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ObjectiveTo evaluate the psychological implications of cardiovascular preparticipation screening (PPS) in athletes.DesignSystematic review.Data sourcesMEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, APA PsycInfo, Cochrane Library and grey literature sources.Study eligibility criteriaObservational and experimental studies assessing a population of athletes who participated in a cardiovascular PPS protocol, where psychological outcomes before, during and/or after PPS were reported.MethodsResults of included studies were synthesised by consolidating similar study-reported measures for key psychological outcomes before, during and/or after screening. Summary measures (medians, ranges) were computed across studies for each psychological outcome.ResultsA total of eight studies were included in this review (median sample size: 479). Study cohorts consisted of high school, collegiate, professional and recreational athletes (medians: 59% male, 20.5 years). Most athletes reported positive reactions to screening and would recommend it to others (range 88%–100%, five studies). Increased psychological distress was mainly reported among athletes detected with pathological cardiac conditions and true-positive screening results. In comparison, athletes with false-positive screening results still reported an increased feeling of safety while participating in sport and were satisfied with PPS. A universal conclusion across all studies was that most athletes did not experience psychological distress before, during or after PPS, regardless of the screening modality used or accuracy of results.ConclusionPsychological distress associated with PPS in athletes is rare and limited to athletes with true-positive findings. To mitigate downstream consequences in athletes who experience psychological distress, appropriate interventions and resources should be accessible prior to the screening procedure.PROSPERO registration numberCRD42021272887.

Environmental impact assessment (EIA) is a central procedure that governments use to evaluate the merits and risks of natural resource management decisions and is often labeled red tape. Increasingly, decisionmakers from across the political spectrum are exempting EIA in order to expedite implementation of necessary actions for climate resilience and clean energy. Yet few studies have quantified the extent that EIA is the main barrier to efficient implementation of government priorities. We gather administrative data from the US Forest Service (USFS) on more than 4,500 silviculture, fuels, and invasive species management actions initiated 2009–2021 and use survival analysis to compare the time it takes agency offices to comply with the 1970 National Environmental Policy Act (NEPA) relative to other implementation tasks. Results indicate that for most actions the USFS takes as long or longer to award first contracts and rollout first on-the-ground activities than to complete NEPA processes, and that the NEPA process accounts for one-fifth of planned implementation time. Results call attention toward efficiency barriers that slow implementation after EIA and away from exemption strategies that deliver short-term political benefits at the expense of public trust and sound decision-making under a shifting climate.

Alpha-synuclein pathology is associated with dopaminergic neuronal loss in the substantia nigra (SN) of Parkinson's patients. Working across human and mouse models, we investigated mechanisms by which the accumulation of soluble α-synuclein oligomers leads to neurodegeneration. Biochemical analysis of the midbrain of α-synuclein overexpressing BAC-transgenic male and female mice revealed age- and region-dependent mitochondrial dysfunction and accumulation of damaged proteins downstream of the RE1 Silencing Transcription Factor (REST). Vulnerable SN dopaminergic neurons displayed low REST levels compared with neighboring protected SN GABAergic neurons, which correlated with the accumulation of α-synuclein oligomers and disrupted mitochondrial morphology. Consistent with a protective role, REST levels were reduced in patient induced pluripotent stem cell-derived dopaminergic neurons carrying theSNCA-Triplicationmutation, which accumulated α-synuclein oligomers and mitochondrial damage, and displayed REST target gene dysregulation. Furthermore, CRISPR-mediated REST KO induced mitochondrial dysfunction and impaired mitophagyin vitro. Conversely, REST overexpression attenuated mitochondrial toxicity and mitochondrial morphology disruption through the transcription factor PGC-1α. Finally, decreased α-synuclein oligomer accumulation and mitochondrial dysfunction in mice correlated with nuclear REST and PGC-1α in protected SN GABAergic neurons compared with vulnerable dopaminergic neurons. Our findings show that increased levels of α-synuclein oligomers cause dopaminergic neuronal-specific dysfunction through mitochondrial toxicity, which can be attenuated by REST in an early model of Parkinsonian pathology. These findings highlight REST as a mediator of dopaminergic vulnerability in PD.SIGNIFICANCE STATEMENTUnderstanding early Parkinsonian pathophysiology through studies of advanced preclinical models is fundamental to the translation of disease-modifying therapies. Here we show disease-relevant levels of α-synuclein expression in mice leads to accumulation of α-synuclein oligomers in the absence of overt aggregation, and mitochondrial dysfunction in dopaminergic neurons lacking the RE1 Silencing Transcription Factor. Our findings identify the mechanism of action of RE1 Silencing Transcription Factor and PGC-1α as mediators of dopaminergic vulnerability in α-synuclein BAC-transgenic mice and induced pluripotent stem cell-derived dopaminergic cultures, highlighting their potential as therapeutic targets.

Intimate partner violence (IPV) is serious social concern and is often perpetrated by police officers. Research suggests that 20–40% of police families experience IPV. The purpose of this study is ...

External dose rates were measured 1 m away from 230 Lu-177 patients to characterise the variability in normalised dose rates as a function of administered activity, body mass index (BMI) and sex. The largest dose rate observed was 0.07 mSv/h associated with an administered activity of 7.2 GBq. Substantial variability was found in the distribution of the normalised dose rate associated that had an average of 0.0037 mSv/h per GBq and a 95% confidence interval of 0.0024–0.0058 mSv/h per GBq. Based on this study, estimating the patient dose rate based on the Lu-177 gamma exposure factor overestimates the dose rate by a factor of 2. A statistically significant inverse relationship was found between the patient dose rate and patient BMI and an empirically derived equation relating these two quantities was reported. On average, male patient dose rates were 3.5% lower than female dose rates, which may be attributed to the larger average BMI of the male patient group.

A common pathological hallmark of amyotrophic lateral sclerosis (ALS) and the related neurodegenerative disorder frontotemporal dementia, is the cellular mislocalization of transactive response DNA-binding protein 43 kDa (TDP-43). Additionally, multiple mutations in the TARDBP gene (encoding TDP-43) are associated with familial forms of ALS. While the exact role for TDP-43 in the onset and progression of ALS remains unclear, the identification of factors that can prevent aberrant TDP-43 localization and function could be clinically beneficial. Previously, we discovered that the oxidation resistance 1 (Oxr1) protein could alleviate cellular mislocalization phenotypes associated with TDP-43 mutations, and that over-expression of Oxr1 was able to delay neuromuscular abnormalities in the hSOD1G93A ALS mouse model. Here, to determine whether Oxr1 can protect against TDP-43-associated phenotypes in vitro and in vivo, we used the same genetic approach in a newly described transgenic mouse expressing the human TDP-43 locus harbouring an ALS disease mutation (TDP-43M337V). We show in primary motor neurons from TDP-43M337V mice that genetically-driven Oxr1 over-expression significantly alleviates cytoplasmic mislocalization of mutant TDP-43. We also further quantified newly-identified, late-onset neuromuscular phenotypes of this mutant line, and demonstrate that neuronal Oxr1 over-expression causes a significant reduction in muscle denervation and neuromuscular junction degeneration in homozygous mutants in parallel with improved motor function and a reduction in neuroinflammation. Together these data support the application of Oxr1 as a viable and safe modifier of TDP-43-associated ALS phenotypes.

Assessment of remote sensing derived freeze/thaw products from L-band radiometry requires ground validation. There is growing interest in utilizing soil moisture networks to meet this validation re...

Several large in-situ soil moisture-monitoring networks currently exist over seasonally frozen regions that may have use for the validation of remote sensing soil freeze/thaw (F/T) products. However, further understanding of how the existing network instrumentation responds to changes in near surface soil F/T is recommended. This case study describes the results of a small plot-scale (7 × 7 m) study from November 2013 through April 2014 instrumented with 36 impedance probes. Soil temperature and real dielectric permittivity ϵr' were measured every 15 minutes during F/T transition periods at shallow soil depths (0–10 cm). Categorical soil temperature and real dielectric permittivity techniques were used to define the soil F/T state during these periods. Results demonstrate that both methods for detecting soil F/T have strong agreement (84.7–95.6%) during the fall freeze but weak agreement (53.3–60.9%) during the spring thaw. Bootstrapping results demonstrated both techniques showed a mean difference within ±1.0°C and ±1.4 ϵr' between the standard 5 cm below surface measurement depth and probes at 2, 10 and integrated 0–5.7 cm depths installed within the same study plot. Overall this study demonstrates that the Hydra Probe offers promise for near surface soil F/T detection using existing soil moisture monitoring networks particularly for the fall freeze.

Land surface freeze/thaw (F/T) dynamics impact the surface energy balance, carbon fluxes, and hydrologic processes. Recent and on-going L-Band (≈ 1.4 GHz) spaceborne missions have the potential to provide enhanced information on F/T state over large geographic regions with rapid revisit time. However, the low spatial resolution of these spaceborne observations (≈ 45 km) makes it difficult to isolate the primary contributions to the F/T signal, including the soil, snow, and vegetation states. A ground-based L-Band radiometer measurement campaign was conducted in Saskatchewan, Canada during the winter of 2014–2015 to evaluate brightness temperature sensitivity to F/T processes, snow, liquid water in snow and assess theoretical retrievals of soil permittivity (eG), and snow density from experimental data. The ground-based radiometer was run in multiple configurations. First, temporally continuous measurements were conducted through the winter over an agricultural field, with a comprehensive network of reference snow and soil observations characterizing the F/T state of the soils within or adjacent to the radiometer footprint. Secondly, weekly multi-angular L-Band measurements were made at an undisturbed site of naturally accumulating snow cover, over a site that was kept snow free, and a site with artificially compacted snow. Results from the assessment of the land surface F/T retrieval algorithm showed that L-Band measurements are sensitive to the near surface F/T state of the soil, with the highest level of agreement found between the near surface (2.5 cm) F/T reference measurements of soil temperature and eG (accuracies of 91.1% and 92.9%, respectively). Several mid-winter melt events with air temperatures (Tair) above 0°, and soil temperatures below 0 °C, illustrated that liquid water within the snow dramatically increase the TB, resulting in false retrievals of soil thaw events using existing L-Band F/T retrieval algorithms. However, Tair was also shown to have a high commission errors compared to radiometer observations in detecting snow melt, because of the delay between Tair > 0 °C and the onset of melt resulting in a measurable wet snow signal at L-Band. The retrieval of snow density (ρs), of the bottom 10 cm of the snowpack tended to underestimate high ρs (> 400 kg m− 3), and agreed well for lower ρs (

Wireless systems employing frequency-division duplexing (FDD) must use duplexing filters to isolate the sensitive receiver from its own strong transmission. The number of filters in the duplexer is equal to the total number of aggregated transmit and receive bands. These filters are nontunable; therefore, a separate duplexer is required for each combination of operating bands. This paper presents an adaptive duplexer architecture capable of handling more than one receiver channel and tunable over a wide frequency range. The structure uses a combination of a low-isolation device with multiple analog canceling loops controlled by a normalized least mean squares (N-LMS) algorithm to track changes in signal leakage. The control is a multiple-input–multiple-output (MIMO) problem. This paper shows that modeling the inverse plant can orthogonalize the problem and dramatically improve convergence times with reduced complexity over previous search algorithms. Low-power pseudonoise (PN) pilot signals are proposed to detect and cancel the transmitter noise. Simulations show that 50 dB of isolation is possible with 20-MHz Long-Term Evolution (LTE)-like channels. Convergence takes 80 iterations (10 ms) from cold or 15 iterations (1.5 ms) for changes in carrier frequency or antenna loading.

In this paper, we discuss an efficient divide-and-conquer algorithm for the negative cost girth (NCG) problem in planar networks. Recall that the girth of an unweighted graph (directed or undirected) is the length of the shortest cycle in the graph. We extend the notion of girth to arbitrarily weighted networks as follows: The negative cost girth of a graph is the number of edges in a shortest negative cost simple cycle, i.e., a negative cost cycle having the fewest number of edges. The NCG problem in general networks has been well-studied, and there exist several algorithms for this problem. Clearly, the extant algorithms for the NCG problem can be used when the input network is restricted to be planar. However, the techniques used in this paper result in an algorithm with a superior running time. Our algorithm is based on the well-known Lipton-Tarjan planar separator theorem. On a directed, weighted, planar network G = { V , E , c } with n vertices, m = O ( n ) edges, and negative cost girth k, the algorithm runs in O ( n 1.5 ? k ) time. This is a significant improvement over the O ( m ? n ? k ) = O ( n 2 ? k ) running time that results, when the fastest known topology-oblivious algorithm for the NCG problem is restricted to planar networks. Additionally, our algorithm can be extended to find the NCG in selected generalizations of planar networks.

The undirected negative cost cycle detection (UNCCD) problem is concerned with checking whether an undirected, weighted graph contains a negative cost cycle. Known approaches for solving this problem involve reducing it to either the minimum weight$$b$$b-matching problem or the minimum weight$$T$$T-join problem. In this paper, we formally describe these two approaches and provide the tightest known analysis of the $$b$$b-matching approach. Our analysis establishes that the $$b$$b-matching approach runs in $$O((n+m)^{2}\cdot \log (n+m))$$O((n+m)2·log(n+m)) time on a graph with $$n$$n nodes and $$m$$m edges. We also explore the case where the edge costs are integers in the range $$\{-K,\ldots , K\}$${-K,?,K}. For $$K = O(1)$$K=O(1), we provide improved time bounds for both the above-mentioned approaches by exploiting the existence of specialized procedures for optimization problems in graphs with integral positive edge costs. We show that while the $$T$$T-join algorithm has a better time bound for general graphs, the $$b$$b-matching algorithm is more efficient for sparse graphs. Finally, we present one of the first, extensive empirical studies for the UNCCD problem. We examine both approaches on several different families of undirected graphs. Our findings provide insight into the actual efficiency of each approach and reinforce the asymptotic analysis of our algorithms.

This paper proposes a new algorithm for the minimum spanning tree verification (MSTV) problem in undirected graphs. The MSTV problem is distinct from the minimum spanning tree construction problem. The above problems have been studied extensively, and there exist several papers in the literature devoted to them. Our algorithm for the MSTV problem combines the insights of Bor?vka's algorithm for constructing a minimum spanning tree with a bucketing scheme. The principal idea underlying this combination is the efficient identification of edges that cannot be part of any minimum spanning tree. Although the proposed algorithm imposes no restrictions on the input graph, it was designed to exploit the case in which the number of distinct edge weights is small. On a graph with $$n$$n vertices, $$m$$m edges, and $$K$$K distinct edge weights, our algorithm runs in $$O(m+n\cdot K)$$O(m+n·K) time. It follows that our algorithm runs in linear time if $$K$$K is a fixed constant. Although there exist several linear time MSTV algorithms in the literature, our algorithm improves on the state of the art in two ways, viz., it is conceptually simpler, and it is easy to implement. We contrast the performance of our algorithm vis-a-vis Hagerup's linear time MSTV algorithm, which is one of the more practical linear-time MSTV algorithms. Our experiments indicate that the proposed algorithm is superior to Hagerup's algorithm when $$K \le 24$$K≤24. One surprising observation is that our algorithm is substantially faster than Hagerup's algorithm on "No" instances, i.e., on instances in which the input spanning tree is not the minimum spanning tree.

This paper discusses the implementation of a new parallel algorithm for the negative cost girth (NCG) problem. The girth of an unweighted graph (directed or undirected) is defined as the length of the shortest cycle in the graph. We extend the notion of girth to networks with arbitrary weights in the following way: The negative cost girth of a network is the number of edges of the shortest negative cost cycle (i.e., the negative cost cycle with the fewest number of edges). The NCG problem has been well-studied, and there exist several polynomial time algorithms for the same. This problem finds applications in several domains, including constraint-solving, real-time scheduling, and program verification. In this paper, our focus is on a parallel implementation for solving the NCG problem that runs in $$O(\log k \cdot \log n)$$ O ( log k · log n ) parallel time using $$O(n^3)$$ O ( n 3 ) processors, where $$n$$ n is the number of vertices, and $$k$$ k is the NCG. We conduct an empirical analysis for both the parallel implementation, using MPI, and the corresponding sequential NCG implementation. Our experiments indicate that as the number of processors doubles, the total execution time reduces by approximately one-half.

Effective literature searching for research. Sarah Gash Only connect: shaping networks and knowledge for the new millennium. Trevor Haywood Information sources for the press and broadcast media. Sarah Adair (ed.). Exploring the contexts of information behaviour. Thornas D. WiIson and David K. Allen. Researching markets by industry sectors: a guide to sources and services. David Mort (ed.). Change management for information services. Sharon Penfold. LISU Reports - NHS libraries: statistics 1997-98. Public library materials fund and budget survey 1998-2000.Perspectives of public library use 2: a compendium of survey information.

This paper is concerned with the design and analysis of improved algorithms for determining the optimal length resolution refutation (OLRR) of a system of difference constraints over an integral domain. The problem of finding short explanations for unsatisfiable Difference Constraint Systems (DCS) finds applications in a number of design domains including program verification, proof theory, real-time scheduling, and operations research. These explanations have also been called “certificates” and “refutations” in the literature. This problem was first studied in Subramani (J Autom Reason 43(2):121–137, 2009 ), wherein the first polynomial time algorithm was proposed. In this paper, we propose two new strongly polynomial algorithms which improve on the existing time bound. Our first algorithm, which we call the edge progression approach, runs in O ( n 2 · k + m · n · k ) time, while our second algorithm, which we call the edge relaxation approach, runs in O ( m · n · k ) time, where m is the number of constraints in the DCS, n is the number of program variables, and k denotes the length of the shortest refutation. We conducted an extensive empirical analysis of the three OLRR algorithms discussed in this paper. Our experiments indicate that in the case of sparse graphs, the new algorithms discussed in this paper are superior to the algorithm in Subramani (J Autom Reason 43(2):121–137, 2009 ). Likewise, in the case of dense graphs, the approach in Subramani (J Autom Reason 43(2):121–137, 2009 ) is superior to the algorithms described in this paper. One surprising observation is the superiority of the edge relaxation algorithm over the edge progression algorithm in all cases, although both algorithms have the same asymptotic time complexity.

The Shoshan-Zwick algorithm solves the all pairs shortest paths problem in undirected graphs with integer edge costs in the range $\{1, 2, \dots, M\}$. It runs in $\tilde{O}(M\cdot n^{\omega})$ time, where $n$ is the number of vertices, $M$ is the largest integer edge cost, and $\omega < 2.3727$ is the exponent of matrix multiplication. It is the fastest known algorithm for this problem. This paper points out the erroneous behavior of the Shoshan-Zwick algorithm and revises the algorithm to resolve the issues that cause this behavior. Moreover, it discusses implementation aspects of the Shoshan-Zwick algorithm using currently-existing sub-cubic matrix multiplication algorithms., Comment: 16 pages

Assesses the role of public libraries with particular reference to the services they provide to socially excluded groups in society and drawing on the works of John Stuart Mill and Jurgen Habermas. Discusses the way in which Mill’s reworking of utilitarianism and the emergence of Habermas’ concept of the ‘public sphere’ influenced the formation and development of the public library and the definition of its role in terms of social inclusion and exclusion. One of the major strengths within the public sphere of the recreational role of the public library is seen to be its impartiality, something upon which Habermas laid great emphasis. Concludes that the major problem facing public libraries in the future is the very real danger that the redefinition of the educational and informational roles of the public library into a ‘faked version’ of the public sphere will lead to a diminution of service provision in its recreational and cultural roles.

AuthorBase, a working prototype database of authoring system software, was developed as part of a study of authoring software conducted by the National Library of Medicine. In this article, the authors discuss development issues ranging from the scope of the database to what information to document. The prototype demonstrates that records of reasonable integrity can be derived from vendor-supplied information. However, users should understand that the database is only a starting point in searching for authoring software and a resource for becoming generally familiar with the technology.

A study of authoring system technology was done to update a previous study done in 1985. While the earlier study focused on software selection methods, the current one emphasizes trends in authoring tool characteristics, vendor approaches to the market-place, and evaluation methods. It also raises questions about some of the often tacit assumptions underlying the technology's development and use.

THIS ARTICLE summarizes information about authoring system technology resulting from a recent review of eighty products. Alternative authoring approaches, such as programming languages, authoring languages, and authoring systems are described. Assumptions underlying authoring system development and use concerning productivity, course quality, and course development are examined. Selection procedures and criteria are suggested that are sensitive to the varied authoring needs of different contexts. Finally, trends in software development, evaluation, marketing, and use are presented.

In many applications, hosts in a peer to peer network may wish to maintain their anonymity or the privacy of their queries. In some applications, an even stronger guarantee is desirable: hosts would like to prevent others from determining whether they participate in the network at all. Darknets, or friend-to-friend networks, are one approach to preventing the discovery of hosts within a peer to peer network [1]. In such a network, hosts only form Internet connections with and directly communicate with a small set of hosts whose operators are known and trusted a priori. That is, each user only connects to her friends, trusting that her friends will not reveal her identity or existence in the network.

Steam Assisted Gravity Drainage (SAGD) and Expanding Solvent SAGD (ES-SAGD) have previously been compared and ES-SAGD has shown improved oil recovery with lower energy and water requirements and significant oil upgrading. However, solvent selection is the key factor which determines the performance of ES-SAGD due to the asphaltene-solvent interaction. The change in asphaltene stability with the solvent type can have several drawbacks during ES-SAGD. Stable emulsion formation is one of these problems which have not been investigated thoroughly for ES-SAGD. In this study, we characterized both water-in-oil and oil-in-water type of emulsions originating from SAGD, SAGD with n-hexane and SAGD with n-hexane and toluene mixture experiments. These three experiments were conducted on 8.65 °API Canadian bitumen with 34.3 wt% asphaltene content. Structural changes in produced oil, produced water, and spent rock samples were analyzed with Fourier Transform Infrared (FTIR) spectroscopy. Emulsions in produced oil and water samples were determined with microscopic images. The differences in emulsions were interpreted with the wettability change determined on spent rock samples. Moreover, the asphaltene fraction of produced oil samples is further analyzed with FTIR and zeta potential measurements. For produced oil, the greatest asphaltene content with more severe emulsion formations were detected on the sample originating from SAGD. In terms of stability, because the asphaltenes originating from both ES-SAGD experiments have higher zeta potential values, lower emulsion stability has been observed for the produced oil originating from ES-SAGD. In summary, the role of asphaltenes on emulsion formation has been studied for SAGD and ES-SAGD for bitumen extraction. ES-SAGD with asphaltene soluble solvents leads to the formation of less stable emulsions.