2,407 research outputs found

    Betting and Belief: Prediction Markets and Attribution of Climate Change

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    Despite much scientific evidence, a large fraction of the American public doubts that greenhouse gases are causing global warming. We present a simulation model as a computational test-bed for climate prediction markets. Traders adapt their beliefs about future temperatures based on the profits of other traders in their social network. We simulate two alternative climate futures, in which global temperatures are primarily driven either by carbon dioxide or by solar irradiance. These represent, respectively, the scientific consensus and a hypothesis advanced by prominent skeptics. We conduct sensitivity analyses to determine how a variety of factors describing both the market and the physical climate may affect traders' beliefs about the cause of global climate change. Market participation causes most traders to converge quickly toward believing the "true" climate model, suggesting that a climate market could be useful for building public consensus.Comment: All code and data for the model is available at http://johnjnay.com/predMarket/. Forthcoming in Proceedings of the 2016 Winter Simulation Conference. IEEE Pres

    Exclusion of Extreme Jurors and Minority Representation: The Effect of Jury Selection Procedures

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    We compare two established jury selection procedures meant to safeguard against the inclusion of biased jurors that are also perceived as causing minorities to be under-represented in juries. The Strike and Replace procedure presents potential jurors one-by-one to the parties, while the Struck procedure presents all potential jurors before the parties exercise vetoes. In equilibrium, Struck more effectively excludes extreme jurors than Strike and Replace but leads to a worse representation of minorities. Simulations suggest that the advantage of Struck in terms of excluding extremes is sizable in a wide range of cases. In contrast, Strike and Replace only provides a significantly better representation of minorities if the minority and majority are heavily polarized. When parameters are estimated to match the parties' selection of jurors by race with jury-selection data from Mississippi in trials against black defendants, the procedures' outcomes are substantially different, and the size of the trade-off between objectives can be quantitatively evaluated

    Exclusion of Extreme Jurors and Minority Representation: The Effect of Jury Selection Procedures

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    We compare two established jury selection procedures meant to safeguard against the inclusion of biased jurors that are also perceived as causing minorities to be under-represented in juries. The Strike and Replace procedure presents potential jurors one-by-one to the parties, while the Struck procedure presents all potential jurors before the parties exercise vetoes. In equilibrium, Struck more effectively excludes extreme jurors than Strike and Replace but leads to a worse representation of minorities. Simulations suggest that the advantage of Struck in terms of excluding extremes is sizable in a wide range of cases. In contrast, Strike and Replace only provides a significantly better representation of minorities if the minority and majority are heavily polarized. When parameters are estimated to match the parties' selection of jurors by race with jury-selection data from Mississippi in trials against black defendants, the procedures' outcomes are substantially different, and the size of the trade-off between objectives can be quantitatively evaluated

    Treatment of cognitive deficits in brain tumour patients:Current status and future directions

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    Purpose of review Increased life expectancy in brain tumour patients had led to the need for strategies that preserve and improve cognitive functioning, as many patients suffer from cognitive deficits. The tumour itself, as well as antitumor treatment including surgery, radiotherapy and chemotherapy, supportive treatment and individual patient factors are associated with cognitive problems. Here, we review the recent literature on approaches that preserve and improve cognitive functioning, including pharmacological agents and rehabilitation programs. Recent findings Minimizing cognitive dysfunction and improving cognitive functioning in brain tumour patients may be achieved both by preserving cognitive functioning during antitumor treatment, including techniques such as awake brain surgery, less invasive radiation therapies such as stereotactic radiotherapy and proton therapy, as well as with interventions including cognitive rehabilitation programmes. Novel rehabilitation programs including computer-based cognitive rehabilitation therapy (CRT) programmes that can be adjusted to the specific patient needs and can be administered at home are promising. Furthermore, personalized/precision medicine approaches to identify patients who are at risk for cognitive decline may facilitate effective treatment strategies in the future. Cognitive functioning has gained greater awareness in the neuro-oncological community, and methods to preserve and improve cognitive functioning have been explored. Rehabilitation programmes for brain tumour patients should be further developed and referred to in clinical practice.Neurolog

    A study of roentgenocephalometric bony landmarks

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    The validity of roentgenocephalometric landmark definitions, as well as the way their determination is affected by individual variation in skeletal morphology and by changes associated with growth, has been tested by several studies of sixty-four human skulls and by an analysis of their radiographs. Furthermore, lateral head films of sixty living persons have been analyzed to check the findings obtained from the skeletal material. A number of landmarks deviated from the generally accepted definitions. This was true for prosthion, infradentale, and in a number of cases for menton and gnathion.Individual local variations in skeletal structure played a role in the roentgenocephalometric location of sella, nasion, prosthion, infradentale, menton, gnathion, and especially point A. Several suggestions have been made for improving the standardization of the determination of some of these landmarks.Because of the considerable shortcomings of point A, a new landmark, point L, has been suggested, tested, and found to be superior.On the basis of theoretical considerations, as well as the findings in our material, it is proposed that the anteroposterior length of the maxilla be determined not by means of a midline structure but as the distance between point L and the dorsal outline of the maxillary tuberositas, for which PTM can be used as a substitute.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33733/1/0000247.pd

    Efficient cationic ring-opening polymerization of diverse cyclic imino ethers: unexpected copolymerization behavior

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    The recently developed fast microwave-assisted cationic ring-opening polymerization procedure for 2-oxazolines seems to be ideally suited for slower polymerizing cyclic imino ether monomers. In this study we report the effect of the cyclic imino ether structure on the polymerization rate under exactly the same microwave-assisted conditions revealing that indeed less reactive cyclic imino ethers, including 2-oxazines as well as 4- and 5-substituted 2-oxazolines, can be polymerized to at least 50% conversion for the slowest monomer, namely 5-methyl-2-butyl-2-oxazoline, within 10 h. In addition, the copolymerization behavior of 4-ethyl-2-butyl-2-oxazoline with 2-methyl-2-oxazoline and 2-phenyl-2-oxazoline unexpectedly revealed faster incorporation of the less reactive 4-ethy1-2-buty1-2-oxazoline monomer compared to 2-phenyl-2-oxazoline due to the increased bulk of the latter monomer amplifying the sterical hindrance for polymerization onto the 4-ethyl-2-butyl-2-oxazolinium propagating species

    The importance of autosomal genes in Kallmann syndrome: genotype-phenotype correlations and neuroendocrine characteristics

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    7 pages, 2 figures, 2 tables.-- et al.Kallmann syndrome (KS) consists of congenital, isolated, idiopathic hypogonadotropic hypogonadism (IHH) and anosmia. The gene responsible for the X-linked form of KS, KAL, encodes a protein, anosmin, that plays a key role in the migration of GnRH neurons and olfactory nerves to the hypothalamus. In addition to X-linked pedigrees, autosomal dominant and recessive kindreds with KS have been reported. The relative importance of these autosomal vs. X-linked genes in producing KS, and the frequency of KAL mutations, are currently unknown because these are rare disorders and large series are unusual. We examined 101 individuals with IHH (+/- anosmia) and their families to determine their modes of inheritance, incidence of mutations in the coding sequence of KAL, genotype-phenotype correlations, and [in a subset (n = 38)] their neuroendocrine phenotype. Of the 101 patients, 59 had true KS (IHH + anosmia/hyposmia); whereas, in the remaining 42, no anosmia was evident in the patients or their families. Of the 59 KS patients, 21 were familial, whereas 38 were sporadic cases. Mutations in the coding sequence of KAL were identified in only 3 of 21 familial cases (14%) and 4 of 38 (11%) of the sporadic cases. Of the X-linked cases confirmed by mutational analysis, only 1 of 3 pedigrees appeared X-linked by inspection whereas the other 2 contained only affected brothers. Female members of known KAL mutation families (n = 3) exhibited no reproductive phenotype and were not anosmic, whereas families with anosmic women (n = 3) were not found to carry mutations in KAL. Mutations were uniformly absent in nonanosmic IHH probands (n = 42), as well as in families with both anosmic and nonanosmic members (n = 2). Overall, 4 novel mutations were identified (C172R, R191x, R457x, and delC@L600). With respect to neuroendocrine phenotype, KS men with documented KAL mutations (n = 8) had completely apulsatile LH secretion, whereas those with autosomal modes of inheritance demonstrated a more variable spectrum with evidence of enfeebled (but present) GnRH-induced LH pulses. Our conclusions are: 1) Confirmed mutations in the coding sequence of the KAL gene occur in the minority of KS cases, i.e. only 14% of familial and 11% of sporadic cases; 2) The majority of familial (and presumably sporadic) cases of KS are caused by defects in at least two autosomal genes that are currently unknown; 3) Obligate female carriers in families with KAL mutations have no discernible phenotype; 4) KAL mutations are uniformly absent in patients with either normosmic IHH or in families with both anosmic and nonanosmic individuals; and 5) Patients with KAL mutations have apulsatile LH secretion consistent with a complete absence of GnRH migration of GnRH cells into the hypothalamus, whereas evidence of present (but enfeebled) GnRH-induced LH pulses may be present in autosomal KS cases. Taken together, these findings suggest that autosomal genes account for the majority of familial cases of KS, and that unique neuroendocrine phenotypes consistent with some GnRH neuronal migration may exist in these patients.Supported by funding from CAPES, Brasilia, Brazil (to L.M.B.O.).Peer reviewe
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