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PD patients commonly exhibit executive dysfunction early in the disease course which may or may not predict further cognitive decline over time. Early emergence of visuospatial and memory impairments, in contrast, are more consistent predictors of an evolving dementia syndrome. Most prior studies using fMRI have focused on mechanisms of executive dysfunction and have demonstrated that PD patients exhibit hyperactivation that is dependent on the degree of cognitive impairment, suggestive of compensatory strategies. No study has evaluated whether PD patients with normal cognition (PD-NC) and PD patients with Mild Cognitive Impairment (PD-MCI) exhibit compensatory activation patterns during visuospatial task performance.
Participants and Methods:
10 PD-NC, 12 PD-MCI, and 14 age and sex-matched healthy controls (HC) participated in the study. PD participants were diagnosed with MCI based on the Movement Disorders Society Task Force, Level II assessment (comprehensive assessment). Functional magnetic resonance imaging (fMRI) was performed during a motion discrimination task that required participants to identify the direction of horizontal global coherent motion embedded within dynamic visual noise under Low and High coherence conditions. Behavioral accuracy and functional activation were evaluated using 3 * 2 analyses of covariance (ANCOVAs) (group [HC, PD-NC, PD-MCI] * Coherence [High vs. Low]) accounting for age, sex, and education. Analyses were performed in R (v4.1.2(Team, 2013)).
Results:
PD-MCI (0.702± 0.269) patients exhibited significantly lower accuracy on the motion discrimination task than HC (0.853 ± 0.241; p = 0.033) and PD-NC (0.880 ± 0.208; p =0.039). A Group * Coherence interaction was identified in which several regions, including orbitofrontal, posterior parietal and occipital cortex, showed increased activation during High relative to Low coherence trials in the PD patient groups but not in the HC group. HC showed default mode deactivation and frontal-parietal activation during Low relative to High coherence trials that was not evident in the patient groups.
Conclusions:
PD-MCI patients exhibited worse visuospatial performance on a motion discrimination task than PD-NC and HC participants and exhibited hyperactivation of the posterior parietal and occipital regions during motion discrimination, suggesting possible compensatory activation.
Clinical trials face many challenges with meeting projected enrollment and retention goals. A study’s recruitment materials and messaging convey necessary key information and therefore serve as a critical first impression with potential participants. Yet study teams often lack the resources and skills needed to develop engaging, culturally tailored, and professional-looking recruitment materials. To address this gap, the Recruitment Innovation Center recently developed a Recruitment & Retention Materials Content and Design Toolkit, which offers research teams guidance, actionable tips, resources, and customizable templates for creating trial-specific study materials. This paper seeks to describe the creation and contents of this new toolkit.
OBJECTIVES/GOALS: The rates of computational phenotyping algorithm reuse across health systems are low, leading to a proliferation of algorithms for the same trait. We propose a framework for reusing computational phenotyping algorithms and describe the real-world deployment of this framework for the development of the Colorado Diabetes EHR Research Repository. METHODS/STUDY POPULATION: The novel phenotype reuse framework consists of 4 steps: select algorithms that are appropriate for reuse by assessing whether they are fit for purpose; extend the algorithm to account for changes in data and care practice standards; localize the algorithm to use local database standards and terminologies; optimize the algorithm by applying a data driven approach to achieve the desired local performance. To identify individuals with type 1 diabetes (T1D) or type 2 diabetes (T2D), we selected and implemented T2D algorithms in a cohort of adults with any diabetes or pre-diabetes related diagnosis code, medication, or abnormal glucose-related laboratory test in the clinical data warehouse for UCHealth and the University of Colorado. RESULTS/ANTICIPATED RESULTS: We included a total of 926,290 patients who were identified by initial filters. Patients were more likely to be female (53%), identify as non-Hispanic white (69%) and had a median age of 58 years (IQR: 41, 70). Implementation, extension, localization, & optimization through iterative chart review prioritized high sensitivity for all-cause diabetes and high specificity for T1D and T2D. Of the original cohort, 252,946 (27%) were identified by the all-cause diabetes algorithm. Of these 11,688 were identified as T1D and 135,588 as T2D. After optimization the all-cause diabetes algorithm had 88% sensitivity, 90% specificity, 74% positive predictive value (PPV), and 96% negative predictive value (NPV). Our algorithms for T1D and T2D had high specificity (100% and 99%, respectively) and PPV (100 and 96% respectively). DISCUSSION/SIGNIFICANCE: Developing computational phenotyping algorithms is expensive and time consuming, yet algorithm reuse is low due to a lack of practical approaches for reusing algorithms. We demonstrate application of a novel framework for algorithm reuse, yielding good alignment of algorithm performance with study goals for identifying individuals with diabetes.
Several studies have shown that finishing bulls kept in housing systems with fully slatted concrete floors are impaired in their lying behaviour and locomotion due to the hardness and slipperiness of the ground. The aim of this study was to investigate the effects of floor quality (straw-bedded lying area, rubber-coated slats, concrete slats) on the lying behaviour of finishing bulls. The floor type did not influence the total lying duration, but the number of lying bouts and the number of short standing periods decreased with increasing hardness of the floor in the lying area. In addition, bulls showed more interrupted lying-down and standing-up movements on concrete and rubber-coated slats than on straw bedding. On the other hand, atypical lying-down and standing-up instances, slipping and falling were reduced on rubber-coated slats and on straw bedding compared to concrete slats. Displacements of lying animals were observed more often on rubber-coated slats than on concrete slats or straw bedding. In conclusion, rubber-coated slats improve traction on the ground but are not able to provide as soft a lying area as straw bedding. Rubber coating can thus serve to improve welfare for finishing bulls kept on concrete slats but cannot be considered equivalent to straw bedding.
To assess preventability of hospital-onset bacteremia and fungemia (HOB), we developed and evaluated a structured rating guide accounting for intrinsic patient and extrinsic healthcare-related risks.
Design:
HOB preventability rating guide was compared against a reference standard expert panel.
Participants:
A 10-member panel of clinical experts was assembled as the standard of preventability assessment, and 2 physician reviewers applied the rating guide for comparison.
Methods:
The expert panel independently rated 82 hypothetical HOB scenarios using a 6-point Likert scale collapsed into 3 categories: preventable, uncertain, or not preventable. Consensus was defined as concurrence on the same category among ≥70% experts. Scenarios without consensus were deliberated and followed by a second round of rating.
Two reviewers independently applied the rating guide to adjudicate the same 82 scenarios in 2 rounds, with interim revisions. Interrater reliability was evaluated using the κ (kappa) statistic.
Results:
Expert panel consensus criteria were met for 52 scenarios (63%) after 2 rounds.
After 2 rounds, guide-based rating matched expert panel consensus in 40 of 52 (77%) and 39 of 52 (75%) cases for reviewers 1 and 2, respectively. Agreement rates between the 2 reviewers were 84% overall (κ, 0.76; 95% confidence interval [CI], 0.64–0.88]) and 87% (κ, 0.79; 95% CI, 0.65–0.94) for the 52 scenarios with expert consensus.
Conclusions:
Preventability ratings of HOB scenarios by 2 reviewers using a rating guide matched expert consensus in most cases with moderately high interreviewer reliability. Although diversity of expert opinions and uncertainty of preventability merit further exploration, this is a step toward standardized assessment of HOB preventability.
Retrospective self-report is typically used for diagnosing previous pediatric traumatic brain injury (TBI). A new semi-structured interview instrument (New Mexico Assessment of Pediatric TBI; NewMAP TBI) investigated test–retest reliability for TBI characteristics in both the TBI that qualified for study inclusion and for lifetime history of TBI.
Method:
One-hundred and eight-four mTBI (aged 8–18), 156 matched healthy controls (HC), and their parents completed the NewMAP TBI within 11 days (subacute; SA) and 4 months (early chronic; EC) of injury, with a subset returning at 1 year (late chronic; LC).
Results:
The test–retest reliability of common TBI characteristics [loss of consciousness (LOC), post-traumatic amnesia (PTA), retrograde amnesia, confusion/disorientation] and post-concussion symptoms (PCS) were examined across study visits. Aside from PTA, binary reporting (present/absent) for all TBI characteristics exhibited acceptable (≥0.60) test–retest reliability for both Qualifying and Remote TBIs across all three visits. In contrast, reliability for continuous data (exact duration) was generally unacceptable, with LOC and PCS meeting acceptable criteria at only half of the assessments. Transforming continuous self-report ratings into discrete categories based on injury severity resulted in acceptable reliability. Reliability was not strongly affected by the parent completing the NewMAP TBI.
Conclusions:
Categorical reporting of TBI characteristics in children and adolescents can aid clinicians in retrospectively obtaining reliable estimates of TBI severity up to a year post-injury. However, test–retest reliability is strongly impacted by the initial data distribution, selected statistical methods, and potentially by patient difficulty in distinguishing among conceptually similar medical concepts (i.e., PTA vs. confusion).
ENT presentations are prevalent in clinical practice but feature little in undergraduate curricula. Consequently, most medical graduates are not confident managing common ENT conditions. In 2014, the first evidence-based ENT undergraduate curriculum was published to guide medical schools.
Objective
To assess the extent that current UK medical school learning outcomes correlate with the syllabus of the ENT undergraduate curriculum.
Method
Two students from each participating medical school independently reviewed all ENT-related curriculum documents to determine whether learning outcomes from the suggested curriculum were met.
Results
Sixteen of 34 curricula were reviewed. Only a minority of medical schools delivered teaching on laryngectomy or tracheostomy, nasal packing or cautery, and ENT medications or surgical procedures.
Conclusion
There is wide variability in ENT undergraduate education in UK medical schools. Careful consideration of which topics are prioritised, and the teaching modalities utilised, is essential. In addition, ENT learning opportunities for undergraduates outside of the medical school curriculum should be augmented.
Life events play a role in the development of childhood depression. According to the literature major depression lowers subjective quality of life (QL). There are few studies about factors decreasing QL in general and even less on child and adolescent samples. The relationship between mental disorders and QL is not well studied either. In the present research we studied the quality of life in a school population and the relationship of QL to the number of stressful life events (SLE) and the severity of depressive symptoms.
Methods:
The sample consisted of 9 elementary schools in Hungary. 2620 children were tested between 7-15 years of age (mean age: 10.45 years (s.d. 2.2). There were 1160 boys (44%) and 1460 girls (56%). Stressful life events were collected by parental report, depressive symptoms were assessed by short version of CDI, quality of life was measured by self-report and parental questionnaires (ILK).
Results:
Both stressful life events and depressive symptoms have a significant negative effect on subjective QL overall and individual QL domains. The effect of depressive symptom severity is much larger than that of the SLE. When comparing the parent and child opinions about the QL of the child, we can see that depressive symptoms are more important in childrens' opinion while SLE is more negative in parents' opinion. Stressful life events effect subjective QL directly (50%), indirectly (50%) through depressive symptoms. A complex study of the QL in childhood onset mental disorders would be important.
There is growing concern over a future shortfall in provision of UK otolaryngology consultants. There is a declining rate of applications to otolaryngology specialty training in the UK.
Objective
This study aimed to systematically review the literature to establish what factors influence medical students’ and junior doctors’ decision to pursue a career in otolaryngology.
Method
Medline, Embase and PubMed databases were searched in January 2019. Additional manual reference checks of identified literature were performed.
Results
Eleven articles were included in the review. Common factors that positively influenced the decision to pursue a career in otolaryngology were exposure to the specialty, positive role models and a good work-life balance. Lack of exposure was a consistent deterrent from pursuing a career in otolaryngology.
Conclusion
This review reiterates the need for greater exposure to otolaryngology in the undergraduate curriculum. In addition, mentorship for students with an interest in otolaryngology should be a priority.
Determine the effectiveness of a personal protective equipment (PPE)-free zone intervention on healthcare personnel (HCP) entry hand hygiene (HH) and PPE donning compliance in rooms of patients in contact precautions.
Design:
Quasi-experimental, multicenter intervention, before-and-after study with concurrent controls.
Setting:
All patient rooms on contact precautions on 16 units (5 medical-surgical, 6 intensive care, 5 specialty care units) at 3 acute-care facilities (2 academic medical centers, 1 Veterans Affairs hospital). Observations of PPE donning and entry HH compliance by HCP were conducted during both study phases. Surveys of HCP perceptions of the PPE-free zone were distributed in both study phases.
Intervention:
A PPE-free zone, where a low-risk area inside door thresholds of contact precautions rooms was demarcated by red tape on the floor. Inside this area, HCP were not required to wear PPE.
Results:
We observed 3,970 room entries. HH compliance did not change between study phases among intervention units (relative risk [RR], 0.92; P = .29) and declined in control units (RR, 0.70; P = .005); however, the PPE-free zone did not significantly affect compliance (P = .07). The PPE-free zone effect on HH was significant only for rooms on enteric precautions (P = .008). PPE use was not significantly different before versus after the intervention (P = .15). HCP perceived the zone positively; 65% agreed that it facilitated communication and 66.8% agreed that it permitted checking on patients more frequently.
Conclusions:
HCP viewed the PPE-free zone favorably and it did not adversely affect PPE or HH compliance. Future infection prevention interventions should consider the complex sociotechnical system factors influencing behavior change.
We present very detailed images of the photosphere of an AGB star obtained with the PIONIER instrument, installed at the Very Large Telescope Interferometer (VLTI). The images show a well defined stellar disc populated by a few convective patterns. Thanks to the high precision of the observations we are able to derive the contrast and granulation horizontal scale of the convective pattern for the first time in a direct way. Such quantities are then compared with scaling relations between granule size, effective temperature, and surface gravity that are predicted by simulations of stellar surface convection.
To test the hypothesis that long-term care facility (LTCF) residents with Clostridium difficile infection (CDI) or asymptomatic carriage of toxigenic strains are an important source of transmission in the LTCF and in the hospital during acute-care admissions.
Design
A 6-month cohort study with identification of transmission events was conducted based on tracking of patient movement combined with restriction endonuclease analysis (REA) and whole-genome sequencing (WGS).
Setting
Veterans Affairs hospital and affiliated LTCF.
Participants
The study included 29 LTCF residents identified as asymptomatic carriers of toxigenic C. difficile based on every other week perirectal screening and 37 healthcare facility-associated CDI cases (ie, diagnosis >3 days after admission or within 4 weeks of discharge to the community), including 26 hospital-associated and 11 LTCF-associated cases.
Results
Of the 37 CDI cases, 7 (18·9%) were linked to LTCF residents with LTCF-associated CDI or asymptomatic carriage, including 3 of 26 hospital-associated CDI cases (11·5%) and 4 of 11 LTCF-associated cases (36·4%). Of the 7 transmissions linked to LTCF residents, 5 (71·4%) were linked to asymptomatic carriers versus 2 (28·6%) to CDI cases, and all involved transmission of epidemic BI/NAP1/027 strains. No incident hospital-associated CDI cases were linked to other hospital-associated CDI cases.
Conclusions
Our findings suggest that LTCF residents with asymptomatic carriage of C. difficile or CDI contribute to transmission both in the LTCF and in the affiliated hospital during acute-care admissions. Greater emphasis on infection control measures and antimicrobial stewardship in LTCFs is needed, and these efforts should focus on LTCF residents during hospital admissions.
Coinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.
A multi-scale analysis, ranging from μm → nm → Å-scaie on the influence of thermal treatment on the thermotropic copolyester based on 60 mol% (l,4)-hydroxybenzoic acid (B), 5 mol% (2,6)-hydroxynaphthoic acid (N), 17.5 mol% terephthalic acid (T) and 17.5 mol% biphenol (BP) - COTBP- was carried out. The Å and nm-scale structure was investigated by synchrotron scattering (WAXS and SAXS). Extruded tapes ca. 30 μm thick were annealed at 300 °C under air, without tension. WAXS revealed fibre-like structure with crystalline order, whereas SAXS patterns exhibited diamond-shaped diffuse scattering and discrete meridional scattering elucidating structures along the fibre axis and periodic crystallites. Heat treatment produced roughness reduction, and WAXS patterns showed reflections sharpening indicating an improvement of molecular register and packing (molecular alignment and degree of crystallinity Χ increased). Thermal treatment increased the thermal stability, melting transition and tensile Young’s modulus, E, along extrusion axis, whereas nanoindentation showed decrease of hardness and elastic modulus. Hence, a thermally-induced seif-reinforcing effect was evidenced, with microstructure reorganization correlating with improved thermo-mechanical properties.
The paper analyzes the issues relating to the applicability of innovative material systems for flexible composite armors. The authors made several samplings of aramid fibers (Kevlar 49) by replacing the epoxy resin base, which is often described in the literature, with the thermoplastic matrix - polyethylene (HDPE) and polypropylene (PP). The samples were fired with .38 Special Full Metal Jacketed (FMJ) ammunition produced by the S&B Company, and then the process of firing was modeled in the ABAQUS program. The advantages and disadvantages of the new material system including the possibility of its use in the construction of hybrid composite armors have been presented on the basis of the results of numerical analyses and ballistic tests.
from
Part IV
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Experimental Comparisons of Auction Designs
By
Martin Bichler, Department of Informatics, Technical University of Munich,
Jacob K. Goeree, School of Economics, UNSW Business School,
Stefan Mayer, Department of Informatics, Technical University of Munich,
Pasha Shabalin, Astradi
The 1994 sale of radio spectrum for “personal communication services” (PCS) marked a sharp change in policy by the US Federal Communications Commission (FCC). Before turning to auctions the FCC had allocated valuable spectrum on the basis of comparative hearings (also known as “beauty contests”) and lotteries. Nobel laureate Ronald Coase long advocated that market-based mechanisms would improve the allocation of scarce spectrum resources, but his early insights were ignored for decades [1]. The PCS auction raised over six hundred million dollars for the US treasury and it was widely considered a success. Several authors discuss the advantages and disadvantages of auctions and beauty contests for allocating scarce spectrum [2, 3, 4]. For example, some argue that financially strong bidders might have advantages over weaker bidders in an auction, while others argue that with efficient capital markets such differences should be less of a concern. Nowadays, spectrum is predominantly assigned by auction, both in the US and elsewhere [5, 6], and in this paper we focus on questions of auction design.
The simultaneous multi-round auction (SMRA), which was designed for the US FCC in the early 90's has been the standard auction format for selling spectrum world wide for many years. It auctions multiple licenses for sale in parallel and uses simple activity rules which forces bidders to be active from the start. Despite the simplicity of its rules there can be considerable strategic complexity in the SMRA when there are synergies between licenses that cover adjacent geographic regions or between licenses in different frequency bands. Bidders who compete aggressively for a certain combination of licenses risk being exposed when they end up winning an inferior subset at high prices. When bidders rationally anticipate this exposure problem, competition will be suppressed with adverse consequences for the auction's performance. The exposure problem has led auction designers to consider combinatorial auctions, which enable bidders to express their preferences for an entire set of licenses directly. In fact, the design of spectrum auctions is seen as a pivotal problem im multi-object auction design and successful solutions are a likely role-model for other public or private sector auctions such as transportation or industrial procurement.
Since 2008, the combinatorial clock auction (CCA) has been used by regulators in various countries such as the Austria, Australia, Canada, Denmark, Ireland, the Netherlands, and Switzerland to sell spectrum.
The applicability of volcanic ash deposits on Vatnajökull ice cap, Iceland, as a time reference marker for measuring accumulation by the analysis of time sequential SAR backscatter data was investigated. A volcanic eruption at Grímsvötn caldera, a subglacial volcanic system beneath Vatnajökull, deposited an ash layer north of the vent in early November 2004. This ash layer covered a V-shaped area of ∽88km2 on the glacier surface. The ash fall, which was subsequently buried by snow, reveals a distinct backscatter signal in SAR images. In total, the σ0 backscatter values of 40 ENVISAT-ASAR images were analyzed, covering two post-eruption accumulation periods (4 November 2004 to 31 March 2005 and 25 October 2006 to 14 March 2006). Significant differences over time were observed in the SAR backscatter signals over the deposited ash, which appear to be related to the snow accumulation history. The backscatter signals were compared to meteorological conditions at the time of SAR acquisition and to accumulation data derived from two snow pits, one located within the ash fall. A linear regression analysis between the accumulation data and the SAR backscattering coefficient results in high R2 confidence values (>0.8), indicating that the SAR data can be used for estimating the areal accumulation distribution in areas with an existing ash layer.
Multibeam bathymetry and 3.5-kHz sub-bottom profiler data collected from the US icebreaker Healy in 2003 provide convincing evidence for grounded ice on the Chukchi Borderland off the northern Alaskan margin, Arctic Ocean. The data show parallel, glacially induced seafloor scours, or grooves, and intervening ridges that reach widths of 1000 m (rim to rim) and as much as 40 m relief. Following previous authors, we refer to these features as “megascale glacial lineations (MSGLs).” Additional support for ice grounding is apparent from stratigraphic unconformities, interpreted to have been caused by ice-induced erosion. Most likely, the observed sea-floor features represent evidence for massive ice-shelf grounding. The general ESE/WNW direction of the MSGLs, together with sediment, evidently bulldozed off the Chukchi Plateau, that is mapped on the western (Siberian) side of the plateau, suggests ice flow from the Canada Basin side of Chukchi Borderland. Two separate generations of glacially derived MSGLs are identified on the Chukchi Borderland from the Healy geophysical data. The deepest and oldest extensive MSGLs appear to be draped by sediments less than 5 m thick, whereas no sediment drape can be distinguished within the resolution of the sub-bottom profiles on the younger generation.
Initial infection with the sentinel respiratory pathogen in children with cystic fibrosis (CF), Pseudomonas aeruginosa (Pa), is generally with environmental strains of this ubiquitous organism. The purpose of this study was to evaluate the associations between meteorological and geographical factors and risk of initial Pa acquisition in young children with CF. Using the U.S. Cystic Fibrosis Foundation Patient Registry from 2003 to 2009, 3463 patients met inclusion criteria, of which 48% (n = 1659) acquired Pa during follow-up. From multivariable Weibull regression, increased risk of Pa acquisition was associated with increasing temperature [hazard ratio (HR) per 1 °C: 1·13; 95% confidence interval (CI) 1·08–1·13], dew point (HR per 1 °C: 1·10, 95% CI 1·07–1·13), rainfall (HR per cm: 1·10, 95% CI 1·07–1·12), latitude (HR per 1 °C northing: 1·15, 95% CI 1·11–1·20), longitude (HR per 1 °C easting: 1·01, 95% CI 1·01–1·02) and elevation (HR per 100 m: 1·05, 95% CI 1·03–1·07). These results suggest that environmental factors may play a previously unrecognized role in the aetiology of initial Pa acquisition.