806 research outputs found
Evaluation of the Workplace Environment in the UK, and the Impact on Users’ Levels of Stimulation
The purpose of this study is to evaluate a number of recently completed workplaces in the UK. The first aim is to assess the impact of various aspects of the workplace environment on users’ levels of stimulation. The body of previous research undertaken into the workplace environment, identified the aspects to be investigated. Samples of employees from the sixteen businesses were surveyed to determine their perceptions of the workplaces. The results were entered into a regression analysis, and the most significant predictors of perceived stimulation identified. The data also revealed a dramatic reduction in staff arousal levels from mornings to afternoons. Thus, there is a second aim to determine whether changes to significant aspects of the workplace environment during the day can counteract the reduction in users’ stimulation. Two further workplaces were studied to enable changes to be made over a 12-week period. A sample of employees completed questionnaires, and semi-structured interviews revealed the reasons behind the results. It was found that provision of artwork, personal control of temperature and ventilation and regular breaks were the most significant contributions to increasing stimulation after lunch; while user choice of layout, and design and décor of workspaces and break areas, were the most significant aspects at design stage
Metabolic and nutritional support of critically ill patients: consensus and controversies.
The results of recent large-scale clinical trials have led us to review our understanding of the metabolic response to stress and the most appropriate means of managing nutrition in critically ill patients. This review presents an update in this field, identifying and discussing a number of areas for which consensus has been reached and others where controversy remains and presenting areas for future research. We discuss optimal calorie and protein intake, the incidence and management of re-feeding syndrome, the role of gastric residual volume monitoring, the place of supplemental parenteral nutrition when enteral feeding is deemed insufficient, the role of indirect calorimetry, and potential indications for several pharmaconutrients
Algorithm and performance of a clinical IMRT beam-angle optimization system
This paper describes the algorithm and examines the performance of an IMRT
beam-angle optimization (BAO) system. In this algorithm successive sets of beam
angles are selected from a set of predefined directions using a fast simulated
annealing (FSA) algorithm. An IMRT beam-profile optimization is performed on
each generated set of beams. The IMRT optimization is accelerated by using a
fast dose calculation method that utilizes a precomputed dose kernel. A compact
kernel is constructed for each of the predefined beams prior to starting the
FSA algorithm. The IMRT optimizations during the BAO are then performed using
these kernels in a fast dose calculation engine. This technique allows the IMRT
optimization to be performed more than two orders of magnitude faster than a
similar optimization that uses a convolution dose calculation engine.Comment: Final version that appeared in Phys. Med. Biol. 48 (2003) 3191-3212.
Original EPS figures have been converted to PNG files due to size limi
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Bright spots: seeds of a good Anthropocene
The scale, rate, and intensity of humans’ environmental impact has engendered broad discussion about how to find plausible pathways of development that hold the most promise for fostering a better future in the Anthropocene. However, the dominance of dystopian visions of irreversible environmental degradation and societal collapse, along with overly optimistic utopias and business‐as‐usual scenarios that lack insight and innovation, frustrate progress. Here, we present a novel approach to thinking about the future that builds on experiences drawn from a diversity of practices, worldviews, values, and regions that could accelerate the adoption of pathways to transformative change (change that goes beyond incremental improvements). Using an analysis of 100 initiatives, or “seeds of a good Anthropocene”, we find that emphasizing hopeful elements of existing practice offers the opportunity to: (1) understand the values and features that constitute a good Anthropocene, (2) determine the processes that lead to the emergence and growth of initiatives that fundamentally change human–environmental relationships, and (3) generate creative, bottom‐up scenarios that feature well‐articulated pathways toward a more positive future
Omega-3 supplementation in patients with sepsis: a systematic review and meta-analysis of randomized trials.
BACKGROUND: Nutritional supplementation of omega-3 fatty acids has been proposed to modulate the balance of pro- and anti-inflammatory mediators in sepsis. If proved to improve clinical outcomes in critically ill patients with sepsis, this intervention would be easy to implement. However, the cumulative evidence from several randomized clinical trials (RCTs) remains unclear. METHODS: We searched the Cochrane Library, MEDLINE, and EMBASE through December 2016 for RCTs on parenteral or enteral omega-3 supplementation in adult critically ill patients diagnosed with sepsis or septic shock. We analysed the included studies for mortality, intensive care unit (ICU) length of stay, and duration of mechanical ventilation, and used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the quality of the evidence for each outcome. RESULTS: A total of 17 RCTs enrolling 1239 patients met our inclusion criteria. Omega-3 supplementation compared to no supplementation or placebo had no significant effect on mortality [relative risk (RR) 0.85; 95% confidence interval (CI) 0.71, 1.03; P = 0.10; I (2) = 0%; moderate quality], but significantly reduced ICU length of stay [mean difference (MD) -3.79 days; 95% CI -5.49, -2.09; P < 0.0001, I (2) = 82%; very low quality] and duration of mechanical ventilation (MD -2.27 days; 95% CI -4.27, -0.27; P = 0.03, I (2) = 60%; very low quality). However, sensitivity analyses challenged the robustness of these results. CONCLUSION: Omega-3 nutritional supplementation may reduce ICU length of stay and duration of mechanical ventilation without significantly affecting mortality, but the very low quality of overall evidence is insufficient to justify the routine use of omega-3 fatty acids in the management of sepsis
A multidimensional platform for the purification of non-coding RNA species
A renewed interest in non-coding RNA (ncRNA) has led to the discovery of novel RNA species and post-transcriptional ribonucleoside modifications, and an emerging appreciation for the role of ncRNA in RNA epigenetics. Although much can be learned by amplification-based analysis of ncRNA sequence and quantity, there is a significant need for direct analysis of RNA, which has led to numerous methods for purification of specific ncRNA molecules. However, no single method allows purification of the full range of cellular ncRNA species. To this end, we developed a multidimensional chromatographic platform to resolve, isolate and quantify all canonical ncRNAs in a single sample of cells or tissue, as well as novel ncRNA species. The applicability of the platform is demonstrated in analyses of ncRNA from bacteria, human cells and plasmodium-infected reticulocytes, as well as a viral RNA genome. Among the many potential applications of this platform are a system-level analysis of the dozens of modified ribonucleosides in ncRNA, characterization of novel long ncRNA species, enhanced detection of rare transcript variants and analysis of viral genomes.Singapore-MIT Alliance for Research and TechnologyNational Institute of Environmental Health Sciences (ES017010)National Institute of Environmental Health Sciences (ES002109
Early enteral nutrition in critically ill patients: ESICM clinical practice guidelines.
To provide evidence-based guidelines for early enteral nutrition (EEN) during critical illness.
We aimed to compare EEN vs. early parenteral nutrition (PN) and vs. delayed EN. We defined "early" EN as EN started within 48 h independent of type or amount. We listed, a priori, conditions in which EN is often delayed, and performed systematic reviews in 24 such subtopics. If sufficient evidence was available, we performed meta-analyses; if not, we qualitatively summarized the evidence and based our recommendations on expert opinion. We used the GRADE approach for guideline development. The final recommendations were compiled via Delphi rounds.
We formulated 17 recommendations favouring initiation of EEN and seven recommendations favouring delaying EN. We performed five meta-analyses: in unselected critically ill patients, and specifically in traumatic brain injury, severe acute pancreatitis, gastrointestinal (GI) surgery and abdominal trauma. EEN reduced infectious complications in unselected critically ill patients, in patients with severe acute pancreatitis, and after GI surgery. We did not detect any evidence of superiority for early PN or delayed EN over EEN. All recommendations are weak because of the low quality of evidence, with several based only on expert opinion.
We suggest using EEN in the majority of critically ill under certain precautions. In the absence of evidence, we suggest delaying EN in critically ill patients with uncontrolled shock, uncontrolled hypoxaemia and acidosis, uncontrolled upper GI bleeding, gastric aspirate >500 ml/6 h, bowel ischaemia, bowel obstruction, abdominal compartment syndrome, and high-output fistula without distal feeding access
Goal-directed Intraoperative therapy reduces morbidity and length of hospital stay in high-risk surgical patients
Abstract: Background: Postoperative organ failures commonly occur after major abdominal surgery, increasing the utilization of resources and costs of care. Tissue hypoxia is a key trigger of organ dysfunction. A therapeutic strategy designed to detect and reverse tissue hypoxia, as diagnosed by an increase of oxygen extraction (0,ER) over a predefined threshold, could decrease the incidence of organ failures. The primary aim of this study was to compare the number of patients with postoperative organ failure and length of hospital stay between those randomized to conventional vs a protocolized strategy designed to maintain O2ER < 27%.
Methods: A prospective, randomized, controlled trial was performed in nine hospitals in Italy. One hundred thirty-five high-risk patients scheduled for major abdominal surgery were randomized in two groups. All patients were managed to achieve standard goals: mean arterial pressure > 80 mm Hg and urinary output > 0.5 mL/kg/h. The patients of the "pr..
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