bluuebunny/crossref_metadata_2025 huggingface dataset:
Distrust: Not Only in Secret Service Organizations
Authors: Siebert Sabina , Czarniawska Barbara
Published: September 2018

In this article, we discuss the issue of distrust in the most extreme example of distrustful organizations: secret service organizations. Distrust may be a basic organizing principle in such organizations, but how is it produced and maintained? Inspired by actor–network theory, we analyzed the devices, codes, rules, and procedures used in secret service organizations, and then asked whether these devices, codes, rules, and procedures differ from those used in ordinary organizations. Based on our analysis, we make two contributions. First, we draw researchers’ attention to distrust that is intentionally built and maintained rather than distrust that is accidental and indicative of faulty management. Second, we identify the material manifestations of distrust. We argue that in future studies of trust and distrust in organizations, it will be necessary to focus on the technologies, physical objects, and quasi-objects. These, together with discourses, guarantee the stability of connections among organizational actions.
Surviving in the Plastics Recycling Industry
Authors: Hornberger Lee
Published: September 2018

Rising resin prices and decreasing landfill availability accelerated the expansion of the consumer plastics recycling industry in the 1980's. Unfortunately, many of the recycling companies that were started during this optimistic time quickly learned that economic recycling of post-consumer waste was extremely difficult and they went out of business. Those recycling companies that survived managed to develop stable technologies and markets for their products. These businesses are models for their industry as well as for the emerging automotive and electronic plastics recycling industry.

In this study, the annual sales, experience, markets, growth strategies, technology and leadership of 36 recycling firms were evaluated to determine the characteristics that helped these companies survive in this difficult industry. These recycling firms were located in the United States and in Europe. Four elements were found to be present in most of the surviving companies: a) a willingness to adapt to changes in the marketplace b) extensive knowledge of recycling technology c) financial and technical support and d) strong internal leadership.
Literature Review Prevention and Reduction of Plastic Waste in European Automotive Producers
Authors: Jimenez Alexis Baltazar y
Published: September 2018

This paper discusses the issue of plastic recycling in the European automotive industry, specifically the plastic waste generated through end-of-life vehicles (ELV). It also explores the existing relationship between engineering materials selection, and what are considered to be the critical issues currently present in the automotive recycling field.

Research found that although a new set of recycling technologies has been developed, an increase in the protection of the environment might end in reduced margins for the automobile manufacturers, in addition to a rise in the costs of recycling.
Development of Adhesive Compositions Using Powder Coating Residues
Authors: Ana M.C. Grisa , Freire Estevão , Aguzzoli Cesar , Zeni Mara
Published: September 2018

The industry of powder coatings, for base polyester/epoxy, produces about 300 kg.day−1 of residue in a production of 6,000 kg.day−1 (5% residue). Powder coatings with equal or lower to 10 μm of granulometer are considerate residues. The use of these residues in the formulation of adhesives is studied in the present work. Portions of residue with 0.1 a 0.5 g.mL−1 were tested with 7 solvents and 5 kinds of elastomers. Two solvents compatible with the residue and three elastomers, so, three mixtures were obtained: A, B and C; then, 15 g of a petroleum derivated was additioned. The mass of mixtures was homogenized in a mechanic stirrer for 15 minutes. The preliminary tests have demonstrated that the adhesives A, B and C had effective adherence in carpet on cement slab and HDF® (High Density Fiber). The formulations of A, B and C show superior to other 8 tested specially in: fast drying, migration of adhesive upon the surface (carpet) and adherence to the slab. According to the rules ASTM D2094 and D2095 the results of tension test are compared to commercial adhesives, resulting that adhesive C had an efficiency similar to a commercial adhesive for the same utilization.
Environmental Aspects of Mechanical Recycling of PE and PET: A Life Cycle Assessment Study
Authors: Perugini Floriana , Mastellone Maria Laura , Arena Umberto
Published: September 2018

The quantification of the actual environmental advantage of mechanical recycling of post-consumer PET and PE liquid containers was the main aim of the study. The phases of collection, compaction, sorting, reprocessing and refuse disposal in the Italian system of plastic packaging waste recycling were individually analysed and quantified in terms of energy and material consumptions as well as of emissions in the environment.

The results indicate that the recycling scenarios are always preferable to those of non-recycling. The energy saving could be as large as 185% if the energy recovery from scrap wastes is realised. The reduction in material consumption is even very large, indicating, for instance, that in only one year the Italian system for plastic liquid containers is able to save more than 83,000t of crude oil, 28,000t of gas and 23,000t of coal. The calculations were made with the (reasonable) assumption that the final utilization can use the virgin or the recycled polymer without any difference.
Development of Organic Semiconductors for Optoelectronic Applications from Pre-Vulcanised Natural Rubber Latex
Authors: Predeep P. , Sreeja R. , Alex R. , Sharma P.D.
Published: September 2018

In this paper we demonstrate for the first time that pre-vulcanized NR latex can be doped by iodine to become electrically conducting. The study reveals that pre-vulcanisation will not hinder the formation of conjugated sequences, which is widely accepted as a prerequisite for developing intrinsic electrical conductivity in polymers. The samples in thin film form and in solution showed the characteristic colour change on doping and the conductivities were at par with iodine-doped unvulcanised rubber. The resulting structural changes were further confirmed by UV/Vis and FTIR measurements. These strong vulcanized films can ensure fairly good flexibility and processability in coalition with conductivity. The band gap of this conducting latex film was evaluated to be 1.38eV. These findings are of far-reaching consequences for the rubber industry, as it is now possible to develop interpenetrating rubber composites for bulk polymer heterojunctions for use in microelectronics. Doped vulcanized NR latex promises to be a cost effective and highly efficient material for use in solar cells and light emitting diode materials.
The Effect of Waxes on Rubber Vulcanisates
Authors: Agrawal S.L. , Mandot S. , Bandyopadhyay S. , Mukhopadhyay R. , Deuri A.S.
Published: September 2018

Certain substances like wax, when incorporated into rubber vulcanisates during mixing prior to vulcanisation are able to bloom and form a surface layer with significant importance in appearance and in protection against ozone. In tyres, this is particularly important in sidewall compounds as ozone protection reflects in its storage, both under static and dynamic conditions, and appearance plays an important role in determining acceptance in today‘s competitive market.

In this paper, the effect of different waxes and their blends on the properties of sidewall compounds with varying natural rubber/butadiene rubber ratios, is reported. It was found that blends of paraffin and microcrystalline waxes with specific carbon chain distributions resulted in optimum properties.
Effect of Phenol-CNSL Formaldehyde Copolymer on Thermal Ageing of NBR
Authors: Mary Lubi C. , Thachil Eby Thomas
Published: September 2018

Cashew nut shell liquid (CNSL) is a cheap agro-by-product and renewable resource which consists mainly of substituted phenols. A CNSL based resin was used in this study to modify the aging properties of butadiene-acrylonitrile rubber (NBR). The resin was a copolymer obtained by condensing a mixture of phenol and CNSL with hexamethylene tetramine. The effect of the resin on the ageing of NBR vulcanizates was studied by following changes in tensile strength, elongation at break, modulus and tear strength.

Resins with different phenol/formaldehyde ratios and CNSL/phenol ratios were incorporated into NBR and the physical properties determined. Comparison of the properties of the aged material containing the CNSL resin with those of specimens not containing the resin show improved ageing characteristics with respect to tensile strength, modulus and tear strength.
Effect of SEBS on the Mechanical Properties and Miscibility of Polystyrene Rich Polystyrene/ Polypropylene Blends
Authors: Samsudin Sani Amril , Hassan Azman , Mokhtar Munirah , Jamaluddin Syed Mustafa Syed
Published: September 2018

Blends of polystyrene (PS) with polypropylene (PP) are usually developed to overcome the inherent brittleness of PS. However, PS with PP are immiscible and (in the absence of a compatibiliser) incompatible. The present study investigated the effects of styrene-b (ethylene-co-butylene)-b-styrene (SEBS) on the mechanical properties and compatibility of PS-rich PS/PP blends. Using a Brabender PL2000 twin-screw extruder, blends of PS/PP in various compositions ranging from 100-60 wt% PS with and without SEBS were prepared and injection moulded. The overall results clearly showed that the mechanical properties of PS/PP blends are dependent on blend composition (ratio of PS/PP) and SEBS content. The impact strength and elongation at break of the PS/PP blends increase with SEBS content, at the expense of tensile strength and flexural modulus. The improvements in impact strength and elongation at break with the addition of SEBS are due to the improved interfacial adhesion between the dispersed phase (PP) and matrix phase (PS).

The improvement in miscibility of the PS/PP blend with the addition of SEBS is supported by DMA analysis. This showed that the 60/40 PS/PP blends possess two endothermic peaks whereas 60/40/25 PS/PP/SEBS blends have a single endothermic peak at 102 °C, indicating that they have an improved miscibility.

The effectiveness of SEBS in enhancing the blends depends on the blend composition. A significant improvement was observed upon addition of more than 10 phr of SEBS into the 70/30 and 60/40 PS/PP blends, but not much improvement in the case of the 90/10 and 80/20 PS/PP blends. However, a higher SEBS content is more effective at higher PS contents, as illustrated by the 90/10/25 PS/PP/SEBS blends having higher impact strengths than 60/40/25 PS/PP/SEBS. The optimum blend, based on achieving a balance between toughness (impact strength) and stiffness (flexural modulus), is 90/10/25 PS/PP/SEBS, followed by 80/20/25 PS/PP/SEBS.
Compatibilisation of Heterogeneous Styrene Butadiene Rubber/Poly(Ethylene-co-vinyl Acetate) Blends
Authors: Radhakrishnan C. K. , Padmini M. , Sujith A. , Unnikrishnan G.
Published: September 2018

The compatibilisation of styrene butadiene rubber (SBR) and poly(ethylene–covinyl acetate) (EVA) blends with maleic-anhydride grafted poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS-g-MA) triblock copolymer has been investigated. The introduction of SEBS-g-MA resulted in an improvement in the mechanical properties of the blends with a reduction in damping characteristics, indicating the presence of efficient interfacial bonding. The optimum loading of SEBS-g-MA for SBR/EVA blends, has been found to be 6 phr. The better mechanical performance has been observed to be achieved for the compatibilised blends with DCP as curing agent. The results have been complemented by the studies using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). It has also been found that the compatibilisation with SEBS-g-MA improved the thermal ageing characteristics of SBR/EVA systems.
Effect of Re-Compounding on the Properties of Polypropylene / Wood Flour Composites
Authors: Viksne A. , Rence L.
Published: September 2018

Two different mixers were used for re-compounding of wood flour / polypropylene composites (WPC): internal Banbury mixer and co-rotating twin-screw extruder. Five cycles in an internal mixer and twelve cycles in an extruder were performed on WPC in order to compare the properties of composites. After 3 cycles in an internal mixer, an increase of the WPC mechanical properties (tensile, flexural and impact strength) and a decrease of water uptake was observed. Further increase of the number of cycles in an internal mixer leads to a significant decrease of WPC properties, as long as the properties remain unchanged, if reprocessing was done in extruder. More significant degradation of WPC occurred in an internal mixer compared to the extruder, therefore only 10% of the recyclate prepared in the Banbury mixer and 30% of the recyclate prepared in the extruder can be added to virgin WPC without a decrease of its properties.
Paints Based on Waste Expanded Polystyrene
Authors: Myint S. , Zakaria M.S.B. , Ahmed K.R.
Published: September 2018

A formula for making paint was developed using waste expanded polystyrene foam (EPS) as a binder. This method replaces the alkyd resin in most commercial paint, which is derived from the byproducts of refining crude oil. Experimental results showed that 27% waste polystyrene foam can be incorporated in the paint formulation. Basic performance tests for EPS paint were conducted and evaluated, and the developed formulation was compared with commercial paint containing modified alkyd resin as a binder. Test results showed that EPS-based paint has some advantages such as excellent abrasion resistance, water resistance, alkali resistance, hardness, and adhesion characteristics.
Morphology and Properties of Injection-Moulded Recycled Poly(Ethylene Terephthalate)/Poly(Ethylene Octene) Blends
Authors: Liu Yongjun , Su Zhizhong , Guo Weihong , Li Binyao , Wu Chifei
Published: September 2018

Recycled poly(ethylene terephthalate) (r-PET) was blended with poly(ethylene octene) (POE) and glycidyl-methacrylate-grafted poly(ethylene octene) (mPOE). The morphology and thermal properties of injection-moulded blends through the thickness of impact specimens were investigated. A remarkable difference was found in the through-thickness morphology and thermal properties of the injection-moulded blends. The three-layered structure (namely the skin, subskin, and core layers) showed a hierarchical structure. Scanning electron microscopy showed that the orientation of the dispersed-phase particles in the skin and subskin layers was much higher than that in the core layer. Differential scanning calorimetry indicated that the skin and core layers had the same component content, but the core layer had a higher degree of crystallinity than the skin layer.
Properties of Recycled LDPE/Birch Fibre Composites
Authors: Twite-Kabamba Eddy , Fehri Zineb Fassi , Rodrigue Denis
Published: September 2018

This study investigates how the properties of a wood polymer composite are modified by recycling, especially how the presence of fibres modify polymer degradation. To this end, low density polyethylene was selected as the matrix and yellow birch fibres as the reinforcement. The effect of recycling was simulated via closed-loop reprocessing of the material up to ten times under constant extrusion conditions. For each generation, thermal, rheological and morphological measurements were combined with macromolecular investigations including the complete molecular weight distribution of the polymer. The results revealed that polymer crystallinity increased with the number of composite regeneration, while the zero-shear viscosity decreased with recycling. Elongational rheology also revealed that the behaviour of the polymer changed from strain hardening to strain softening for the composite. From the morphological analysis, a degradation severity coefficient was defined to characterize the impact of operating conditions on fibre length. Finally, macromolecular investigations showed that the number-average molecular weight (Mn) of the polymer was more affected than the weight-average molecular weight (Mw). The relative branching factor and the branching frequency were also modified by the effect of reprocessing with and without the presence of wood fibre.
Effect of Storage on the Colloidal Properties of Room-temperature Prevulcanised Natural Rubber Latex
Authors: Palaty S. , Devi P.V. , Honey J.
Published: September 2018

This paper reports on the study of the prevulcanisation of natural rubber latex (NRL) at room temperature. NRL was prevulcanised at room temperature using a zinc butyl xanthate [Zn(bxt)2]–zinc diethyl dithiocarbamate [ZDC] accelerator system. High-temperature (55–60°C) prevulcanisation of NRL was also done using the conventional accelerator system. Effect of storage on the colloidal properties of room-temperature prevulcanised latex was studied up to 30 days, and these properties were compared with those of conventional high-temperature prevulcanised latex. The colloidal properties were found to be superior for the room-temperature prevulcanised latex. The mechanical stability time (MST) of room-temperature prevulcanised latex increases on storage. The room temperature prevulcanised latex is found to be stable for 30 days of storage.
Conceptualizing and Creating Sustainable Careers
Authors: McDonald Kimberly S. , Hite Linda M.
Published: September 2018

The world of work continues to change, with potentially dire predictions for the future as technology, work intensification, and workplace inequities impinge on careers, suggesting a need for increased attention on how to sustain them. This article focuses on the concept of sustainable careers: what they are, why they matter now, and what other disciplines are doing to address this phenomenon. The authors conclude with how human resource development can play a significant role in research and practice to develop both systems that foster career sustainability and individuals who are ready to embrace an evolving career climate.
Research on the city tram collision at a level crossing
Authors: Zhou Hechao , Zhang Chao , Zhan Jun , Zhang Jimin
Published: September 2018

The collision simulation between a city tram and a car at a level crossing is carried out based on the multi-body dynamics. Compared with the finite element method, this method has an obvious advantage of fast computation speed, so that it is convenient for the study on the dynamic responses and derailment mechanism of railway vehicles during a collision accident. The simulation results show that when a city tram is laterally impacted by a car at a level crossing, the dynamic response and the derailment risk of the collided city tram are greatly influenced by the boundary conditions, such as the mass and speed of the colliding car, the structural arrangement and the loading condition of the city tram. Moreover, in terms of the space limitation of the city tram, two measures are proposed to decrease the lateral impact force during its transition from car body to wheel set. One is to use the secondary damper and the other is to increase the secondary lateral clearance. The simulation results point out that the derailment coefficient of the improved city tram can be reduced by 52%, from 1.63 to 0.79.
Oesophageal symptoms are common and associated with other functional gastrointestinal disorders (FGIDs) in an English‐speaking Western population
Authors: Josefsson Axel , Palsson Olafur , Simrén Magnus , Sperber Ami D , Törnblom Hans , Whitehead William
Published: September 2018

Background

The prevalence and frequency of oesophageal symptoms suggestive of a functional oesophageal disorder according to the Rome IV criteria are unknown.

Objective

We aimed to describe the prevalence and risk factors for oesophageal symptoms compatible with functional oesophageal disorders in the general population.

Methods

Data were analysed from a population‐based online survey of 6300 individuals aged ≥ 18 years in the USA, UK and Canada with equal demographic proportions across countries. Questions included the Rome IV diagnostic questionnaire, demographics, medication, somatization, quality of life, and organic gastrointestinal (GI) disease. Multivariate analysis was used to identify factors independently related to oesophageal symptoms.

Results

Data from 5177 participants (47.8% female; mean age 46.7 years) were available for analysis. Symptom prevalence was 8.1% for globus, 6.5% for heartburn, 4.5% for dysphagia and 5.2% for chest pain, and 17.0% reported at least one oesophageal symptom. Oesophageal symptoms were independently associated with younger age, female gender, previous abdominal surgery and the presence of other functional GI disorders. Reporting oesophageal symptoms was associated with reduced quality of life.

Conclusion

Oesophageal symptoms are common in the general population and important predictors include other functional GI disorders, age and gender. Oesophageal symptoms are associated with poorer quality of life.
Analysis of Publication Trends for the 2011-2015 American Orthopaedic Society for Sports Medicine Annual Meeting Abstracts
Authors: Gowd Anirudh K. , Liu Joseph N. , Cabarcas Brandon C. , Cvetanovich Gregory L. , Garcia Grant H. , Verma Nikhil N.
Published: September 2018

Background:

Academic conferences are sources of novel research that can influence clinical decision making. Orthopaedic surgery maintains a relatively high rate of publication compared with other surgical subspecialties, and sports medicine conferences hold an even higher rate within the subspecialty. The American Orthopaedic Society for Sports Medicine (AOSSM) annual meetings have been shown to have among the highest rates of publication for accepted abstracts.

Purpose:

To determine differences between 2-year publication rates of poster and podium abstracts accepted into the AOSSM annual meetings and identify factors associated with publication.

Study Design:

Cross-sectional study.

Methods:

The AOSSM archives were queried for all accepted poster and podium presentations for annual meetings from 2011 through 2015. Google Scholar and MEDLINE databases were used to determine which abstracts transitioned into journal articles. Publication rates were compared based on publication 2 years following presentation. Logistic regression was performed to demonstrate which variables were most correlated with successful publication. Data on publication impact factor and number of citations were collected by use of the InCites database.

Results:

Of 628 abstracts accepted during this period, 265 were poster presentations and 363 were podium presentations. Overall, 44.7% of abstracts presented were accepted into peer-reviewed journals within 2 years of presentation. No statistical difference was found between poster and podium presentations for journal publication ( P = .328). Poster presentations were published in journals with statistically lower impact factor ( P = .005) and had a statistically lower number of citations ( P < .001) compared with podium presentations. Multivariate logistic regression analysis demonstrated that only number of authors was correlated with publication ( P = .003).

Conclusion:

Podium and poster presentations accepted into AOSSM conferences had equal rates of publication within 2 years and should influence decision making equally. The relative impact of podium presentations appeared to be greater, which suggests that the AOSSM selects podium presentations that will have greater clinical impact. Increasing number of coauthors was the only factor found to be correlated with publication.
The Expression of Aldolase B in Islets Is Negatively Associated With Insulin Secretion in Humans
Authors: Gerst Felicia , Jaghutriz Benjamin A , Staiger Harald , Schulte Anke M , Lorza-Gil Estela , Kaiser Gabriele , Panse Madhura , Haug Sieglinde , Heni Martin , Schütz Monika , Stadion Mandy , Schürmann Annette , Marzetta Flavia , Ibberson Mark , Sipos Bence , Fend Falko , Fleming Thomas , Nawroth Peter P , Königsrainer Alfred , Nadalin Silvio , Wagner Silvia , Peter Andreas , Fritsche Andreas , Richter Daniela , Solimena Michele , Häring Hans-Ulrich , Ullrich Susanne , Wagner Robert
Published: September 2018

Context

Reduced β-cell mass, impaired islet function, and dedifferentiation are considered causal to development of hyperglycemia and type 2 diabetes. In human cohort studies, changes of islet cell–specific expression patterns have been associated with diabetes but not directly with in vivo insulin secretion.

Objective

This study investigates alterations of islet gene expression and corresponding gene variants in the context of in vivo glycemic traits from the same patients.

Methods

Fasting blood was collected before surgery, and pancreatic tissue was frozen after resection from 18 patients undergoing pancreatectomy. Islet tissue was isolated by laser capture microdissection. Islet transcriptome was analyzed using microarray and quantitative RT-PCR. Proteins were examined by immunohistochemistry and western blotting. The association of gene variants with insulin secretion was investigated with oral glucose tolerance test (OGTT)-derived insulin secretion measured in a large cohort of subjects at increased risk of type 2 diabetes and with hyperglycemic clamp in a subset.

Results

Differential gene expression between islets from normoglycemic and hyperglycemic patients was prominent for the glycolytic enzyme ALDOB and the obesity-associated gene FAIM2. The mRNA levels of both genes correlated negatively with insulin secretion and positively with HbA1c. Islets of hyperglycemic patients displayed increased ALDOB immunoreactivity in insulin-positive cells, whereas α- and δ-cells were negative. Exposure of isolated islets to hyperglycemia augmented ALDOB expression. The minor allele of the ALDOB variant rs550915 associated with significantly higher levels of C-peptide and insulin during OGTT and hyperglycemic clamp, respectively.

Conclusion

Our analyses suggest that increased ALDOB expression in human islets is associated with lower insulin secretion.
Role of Endocannabinoid System in the Peripheral Antinociceptive Action of Aripiprazole
Authors: Ferreira Renata C. M. , Almeida-Santos Ana F. , Duarte Igor D. G. , Aguiar Daniele C. , Moreira Fabricio A. , Romero Thiago R. L.
Published: September 2018

BACKGROUND:

Recently, we demonstrated that the antipsychotic dopaminergic and serotoninergic agonist aripiprazole induced peripheral antinociception. However, the mechanism underlying this effect has not been fully established. Here, our aim was to identify possible relationships between this action of aripiprazole and the endocannabinoid system.

METHODS:

All drugs were given locally into the right hind paw of male Swiss mice weighing 30–35 g in a volume of 20 µL. The hyperalgesia was induced by intraplantar injection of prostaglandin E2 (2 μg). Aripiprazole was injected 10 minutes before the measurement, and an irreversible inhibitor of anandamide hydrolase (MAFP), an inhibitor for monoacylglycerol lipase (JZL184), and an anandamide reuptake inhibitor (VDM11) were given 10 minutes before the aripiprazole. Nociceptive thresholds were measured using an algesimetric apparatus in the third hour after prostaglandin E2 injection. Data were analyzed by ANOVA and Bonferroni tests.

RESULTS:

The antinociceptive effect induced by aripiprazole (100 μg) was blocked by cannabinoid 1 or 2 receptor antagonists AM251 (40 μg [P < .01], 80 μg [P < .0001], and 160 μg [P < .0001]) and AM630 (100 μg [P < .0001], 200 μg [P < .0001], and 400 μg [P < .0001]), respectively. The peripheral antinociception induced by aripiprazole (25 μg) was enhanced by administration of the inhibitor of fatty acid amide hydrolase (MAFP, 0.5 μg [P < .0001]) or monoacylglycerol lipase (JZL184, 4 μg [P < .0001]). Moreover, a similar enhancement was observed with the anandamide reuptake inhibitor (VDM11, 2.5 μg [P < .0001]).

CONCLUSIONS:

These results provide evidence for the involvement of the endocannabinoid system in peripheral antinociception induced by aripiprazole treatment.
Evaluation of the Determinants of Satisfaction With Postoperative Pain Control After Thoracoscopic Surgery: A Single-Center, Survey-Based Study
Authors: Siu Emily , Quick John S. , Xu Xinling , Correll Darin J.
Published: September 2018

BACKGROUND:

The need to measure, compare, and improve the quality of pain management is important to patients, payers, and health care providers. Pain after thoracic surgery can be severe, and thoracoscopic approaches have not had the favorable impact on pain as anticipated. The aim of this study was to evaluate the determinants of patient satisfaction with acute pain management and the effectiveness of pain control after video-assisted thoracoscopic surgery using a modified version of the Revised American Pain Society Patient Outcome Questionnaire.

METHODS:

We performed a single-center, prospective, survey-based study of 300 patients who had undergone elective video-assisted thoracoscopic surgery. Patients were enrolled and completed the survey on postoperative day 1 or 2. The primary outcome variable was patient-reported satisfaction with acute postoperative pain treatment measured on a 1–4 scale. The relationship between the items on the survey and patient satisfaction was analyzed to determine the factors significantly associated with satisfaction.

RESULTS:

Fifty-one percent of the patients had the highest satisfaction level with pain treatment, and 4% of the patients had the lowest satisfaction level. The mean reported acceptable pain level was 3.8 ± 1.9 (numeric rating scale [NRS], 0–10). The average pain intensity score at the time of the survey was 2.8 ± 2.1 (NRS, 0–10). The median for the most pain in the prior 24 hours was 7 (NRS, 0–10; interquartile range, 5–9). Five items from the survey were significantly associated with the satisfaction level. The predictor with the highest associated odds ratio (OR) with satisfaction was the ability to participate in pain management decisions (OR, 1.45; P < .0001). Another positively associated predictor was receiving helpful information about pain treatment options (OR, 1.31; P = .002). Negatively associated predictors of patient satisfaction included level of pain intensity at time of survey (OR, 0.76; P = .002), lowest pain score in the prior 24 hours (OR, 0.70; P = .0006), and having pain interfere with sleep in the postoperative period (OR, 0.72; P = .037).

CONCLUSIONS:

Our findings highlight several factors associated with patient satisfaction with acute postoperative pain management. Interventions focused on achieving acceptable pain levels for the majority of the time, ensuring that patients are able to get sleep, providing patients with helpful information about their pain treatment, and, most importantly, allowing patients to participate in decisions about their pain management may improve patient satisfaction with postoperative pain management.
Nighttime Extubation Does Not Increase Risk of Reintubation, Length of Stay, or Mortality: Experience of a Large, Urban, Teaching Hospital
Authors: Everhart Kelly K. , Khorsand Sarah , Khandelwal Nita , Michaelsen Kelly E. , Spiekerman Charles F. , Joffe Aaron M.
Published: September 2018

BACKGROUND:

In the intensive care unit (ICU), extubation failure has been associated with greater resource utilization and worsened clinical outcomes. Most recently, nighttime extubation (NTE) has been reported as a risk factor for increased ICU and hospital mortality. We hypothesized that, in a large, urban, university-affiliated hospital with multidisciplinary assessment for extubation, rigorously protocolized extubation algorithms, and expert airway managers available at all times of day for assessment of high-risk extubations, NTE would not confer additional risk of adverse clinical outcomes.

METHODS:

This was a retrospective cohort study of mechanically ventilated adults at a single university-affiliated hospital. NTE was defined as occurring between 7:00 pm and 6:59 am the following day. All data were extracted from the institution’s electronic medical record. Multivariable regression analyses were used to assess associations between NTE and reintubation, ICU and hospital length of stay (LOS), and mortality with adjustments for demographic and clinical covariates defined a priori. Palliative, unplanned, and routine postoperative extubations were excluded in sensitivity analyses.

RESULTS:

Of 2241 patients, 204 of 2241 (9.1%) underwent NTE. The rates of reintubation (NTE 6.9% versus daytime extubation [DTE] 12.4%; adjusted odds ratio [95% confidence interval {CI}], 0.78 [0.43–1.41]; P = .41) and in-hospital mortality (NTE 3.4% versus DTE 5.9%; adjusted odds ratio [95% CI], 0.72 [0.28–1.84]; P = .49) were not found to differ. NTE, compared to DTE, was associated with shorter duration of mechanical ventilation (median [interquartile range], 1 [0–1] days vs 2 [1–4] days; adjusted ratio of geometric means [RGMs] [95% CI], 0.64 [0.54–0.70]; P < .001), ICU (2 [1–5] days vs 4 [2–10] days; adjusted RGMs [95% CI], 0.65 [0.57–0.75]; P < .001), and hospital LOS (6 [3–18] days vs 13 [6–25] days; adjusted RGMs [95% CI], 0.64 [0.56–0.74]; P < .001). These results were unchanged in sensitivity analyses.

CONCLUSIONS:

Patients who underwent NTE were not at increased risk of reintubation or in-hospital mortality. In addition, NTE was associated with a shortened duration of mechanical ventilation and hospital LOS. In health care systems with similar critical care delivery models, NTE may coincide with reduced resource utilization in appropriately selected patients.
Radiation Safety Perceptions and Practices Among Pediatric Anesthesiologists: A Survey of the Physician Membership of the Society for Pediatric Anesthesia
Authors: Whitney Gina M. , Thomas James J. , Austin Thomas M. , Fanfan Jemel , Yaster Myron
Published: September 2018

BACKGROUND:

Pediatric anesthesiologists are exposed to ionizing radiation from x-rays on an almost daily basis. Our goal was to determine the culture of safety in which they work and how they adhere to preventative strategies that minimize exposure risk in their daily practice.

METHODS:

After Institutional Review Board waiver and approval of the Society for Pediatric Anesthesia’s research and quality and safety committees, an electronic e-mail questionnaire was sent to the Society’s physician, nontrainee members and consisted of questions specific to provider use of protective lead shielding, the routine use of dosimeters, and demographic information. Univariate analyses were performed using the Wilcoxon rank sum test for ordinal variables, the Fisher exact test for categorical variables, and the Spearman test to analyze correlation between 2 ordinal variables, while a proportional odds logistic regression was used for a multivariable ordinal outcome analysis. P values of <.05 were considered statistically significant.

RESULTS:

Twenty-one percent (674/3151) of the surveyed anesthesiologists completed the online questionnaire. Radiation exposure is ubiquitous (98.7%), and regardless of sex, most respondents were either concerned or very concerned about radiation exposure (76.8%); however, women were significantly more concerned than men (proportional odds ratio, 1.66 [95% confidence interval, 1.20–2.31]; P = .002). Despite this and independent of sex, level of concern was not associated with use of a radiation dosimeter (P = .85), lead glasses (odds ratio, 1.07 [95% confidence interval, 0.52–2.39]; P = 1.0), or a thyroid shield (P = .12). Dosimeters were rarely (13%) or never used (52%) and were mandated in only 28.5% of institutions. Virtually none of the respondents had ever taken a radiation safety course, received a personal radiation dose report, notification of their radiation exposure, or knew how many millirem/y was considered safe. Half of the respondents were female, and while pregnant, 73% (151/206) tried to avoid radiation exposure by requesting not to be assigned to cases requiring x-rays. These requests were honored 78% (160/206) of the time.

DISCUSSION:

Despite universal exposure to ionizing radiation from x-rays, pediatric anesthesiologists do not routinely adhere to strategies designed to limit the intensity of this exposure and rarely work in institutions in which a culture of radiation safety exists. Our study highlights the need to improve radiation safety education, the need to change the safety culture within the operating rooms and imaging suites, and the need to more fully investigate the utility of dosimeters, lead shielding, and eye safety measures in pediatric anesthesia practice.
Atmospheric Things
Authors: McCormack Derek P.
Published: September 2018

In Atmospheric Things Derek P. McCormack explores how atmospheres are imagined, understood, and experienced through experiments with a deceptively simple object: the balloon. Since the invention of balloon flight in the late eighteenth century, balloons have drawn crowds at fairs and expositions, inspired the visions of artists and writers, and driven technological development from meteorology to military surveillance. By foregrounding the distinctive properties of the balloon, McCormack reveals its remarkable capacity to disclose the affective and meteorological dimensions of atmospheres. Drawing together different senses of the object, the elements, and experience, McCormack uses the balloon to show how practices and technologies of envelopment allow atmospheres to be generated, made meaningful, and modified. He traces the alluring entanglement of envelopment in artistic, political, and technological projects, from the 2009 Pixar movie Up and Andy Warhol’s 1966 installation Silver Clouds to the use of propaganda balloons during the Cold War and Google's experiments with delivering internet access with stratospheric balloons. In so doing, McCormack offers new ways to conceive of, sense, and value the atmospheres in which life is immersed.
piRNAs and PIWI proteins: regulators of gene expression in development and stem cells
Authors: Rojas-Ríos Patricia , Simonelig Martine
Published: September 2018

PIWI proteins and Piwi-interacting RNAs (piRNAs) have established and conserved roles in repressing transposable elements (TEs) in the germline of animals. However, in several biological contexts, a large proportion of piRNAs are not related to TE sequences and, accordingly, functions for piRNAs and PIWI proteins that are independent of TE regulation have been identified. This aspect of piRNA biology is expanding rapidly. Indeed, recent reports have revealed the role of piRNAs in the regulation of endogenous gene expression programs in germ cells, as well as in somatic tissues, challenging dogma in the piRNA field. In this Review, we focus on recent data addressing the biological and developmental functions of piRNAs, highlighting their roles in embryonic patterning, germ cell specification, stem cell biology, neuronal activity and metabolism.
Aquatic versus terrestrial crab skeletal support: morphology, mechanics, molting and scaling
Authors: Taylor Jennifer R. A.
Published: September 2018

The transition from aquatic to terrestrial environments places significant mechanical challenges on skeletal support systems. Crabs have made this transition multiple times and are the largest arthropods to inhabit both environments. Furthermore, they alternate between rigid and hydrostatic skeletons, making them an interesting system to examine mechanical adaptations in skeletal support systems. I hypothesized that terrestrial crabs have modified morphology to enhance mechanical stiffness and that rigid and hydrostatic skeletons scale differently from each other, with stronger allometric relationships on land. Using the aquatic blue crab, Callinectes sapidus, and the terrestrial blackback land crab, Gecarcinus lateralis, I measured and compared body mass, merus morphology (dimensions, cuticle thickness, and I) and mechanics (EI, E, critical stress, and hydrostatic pressure) of rigid and hydrostatic stage crabs encompassing a range of sizes (C. sapidus: 1.5-133 g, N≤24; G. lateralis: 22-70 g, N≤15). Results revealed that rigid G. lateralis has similar morphology (L/D and T/D) than C. sapidus, but the mechanics and most scaling relationships are the same. Hydrostatic land crabs differ from aquatic crabs by having different morphology (thinner cuticle), mechanics (greater internal pressures), and scaling relationship (cuticle thickness). These results suggest that the rigid crab body plan is inherently overbuilt and sufficient to deal with the greater gravitational loading that occurs on land, while mechanical adaptations are important for hydrostatically supported crabs. Compared to other arthropods and hydrostatic animals, crabs possess distinct strategies for adapting mechanically to life on land.
Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats (Capra aegagrus hircus)
Authors: Ackermans Nicole L. , Winkler Daniela E. , Schulz-Kornas Ellen , Kaiser Thomas M. , Müller Dennis W. H. , Kircher Patrick R. , Hummel Jürgen , Clauss Marcus , Hatt Jean-Michel
Published: September 2018

Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical for grazers and high, sharp cusps typical for browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, grass and rice husks, grass, rice husks and sand) were fed to four groups of a total of 28 adult goats in a controlled feeding experiment over a six-month period. Tooth morphology was captured by medical CT scans at the beginning and end of the experiment. These scans, as well as the crania obtained postmortem, were scored using the mesowear method. Comparisons between diet groups only showed few significant differences after six months, irrespective of whether CT scans or the real teeth were scored. Only when assessing the difference in signal between start and end did relevant, significant diet-specific effects emerge. Diets containing lower phytolith content caused a more pronounced change in mesowear towards sharper cusps/higher reliefs, while the feed containing sand did not result in more extreme changes in mesowear when compared to the same feed without sand. Our experiment suggests that the formation of a stable and hence reliable mesowear signal requires more time to develop than six months.
Experimental Research on Labor Market Discrimination
Authors: Neumark David
Published: September 2018

Understanding whether labor market discrimination explains inferior labor market outcomes for many groups has drawn the attention of labor economists for decades— at least since the publication of Gary Becker’s The Economics of Discrimination in 1957. The decades of research on discrimination in labor markets began with a regression-based “decomposition” approach, asking whether raw wage or earnings differences between groups—which might constitute prima facie evidence of discrimination—were in fact attributable to other productivity-related factors. Subsequent research—responding in large part to limitations of the regression-based approach—moved on to other approaches, such as using firm-level data to estimate both marginal productivity and wage differentials. In recent years, however, there has been substantial growth in experimental research on labor market discrimination—although the earliest experiments were done decades ago. Some experimental research on labor market discrimination takes place in the lab. But far more of it is done in the field, which makes this particular area of experimental research unique relative to the explosion of experimental economic research more generally. This paper surveys the full range of experimental literature on labor market discrimination, places it in the context of the broader research literature on labor market discrimination, discusses the experimental literature from many different perspectives (empirical, theoretical, and policy), and reviews both what this literature has taught us thus far, and what remains to be done. (JEL C93, J14, J15, J16, J23, J41, J71)
Reduced-dose computed tomography to detect dorsal screw protrusion after distal radius volar plating
Authors: Leffers Kevin J. , Kosty John W. , Garcia Glenn M. , Jupiter Daniel C , Lindsey Ronald W. , Gugala Zbigniew
Published: September 2018

Background: Tenosynovitis and tendon rupture caused by screw penetration of the dorsal cortex are common complications after fixed-angle volar plating of a distal radius fracture. Detecting screw prominence with plain radiography is difficult due to the topography of the distal radius dorsal cortex. Computed tomography (CT) offers more detailed imaging of the bone topography, but is associated with radiation exposure. The present cadaveric study compared reduced-dose and standard-dose CT protocols in the detection of dorsal screw protrusion after fixed-angle volar plating of distal radius fracture. If found equivalent, a reduced-dose protocol could decrease the total radiation exposure to patients.

Methods: Standard size distal radius volar locking plates were placed using a standard Henry approach in 3 matched pairs of cadaver wrists. A total of 3 distal locking screws were placed at 3 different lengths for a total of 3 rounds of CT scans per wrist pair. Each wrist pair was imaged by CT using standard-dose and reduced-dose protocols. Dorsal screw penetration was measured in each imaging protocol by 3 radiologists at two time periods to calculate inter- and intra-observer variability. Variability was calculated using the concordance correlation coefficient (CCC), intra-class correlation coefficient (ICC), and Pearson correlation coefficient (PCC). Bland-Altman plots were used and assessed 95% limits of agreement.

Results: Intra- and inter-observer variabilities, either with the reduced-dose or standard-dose protocol, were >0.85. Pairwise CCC, ICC, and PCC were >0.91. In the comparison of reduced dose versus standard dose between radiologists, correlations were always >0.95.

Conclusions: Comparison of a reduced-dose CT protocol and a standard-dose CT protocol for the detection of dorsal penetrating screws after fixed-angle volar plating showed >0.95 correlation in this cadaveric model. A reduced-dose CT protocol is equivalent to a standard dose CT protocol for orthopedic imaging and should reduce radiation exposure.
methyvim: Targeted, robust, and model-free differential methylation analysis in R
Authors: Hejazi Nima S. , Phillips Rachael V. , Hubbard Alan E. , van der Laan Mark J.
Published: September 2018

We present methyvim, an R package implementing an algorithm for the nonparametric estimation of the effects of exposures on DNA methylation at CpG sites throughout the genome, complete with straightforward statistical inference for such estimates. The approach leverages variable importance measures derived from statistical parameters arising in causal inference, defined in such a manner that they may be used to obtain targeted estimates of the relative importance of individual CpG sites with respect to a binary treatment assigned at the phenotype level, thereby providing a new approach to identifying differentially methylated positions. The procedure implemented is computationally efficient, incorporating a preliminary screening step to isolate a subset of sites for which there is cursory evidence of differential methylation as well as a unique multiple testing correction to control the False Discovery Rate with the same rigor as would be available if all sites were subjected to testing. This novel technique for analysis of differentially methylated positions provides an avenue for incorporating flexible state-of-the-art data-adaptive regression procedures (i.e., machine learning) into the estimation of differential methylation effects without the loss of interpretable statistical inference for the estimated quantity.