125 research outputs found

    Contemporary homeschooling arrangements: An analysis of three waves of nationally representative data

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    Homeschooling has increased dramatically in recent decades. During this period of expansion, scholars have reported on growing diversity in the ways that homeschool families educate their children. However, research tends to treat homeschooled children as a uniform group without accounting for differing homeschool arrangements. In this study, we examine the prevalence of four types of homeschool arrangements reported in prior literature as follows: (1) home education supplemented by the use of a private tutor or a homeschool cooperative, (2) home education supplemented by the use of online learning, (3) home education supplemented by part-time enrollment in a brick-and-mortar school, and (4) fully parent-delivered home education. For the analyses, three cross-sectional waves of nationally representative data on homeschool families (n = 1,468) from the National Household Education Survey (NHES: 2012, 2016, 2019) are examined. Results indicate that the four types of homeschool arrangements tested in this study are widespread and that the majority of homeschool families supplement home education with cooperatives and tutors, brick-and-mortar schools, and online education. Homeschool families who continue to perform conventional homeschooling without additional supplements are more likely to be white and less educated with elementary-aged children in the South region of the United States. Homeschool families whose children attend brick-and-mortar schools part-time are less likely to be white and more likely to have secondary school-aged children in urban areas. Use of online education is also higher at the secondary school level

    Homeschooling, social isolation, and life trajectories: An analysis of formerly homeschooled adults

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    A longstanding critique of homeschooling is that it isolates children from mainstream society, depriving them of social experiences needed to thrive as adults. Although a small number of empirical studies challenge this criticism, this research tends to be derived from self-reports of homeschooling parents about their children. In this study, analyses of qualitative interviews (n = 31) and survey data (n = 140) of adults who were homeschooled as children are performed. Most interview participants described conventional and unconventional social experiences that they felt had satisfied their social needs while being homeschooled. Participants who were homeschooled for all or most of their K-12 education had less exposure to mainstream school-based social opportunities but reflected that homeschooling had not hindered their ability to navigate society effectively. Analyses of survey data seemed to echo this finding. No statistical differences on four social and life outcomes (i.e. college attendance, household income, marital status, and subjective wellbeing) were observed between short-term homeschoolers (1-2 years) who spent nearly all of their K-12 education in brick-and-mortar schools and long-term (10-12 years) and substantial (3-9 years) homeschoolers who had less exposure to mainstream social opportunities available in brick-and mortar schools. This study advances the literature by using qualitative and quantitative data to generate key insights on the social and life trajectories of formerly homeschooled adults

    1863-12-28 Colonel Daniel Chaplin and others recommend Captain W. Clarke for promotion

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    https://digitalmaine.com/cw_me_1st_heavy_corr/1150/thumbnail.jp

    Fully Homomorphic Encryption for RAMs

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    We initiate the study of fully homomorphic encryption for RAMs (RAM-FHE). This is a public-key encryption scheme where, given an encryption of a large database DD, anybody can efficiently compute an encryption of P(D)P(D) for an arbitrary RAM program PP. The running time over the encrypted data should be as close as possible to the worst case running time of PP, which may be sub-linear in the data size. A central difficulty in constructing a RAM-FHE scheme is hiding the sequence of memory addresses accessed by PP. This is particularly problematic because an adversary may homomorphically evaluate many programs over the same ciphertext, therefore effectively ``rewinding\u27\u27 any mechanism for making memory accesses oblivious. We identify a necessary prerequisite towards constructing RAM-FHE that we call \emph{rewindable oblivious RAM} (rewindable ORAM), which provides security even in this strong adversarial setting. We show how to construct rewindable ORAM using \emph{symmetric-key doubly efficient PIR (SK-DEPIR)} (Canetti-Holmgren-Richelson, Boyle-Ishai-Pass-Wootters: TCC \u2717). We then show how to use rewindable ORAM, along with virtual black-box (VBB) obfuscation for specific circuits, to construct RAM-FHE. The latter primitive can be heuristically instantiated using existing indistinguishability obfuscation candidates. Overall, we obtain a RAM-FHE scheme where the multiplicative overhead in running time is polylogarithmic in the data size NN. Our basic scheme is single-hop, but we also extend it to get multi-hop RAM-FHE with overhead NϵN^\epsilon for arbitrarily small ϵ>0\epsilon>0. We view our work as the first evidence that RAM-FHE is likely to exist

    Private Anonymous Data Access

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    We consider a scenario where a server holds a huge database that it wants to make accessible to a large group of clients. After an initial setup phase, clients should be able to read arbitrary locations in the database while maintaining privacy (the server does not learn which locations are being read) and anonymity (the server does not learn which client is performing each read). This should hold even if the server colludes with a subset of the clients. Moreover, the run-time of both the server and the client during each read operation should be low, ideally only poly-logarithmic in the size of the database and the number of clients. We call this notion Private Anonymous Data Access (PANDA). PANDA simultaneously combines aspects of Private Information Retrieval (PIR) and Oblivious RAM (ORAM). PIR has no initial setup, and allows anybody to privately and anonymously access a public database, but the server\u27s run-time is linear in the data size. On the other hand, ORAM achieves poly-logarithmic server run-time, but requires an initial setup after which only a single client with a secret key can access the database. The goal of PANDA is to get the best of both worlds: allow many clients to privately and anonymously access the database as in PIR, while having an efficient server as in ORAM. In this work, we construct bounded-collusion PANDA schemes, where the efficiency scales linearly with a bound on the number of corrupted clients that can collude with the server, but is otherwise poly-logarithmic in the data size and the total number of clients. Our solution relies on standard assumptions, namely the existence of fully homomorphic encryption, and combines techniques from both PIR and ORAM. We also extend PANDA to settings where clients can write to the database

    Multi-Key Searchable Encryption, Revisited

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    We consider a setting where users store their encrypted documents on a remote server and can selectively share documents with each other. A user should be able to perform keyword searches over all the documents she has access to, including the ones that others shared with her. The contents of the documents, and the search queries, should remain private from the server. This setting was considered by Popa et al. (NSDI \u2714) who developed a new cryptographic primitive called Multi-Key Searchable Encryption (MKSE), together with an instantiation and an implementation within a system called Mylar, to address this goal. Unfortunately, Grubbs et al. (CCS \u2716) showed that the proposed MKSE definition fails to provide basic security guarantees, and that the Mylar system is susceptible to simple attacks. Most notably, if a malicious Alice colludes with the server and shares a document with an honest Bob then the privacy of all of Bob\u27s search queries is lost. In this work we revisit the notion of MKSE and propose a new strengthened definition that rules out the above attacks. We then construct MKSE schemes meeting our definition. We first give a simple and efficient construction using only pseudorandom functions. This construction achieves our strong security definition at the cost of increasing the server storage overhead relative to Mylar, essentially replicating the document each time it is shared. We also show that high server storage overhead is not inherent, by giving an alternate (albeit impractical) construction that manages to avoid it using obfuscation

    Investigation of interference from canine anti-mouse antibodies in hormone immunoassays

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    Background: Canine anti-mouse antibodies are a potential source of immunoassay interference, but erroneous immunoassay results are not always easily identifiable. Anti-Mullerian hormone (AMH) is a marker for the presence of gonads in dogs, but elevated AMH concentrations in neutered dogs could also be caused by antibody interference. For other assays, a discrepant result obtained after antibody precipitation might indicate antibody interference. Objectives: We aimed to evaluate if canine anti-mouse antibodies are a source of erroneous results in the AMH assay and if antibody precipitation with polyethylene glycol (PEG) is a useful tool for detecting antibody interference in a variety of immunoassays used in the veterinary clinical laboratory. Methods: Twenty-nine positive and 25 negative samples for anti-mouse antibodies were analyzed for AMH, canine total thyroxine (TT4), canine thyroid-stimulating hormone (TSH) and progesterone before and after treatment with PEG. Results that differed by more than four SDs from the intra-assay coefficients of variation were considered discrepant. Elevated AMH concentrations in neutered dogs with anti-mouse antibodies and no visible gonads present were considered evidence of interference. Results: Evidence of antibody interference was found in two samples analyzed for AMH. The presence of anti-mouse antibodies did not lead to a higher proportion of discrepant results after PEG treatment for any of the immunoassays. The overall incidence of discrepant results for healthy controls was very high (73%). Conclusions Canine anti-mouse antibodies are a source of erroneous AMH results. Antibody precipitation with PEG is not a useful tool for detecting interference caused by such antibodies

    Prolactin stimulates precursor cells in the adult mouse hippocampus

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    In the search for ways to combat degenerative neurological disorders, neurogenesis-stimulating factors are proving to be a promising area of research. In this study, we show that the hormonal factor prolactin (PRL) can activate a pool of latent precursor cells in the adult mouse hippocampus. Using an in vitro neurosphere assay, we found that the addition of exogenous PRL to primary adult hippocampal cells resulted in an approximate 50% increase in neurosphere number. In addition, direct infusion of PRL into the adult dentate gyrus also resulted in a significant increase in neurosphere number. Together these data indicate that exogenous PRL can increase hippocampal precursor numbers both in vitro and in vivo. Conversely, PRL null mice showed a significant reduction (approximately 80%) in the number of hippocampal-derived neurospheres. Interestingly, no deficit in precursor proliferation was observed in vivo, indicating that in this situation other niche factors can compensate for a loss in PRL. The PRL loss resulted in learning and memory deficits in the PRL null mice, as indicated by significant deficits in the standard behavioral tests requiring input from the hippocampus. This behavioral deficit was rescued by direct infusion of recombinant PRL into the hippocampus, indicating that a lack of PRL in the adult mouse hippocampus can be correlated with impaired learning and memory

    Developmental and computational perspectives on infant social cognition

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    Adults effortlessly and automatically infer complex pat- terns of goals, beliefs, and other mental states as the causes of others’ actions. Yet before the last decade little was known about the developmental origins of these abilities in early infancy. Our understanding of infant social cognition has now improved dramatically: even preverbal infants appear to perceive goals, preferences (Kushnir, Xu, & Wellman, in press), and even beliefs from sparse observations of inten- tional agents’ behavior. Furthermore, they use these infer- ences to predict others’ behavior in novel contexts and to make social evaluations (Hamlin, Wynn, & Bloom, 2007). Keywords: Social cognition; Cognitive Development; Computational Modeling; Theory of Min

    Physical Activity, Mental Health and Wellbeing of Adults within and during the Easing of COVID-19 Restrictions, in the United Kingdom and New Zealand

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    Physical activity (PA) participation was substantially reduced at the start of the COVID-19 pandemic. The purpose of this study was to assess the association between PA, mental health, and wellbeing during and following the easing of COVID-19 restrictions in the United Kingdom (UK) and New Zealand (NZ). In this study, 3363 adults completed online surveys within 2–6 weeks of initial COVID-19 restrictions (April/May 2020) and once restrictions to human movement had been eased. Outcome measures included the International Physical Activity Questionnaire Short-Form, Depression Anxiety and Stress Scale-9 (mental health) and World Health Organisation-5 Wellbeing Index. There were no differences in PA, mental health or wellbeing between timepoints (p > 0.05). Individuals engaging in moderate or high volume of PA had significantly better mental health (−1.1 and −1.7 units, respectively) and wellbeing (11.4 and 18.6 units, respectively) than individuals who engaged in low PA (p < 0.001). Mental health was better once COVID-19 restrictions were eased (p < 0.001). NZ had better mental health and wellbeing than the UK (p < 0.001). Participation in moderate-to-high volumes of PA was associated with better mental health and wellbeing, both during and following periods of COVID-19 containment, compared to participation in low volumes of PA. Where applicable, during the current or future pandemic(s), moderate-to-high volumes of PA should be encouraged
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