROUND: The impact of different levels of depression severity on quality of life (QoL) is not well studied, particularly regarding ICD-10 criteria. The ICD classification of depressive episodes in three levels of severity is also controversial and the less severe category, mild, has been considered as unnecessary and not clearly distinguishable from non-clinical states. The present work aimed to test the relationship between depression severity according to ICD-10 criteria and several dimensions of functioning as assessed by Medical Outcome Study (MOS) 36-item Short Form general health survey (SF-36) at the population level. METHOD: A sample of 551 participants from the second phase of the Outcome of Depression International Network (ODIN) study (228 controls without depression and 313 persons fulfilling ICD criteria for depressive episode) was selected for a further assessment of several variables, including QoL related to physical and mental health as measured with the SF-36. RESULTS: Statistically significant differences between controls and the depression group were found in both physical and mental markers of health, regardless of the level of depression severity; however, there were very few differences in QoL between levels of depression as defined by ICD-10. Regardless of the presence of depression, disability, widowed status, being a woman and older age were associated with worse QoL in a structural equation analysis with covariates. Likewise, there were no differences according to the type of depression (single-episode versus recurrent). CONCLUSIONS: These results cast doubt on the adequacy of the current ICD classification of depression in three levels of severity.

Az autóipar szerkezeti átrendeződése – Vállalati stratégiák és a válság hatásai (Structural change in the automotive industry – corporate strategies and the impact of the crisis)

Az írás a globális értékláncok élén álló autóipari cégek világgazdasági válságra adott reakcióit foglalja össze. Megállapítja, hogy a válságnak messze nincs vége: az iparág globális átrendeződése folytatódik. A globális értékláncokba sikeresen betagozódott közép-európai autóipari klaszter ezeknek a folyamatoknak mindmáig nyertese volt. Számolni kell azonban azzal, hogy továbbra is sok a technológiai és a piaci bizonytalanság: az új szereplők belépése, új üzleti modellek elterjedése hosszabb távon felboríthatja a jelenlegi status quo-t, és veszélyeztetheti a hagyományos autóipari befektetőiket munkabér-alapú versenyképességgel megtartani próbáló közép- és kelet-európai országok pozícióit. Az autóipari működő tőkét fogadó közép-kelet-európai országok számára hosszabb távon veszélyt jelenthet az autóipari üzleti modellek átalakulása, a gyártás teljes kiszervezése komplex gyártási szolgáltatást vállaló cégekhez, mivel ez esetben az értéklánc vezető vállalatai bezárhatják a régióban működő gyártóbázisaikat. Az értékláncok élén álló globális cégek „menekülés a minőségbe” stratégiája helyi szinten is követhető, követendő, a működő tőkét fogadó országok versenyképessége kizárólag a helyi leányvállalatok állandó „feljebb lépésével” tartható fenn. ______ This paper summarizes lead firms’ reactions to crisis in global automotive value chains. The paper advances five theses. Author argues that crisis is not over yet, the global restructuring of the industry continues. Actors in the CEE automotive cluster have successfully become integrated into global value chains and have thereby been the winners of past restructuring processes. Nevertheless, technological and market uncertainties prevail: entry of new economic actors and the diffusion of new business models may, in the long run, disrupt the current status quo and jeopardise the world economic position of CEE countries that have been relying solely on their labour cost advantages to sustain direct investment inflows in their automotive industries. In the long run the automotive industries of Central and Eastern European (CEE) economies may become threatened by the transformation of the prevailing automotive business model, the outsourcing of manufacturing and related support activities to complex manufacturing services providers, which could lead to the closure of lead firms’ manufacturing facilities in CEE. Lead firms’ increased focus on high quality high value adding activities strategy can and should be followed by local subsidiaries through a continuous strive for upgrading.

Effect of child care subsidies on price and quality of care for low -income families

This dissertation examines the effect of regulations, resource and referral agencies, and subsidies on price and quality of care in child care centers. This research is based on a carefully developed conceptual framework that incorporates the factors affecting the demand and supply of child care. The first step in developing this framework is sketching out the structural equations. The structural equations help us understand the underlying behavior of individuals and firms making a decision. The exogenous variables are vector of attributes relating to family characteristics, child characteristics, regulations, subsidy, community characteristics and prices of inputs. Based on the structural equations, reduced form equations are estimated to find the effect of each of the exogenous variables on each of the endogenous variables. Reduced form equations help us answer public policy questions. The sample for this study is from the 1990 Profile of Child Care Settings (PCCS) data in which 2,089 center based programs were interviewed.^ Child/Staff Ratio (Group Level). Results indicate that among subsidies, only the state subsidy per child in poverty has a significant effect on the child/staff ratio at the group level. Presence of resource and referral agencies also increase the child/staff ratio at the group level. Also when the maximum center group size regulation for 25-36 months becomes more stringent, the child/staff ratio at the group level decreases.^ Child/Staff Ratio (Center Level). When the regulations for the maximum child/staff ratio for age groups 13-24 months and 37-60 months become lax, the child/staff ratio for the center increases. As the regulation for maximum group size for infants becomes stringent, the child/staff ratio decreases. An interesting finding is that as the regulations for maximum group size for age groups 13-24 months and 25-36 months become stringent, the child/staff ratio for the center increases. Another significant finding is that when a center is located in a rural area the child/staff ratio is significantly lower.^ Center Weighted Average Hourly Fees. Maximum group size regulations for age groups 25-36 months and 37-60 months have a negative effect on center hourly fee. Maximum child staff regulations for age groups 13-24 months and 37-60 months have a negative effect on center hourly fee. Maximum child staff regulations for age groups 0-12 months and 25-36 months have a positive effect on center hourly fee. Findings also indicate that the center average hourly price is lower when there is a resource and referral agency present. Cost adjusted prekindergarten funds and JOBS child care subsidies have a negative effect on average hourly fee. Cost adjusted social services block grant and state subsidy per child in poverty have a positive effect on the average hourly price. A major finding of this dissertation is the interaction of subsidy and regulatory variables.^ Another major finding is that child/staff ratio at the group level is lower when there is an interaction between geographic location and nature of center sponsorship. ^

Effect of child care subsidies on price and quality of care for low -income families

This dissertation examines the effect of regulations, resource and referral agencies, and subsidies on price and quality of care in child care centers. This research is based on a carefully developed conceptual framework that incorporates the factors affecting the demand and supply of child care. The first step in developing this framework is sketching out the structural equations. The structural equations help us understand the underlying behavior of individuals and firms making a decision. The exogenous variables are vector of attributes relating to family characteristics, child characteristics, regulations, subsidy, community characteristics and prices of inputs. Based on the structural equations, reduced form equations are estimated to find the effect of each of the exogenous variables on each of the endogenous variables. Reduced form equations help us answer public policy questions. The sample for this study is from the 1990 Profile of Child Care Settings (PCCS) data in which 2,089 center based programs were interviewed. Child/Staff Ratio (Group Level): Results indicate that among subsidies, only the state subsidy per child in poverty has a significant effect on the child/staff ratio at the group level. Presence of resource and referral agencies also increase the child/staff ratio at the group level. Also when the maximum center group size regulation for 25-36 months becomes more stringent, the child/staff ratio at the group level decreases. Child/Staff Ratio (Center Level): When the regulations for the maximum child/staff ratio for age groups 13-24 months and 37-60 months become lax, the child/staff ratio for the center increases. As the regulation for maximum group size for infants becomes stringent, the child/staff ratio decreases. An interesting finding is that as the regulations for maximum group size for age groups 13-24 months and 25-36 months become stringent, the child/staff ratio for the center increases. Another significant finding is that when a center is located in a rural area the child/staff ratio is significantly lower. Center Weighted Average Hourly Fees: Maximum group size regulations for age groups 25-36 months and 37-60 months have a negative effect on center hourly fee. Maximum child staff regulations for age groups 13-24 months and 37-60 months have a negative effect on center hourly fee. Maximum child staff regulations for age groups 0-12 months and 25-36 months have a positive effect on center hourly fee. Findings also indicate that the center average hourly price is lower when there is a resource and referral agency present. Cost adjusted prekindergarten funds and JOBS child care subsidies have a negative effect on average hourly fee. Cost adjusted social services block grant and state subsidy per child in poverty have a positive effect on the average hourly price. A major finding of this dissertation is the interaction of subsidy and regulatory variables. Another major finding is that child/staff ratio at the group level is lower when there is an interaction between geographic location and nature of center sponsorship.

Structural and Functional Characterization of the Human Tribbles Homologue 2 Pseudokinase

The Tribbles Homologues are a family of three eukaryotic pseudokinases (Trb1, Trb2, Trb3) that act as allosteric inhibitors and regulatory scaffold sites in pathways governing adipogenesis, cell proliferation and insulin signaling. The Tribbles Homologues have the same overall tertiary structure of the eukaryotic protein kinase domain, but lack multiple residues necessary to catalysis in the nucleotide-binding P-loop and the Mg2+-coordinating DFG motif. Trb1 has been shown conclusively to be incapable of binding ATP, whereas a recent study presents evidence that Trb2 autophosphorylates independently of Mg2+ in vitro. This finding is surprising given the high degree of sequence similarity between the two proteins (71%), and suggests unique nucleotide binding and phosphotransfer mechanisms. The goal of this project was to investigate whether Trb2 possesses kinase activity or not and determine its structural basis. A method for the high-yield recombinant expression and purification of stable Trb2 was developed. Trb2 nucleotide binding and autophosphorylation could not be detected across multiple experimental approaches, including thermal shift assays, MANT-ATP fluorescence, radiolabeled phosphate incorporation, and nonspecific ATPase activity assays. Further characterization also revealed that Trb2 forms homomultimers with possible functional consequences, and extensive crystallization screening has yielded multiple promising conditions that could produce diffraction-quality crystals with further optimization. This project explores the difficulties in functionally characterizing putatively active pseudokinases, and proposes a structural basis for the conserved pseudokinase features of the Tribbles homologues.

Investigations on the structural, optical and magnetic properties of nanostructured cerium oxide in pure and doped forms and its polymer nanocomposites

In recent years, nanoscience and nanotechnology has emerged as one of the most important and exciting frontier areas of research interest in almost all fields of science and technology. This technology provides the path of many breakthrough changes in the near future in many areas of advanced technological applications. Nanotechnology is an interdisciplinary area of research and development. The advent of nanotechnology in the modern times and the beginning of its systematic study can be thought of to have begun with a lecture by the famous physicist Richard Feynman. In 1960 he presented a visionary and prophetic lecture at the meeting of the American Physical Society entitled “there is plenty of room at the bottom” where he speculated on the possibility and potential of nanosized materials. Synthesis of nanomaterials and nanostructures are the essential aspects of nanotechnology. Studies on new physical properties and applications of nanomaterials are possible only when materials are made available with desired size, morphology, crystal structure and chemical composition. Cerium oxide (ceria) is one of the important functional materials with high mechanical strength, thermal stability, excellent optical properties, appreciable oxygen ion conductivity and oxygen storage capacity. Ceria finds a variety of applications in mechanical polishing of microelectronic devices, as catalysts for three-way automatic exhaust systems and as additives in ceramics and phosphors. The doped ceria usually has enhanced catalytic and electrical properties, which depend on a series of factors such as the particle size, the structural characteristics, morphology etc. Ceria based solid solutions have been widely identified as promising electrolytes for intermediate temperature solid oxide fuel cells (SOFC). The success of many promising device technologies depends on the suitable powder synthesis techniques. The challenge for introducing new nanopowder synthesis techniques is to preserve high material quality while attaining the desired composition. The method adopted should give reproducible powder properties, high yield and must be time and energy effective. The use of a variety of new materials in many technological applications has been realized through the use of thin films of these materials. Thus the development of any new material will have good application potential if it can be deposited in thin film form with the same properties. The advantageous properties of thin films include the possibility of tailoring the properties according to film thickness, small mass of the materials involved and high surface to volume ratio. The synthesis of polymer nanocomposites is an integral aspect of polymer nanotechnology. By inserting the nanometric inorganic compounds, the properties of polymers can be improved and this has a lot of applications depending upon the inorganic filler material present in the polymer.

Structural Time Series Modeling: an Application to Environmental Variables

A structural time series model is one which is set up in terms of components which have a direct interpretation. In this paper, the discussion focuses on the dynamic modeling procedure based on the state space approach (associated to the Kalman filter), in the context of surface water quality monitoring, in order to analyze and evaluate the temporal evolution of the environmental variables, and thus identify trends or possible changes in water quality (change point detection). The approach is applied to environmental time series: time series of surface water quality variables in a river basin. The statistical modeling procedure is applied to monthly values of physico- chemical variables measured in a network of 8 water monitoring sites over a 15-year period (1999-2014) in the River Ave hydrological basin located in the Northwest region of Portugal.

Seed layer technique for high quality epitaxial manganite films

We introduce an innovative approach to the simultaneous control of growth mode and magnetotransport properties of manganite thin films, based on an easy-to-implement film/substrate interface engineering. The deposition of a manganite seed layer and the optimization of the substrate temperature allows a persistent bi-dimensional epitaxy and robust ferromagnetic properties at the same time. Structural measurements confirm that in such interface-engineered films, the optimal properties are related to improved epitaxy. A new growth scenario is envisaged, compatible with a shift from heteroepitaxy towards pseudo-homoepitaxy. Relevant growth parameters such as formation energy, roughening temperature, strain profile and chemical states are derived.

Children's mental representations of attachment: associations with attachment security and parent-child narrative quality

The goal of this study was to examine the antecedents and correlates of children’s mental representations of attachment at 5 years (Attachment Story Completion Task, Bretherton, Ridgeway, & Cassidy, 1990; MacArthur Story Stem Battery, Bretherton, Oppenheim, Buchsbaum, Emde, & the MacArthur Narrative Group, 1990). Predictors included children’s attachment security with mothers and fathers assessed via the Attachment Q-Set (AQS, Waters, 1987) at 3 years, and parent-child narrative quality regarding positive and negative events at 5 years. Participants included 71 children and their mothers and fathers. Structural equation models (SEM) indicated that children’s attachment security exerted a significant indirect effect on children’s mental representations through parent-child narrative quality. Specifically, children’s attachment security with fathers was related to their mental representations via father-child reminiscing about positive events, and children’s attachment security with mothers was related to their mental representations via mother-child reminiscing about negative events. Results are discussed in terms of the development and implications of attachment relationships within the family context.

Cork structural characteristics and their influence on the oxygen ingress through wine stoppers

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL

APPLICATION OF AN IMPUTATION METHOD FOR GEOSPATIAL INVENTORY OF FOREST STRUCTURAL ATTRIBUTES ACROSS MULTIPLE SPATIAL SCALES IN THE LAKE STATES, U.S.A.

Credible spatial information characterizing the structure and site quality of forests is critical to sustainable forest management and planning, especially given the increasing demands and threats to forest products and services. Forest managers and planners are required to evaluate forest conditions over a broad range of scales, contingent on operational or reporting requirements. Traditionally, forest inventory estimates are generated via a design-based approach that involves generalizing sample plot measurements to characterize an unknown population across a larger area of interest. However, field plot measurements are costly and as a consequence spatial coverage is limited. Remote sensing technologies have shown remarkable success in augmenting limited sample plot data to generate stand- and landscape-level spatial predictions of forest inventory attributes. Further enhancement of forest inventory approaches that couple field measurements with cutting edge remotely sensed and geospatial datasets are essential to sustainable forest management. We evaluated a novel Random Forest based k Nearest Neighbors (RF-kNN) imputation approach to couple remote sensing and geospatial data with field inventory collected by different sampling methods to generate forest inventory information across large spatial extents. The forest inventory data collected by the FIA program of US Forest Service was integrated with optical remote sensing and other geospatial datasets to produce biomass distribution maps for a part of the Lake States and species-specific site index maps for the entire Lake State. Targeting small-area application of the state-of-art remote sensing, LiDAR (light detection and ranging) data was integrated with the field data collected by an inexpensive method, called variable plot sampling, in the Ford Forest of Michigan Tech to derive standing volume map in a cost-effective way. The outputs of the RF-kNN imputation were compared with independent validation datasets and extant map products based on different sampling and modeling strategies. The RF-kNN modeling approach was found to be very effective, especially for large-area estimation, and produced results statistically equivalent to the field observations or the estimates derived from secondary data sources. The models are useful to resource managers for operational and strategic purposes.

The Scored Patient-Generated Subjective Global Assessment (PG-SGA) and its Association with Quality of Life in Ambulatory Patients Receiving Radiotherapy

OBJECTIVE: To evaluate the scored Patient-generated Subjective Global Assessment (PG-SGA) tool as an outcome measure in clinical nutrition practice and determine its association with quality of life (QoL). DESIGN: A prospective 4 week study assessing the nutritional status and QoL of ambulatory patients receiving radiation therapy to the head, neck, rectal or abdominal area. SETTING: Australian radiation oncology facilities. SUBJECTS: Sixty cancer patients aged 24-85 y. INTERVENTION: Scored PG-SGA questionnaire, subjective global assessment (SGA), QoL (EORTC QLQ-C30 version 3). RESULTS: According to SGA, 65.0% (39) of subjects were well-nourished, 28.3% (17) moderately or suspected of being malnourished and 6.7% (4) severely malnourished. PG-SGA score and global QoL were correlated (r=-0.66, P<0.001) at baseline. There was a decrease in nutritional status according to PG-SGA score (P<0.001) and SGA (P<0.001); and a decrease in global QoL (P<0.001) after 4 weeks of radiotherapy. There was a linear trend for change in PG-SGA score (P<0.001) and change in global QoL (P=0.003) between those patients who improved (5%) maintained (56.7%) or deteriorated (33.3%) in nutritional status according to SGA. There was a correlation between change in PG-SGA score and change in QoL after 4 weeks of radiotherapy (r=-0.55, P<0.001). Regression analysis determined that 26% of the variation of change in QoL was explained by change in PG-SGA (P=0.001). CONCLUSION: The scored PG-SGA is a nutrition assessment tool that identifies malnutrition in ambulatory oncology patients receiving radiotherapy and can be used to predict the magnitude of change in QoL.