567 research outputs found
Non-parametric Cosmology with Cosmic Shear
We present a method to measure the growth of structure and the background
geometry of the Universe -- with no a priori assumption about the underlying
cosmological model. Using Canada-France-Hawaii Lensing Survey (CFHTLenS) shear
data we simultaneously reconstruct the lensing amplitude, the linear intrinsic
alignment amplitude, the redshift evolving matter power spectrum, P(k,z), and
the co-moving distance, r(z). We find that lensing predominately constrains a
single global power spectrum amplitude and several co-moving distance bins. Our
approach can localise precise scales and redshifts where Lambda-Cold Dark
Matter (LCDM) fails -- if any. We find that below z = 0.4, the measured
co-moving distance r (z) is higher than that expected from the Planck LCDM
cosmology by ~1.5 sigma, while at higher redshifts, our reconstruction is fully
consistent. To validate our reconstruction, we compare LCDM parameter
constraints from the standard cosmic shear likelihood analysis to those found
by fitting to the non-parametric information and we find good agreement.Comment: 13 pages. Matches PRD accepted versio
An ideal of personal growth implied in the psychology of Jung and the metaphsics of Whitehead
Thesis (M.A.)--Boston University, 1936. This item was digitized by the Internet Archive
Whitehead's metaphysical interpretation of the meaning and growth of a human individual
Thesis (Ph.D.)--Boston UniversityThe problem of this dissertation is to discover what metaphysical meaning, if any, Whitehead ascribes to the growth of personality as a revelation of the objective truth and value of a human individual. Since Whitehead does not deal systematically with this problem, the present writer must introduce categories of self-knowledge that exemplify the generic principles of his metaphysics in order to interpret his relavent insights. Accordingly, the pertinent passages from his writings are correlated and interpreted in terms of a coherent account of the sense and value content, the purposive activity, and the rational validity which human though and conduct involve. For the full meaning of a human individual cannot be understood apart from a casual explanation of his given experience in accordance with a rational criterion of metaphysical truth
Calibrating mars orbiter laser altimeter pulse widths at mars science laboratory candidate landing sites
Accurate estimates of surface roughness allow quantitative comparisons between planetary terrains. These comparisons enable us to improve our understanding of commonly occurring surface processes, and develop a more complete analysis of candidate landing and roving sites. A (secondary) science goal of the Mars Orbiter Laser Altimeter was to map surface roughness within the laser footprint using the backscatter pulse-widths of individual pulses, at finer scales than can be derived from the elevation profiles. On arrival at the surface, these pulses are thought to have diverged to between 70 and 170 m, corresponding to surface roughness estimates at 35 and 70 m baselines respectively; however, the true baseline and relationship remains unknown. This work compares the Mars Orbiter Laser Altimeter pulse-widths to surface roughness estimates at various baselines from high-resolution digital terrain models at the final four candidate landing sites of Mars Science Laboratory. The objective was to determine the true baseline at which surface roughness can be estimated, and the relationship between surface roughness and the pulse-widths, to improve the reliability of current global surface roughness estimates from pulse-width maps. The results seem to indicate that pulse-widths from individual shots are an unreliable indicator of surface roughness, and instead, the pulse-widths should be downsampled to indicate regional roughness, with the Slope-Corrected pulse-width dataset performing best. Where Rough Patches are spatially large compared to the footprint of the pulse, pulse-widths can be used as an indicator of surface roughness at baselines of 150 to 300 m; where these patches are spatially small, as observed at Mawrth Vallis, pulse-widths show no correlation to surface roughness. This suggests that a more complex relationship exists, with varying correlations observed, which appear dependent on the distribution of roughness across the sites
Anterior Cruciate Ligament Reconstruction Surgery: Creating a Permissive Healing Phenotype in Military Personnel and Civilians for Faster Recovery
Introduction: Anterior cruciate ligament (ACL) rupture in military personnel and civilians can be a devastating injury. A service member is 10 times more likely to suffer an ACL injury than their civilian counterparts, and despite successful surgical stabilization, 4%-35% will develop arthrofibrosis, over 50% will not return to full active duty, and up to 50% will develop post-traumatic osteoarthritis (PTOA) within 15 years. Equally concerning, woman are 2 to 8 times more likely to experience ACL injuries than men, which represents a major knowledge gap.
Materials and Methods: A comprehensive literature search was performed in December 2021 using structured search terms related to prevalence, risk factors, disease progression, and treatment of ACL injury and reconstruction. The literature search was conducted independently by two researchers using PubMed, Cochrane, and Embase databases, with inclusion of articles with military, civilian, and sex relevance, and exclusion of most papers with a publication date greater than 10 years. The resources used for the review reflect the most current data, knowledge, and recommendations associated with research and clinical findings from reliable international sources.
Results: Currently, there is no effective system-based drug therapy that creates a âpermissive environmentâ to reduce synovial and cartilage stress after ACL injury and reconstruction and prevent secondary complications. We argue that progress in this area has been hampered by researchers and clinicians failing to recognize that (1) an ACL injury is a systemâs failure that affects the whole joint, (2) the early molecular events define and perpetuate different injury phenotypes, (3) male and female responses may be different and have a molecular basis, (4) the female phenotype continues to be under-represented in basic and clinical research, and (5) the variable outcomes may be perpetuated by the trauma of surgery itself. The early molecular events after ACL injury are characterized by an overexpression of joint inflammation, immune dysfunction, and trauma-induced synovial stress. We are developing an upstream adenosine, lidocaine, and magnesium therapy to blunt these early molecular events and expedite healing with less arthrofibrosis and early PTOA
complications.
Conclusions: ACL injuries continue to be a major concern among military personnel and civilians and represent a significant loss in command readiness and quality of life. The lack of predictability in outcomes after ACL repair or reconstruction underscores the need for new joint protection therapies. The maleâfemale disparity requires urgent investigation
In vivo arthroscopic temperatures: a comparison between 2 types of radiofrequency ablation systems in arthroscopic anterior cruciate ligament reconstructionâa randomized controlled trial
Purpose: To compare a plasma ablation device with a standard ablation device in anterior cruciate ligament (ACL) reconstruction to determine which system is superior in terms of intra-articular heat generation and diathermy efficiency.
Methods: This was a prospective, randomized controlled trial. The inclusion criteria were adult patients undergoing primary ACL reconstruction. Patients were randomized preoperatively to the standard ablation group or the plasma ablation group. A thermometer was inserted into the inferior suprapatellar pouch, and the temperature, time, and duration of radiofrequency ablation were measured continually.
Results: No significant differences were found between the standard ablation system and the plasma ablation system for maximum temperature (29.77°C and 29.34°C, respectively; P =.95), mean temperature (26.16°C and 26.99°C, respectively; P =.44), minimum temperature (22.66°C and 23.94°C, respectively; P =.54), and baseline temperature (26.80°C and 27.93°C, respectively; P =.35). Similarly, no significant differences were found for operative time (82.90 minutes and 80.50 minutes, respectively; P =.72) and mean diathermy activation times (2.6 minutes for both systems; P =.90). The between-system coefficient of variation for the measured parameters ranged from 0.12% to 3.69%. No intra-articular readings above the temperature likely to damage chondrocytes were recorded. The mean irrigation fluid temperature had a significant correlation with the maximum temperature reached during the procedure (Spearman rank correlation, r = 0.87; P < .01).
Conclusions: No difference in temperature was observed between the standard ablation and plasma ablation probes during ACL reconstruction. Temperatures did not exceed critical temperatures associated with chondrocyte death. Level of Evidence Level I, randomized controlled trial
Preparing for the Cosmic Shear Data Flood: Optimal Data Extraction and Simulation Requirements for Stage IV Dark Energy Experiments
Upcoming photometric lensing surveys will considerably tighten constraints on
the neutrino mass and the dark energy equation of state. Nevertheless it
remains an open question of how to optimally extract the information and how
well the matter power spectrum must be known to obtain unbiased cosmological
parameter estimates. By performing a Principal Component Analysis (PCA), we
quantify the sensitivity of 3D cosmic shear and tomography with different
binning strategies to different regions of the lensing kernel and matter power
spectrum, and hence the background geometry and growth of structure in the
Universe. We find that a large number of equally spaced tomographic bins in
redshift can extract nearly all the cosmological information without the
additional computational expense of 3D cosmic shear. Meanwhile a large fraction
of the information comes from small poorly understood scales in the matter
power spectrum, that can lead to biases on measurements of cosmological
parameters. In light of this, we define and compute a cosmology-independent
measure of the bias due to imperfect knowledge of the power spectrum. For a
Euclid-like survey, we find that the power spectrum must be known to an
accuracy of less than 1% on scales with k = 7 h /Mpc This requirement is not
absolute since the bias depends on the magnitude of modelling errors, where
they occur in k-z space, and the correlation between them, all of which are
specific to any particular model. We therefore compute the bias in several of
the most likely modelling scenarios and introduce a general formalism and
public code, RequiSim, to compute the expected bias from any non-linear model.Comment: 17 pages, 13 figures. Accepted and published in PR
Don't be so hard on yourself! Changes in self-compassion during the first year of university are associated with changes in well-being
Introduction Well-being declines during the first year of university. We examined if change in self-compassion was indirectly related to change in well-being through change in psychological need satisfaction during the first year of university. Methods First year university students (N=189, 77.2% female) completed self-report questionnaires at the beginning of the first semester and approximately five months later. Path analysis and bootstrapping procedures were used to examine residualized change scores. Results Change in self-compassion was positively related to (ps<0.05) change in psychological need satisfaction (β=0.49) and negatively related to change in negative affect (β=−0.24). Change in psychological need satisfaction was positively associated (ps<0.05) with change in vitality (β=0.58) and change in positive affect (β=0.52) and negatively associated with change in negative affect (β=−0.29). Change in self-compassion was indirectly related to change in vitality (b=0.56, 95% bootstrapped bias corrected confidence interval (BcCI)[0.38, 0.77]), positive affect (b=0.41, 95%BcCI [0.27, 0.58]), and negative affect (b=−0.26, 95%BcCI[−0.41, −0.13]) through change in psychological need satisfaction. Conclusions During the first year of university, change in self-compassion was associated with change in well-being because self-compassion enhanced psychological need satisfaction. Results highlight the potential of enhancing self-compassion during first year university to help mitigate student declines in well-being
Adenosine, Lidocaine and Magnesium (ALM) therapy modulates early sex-specific inflammatory and immune responses following experimental anterior cruciate ligament rupture and reconstruction
Background: Early dysregulation of local and systemic inflammatory and immune responses is implicated in the pathogenesis of fibrotic and degenerative complications after anterior cruciate ligament reconstruction (ACLR) surgery. In other surgical trauma models, ALM therapy has been shown to blunt inflammation, leading to a more permissive healing environment in injured tissues. The purpose of this study was to evaluate sex-specific effects of surgery and perioperative ALM therapy on leukocyte mobilization and activation, and systemic and joint tissue inflammation in a rat model of ACL rupture and reconstruction.
Methods: Adult male and female SpragueâDawley rats were randomly divided into ALM (male, n = 15; female, n = 14) or Saline control (male, n = 13; female, n = 14) treatment groups. Three days after non-invasive ACL rupture, ACLR surgery was performed on the injured knee. Animals received a 1 h perioperative IV ALM or saline drip, and a 0.1 ml IA bolus of ALM or saline, and were monitored to 120 h postoperative. Hematology, leukocyte immunophenotyping, plasma and synovial inflammatory mediator concentrations, and joint tissue histopathology and gene expression of inflammatory markers were assessed.
Results: Following ACLR surgery, plasma concentrations of inflammatory cytokines IL-6, TNF-α and IL-1ÎČ peaked later and at a higher magnitude in females compared to males, with ALM dampening this systemic inflammatory response. At 1 h postoperative, ALM boosted circulating B cell numbers in males and females, and decreased neutrophil activation in females. By 72 h, numbers of circulating T cells with immunoregulatory potential were increased in all ALM-treated animals compared to Saline controls, and corresponded to a significant reduction in synovial TNF-α concentrations within the operated knees. Sex-specific treatment differences were found in inflammatory and immune profiles in the synovial fluid and joint tissues. Inflammatory cell infiltration and gene expression of markers of inflammation (NfÎșb, Nlrp3), cytoprotective responses (Nrf2), and angiogenesis (Vegf ) were increased in joint synovial tissue from ALM-treated males, compared to controls. In females, ALM treatment was associated with increased mononuclear cell recruitment, and expression of M2 macrophage marker (Arg1) in joint synovial tissue
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