bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnosis and Management of Isolated Subsegmental Pulmonary Embolism: Review and Assessment of the Options
Authors: Stein Paul D. , Goodman Lawrence R. , Hull Russell D. , Dalen James E. , Matta Fadi
Published: September 2011

We assessed the potential safety of withholding treatment of pulmonary embolism (PE) limited to subsegmental branches. Literature review showed that untreated patients with mostly subsegmental PE had no fatal recurrences in 1 to 3 months and no nonfatal recurrences of PE in 3 months. Patients with suspected PE who had nondiagnostic ventilation/perfusion lung scans, adequate cardiorespiratory reserve or low or moderate clinical probability, and negative serial noninvasive leg tests were shown not to require treatment. It appears safe, therefore, to withhold treatment of subsegmental PE providing (1) pulmonary–respiratory reserve is good; (2) no evidence of deep venous thrombosis (DVT) on serial testing; (3) major risk factor for PE was transient and no longer present; (4) no history of central venous catheterization or atrial fibrillation; and (5) willingness to return for serial venous ultrasound. After fully informing patients, some may choose to be treated and some may choose not to be treated.
The Influence of the ABO Blood Type on the Distribution of von Willebrand Factor in Healthy Children With no Bleeding Symptoms
Authors: Akin Mehmet , Balkan Can , Karapinar Deniz Yilmaz , Kavakli Kaan
Published: September 2011

The purpose of this study was to determine the effect of ABO blood groups on von Willebrand factor–ristocetin cofactor activity (vWF-RCo) and on vWF–antigen (vWF-Ag) in children who have no personal or familial history of bleeding. Material and methods: A survey and testing were performed on 200 children with no personal or familial history of bleeding. In all, 100 of them belonged to blood group O, and the remaining 100 belonged to other blood groups. The blood samples were stored at −80°C for a maximum period of 2 weeks to detect vWF-RCo and vWF-Ag levels. Results: The mean vWF-Ag (±2 standard deviation [SD]) level in children with blood group O was 86% (±20%); and for those with non-O blood group, it was 98.8% (±25%). There was a significant difference between the 2 groups ( P < .001). The mean vWF-RCo (±2 SD) level in children with blood group O was 89% (±23%); and for those with non-O blood group, it was 103% (±17%). There was a significant difference between those in the 2 groups ( P < .001). The lowest value of vWF-Ag and vWF-RCo levels in children with blood group O was found to be 50%. In conclusion, we showed that the selection of normal ranges based on the ABO group might influence the clinical diagnosis of vWD and that while the approach of using ABO group ranges for a vWF-Ag level lower than 50 IU/dL is scientifically sound, it might not be useful to assist a clinician in identifying people at increased risk of bleeding.
Study on dynamic isotropy of a class of symmetric spatial parallel mechanisms with actuation redundancy
Authors: He Jing-Feng , Jiang Hong-Zhou , Tong Zhi-Zhong , Li Bao-Ping , Han Jun-Wei
Published: September 2011

In this paper, we study dynamic isotropy using natural frequency analysis for a class of symmetric spatial parallel mechanisms (SSPMs) with 2 p ( p≥3) struts. This kind of dynamic isotropy has been defined as the square roots of the eigenvalues of the equivalent mass-spring systems formed via the interactions between rigid-body mechanical systems and their driving systems. Analytic expressions for these eigenvalues are then derived in the task space, which is linearly dependent on p. Furthermore, a general compliance center was found for all the SSPMs in which the parallel mechanisms are fully decoupled. Based on the dynamically decoupling, then, dynamic isotropy for the SSPM is discussed which shows that though taking the inertial parameters into consideration, the SSPM can not attain complete dynamic isotropy and the optimal dynamic isotropy index is the quartic root of two. At the end of the paper, to demonstrate these results, an example is given.
Design of a solenoid valve based active engine mount
Authors: Mansour Hossein , Arzanpour Siamak , Golnaraghi Farid
Published: September 2011

This paper describes the design of a versatile and fully controllable active engine mount. The proposed active mount is capable of addressing vibration isolation requirements at various driving conditions. This design addresses a better ride quality that has always been demanded by the automotive industry, as well as satisfying sophisticated vibration isolation requirements for the unconventional engines, i.e. variable displacement, and hybrids. The proposed engine mount replaces the decoupler of the original design with a solenoid actuator. The mathematical model of the active mount is obtained. The dynamic characteristics of the mount are shown to be highly controllable over the operating frequency range of excitation in engines. The effectiveness of the developed active engine mount for various working conditions of engine is also evaluated. Several driving conditions are investigated and proper control strategies are utilized to demonstrate the mount's capability to fulfill the isolation requirements for each condition. The promising results, in addition to compactness, low cost, fail safety, and durability are the main advantages of the proposed active engine mount, which makes it viable for automotive applications.
Diabetes Disease Management in a Home Care Setting
Authors: Dalton Joanne M.
Published: September 2011

The purpose of this Orem’s Self-Care Deficit Theory of Nursing guided project was to extend a program evaluation project to examine the effects of three different approaches to home health care diabetes care on patient self-care behaviors. Group 1 (n = 64) received an experimental Diabetes Disease Management Program, group 2 (n = 167) received a Diabetes Learning Collaborative program, and group 3 (n = 132) received standard diabetes home care. No statistically significant group differences were found for self-care behaviors. Statistically significant associations in group 2 between emergent care and patients who met American Diabetes Association criteria for glucose control regarding discharge management of injectable medication management were found. A significant clinical finding was that 46% of patients (n = 117) did not meet the glucose criteria.
Class-Wide Positive Behavior Support and Group Contingencies
Authors: Wright Robert A. , McCurdy Barry L.
Published: September 2011

The Good Behavior Game (GBG) is a powerful group contingency with a history of documented empirical support. The purpose of this study was to compare two interdependent group contingencies, the GBG and a positive variation, the Caught Being Good Game (CBGG), in a school implementing school-wide positive behavior support. A kindergarten and fourth-grade classroom teacher with 17 and 20 students, respectively, implemented both versions of the game in a counterbalanced fashion. Using a withdrawal design, results showed similar effects on disruptive and on-task behaviors. The CBGG is discussed as an effective variation of the GBG that is acceptable to both teachers and students.
Frictional behaviour of engineering surfaces in overall lubrication regimes of point contacts
Authors: Wang S , Hu Y-Z , Tan Q-C
Published: September 2011

The aim of the present paper is to study experimentally and numerically the frictional behaviour of engineering surfaces within all lubrication regions of point contacts. For this reason, a numerical solution proposed elsewhere by the current authors, which can predict friction under the different lubrication modes of elastohydrodynamic, mixed, and boundary lubrications, is introduced. Based on a deterministic model of mixed lubrication, the solution was combined with the variation of the lubricating films’ physical state during the transition of lubrication modes. Results show that roughness amplitude has a great effect on the transition of friction regimes. In addition, it is also observed that variation of the friction coefficient has nearly the same trend as the true contact area ratio in the mixed lubrication state. Meanwhile, it is concluded that transverse roughness has better film-forming capacity than longitudinal roughness and thus leads to a lower magnitude of friction coefficient if the operating conditions are the same. Analysis of the mechanism of friction behaviour suggests that the true contact area ratio determines the friction behaviour of engineering surfaces in mixed lubrication. In smooth contacts, the comparison of experiment tests and simulation results suggests that friction variation results from gradual change of the liquid lubricant to solid-like matter with diminishing film thickness.
Ultrafine Particle Emissions from Cigarette Smouldering, Incense Burning, Vacuum Cleaner Motor Operation and Cooking
Authors: Wu C. L. , Chao Christopher Y. H. , Sze-To G. N. , Wan M. P. , Chan T. C.
Published: September 2011

Combustion activities such as cigarette smouldering, incense burning and cooking are important sources of particulate matters (PM) in indoor environments. Vacuum cleaning contributes to the non-combustion-related sources of PMs. In this study, we investigated the rates at which ultrafine particles (UFPs) are emitted from cigarettes, incenses and vacuum cleaners in a small test chamber. UFP emission from cooking was obtained by conducting experiments in a residential kitchen. Particle number concentrations and size distributions from these sources were measured using a scanning mobility particle sizer (SMPS) and the UFP emission rates were then determined using a material balance approach. The mean UFP emission rates of cigarette smouldering and incense burning were found to be 3.36 ± 0.34 and 0.44 ± 0.33 × 1011 particles min−1 in terms of the number emission rate, or 22.78 ± 1.21 and 3.48 ± 2.98 × 1015 nm2 min−1 in terms of the surface area emission rate, respectively. Vacuum cleaner motor operation and cooking showed high variations in UFP emission, in the ranges 0.013–0.066 and 4.70–148.29 × 1011 particles min−1, respectively. A database of emission rates for UFP sources can be compiled, which will be useful in estimating the UFP concentration and subsequent human exposure.
Fragility fractures in the elderly: Evolving approaches in the NHS
Authors: Mitra Paramita , Chaudhury Tahseen , Ali SA
Published: September 2011

Fragility fractures account for a significant proportion of trauma admissions and clinic attendances in the UK. Hip fractures constitute a major part of these fractures followed by wrist, spine and humerus. With the increasing elderly population and increasing life expectancy, incidences of these fractures have increased proportionately. Hip fractures cause significant morbidity and mortality because of existing medical co-morbidities or perioperative complications. In order to decrease the overall incidence of osteoporotic fractures and improve outcome of surgical treatment, different approaches to prevention and treatment are currently evolving throughout the NHS. These include primary prevention through management of osteoporosis and secondary prevention aimed at treating osteoporosis and reducing further fractures. In this article, we highlight the different care pathways that could effectively decrease the incidence of fragility fractures as well as the morbidity and mortality in these patients.
Implementation of an efficient muscle fatigue model in the framework of multibody systems dynamics for analysis of human movements
Authors: Pereira A F , Silva M T , Martins J M , de Carvalho M
Published: September 2011

The aim of this study is to implement and integrate a novel and versatile muscle fatigue model in an existing multibody formulation with natural coordinates. The equations of motion of the formulation are rearranged to deal with muscle actuators as externally concentrated forces instead of being considered as kinematic muscle actuator drivers. A muscle fatigue model, originally developed to predict the endurance time of the main body joints, is included in the multibody formulation. The model stems from the compartment theory and uses a bounded controller to rule the rate of motor units changing between the three compartments (resting, activated, and fatigued) that made up the model. The resulting formulation is applied to two example cases involving the human upper extremity, with redundant muscles, to evaluate its robustness and accuracy. Results showed that the proposed methodologies are a valid approach for the calculation of the redundant muscle forces in the presence of muscular fatigue.
Dynamics of flexible detail milling
Authors: Voronov S A , Kiselev I A
Published: September 2011

The five-axis milling operations are commonly used in aerospace industry. For example, this operation is the base for the machining process of the turbine blade production. The milling operations of thin-walled structures cause the vibrations of the tool and the workpiece and this turn affect the quality of the workpiece surface. Modelling of the milling process is necessary to determine the proper cutting conditions for the required productivity and the surface quality. In this article, the geometry modelling algorithm for five-axis milling process is proposed. Dynamics of the machined surface is modelled using the finite-element method. The obtained results make possible to conclude about the stability of milling process and to calculate the efficient processing conditions at which the amplitude of the generated vibrations does not exceed the admissible level. The results of this research can be used while the milling process technologies are designed. Especially, it is significant for the machining of hard-to-machine materials and processing of heat-resistant alloys in space and aircraft industries.
The influence of surface roughness on gibbsite scale development on steel
Authors: Enright E , Curtin T , Haines J , Stanton K T
Published: September 2011

Gibbsite scaling on surfaces such as tanks, pipe-work or measuring equipment is the source of many difficulties in the Bayer process. The study presented here investigates the role of surface roughness of steel in aiding gibbsite scale build-up. Steel surfaces of different temperature roughnesses ( ra = 0.01–1.44 µm) were prepared and tested for gibbsite scaling rates in real Bayer process conditions in pregnant liquor in a filtrate tank. The roughness of the steel samples influenced the scale nucleation time and the strength of adhesion of the scale. The smoother the steel sample, the longer it took to form a complete layer of scale and the lower the adhesion strength. Once a complete layer of scale had formed then the rate of scale-on-scale growth was similar for all samples, as expected. The scale growth rate under the conditions tested was found to be an average of 22.63 mm/year.
Effect of design and operating parameters on the ion current in a single-cylinder diesel engine
Authors: Badawy T , Rai N , Singh J , Bryzik W , Henein N
Published: September 2011

Ion current has been the subject of extensive research in gasoline engines forin-cylinder combustion sensing and as a feedback signal for closed-loop engine control. The sources of the ion current in gasoline engines have been identified. Such identification is not the case in diesel engines. This paper presents experimental data and analysis of the ion current produced in a single-cylinder diesel engine equipped with an electronically controlled common-rail-injection system using an accessible engine control unit. The experiments cover a wide range of engine speeds, loads, injection pressures, and injection timings. The effect of each operating parameter on the shape of the ion current signal, as well as its amplitude, timing, and phase shift relative to the rate of heat release, are determined.
Control-variable-based accommodation of biodiesel blends
Authors: Snyder D B , Adi G H , Hall C H , Shaver G M
Published: September 2011

This paper introduces, and presents experimental validation for, an on-engine applicable control framework for fuel-flexible combustion of diesel–biodiesel blends. The approach is based on changing two of the closed-loop targeted control variables used by the engine control module (ECM): (1) replacing exhaust gas recirculation (EGR) fraction with combustible oxygen mass fraction (COMF); (2) replacing total injected fuel mass with total injected fuel energy, including replacing start of main injection timing with end of main injection timing. It is shown that the stock ECM control structure with pure biodiesel (B100) produces 38 per cent more brake-specific nitrogen oxides (NO x) compared to pure conventional diesel (B0). However, new results presented here with the proposed control framework show that B100 can be made to produce lower brake-specific NO x, 2 per cent higher brake thermal efficiency, 50 per cent lower brake-specific particulate matter, and 1.2 dB lower combustion noise than B0. Benefits of, and novel contributions related to, this strategy are that it is generalizable to other engine systems, is physically based, does not require modified or additional engine calibration, and maintains the stock B0 performance. In essence, the approach presented defines the biodiesel blend control problem as closed-loop targeting of COMF and injected fuel energy, paving the way for future work in controller design to achieve these targets in real-time, on-engine situations.
ProFamilies-dementia: A programme for elderly people with dementia and their families
Authors: Guerra Sara R. , Mendes Álvaro F. , Figueiredo Daniela M. , Sousa Liliana X.
Published: September 2011

In this paper we describe the development and pilot implementation, in a primary care context, of a programme for helping families adapt to living with a person with dementia (proFamilies-dementia). This programme aims to promote the healthy adaptation of the family to the presence of an elderly member with dementia living in their homes. It comprises three components: a psycho-educational, multi-family discussion group for the families; cognitive stimulation for the elderly person with dementia; and a mediation service to support the families after participation in the first two components. proFamilies-dementia was implemented with one group involving five families. The main benefits mentioned by families include: an opportunity to share experiences with others who are living through similar circumstances; the development of an improved sense of competency; and the improvement of family relationships. proFamilies-dementia reveals potential for promoting the provision of integrated support from health and social services, which usually function as independent and parallel support structures.
Self and next of kin's assessment of personality and sense of coherence in elderly people: Implications for dementia care
Authors: Holst Göran , Rennemark Mikael , Hallberg Ingalill R.
Published: September 2011

Nurses sometimes fail to understand the behaviour of individuals with severe dementia. Information from a next of kin may help to bridge this communicative gap. One factor that influences a person's reaction to a disease is their personality and ability to cope with stress. The aim of this study was to evaluate the inter-rater agreement between healthy elderly people's self-assessment and the assessment made by a next of kin concerning personality and sense of coherence. The participants ( n = 154) answered questions from the Eysenck Personality Inventory (EPI) and the Antonovsky Sense of Coherence (SOC) scale. The study shows high or moderate agreement in ratings when analysed by means of an intra-class correlation coefficient (range between r = .57 and r = .72) and the results indicate that in general a close relative is able to report on the personality of a next of kin. The inter-rater agreement was high on SOC and extraversion and somewhat lower on neuroticism. For neuroticism, length of time in the relationship increased the odds for a good inter-rater agreement. Thus, seemingly a next of kin is a reliable informant for the elderly in general and is probably also able to add information useful in the nursing care of people with dementia.
Roman sumptuary legislation: Three concepts of liberty
Authors: Arena Valentina
Published: September 2011

This article argues that, next to a certain intellectual tradition of Roman liberty, often labelled ‘neo-Roman’ or ‘Republican’, we should also take into account the existence of, at least, two other conceptions of liberty, which have so far remained occluded under the prominence of Cicero’s ideas and the appropriation of them by later thinkers. By analysing the debate in opposition and in favour of sumptuary laws enacted from the 3rd century bc onwards, the article identifies a first notion of liberty which coincided with the absence of any external legal constraints upon the citizens’ private life and was, thereby, incompatible with the rule of law in this sphere. The second intellectual family of concepts equated libertas to the absence of constraints from one’s own passions as well as the possession of the capacity to pursue something worth pursuing for the well-being of the community. According to this view, liberty also resided in the supremacy of the rule of law. The third notion of libertas, elaborated by Cicero in the De re publica and De legibus, identified liberty with the absence of arbitrary domination to achieve one’s own ends and resided in the supremacy of the rule of law. Its preservation depended on the constitutional arrangements of the commonwealth and the related civic status of the individual.
A stochastic method for wave run-up on slender circular cylinders due to long-crested and short-crested non-linear random waves
Authors: Myrhaug D , Hesten P , Holmedal L E
Published: September 2011

A practical stochastic method for estimating the wave run-up height on a slender vertical circular cylinder for long-crested (two-dimensional (2D)) and short-crested (three-dimensional (3D)) non-linear random waves is provided. This is achieved by using the velocity stagnation head theory in conjunction with a stochastic approach. Here the waves are assumed to be a stationary narrow-band random process. The effects of non-linear waves are included by adopting the Forristall wave crest height distribution representing both 2D and 3D non-linear random waves. A parameter study is provided and, for both 2D and 3D non-linear random waves, the wave run-up height is larger than for linear random waves. In shallow water, when the water is sufficiently shallow, the maximum wave run-up height is larger for 3D waves than for 2D waves. Comparisons are also made with measurements of the maximum wave run-up heights for 2D random waves in a finite water depth by De Vos et al., and it appears that the data are well predicted if the predictions are calibrated with the data. Therefore the present approach represents a model which can be validated against and adjusted to field data.
What Is Right With Scully Estimates of a Player’s Marginal Revenue Product
Authors: Krautmann Anthony C.
Published: September 2011

The author responds to an article in this edition by Bradbury (in press), which suggests that the free-market approach to estimating a player’s marginal revenue product (MRP) is limited. The author begins by reviewing a number of empirical issues that potentially limit the Scully approach, then turn to Bradbury’s concerns about the free-market approach. The author close by noting that these two methods are not competing nor is one necessarily superior to the other—each method has its own merits in terms of answering different types of questions related to a player’s value.
Constructing the Student Culprit
Authors: Schneider Christopher J.
Published: September 2011

Culprit is a part of a broader definition of rule breaking. Deviance, theft, and cheating are all subparts of culprit, a term generally understood as doing something untoward or wrong. The explicit point is that culprit is more encompassing than deviance, theft, or even cheater, as it includes all of these, and, then some. This article investigates the media production and framing of student culprit, and drawing from some exploratory fieldwork, then illustrates how in some instances these messages permit the expansion of control over students in the classroom. Suggestions for future research are noted.
Joint Use of a Chitosan/PLGA Scaffold and MSCs to Bridge an Extra Large Gap in Dog Sciatic Nerve
Authors: Xue Chengbin , Hu Nan , Gu Yun , Yang Yumin , Liu Yan , Liu Jie , Ding Fei , Gu Xiaosong
Published: September 2011

Background. Tissue-engineered nerve grafts (TENGs) constitute a promising alternative to nerve autografts that are recognized as the gold standard for surgical repair of peripheral nerve gaps. Objective. To investigate the feasibility of using TENGs for bridging extra large peripheral nerve gaps in large animals. Methods. TENGs were constructed by incorporating autologous bone marrow mesenchymal stem cells (MSCs) into a neural scaffold that consisted of a chitosan conduit inserted with poly(lactic-co-glycolic acid) (PLGA) fibers. A 60-mm-long sciatic nerve gap in dogs was bridged by TENGs, chitosan/PLGA scaffolds, or nerve autografts. At 12 months postsurgery, behavioral analysis, electrophysiology, retrograde fluorogold tracing, and histological examination were performed. Results. The outcomes of TENGs were similar to those of autografts and better than those of scaffolds alone. Conclusion. Introduction of autologous MSCs to a chitosan/PLGA scaffold improved the repair and rehabilitation of a large gap after peripheral nerve injury in dogs. Autologous MSCs may be a source of support cells for neural tissue engineering.
Beyond the intention-to-treat in comparative effectiveness research
Authors: Hernán Miguel A , Hernández-Díaz Sonia
Published: September 2011

Background The intention-to-treat comparison is the primary, if not the only, analytic approach of many randomized clinical trials.

Purpose To review the shortcomings of intention-to-treat analyses, and of ‘as treated’ and ‘per protocol’ analyses as commonly implemented, with an emphasis on problems that are especially relevant for comparative effectiveness research.

Methods and Results In placebo-controlled randomized clinical trials, intention-to-treat analyses underestimate the treatment effect and are therefore nonconservative for both safety trials and noninferiority trials. In randomized clinical trials with an active comparator, intention-to-treat estimates can overestimate a treatment’s effect in the presence of differential adherence. In either case, there is no guarantee that an intention-to-treat analysis estimates the clinical effectiveness of treatment. Inverse probability weighting, g-estimation, and instrumental variable estimation can reduce the bias introduced by nonadherence and loss to follow-up in ‘as treated’ and ‘per protocol’ analyses.

Limitations These analyse require untestable assumptions, a dose-response model, and time-varying data on confounders and adherence.

Conclusions We recommend that all randomized clinical trials with substantial lack of adherence or loss to follow-up are analyzed using different methods. These include an intention-to-treat analysis to estimate the effect of assigned treatment and ‘as treated’ and ‘per protocol’ analyses to estimate the effect of treatment after appropriate adjustment via inverse probability weighting or g-estimation.
Tetherin has negligible activity in restricting hepatitis C virus in hepatocytes
Authors: Ye Li , Wang Xu , Li Jieliang , Liu Jinping , Ramirez Servio H , Wu Jianguo , Ho Wenzhe
Published: September 2011

We investigated the ability of tetherin, a recently identified antiviral factor, in restricting hepatitis C virus (HCV) in the Japanese fulminant hepatitis-1 (JFH-1) infectious cell culture system. Human hepatocytes (Huh7, Huh7.5.1) expressedlow levels of endogenous tetherin, which could be induced by IFN-α. However, tetherin contributes little to IFN-α-mediated anti-HCV JFH-1 activity. Although tetherin could inhibit Vpu-deleted HIV-1 release, it had negligible activity in restricting HCV JFH-1 release from hepatocytes, which was evidenced by unaffected levels of intracellular/extracellular HCV RNA and infectious virus. The failure of tetherin’s anti-HCV activity could not be related to the counteraction of HCV, as HCV infection of hepatocytes affected neither tetherin expression nor anti-HIV function of tetherin. These observations imply that tetherin has negligible activity in the restriction of HCV JFH-1 in human hepatocytes.
Public Sphere 2.0? The Democratic Qualities of Citizen Debates in Online Newspapers
Authors: Ruiz Carlos , Domingo David , Micó Josep Lluís , Díaz-Noci Javier , Meso Koldo , Masip Pere
Published: September 2011

Comments in online news could be the contemporary enactment of the eighteenth-century cafés that founded public sphere. This article assesses to what extent do these forms of digital discussion fit in Habermas’ principles for democratic debate, using his discursive ethics as a demanding normative benchmark. The sample of more than 15,000 comments was selected from the online versions of five national newspapers of record from different political and journalistic contexts: The Guardian (United Kingdom), Le Monde (France), The New York Times (United States), El País (Spain), and La Repubblica (Italy). The ethical guidelines and legal frameworks set up by the newspapers as well as their moderation strategies were considered to understand the different settings of the conversations. Two models of audience participation emerge from the analysis, one where communities of debate are formed based on mostly respectful discussions between diverse points of view and another of homogenous communities, in which expressing feelings about current events dominates the contributions and there is less of an argumentative debate.
Prototype tooling for producing small series of polymer microparts
Authors: Griffiths C A , Dimov S S , Hirshy H , Scholz S , Fischer S , Spitzbart M
Published: September 2011

Layer-based manufacture of three-dimensional functional models and concept prototypes play a crucial role in the early assessment and verification of product designs. Any change of design, which is frequently needed during product development, causes the development costs to rise significantly. However, there is a limited set of materials available for layer-based manufacturing, especially for producing polymer microcomponents. Therefore, for fabricating small batches of microcomponents in the required material it is necessary to develop rapid tooling process chains, e.g. for low-pressure injection moulding. This paper investigates the moulding performance of µSL inserts as a function of tool geometry in combination with the effects of process factors. Condition monitoring techniques applied to the µ-IM process have been carried out to provide information that can be used to optimize the process. It was found that small batches of parts with fine details and relatively high aspect ratio structures can be produced and that reduced pressure loads and in particular the decrease of the µSL inserts layer thickness can extend the tool life.
Ex vivo expansion of human Tregs specific for alloantigens presented directly or indirectly
Authors: Veerapathran Anandharaman , Pidala Joseph , Beato Francisca , Yu Xue-Zhong , Anasetti Claudio
Published: September 2011

Adoptive transfer of regulatory T cells (Tregs) prevents GVHD in experimental animals. Because antigen activation drives Treg function, we measured the frequency, growth requirements, and function of alloantigen-specific (allospecific) Tregs from human blood. When alloantigen was presented directly, the precursor frequency of allo-specific Tregs in normal individuals was 1.02% (95% confidence interval [95% CI]: 0.65-1.59) and non-Tregs 1.56% (95% CI: 0.94-2.55). When alloantigen was presented indirectly, the frequency of specific Tregs was approximately 100-fold less. Purified Tregs were expanded with APCs, rapamycin, IL-2, and IL-15. In 12 days, allo-specific Tregs expanded 793-fold (95% CI: 480-1107), with duplication approximately every 24 hours. Purified allo-specific Tregs suppressed responses to specific alloantigen selectively and were approximately 100-fold more potent than polyspecific Tregs and nonexpanded Tregs. Allo-specific Tregs maintained high expression of Foxp3, Bcl-2, lymphoid homing receptor CD62L, and chemokine receptor CCR7, predicting sustained function and migration to lymphoid tissues in vivo. Allo-specific Tregs produced TGF-β and IL-10 and expressed more cytoplasmic CTLA-4 compared with non-Tregs. These data provide a platform for the selective expansion of Tregs against major and possibly minor histocompatibility antigens and predict the feasibility of adoptive immunotherapy trials using Tregs with indirect allo-recognition for preventing GVHD while sparing GVL effects.
Functional characterization of the Saccharomyces cerevisiae protein Chl1 reveals the role of sister chromatid cohesion in the maintenance of spindle length during S-phase arrest
Authors: Laha Suparna , Das Shankar P , Hajra Sujata , Sanyal Kaustuv , Sinha Pratima
Published: September 2011

Background

Metaphase cells have short spindles for efficient bi-orientation of chromosomes. The cohesin proteins hold sister chromatids together, creating Sister Chromatid Cohesion (SCC) that helps in the maintenance of short spindle lengths in metaphase. The budding yeast protein Chl1p, which has human homologs, is required for DNA damage repair, recombination, transcriptional silencing and aging. This protein is also needed to establish SCC between sister chromatids in S-phase.

Results

In the present study we have further characterized Chl1p for its role in the yeast Saccharomyces cerevisiae when cells are under replication stress. We show that when DNA replication is arrested by hydroxyurea (HU), the chl1 mutation causes growth deficiency and a mild loss in cell viability. Although both mutant and wild-type cells remained arrested with undivided nuclei, mutant cells had mitotic spindles, which were about 60-80% longer than wild-type spindles. Spindle extension occurred in S-phase in the presence of an active S-phase checkpoint pathway. Further, the chl1 mutant did not show any kinetochore-related defect that could have caused spindle extension. These cells were affected in the retention of SCC in that they had only about one-fourth of the normal levels of the cohesin subunit Scc1p at centromeres, which was sufficient to bi-orient the chromosomes. The mutant cells showed defects in SCC, both during its establishment in S-phase and in its maintenance in G2. Mutants with partial and pericentromeric cohesion defects also showed spindle elongation when arrested in S-phase by HU.

Conclusions

Our work shows that Chl1p is required for normal growth and cell viability in the presence of the replication block caused by HU. The absence of this protein does not, however, compromize the replication checkpoint pathway. Even though the chl1 mutation gives synthetic lethal interactions with kinetochore mutations, its absence does not affect kinetochore function; kinetochore-microtubule interactions remain unperturbed. Further, chl1 cells were found to lose SCC at centromeres in both S- and G2 phases, showing the requirement of Chl1p for the maintenance of cohesion in G2 phase of these cells. This work documents for the first time that SCC is an important determinant of spindle size in the yeast Saccharomyces cerevisiae when genotoxic agents cause S-phase arrest of cells.
In Vitro Assessment of Tobacco Smoke Toxicity at the BBB: Do Antioxidant Supplements Have a Protective Role?
Authors: Hossain Mohammed , Mazzone Peter , Tierney William , Cucullo Luca
Published: September 2011

Background

Tobacco smoke (TS) contains highly reactive oxygen species (such as hydrogen peroxide, peroxynitrite, etc), which cause oxidative damage in vascular tissue and may exacerbate inflammatory events leading to the blood-brain barrier damage (BBBD) which accompanies the development of a variety of neurological disorders. Smokers often have elevated leukocyte counts (primarily neutrophils and monocytes), and significant decreases in plasma alpha-tocopherol (vitamin E) and ascorbic acid (vitamin C) levels due to increased anti-oxidative mobilization in response to oxidative stress evoked by TS. For this purpose, using static culture systems and a well-established dynamicin vitroBBB model (DIV-BBB) we tested the hypothesis that antioxidant vitamin supplementation (E and/or C) can protect the BBB during exposure to whole soluble TS.

Results

TS exacerbates inflammatory events and leads to endothelial overexpression of vascular adhesion molecules (VCAM-1, P-selectin and E-selectin), release of pro-inflammatory cytokines (TNF-α and IL-6) and nitric oxide (NO), release and activation of matrix metalloproteinases (MMP-2 and MMP-9), monocytic maturation into macrophages, and adhesion to the vascular endothelium. Furthermore, TS altered the normal glucose metabolic behaviour ofin vitroBBB capillaries and caused a period of transient anaerobic respiration to meet the cellular bioenergetic demand. Pre-treatment with antioxidant vitamins (C and/or E) effectively reduced the pro-inflammatory activity associated with TS, protecting the viability and functions of the BBB.

Conclusion

Our results have shown that loss of endothelial viability as well as BBB function and integrity caused by TS exposure can be prevented or at least reduced by normal physiologic concentrations of antioxidant vitaminsin vitro.
HIV Surveillance in a Large, Community-Based Study: Results from the Pilot Study of Project Accept (HIV Prevention Trials Network 043)
Authors: Piwowar-Manning Estelle , Fiamma Agnes , Laeyendecker Oliver , Kulich Michal , Donnell Deborah , Szekeres Greg , Robins-Morris Laura , Mullis, Caroline E , Vallari Ana , Hackett John , Mastro Timothy D , Gray Glenda , Richter Linda , Alexandre Michel W , Chariyalertsak Suwat , Chingono, Alfred , Sweat Michael , Coates Thomas , Eshleman Susan H
Published: September 2011

Background

Project Accept is a community randomized, controlled trial to evaluate the efficacy of community mobilization, mobile testing, same-day results, and post-test support for the prevention of HIV infection in Thailand, Tanzania, Zimbabwe, and South Africa. We evaluated the accuracy of in-country HIV rapid testing and determined HIV prevalence in the Project Accept pilot study.

Methods

Two HIV rapid tests were performed in parallel in local laboratories. If the first two rapid tests were discordant (one reactive, one non-reactive), a third HIV rapid test or enzyme immunoassay was performed. Samples were designated HIV NEG if the first two tests were non-reactive, HIV DISC if the first two tests were discordant, and HIV POS if the first two tests were reactive. Samples were re-analyzed in the United States using a panel of laboratory tests.

Results

HIV infection status was correctly determined based on-in country testing for 2,236 (99.5%) of 2,247 participants [7 (0.37%) of 1,907 HIV NEG samples were HIV-positive; 2 (0.63%) of 317 HIV POS samples were HIV-negative; 2 (8.3%) of 24 HIV DISC samples were incorrectly identified as HIV-positive based on the in-country tie-breaker test]. HIV prevalence was: Thailand: 0.6%, Tanzania: 5.0%, Zimbabwe 14.7%, Soweto South Africa: 19.4%, Vulindlela, South Africa: 24.4%, (overall prevalence: 14.4%).

Conclusions

In-country testing based on two HIV rapid tests correctly identified the HIV infection status for 99.5% of study participants; most participants with discordant HIV rapid tests were not infected. HIV prevalence varied considerably across the study sites (range: 0.6% to 24.4%).

Trial Registration

ClinicalTrials.gov registry number NCT00203749.
A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa
Authors: Bastien S , Kajula LJ , Muhwezi WW
Published: September 2011

Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies.
Emergence of Japanese encephalitis virus genotype V in the Republic of Korea
Authors: Takhampunya Ratree , Kim Heung-Chul , Tippayachai Bousaraporn , Kengluecha Ampornpan , Klein Terry A , Lee Won-Ja , Grieco John , Evans Brian P
Published: September 2011

Background

Japanese encephalitis virus (JEV) genotype V reemerged in Asia (China) in 2009 after a 57-year hiatus from the continent, thereby emphasizing a need to increase regional surveillance efforts. Genotypic characterization was performed on 19 JEV-positive mosquito pools (18 pools of Culex tritaeniorhynchus and 1 pool of Cx. bitaeniorhynchus) from a total of 64 positive pools collected from geographically different locations throughout the Republic of Korea (ROK) during 2008 and 2010.

Findings

Two regions of the JEV genome were sequenced from 19 pools; the envelope gene and the nonstructural protein 5 (NS5)/3'-untranslated region (UTR). Eighteen pools of Culex tritaeniorhynchus and one pool of Cx. bitaeniorhynchus were positive for genotype I and genotype V, respectively. Sequence alignment of the complete E gene from Cx. bitaeniorhynchus showed high amino acid similarity (98.8%) to the Muar strain, characterized as the first report of genotype V, isolated from an encephalitis patient in Malaysia in 1952.

Conclusion

This study represents the first report of JEV genotype V in the ROK. The reemergence of genotype V in Asia (China and ROK) after more than a half-century and its discovery in Cx. bitaeniorhynchus, a mosquito species previously unknown to carry JEV in the ROK, emphasizes the need for enhanced JE surveillance to monitor the dynamics of JEV strains within the region. Future findings may have implications with regard to JEV vaccination/prevention strategies.
Effects of copper nanoparticle exposure on host defense in a murine pulmonary infection model
Authors: Kim Jong Sung , Adamcakova-Dodd Andrea , O'Shaughnessy Patrick T , Grassian Vicki H , Thorne Peter S
Published: September 2011

Background

Human exposure to nanoparticles (NPs) and environmental bacteria can occur simultaneously. NPs induce inflammatory responses and oxidative stress but may also have immune-suppressive effects, impairing macrophage function and altering epithelial barrier functions. The purpose of this study was to assess the potential pulmonary effects of inhalation and instillation exposure to copper (Cu) NPs using a model of lung inflammation and host defense.

Methods

We used Klebsiella pneumoniae (K.p.) in a murine lung infection model to determine if pulmonary bacterial clearance is enhanced or impaired by Cu NP exposure. Two different exposure modes were tested: sub-acute inhalation (4 hr/day, 5 d/week for 2 weeks, 3.5 mg/m3) and intratracheal instillation (24 hr post-exposure, 3, 35, and 100 μg/mouse). Pulmonary responses were evaluated by lung histopathology plus measurement of differential cell counts, total protein, lactate dehydrogenase (LDH) activity, and inflammatory cytokines in bronchoalveolar lavage (BAL) fluid.

Results

Cu NP exposure induced inflammatory responses with increased recruitment of total cells and neutrophils to the lungs as well as increased total protein and LDH activity in BAL fluid. Both inhalation and instillation exposure to Cu NPs significantly decreased the pulmonary clearance of K.p.-exposed mice measured 24 hr after bacterial infection following Cu NP exposure versus sham-exposed mice also challenged with K.p (1.4 × 105 bacteria/mouse).

Conclusions

Cu NP exposure impaired host defense against bacterial lung infections and induced a dose-dependent decrease in bacterial clearance in which even our lowest dose demonstrated significantly lower clearance than observed in sham-exposed mice. Thus, exposure to Cu NPs may increase the risk of pulmonary infection.
Variable-angle total internal reflection fluorescence microscopy of intact cells of Arabidopsis thaliana
Authors: Wan Yinglang , Ash William M , Fan Lusheng , Hao Huaiqin , Kim Myung K , Lin Jinxing
Published: September 2011

Background

Total internal reflection fluorescence microscopy (TIRFM) is a powerful tool for observing fluorescently labeled molecules on the plasma membrane surface of animal cells. However, the utility of TIRFM in plant cell studies has been limited by the fact that plants have cell walls, thick peripheral layers surrounding the plasma membrane. Recently, a new technique known as variable-angle epifluorescence microscopy (VAEM) was developed to circumvent this problem. However, the lack of a detailed analysis of the optical principles underlying VAEM has limited its applications in plant-cell biology.

Results

Here, we present theoretical and experimental evidence supporting the use of variable-angle TIRFM in observations of intact plant cells. We show that when total internal reflection occurs at the cell wall/cytosol interface with an appropriate angle of incidence, an evanescent wave field of constant depth is produced inside the cytosol. Results of experimental TIRFM observations of the dynamic behaviors of phototropin 1 (a membrane receptor protein) and clathrin light chain (a vesicle coat protein) support our theoretical analysis.

Conclusions

These findings demonstrate that variable-angle TIRFM is appropriate for quantitative live imaging of cells in intact tissues of Arabidopsis thaliana.