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Dynamics of Micropollutant Adsorption to Polystyrene Surfaces Probed by Angle-Resolved Second Harmonic Scattering
Angle-resolved second harmonic scattering is used to probe the adsorption dynamics of aqueous cationic and anionic dye molecules onto polystyrene surfaces. The adsorptions of malachite green to negatively charged polystyrene and naphthol yellow S to positively charged polystyrene are both highly favorable, with Î"GAds values of -10.9 ± 0.2 and -10.27 ± 0.09 kcal/mol, respectively. A competitive displacement methodology was employed to obtain values for the adsorption free energies of various smaller neutral organic molecules, including the important micropollutant ascorbic acid, caffeine, and pentoxifylline. For charged adsorbers, electrostatic interactions appear to significantly contribute to adsorption behavior. However, electrostatic repulsion does not necessarily deter the adsorption of molecules with large uncharged moieties (e.g., surfactants). In these cases, the mechanism of adsorption is dominated by van der Waals interactions, with the surface charge playing a relatively minor role
Maintaining credibility when communicating uncertainty: The role of communication format
Research into risk communication has commonly highlighted
the disparity between the meaning intended by the
communicator and what is understood by the recipient. Such
miscommunications will have implications for perceived trust
and expertise of the communicator, but it is not known whether
this differs according to the communication format. We
examined the effect of using verbal, numerical and mixed
communication formats on perceptions of credibility and
correctness, as well as whether they influenced a decision to
evacuate, both before and after an ‘erroneous’ prediction (i.e.
an ‘unlikely’ event occurs, or a ‘likely’ event does not occur).
We observed no effect of communication format on any of the
measures pre-outcome, but found the numerical format was
perceived as less incorrect, as well as more credible than the
other formats after an ‘erroneous’ prediction, but only when
low probability expressions were used. Our findings suggest
numbers should be used in consequential risk communications
Muscle fiber and motor unit behavior in the longest human skeletal muscle
The sartorius muscle is the longest muscle in the human body. It is strap-like, up to 600 mm in length, and contains five to seven neurovascular compartments, each with a neuromuscular endplate zone. Some of its fibers terminate intrafascicularly, whereas others may run the full length of the muscle. To assess the location and timing of activation within motor units of this long muscle, we recorded electromyographic potentials from multiple intramuscular electrodes along sartorius muscle during steady voluntary contraction and analyzed their activity with spike-triggered averaging from a needle electrode inserted near the proximal end of the muscle. Approximately 30% of sartorius motor units included muscle fibers that ran the full length of the muscle, conducting action potentials at 3.9 +/- 0.1 m/s. Most motor units were innervated within a single muscle endplate zone that was not necessarily near the midpoint of the fiber. As a consequence, action potentials reached the distal end of a unit as late as 100 ms after initiation at an endplate zone. Thus, contractile activity is not synchronized along the length of single sartorius fibers. We postulate that lateral transmission of force from fiber to endomysium and a wide distribution of motor unit endplates along the muscle are critical for the efficient transmission of force from sarcomere to tendon and for the prevention of muscle injury caused by overextension of inactive regions of muscle fibers
Evolution of surname distribution under gender-equality measurements
We consider a model for the evolution of the surnames distribution under a
gender-equality measurement presently discussed in the Spanish parliament (the
children take the surname of the father or the mother according to alphabetical
order). We quantify how this would bias the alphabetical distribution of
surnames, and analyze its effect on the present distribution of the surnames in
Spain
The case for inclusive area profiling applied in geographic information systems
This paper introduces the history and role of consultation processes of contemporary planning and, after presenting the popularity and criticisms of different practices including communities in urban decision making, it explores how rational planning tools like the geographic information system (GIS) could be exploited to reshape consultation and formally include subjective data in traditional area profiling. Focusing on the popular consultation tool of community mapping, primary and secondary research methods (a literature review, seven interviews to planners and two observational studies) identified seven different problems with contemporary community mapping: spatial and temporal scale, generalisation, integration, representativeness, accessibility, relatedness and visualisation. The conceptualisation, physical modelling and testing of a new community mapping procedure ‘Submap’ is then used to address these problems and discuss (a) the strengths and limitations of formalising community mapping activities for area profiling in GIS and (b) the role of pragmatic research in promoting inclusive practices in contemporary planning
Phase 2 study of combination SPI-1620 with docetaxel as second-line advanced biliary tract cancer treatment
Arthroscopic Treatment of Acetabular Retroversion With Acetabuloplasty and Subspine Decompression: A Matched Comparison With Patients Undergoing Arthroscopic Treatment for Focal Pincer-Type Femoroacetabular Impingement.
BackgroundGlobal acetabular retroversion is classically treated with open reverse periacetabular osteotomy. Given the low morbidity and recent success associated with the arthroscopic treatment of femoroacetabular impingement (FAI), there may also be a role for arthroscopic treatment of acetabular retroversion. However, the safety and outcomes after hip arthroscopic surgery for retroversion need further study, and the effect of impingement from the anterior inferior iliac spine (subspine) in patients with retroversion is currently unknown.HypothesisArthroscopic treatment for global acetabular retroversion will be safe, and patients will have similar outcomes compared with a matched group undergoing arthroscopic treatment for focal pincer-type FAI.Study designCohort study; Level of evidence, 2.MethodsPatients undergoing hip arthroscopic surgery for symptomatic global acetabular retroversion were prospectively enrolled and compared with a matched group of patients undergoing arthroscopic surgery for focal pincer-type FAI. Both groups underwent the same arthroscopic treatment protocol. All patients were administered patient-reported outcome (PRO) measures, including the 12-item Short-Form Health Survey (SF-12) Physical Component Summary (PCS) and a Mental Component Summary (MCS), modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (HOOS), and visual analog scale (VAS) for pain preoperatively and at 1 year postoperatively.ResultsThere were no differences in age, sex, or body mass index between 39 hips treated for global acetabular retroversion and 39 hips treated for focal pincer-type FAI. There were no major or minor complications in either group. Patients who underwent arthroscopic treatment for global acetabular retroversion demonstrated similar significant improvements in postoperative PRO scores (scores increased by 17 to 43 points) as patients who underwent arthroscopic treatment for focal pincer-type FAI. Patients treated for retroversion who also underwent subspine decompression had greater improvement than patients who did not undergo subspine decompression for the HOOS-Pain (33.7 ± 15.3 vs 22.5 ± 17.6, respectively; P = .046) and HOOS-Quality of Life (49.7 ± 18.8 vs 34.6 ± 22.0, respectively; P = .030) scores.ConclusionArthroscopic treatment for acetabular retroversion is safe and provides significant clinical improvement similar to arthroscopic treatment for pincer-type FAI. Patients with acetabular retroversion who also underwent arthroscopic subspine decompression demonstrated greater improvements in pain and quality of life outcomes than those who underwent arthroscopic treatment without subspine decompression
Bilateral Assessment of Functional Tasks for Robot-assisted Therapy Applications
This article presents a novel evaluation system along with methods to evaluate bilateral coordination of arm function on activities of daily living tasks before and after robot-assisted therapy. An affordable bilateral assessment system (BiAS) consisting of two mini-passive measuring units modeled as three degree of freedom robots is described. The process for evaluating functional tasks using the BiAS is presented and we demonstrate its ability to measure wrist kinematic trajectories. Three metrics, phase difference, movement overlap, and task completion time, are used to evaluate the BiAS system on a bilateral symmetric (bi-drink) and a bilateral asymmetric (bi-pour) functional task. Wrist position and velocity trajectories are evaluated using these metrics to provide insight into temporal and spatial bilateral deficits after stroke. The BiAS system quantified movements of the wrists during functional tasks and detected differences in impaired and unimpaired arm movements. Case studies showed that stroke patients compared to healthy subjects move slower and are less likely to use their arm simultaneously even when the functional task requires simultaneous movement. After robot-assisted therapy, interlimb coordination spatial deficits moved toward normal coordination on functional tasks
Lewis X antigen mediates adhesion of human breast carcinoma cells to activated endothelium. Possible involvement of the endothelial scavenger receptor C-Type lectin
Lewis x (Lex, CD15), also known as SSEA-1 (stage specific embryonic antigen-1), is a trisaccharide with the structure Galβ(1–4)Fucα(1–3)GlcNAc, which is expressed on glycoconjugates in human polymorphonuclear granulocytes and various tumors such as colon and breast carcinoma. We have investigated the role of Lex in the adhesion of MCF-7 human breast cancer cells and PMN to human umbilical endothelial cells (HUVEC) and the effects of two different anti-Lex mAbs (FC-2.15 and MCS-1) on this adhesion. We also analyzed the cytolysis of Lex+-cells induced by anti-Lex mAbs and complement when cells were adhered to the endothelium, and the effect of these antibodies on HUVEC. The results indicate that MCF-7 cells can bind to HUVEC, and that MCS-1 but not FC-2.15 mAb inhibit this interaction. Both mAbs can efficiently lyse MCF-7 cells bound to HUVEC in the presence of complement without damaging endothelial cells. We also found a Lex-dependent PMN interaction with HUVEC. Although both anti-Lex mAbs lysed PMN in suspension and adhered to HUVEC, PMN aggregation was only induced by mAb FC-2.15. Blotting studies revealed that the endothelial scavenger receptor C-type lectin (SRCL), which binds Lex-trisaccharide, interacts with specific glycoproteins of Mr␣∼␣28 kD and 10 kD from MCF-7 cells. The interaction between Lex+-cancer cells and vascular endothelium is a potential target for cancer treatment.Fil: Elola, Maria Teresa. Fundación Instituto Leloir; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Capurro, Mariana Isabel. University of Toronto; CanadáFil: Barrio, Maria Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para la Investigación, Docencia y Prevención del Cáncer; ArgentinaFil: Coombs, Peter J.. Imperial College London; Reino UnidoFil: Taylor, Maureen E.. Imperial College London; Reino UnidoFil: Drickamer, Kurt. Imperial College London; Reino UnidoFil: Mordoh, Jose. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para la Investigación, Docencia y Prevención del Cáncer; Argentin
SerpinB2 regulates stromal remodelling and local invasion in pancreatic cancer
Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2(-/-) mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer
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