2,167 research outputs found

    Oil spill source identification using colorimetric detection

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    The colorimetric detection of polycyclic aromatic hydrocarbons (PAHs) was investigated for the quick and easy identification of likely oil spill offenders. In this new technology, photochromic compounds were used to sense PAHs by varying their photoswitching capacity. To that end, three photochromes were designed and showed varying degrees of photoswitching inhibition depending on PAH analyte, photochrome and excitation wavelength. PAH mixtures that mimic oil spills showed the same varying response and demonstrated the accuracy of this technology. To prove the applicability of this technology, an array was assembled using the three photochromes at three excitation wavelengths and tested against authentic crude oil samples. Not only could these samples be differentiated, weathering of two distinctly different oil samples showed limited variation in response, demonstrating that this may be a viable technique for in situ oil identification

    A new generation of magnetoencephalography: room temperature measurements using optically-pumped magnetometers

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    Advances in the field of quantum sensing mean that magnetic field sensors, operating at room temperature, are now able to achieve sensitivity similar to that of cryogenically cooled devices (SQUIDs). This means that room temperature magnetoencephalography (MEG), with a greatly increased flexibility of sensor placement can now be considered. Further, these new sensors can be placed directly on the scalp surface giving, theoretically, a large increase in the magnitude of the measured signal. Here, we present recordings made using a single optically-pumped magnetometer (OPM) in combination with a 3D-printed head-cast designed to accurately locate and orient the sensor relative to brain anatomy. Since our OPM is configured as a magnetometer it is highly sensitive to environmental interference. However, we show that this problem can be ameliorated via the use of simultaneous reference sensor recordings. Using median nerve stimulation, we show that the OPM can detect both evoked (phase-locked) and induced (non-phase-locked oscillatory) changes when placed over sensory cortex, with signals ~4 times larger than equivalent SQUID measurements. Using source modelling, we show that our system allows localisation of the evoked response to somatosensory cortex. Further, source-space modelling shows that, with 13 sequential OPM measurements, source-space signal-to-noise ratio (SNR) is comparable to that from a 271-channel SQUID system. Our results highlight the opportunity presented by OPMs to generate uncooled, potentially low-cost, high SNR MEG systems

    The imperative usage of an innovated Biscuit-Shaped Tenon Groove Machine towards Technology Model for interior design technology program in technical education

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    This study was conducted in order to create and effectively use an Innovated Biscuit-Shaped Tenon Groove Machine towards Technology Model for Interior Design technology program in Technical education so that the creative learners could use it to support instruction in school, the study was conducted at Cebu Technological University- Pinamungajan Campus, Pinamungajan, Cebu. The output of this study was regarded as an alternative technology tool of CTU- Pinamungajan Campus, Pinamungajan, Cebu where the study is being done. This study used quasi-experimental techniques, specifically survey research. 90 students and 5 professors/instructors were given questionnaires to complete for evaluation. Weighted mean and t-test were used to analyze the collected data. Based on the results and following a careful analysis, it is concluded that Innovative Biscuit-Shaped Tenon Groove Machine meets campus needs and standards

    Interferon-Responsive Genes Are Targeted during the Establishment of Human Cytomegalovirus Latency.

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    Human cytomegalovirus (HCMV) latency is an active process which remodels the latently infected cell to optimize latent carriage and reactivation. This is achieved, in part, through the expression of viral genes, including the G-protein-coupled receptor US28. Here, we use an unbiased proteomic screen to assess changes in host proteins induced by US28, revealing that interferon-inducible genes are downregulated by US28. We validate that major histocompatibility complex (MHC) class II and two pyrin and HIN domain (PYHIN) proteins, myeloid cell nuclear differentiation antigen (MNDA) and IFI16, are downregulated during experimental latency in primary human CD14+ monocytes. We find that IFI16 is targeted rapidly during the establishment of latency in a US28-dependent manner but only in undifferentiated myeloid cells, a natural site of latent carriage. Finally, by overexpressing IFI16, we show that IFI16 can activate the viral major immediate early promoter and immediate early gene expression during latency via NF-κB, a function which explains why downregulation of IFI16 during latency is advantageous for the virus.IMPORTANCE Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus which infects 50 to 100% of humans worldwide. HCMV causes a lifelong subclinical infection in immunocompetent individuals but is a serious cause of mortality and morbidity in the immunocompromised and neonates. In particular, reactivation of HCMV in the transplant setting is a major cause of transplant failure and related disease. Therefore, a molecular understanding of HCMV latency and reactivation could provide insights into potential ways to target the latent viral reservoir in at-risk patient populations

    Use of long‐acting reversible contraception in a cluster‐random sample of female sex workers in Kenya

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    Objective: To assess correlates of long-acting reversible contraceptive (LARC) use, and explore patterns of LARC use among female sex workers (FSWs) in Kenya. Methods: Baseline cross-sectional data were collected between September 2016 and May 2017 in a cluster-randomized controlled trial in Mombasa. Eligibility criteria included current sex work, age 16–34 years, not pregnant, and not planning pregnancy. Peer educators recruited FSWs from randomly selected sex-work venues. Multiple logistic regression identified correlates of LARC use. Prevalence estimates were weighted to adjust for variation in FSW numbers recruited across venues. Results: Among 879 participants, the prevalence of contraceptive use was 22.6% for implants and 1.6% for intra-uterine devices (IUDs). LARC use was independently associated with previous pregnancy (adjusted odds ratio for one pregnancy, 11.4; 95% confidence interval, 4.25–30.8), positive attitude to and better knowledge of family planning, younger age, and lower education. High rates of adverse effects were reported for all methods. Conclusion: The findings suggest that implant use has increased among FSWs in Kenya. Unintended pregnancy risks remain high and IUD use is negligible. Although LARC rates are encouraging, further intervention is required to improve both uptake (particularly of IUDs) and greater access to family planning services

    A Conformal Split-Ring Loop as a Self-Resonator for Wireless Power Transfer

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    Effect of a mobile phone intervention for female sex workers on unintended pregnancy in Kenya (WHISPER or SHOUT): a cluster-randomised controlled trial

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    Background: Female sex workers in low-income and middle-income countries face high risks of unintended pregnancy. We developed a 12-month, multifaceted short messaging service intervention (WHISPER) for female sex workers in Kenya who had the potential to become pregnant, to improve their contraceptive knowledge and behaviours. The aim of this study was to assess the effectiveness of the intervention to reduce the incidence of unintended pregnancy among sex workers in Kenya compared with an equal-attention control group receiving nutrition-focused messages (SHOUT). Methods: Our two-arm, cluster-randomised controlled trial was done in sex-work venues in two subcounties of Mombasa, Kenya (Kisauni and Changamwe). Participants, aged 16–34 years, not pregnant or planning pregnancy, able to read text messages in English, residing in the study area, and who had a personal mobile phone with one of two phone networks, were recruited from 93 randomly selected sex-work venues (clusters). Random cluster allocation (1:1) to the intervention or control group was concealed from participants and researchers until the intervention started. Both groups received text messages in English delivered two to three times per week for 12 months (137 messages in total), as well as additional on-demand messages. Message content in the intervention group focused on promotion of contraception, particularly long-acting reversible contraception and dual method contraceptive use; message content in the control group focused on promotion of nutritional knowledge and practices, including food safety, preparation, and purchasing. The primary endpoint, analysed in all participants who were randomly assigned and attended at least one follow-up visit, compared unintended pregnancy incidence between groups using discrete-time survival analysis at 6 and 12 months. This trial is registered with Australian New Zealand Clinical Trials Registry, ACTRN12616000852459, and is closed to new participants. Findings: Between Sept 14, 2016, and May 16, 2017, 1728 individuals were approached to take part in the study. Of these, 1155 were eligible for full screening, 1035 were screened, and 882 were eligible, enrolled, and randomly assigned (451 participants from 47 venues in the intervention group; 431 participants from 46 venues in the control group). 401 participants from the intervention group and 385 participants from the control group were included in the primary analysis. Incidence of unintended pregnancy was 15·5 per 100 person-years in the intervention group and 14·7 per 100 person-years in the control group (hazard ratio 0·98, 95% CI 0·69–1·39). Interpretation The intervention had no measurable effect on unintended pregnancy incidence. Mobile health interventions, even when acceptable and rigorously designed, are unlikely to have a sufficient effect on behaviour among female sex workers to change pregnancy incidence when used in isolation. Funding: National Health and Medical Research Council of Australia

    High-fidelity quantum driving

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    The ability to accurately control a quantum system is a fundamental requirement in many areas of modern science such as quantum information processing and the coherent manipulation of molecular systems. It is usually necessary to realize these quantum manipulations in the shortest possible time in order to minimize decoherence, and with a large stability against fluctuations of the control parameters. While optimizing a protocol for speed leads to a natural lower bound in the form of the quantum speed limit rooted in the Heisenberg uncertainty principle, stability against parameter variations typically requires adiabatic following of the system. The ultimate goal in quantum control is to prepare a desired state with 100% fidelity. Here we experimentally implement optimal control schemes that achieve nearly perfect fidelity for a two-level quantum system realized with Bose-Einstein condensates in optical lattices. By suitably tailoring the time-dependence of the system's parameters, we transform an initial quantum state into a desired final state through a short-cut protocol reaching the maximum speed compatible with the laws of quantum mechanics. In the opposite limit we implement the recently proposed transitionless superadiabatic protocols, in which the system perfectly follows the instantaneous adiabatic ground state. We demonstrate that superadiabatic protocols are extremely robust against parameter variations, making them useful for practical applications.Comment: 17 pages, 4 figure

    Shelf space strategy in long-tail markets

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    The Internet is known to have had a powerful impact on on-line retailer strategies in markets characterised by long-tail distribution of sales. Such retailers can exploit the long tail of the market, since they are effectively without physical limit on the number of choices on offer. Here we examine two extensions of this phenomenon. First, we introduce turnover into the long-tail distribution of sales. Although over any given period such as a week or a month, the distribution is right-skewed and often power law distributed, over time there is considerable turnover in the rankings of sales of individual products. Second, we establish some initial results on the implications for shelf-space strategy of physical retailers in such markets.Comment: 10 pages, 3 figure
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