290 research outputs found
Microvascular Anastomosis Under 3D Exoscope or Endoscope Magnification: A Proof-Of-Concept Study
Background: Extracranial-intracranial bypass is a challenging procedure that requires special microsurgical skills and an operative microscope. The exoscope is a tool for neurosurgical visualization that provides view on a heads-up display similar to an endoscope, but positioned external to the operating field, like a microscope. The authors carried out a proof-of-concept study evaluating the feasibility and effectiveness of performing microvascular bypass using various new exoscopic tools. Methods: We evaluated microsurgical procedures using a three-dimensional (3D) endoscope, hands-free robotic automated positioning two-dimensional (2D) exoscope, and an ocular-free 3D exoscope, including surgical gauze knot tying, surgical glove cutting, placental vessel anastomoses, and rat vessel anastomoses. Image quality, effectiveness, and feasibility of each technique were compared among different visualization tools and to a standard operative microscope. Results: 3D endoscopy produced relatively unsatisfactory resolution imaging. It was shown to be sufficient for knot tying and anastomosis of a placental artery, but was not suitable for anastomosis in rats. The 2D exoscope provided higher resolution imaging, but was not adequate for all maneuvers because of lack of depth perception. The 3D exoscope was shown to be functional to complete all maneuvers because of its depth perception and higher resolution. Conclusion: Depth perception and high resolution at highest magnification are required for microvascular bypass procedures. Execution of standard microanastomosis techniques was unsuccessful using 2D imaging modalities because of depth-perception-related constraints. Microvascular anastomosis is feasible under 3D exoscopic visualization; however, at highest magnification, the depth perception is inferior to that provided by a standard operative microscope, which impedes the procedure
Love and Truth: What Really Matters for Children Born Through Third‐Party Assisted Reproduction
Abstract: Ever since the birth of the first baby born through in vitro fertilization in 1978, advances in reproductive technologies have raised new concerns about the outcomes for children. In this article, I summarize research on children born through assisted reproduction involving a third party, that is, children born through egg donation, sperm donation, and surrogacy, with particular attention to the findings of a longitudinal study of children born to heterosexual couples in the United Kingdom. The assisted reproduction families generally showed high levels of family functioning and children's adjustment from early childhood through to adolescence, suggesting that biological relatedness is less important than positive parent–child relationships for the well‐being of children conceived by third‐party assisted reproduction. Similarly, studies of families created by third‐party reproduction with two mothers, single mothers, two fathers, and single fathers have shown that these families function well
Purpose of social networking use and victimisation: Are there any differences between university students and those not in HE?
Current literature widely reports successful uses of social media as a source of information, collaborative and learning tool for students in higher education. Although universities increasingly promote the use of Social Network Services (SNS) little is known about how students use them. Also the adverse effects of social media activity, such as cybercrime victimisation in HE, are under explored. Concerns over informal leisure use of SNS by students leading to cyber victimisation may help explain slow adoption of social media in education. This paper shows, however, that students use SNS in a similar way to those users who are not in education, with more that 60% using SNS for both socialising and gathering information. We find that students are less likely to be victims of cybercrime than non-students suggesting that SNS activity is less risky within the university lifespan. The implications of this study are significant for policy and practice for universities and educational authorities
Intrinsic efficiency limits in low-bandgap non-fullerene acceptor organic solar cells
In bulk heterojunction (BHJ) organic solar cells (OSCs) both the electron affinity (EA) and ionization energy (IE) offsets at the donor–acceptor interface should equally control exciton dissociation. Here, we demonstrate that in low-bandgap non-fullerene acceptor (NFA) BHJs ultrafast donor-to-acceptor energy transfer precedes hole transfer from the acceptor to the donor and thus renders the EA offset virtually unimportant. Moreover, sizeable bulk IE offsets of about 0.5 eV are needed for efficient charge transfer and high internal quantum efficiencies, since energy level bending at the donor–NFA interface caused by the acceptors’ quadrupole moments prevents efficient exciton-to-charge-transfer state conversion at low IE offsets. The same bending, however, is the origin of the barrier-less charge transfer state to free charge conversion. Our results provide a comprehensive picture of the photophysics of NFA-based blends, and show that sizeable bulk IE offsets are essential to design efficient BHJ OSCs based on low-bandgap NFAs
TIC 378898110: A Bright, Short-Period AM CVn Binary in TESS
AM CVn-type systems are ultracompact, helium-accreting binary systems which
are evolutionarily linked to the progenitors of thermonuclear supernovae and
are expected to be strong Galactic sources of gravitational waves detectable to
upcoming space-based interferometers. AM CVn binaries with orbital periods
20--23 min exist in a constant high state with a permanently ionised
accretion disc. We present the discovery of TIC 378898110, a bright (
mag), nearby ( pc), high-state AM CVn binary discovered in TESS
two-minute-cadence photometry. At optical wavelengths this is the
third-brightest AM CVn binary known. The photometry of the system shows a
23.07172(6) min periodicity, which is likely to be the `superhump' period and
implies an orbital period in the range 22--23 min. There is no detectable
spectroscopic variability. The system underwent an unusual, year-long
brightening event during which the dominant photometric period changed to a
shorter period (constrained to min), which we suggest may be
evidence for the onset of disc-edge eclipses. The estimated mass transfer rate,
, is
unusually high and may suggest a high-mass or thermally inflated donor. The
binary is detected as an X-ray source, with a flux of erg cm s in the 0.3--10 keV range. TIC 378898110
is the shortest-period binary system discovered with TESS, and its large
predicted gravitational-wave amplitude makes it a compelling verification
binary for future space-based gravitational wave detectors.Comment: 15 pages, 14 figures. Accepted to MNRA
Cytogenetic complexity in chronic lymphocytic leukemia: definitions, associations and clinical impact
Recent evidence suggests that complex karyotype (CK) defined by the presence of 653 chromosomal aberrations (structural and/or numerical) identified by chromosome banding analysis (CBA) may be relevant for treatment decision-making in chronic lymphocytic leukemia (CLL). However, many challenges towards routine clinical application of CBA remain. In a retrospective study of 5290 patients with available CBA data, we explored both clinicobiological associations and the clinical impact of CK in CLL. We found that patients with 655 abnormalities, defined as high-CK, exhibit uniformly dismal clinical outcome, independently of clinical stage, TP53 aberrations (deletion of chromosome 17p and or TP53 mutations, TP53abs) and the expression of somatically hypermutated (M-CLL) or unmutated (U-CLL) immunoglobulin heavy variable genes (IGHV). Thus, they contrasted CK cases with 3 or 4 aberrations (low-CK and intermediate-CK, respectively) who followed aggressive disease courses only in the presence of TP53abs. At the other end of the spectrum, patients with CK and +12,+19 displayed an exceptionally indolent profile. Building upon CK, TP53abs and IGHV gene somatic hypermutation status, we propose a novel hierarchical model where patients with high-CK exhibit the worst prognosis, while M-CLL lacking CK or TP53abs as well as CK with +12,+19 show the longest overall survival. In conclusion, CK should not be axiomatically considered unfavorable in CLL, representing a heterogeneous group with variable clinical behavior. High-CK with 655 chromosomal aberrations emerges as prognostically adverse, independently of other biomarkers. Prospective clinical validation is warranted before finally incorporating high-CK in risk stratification of CLL
IL-7 Promotes CD95-Induced Apoptosis in B Cells via the IFN-γ/STAT1 Pathway
Interleukin-7 (IL-7) concentrations are increased in the blood of CD4+ T cell depleted individuals, including HIV-1 infected patients. High IL-7 levels might stimulate T cell activation and, as we have shown earlier, IL-7 can prime resting T cell to CD95 induced apoptosis as well. HIV-1 infection leads to B cell abnormalities including increased apoptosis via the CD95 (Fas) death receptor pathway and loss of memory B cells. Peripheral B cells are not sensitive for IL-7, due to the lack of IL-7Ra expression on their surface; however, here we demonstrate that high IL-7 concentration can prime resting B cells to CD95-mediated apoptosis via an indirect mechanism. T cells cultured with IL-7 induced high CD95 expression on resting B cells together with an increased sensitivity to CD95 mediated apoptosis. As the mediator molecule responsible for B cell priming to CD95 mediated apoptosis we identified the cytokine IFN-γ that T cells secreted in high amounts in response to IL-7. These results suggest that the lymphopenia induced cytokine IL-7 can contribute to the increased B cell apoptosis observed in HIV-1 infected individuals
brainlife.io: A decentralized and open source cloud platform to support neuroscience research
Neuroscience research has expanded dramatically over the past 30 years by
advancing standardization and tool development to support rigor and
transparency. Consequently, the complexity of the data pipeline has also
increased, hindering access to FAIR data analysis to portions of the worldwide
research community. brainlife.io was developed to reduce these burdens and
democratize modern neuroscience research across institutions and career levels.
Using community software and hardware infrastructure, the platform provides
open-source data standardization, management, visualization, and processing and
simplifies the data pipeline. brainlife.io automatically tracks the provenance
history of thousands of data objects, supporting simplicity, efficiency, and
transparency in neuroscience research. Here brainlife.io's technology and data
services are described and evaluated for validity, reliability,
reproducibility, replicability, and scientific utility. Using data from 4
modalities and 3,200 participants, we demonstrate that brainlife.io's services
produce outputs that adhere to best practices in modern neuroscience research
The effects of improving sleep on mental health (OASIS): a randomised controlled trial with mediation analysis
BACKGROUND: Sleep difficulties might be a contributory causal factor in the occurrence of mental health problems. If this is true, improving sleep should benefit psychological health. We aimed to determine whether treating insomnia leads to a reduction in paranoia and hallucinations. METHODS: We did this single-blind, randomised controlled trial (OASIS) at 26 UK universities. University students with insomnia were randomly assigned (1:1) with simple randomisation to receive digital cognitive behavioural therapy (CBT) for insomnia or usual care, and the research team were masked to the treatment. Online assessments took place at weeks 0, 3, 10 (end of therapy), and 22. The primary outcome measures were for insomnia, paranoia, and hallucinatory experiences. We did intention-to-treat analyses. The trial is registered with the ISRCTN registry, number ISRCTN61272251. FINDINGS: Between March 5, 2015, and Feb 17, 2016, we randomly assigned 3755 participants to receive digital CBT for insomnia (n=1891) or usual practice (n=1864). Compared with usual practice, the sleep intervention at 10 weeks reduced insomnia (adjusted difference 4·78, 95% CI 4·29 to 5·26, Cohen's d=1·11; p<0·0001), paranoia (-2·22, -2·98 to -1·45, Cohen's d=0·19; p<0·0001), and hallucinations (-1·58, -1·98 to -1·18, Cohen's d=0·24; p<0·0001). Insomnia was a mediator of change in paranoia and hallucinations. No adverse events were reported. INTERPRETATION: To our knowledge, this is the largest randomised controlled trial of a psychological intervention for a mental health problem. It provides strong evidence that insomnia is a causal factor in the occurrence of psychotic experiences and other mental health problems. Whether the results generalise beyond a student population requires testing. The treatment of disrupted sleep might require a higher priority in mental health provision. FUNDING: Wellcome Trust
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