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Controlling the mechanical behavior of novel supramolecular materials is of the utmost importance and requires a fundamental understanding of the underlying physical processes. We present a multimethods approach to the dynamics of entangled transient polyisoprene networks. Small-angle neutron scattering (SANS) on randomly functionalized chains shows homogeneous supramolecular melts with Gaussian chain conformations. The H-bond lifetimes (dielectric α*-process) and the rheological response in terms of the loss modulus G″ differ by 2 orders of magnitude in time. Within the concept of a compact random walk (RW), where the random walker (urazole group acting as a sticker) undergoes multiple returns to its starting point and following the concept of theoretical proposed renormalized sticky bond lifetimes, we quantitatively solve this longstanding and unexplained large discrepancy: While the bond opening gives rise to the dielectric response, for rheological relaxation the association with a new partner is rele...

The outbreak of the coronavirus disease 2019 (COVID-19) and its rapid global spread have created unprecedented challenges to health care systems. Significant and sustained efforts have focused on mobilization of personal protective equipment, intensive care beds, and medical equipment, while substantially less attention has focused on preserving the psychological health of the medical workforce tasked with addressing the challenges of the pandemic. And yet, similar to battlefield conditions, health care workers are being confronted with ongoing uncertainty about resources, capacities, and risks; as well as exposure to suffering, death, and threats to their own safety. These conditions are engendering high levels of fear and anxiety in the short term, and place individuals at risk for persistent stress exposure syndromes, subclinical mental health symptoms, and professional burnout in the long term. Given the potentially wide-ranging mental health impact of COVID-19, protecting health care workers from adverse psychological effects of the pandemic is critical. Therefore, we present an overview of the potential psychological stress responses to the COVID-19 crisis in medical providers and describe preemptive resilience-promoting strategies at the organizational and personal level. We then describe a rapidly deployable Psychological Resilience Intervention founded on a peer support model (Battle Buddies) developed by the United States Army. This intervention-the product of a multidisciplinary collaboration between the Departments of Anesthesiology and Psychiatry & Behavioral Sciences at the University of Minnesota Medical Center-also incorporates evidence-informed "stress inoculation" methods developed for managing psychological stress exposure in providers deployed to disasters. Our multilevel, resource-efficient, and scalable approach places 2 key tools directly in the hands of providers: (1) a peer support Battle Buddy; and (2) a designated mental health consultant who can facilitate training in stress inoculation methods, provide additional support, or coordinate referral for external professional consultation. In parallel, we have instituted a voluntary research data-collection component that will enable us to evaluate the intervention's effectiveness while also identifying the most salient resilience factors for future iterations. It is our hope that these elements will provide guidance to other organizations seeking to protect the well-being of their medical workforce during the pandemic. Given the remarkable adaptability of human beings, we believe that, by promoting resilience, our diverse health care workforce can emerge from this monumental challenge with new skills, closer relationships, and greater confidence in the power of community.

The anesthesia market continues to undergo disruption. Financial margins are shrinking, and buyers are demanding that anesthesia services be provided in an efficient, low-cost manner. To help anesthesiologists analyze their market, Drucker and Porter's framework of buyers, suppliers, quality, barriers to entry, substitution, and strategic priorities allows for a structured analysis. Once this analysis is completed, anesthesiologists must articulate their value to other medical professionals and to hospitals. Anesthesiologists can survive and thrive in a value-based health care environment if they are capable of providing services differently and able to deliver cost-effective care.

International audience; A future circular collider (FCC) with a center-of-mass energy of 100 TeV and a circumference of around 100 km, or an energy upgrade of the LHC (HE-LHC) to 27 TeV require bending magnets providing 16 T in a 50-mm aperture. Several development programs for these magnets, based on Nb$_3$Sn technology, are being pursued in Europe and in the U.S. In these programs, cos-theta, block-type, common-coil, and canted-cos-theta magnets are explored; first model magnets are under manufacture; limits on conductor stress levels are studied; and a conductor with enhanced characteristics is developed. This paper summarizes and discusses the status, plans, and preliminary results of these programs.

While quality improvement (QI) initiatives can be a highly effective means for improving health care delivery in academic medical centers (AMCs), many health care professionals are not formally trained in basic QI methodology, engaging clinicians in QI activities can be challenging, and there is often a lack of integration and coordination among QI functions (eg, Departments of Quality and Safety, Continuing Professional Development). In our AMC, we undertook a collaborative approach to achieve better vertical and horizontal integration of our QI education efforts. This article provides a case example describing our organizational context, what was done, and with what effect and makes our example and lessons learned available to others.We developed a new educational QI program that was jointly planned and implemented by a group comprising major QI stakeholders. This project was intended to create horizontal organizational linkages between continuing professional development, clinicians, the hospital, and QI department and produce QI activities that aligned with the strategic objectives of senior management.The group developed and implemented a curriculum based on Lean methodology and concepts from the Institute for Health Care Improvement Model for Improvement. Two cohorts (27 teams) completed the training and planned and implemented QI projects. All projects were aligned with organizational quality, safety, and patient experience goals. The majority of projects met their aim statements.This case description provides an example of successful horizontal integration of an AMCs' QI functions to disseminate knowledge and implement meaningful QI aligned with strategic objectives (vertical integration).

A new dual network elastomer is developed that consists of polybutadiene crosslinked with both permanent and transient bonds. The transient network is formed by the association of urazole groups that are randomly attached to the polymer backbone. Subsequent orthogonal covalent crosslinking through hydrosilylation in the melt state leads to a dual network with variable permanent and transient crosslinking density. Small angle neutron scattering (SANS) investigations show a homogeneous distribution of the transient bonds in both the functionalized polymers and the dual network products. The enhanced mechanical properties of the dual networks compared to conventional polybutadiene elastomers are characterized by stress–strain measurements. The increased toughness can be explained by a protective mechanism where the weaker supramolecular bonds act as sacrificial bonds that dissipate energy.

A key ingredient within theories focusing on the rheology of entangled polymers is the way how the topological constraints of an entangled chain are lifted by unconstrained segments, i.e., how the constraining tube is dilated. This important question has been addressed by directly measuring the tube diameter $d$ at the scale of the tube by neutron spin echo spectroscopy. The tube diameter $d$ and plateau modulus ${G}_{N}^{0}$ of highly entangled polyethylene oxide (PEO) chains of volume fraction $c$ that are diluted by low molecular PEO show a concentration dependence $d\ensuremath{\propto}{c}^{a/2}$ and ${G}_{N}^{0}\ensuremath{\propto}{c}^{1+a}$ with an exponent $a$ close to $4/3$. This result allows the clear discrimination between different theoretical models that predict $4/3$ or other values between 1 and 2 and provides an important ingredient to tube model theories.

Supramolecular groups in polymeric systems lead to responsive materials which are ideally suited for applications in dynamic environments. The key to their advanced properties such as shape-memory or self-healing is the reversibility of secondary interactions which can be triggered by external stimuli such as temperature, light, or pH-value. Controlling the (mechanical) behavior of such systems requires a precise understanding of intrinsic properties. We present a multimethod study of transient polyisoprene networks that were functionalized with different amounts of hydrogen bonding urazole groups. This work aims at understanding rich rheological features on the basis of their microscopic origin. First, the thermorheological simple behavior is validated experimentally. Subsequently, we characterize the underlying microscopic processes by broadband dielectric spectroscopy (α-process and α∗-process), differential scanning calorimetry (glass transition behavior), and Fourier-transform infrared spectroscopy (thermodynamics of group association/dissociation). Based on these results, the influence of the supramolecular groups on the rheological response is analyzed. The observed features such as the onset of elastomeric properties in the flow regime, a drastic increase in the chain relaxation time with an increasing amount of functional groups, and the occurrence of a second rheological relaxation process, which is the most prominent effect, are discussed and related to their physical origin.

© 2016 by The American Society for Biochemistry and Molecular Biology, Inc. Numerous affinity purification-mass spectrometry (APMS) and yeast two-hybrid screens have each defined thousands of pairwise protein-protein interactions (PPIs), most of which are between functionally unrelated proteins. The accuracy of these networks, however, is under debate. Here, we present an AP-MS survey of the bacterium Desulfovibrio vulgaris together with a critical reanalysis of nine published bacterial yeast two-hybrid and AP-MS screens. We have identified 459 high confidence PPIs from D. vulgaris and 391 from Escherichia coli. Compared with the nine published interactomes, our two networks are smaller, are much less highly connected, and have significantly lower false discovery rates. In addition, our interactomes are much more enriched in protein pairs that are encoded in the same operon, have similar functions, and are reproducibly detected in other physical interaction assays than the pairs reported in prior studies. Our work establishes more stringent benchmarks for the properties of protein interactomes and suggests that bona fide PPIs much more frequently involve protein partners that are annotated with similar functions or that can be validated in independent assays than earlier studies suggested.

The ability to conduct advanced functional genomic studies of the thousands of sequenced bacteria has been hampered by the lack of available tools for making high-throughput chromosomal manipulations in a systematic manner that can be applied across diverse species. In this work, we highlight the use of synthetic biological tools to assemble custom suicide vectors with reusable and interchangeable DNA “parts” to facilitate chromosomal modification at designated loci. These constructs enable an array of downstream applications, including gene replacement and the creation of gene fusions with affinity purification or localization tags. We employed this approach to engineer chromosomal modifications in a bacterium that has previously proven difficult to manipulate genetically, Desulfovibrio vulgaris Hildenborough, to generate a library of over 700 strains. Furthermore, we demonstrate how these modifications can be used for examining metabolic pathways, protein-protein interactions, and protein localization. The ubiquity of suicide constructs in gene replacement throughout biology suggests that this approach can be applied to engineer a broad range of species for a diverse array of systems biological applications and is amenable to high-throughput implementation.

Monothiol glutaredoxins (mono-Grx) represent a highly evolutionarily conserved class of proteins present in organisms ranging from prokaryotes to humans. Mono-Grxs have been implicated in iron sulfur (FeS) cluster biosynthesis as potential scaffold proteins and in iron homeostasis via an FeS-containing complex with Fra2p (homologue of E. coli BolA) in yeast and are linked to signal transduction in mammalian systems. However, the function of the mono-Grx in prokaryotes and the nature of an interaction with BolA-like proteins have not been established. Recent genome-wide screens for E. coli genetic interactions reported the synthetic lethality (combination of mutations leading to cell death; mutation of only one of these genes does not) of a grxD mutation when combined with strains defective in FeS cluster biosynthesis (isc operon) functions [Butland, G., et al. (2008) Nature Methods 5, 789-795]. These data connected the only E. coli mono-Grx, GrxD to a potential role in FeS cluster biosynthesis. We investigated GrxD to uncover the molecular basis of this synthetic lethality and observed that GrxD can form FeS-bound homodimeric and BolA containing heterodimeric complexes. These complexes display substantially different spectroscopic and functional properties, including the ability to act as scaffold proteins for intact FeS cluster transfer to the model [2Fe-2S] acceptor protein E. coli apo-ferredoxin (Fdx), with the homodimer being significantly more efficient. In this work, we functionally dissect the potential cellular roles of GrxD as a component of both homodimeric and heterodimeric complexes to ultimately uncover if either of these complexes performs functions linked to FeS cluster biosynthesis.

Background Electromagnetic interference (EMI) induced by electrocautery during surgery in patients with cardiac pacemakers or implanted cardioverter-defibrillators (ICDs) may inhibit pacing and cause inappropriate tachyarrhythmia oversensing. In particular, susceptibility to EMI may be enhanced in ICDs by frequently used wide interelectrode sensing (i.e., integrated bipolar sensing). Consequently, ICD function is usually disabled preoperatively and restored later by noninvasive programming. Because sensing by closely spaced electrodes (i.e., true bipolar) may be less susceptible to EMI, preoperative programming to a true bipolar mode may minimize the need for perioperative programming while preserving device function. Methods Our study population consisted of 23 consecutive patients either receiving a new ICD or undergoing ICD pulse generator change. In each patient, electrocautery-induced EMI was initiated with the ICD in the closely spaced sensing configuration and again during widely spaced sensing. Results In comparing the 2 sensing modes, right ventricular electrogram amplitude was significantly greater and EMI noise amplitude tended to be greater with widely spaced bipolar sensing. Furthermore, widely spaced bipolar sensing was associated with ICD pacing inhibition in 22 of 23 patients and incorrect "ventricular fibrillation" detection in 17 of 23 patients. Conversely, closely spaced bipolar sensing was not accompanied by either pacing inhibition or incorrect ventricular fibrillation sensing. Conclusion Closely spaced bipolar sensing (i.e., true bipolar) appropriately rejects electrocautery-induced EMI. Programming implanted devices to closely spaced bipolar sensing may minimize the need for perioperative reprogramming while preserving intraoperative device operation.

Time to awakening after out-of-hospital cardiac arrest (OHCA) and post-resuscitation therapeutic hypothermia (TH) varies widely. We examined the time interval from when comatose OHCA patients were rewarmed to 37°C to when they showed definitive signs of neurological recovery and tried to identify potential predictors of awakening.With IRB approval, a retrospective case study was performed in OHCA patients who were comatose upon presentation to a community hospital during 2006-2010. They were treated with TH (target of 33°C) for 24h, rewarmed, and discharged alive. Comatose patients were generally treated medically after TH for at least 48h before any decision to withdraw supportive care was made. Pre-hospital TH was not used. Data are expressed as medians and interquartile range.The 89 patients treated with TH in this analysis were divided into three groups based upon the time between rewarming to 37°C and regaining consciousness. The 69 patients that regained consciousness in ≤48h after rewarming were termed "early-awakeners". Ten patients regained consciousness 48-72h after rewarming and were termed "intermediate-awakeners". Ten patients remained comatose and apneic72h after rewarming but eventually regained consciousness; they were termed "late-awakeners". The ages for the early, intermediate and late awakeners were 56 [49,65], 62 [48,74], and 58 [55,65] years, respectively. Nearly 67% were male. Following rewarming, the time required to regain consciousness for the early, intermediate and late awakeners was 9 [2,18] (range 0-47), 60.5 [56,64.5] (range 49-71), and 126 [104,151]h (range 73-259), respectively. Within 90 days of hospital admission, favorable neurological function based on a Cerebral Performance Category (CPC) score of 1 or 2 was reported in 67/69 early, 10/10 intermediate, and 8/10 late awakeners.Following OHCA and TH, arbitrary withdrawal of life support48h after rewarming may prematurely terminate life in many patients with the potential for full neurological recovery. Additional clinical markers that correlate with late awakening are needed to better determine when withdrawal of support is appropriate in OHCA patients who remain comatose48h after rewarming.

Out-patient pre-anaesthesia assessment needs to keep pace with the growing volume and complexity of the ambulatory surgery population. In order to maintain efficiency and patient safety while minimising delays and cancellations, out-patients are routinely screened pre-operatively with several methods. These include questionnaires, telephone interviews, automated interviews, and evaluation at a pre-anaesthesia assessment clinic. Information gained from the pre-anaesthesia screening is then used to order additional laboratory tests and consultations as necessary. Indiscriminate laboratory screening is expensive and of no proven benefit in the out-patient setting. The pre-anaesthesia assessment provides the opportunity to not only evaluate patients' medical conditions but to also discuss the anaesthetic plan, explain risks, and allay anxiety. Addressing these issues in a systematic manner helps to keep complication rates low while maintaining a high degree of efficiency and patient satisfaction.

The initial aim of the Berkeley Structural Genomics Center is to obtain a near-complete structural complement of two minimal organisms, closely related pathogens Mycoplasma genitalium and M. pneumoniae. The former has fewer than 500 genes and the latter fewer than 700 genes. To achieve this goal, the current protein targets have been selected starting with those predicted to be most tractable and likely to yield new structural and functional information. During the past 3 years, the semi-automated structural genomics pipeline has been set up from cloning, expression, purification, and ultimately to structural determination. The results from the pipeline substantially increased the coverage of the protein fold space of M. pneumoniae and M. genitalium. Furthermore, about 1/2 of the structures of ‘unique’ protein sequences revealed new and novel folds, and over 2/3 of the structures of previously annotated ‘hypothetical proteins’ inferred their molecular functions.

The need for non-operating room (OR) anesthesia services continues to expand as technology improves and the scope of procedures performed by cardiologists, radiologists, gastroenterologists, and other physicians grows. Indeed, the range of procedures that can now be performed safely and comfortably outside the OR is facilitated by many factors, not the least of which are improvements in sedation and anesthesia care. However, each of these non-OR settings has different needs and limitations. Delivering anesthesia in an operating room is a consistently structured endeavor irrespective of the specialty; a given OR can accommodate a wide variety of cases ranging from urologic surgery to neurosurgery. This is not the case in the non-OR setting; delivering anesthesia in a GI suite is qualitatively different than doing so in a cardiac catheterization lab—equipment is highly specialized, patient comorbidities are often unique to the particular specialty, physical access to the patient may vary, and the ‘‘culture’’ of the venue may make integration and communication difficult. For example, in the cardiac catheterization or EP lab, imaging equipment is often permanently affixed at the head of the bed, precluding easy access to the patient’s airway. Given the myriad screens and equipment around patients, there may be inadequate space for anesthesia equipment, especially when tables move to permit fluoroscopy. There may also be confusion as to the handling of lab specimens as well as communication of lab results to anesthesiologists if there is no standard protocol. Again, coping with these situations may be straightforward in an OR setting; outside the OR, however, basic work processes cannot be assumed. Work spaces are frequently retrofitted to accommodate anesthesia providers (and associated equipment) because procedural areas were not constructed with anesthesia delivery in mind. This often produces less-than-ideal working conditions for the anesthesia team. For example, medical specialists often dim ambient lights to accommodate digital images, making it difficult for the anesthesiologist to see equipment or observe patients. In addition, moribund patients deemed too sick to undergo an operation are often scheduled for a more limited procedure that nevertheless requires an anesthetic. The mix of unfamiliar work environment and processes along with a moribund patient can be especially problematic. However, anesthesia providers can help improve their work environment by becoming involved in the design phase of procedural facilities and also establishing working relationships with the subspecialty physicians. Indeed, as facilities are remodeled to accommodate the growing number of complex procedures performed outside the traditional confines of the OR, subspecialists increasingly are seeking the input of anesthesia care providers.

To determine the utility of preoperative screening electrocardiograms (ECGs) among ambulatory surgery patients, we reviewed the charts of 751 consecutive adult patients who underwent ambulatory surgery. Data were collected on demographic characteristics, coexisting medical problems, American Society of Anesthesiologists physical status score, preoperative ECG results, adverse intraoperative cardiovascular events, and postoperative cardiovascular complications. In our study population of relatively healthy outpatients, preoperative ECGs were abnormal in 42.7% of patients. Age, increased physical status score, and male gender were associated with a greater incidence of abnormal preoperative ECGs. There were 12 adverse cardiovascular perioperative events among the 751 patients (1.6%), and the preoperative ECG may have been clinically useful in six of these 12 patients. Neither preoperative ECGs nor results of preoperative screening questionnaires were predictive of adverse cardiovascular perioperative events. These findings question the utility of preoperative ECGs in the ambulatory surgery setting, especially among younger, relatively healthy patients. ( Arch Intern Med . 1992;152:301-305)