51 research outputs found
Ram-pressure stripping of a kicked Hill sphere:Prompt electromagnetic emission from the merger of stellar mass black holes in an AGN accretion disk
Accretion disks around supermassive black holes (SMBHs) are promising sites for stellar mass black hole (BH) mergers due to mass segregation and merger acceleration by disk gas torques. Here we show that a gravitational-wave (GW) kick at BH merger causes ram-pressure stripping of gas within the BH Hill sphere. If R_H ≥ H, the disk height, an off-center UV flare at a_(BH) ~ 10³ r_g, emerges within t_(UV) ~ O(2 days)(a_(BH)/10³ r_g)(M_(SMBH)/10⁸ M_⊙)(v_(kick)/10² km s⁻¹) postmerger and lasts O(R_H/v_(kick)) ~ O(5t_(UV)). The flare emerges with luminosity O(10⁴² erg s⁻¹(t_(UV)/2 days)⁻¹(M_(Hill)/1M_⊙)(v_(kick)/10² km s⁻¹)². Active galactic nucleus optical/UV photometry is altered and asymmetric broad emission line profiles can develop after weeks. If R_H 50M_⊙
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Paracrine effects of TLR4-polarised mesenchymal stromal cells are mediated by extracellular vesicles
Mesenchymal stromal cells (MSCs) are adult stem cells able to give rise to bone, cartilage and fat cells. In addition,
they possess immunomodulatory and immunosuppressive properties that are mainly mediated through secretion
of extracellular vesicles (EVs). In a previous issue of Journal of Translational Medicine, Ti and colleagues demonstrated
that preconditioning of MSCs with bacterial lipopolysaccharides results in secretion of EVs that can polarise mac‑
rophages towards anti-inflammatory M2 phenotype. Moreover, the authors suggest that EVs of lipopolysaccharide
(LPS)-treated MSCs are superior to EVs of untreated MSCs concerning their ability to support wound healing. Our
commentary critically discusses parallel efforts of other laboratories to generate conditioned media from stem cells
for therapeutic applications, and highlights impact and significance of the study of Ti et al. Finally, we summarise its
limitations and spotlight areas that need to be addressed to better define the underlying molecular mechanisms
Gender differences in first episode psychotic mania
Background : The aim of this paper was to delineate the impact of gender on premorbid history, onset, and 18 month outcomes of first episode psychotic mania (FEPM) patients. Methods : Medical file audit assessment of 118 (male = 71; female = 47) patients with FEPM aged 15 to 29 years was undertaken on clinical and functional measures. Results : Males with FEPM had increased likelihood of substance use (OR = 13.41, p < .001) and forensic issues (OR = 4.71, p = .008), whereas females were more likely to have history of sexual abuse trauma (OR = 7.12, p = .001). At service entry, males were more likely to be using substances, especially cannabis (OR = 2.15, p = .047), had more severe illness (OR = 1.72, p = .037), and poorer functioning (OR = 0.96, p = .045). During treatment males were more likely to decrease substance use (OR = 5.34, p = .008) and were more likely to be living with family (OR = 4.30, p = .009). There were no gender differences in age of onset, psychopathology or functioning at discharge. Conclusions : Clinically meaningful gender differences in FEPM were driven by risk factors possibly associated with poor outcome. For males, substance use might be associated with poorer clinical presentation and functioning. In females with FEPM, the impact of sexual trauma on illness course warrants further consideration
Psychobiomotor Assessment Of Football Playing Ability
Studied possible psychobiomotor predictors of successful performance among collegiate football players in the offensive backfield positions, using 19 male tryouts (aged 19–24 yrs) for halfback or fullback. Ss were assessed on the Sixteen Personality Factor Questionnaire (16PF), physiological variables, anaerobic capacity, perceptual-motor skills, and 15 constructs identified by coaches as important to the positions. Four variables emerged as predictors of football-playing ability: conservatism, pass-receiving ability, aggressiveness, and anaerobic capacity. Implications for training programs are discussed
Validation of an intrinsic groundwater pollution vulnerability methodology using a national nitrate database.
The importance of groundwater for potable supply, and the many sources of
anthropogenic contamination, has led to the development of intrinsic groundwater
vulnerability mapping. An Analysis of Co-Variance and Analysis of Variance are
used to validate the extensively applied UK methodology, based upon nitrate
concentrations from 1,108 boreholes throughout England and Wales. These largely
confirm the current aquifer and soil leaching potential classifications and
demonstrate the benefits of combining soil and low permeability drift
information. European legislation such as the Water Framework Directive will
require more dynamic assessments of pollutant risk to groundwater. These results
demonstrate that a number of improvements are required to future intrinsic
groundwater vulnerability methodologies. The vertical succession of geological
units must be included, so that non-aquifers can be zoned in the same way as
aquifers for water supply purposes, while at the same time recognising their
role in influencing the quality of groundwater in deeper aquifers.
Classifications within intrinsic vulnerability methodologies should be based
upon defined diagnostic properties rather than expert judgement. Finally the
incorporation into groundwater vulnerability methodologies of preferential flow
in relation to geological deposits, soil type and land management practices
represents a significant, but important, future challenge
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