Cluster secondary ion mass spectrometry (cluster SIMS) has played a critical role in the characterization of polymeric materials over the last decade, allowing for the ability to obtain spatially ...resolved surface and in-depth molecular information from many polymer systems. With the advent of new molecular sources such as ${\rm C}_{60}^ +$, ${\rm Au}_3^ +$, ${\rm SF}_5^ +$, and ${\rm Bi}_3^ +$, there are considerable increases in secondary ion signal as compared to more conventional atomic beams (Ar⁺, Cs⁺, or Ga⁺). In addition, compositional depth profiling in organic and polymeric systems is now feasible, without the rapid signal decay that is typically observed under atomic bombardment. The premise behind the success of cluster SIMS is that compared to atomic beams, polyatomic beams tend to cause surface-localized damage with rapid sputter removal rates, resulting in a system at equilibrium, where the damage created is rapidly removed before it can accumulate. Though this may be partly true, there are actually much more complex chemistries occurring under polyatomic bombardment of organic and polymeric materials, which need to be considered and discussed to better understand and define the important parameters for successful depth profiling. The following presents a review of the current literature on polymer analysis using cluster beams. This review will focus on the surface and in-depth characterization of polymer samples with cluster sources, but will also discuss the characterization of other relevant organic materials, and basic polymer radiation chemistry.
This book presents the first large-scale study of lobbying strategies and outcomes in the United States and the European Union, two of the most powerful political systems in the world. Every day, ...tens of thousands of lobbyists in Washington and Brussels are working to protect and promote their interests in the policymaking process. Policies emanating from these two spheres have global impacts-they set global standards, they influence global markets, and they determine global politics. Armed with extensive new data, Christine Mahoney challenges the conventional stereotypes that attribute any differences between the two systems to cultural ones-the American, a partisan and combative approach, and the European, a consensus-based one. Mahoney draws from 149 interviews involving 47 issues to detail how institutional structures, the nature of specific issues, and characteristics of the interest groups combine to determine decisions about how to approach a political fight, what arguments to use, and how to frame an issue. She looks at how lobbyists choose lobbying tactics, public relations strategies, and networking and coalition activities. Her analysis demonstrates that advocacy can be better understood when we study the lobbying of interest groups in their institutional and issue context. This book offers new insights into how the process of lobbying works on both sides of the Atlantic.
This longitudinal study among Registered Nurses has four purposes: (1) to investigate whether emotional, quantitative and physical demands, and family-work conflict have a negative impact on nurses' ...perceived effort; (2) to investigate whether quality of leadership, developmental opportunities, and social support from supervisors and colleagues have a positive impact on meaning of work; (3) to investigate whether burnout from the combined impact of perceived effort and meaning of work mediates the relationship with occupational turnover intention; and (4) whether the relationships in our overall hypothesized framework are moderated by age (nurses categorized under 40 years versus ≥ 40 years old). In line with our expectations, emotional, quantitative, and physical demands, plus family-work conflict appeared to increase levels of perceived effort. Quality of leadership, developmental opportunities, and social support from supervisors and colleagues increased the meaning of work levels. In addition, increased perceived stress resulted in higher burnout levels, while increased meaning of work resulted in decreased burnout levels. Finally, higher burnout levels appeared to lead to a higher occupational turnover intention. Obviously, a nursing workforce that is in good physical and psychological condition is only conceivable when health care managers protect the employability of their nursing staff, and when there is a dual responsibility for a sustainable workforce. Additionally, thorough attention for the character of job demands and job resources according to nurses' age category is necessary in creating meaningful management interventions.
Background
The objective of this study was to assess whether the use of staple line reinforcement (SLR) reduces staple line complications (SLC). Mechanical staple lines are essential for ...gastrointestinal surgery such as bariatric surgery. However, SLC, such as bleeding and leakage, still occur. The purposes of this study were to provide quantitative evidence on the relative efficacy of gastric SLR and to compare the rates of effectiveness of three commonly used methods.
Methods
A search of the medical literature in English language journals identified studies from Jan 1, 2000, to Dec 31, 2013, using the following reinforcement types: (1) no reinforcement, (2) oversewing, (3) a biocompatible glycolide copolymer, and (4) bovine pericardium after gastric bypasses and sleeve gastrectomies. Types of reinforcement were compared using a random-effects model.
Results
This meta-analysis reviewed 16,967 articles, extracting data on 56,309 patients concerning leak and 41,864 patients concerning bleeding. Over 40 % of patients had no reinforcement, resulting in the highest leak rate (2.75 %) and bleed rate (3.45 %). Overall, reinforcing with bovine pericardium had the lowest leak (1.28 %) and bleed (1.23 %) rates. Suture oversewing was better than no reinforcement but not as effective as bovine pericardium for leak (2.45 %) and bleed (2.69 %) rates. Buttressing with a biocompatible glycolide copolymer resulted in the second highest leak rate (2.61 %) and a bleed rate of 2.48 % but had significantly lower bleed rates than no reinforcement.
Conclusions
SLR provided superior results for patients compared to no reinforcement for reducing SLC. Buttressing with bovine pericardium resulted in the most favorable outcomes. The effectiveness of different methods used to reinforce the staple line in gastric surgery does not appear to be equal.
Scholars have avoided studying interest group influence because of the difficulty operationalising the concept. The research presented here introduces a new way of measuring lobbying success and lays ...out a model of its determinants. To understand why interest groups sometimes succeed and at other times fail, we must consider the institutional structure of the political system within which the advocates are operating; the characteristics of the issue at hand; and finally the characteristics of the interest group itself and their lobbying strategy. I test these factors with original data based on interviews with 149 advocates in Washington D.C. and Brussels active on a random sample of 47 policy issues. From the results, issue context emerges as a much more important determinant of lobbying success than institutional differences. The institutional differences that do emerge suggest that direct elections coupled with private campaign finance lead to winner-take-all outcomes biased in favour of wealthier business interests, while the lack of these institutional characteristics leads to more balanced policy compromises with more advocates achieving some of their policy goals.
Chronic low back pain is one of the most common causes of disability, affecting more than 600 million people worldwide with major social and economic costs. Current treatment options include ...conservative, surgical, and minimally invasive interventional treatment approaches. Novel therapeutic treatment options continue to develop, targeting the biological cascades involved in the degenerative processes to prevent invasive spinal surgical procedures. Both intradiscal platelet-rich plasma (PRP) and bone marrow concentrate (BMC) applications have been introduced as promising regenerative treatment procedures.
The primary objective of this study is to assess the safety and effectiveness of an orthobiologic intradiscal injection, PRP or BMC, when compared to control patients. The secondary objectives are to measure: patient satisfaction and incidence of hospitalization, emergency room visit and spine surgery at predetermined follow-up intervals.
A multicenter, prospective, crossover, randomized, controlled trial.
Comprehensive Spine and Sports Center and participating centers.
Forty patients were randomized into saline trigger point injection, intradiscal PRP, or BMC. Follow-up was 1, 3, 6, and 12 months posttreatment. Placebo patients were randomized to PRP and BMC injection if < 50% decrease in numeric rating scale (NRS) scores in 3 months, while PRP and BMC patients to the other active group if < 50% decrease in NRS scores in 6 months.
Both PRP and BMC demonstrated statistically significant improvement in pain and function. All the placebo patients reported < 50% pain relief and crossed to the active arm. None of the patients had any adverse effects, hospitalization, or surgery up to 12 months posttreatment.
The limitations of our study were the small number of patients and open-label nature of the study.
This is the only human lumbar disc study that evaluates both PRP and BMC in the same study and compares it to placebo. PRP and BMC were found to be superior to placebo in improving pain and function; however, larger randomized clinical trials are needed to answer further questions on the comparative effectiveness of various biologics as well as to identify outcome differences specific to disc pathology.
This book describes the importance of the emerging technique Cluster Secondary Ion Mass Spectrometry (SIMS), which is used for the analysis of a range of solid materials, including everything from ...organic and polymeric materials, to cells and semiconductors. The text covers a wide range of topics, encompassing fundamentals, theory, and applications including cluster sources, organic and polymeric depth profiling, and 3-D imaging in organic and polymeric materials. Written by founders in the field, this guide creates a peerless compendium of knowledge on this cutting edge set of methods.
Chemical images of the surfaces and the interiors of coatings of rapamycin in poly(lactic-co-glycolic acid) (PLGA) obtained by mass spectrometry and light scattering methods reveal a three ...dimensional picture of the chemical morphology of drug eluting coatings before, during, and after drug elution. The coating formulations examined ranged from 5 to 50 wt.% rapamycin in PLGA with and without a top layer (“capcoat”) of PLGA. Surface sensitive electron spectroscopy for chemical analysis (ESCA) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) indicated that the outer surface of the coatings (without a PLGA capcoat) were drug-rich prior to elution. TOF-SIMS depth profiling using SF
5
+ polyatomic primary ions revealed a drug-enriched region at the near surface of the non-capcoated coatings ranging in thickness from 5 to 115 nm. The chemical morphology of the rapamycin/PLGA coatings on stents was determined using scanning confocal Raman microscopy, from the surface through the bulk of the coatings. Images of the coatings on stents showed a homogeneous distribution of rapamycin for the coatings with low concentrations of drug (5 wt.%) and more non-uniform distributions for higher concentrations of rapamycin (>
25 wt.%). Images acquired from the interior of the films during the elution process indicated that rapamycin diffuses out of the coating but also segregates into drug-rich domains with increasing elution time. Optical interferometry measurements of coating thickness suggested that PLGA eroded from the coating during the elution experiment.
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