42 research outputs found

    Usable Secure Private Search

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    Real-world applications commonly require untrusting parties to share sensitive information securely. This article describes a secure anonymous database search (SADS) system that provides exact keyword match capability. Using a new reroutable encryption and the ideas of Bloom filters and deterministic encryption, SADS lets multiple parties efficiently execute exact-match queries over distributed encrypted databases in a controlled manner. This article further considers a more general search setting allowing similarity searches, going beyond existing work that considers similarity in terms of error tolerance and Hamming distance. This article presents a general framework, built on the cryptographic and privacy-preserving guarantees of the SADS primitive, for engineering usable private secure search systems

    Rapid intrapartum test for maternal group B streptococcal colonisation and its effect on antibiotic use in labouring women with risk factors for early-onset neonatal infection (GBS2): cluster randomised trial with nested test accuracy study

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    Background: Mother-to-baby transmission of group B Streptococcus (GBS) is the main cause of early-onset infection. We evaluated whether, in women with clinical risk factors for early neonatal infection, the use of point-of-care rapid intrapartum test to detect maternal GBS colonisation reduces maternal antibiotic exposure compared with usual care, where antibiotics are administered due to those risk factors. We assessed the accuracy of the rapid test in diagnosing maternal GBS colonisation, against the reference standard of selective enrichment culture. Methods: We undertook a parallel-group cluster randomised trial, with nested test accuracy study and microbiological sub-study. UK maternity units were randomised to a strategy of rapid test (GeneXpert GBS system, Cepheid) or usual care. Within units assigned to rapid testing, vaginal-rectal swabs were taken from women with risk factors for vertical GBS transmission in established term labour. The trial primary outcome was the proportion of women receiving intrapartum antibiotics to prevent neonatal early-onset GBS infection. The accuracy of the rapid test was compared against the standard of selective enrichment culture in diagnosing maternal GBS colonisation. Antibiotic resistance profiles were determined in paired maternal and infant samples. Results: Twenty-two maternity units were randomised and 20 were recruited. A total of 722 mothers (749 babies) participated in rapid test units; 906 mothers (951 babies) were in usual care units. There was no evidence of a difference in the rates of intrapartum antibiotic prophylaxis (relative risk 1.16, 95% CI 0.83 to 1.64) between the rapid test (41%, 297/716) and usual care (36%, 328/906) units. No serious adverse events were reported. The sensitivity and specificity measures of the rapid test were 86% (95% CI 81 to 91%) and 89% (95% CI 85 to 92%), respectively. Babies born to mothers who carried antibiotic-resistant Escherichia coli were more likely to be colonised with antibiotic-resistant strains than those born to mothers with antibiotic-susceptible E. coli. Conclusion: The use of intrapartum rapid test to diagnose maternal GBS colonisation did not reduce the rates of antibiotics administered for preventing neonatal early-onset GBS infection than usual care, although with considerable uncertainty. The accuracy of the rapid test is within acceptable limits. Trial registration: ISRCTN74746075. Prospectively registered on 16 April 2015

    Access Control Encryption for General Policies from Standard Assumptions

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    Functional encryption enables fine-grained access to encrypted data. In many scenarios, however, it is important to control not only what users are allowed to read (as provided by traditional functional encryption), but also what users are allowed to send. Recently, Damgård et al. (TCC 2016) introduced a new cryptographic framework called access control encryption (ACE) for restricting information flow within a system in terms of both what users can read as well as what users can write. While a number of access control encryption schemes exist, they either rely on strong assumptions such as indistinguishability obfuscation or are restricted to simple families of access control policies. In this work, we give the first ACE scheme for arbitrary policies from standard assumptions. Our construction is generic and can be built from the combination of a digital signature scheme, a predicate encryption scheme, and a (single-key) functional encryption scheme that supports randomized functionalities. All of these primitives can be instantiated from standard assumptions in the plain model and therefore, we obtain the first ACE scheme capable of supporting general policies from standard assumptions. One possible instantiation of our construction relies upon standard number-theoretic assumptions (namely, the DDH and RSA assumptions) and standard lattice assumptions (namely, LWE). Finally, we conclude by introducing several extensions to the ACE framework to support dynamic and more fine-grained access control policies

    International collaborative follow - up investigation of graduating high school students’ understandings of the nature of scientific inquiry: is progress Being made?

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    Understandings of the nature of scientific inquiry (NOSI), as opposed to engaging students in inquiry learning experiences, are included in science education reform documents around the world. However, little is known about what students have learned about NOSI during their pre-college school years. The purpose of this large-scale follow-up international project (i.e. 32 countries and regions, spanning six continents and including 3917 students for the high school sample) was to collect data on what exiting high school students have learned about NOSI. Additionally, the study investigated changes in 12th grade students’ NOSI understandings compared to seventh grade (i.e. 20 countries and regions) students’ understandings from a prior investigation [Lederman et al. (2019). An international collaborative investigation of beginning seventh grade students’ understandings of scientific inquiry: Establishing a baseline. Journal of Research in Science Teaching, 56(4), 486–515. https://doi.org/10.1002/tea.21512]. This study documents and discusses graduating high school students’ understandings and compares their understandings to seventh grade students’ understandings of the same aspects of scientific inquiry for each country. It is important to note that collecting data from each of the 130+ countries globally was not feasible. Similarly, it was not possible to collect data from every region of each country. A concerted effort was made, however, to provide a relatively representative picture of each country and the world

    Persistent KSHV infection increases EBV-associated tumor formation In vivo via enhanced EBV lytic gene expression

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    The human tumor viruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) establish persistent infections in B cells. KSHV is linked to primary effusion lymphoma (PEL), and 90% of PELs also contain EBV. Studies on persistent KSHV infection in vivo and the role of EBV co-infection in PEL development have been hampered by the absence of small animal models. We developed mice reconstituted with human immune system components as a model for KSHV infection and find that EBV/KSHV dual infection enhanced KSHV persistence and tumorigenesis. Dual-infected cells displayed a plasma cell-like gene expression pattern similar to PELs. KSHV persisted in EBV-transformed B cells and was associated with lytic EBV gene expression, resulting in increased tumor formation. Evidence of elevated lytic EBV replication was also found in EBV/KSHV dually infected lymphoproliferative disorders in humans. Our data suggest that KSHV augments EBV-associated tumorigenesis via stimulation of lytic EBV replication

    LIGHT/LTβR signaling regulates self-renewal and differentiation of hematopoietic and leukemia stem cells.

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    The production of blood cells during steady-state and increased demand depends on the regulation of hematopoietic stem cell (HSC) self-renewal and differentiation. Similarly, the balance between self-renewal and differentiation of leukemia stem cells (LSCs) is crucial in the pathogenesis of leukemia. Here, we document that the TNF receptor superfamily member lymphotoxin-β receptor (LTβR) and its ligand LIGHT regulate quiescence and self-renewal of murine and human HSCs and LSCs. Cell-autonomous LIGHT/LTβR signaling on HSCs reduces cell cycling, promotes symmetric cell division and prevents primitive HSCs from exhaustion in serial re-transplantation experiments and genotoxic stress. LTβR deficiency reduces the numbers of LSCs and prolongs survival in a murine chronic myeloid leukemia (CML) model. Similarly, LIGHT/LTβR signaling in human G-CSF mobilized HSCs and human LSCs results in increased colony forming capacity in vitro. Thus, our results define LIGHT/LTβR signaling as an important pathway in the regulation of the self-renewal of HSCs and LSCs

    Dysfunctional Effects of a Conflict in a Healthcare Organization / Дисфункциональный Аспект Конфликта В Организации Здравоохранения

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    Конфликты на рабочем месте становятся часто встречаемым явлением вследствие постоянных изменений и трансформаций в системе современных лечебных заведений больничной помощи и динамического взаимодействия между медицинскими специалистами. ЦЕЛЬ: Целью настоящей работы является исследование мнения медицинских работников в отношении воздействия на них потенциальных деструктивных последствий конфликта во время работы. МАТЕРИАЛЫ И МЕТОДЫ: Был проведён непосредственный индивидуальный анкетный опрос среди 279 медицинских работников в 4 многопрофильных больницах. В целях исследования была использована группа вопросов, отражающих негативные реакции и последствия конфликта в отношении медицинских работников, выступающих в роли прямых или косвеных участников в нём. Данные анализированы при помощи дескриптивной статистики и непараметрического анализа при уровне значимости нулевой гипотезы p < 0.05. РЕЗУЛЬТАТЫ: Конфликты на рабочем месте усугубляют в значительной степени стресс, психологическое напряжение и эмоциональное истощение медицинских специалистов. Конфронтация между участниками конфликтного взаимодействия проявляется как катализатор конфликта и усиливает проявление враждебных действий, гнева и агрессии. Деструктивные последствия вследствие конфликта выражаются в пониженной удовлетворённости и в демотивации трудовой деятельности. Возникшие противоречия ухудшают сотрудничество в коллективе и препятствуют совместному решению проблем в соответствующей структуре здравоохранения. ЗАКЛЮЧЕНИЕ: Конфликт в больницах оказывает в значительной степени деструктивное воздействие на отдельного работника, что в свою очередь требует современной идентификации, оперативного и эффективного вмешательства с целью свести к минимуму его неблагоприятные последствия

    Interleukins 12 and 15 induce cytotoxicity and early NK-cell differentiation in type 3 innate lymphoid cells

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    Type 3 innate lymphoid cells (ILC3s) fulfill protective functions at mucosal surfaces via cytokine production. Although their plasticity to become ILC1s, the innate counterparts of type 1 helper T cells, has been described previously, we report that they can differentiate into cytotoxic lymphocytes with many characteristics of early differentiated natural killer (NK) cells. This transition is promoted by the proinflammatory cytokines interleukin 12 (IL-12) and IL-15, and correlates with expression of the master transcription factor of cytotoxicity, eomesodermin (Eomes). As revealed by transcriptome analysis and flow cytometric profiling, differentiated ILC3s express CD94, NKG2A, NKG2C, CD56, and CD16 among other NK-cell receptors, and possess all components of the cytotoxic machinery. These characteristics allow them to recognize and kill leukemic cells with perforin and granzymes. Therefore, ILC3s can be harnessed for cytotoxic responses via differentiation under the influence of proinflammatory cytokines
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