2,013 research outputs found
Updates in the perioperative and emergency management of non-vitamin K antagonist oral anticoagulants.
Perioperative management of patients treated with the non-vitamin K antagonist oral anticoagulants is an ongoing challenge. Due to the lack of good clinical studies involving adequate monitoring and reversal therapies, management requires knowledge and understanding of pharmacokinetics, renal function, drug interactions, and evaluation of the surgical bleeding risk. Consideration of the benefit of reversal of anticoagulation is important and, for some low risk bleeding procedures, it may be in the patient's interest to continue anticoagulation. In case of major intra-operative bleeding in patients likely to have therapeutic or supra-therapeutic levels of anticoagulation, specific reversal agents/antidotes would be of value but are currently lacking. As a consequence, a multimodal approach should be taken which includes the administration of 25 to 50 U/kg 4-factor prothrombin complex concentrates or 30 to 50 U/kg activated prothrombin complex concentrate (FEIBA®) in some life-threatening situations. Finally, further studies are needed to clarify the ideal therapeutic intervention
Fluorescence and absorption properties of chromophoric dissolved organic matter (CDOM) in coastal surface waters of the northwestern Mediterranean Sea, influence of the Rhône River
International audienceSeawater samples were collected monthly in surface waters (2 and 5 m depths) of the Bay of Marseilles (northwestern Mediterranean Sea; 5 • 17 30 E, 43 • 14 30 N) during one year from November 2007 to December 2008 and studied for total organic carbon (TOC) as well as chro-mophoric dissolved organic matter (CDOM) optical properties (absorbance and fluorescence). The annual mean value of surface CDOM absorption coefficient at 350 nm [a CDOM (350)] was very low (0.10 ± 0.02 m −1) in comparison to values usually found in coastal waters, and no significant seasonal trend in a CDOM (350) could be determined. By contrast, the spectral slope of CDOM absorption (S CDOM) was significantly higher (0.023 ± 0.003 nm −1) in summer than in fall and winter periods (0.017 ± 0.002 nm −1), reflecting either CDOM photobleaching or production in surface waters during stratified sunny periods. The CDOM fluorescence, assessed through excitation emission matrices (EEMs), was dominated by protein-like component (peak T; 1.30-21.94 QSU) and marine humic-like component (peak M; 0.55-5.82 QSU), while terrestrial humic-like fluores-cence (peak C; 0.34-2.99 QSU) remained very low. This reflected a dominance of relatively fresh material from biological origin within the CDOM fluorescent pool. At the end of summer, surface CDOM fluorescence was very low and strongly blue shifted, reinforcing the hypothesis of CDOM photobleaching. Our results suggested that unusual Rhône Correspondence to: R. Sempéré ([email protected]) River plume eastward intrusion events might reach Mar-seilles Bay within 2-3 days and induce local phytoplank-ton blooms and subsequent fluorescent CDOM production (peaks M and T) without adding terrestrial fluorescence signatures (peaks C and A). Besides Rhône River plumes, mixing events of the entire water column injected relative aged (peaks C and M) CDOM from the bottom into the surface and thus appeared also as an important source of CDOM in surface waters of the Marseilles Bay. Therefore, the assessment of CDOM optical properties, within the hydrological context, pointed out several biotic (in situ biological production , biological production within Rhône River plumes) and abiotic (photobleaching, mixing) factors controlling CDOM transport, production and removal in this highly urbanized coastal area
Epiretinal implant of human amniotic membrane to treat highly myopic macular hole retinal detachments: A novel surgical technique
Purpose: To describe a new surgical technique involving the use of a human amniotic membrane (hAM) epiretinal patch to treat a primary macular hole retinal detachment (MHRD) in a highly myopic patient. Methods: A 60 years old highly myopic man was referred to our clinic with a diagnosis of MHRD in his right eye. The patient was pseudophakic, with a visual acuity of counting fingers at the baseline evaluation. Pars plana vitrectomy was performed, a small retinotomy was created at the inner margin of the staphyloma, and membrane blue dual was used to obtain an adequate peeling of the inner limiting membrane. Then, a 1.5 mm diameter circular hAM patch was obtained and positioned over the macular hole with the chorion layer settled over the retina. After a complete fluid-air exchange, 20% sulfur hexafluoride gas was used as endotamponade, and the patient was asked to remain face down for three days. Results: Four weeks after surgery, optical coherence tomography (OCT) scan showed the hAM patch, visualized as a distinct hyperreflective layer well integrated with the retina. Nine months after surgery, the macular hole was closed, the retina reattached, the hAM patch was adherent to the retina, and the patient presented a best-corrected visual acuity improved to 0.7 logMar. No postoperative adverse events were registered during the follow-up. Conclusions: Epiretinal hAM implant could represent a novel surgical technique, feasible and easier compared to other current techniques used to treat MHRD in highly myopic patients
Cable Tree Wiring -- Benchmarking Solvers on a Real-World Scheduling Problem with a Variety of Precedence Constraints
Cable trees are used in industrial products to transmit energy and
information between different product parts. To this date, they are mostly
assembled by humans and only few automated manufacturing solutions exist using
complex robotic machines. For these machines, the wiring plan has to be
translated into a wiring sequence of cable plugging operations to be followed
by the machine. In this paper, we study and formalize the problem of deriving
the optimal wiring sequence for a given layout of a cable tree. We summarize
our investigations to model this cable tree wiring Problem (CTW) as a traveling
salesman problem with atomic, soft atomic, and disjunctive precedence
constraints as well as tour-dependent edge costs such that it can be solved by
state-of-the-art constraint programming (CP), Optimization Modulo Theories
(OMT), and mixed-integer programming (MIP) solvers. It is further shown, how
the CTW problem can be viewed as a soft version of the coupled tasks scheduling
problem. We discuss various modeling variants for the problem, prove its
NP-hardness, and empirically compare CP, OMT, and MIP solvers on a benchmark
set of 278 instances. The complete benchmark set with all models and instance
data is available on github and is accepted for inclusion in the MiniZinc
challenge 2020
Restart errors reaction time of a two-step inhibition process account for the violation of the race model’s independence in multi-effector selective stop signal task
Goal-oriented actions often require the coordinated movement of two or more effectors. Sometimes multi-effector movements need to be adjusted according to a continuously changing environment, requiring stopping an effector without interrupting the movement of the others. This form of control has been investigated by the selective Stop Signal Task (SST), requiring the inhibition of an effector of a multicomponent action. This form of selective inhibition has been hypothesized to act through a two-step process, where a temporary global inhibition deactivating all the ongoing motor responses is followed by a restarting process that reactivates only the moving effector. When this form of inhibition takes place, the reaction time (RT) of the moving effector pays the cost of the previous global inhibition. However, it is poorly investigated if and how this cost delays the RT of the effector that was required to be stopped but was erroneously moved (Stop Error trials). Here we measure the Stop Error RT in a group of participants instructed to simultaneously rotate the wrist and lift the foot when a Go Signal occurred, and interrupt both movements (non-selective Stop version) or only one of them (selective Stop version) when a Stop Signal was presented. We presented this task in two experimental conditions to evaluate how different contexts can influence a possible proactive inhibition on the RT of the moving effector in the selective Stop versions. In one context, we provided the foreknowledge of the effector to be inhibited by presenting the same selective or non-selective Stop versions in the same block of trials. In a different context, while providing no foreknowledge of the effector(s) to be stopped, the selective and non-selective Stop versions were intermingled, and the information on the effector to be stopped was delivered at the time of the Stop Signal presentation. We detected a cost in both Correct and Error selective Stop RTs that was influenced by the different task conditions. Results are discussed within the framework of the race model related to the SST, and its relationship with a restart model developed for selective versions of this paradigm
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Modeling hepatic fibrosis in African American and Caucasian American patients with chronic hepatitis C virus infection
Assessment of histological stage is an integral part of disease management in patients infected with the hepatitis C virus (HCV). The aim of this study was to develop a model incorporating objective clinical and laboratory parameters to estimate the probability of severe fibrosis ( i.e. , Ishak fibrosis ≥ 3) in previously untreated African American (AA) and Caucasian American (CA) patients with HCV genotype 1. The Ishak fibrosis scores of 205 CA and 194 AA patients enrolled in the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C study (Virahep-C) were modeled using simple and multiple logistic regression. The model was then validated in an independent cohort of 461 previously untreated patients with HCV. The distribution of fibrosis scores was similar in the AA and CA patients as was the proportion of patients with severe fibrosis (35% vs. 39%, P = .47). After accounting for the number of portal areas in the biopsy, patient age, serum aspartate aminotransferase, alkaline phosphatase, and platelet count were independently associated with severe fibrosis in the overall cohort, and the relationship with fibrosis was similar in both the AA and CA subgroups. The area under the receiver operating characteristic curve (AUROC) of the Virahep-C model (0.837) was significantly better than in other published models ( P = .0003). The AUROC of the Virahep-C model was 0.851 in the validation population. In conclusion , a model consisting of widely available clinical and laboratory features predicted severe hepatic fibrosis equally well in AA and CA patients with HCV genotype 1 and was superior to other published models. The excellent performance of the Virahep-C model in an external validation cohort suggests the findings are replicable and potentially generalizable. (H EPATOLOGY 2006;44:925–935.)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55833/1/21335_ftp.pd
Portal Hypertensive Gastropathy in Chronic Hepatitis C Patients with Bridging Fibrosis and Compensated Cirrhosis: Results from the HALT-C Trial
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72863/1/j.1572-0241.2006.00461.x.pd
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