Quantitative imaging of concentrated suspensions under flow

We review recent advances in imaging the flow of concentrated suspensions, focussing on the use of confocal microscopy to obtain time-resolved information on the single-particle level in these systems. After motivating the need for quantitative (confocal) imaging in suspension rheology, we briefly describe the particles, sample environments, microscopy tools and analysis algorithms needed to perform this kind of experiments. The second part of the review focusses on microscopic aspects of the flow of concentrated model hard-sphere-like suspensions, and the relation to non-linear rheological phenomena such as yielding, shear localization, wall slip and shear-induced ordering. Both Brownian and non-Brownian systems will be described. We show how quantitative imaging can improve our understanding of the connection between microscopic dynamics and bulk flow.Comment: Review on imaging hard-sphere suspensions, incl summary of methodology. Submitted for special volume 'High Solid Dispersions' ed. M. Cloitre, Vol. xx of 'Advances and Polymer Science' (Springer, Berlin, 2009); 22 pages, 16 fig

Effect of Saddle height on skin temperature measured in different days of cycling.

Infrared thermography can be useful to explore the effects of exercise on neuromuscular function. During cycling, it could be used to investigate the effects of saddle height on thermoregulation. The aim of this study was to examine whether different cycling postures, elicited by different knee flexion angles, could influence skin temperature. Furthermore, we also determined whether the reproducibility of thermal measurements in response to cycling differed in the body regions affected or not affected by saddle height. Sixteen cyclists participated in three tests of 45 min of cycling at their individual 50 % peak power output. Each test was performed in a different knee flexion position on the bicycle (20°, 30°, 40° knee flexion when the pedal crank was at 180°). Different knee angles were obtained by changing saddle height. Skin temperatures were determined by infrared thermography before, immediately after and 10 min after the cycling test, in 16 different regions of interest (ROI) in the trunk and lower limbs. Changes in saddle height did not result in changes in skin temperature in the ROI. However, lower knee flexion elicited higher temperature in popliteus after cycling than higher flexion (p = 0.008 and ES = 0.8), and higher knee flexion elicited lower temperature variation in the tibialis anterior than intermediate knee flexion (p = 0.004 and ES = 0.8). Absolute temperatures obtained good and very good intraday reproducibility in the different measurements (ICCs between 0.44 and 0.85), but temperature variations showed lower reproducibility (ICCs between 0.11 and 0.74). Different postures assumed by the cyclist due to different saddle height did not influence temperature measurements. Skin temperature can be measured on different days with good repeatability, but temperature variations can be more sensitive to the effects of an intervention

Common variation in PHACTR1 is associated with susceptibility to cervical artery dissection

Cervical artery dissection (CeAD), a mural hematoma in a carotid or vertebral artery, is a major cause of ischemic stroke in young adults although relatively uncommon in the general population (incidence of 2.6/100,000 per year). Minor cervical traumas, infection, migraine and hypertension are putative risk factors, and inverse associations with obesity and hypercholesterolemia are described. No confirmed genetic susceptibility factors have been identified using candidate gene approaches. We performed genome-wide association studies (GWAS) in 1,393 CeAD cases and 14,416 controls. The rs9349379[G] allele (PHACTR1) was associated with lower CeAD risk (odds ratio (OR) = 0.75, 95% confidence interval (CI) = 0.69-0.82; P = 4.46 × 10(-10)), with confirmation in independent follow-up samples (659 CeAD cases and 2,648 controls; P = 3.91 × 10(-3); combined P = 1.00 × 10(-11)). The rs9349379[G] allele was previously shown to be associated with lower risk of migraine and increased risk of myocardial infarction. Deciphering the mechanisms underlying this pleiotropy might provide important information on the biological underpinnings of these disabling conditions

Clinical and Organizational Factors Related to the Reduction of Mechanical Restraint Application in an Acute Ward: An 8-Year Retrospective Analysis

Background: The purpose of this study was to describe the frequency of mechanical restraint use in an acute psychiatric ward and to analyze which variables may have significantly influenced the use of this procedure. Methods: This retrospective study was conducted in the Servizio Psichiatrico di Diagnosi e Cura (SPDC) of Modena Centro. The following variables of our sample, represented by all restrained patients admitted from 1-1-2005 to 31-12-2012, were analyzed: age, gender, nationality, psychiatric diagnoses, organic comorbidity, state and duration of admission, motivation and duration of restraints, nursing shift and hospitalization day of restraint, number of patients admitted at the time of restraint and institutional changes during the observation period. The above variables were statistically compared with those of all other non-restrained patients admitted to our ward in the same period. Results: Mechanical restraints were primarily used as a safety procedure to manage aggressive behavior of male patients, during the first days of hospitalization and night shifts. Neurocognitive disorders, organic comorbidity, compulsory state and long duration of admission were statistically significantly related to the increase of restraint use (p<.001, multivariate logistic regression). Institutional changes, especially more restricted guidelines concerning restraint application, were statistically significantly related to restraint use reduction (p<.001, chi2 test, multivariate logistic regression). Conclusion: The data obtained highlight that mechanical restraint use was influenced not only by clinical factors, but mainly by staff and policy factors, which have permitted a gradual but significant reduction in the use of this procedure through a multidimensional approach

The cystic fibrosis microbiome in an ecological perspective and its impact in antibiotic therapy

The recent focus on the cystic fibrosis (CF) complex microbiome has led to the recognition that the microbes can interact between them and with the host immune system, affecting the disease progression and treatment routes. Although the main focus remains on the interactions between traditional pathogens, growing evidence supports the contribution and the role of emergent species. Understanding the mechanisms and the biological effects involved in polymicrobial interactions may be the key to improve effective therapies and also to define new strategies for disease control. This review focuses on the interactions between microbe-microbe and host-microbe, from an ecological point of view, discussing their impact on CF disease progression. There are increasing indications that these interactions impact the success of antimicrobial therapy. Consequently, a new approach where therapy is personalized to patients by taking into account their individual CF microbiome is suggested.Portuguese Foundation for Science and Technology (FCT), the strategic funding of UID/BIO/04469/2013-CEB and UID/EQU/00511/2013-LEPABE units. This study was also supported by FCT and the European Community fund FEDER, through Program COMPETE, under the scope of the Projects “DNA mimics” PIC/IC/82815/2007, RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), “BioHealth—Biotechnology and Bioengineering approaches to improve health quality”, Ref. NORTE-07-0124-FEDER-000027 and NORTE-07-0124-FEDER-000025—RL2_ Environment and Health, co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. The authors also acknowledge the grant of Susana P. Lopes (SFRH/BPD/95616/2013) and of the COST-Action TD1004: Theragnostics for imaging and therapy

Northern Eurasia Future Initiative (NEFI): facing the challenges and pathways of global change in the 21st century

During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include: warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land-use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia's role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large scale water withdrawals, land use and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that Integrated Assessment Models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts

Charnley low-friction arthroplasty of the hip. Five to 25 years survivorship in a general hospital

<p>Abstract</p> <p>Background</p> <p>Some studies have raised the question about whether the good results obtained with the Charnley prosthesis could be replicated at general hospitals when it comes to the frequency of early complications and failure rates, both of which would be higher than those published by centres devoted to hip arthroplasties.</p> <p>Methods</p> <p>We reviewed the results of 404 Low Friction Arthroplasties of the hip implanted between 1976 and 1993 in a general hospital by general orthopaedic surgeons. For the survival analysis, the end-point chosen would be the chirurgical revision of any of the prosthetic components for whatever reason.</p> <p>Results</p> <p>The complications were 16 dislocations (4%), 14 deep infections (3.5%), 2 neurological injuries (0,5%) and 5 clinical deep venous thromboses (1.2%) (2 pulmonary embolisms). The survival rate at 25 years, both for stem and cup, was 83%. Survival was higher in those arthroplasties implanted in patients older than 60 years, with statistical significance.</p> <p>Conclusion</p> <p>Low Friction Arthroplasty undertaken at general hospitals by general orthopaedic surgeons feature similar outcomes to those found in centres devoted to hip surgery.</p

Two stage fracture of a polyethylene post in a 9-year-old posterior-stabilized knee prosthesis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Several cases of tibial post breakage are reported in the literature. To the best of our knowledge, only three cases of NexGen knee prosthesis (Zimmer, Warsaw, Indiana, USA) tibial post failure have been reported.</p> <p>Case presentation</p> <p>In November 1999, a 63-year-old Caucasian woman from Italy with a history of symptomatic left knee osteoarthritis underwent a total knee arthroplasty. In March 2008, while rising from a chair, she felt a sudden pain and instability in her left knee. She reported a fracture of the polyethylene post of the tibial insert. No malposition or malalignment of either the femoral or tibial components were identified. The polyethylene tibial insert was studied under light microscopy and scanning electron microscopy. The fracture was also noted to have occurred without any notable polyethylene wear.</p> <p>Conclusion</p> <p>Scanning electron microscopy revealed two different damage patterns that could be explained with a two-stage rupture of our patient's polyethylene post. This could have been caused by a non-optimal ligamentous balancing during first implant surgery. Her knee probably developed a varus instability that weakened the post, and then a posterior anterior stress finally broke the polyethylene.</p