665 research outputs found

    Preventing reverse engineering of black-box classifiers

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    Machine learning (ML) models trained for various purposes are generally kept confidential, e.g., due to their commercial value, proprietary nature of training data, etc. Therefore, commercial cloud-based machine-learning service providers protect their ML models even as they provide one or more services to customers that employ ML models. For example, a service enables a customer to upload an observation, e.g., an image, and receive a label for the observation, generated by a ML model that’s trained to determine labels for images. Recent research has shown that given a sufficient number of observations and returned labels, it is possible to reverse engineer the ML model that generated the labels. This disclosure presents techniques that thwart reverse-engineering efforts, e.g., by adversarial actors, by returning, for a small fraction of input queries, not a true but a near-true class label

    Self-reported Follow-up Care Needs Can be Met in Both Facility and Self-managed Abortion: Evidence from Low- and Middle-income Countries

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    Objective: To understand in-facility follow-up care-seeking behavior among both people who self-managed medication abortions (SMA) and those who obtained facility-managed care in six countries and to explore factors that contribute to meeting individual’s self-reported care needs that are core to person-centered care. Study Design: We conducted a qualitative thematic analysis of 67 in-depth interviews conducted with facility or SMA seekers. We first classified individuals as having their care needs met or not, and whether they sought follow-up care. We then identified predisposing, enabling, or need factors that contributed to having care needs met or not. Results: A total of n=67 participants were included in this analysis from six countries. The majority of participants (n=59, 88%) had their care needs met and half (n=33, 49%) sought follow-up care in a facility. Most participants, both at facilities and through SMA, reported their needs were met. Having support from family or accompaniment groups (activists who provide abortion guidance outside of clinical settings), knowing what to expect, and living close to a facility were key enabling factors that allowed individuals to have their care needs met via a facility follow-up visit or to feel confident completing their abortion at home. Inhibiting factors including health system challenges; stigma from providers; legal risk; unsupportive family; and uncertainty prevented some from having their care needs met. Conclusion: Medication abortion follow-up care needs can be met both in and outside of health facilities. Attention towards supporting enabling factors to meet client needs is essential to person-centered abortion care provision

    Collaborating to Meet the Standards: Implications for Professional Development

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    Researchers from the University of Georgia interviewed 27 Mathematics 1 teachers about their experiences during the first year of the high school implementation of the Georgia Performance Standards (GPS). We report our findings about teachers’ experiences with Mathematics 1 professional development and describe features of professional development that teachers identified as most beneficial. Some teachers offered suggestions for professional development that differed from the professional development they had experienced. In addition, we found that many teachers used collaborative strategies to meet the demands of the new curriculum and the perceived inadequacies of resources and training. We discuss the various models of collaboration that teachers described and conclude with a discussion of the implications of our findings for future professional development that supports the GPS

    Paper 2: Collaborating to Meet the Standards: Implications for Professional Development

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    Researchers from the University of Georgia interviewed 27 Mathematics 1 teachers about their experiences during the first year of the high school implementation of the Georgia Performance Standards (GPS). We report our findings about teachers’ experiences with Mathematics 1 professional development and describe features of professional development that teachers identified as most beneficial. Some teachers offered suggestions for professional development that differed from the professional development they had experienced. In addition, we found that many teachers used collaborative strategies to meet the demands of the new curriculum and the perceived inadequacies of resources and training. We discuss the various models of collaboration that teachers described and conclude with a discussion of the implications of our findings for future professional development that supports the GPS

    Behavioral evaluation of mice deficient in GABAB(1) receptor isoforms in tests of unconditioned anxiety

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    Rationale: Emerging data support a role for GABAB receptors in anxiety. GABAB receptors are comprised of a heterodimeric complex of GABAB1 and GABAB2 receptor subunits. The predominant neuronal GABAB1 receptor isoforms are GABAB(1a) and GABAB(1b). Recent findings indicate specific roles for these isoforms in conditioned fear responses, although their influence on behavior in tests of unconditioned anxiety is unknown. Objective: The aim of this study was to examine the role of the GABAB(1) isoforms in unconditioned anxiety. Materials and methods: Mice deficient in the GABAB(1a) or GABAB(1b) receptor isoforms were examined in a battery of anxiety tests. Results: In most tests, genotype did not significantly affect anxious behavior, including the elevated plus maze, marble burying, and stress-induced hypothermia tests. Corticosterone and adrenocorticotropic hormone levels were similarly unaffected by genotype. Female, but not male, {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{a}}} \right)}}} and {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{b}}} \right)}}} mice showed increased anxiety relative to wild-type controls in the elevated zero maze. In the staircase test, male {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{b}}} \right)}}} mice defecated more than male {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{a}}} \right)}}} mice, although no other test parameter was influenced by genotype. In the light-dark box, female {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{a}}} \right)}}} mice spent less time in the light compartment compared to the {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{b}}} \right)}}} females, whereas male {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{b}}} \right)}}} mice made fewer light-dark transitions than {\text{GABA}}^{{ - \mathord{\left/ {\vphantom { - - }} \right. \kern-\nulldelimiterspace} - }}_{{{\text{B}}{\left( {1{\text{a}}} \right)}}} males. Conclusions: Specific roles for either GABAB(1) isoform in unconditioned anxiety were not explicit. This differs from their contribution in conditioned anxiety and from the anxious phenotype of GABAB1 and GABAB2 subunit knockout mice. The findings suggest that the GABAB(1) isoforms have specific relevance for anxiety with a cognitive component, rather than for innate anxiety per s

    DOOp, an automated wrapper for DAOSPEC

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    Large spectroscopic surveys such as the Gaia-ESO Survey produce huge quantities of data. Automatic tools are necessary to efficiently handle this material. The measurement of equivalent widths in stellar spectra is traditionally done by hand or with semi-automatic procedures that are time-consuming and not very robust with respect to the repeatability of the results. The program DAOSPEC is a tool that provides consistent measurements of equivalent widths in stellar spectra while requiring a minimum of user intervention. However, it is not optimised to deal with large batches of spectra, as some parameters still need to be modified and checked by the user. Exploiting the versatility and portability of BASH, we have built a pipeline called DAOSPEC Option Optimiser (DOOp) automating the procedure of equivalent widths measurement with DAOSPEC. DOOp is organised in different modules that run one after the other to perform specific tasks, taking care of the optimisation of the parameters needed to provide the final equivalent widths, and providing log files to ensure better control over the procedure. In this paper, making use of synthetic and observed spectra, we compare the performance of DOOp with other methods, including DAOSPEC used manually. The measurements made by DOOp are identical to the ones produced by DAOSPEC when used manually, while requiring less user intervention, which is convenient when dealing with a large quantity of spectra. DOOp shows its best performance on high-resolution spectra (R>20 000) and high signal-to-noise ratio (S/N>30), with uncertainties ranging from 6 m{\AA} to 2 m{\AA}. The only subjective parameter that remains is the normalisation, as the user still has to make a choice on the order of the polynomial used for the continuum fitting. As a test, we use the equivalent widths measured by DOOp to re-derive the stellar parameters of four well-studied stars

    Association of Maternal age 35 years and over and prenatal care utilization, preterm birth, and low birth weight, Mexico 2008–2019

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    Objective: We compared prenatal care utilization, preterm birth, and low birth weight neonates among women 35 years and older compared to women 20-34 years old in Mexico, 2008-2019. Methods: We used birth certificate data and conducted a historical cohort study of all singleton live births in Mexico from 2008-2019. Study outcomes were inadequate prenatal care (timing of initiation of care and number of visits), preterm birth, and low birth weight. We compared outcomes among women 35-39, 40-44, and 45-49 with births to women 20-34. We used logistic regression to account for individual and contextual confounders. Results: We included a total of N=19,526,922 births; 11.9% (n=2,325,725) were to women 35 and older. Compared to women aged 20 to 34, the oldest (45-49 years old) were more likely to reside in poorer communities, have less education, and be uninsured. The odds of inadequate prenatal care (aOR 1.12 95% CI 1.09-1.15 p Conclusion: Women who deliver at 35 years old and over are a heterogeneous group in Mexico. Being 35 years old and older is associated with increases in preterm birth and low birth weight neonates. Women who give birth between 45-49 may be especially vulnerable

    FAMA: An automatic code for stellar parameter and abundance determination

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    The large amount of spectra obtained during the epoch of extensive spectroscopic surveys of Galactic stars needs the development of automatic procedures to derive their atmospheric parameters and individual element abundances. Starting from the widely-used code MOOG by C. Sneden, we have developed a new procedure to determine atmospheric parameters and abundances in a fully automatic way. The code FAMA (Fast Automatic MOOG Analysis) is presented describing its approach to derive atmospheric stellar parameters and element abundances. The code, freely distributed, is written in Perl and can be used on different platforms. The aim of FAMA is to render the computation of the atmospheric parameters and abundances of a large number of stars using measurements of equivalent widths as automatic and as independent of any subjective approach as possible. It is based on the simultaneous search for three equilibria: excitation equilibrium, ionization balance, and the relationship between \fei\ and the reduced equivalent widths. FAMA also evaluates the statistical errors on individual element abundances and errors due to the uncertainties in the stellar parameters. The convergence criteria are not fixed 'a priori' but are based on the quality of the spectra. In this paper we present tests performed on the Solar spectrum EWs which tests the dependency on the initial parameters, and the analysis of a sample of stars observed in Galactic open and globular clusters.Comment: A&A accepted, 12 pages, 6 figures, 3 table

    GABA B(1)

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    Associations Between Pet Ownership and Attitudes Toward Pets With Youth Socioemotional Outcomes

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    Evidence regarding the effects of pet ownership and related variables on youth socioemotional development is mixed. Inconsistencies across studies may be due to a variety of factors, including the use of different outcomes measured across studies, small potential effect sizes, and use of selected samples. In addition, studies have not systematically controlled for demographic characteristics that may bias results, nor have studies systematically examined whether effects are consistent across different subgroups. The present study examined the impact of pet ownership and attitudes toward pets on four measures of youth socioemotional outcomes: delinquency, depressed mood, empathy, and prosocial behavior. Linear mixed-effect regression analyses were conducted on 342 youth (48.0% male) aged 9–19 (M = 14.05, SD = 1.77) from a racially, ethnically, and socioeconomically diverse sample. The majority (59.1%) of youth currently lived with a dog or cat and all participants completed the Pet Attitude Scale-Modified. Pet owners reported lower delinquency and higher empathy than non-owners; however, group differences became non-significant once demographic factors were controlled for. Attitudes toward pets was significantly associated with all four outcomes. More positive attitudes was modestly associated with lower delinquency (β = -0.22, p < 0.001) and higher empathy (β = 0.31, p < 0.001), with smaller effects for depressed mood (β = -0.12, p = 0.04) and prosocial behavior (β = 0.12, p = 0.02). For delinquency, empathy, and prosocial behavior, effects were only slightly attenuated and remained statistically significant after controlling for gender, age, race/ethnicity, family socioeconomic status, and pet ownership, although the effect for depressed mood became non-significant after inclusion of these demographic factors. While there was some variability in effect sizes across different subgroups, none of the interactions between attitudes toward pets and gender, race/ethnicity, age, family SES, or pet ownership was statistically significant, indicating that the effects may transcend individual differences in demographic characteristics. Overall, the study adds to a growing body of work supporting a positive relationship between emotional bonds with pets and youth socioemotional outcomes and offers potential explanations for inconsistencies across previous studies
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