Using a sulfur-bearing silane to improve rubber formulations for potential use in industrial rubber articles

The availability of the coupling agent bis (3-triethoxysilylpropyl)-tetrasulfide (TESPT) has provided an opportunity for enhancing the reinforcing capabilities of precipitated amorphous white silica in rubber. Styrene-butadiene rubber, synthetic polyisoprene rubber (IR), acrylonitrile-butadiene rubber, and natural rubber (NR) containing the same loading of a precipitated silica filler were prepared. The silica surface was pretreated with TESPT, which is a sulfur-bearing bifunctional organosilane to chemically bond silica to the rubber. The rubber compounds were subsequently cured by reacting the tetrasulfane groups of TESPT with double bonds in the rubber chains and the cure was optimized by adding sulfenamide accelerator and zinc oxide. The IR and NR needed more accelerators for curing. Surprisingly, there was no obvious correlation between the internal double bond content and the accelerator requirement for the optimum cure of the rubbers. Using the TESPT pretreated silanized silica was a very efficient method for cross-linking and reinforcing the rubbers. It reduced the use of the chemical curatives significantly while maintaining excellent mechanical properties of the cured rubbers. Moreover, it improved health and safety at work-place, reduced cost, and minimized damage to the environment because less chemical curatives were used. Therefore, TESPT was classified as "green silane" for use in rubber formulations

Comparative study to access coagulation abnormalities in breast cancer

Background: Coagulation abnormalities such as thrombosis and disseminated intravascular coagulation (DIC) are the major factors that play a major role in breast cancer. In this study, coagulation abnormalities were assessed in breast cancer patients to help the clinician in early detection of DIC and management of patients at different stages of breast cancer.Methods: 75 patients were enrolled in the study, 50 were from case group (breast cancer patients) and 25 were selected as control group subjects used to compare the results. All of these subjects undergone, General Hematological analysis i.e. differential leukocyte count hemoglobin, platelets count and total leukocyte count were performed on each of the samples collected from the subjects and Specific Hematological analysis i.e. Activated Partial Thromboplastin Time (APTT), Fibrinogen Assay, Prothrombin Time (PT), D-Dimer Detection and Fibrin Degradation Products (FDPs).Results: PT was found to be comparable in patients with breast cancer when compared with controls. Difference between control group (II) and subjects with breast cancer (I) was non-significant, fibrinogen level was found to be significantly increased (p < 0.01) in patients with different stages of breast cancer when compared with controls. FDPs were found to be significantly increased (p< 0.01) in patients of breast cancer when compared with control group. These increased levels of FDPs may be due to enhanced fibrinolysis. D-Dimers were also found to be significantly increased (p < 0.01) in patients with breast cancer when compared with controls.Conclusion: Patients with breast cancer were associated with compensated DIC state including normal PT and APTT level but increased fibrinogen and platelets count as compared to the controls. Detection of D-Dimers offers a differential analysis over other laboratory tests for DIC

Tibiopedal arterial minimally invasive retrograde revascularization (TAMI) in patients with peripheral arterial disease and critical limb ischemia. On behalf of the Peripheral Registry of Endovascular Clinical Outcomes (PRIME)

Objectives and backgroundComplex peripheral arterial disease (PAD) and critical limb ischemia (CLI) are associated with high morbidity and mortality. Endovascular techniques have become prevalent in treatment of advanced PAD and CLI, and use of techniques such as tibiopedal minimally invasive revascularization (TAMI), have been proven safe in small, singleâ center series. However, its use has not been systematically compared to traditional approaches.Methods and resultsThis is a retrospective, multicenter analysis which enrolled 744 patients with advanced PAD and CLI who underwent 1,195 endovascular interventions between January 2013 and April 2018. Data was analyzed based on access used for revascularization: 840 performed via femoral access, 254 via dual access, and 101 via TAMI. The dual access group had the highest median Rutherford Class and lowest number of patent tibial vessels. Median fluoroscopy time, procedure time, hospital stay, and contrast volume were significantly lower in the TAMI access group when compared to both femoral/dual access groups. There was also a significant difference between all groups regarding location of target lesions: Femoropopliteal lesions were most commonly treated via femoral access; infrapopliteal lesions, via TAMI, and multilevel lesions via dual access.ConclusionsStandâ alone TAMI or tibial access as an integral part of a dual access treatment strategy, is safe and efficacious in the treatment of patients with advanced PAD and CLI who have infrapopliteal lesions. Larger prospective and randomized studies may be useful to further validate this approach.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154326/1/ccd28639.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154326/2/ccd28639_am.pd

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Hierarchical transformations of sensory inputs along the primate dorsal visual pathway

The dorsal pathway of macaque visual cortex is involved in the processing of motion signals that are useful for perception and behaviour. This involves multiple stages, with each stage integrating information from its predecessors. Along these stages, motion information is first measured by the primary visual cortex (V1), which sends specialized projections to extrastriate regions such as the middle temporal area (MT). Previous work with plaid stimuli has shown that most V1 neurons respond to the individual components of moving stimuli, while some MT neurons are capable of estimating the global motion of the pattern. The observation of this pattern-selectivity has led to two-stage models, in which MT neurons integrate the outputs of component-selective V1 neurons. In this thesis we first show (Chapter 2) thatthe majority of neurons in the medial temporal area (MST), which receives input from MT, have this pattern-selective property. We also show that increased pattern selectivity in MST is associated with greater prevalence of the mechanisms (i.e. motion opponency and component integration) implemented by two-stage MT models. Thus the relationship between MST and MT is qualitatively similar to that between MT and V1, as repeated application of basic motion mechanisms leads to novel selectivities at each stage along the pathway. The second and third chapters of this thesis use dissociation of spikes and local field potentials (LFPs) through stimulus selectivity and inactivation of spiking output, respectively, to investigate the anatomical source of the LFP. These experiments suggest that the β and γLband of the LFP exhibit properties similar to the presumptive feedforward input to each area while the γH band reflects local spiking output. Together theresults of this thesis suggest a strong link between the sensory tuning of cortical LFPs and afferent inputs, with important implications for the interpretation of the BOLD signal, which has been shown to correlate with the spike-independent component of the LFP. The thesis also has important implications for the design of Brain-Machine Interfaces, which use the LFP response to decode brain function.Chez le macaque, la voie dorsale du cortex visuel est impliquée dans le traitement des signaux relatifs au mouvement qui sont utiles à la fois pour la perception et le comportement. Ce processus nécessite plusieurs étapes d'intégrations de l'information avec chacune des étapes intégrant l'information acheminée lors des étapes précédentes. Le long de ces étapes, l'information relative au mouvement est d'abord traitée par le cortex visuel primaire (V1) qui envoie des projections spécialisées aux régions extra-striées comme la région moyenne temporale (ou MT). En utilisant un stimulus visuel complexe de type 'plaid', des travaux antérieurs ont montré que la plupart des neurones V1 répondent aux composantes individuelles du stimulus en mouvement, alors que certains neurones du MT sont plutôt capables de traiter l'information concernant le mouvement et/ou le pattern du stimulus dans sa globalité. L'observation de ce type de modèle sélectif (ou modèle-sélectivité) à conduit au modèle à deux étapes au cours duquel les neurones du MT intègrent les informations sortantes sélectives des neurones V1. Dans cette thèse nous montrons tout d'abord (chapitre 2) que la majorité des neurones dans la région médiane temporale (ou MST), qui reçoivent des projections du MT, ont cette propriété de modèle-sélectivité. Nous avons montré également que l'augmentation du modèle-sélectivité dans le MST est associée à la prévalence des mécanismes implémentés par le modèle MT à deux étapes (c'est-à-dire mouvement dans des sens opposés et composante du processus d'intégration). Ainsi, la relation entre le MST et le MT est qualitativement semblable à celle entre le MT et le V1, étant donné qu'une application répétée des mécanismes de base du mouvement conduit à des sélectivités nouvelles à chaque étape le 10 long de cette voie. Dans le deuxième et le troisième chapitre de cette thèse nous avons utilisé les techniques de dissociation des potentiels d'actions ainsi que les potentiels de champs locaux (LFPs) en ayant recours, respectivement, à la stimulation sélective et l'inactivation de décharge neuronale à la sortie afin de déterminer l'origine anatomique du LFP. Nos résultats suggèrent que la bande β et γL de la LFP présente des propriétés semblables à celles des projections entrantes capables de rétroaction anticipative tandis que la bande γH reflète le pattern de décharge des projections sortantes. Ensemble, les résultats de cette thèse suggèrent un lien important entre l'affinement des entrées sensorielles des LFPs corticaux et les autres afférences, avec des implications importantes pour l'interprétation du signal "FORT", qui semble correler avec la composante indépendante du pic du LFP. La thèse a également des implications importantes dans la conception des Interfaces Cerveau- Machine, qui utilisent la réponse du LFP pour décoder le fonctionnement du cerveau

MavHome: An Agent-Based Smart Home

The goal of the MavHome (Managing An Intelligent Versatile Home) project is to create a home that acts as an intelligent agent

Curing rubber compounds efficiently and cost-effectively

Curing rubber compounds efficiently and cost-effectivel