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Home-ownership as a social norm and positional good: subjective well-being evidence from panel data
Much attention has been devoted to examining the absolute benefits
of home-ownership (e.g. security and autonomy). This paper by contrast is
concerned with conceptualising and testing the relative benefits of homeownership;
those benefits that depend on an individual’s status in society.
Home-ownership has previously been analysed as a social norm, implying that
the relative benefits (costs) associated with being an owner (renter) are
positively related to relevant others’ home-ownership values. The theoretical
contribution of this paper is to additionally conceptualise home-ownership as a
positional good, implying that the status of both home-owners and renters is
negatively related to relevant others’ home-ownership consumption.
The empirical contribution of this paper is to quantitatively test for these relative
benefits in terms of subjective well-being. We run fixed effects regressions on
three waves of the British Household Panel Study. We find that i) a strengthening
of relevant others’ home-ownership values is associated with increases
(decreases) in the subjective well-being of home-owners (renters), and ii) an
increase in relevant others’ home-ownership consumption decreases the life
satisfaction of owners but has no effect for renters.
Overall our findings suggest that i) the relative benefit of home-ownership are
both statistically significant and of a meaningful magnitude, and ii) homeownership
is likely to be both a social norm and a positional good. Without
explicitly recognising these relative benefits, policymakers risk overestimating
the contribution of home-ownership to societal well-being
Observational and Physical Classification of Supernovae
This chapter describes the current classification scheme of supernovae (SNe).
This scheme has evolved over many decades and now includes numerous SN Types
and sub-types. Many of these are universally recognized, while there are
controversies regarding the definitions, membership and even the names of some
sub-classes; we will try to review here the commonly-used nomenclature, noting
the main variants when possible. SN Types are defined according to
observational properties; mostly visible-light spectra near maximum light, as
well as according to their photometric properties. However, a long-term goal of
SN classification is to associate observationally-defined classes with specific
physical explosive phenomena. We show here that this aspiration is now finally
coming to fruition, and we establish the SN classification scheme upon direct
observational evidence connecting SN groups with specific progenitor stars.
Observationally, the broad class of Type II SNe contains objects showing strong
spectroscopic signatures of hydrogen, while objects lacking such signatures are
of Type I, which is further divided to numerous subclasses. Recently a class of
super-luminous SNe (SLSNe, typically 10 times more luminous than standard
events) has been identified, and it is discussed. We end this chapter by
briefly describing a proposed alternative classification scheme that is
inspired by the stellar classification system. This system presents our
emerging physical understanding of SN explosions, while clearly separating
robust observational properties from physical inferences that can be debated.
This new system is quantitative, and naturally deals with events distributed
along a continuum, rather than being strictly divided into discrete classes.
Thus, it may be more suitable to the coming era where SN numbers will quickly
expand from a few thousands to millions of events.Comment: Extended final draft of a chapter in the "SN Handbook". Comments most
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Premature mortality in refractory partial epilepsy: does surgical treatment make a difference?
Background: Epilepsy carries an increased risk of premature death. For some people with intractable focal epilepsy, surgery offers hope for a seizure-free life. The authors aimed to see whether epilepsy surgery influenced mortality in people with intractable epilepsy. Methods: The authors audited survival status in two cohorts (those who had surgery and those who had presurgical assessment but did not have surgery). Results: There were 40 known deaths in the non-surgical group (3365 person years of follow-up) and 19 in the surgical group (3905 person-years of follow-up). Non-operated patients were 2.4 times (95% CI 1.4 to 4.2) as likely to die as those who had surgery. They were 4.5 times (95% CI 1.9 to 10.9) as likely to die a probable epilepsy-related death. In the surgical group, those with ongoing seizures 1 year after surgery were 4.0 (95% CI 1.2 to 13.7) times as likely to die as those who were seizure-free or who had only simple partial seizures. Time-dependent Cox analysis showed that the yearly outcome group did not significantly affect mortality (HR 1.3, 95% CI 0.9 to 1.8). Conclusion: Successful epilepsy surgery was associated with a reduced risk of premature mortality, compared with those with refractory focal epilepsy who did not have surgical treatment. To some extent, the reduced mortality is likely to be conferred by inducing freedom from seizures. It is not certain whether better survival is attributable only to surgery, as treatment decisions were not randomised, and there may be inherent differences between the groups
The EFF-1A Cytoplasmic Domain Influences Hypodermal Cell Fusions in C. elegans But Is Not Dependent on 14-3-3 Proteins.
BACKGROUND: Regulatory and biophysical mechanisms of cell-cell fusion are largely unknown despite the fundamental requirement for fused cells in eukaryotic development. Only two cellular fusogens that are not of clear recent viral origin have been identified to date, both in nematodes. One of these, EFF-1, is necessary for most cell fusions in Caenorhabditis elegans. Unregulated EFF-1 expression causes lethality due to ectopic fusion between cells not developmentally programmed to fuse, highlighting the necessity of tight fusogen regulation for proper development. Identifying factors that regulate EFF-1 and its paralog AFF-1 could lead to discovery of molecular mechanisms that control cell fusion upstream of the action of a membrane fusogen. Bioinformatic analysis of the EFF-1A isoform\u27s predicted cytoplasmic domain (endodomain) previously revealed two motifs that have high probabilities of interacting with 14-3-3 proteins when phosphorylated. Mutation of predicted phosphorylation sites within these motifs caused measurable loss of eff-1 gene function in cell fusion in vivo. Moreover, a human 14-3-3 isoform bound to EFF-1::GFP in vitro. We hypothesized that the two 14-3-3 proteins in C. elegans, PAR-5 and FTT-2, may regulate either localization or fusion-inducing activity of EFF-1.
METHODOLOGY/PRINCIPAL FINDINGS: Timing of fusion events was slightly but significantly delayed in animals unable to produce full-length EFF-1A. Yet, mutagenesis and live imaging showed that phosphoserines in putative 14-3-3 binding sites are not essential for EFF-1::GFP accumulation at the membrane contact between fusion partner cells. Moreover, although the EFF-1A endodomain was required for normal rates of eff-1-dependent epidermal cell fusions, reduced levels of FTT-2 and PAR-5 did not visibly affect the function of wild-type EFF-1 in the hypodermis.
CONCLUSIONS/SIGNIFICANCE: Deletion of the EFF-1A endodomain noticeably affects the timing of hypodermal cell fusions in vivo. However, prohibiting phosphorylation of candidate 14-3-3-binding sites does not impact localization of the fusogen. Hypodermal membrane fusion activity persists when 14-3-3 expression levels are reduced
Factors affecting seizure outcome after epilepsy surgery: an observational series
IMPORTANCE: Surgical treatment can bring seizure remission in people with focal epilepsy, but requires careful selection of candidates. OBJECTIVES: To determine which preoperative factors are associated with post-operative seizure outcome. DESIGN: We audited seizure outcome of 693 adults who had resective epilepsy surgery between 1990 and 2010 and used survival analysis to detect preoperatively identifiable risk factors of poor seizure outcome. RESULTS: Seven factors were significantly associated with increased probability of recurrence of seizures with impaired awareness post-surgery: MRI findings (eg hazard ratio adjusted for other variables in the model 2.5; 95% CI 1.6 to 3.8 for normal MRI compared with hippocampal sclerosis (HS)), a history of secondarily generalised convulsive seizures (2.3; 95% CI 1.7 to 3.0 for these seizures in the previous year vs never), psychiatric history (1.3; 95% CI 1.1 to 1.7), learning disability (1.8; 95% CI 1.2 to 2.6), and extratemporal (vs temporal) surgery (1.4; 95% CI 1.02, 2.04). People with an older onset of epilepsy had a higher probability of seizure recurrence (1.01; 95% CI 1.00, 1.02) as did those who had used more anti-epileptic drugs (1.05; 95% CI 1.01, 1.09). Combinations of variables associated with seizure recurrence gave overall low probabilities of 5-year seizure freedom (eg a normal MRI and convulsive seizures in the previous year has a probability of seizure freedom at five years of approximately 0.19). CONCLUSIONS AND RELEVANCE: Readily identified clinical features and investigations are associated with reduced probability of good outcome and need consideration when planning presurgical evaluation
DNA Methylation Changes in Atypical Adenomatous Hyperplasia, Adenocarcinoma In Situ, and Lung Adenocarcinoma
BACKGROUND:Aberrant DNA methylation is common in lung adenocarcinoma, but its timing in the phases of tumor development is largely unknown. Delineating when abnormal DNA methylation arises may provide insight into the natural history of lung adenocarcinoma and the role that DNA methylation alterations play in tumor formation. METHODOLOGY/PRINCIPAL FINDINGS:We used MethyLight, a sensitive real-time PCR-based quantitative method, to analyze DNA methylation levels at 15 CpG islands that are frequently methylated in lung adenocarcinoma and that we had flagged as potential markers for non-invasive detection. We also used two repeat probes as indicators of global DNA hypomethylation. We examined DNA methylation in 249 tissue samples from 93 subjects, spanning the putative spectrum of peripheral lung adenocarcinoma development: histologically normal adjacent non-tumor lung, atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ (AIS, formerly known as bronchioloalveolar carcinoma), and invasive lung adenocarcinoma. Comparison of DNA methylation levels between the lesion types suggests that DNA hypermethylation of distinct loci occurs at different time points during the development of lung adenocarcinoma. DNA methylation at CDKN2A ex2 and PTPRN2 is already significantly elevated in AAH, while CpG islands at 2C35, EYA4, HOXA1, HOXA11, NEUROD1, NEUROD2 and TMEFF2 are significantly hypermethylated in AIS. In contrast, hypermethylation at CDH13, CDX2, OPCML, RASSF1, SFRP1 and TWIST1 and global DNA hypomethylation appear to be present predominantly in invasive cancer. CONCLUSIONS/SIGNIFICANCE:The gradual increase in DNA methylation seen for numerous loci in progressively more transformed lesions supports the model in which AAH and AIS are sequential stages in the development of lung adenocarcinoma. The demarcation of DNA methylation changes characteristic for AAH, AIS and adenocarcinoma begins to lay out a possible roadmap for aberrant DNA methylation events in tumor development. In addition, it identifies which DNA methylation changes might be used as molecular markers for the detection of preinvasive lesions
Fluid Intelligence and Psychosocial Outcome: From Logical Problem Solving to Social Adaptation
While fluid intelligence has proved to be central to executive functioning, logical reasoning and other frontal functions, the role of this ability in psychosocial adaptation has not been well characterized.Lower fluid intelligence scores were associated with physical violence, both in the role of victim and victimizer. Drug intake, especially cannabis, cocaine and inhalants and lower self-esteem were also associated with lower fluid intelligence. Finally, scores on the perceived mental health assessment were better when fluid intelligence scores were higher.Our results show evidence of a strong association between psychosocial adaptation and fluid intelligence, suggesting that the latter is not only central to executive functioning but also forms part of a more general capacity for adaptation to social contexts
Facts, values, and Attention-Deficit Hyperactivity Disorder (ADHD): an update on the controversies
The Hastings Center, a bioethics research institute, is holding a series of 5 workshops to examine the controversies surrounding the use of medication to treat emotional and behavioral disturbances in children. These workshops bring together clinicians, researchers, scholars, and advocates with diverse perspectives and from diverse fields. Our first commentary in CAPMH, which grew out of our first workshop, explained our method and explored the controversies in general. This commentary, which grows out of our second workshop, explains why informed people can disagree about ADHD diagnosis and treatment. Based on what workshop participants said and our understanding of the literature, we make 8 points. (1) The ADHD label is based on the interpretation of a heterogeneous set of symptoms that cause impairment. (2) Because symptoms and impairments are dimensional, there is an inevitable "zone of ambiguity," which reasonable people will interpret differently. (3) Many other variables, from different systems and tools of diagnosis to different parenting styles and expectations, also help explain why behaviors associated with ADHD can be interpreted differently. (4) Because people hold competing views about the proper goals of psychiatry and parenting, some people will be more, and others less, concerned about treating children in the zone of ambiguity. (5) To recognize that nature has written no bright line between impaired and unimpaired children, and that it is the responsibility of humans to choose who should receive a diagnosis, does not diminish the significance of ADHD. (6) Once ADHD is diagnosed, the facts surrounding the most effective treatment are complicated and incomplete; contrary to some popular wisdom, behavioral treatments, alone or in combination with low doses of medication, can be effective in the long-term reduction of core ADHD symptoms and at improving many aspects of overall functioning. (7) Especially when a child occupies the zone of ambiguity, different people will emphasize different values embedded in the pharmacological and behavioral approaches. (8) Truly informed decision-making requires that parents (and to the extent they are able, children) have some sense of the complicated and incomplete facts regarding the diagnosis and treatment of ADHD
TWEAK/Fn14 pathway modulates properties of a human microvascular endothelial cell model of blood brain barrier
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