Laparoscopic Nephroureterectomy: Oncologic Outcomes and Management of Distal Ureter; Review of the Literature

Introduction. Laparoscopic radical nephroureterectomy (LNU) is being increasingly performed at several centers across the world. We review oncologic outcomes after LNU procedure and the techniques for the management of distal ureter. Materials and Methods. A comprehensive review of the literature was performed on the oncological outcomes and management of distal ureter associated with LNU for upper tract transitional cell carcinoma (TCC). Results and Discussion. LNU for upper tract TCC is performed pure laparoscopically (LNU) or hand-assisted (HALNU). The management of the distal ureter is still debated. LNU appears to have superior perioperative outcomes when compared to open surgery. Intermediate term oncologic outcomes after LNU are comparable to open nephroureterectomy (ONU). Conclusions. Excision of the distal ureter and bladder cuff during nephroureterectomy remains controversial. Intermediate term oncologic outcomes for LNU compare well with ONU. Initial long-term oncologic outcomes are encouraging. Prospective randomized comparison between LNU and open surgery is needed to define the role of these modalities in the current context

Will They Stay or Will They Go? An Examination of the Factors Influencing User Loyalty towards News Websites

Owing to the increased competition in electronic markets, customer loyalty has become an important success factor in e-business. However, the antecedents of customer loyalty differ between business domains. While the formation of customer loyalty in e-commerce has been studied extensively, little is known about how loyalty towards news websites develops. Integrating findings from uses and gratifications research into DeLone and McLean’s theory on information systems success, we built a quality-value-satisfaction-loyalty chain for news websites. To test our research model, we conducted a survey and applied partial least squares structural equation modeling. The results reveal that loyalty towards news websites depends on both utilitarian and hedonic value perceptions, which, in turn, are influenced by content quality. Our study combines communication, information systems, as well as marketing research theories and has important implications for news website providers

Numerical Modelling of Composite Materials Based on a Combined Manufacturing-Crash Simulation.

PhDFibre reinforced plastics are widely used for energy dissipating parts. Due to their superior strength to density ratio they provide a high performance and are ideal for lightweight design for crashworthiness. For this, it is essential that the mechanical behaviour of fibre reinforced composites can be predicted correctly by simulation. However, due to the complex inner structure, this is still a challenging task, in particular in case of highly nonlinear crash loading. In this work, a new purely virtual method is developed, which derives the complex fibre structure of a filament wound tube by a chain of numerical simulations. Thereby a finite element simulation of the fibre placement, taking into account the occurring physical effects, constitutes the fundamental base. Based on the results of the manufacturing simulation, a 3D fibre architecture is generated and compared to the real existing structure. The fibre structure, combined with an automatic matrix implementation algorithm, subsequently provides a finite element model of the composite on meso-scale. Using micro-scale analysis, effective material properties for the roving structure, based on filament-matrix interaction, are derived. Incorporation of the effective properties in a USER MATERIAL model completes the finite element model generation. The mesoscale model is subsequently used to analyse the filament wound tube in terms of quasi-static and crash loading. Finally, the obtained results are compared to experimental observations

On the time-optimal 2D-trajectories in non-uniform mediums

This paper addresses two-dimensional trajectory optimization problems, where the mover''s speed monotonically decreases/increases in one of the space''s coordinates. For instance, it is well-known that the absolute value of the helicopter speed decreases in altitude because air pressure drops. Then, it is not trivial to find a time-minimal helicopter trajectory from one given point to another. We address such problems in different settings for the medium (atmosphere) and in the presence of obstacles. First, we consider the basic problem without any obstacles, where the mover''s speed decreases linearly in altitude. We show that the problem is reducible to the L''Hopital problem, one of the well-studied problems in geometrical optics. In this case, the time-optimal trajectory is a circular segment, and therefore can be expressed in a closed analytic form. Next, we adress the problem with linear speed decrease in presence of rectilinear obstacles. We show that this problem can be solved in polynomial time. Finally, we consider the case without obstacles, where the medium is non-uniform and the mover''s velocity is a piece-wise linear concave monotonically decreasing function. This is a widely accepted model in our motivating application of helicopter flights. In this case, we reduce the problem to the solution of a system of polynomial equations of fixed degree. Here, if the number of breakpoints of the velocity function is a constant, the algebraic elimination theory allows us to solve the problem in constant time with any given level of precision.operations research and management science;

The bioavailability of bromazepam, omeprazole and paracetamol given by nasogastric feeding tube

Aims: To characterize and compare the pharmacokinetic profiles of bromazepam, omeprazole and paracetamol when administered by the oral and nasogastric routes to the same healthy cohort of volunteers. Methods: In a prospective, monocentric, randomized crossover study, eight healthy volunteers received the three drugs by the oral (OR) and nasogastric routes (NT). Sequential plasma samples were analyzed by high-performance liquid chromatography-UV, pharmacokinetic parameters (Cmax, $${\text{AUC}}_{0 - \infty }$$ , t½, ke, tmax) were compared statistically, and Cmax, $${\text{AUC}}_{0 - \infty }$$ and tmax were analyzed for bioequivalence. Results: A statistically significant difference was seen in the $${\text{AUC}}_{0 - \infty }$$ of bromazepam, with nasogastric administration decreasing availability by about 25%: AUCOR = 2501 ng mL−1 h; AUCNT = 1855ng mL−1 h (p  0.05); ratio (geometric mean) = 1.01 (90% CI 0.64-1.61). An extended study with a larger number of subjects may possibly provide clearer answers. The narrow 90% confidence limits of paracetamol indicate bioequivalence: AUCOR = 37μg mL−1 h; AUCNT = 41μg mL−1 h(p > 0.05); ratio (geometric mean) = 1.12 (90% CI 0.98-1.28). Conclusion: The results of this study show that the nasogastric route of administration does not appear to cause marked, clinically unsuitable alterations in the bioavailability of the tested drug

Complete enzymic synthesis of the mucin-type sialyl Lewis x epitope, involved in the interaction between PSGL-1 and P-selectin

Sialyl Lewis x (sLex) is an established selectin ligand occurring on N- and O-linked glycans. Using a completely enzymic approach starting from p-nitrophenyl N-acetyl-α-D-galactosaminide (GalNAc(α1-pNp as core substrate, the sLex-oligosaccharide Neu5Ac(α2-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)[Gal(β1-3)]GalNAc(α1-pNp, representing the O-linked form, was synthesized in an overall yield of 32%. In a first step, Gal(β1-3)GalNAc(α1-pNp was prepared in a yield of 52% using UDP-Gal and an enriched preparation of β3-galactosyltransferase (EC 2.4.1.122) from rat liver. UDP-GlcNAc and a recombinant affinity-purified preparation of core 2 β6-N-acetylglucosaminyltransferase (EC 2.4.1.102) fused to Protein A were used to branch the core 1 structure, affording GlcNAc(β1-6)[Gal(β1-3)]GalNAc(α1-pNp in a yield of >85%. The core 2 structure was galactosylated using UDP-Gal and purified human milk β4-galactosyltransferase 1 (EC 2.4.1.38) (yield of >85%), then sialylated using CMP-Neu5Ac and purified recombinant α3-sialyltransferase 3 (EC 2.4.99.X) (yield of 87%), and finally fucosylated using GDP-Fuc and recombinant human α3-fucosyltransferase 6 (EC 2.4.1.152) produced in Pichia pastoris (yield of 100%). Overall 1.5 µmol of product was prepared. MALDI TOF mass spectra, and 1D and 2D TOCSY and ROESY 1H NMR analysis confirmed the obtained structur

Designing Gapped Soft Functions for Jet Production

Distributions in jet production often depend on a soft function, S, which describes hadronic radiation between the jets. Near kinematic thresholds S encodes nonperturbative information, while far from thresholds S can be computed with an operator product expansion (OPE). We design soft functions for jets that serve this dual purpose, reducing to the perturbative result in the OPE region and to a consistent model in the nonperturbative region. We use the MSbar scheme, and in both regions S displays the appropriate renormalization group scale dependence. We point out that viable soft function models should have a gap associated with the minimum hadronic energy deposit. This gap is connected to the leading O(Lambda_QCD) renormalon ambiguity in jet event shapes. By defining the gap in a suitable scheme we demonstrate that the leading renormalon can be eliminated. This improves the convergence of perturbative results, and also the stability by which non-perturbative parameters encode the underlying soft physics.Comment: 17 pages, 5 figure

A GPU Spatial Processing System for CHIME

We present an overview of the Graphics Processing Unit (GPU) based spatial processing system created for the Canadian Hydrogen Intensity Mapping Experiment (CHIME). The design employs AMD S9300x2 GPUs and readily-available commercial hardware in its processing nodes to provide a cost- and power-efficient processing substrate. These nodes are supported by a liquid-cooling system which allows continuous operation with modest power consumption and in all but the most adverse conditions. Capable of continuously correlating 2048 receiver-polarizations across 400\,MHz of bandwidth, the CHIME X-engine constitutes the most powerful radio correlator currently in existence. It receives $6.6$\,Tb/s of channelized data from CHIME's FPGA-based F-engine, and the primary correlation task requires $8.39\times10^{14}$ complex multiply-and-accumulate operations per second. The same system also provides formed-beam data products to commensal FRB and Pulsar experiments; it constitutes a general spatial-processing system of unprecedented scale and capability, with correspondingly great challenges in computation, data transport, heat dissipation, and interference shielding