Design and operation of LongBo: a 2 m long drift liquid argon TPC

In this paper, we report on the design and operation of the LongBo time projection chamber in the Liquid Argon Purity Demonstrator cryostat. This chamber features a 2 m long drift distance. We measure the electron drift lifetime in the liquid argon using cosmic ray muons and the lifetime is at least 14 ms at 95\% confidence level. LongBo is equipped with preamplifiers mounted on the detector in the liquid argon. Of the 144 channels, 128 channels were readout by preamplifiers made with discrete circuitry and 16 channels were readout by ASIC preamplifiers. For the discrete channels, we measure a signal-to-noise (S/N) ratio of 30 at a drift field of 350 V/cm. The measured S/N ratio for the ASIC channels was 1.4 times larger than that measured for the discrete channels.Comment: 19 pages, 17 figure

Cassava Waste Management and Biogas Generation Potential in Selected Local Government Areas in Ogun State, Nigeria

Agricultural products such as cassava produce huge amounts of waste when processed into consumable goods. The waste generated is generally considered to contribute largely to environmental pollution. This study therefore investigates the waste management practice that is adopted by cassava processors in Ogun State, Nigeria. Five local government areas (LGAs) dominant in processing cassava were selected for the study on the basis of spatial location distribution, landmass, and population. The survey involved the use of structured questionnaires administered to cassava processors of the selected LGAs. The Statistical Package for Social Sciences (SPSS) software application and descriptive statistics were used for data analysis. Results of the analysis show that the majority (70%) of the cassava processors are females. Cassava peel constitutes 10% of the waste produced, of which 91% is heaped at refuse dumps in most communities. Results also reveal that 86.3% of cassava residues are used for animal feeds. Other findings show that the peels, when dried, are used as biofuel for cooking and there is a significant potential for biogas production. From the data captured from respondents during the study, most processors are willing to pay for an improved waste management system. The study therefore recommends the proper waste management of cassava waste to minimize environmental pollution

Strontium Carbonate: As an Efficient, Environmentally free catalyst for the synthesis of 2-Aryl Benzoxazole derivatives

A Highly Efficient and environmentally benign method has been developed for the synthesis of 2- Aryl benzoxazoles from 2-aminophenol and substituted aldehydes in presence of nanocrystalline strontium carbonate catalyst at room temperature and solvent free conditions

Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of $^{238}$U$_{e}$~$<$1.6~mBq/kg, $^{238}$U$_{l}$~$<$0.09~mBq/kg, $^{232}$Th$_{e}$~$=0.28\pm 0.03$~mBq/kg, $^{232}$Th$_{l}$~$=0.25\pm 0.02$~mBq/kg, $^{40}$K~$<$0.54~mBq/kg, and $^{60}$Co~$<$0.02~mBq/kg (68\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of $0.160\pm0.001$(stat)$\pm0.030$(sys) counts.Comment: 13 pages, 3 figures, accepted for publication in Astroparticle Physic

Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF

The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described

A systematic analysis of host factors reveals a Med23-interferon-λ regulatory axis against herpes simplex virus type 1 replication

Herpes simplex virus type 1 (HSV-1) is a neurotropic virus causing vesicular oral or genital skin lesions, meningitis and other diseases particularly harmful in immunocompromised individuals. To comprehensively investigate the complex interaction between HSV-1 and its host we combined two genome-scale screens for host factors (HFs) involved in virus replication. A yeast two-hybrid screen for protein interactions and a RNA interference (RNAi) screen with a druggable genome small interfering RNA (siRNA) library confirmed existing and identified novel HFs which functionally influence HSV-1 infection. Bioinformatic analyses found the 358 HFs were enriched for several pathways and multi-protein complexes. Of particular interest was the identification of Med23 as a strongly anti-viral component of the largely pro-viral Mediator complex, which links specific transcription factors to RNA polymerase II. The anti-viral effect of Med23 on HSV-1 replication was confirmed in gain-of-function gene overexpression experiments, and this inhibitory effect was specific to HSV-1, as a range of other viruses including Vaccinia virus and Semliki Forest virus were unaffected by Med23 depletion. We found Med23 significantly upregulated expression of the type III interferon family (IFN-λ) at the mRNA and protein level by directly interacting with the transcription factor IRF7. The synergistic effect of Med23 and IRF7 on IFN-λ induction suggests this is the major transcription factor for IFN-λ expression. Genotypic analysis of patients suffering recurrent orofacial HSV-1 outbreaks, previously shown to be deficient in IFN-λ secretion, found a significant correlation with a single nucleotide polymorphism in the IFN-λ3 (IL28b) promoter strongly linked to Hepatitis C disease and treatment outcome. This paper describes a link between Med23 and IFN-λ, provides evidence for the crucial role of IFN-λ in HSV-1 immune control, and highlights the power of integrative genome-scale approaches to identify HFs critical for disease progression and outcome

SPATIAL DISTRIBUTION AND HEALTH RISK ASSESSMENT OF HEAVY METALS IN URBAN PARKS AND GARDENS SOILS IN LAGOS STATE, NIGERIA

Distribution and health risk assessment of heavy metals in urban parks and gardens Gani Fawehinmi Park, Ojota, (GFP), Oshodi Heritage Park Oshodi (OHP), Ikorodu/Ipado Garden (IIG), MKO Abiola Gardens, Ojota (MKO), and MOE Garden, Alausa (MOE) soils in Lagos Metropolis, Nigeria were examined using Index of Geo-accumulation (Igeo), Potential Ecological Risk Index (RI) and health risk model. Urban parks and gardens soils were substantially polluted by Cu and Pb due closeness to highways where heavy metals emitted from motor vehicles are deposited. &nbsp;Geoaccumulation index (Igeo) values for Pb were 10.616, 10.060, 9.027, 8.862 and 8.665 for GFP, OHP, IIG, MKO and MOE respectively. RI values for all the sites showed high pollution as they were all above 200. Health risk assessment revealed that children who visit the urban parks and garden in Lagos State are more exposed to cancer risk from Pb especially through ingestion. Results from this study provided valuable information on the pollution levels of urban parks in Lagos, Nigeria as a result of traffic related emissions and calls for proper monitoring of anthropogenic activities in the metropolis and reduce the human health impacts. The planting of hedge plants and erection of low walls could serve as shield against traffic pollution for the roadside parks &nbsp; &nbsp; &nbsp

Summary of the second workshop on liquid argon time projection chamber research and development in the United States

The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the current efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world

Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of $^{238}$U$_{e}$~$<$1.6~mBq/kg, $^{238}$U$_{l}$~$<$0.09~mBq/kg, $^{232}$Th$_{e}$~$=0.28\pm 0.03$~mBq/kg, $^{232}$Th$_{l}$~$=0.25\pm 0.02$~mBq/kg, $^{40}$K~$<$0.54~mBq/kg, and $^{60}$Co~$<$0.02~mBq/kg (68\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of $0.160\pm0.001$(stat)$\pm0.030$(sys) counts