Search results for "block"

On the Benefits of Random Linear Coding for Unicast Applications in Disruption Tolerant Networks

2006

In this paper, we investigate the benefits of using a form of network coding known as Random Linear Coding (RLC) for unicast communications in a mobile Disruption Tolerant Network (DTN) under epidemic routing. Under RLC, DTN nodes store and then forward random linear combinations of packets as they encounter other DTN nodes. We first consider the case where there is a single block of packets propagating in the network and then consider the case where blocks of K packets arrive according to a Poisson arrival process. Our performance metric of interest is the delay until the last packet in a block is delivered. We show that for the single block case, when bandwidth is constrained, applying RL…

Perioperative diaphragm point-of-care ultrasound as a prediction tool of postoperative respiratory failure in high-risk patients: A feasibility study…

2021

Abstract Introduction Respiratory muscle function in the postoperative period is a key to whether a patient develops Postoperative Respiratory Failure (PRF) or not. PRF occurs when the gas exchange does not meet metabolic needs. Ipsilateral paralysis of the hemidiaphragm after interscalenic brachial plexus block (ISB) causes an acute reduction of respiratory muscle function. This reduction does not cause PRF when the contralateral hemidiaphragm generates enough gas exchange to meet metabolic demands. Objectives To study the evolution of hemidiaphragmatic muscle function during the perioperative period with diaphragmatic ultrasound (D-POCUS), and use it as an innovative tool to predict PRF, …

Blocks of the Trunk and Perineum

1988

Intercostal nerve block was derived from thoracic paravertebral block. Its origin can thus be traced to the beginning of the century (see Sect. VII. B).

157 Patient satisfaction and safety of sedation using perineurial dexmedetomidine in axillary brachial plexus block for wrist surgery

2021

Background and Aims Dexmedetomidine is known to prolong the duration of regional block while its sedative effect when administered perineurally is unknown.[1] We aim to evaluate the effect of perineural Dexmedetomidine on the systemic sedation in patients after axillary brachial plexus block (ABPB). Methods This prospective randomized control trial includes 78 patients undergoing wrist surgery receiving ABPB. The study was conducted with the approval of Ethics Committee of Riga Stradins University. Patients were randomized into two groups – control (CG) (N=39) and study group (SG) (N=39). Both groups received ABPB with a standard dose of local anaesthetics. The study group also received 100…

Injection pressure mapping of intraneural vs. perineural injections: further lessons from cadaveric studies.

2018

Background The aim of the study was to investigate the difference between intraneural and perineural injection pressures in human cadavers. Targeted nerves included the cervical roots, the supraclavicular and infraclavicular brachial plexus, the sciatic-subgluteal nerve and the common peroneal and tibial nerves. Methods Ten readings were obtained for each nerve location. Over ten seconds, 1 mL of 0.9% NaCl was injected - deliberately slower than in clinical practice to eliminate the risk of aberrant readings relating to the speed of injection. Perineural injections occurred at least 1 mm outside the epineurium. After pressure recordings were completed 0.1mL of dye was injected, and dissecti…

ESRA19-0618 Vulnerability of different nerves to intrafascicular injection with different needle bevel types and needle angles: a mathematical model

2019

Background and aims Intrafascicular injection of a local anesthetic, its toxicity, and direct needle trauma to nerve tissue are generally considered the primary reasons for nerve injury after intraneural injection. We hypothesize that the only way that the local anesthetic can enter the fascicle is if at least 80% of the distal needle orifice is inside the fascicle. the aim of this study was to calculate the theoretical vulnerability of nerve fascicles given their actual sizes and that of different needle openings. Methods We superimposed microscopic images of two routinely used nerve block needles (a 22-G, 15 ‘StimuplexOD’ needleand a 22-G, 30 ‘StimuplexOUltra 360O’ needle) over microscopi…

Scalable Electro-Optic Control of Localized Bistable Switching in Broad-Area VCSELs Using Reconfigurable Funnel Waveguides

2017

We demonstrate a steplike optical modulation based on the activation and deactivation of a bistable localized structure using a photoinduced and reconfigurable miniaturized 30 × 30 μm electroactivated funnel waveguide. Control of a single 10-μm-diameter spot in a 200-μm-diameter vertical-cavity surfaceemitting laser at 980 nm is achieved modulating the phase of an exciting beam in the specific position of the spot in the cavity. This localized on-off response can be scaled into arrays and offer a possible route to fast integrated optical logical functions and memory at low intensities at near-infrared wavelengths.

THAP11 and HP1BP3 proteins are component of the HB-2.8 enhancer-blocker located in the human c-MYC chromatin domain.

2011

Adsorption of triblock copolymers and their homopolymers at laponite clay/solution interface. Role played by the copolymer nature

2009

The adsorption thermodynamics of copolymers, based on ethylene oxide (EO) and propylene oxide ( PO) units, at the laponite (RD) clay/liquid interface was determined at 298 K. The copolymer nature was tuned at molecular level by changing the hydrophilicity, the architecture and the molecular weight (Mw) keeping constant the EO/PO ratio. Polyethylene (PEGs) and polypropylene (PPGs) glycols with varying Mw and their mixture were also investigated to discriminate the role of the EO and the PO segments in the adsorption process. Enthalpies of transfer of RD, at fixed concentration, from water to the aqueous macromolecule solutions as functions of the macromolecule molality were determined. They …

Microphase separation in linear multiblock copolymers under poor solvent conditions

2010

Molecular dynamics simulations are used to study the phase behavior of linear multiblock copolymers with two types of monomers, A and B, where the length of the polymer blocks $N_{A}$ and $N_{B}$ ($N_{A}=N_{B}=N$), the number of the blocks $n_{A}$ and $n_{B}$ ($n_{A}=n_{B}=n$), and the solvent quality varies. The fraction $f$ of A-type monomers is kept constant and equal to 0.5. Whereas at high enough temperatures these macromolecules form coil structures, where each block A or B forms rather individual clusters, at low enough temperatures A and B monomers from different blocks can join together forming clusters of A or B monomers. The dependence of the formation of these clusters on the va…