Reinforcement Options Research Articles

Mirtazapine and ketanserin alter preference for gambling-like schedules of reinforcement in rats

Drug and behavioral addictions have overlapping features, e.g., both manifest preference for larger, albeit costlier, reinforcement options in cost/benefit decision-making tasks. Our prior work revealed that the mixed-function serotonergic compound, mirtazapine, attenuates behaviors by rats motivated by abused drugs. To extend this work to behavioral addictions, here we determined if mirtazapine and/or ketanserin, another mixed-function serotonin-acting compound, can alter decision-making in rats that is independent of drug (or food)-motivated reward. Accordingly, we developed a novel variable-ratio task in rats wherein intracranial self-stimulation was used as the positive reinforcer. Using lever pressing for various levels of brain stimulation, the operant task provided choices between a small brain stimulation current delivered on a fixed-ratio schedule (i.e., a predictable reward) and a large brain stimulation delivered following an unpredictable number of responses (i.e., a variable-ratio schedule). This task allowed for demonstration of individualized preference and detection of shifts in motivational influences during a pharmacological treatment. Once baseline preference was established, we determined that pretreatment with mirtazapine or ketanserin significantly decreased preference for the large reinforcer presented after gambling-like schedules of reinforcement. When the rats were tested the next day without drug, preference for the unpredictable large reinforcer option was restored. These data demonstrate that mirtazapine and ketanserin can reduce preference for larger, costlier reinforcement options, and illustrate the potential for these drugs to alter behavior.

Thoracoscopic modified pleural tent for spontaneous pneumothorax.

We developed a modified pleural tent (m-tent) procedure and used it in our hospital in almost 30 consecutive patients with spontaneous pneumothorax. The objective of this study was to clarify the feasibility and effectiveness of a thoracoscopic m-tent for the treatment of spontaneous pneumothorax. From July 2013 to November 2014, 107 patients with spontaneous pneumothorax were treated in our institution. Eighty-nine of these patients were analysed retrospectively. The inclusion criteria for thoracoscopic m-tent for spontaneous pneumothorax were multiple and widespread bullae, postoperative relapse and secondary spontaneous pneumothorax. The surgical procedures were usually performed through three ports. After bullectomy, an m-tent is made to strip the parietal pleura off the chest wall from about the level of the fourth or fifth rib to the apex, and two or three ligations are then applied to fix the pleural tent and lung parenchyma. Patients in whom an m-tent was not indicated underwent bullectomy plus coverage using absorbable materials. Twenty-seven patients underwent bullectomy plus m-tent (m-tent group) and 62 underwent bullectomy plus coverage over a staple line using an absorbable material such as a polyglycolic acid sheet or nitrocellulose sheet (coverage group). No severe postoperative complications were observed in either group. The m-tent and coverage groups showed significant differences in operation time (129 vs 86 min, mean), haemorrhage (12.8 vs 7.2 ml), postoperative hospital stay (3.7 vs 2.9 days) and postoperative painkiller intake (8.6 vs 6.8 days). Recurrence was observed in 1 (3.7%) and 2 patients (3.2%), respectively. The thoracoscopic m-tent procedure requires a longer operation, a longer hospital stay and greater painkiller intake. However, these differences are acceptable, and an m-tent should be considered as an option for pleural reinforcement in spontaneous pneumothorax, especially in patients who are complicated with severe pulmonary emphysema, widespread bullae or recurrent pneumothorax.

Innovations in cement-based materials: Addressing sustainability in structural and infrastructure applications

Abstract

PTU-247 Does enhanced recovery after colorectal surgery increase the incidence of parastomal hernias?

<h3>Introduction</h3> Evidence supporting the benefits of enhanced recovery after surgery (ERAS) protocols is abundant; however there is no published data on how ERAS may affect the incidence of parastomal hernias. <h3>Method</h3> Retrospective, observational, single centre cohort study of patients who underwent elective or emergency operations with stoma formation from January 2006 until March 2013. The cohort was split into ERAS and traditional recovery, and a review of case-notes and stoma nurse records allowed identification of those who developed parastomal hernias at any time point post-operatively. <h3>Results</h3> 208 patients were included; 95 underwent a traditional recovery, and 113 underwent ERAS. The demographics of these 2 groups were comparable. 14.74% non-ERAS patients (n = 14) developed parastomal hernias compared to 34.51% (n = 39) in the Enhanced Recovery group (p = 0.0011). <h3>Conclusion</h3> This study demonstrated a significantly increased incidence of parastomal hernias in those undergoing enhanced recovery, consistent with the earlier postoperative mobilisation. While the other benefits of ERAS outweigh this risk, this reality of modern post-operative care should reinvigorate the use of scrupulous surgical technique, and consideration of stoma site reinforcement options. <h3>Disclosure of interest</h3> None Declared. <h3>References</h3> Gravante G, Elmussareh M. Enhanced recovery for colorectal surgery: practical hints, results and future challenges. World J Gastrointest Surg. 2012;4(8):190–8 Chestovich PJ, Lin AY, Yoo J. Fast-track pathways in colorectal surgery. Surg Clin North Am. 2013;93(1):21–32 Lv L, Shao YF, Zhou YB. The enhanced recovery after surgery (ERAS) pathway for patients undergoing colorectal surgery: an update of meta-analysis of randomized controlled trials. Int J Colorectal Dis. 2012;27(12):1549–54 Abraham N, Albayati S. Enhanced recovery after surgery programs hastens recovery after colorectal resections. World J Gastrointest Surg. 2011;3(1):1–6 Godbout JP. Glaser R. Review Stress-induced immune dysregulation: implications for wound healing, infectious disease and cancer. J Neuroimmune Pharmacol. 2006;1(4):421–7 Boyapati L, Wang H. Review the role of stress in periodontal disease and wound healing. Periodontol 2000. 2007;44:195–210 Hotouras A, Murphy J, Thaha M, Chan CL. The persistent challenge of parastomal herniation: a review of the literature and future developments. Colorectal Dis 2013;15(5):e202–14 Sohn YJ, Moon SM, Shin US, Jee SH. Incidence and risk factors of parastomal hernia. J Korean Soc Coloproctol 2012;28(5):241–6

A multicriteria experimental analysis of impact on fiber reinforced polymer composite laminates

The use of fiber reinforced polymers (FRPs) is rapidly increasing in air, land, and marine manufacturing sectors. This is despite the fact that a universal methodology has not been yet developed to assist designers in selecting optimum reinforcing fiber architectures under different loading scenarios. The focus of the present article is to recommend a systematic approach for selecting the architecture of long-fiber fabric reinforcements in FRP composite structures under impact events. Namely, nine design criteria were selected and quantified for four types of PP/glass laminates through drop tower impact testing under 200J energy, four-point flexural bending before and after impact, as well as microtomographic damage analysis of impacted samples. Subsequently, ranking of the candidate laminates was found using a multiple criteria decision making (MCDM) technique to aid in selecting the overall best performing fiber reinforcement option under the presence of conflicting and inter-dependent design attributes.

The use of autologous fascia lata graft in the laparoscopic reinforcement of large hiatal defect: initial observations of the surgical technique.

BackgroundEven though there is no consensus, many authors believe that in the cases of large hiatal defects, structurally altered crura and/or absence of peritoneal lining, a crural reinforcement should be performed. Reinforcement could be performed with different techniques and different type of mesh, either synthetic or biologic. The disadvantages of mesh repair include the possibility of serious complications and increased costs especially in the usage of composite or biologic mesh.MethodsThe study includes 10 cases of reinforced primary suture line of the pillars with autologous fascia lata, in elective laparoscopic repair of the giant PEH with a large hiatal defect and friable crura. After intraopreative confirmation of the large hiatal defect (hiatal surface area of more than 8 cm2) and friable crura, an autologous fascia lata graft was harvested in the usual manner and placed in on-lay fashion to reinforce the pillar suture line. We analyzed surgical technique, complications, and initial follow-up of the patients.ResultsAverage hiatal surface area (HSA) in our series was 10.6 cm2 (range 8.1 to 14.4 cm2). The average duration of operation was 203.9 min/3.4 hours (range 160–250 min). Except for a mild hematoma in the harvesting region that resolved spontaneously, there were no procedure related complications and 30 days mortality rate was zero. The average postoperative length of stay was 6.5 days (5–8 days). Out of 10 patients, 5 completed the annual follow-up visit, while 8 completed a 6- month follow-up visit. So far there is no hernia recurrence and/or problems with swallowing function. However, one patient has felt a mild discomfort in the harvested region that does not influence normal daily activities.ConclusionsAutologous fascia lata graft hiatal reinforcement represents a technically feasible, easy, and available option for the on-lay reinforcement of large hiatal defects with friable crura in the laparoscopic repair of giant PEHs.

Earthen masonry dwelling structures for extreme wind loads

Earthen masonry made of compressed and stabilized earth blocks (CSEBs) is emerging as a sustainable and locally appropriate construction material for affordable high-quality dwellings. Compelling features include the local availability and affordability of suitable soils, thermal insulation and humidity control properties, and small embodied energy compared with fired clay masonry. The mechanical properties of CSEBs have been the subject of several investigations. However, the research on the response and design optimization of CSEB masonry building structures is in its infancy, and a significant knowledge and technological gap exists with regard to resistance to extreme loads due to natural hazards (e.g., high winds and earthquakes). It is necessary to address this gap to understand whether engineered earth masonry can be enlisted to respond to the growing demand for hazard-resistant dwellings that are also affordable and sustainable.This paper discusses the feasibility of using earth masonry in low-rise dwelling structures to withstand extreme winds. Hurricanes and tornadoes periodically scourge vast areas in Central and North America and the Caribbean where low-income families live, and where the demand for sustainable construction meets that for structural resistance and affordability. Feasibility is studied based on the structural analysis of the main wind force resisting system (MWFRS) of a typical one-story single-family dwelling subject to wind pressures resulting from 3-s gust speeds up to 90m/s (324km/h). The output consists of parametric curves that relate wind speed with masonry compressive, tensile and shear strength demand for wall thicknesses ranging from 203 to 508mm. The structural adequacy of the MWFRS is assessed for the cases of flat and 15° gable roof. The design implications are discussed vis-à-vis strength reduction factors and design strength demands, and sustainable reinforcement options. It is concluded that it is feasible to design one-story CSEB masonry dwellings that can withstand winds loads from Category 4 hurricanes and EF3 tornadoes, provided that a rigid horizontal diaphragm is used. Grouted steel reinforcement may be used in safety shelter CSEB masonry structures to be designed for more extreme wind loads.

Parastomal hernia repair and reinforcement: the role of biologic and synthetic materials.

Parastomal hernia is a prevalent problem and treatment can pose difficulties due to significant rates of recurrence and morbidities of the repair. The current standard of care is to perform parastomal hernia repair with mesh whenever possible. There exist multiple options for mesh reinforcement (biologic and synthetic) as well as surgical techniques, to include type of repair (keyhole and Sugarbaker) and position of mesh placement (onlay, sublay, or intraperitoneal). The sublay and intraperitoneal positions have been shown to be superior with a lower incidence of recurrence. This procedure may be performed open or laparoscopically, both having similar recurrence and morbidity results. Prophylactic mesh placement at the time of stoma formation has been shown to significantly decrease the rates of parastomal hernia formation.

Concurrent access to nicotine and sucrose in rats.

Animal models that allow concurrent access to drug and nondrug reinforcers provide unique insight into the etiology, maintenance, and treatment of drug use. We sought to develop and utilize a concurrent access procedure with nicotine and sucrose in rats. Pressing one lever delivered intravenous nicotine, and pressing another lever delivered sucrose pellets, with both reinforcers freely available throughout daily sessions. Rats that had been pretrained with nicotine on some days and sucrose on other days responded on both levers when subsequently given concurrent access, but almost all responded at substantially higher rates on the sucrose lever. In contrast, rats pretrained exclusively with nicotine before being given concurrent access showed individual differences, with about half responding more on the nicotine lever. Treatment with the nicotinic receptor partial agonist varenicline selectively decreased nicotine self-administration. Food restriction and removal of the sucrose lever both increased nicotine self-administration. The finding that rats continue to take nicotine when sucrose is concurrently available-and in many cases take it more frequently than sucrose-demonstrates that nicotine self-administration does not only occur in the absence of alternative reinforcement options. As a model of human nicotine use, concurrent access is more naturalistic and has higher face validity than procedures in which only one reinforcer is available or choosing one reinforcer precludes access to other reinforcers. As such, this procedure could be useful for evaluating therapeutic agents and improving our understanding of environmental conditions that promote or discourage nicotine use.

Comparison of laparoscopic sleeve gastrectomy leak rates in four staple-line reinforcement options: a systematic review

ObjectiveThe study compared laparoscopic sleeve gastrectomy (LSG) staple-line leak rates of 4 prevalent surgical options: no reinforcement, oversewing, nonabsorbable bovine pericardial strips (BPS), and absorbable polymer membrane (APM). BackgroundLSG is a multipurpose bariatric/metabolic procedure with effectiveness proven through the intermediate term. Staple-line leak is a severe complication of LSG for which no definitive method of prevention has been identified. MethodsThe systematic review study design was employed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement screening guidelines. Inclusion criteria centered on variables potentially relevant to LSG leak: leak rate, age, gender, calibrating bougie size, distance between pylorus and gastric transection line, overall complication rate, and mortality. Analysis of variance models were used to explore differences in select demographic and surgical technique variables characterizing each reinforcement group. An omnibus χ2 test followed by independent Fisher’s exact tests were used to compare leak rates. ResultsThere were 659 articles identified; 41 duplicates removed. Of 618 remaining articles, 324 did not meet inclusion criteria. Of the 294 remaining articles, 206 were eliminated (kin studies, those not reporting staple-line or leak incidence, those reporting discontinued products). There were 88 papers included in the analysis. Statistically significant differences were found between groups across demographic and surgical variables studied (p<0.001). There were 191 leaks in 8,920 patients; overall leak rate 2.1%. Leak rates ranged from 1.09% (APM) to 3.3% (BPS); APM leak rate was significantly lower than other groups (p< 0.05). ConclusionSystematic review of 88 included studies representing 8,920 patients found that the leak rate in LSG was significantly lower using APM staple-line reinforcement than oversewing, BPS reinforcement, or no reinforcement.

Similar key posture transformation based on hierarchical Option for humanoid robot

Concerning the problem in which the fixed locomotion track captured from human movement can not be used in transformation between key postures for humanoid robot,a method of similar key posture transformation based on hierarchical Option for humanoid robot was proposed.The multi-level dendrogram of key postures was constructed and the difference of key postures was illustrated in respects of similar joint difference,moment total similar difference,period total similar difference.The hierarchical reinforcement Option learning was introduced,in which the sets of key postures and Option actions were constructed.SMDP-Q method tended to be the optimal Option function by the accumulative rewards of key posture difference and the transformations were realized.The experiments show the validity of the method.

Parameterisation of Gypsum Mortar for Alternative Structural Consolidation of Traditional Floors

The role of gypsum as a construction material in vernacular architecture, not only as an auxiliary material, but also for enhancing structural features in floors and even in pillars, has had a long-standing history of application in different traditional buildings in some parts of Spain. The authors have identified the main properties of this material from a structural point of view by experimenting in situ on traditional gypsum jack arch floors as part of the project “Structural consolidation of traditional floors with compression layers of gypsum with fibres” (UPV/PAID-05-11/2893). Several traditional and commercial compression layers for traditional floors were made with different proportions of water in the mixture to parameterise its use and achieve the ideal thickness and dosage. In this research, the authors have used both traditional dosages and experimental mixtures containing fibres, which were monitored by standard tests of surface hardness and resistance to compression and flexion. This work presents the main results of the properties of the different types gypsum obtained in the laboratory analysis phase as an alternative option for the structural reinforcement of traditional floors.

노천광 연약 사면에서의 계측시스템 선택을 위한 고찰

노천광산에서 사면설계는 안정성과 경제성 측면에서 동시에 접근하여 결정해야 한다. 또한 일반 도로 사면과 달리 대부분 보강 없이 굴착해야 하기 때문에 사면경사가 가장 중요한 설계 변수이다. 본 연구에서는 인도네시아 Pasir 광산의 Roto South 채탄장에 대한 사면 변위계측, 계측자료의 해석 및 수치해석을 통해 사면의 거동을 감시하기 위한 계측 시스템을 제안하고자 한다. Pasir 광산의 경우 관리해야할 사면의 영역이 매우 광범위하고, 수치해석에 의한 예상 변위량은 최대 3,000 mm 정도로 나타났다. 현장에서 수행된 경사계에 의한 계측 및 GPS에 의한 변위 계측에 대한 검토와 자동화를 위한 SSR (slope stability radar system)의 적용에 대해 검토하였다. The slope design of an open-pit mine must ensure slope stability and economic feasibility. The overall slope angle of the pit is therefore the main factor of concern because of limited support or reinforcement options available in such a setting. This study examines the optimal measurement system for monitoring the behavior of the slope in an open-pit mine using displacement measurement, data analysis, and numerical simulations for a coal mine at Pasir, Indonesia. The area of slope to be managed is extensive and the maximum displacement, as calculated by numerical analysis, is about 3,000 mm. The displacement data, measured by inclinometer and GPS, were analyzed, and the applicability of SSR (slope stability radar) was reviewed in comparison with other monitoring systems.

Investment Analysis of Network Reinforcements Mix for Distribution Systems with Distributed Generations

New trends of environmental, regulation, and economical aspects cause an increasingly distributed generation (DG) connected to distribution networks. Existing distribution networks, however, are not designed to accept extensive DG. Many novel network reinforcement approaches have been proposed for solving the network connection issues. For economic viewpoints, it is important for determining cost-effective network reinforcement solutions for facilitating the meeting of DG growth goals while maintaining the network supply quality and operation security. This paper aims to address network reinforcements investment analysis for accommodating DG capacity growth. A methodology is proposed in this approach to quantify the impact of future increases in DG through the undertaking of a case study based on a generic distribution network model and different projected DG scenarios. Some available network reinforcement options used for managing fault level, voltage level, and power flows are presented and their costs required for meeting supply quality requirements of different types of customers are analyzed. Test results of applications of the proposed method to a practical distribution system are presented. Analysis results can assist distribution network operators in determining proper reinforcement options for managing distributed energy resources.

Bronchial stump reinforcement with an azygous vein flap

Bronchial stump reinforcement has been shown to significantly reduce the incidence of bronchopleural fistulas. Various coverage techniques have been described in the literature. While the azygous vein flap is an easy, safe and effective reinforcement option for right-sided bronchial stumps, the flap is not widely adopted, with little mention in the literature, partly due to surgeons' uneasiness with the technique. In this report, we describe an easy-to-adopt approach to azygous vein bronchial reinforcement.

Planning and Operational Issues Arising From the Widespread Use of HTLS Conductors

High-temperature low-sag (HTLS) conductors, which can double the ampacity of conventional conductors, are becoming a mature option to uprate thermally limited transmission lines. This paper addresses several issues related to the widespread use of HTLS conductors in existing power systems. The first part of the paper analyzes the influence of higher line resistances on power transfer capability as well as the accuracy of conventional network models, based on constant conductor temperatures. The second part deals with the problem planners are facing when considering existing network reinforcement options versus the new alternative offered by HTLS conductors, intended to replace Alloy Aluminum Conductor Steel Reinforced (ACSR) equipment in situ. This leads to a security-constrained optimization problem involving binary decision variables. The 57-bus system is used throughout the paper to illustrate the main ideas.

Optimal Electrical Distribution Systems Reinforcement Planning Using Gas Micro Turbines by Dynamic Ant Colony Search Algorithm

Distribution systems management is becoming an increasingly complicated issue due to the introduction of new energy trading strategies and new technologies. In this paper, an optimal reinforcement strategy to provide reliable and economic service to customers in a given time frame is investigated. In the new deregulated energy market and considering the incentives coming from the political and economical fields, it is reasonable to consider distributed generation (DG) as a viable option for systems reinforcement. In the paper, the DG technology is considered as a possible solution for distribution systems capacity problems, along several years. Therefore, compound solutions comprising the installation of both feeders and substations reinforcement and DG integration at different times are considered in the formulation of a minimum cost distribution systems reinforcement strategy problem. An application on a medium size network, hypothesizing a scenario of reinforcement also using as DG gas micro-turbines, is carried out using a novel optimization technique allowing the identification of optimal paths in trees or graphs. The proposed technique is the Dynamic Ant Colony Search algorithm

Development Length of Glass Fiber-Reinforced Polymer Bars in Concrete

Glass fiber-reinforced polymer (GFRP) reinforcing bars have become a viable option for reinforcement in concrete when corrosion is a concern. The objective of this research was to investigate the bond performance of GFRP reinforcing bars in concrete, to evaluate the existing ACI Committee 440 recommendations for development length of FRP bars in concrete, and to develop new design recommendations if needed. An equation for the development length of GFRP reinforcing bars in concrete was formulated by applying a methodology similar to one used to create the development length equation for steel reinforcing bars. Data collected from beam-based bond tests in the literature were used to construct two equations for development length: one based on a splitting mode of failure and the other on a pullout mode of failure. The effects of bar diameter, bar tensile strength, concrete compressive strength, cover, and the presence of transverse reinforcement were investigated. The proposed equations appear to be a conservative yet reasonable means to calculate the development length of GFRP reinforcing bars in concrete given the available test data. The proposed equations are compared to those found in ACI 440.1R-03 and the Japanese Design Guidelines.

Reliability-performance-index probability distribution analysis of bulk electricity systems

System reliability performance is usually based on average customer-interruption indices. The average values are valuable information, but provide only a single customer risk dimension without the underlying probability distributions. The average annual indices give no insight as to how reliability may vary from year to year as a result of the random behaviour of a bulk electric system. Reliability-index probability distributions, therefore, provide additional valuable information and a more complete understanding of composite power system behaviour. A significant advantage when utilizing sequential Monte Carlo simulation in bulk electric system reliability analysis is the ability to provide reliability-index probability distributions in addition to the expected values of their indices. This paper illustrates the development of probability distributions for bulk electric system reliability performance indices using sequential simulation. The results obtained using the developed software show that the system performance-index probability distributions have unique characteristics that are basically dependent on the system topology, operating philosophy and conditions. System conditions such as the peak load level and system reinforcement options have significant impacts on the performance-index probability distribution characteristics. The basic concepts and their application in composite power system reliability evaluation are illustrated by application to a small practical test system.

How We Do It: Keeping paediatric patients motivated during the cochlear implant rehabilitative process

Cochlear implantation of very young children is a daunting prospect for the clinicians who must program, or map, their speech processors, or who provide other rehabilitative services. The limited communication skills, short attention span and non, compliant behaviour of young children challenge the most seasoned and skilled rehabilitation professionals. This article reviews some of the techniques that can be utilized to increase the likelihood of successful rehabilitation sessions. These techniques involve the structure of the rehabilitation sessions themselves, the selection of developmentally appropriate materials and procedures, and reinforcement options. The article also includes some specific activities designed to maintain a child’s interest over a prolonged period of time.