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This is a copy of the slides presented at the meeting but not formally written up for the volume.
At heterojunctions between different oxide perovskite phases both lattice and electronic structure is modified by the junction. One interesting question that several groups have studied is just how far into the neighboring materials these perturbations extend. We have studied this for insulating phases as well as conducting phases. For insulating phases it appears that the lattice distortions are healed in a layer about one unit cell thick. By stacking different materials each of which is only a single unit cell thick we have obtained materials that exhibit new properties determined by the stacking architecture. For example, superlattices that lack inversion symmetry have a built-in polarization that is controlled by the direction of the strain asymmetry. For conducting phases, the electronic structure also seems to be modified mainly in a layer only a few unit cells thick. We have studied this in superlattices of SrTiO3 and LaMnO3 in which we vary the thickness of the layers. We use optical conductivity to probe the electronic structure in the near infrared to near ultraviolet spectral region. The conductivity is close to the average of the two constituents, but differs in certain spectral regions, especially for the films with the thinnest supercells.This work was supported by the Department of Energy Basic Energy Sciences program at the Fredrick Seitz Materials Research Laboratory at the University of Illinois, Urbana, IL.
To study the clinical outcomes of a posterior nasoseptal flap used in the endonasal reconstruction of anterior skull base defects.
The early harvested flap was used to reconstruct anterior skull base defects in patients with high-flow on-table cerebrospinal fluid leak. Post-operatively, the patients were analysed for cerebrospinal fluid leak and bleeding.
Of the 100 patients, 87 had macro defects while 13 had micro defects. Non-secretary lesions were present in 60 patients, while secretary lesions were present in 40 patients. Cerebrospinal fluid leak was present in all the patients undergoing surgery, and the majority of them had a lumbar drain fitted. Post-operatively, two patients experienced bleeding and only two patients had a cerebrospinal fluid leak.
The use of a posterior nasoseptal flap for reconstruction of the anterior skull base amongst patients with a high-flow intra-operative cerebrospinal fluid leak can help prevent post-operative cerebrospinal fluid leak. Its applicability to wide patient profiles, with respect to age, size of defect and diagnosis, make it a versatile choice for reconstruction after endonasal anterior skull base surgical procedures.
Introduction: Intranasal dexmedetomidine (IND) is an emerging agent for procedural distress in children. However, studies to date have been limited by small samples and imprecise estimates of effect size. We sought to summarize the evidence on the effectiveness of IND for procedures associated with distress in children. Methods: We performed electronic searches of MEDLINE (1946-2018), EMBASE (1980-2018), Google Scholar (2018), CINAHL (1981-2018), Cochrane Central Register of Controlled Trials (2018), 6 clinical trials registries and conference proceedings (2010-2018). Title searches, data abstraction, and risk of bias assessments were performed in duplicate. We included all published and unpublished, randomized and quasi-randomized trials of IND for procedures in children younger than 19 years of age without language restriction. The methodological quality of studies was evaluated using the Cochrane Collaboration's Risk of Bias tool. The primary outcome was the proportion of participants that were deemed to be adequately sedated for the procedure. Results: Of 661 studies, 18 met inclusion criteria. Trials involved 2128 participants, age 1 month - 14 years (836, 39.3% females), who received IND 1 - 4 mcg/kg either by drops (n = 12), atomizer (n = 4), or both (n = 2). 12 trials were eligible for meta-analysis. 13 trials used validated instruments to assess sedation. All studies except one were associated with low or moderate risk of bias. For painful procedures (IV insertion; laceration repair; dental extraction), the pooled OR (95% CI) for adequate sedation and need for additional analgesia was non-significant [1.19 (0.53, 2.65)] and [2.16 (0.62, 7.49)], respectively (n = 5). For non-painful procedures (diagnostic imaging), the corresponding pooled OR (95% CI) favored IND [3.04 (1.58, 5.82)] and [4.44 (2.11, 9.35)], respectively (n = 7). Time to onset and duration of sedation ranged from 13-31 minutes and 41-91.5 minutes, respectively. For adverse effects, the pooled OR (95% CI) was not significantly different between IND and comparators [0.58 (0.22, 1.55] and there were no serious adverse events. Conclusion: IND at doses 1 to 4 mcg/kg are safe and adequately sedate children undergoing non-painful procedures, although the ease of administration must be weighed against the risk of prolonged sedation. Additional trials with larger sample sizes and greater methodologic rigor are needed for painful emergency department procedures such as laceration repair and IV insertion.
The Navigation with Indian Constellation (NavIC)/Indian Regional Navigation Satellite System (IRNSS) is an emerging satellite navigation system that provides an independent navigation system for positioning and timing services in India and up to 1,500 km from its borderline. The dual frequency NavIC system uses the L5 frequency and S-band for navigation. These navigation signals are extremely weak and susceptible to interference when they are received on Earth's surface. Moreover, the performance of these bands may be degraded by other band or out-of-band communication systems, which can become the major threat to the performance of a NavIC receiver. The main focus of this paper is to detect real-time interference of Wi-Fi signals in the S-band of the NavIC receiver. The results are prepared with respect to the Power Spectral Density (PSD), execution of acquisition stage and the detection of Wi-Fi interference with two sample hypothesis testing methods including the Kolmogorov-Smirnov (KS)-test, the t-test and the Variance (var)-test. A performance analysis of the p-value is used to measure the evidence of interference existence for hypothesis testing, decision hypothesis and probability of detection are evaluated for each hypothesis method. The results show the severity of the Wi-Fi signal as a potential source of interference for future NavIC applications.
Ischemic stroke treatment is time-sensitive, and barriers to providing prehospital care encountered by Emergency Medical Services (EMS) providers have been under-studied.
This study described barriers to providing prehospital care, identified predictors of these barriers, and assessed the impact of these barriers on EMS on-scene time and administration of tissue plasminogen activator (tPA) in the emergency department (ED).
A retrospective cohort study was performed using the Get With The Guidelines-Stroke (GWTG-S; American Heart Association [AHA]; Dallas, Texas USA) registry at two hospitals to identify ischemic stroke patients arriving by EMS. Variables were abstracted from prehospital and hospital medical records and merged with registry data. Barriers to care were grouped into themes. Logistic regression was used to identify predictors of barriers to care, and bi-variate tests were used to assess differences in EMS on-scene time and the proportion of patients receiving tPA between patients with and without barriers.
Barriers to providing prehospital care were documented for 15.5% of patients: 29.6% related to access, 26.7% communication, 23.0% extrication and transportation, 20.0% refusal, and 14.1% assessment/management. Non-white and non-black race (OR: 3.69; 95% CI, 1.63-8.36) and living alone (OR: 1.53; 95% CI, 1.05-2.23) were associated with greater odds of barriers to providing care. The EMS on-scene time was ≥15 minutes for 70.4% of patients who had a barrier to care, compared with 49.0% of patients who did not (P<.001). There was no significant difference in the proportion of patients who were administered tPA between those with and without barriers to care (14.1% vs 19.2%; P=.159).
Barriers to providing prehospital care were documented for a sizable proportion of ischemic stroke patients, with the majority related to patient access and communication, and occurred more frequently among non-white and non-black patients and those living alone. Although EMS on-scene time was longer for patients with barriers to care, the proportion of patients receiving tPA in the ED did not differ.
LiT, CushmanJT, ShahMN, KellyAG, RichDQ, JonesCMC. Barriers to Providing Prehospital Care to Ischemic Stroke Patients: Predictors and Impact on Care. Prehosp Disaster Med.2018;33(5):501–507.
Patients with chronic liver disease (CLD) have frequent exposure to Clostridium difficile infection (CDI) risk factors but the incidence and aetiology of CDI on this population is poorly understood. The aim of this study was to assess the incidence, disease presentation and outcomes of CDI in patients with underlying CLD. The Health Care and Utilization Project National Inpatient Sample (HCUP-NIS) 2009 dataset was used to identify patients with CLD who developed CDI along with matched non-CLD patients with CDI. Using the NIS dataset, the incidence rate of CDI was 189.4/10 000 discharges in CLD patients vs. 83.7/10 000 discharges in the non-CLD matched cohort (P < 0.001). Compared with non-CLD, comorbidity-matched controls with CDI, CLD patients with CDI had higher likelihood of in-hospital mortality (8.8% vs. 18.6%, P < 0.001), increased length of stay by 1.19 days (P < 0.001) and increased total costs by $8632 (P < 0.001). In separate analyses using a tertiary case database of hospitalised patients in Houston, Texas (2006–2016) with CLD and CDI (n = 41) compared with patients with CDI but not CLD (n = 111), CLD patients had significantly higher Charlson comorbidity index (P < 0.0001) but similar risk factors for CDI and CDI-related disease presentation compared with non-CLD patients. In conclusion, CDI-related risk factors were almost universally present in the CLD population. CDI resulted in worse outcomes in this population.
Bioprinting, the three-dimensional (3D) printing of cell-laden inks, will be a truly revolutionary technology for the biomaterials community. The number of bioink studies, especially aimed at functional tissues, remains significantly limited, and furthermore, current bioinks are limited by a narrow window of printability. This can be largely attributed to the fact that the preparation of bioinks and their 3D printing is significantly complicated by the presence of cells, which require strict conditions for their viability. This article discusses how cells should be considered during bioink synthesis, 3D printing, and post-printing processing. We also discuss what has been reported thus far with regard to the relationships between bioink material properties and cells. This underlines the need for next-generation bioinks that simultaneously achieve excellent printability, high cell viability, and a wide range of material properties.
Determining the most appropriate level of care for patients in the prehospital setting during medical emergencies is essential. A large body of literature suggests that, compared with Basic Life Support (BLS) care, Advanced Life Support (ALS) care is not associated with increased patient survival or decreased mortality. The purpose of this special report is to synthesize the literature to identify common study design and analytic challenges in research studies that examine the effect of ALS, compared to BLS, on patient outcomes. The challenges discussed in this report include: (1) choice of outcome measure; (2) logistic regression modeling of common outcomes; (3) baseline differences between study groups (confounding); (4) inappropriate statistical adjustment; and (5) inclusion of patients who are no longer at risk for the outcome. These challenges may affect the results of studies, and thus, conclusions of studies regarding the effect of level of prehospital care on patient outcomes should require cautious interpretation. Specific alternatives for avoiding these challenges are presented.
LiT, JonesCMC, ShahMN, CushmanJT, JuskoTA. Methodological Challenges in Studies Comparing Prehospital Advanced Life Support with Basic Life Support. Prehosp Disaster Med. 2017;32(4):444–450.
Large-scale studies evaluating risk factors for Clostridium difficile infection (CDI), a leading cause of infectious diarrhea among patients undergoing stem cell transplantation (SCT), are lacking. We have evaluated risk factors for CDI among both autologous SCT (auto-SCT), and allogeneic SCT (allo-SCT) recipients using the National Inpatient Sample (NIS) database provided by the Healthcare Cost and Utilization Project (HCUP).
We used patient data obtained from the NIS database for all adult patients admitted for auto- and allo-SCTs from January 2001 to December 2010. We performed multivariate logistic regression analyses to evaluate risk factors of CDI in auto- and allo-SCT patients.
Auto-SCTs constituted 61.5% of all SCTs performed during the study period. Of the 53,072 auto-SCT patients, 5.8% had CDI, whereas 8.5% of 33,189 allo-SCT patients had CDI. Univariate analyses identified age, gender, indication for SCT, radiation as part of the conditioning regimen, respiratory failure, septicemia, lengthy hospital stay, and multiple comorbidities as risk factors for CDI in both subsets. On multivariate analyses for auto-SCT, there was significant correlation between age and the indication for transplant (P=.003), but the indication for either auto- or allo-SCT was not associated with CDI on multivariate analyses. The following factors were found to be associated with CDI: septicemia (auto-SCT odds ratio [OR],=1.64; 95% confidence interval [CI], 1.35–2; and allo-SCT OR, 1.69; 95% CI, 1.36–2.1), male gender (auto-SCT OR, 1.29; 95% CI, 1.09–1.53; and allo-SCT OR, 1.36; 95% CI, 1.18–1.57), lengthy hospital stay (auto-SCT OR, 2.81; 95% CI, 2.29–3.45; and allo-SCT OR, 2.63; 95% CI, 2.15–3.22), and presence of multiple comorbidities (auto-SCT OR, 1.32; 95% CI, 1.11–1.57; and allo-SCT OR, 1.18; 95% CI, 1.0–1.4).
The prevalence of CDI was higher among patients undergoing allo-SCT. CDI was significantly associated with longer hospital stay, septicemia, and male gender for auto- and allo-SCT recipients. While this analysis did not permit us to directly ascribe the associations to be causative for CDI, it identifies the more vulnerable population for CDI and provides a rationale for the development of more effective approaches to preventing CDI.
The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
Previous studies have found that older adults are more likely to use Emergency Medical Services (EMS) than younger adults, but the reasons for this remain understudied.
This study aimed to determine if older age is associated with using EMS for transportation to an emergency department (ED) after controlling for confounding variables.
A cross-sectional survey study was conducted at a large academic medical center. Data on previous medical history, chief complaint, self-perceived illness severity, demographic information, and mode of arrival to the ED were collected on all subjects. Those who arrived to the ED via EMS also were asked reasons why they opted to call an ambulance for their illness/injury. Descriptive statistics were used to quantify survey responses, and multivariable regression was used to assess the independent effect of age on mode of ED arrival.
Data from 1,058 subjects were analyzed, 449 (42%) of whom arrived to the ED via EMS. Compared to adults<55 years, the unadjusted prevalence ratio for the association between age and EMS use was 1.18 (95% CI, 0.96-1.45) for subjects 55-79 years and 1.54 (95% CI, 1.18-2.02) for subjects ≥80 years. After adjustment for confounding variables, age remained a statistically significant risk factor for EMS use (P<.05).
Older age is an independent risk factor for transportation to the ED via ambulance; however, this effect is attenuated by number of chronic medical conditions and history of depression. Additional research is needed to account for confounders unmeasured in this study and to elucidate reasons for the increased frequency of EMS use among older adults.
JonesCMC, WassermanEB, LiT, AmidonA, AbbottM, ShahMN. The Effect of Older Age on EMS Use for Transportation to an Emergency Department. Prehosp Disaster Med. 2017;32(3):261–268.
The Learning Health System Network clinical data research network includes academic medical centers, health-care systems, public health departments, and health plans, and is designed to facilitate outcomes research, pragmatic trials, comparative effectiveness research, and evaluation of population health interventions.
The Learning Health System Network is 1 of 13 clinical data research networks assembled to create, in partnership with 20 patient-powered research networks, a National Patient-Centered Clinical Research Network.
Results and Conclusions
Herein, we describe the Learning Health System Network as an emerging resource for translational research, providing details on the governance and organizational structure of the network, the key milestones of the current funding period, and challenges and opportunities for collaborative science leveraging the network.
We study the problem of mass transport to surfaces with heterogeneous reaction rates in the presence of shear flow over these surfaces. The reactions are first order and the heterogeneity is due to the existence of inert regions on the surfaces. Such problems are ubiquitous in the field of heterogeneous catalysis, electrochemistry and even biological mass transport. In these problems, the microscale reaction rate is characterized by a Damköhler number
, while the Péclet number
is the dimensionless ratio of the bulk shear rate to the inverse diffusion time scale. The area fraction of the reactive region is denoted by
. The objective is to calculate the yield of reaction, which is directly related to the mass flux to the reactive region, denoted by the dimensionless Sherwood number
. Previously, we used boundary element simulations and examined the case of first-order reactive disks embedded in an inert surface (Shah & Shaqfeh J. Fluid Mech., vol. 782, 2015, pp. 260–299). Various correlations for the Sherwood number as a function of
were obtained. In particular, we demonstrated that the ‘method of additive resistances’ provides a good approximation for the Sherwood number for a wide range of values of
, the reactive disks are in a close packed configuration where the inert regions are essentially disconnected from each other. In this work, we develop an understanding of the physics when
, by examining the inverse problem of inert disks on a reactive surface. We show that the method of resistances approach to obtain the Sherwood number fails in the limit as
, i.e. in the dilute limit of periodic inert disks, due to the existence of a surface concentration boundary layer around each disk that scales with (
). This boundary layer controls the screening length between inert disks and allows us to introduce a new theory, thus providing new correlations for the Sherwood number that are highly accurate in the limit of
Experiments on the National Ignition Facility show that multi-dimensional effects currently dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seeded by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of inertial confinement fusion implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. LANL has adopted three main approaches to develop a one-dimensional (1D) implosion platform where 1D means measured yield over the 1D clean calculation. A high adiabat, low convergence platform is being developed using beryllium capsules enabling larger case-to-capsule ratios to improve symmetry. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the implosion convergence can be controlled via the initial vapor pressure set by the target fielding temperature. The last method is double shell targets. For double shells, the smaller inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. However, double shell targets have a different set of trade-off versus advantages. Details for each of these approaches are described.
Curcumin therapy in animals has produced positive cognitive and behavioural outcomes; results of human trials, however, have been inconsistent. In this study, we report the results of a 12-month, randomised, placebo-controlled, double-blind study that investigated the ability of a curcumin formulation to prevent cognitive decline in a population of community-dwelling older adults. Individuals (n 96) ingested either placebo or 1500 mg/d BiocurcumaxTM for 12 months. A battery of clinical and cognitive measures was administered at baseline and at the 6-month and 12-month follow-up assessments. A significant time×treatment group interaction was observed for the Montreal Cognitive Assessment (repeated-measures analysis; time×treatment; F=3·85, P<0·05). Subsequent analysis revealed that this association was driven by a decline in function of the placebo group at 6 months that was not observed in the curcumin treatment group. No differences were observed between the groups for all other clinical and cognitive measures. Our findings suggest that further longitudinal assessment is required to investigate changes in cognitive outcome measures, ideally in conjunction with biological markers of neurodegeneration.
“Solar X-ray Spectrometer (SOXS)” mission on-board GSAT-2 Indian spacecraft was launched on 08 May 2003 by GSLV-D2 and deployed in geostationery orbit to study the X-ray emission from solar flares with high spectral and temporal resolution. The SOXS consists of two independent payloads viz. SOXS Low Energy Detector (SLD) payload, and SOXS High Energy Detector (SHD) payload. The SLD consists of two solid state detectors Si PIN and CZT, which cover the energy range from 4-60 keV, while the SHD has NaI(Tl)/CsI(Na) sandwiched phoswich detector that covers energy range from 20 keV to 10 MeV. We present very briefly the science objectives and instrumentation of SLD payload. After the successful In-orbit Tests (IOT), the first light was fed into SLD payload on 08 June 2003 when the solar flare was already in progress. We briefly present the first results from the SLD payload.
Curcumin derived from turmeric is well documented for its anti-carcinogenic, antioxidant and anti-inflammatory properties. Recent studies show that curcumin also possesses neuroprotective and cognitive-enhancing properties that may help delay or prevent neurodegenerative diseases, including Alzheimer’s disease (AD). Currently, clinical diagnosis of AD is onerous, and it is primarily based on the exclusion of other causes of dementia. In addition, phase III clinical trials of potential treatments have mostly failed, leaving disease-modifying interventions elusive. AD can be characterised neuropathologically by the deposition of extracellular β amyloid (Aβ) plaques and intracellular accumulation of tau-containing neurofibrillary tangles. Disruptions in Aβ metabolism/clearance contribute to AD pathogenesis. In vitro studies have shown that Aβ metabolism is altered by curcumin, and animal studies report that curcumin may influence brain function and the development of dementia, because of its antioxidant and anti-inflammatory properties, as well as its ability to influence Aβ metabolism. However, clinical studies of curcumin have revealed limited effects to date, most likely because of curcumin’s relatively low solubility and bioavailability, and because of selection of cohorts with diagnosed AD, in whom there is already major neuropathology. However, the fresh approach of targeting early AD pathology (by treating healthy, pre-clinical and mild cognitive impairment-stage cohorts) combined with new curcumin formulations that increase bioavailability is renewing optimism concerning curcumin-based therapy. The aim of this paper is to review the current evidence supporting an association between curcumin and modulation of AD pathology, including in vitro and in vivo studies. We also review the use of curcumin in emerging retinal imaging technology, as a fluorochrome for AD diagnostics.
To report the International Nosocomial Infection Control Consortium surveillance data from 40 hospitals (20 cities) in India 2004–2013.
Surveillance using US National Healthcare Safety Network’s criteria and definitions, and International Nosocomial Infection Control Consortium methodology.
We collected data from 236,700 ICU patients for 970,713 bed-days
Pooled device-associated healthcare-associated infection rates for adult and pediatric ICUs were 5.1 central line–associated bloodstream infections (CLABSIs)/1,000 central line–days, 9.4 cases of ventilator-associated pneumonia (VAPs)/1,000 mechanical ventilator–days, and 2.1 catheter-associated urinary tract infections/1,000 urinary catheter–days
In neonatal ICUs (NICUs) pooled rates were 36.2 CLABSIs/1,000 central line–days and 1.9 VAPs/1,000 mechanical ventilator–days
Extra length of stay in adult and pediatric ICUs was 9.5 for CLABSI, 9.1 for VAP, and 10.0 for catheter-associated urinary tract infections. Extra length of stay in NICUs was 14.7 for CLABSI and 38.7 for VAP
Crude extra mortality was 16.3% for CLABSI, 22.7% for VAP, and 6.6% for catheter-associated urinary tract infections in adult and pediatric ICUs, and 1.2% for CLABSI and 8.3% for VAP in NICUs
Pooled device use ratios were 0.21 for mechanical ventilator, 0.39 for central line, and 0.53 for urinary catheter in adult and pediatric ICUs; and 0.07 for mechanical ventilator and 0.06 for central line in NICUs.
Despite a lower device use ratio in our ICUs, our device-associated healthcare-associated infection rates are higher than National Healthcare Safety Network, but lower than International Nosocomial Infection Control Consortium Report.
Infect. Control Hosp. Epidemiol. 2016;37(2):172–181