Stochastic resonance effects in quantum channels

We provide some examples of quantum channels where the addition of noise is able to enhance the information transmission rate. This may happen for both quantum and classical uses and realizes stochastic resonance effects.Comment: 4 pages, 3 figure

Wetland fish communities above stream regulators with and without fish passage in Lao PDR

We have implemented a multiple lines of evidence approach to assessing the efficacy of fishways in the Houay (small stream) Peung and Houay Souy, Lao PDR. The methods include socio-economic surveys of households, direct observation of fisherman catch, trapping within the fishways, and surveys of fish assemblages in each fishway wetland, along with comparison wetlands that do not have a fishway installed. The in-wetland surveys are designed to be a long-term program and in this presentation I report on the design, monitoring and preliminary results. Whilst there are several differences in the types of fish present in each of the wetlands, there was no statistically significant difference in the CPUE, species richness or the composition of fish assemblages between fishway wetlands and comparison wetlands, regardless of season, during the first two years of our study. This is consistent with previous studies, that found only one or two species are likely to respond in the first few years and it may take 4 or more seasons of operations for major compositional changes in assemblages to be recognised. Our results are consistent with expectations from pre-fishway operations and the monitoring program is well placed to detect changes as the fishways enter full operational mode. We also discuss the implications of high fishing pressure in these wetlands and how this may affect the rate of change and detection of those changes

A cautionary tale about the inhibitory effects of gated culverts on fish passage restoration efforts

Connectivity between river-floodplain habitats has been heavily constrained in many large tropical river systems by the construction of regulators, levees and other physical barriers. Fishways are being constructed to ameliorate the effects of these barriers; but it is important that all aspects of fishway design cater for local target species. We investigated the lateral movement patterns of Lower Mekong Basin fish in Laos, through a fishway that incorporated a series of cones, resting pools, and a culvert with a vertical lift gate. Fish needed to negotiate all of these structures to move from the Mekong to an adjacent wetland. We tested the hypothesis that gated culverts may hamper the effectiveness of fishways, by comparing the abundance and species richness of fish at three locations along the path of the fishway and culvert: (1) the fishway entrance; (2) the fishway exit; and (3) the culvert exit (i.e. immediately upstream of the culvert). There were no marked differences in the total abundance and species richness of fish between the fishway entrance and culvert exit while the river remained at levels where the culvert was only partially inundated. Nevertheless, the abundance and species richness of fish were markedly lower at the culvert exit than at the fishway entrance and exit once the headwater levels rose to where the culvert was completely inundated. These findings indicate that fish were able to ascend the fishway but not the culvert once it became completely submerged, and thus support the hypothesis that gated culverts can hamper the effectiveness of fishways in facilitating the lateral movement of fish in large tropical systems. Fish passage at such installations can be enhanced through optimised operating regimes. Ensuring that headwater levels remain below the culvert ceiling is likely to be the best way to maximise fishway effectiveness

The Origin of Ina: Evidence for Inflated Lava Flows on the Moon

Ina is an enigmatic volcanic feature on the Moon known for its irregularly shaped mounds, the origin of which has been debated since the Apollo Missions. Three main units are observed on the floor of the depression (2.9 km across, < or =64 m deep) located at the summit of a low-shield volcano: irregularly shaped mounds up to 20 m tall, a lower unit 1 to 5 m in relief that surrounds the mounds, and blocky material. Analyses of Lunar Reconnaissance Orbiter Camera images and topography show that features in Ina are morphologically similar to terrestrial inflated lava flows. Comparison of these unusual lunar mounds and possible terrestrial analogs leads us to hypothesize that features in Ina were formed through lava flow inflation processes. While the source of the lava remains unclear, this new model suggests that as the mounds inflated, breakouts along their margins served as sources for surface flows that created the lower morphologic unit. Over time, mass wasting of both morphologic units has exposed fresh surfaces observed in the blocky unit. Ina is different than the terrestrial analogs presented in this study in that the lunar features formed within a depression, no vent sources are observed, and no cracks are observed on the mounds. However, lava flow inflation processes explain many of the morphologic relationships observed in Ina and are proposed to be analogous with inflated lava flows on Earth

New OH Zeeman measurements of magnetic field strengths in molecular clouds

We present the results of a new survey of 23 molecular clouds for the Zeeman effect in OH undertaken with the ATNF Parkes 64-m radio telescope and the NRAO Green Bank 43-m radio telescope. The Zeeman effect was clearly detected in the cloud associated with the HII region RCW 38, with a field strength of 38+/-3 micro-Gauss, and possibly detected in a cloud associated with the HII region RCW 57, with a field strength of -203+/-24 micro-Gauss. The remaining 21 measurements give formal upper limits to the magnetic field strength, with typical 1-sigma sensitivities <20 micro-Gauss. For 22 of the molecular clouds we are also able to determine thecolumn density of the gas in which we have made a sensitive search for the Zeeman effect. We combine these results with previous Zeeman studies of 29 molecular clouds, most of which were compiled by Crutcher (1999), for a comparsion of theoretical models with the data. This comparison implies that if the clouds can be modeled as initially spherical with uniform magnetic fields and densities that evolve to their final equilibrium state assuming flux-freezing then the typical cloud is magnetically supercritical, as was found by Crutcher (1999). If the clouds can be modeled as highly flattened sheets threaded by uniform perpendicular fields, then the typical cloud is approximately magnetically critical, in agreement with Shu et al. (1999), but only if the true values of the field for the non-detections are close to the 3-sigma upper limits. If instead these values are significantly lower (for example, similar to the 1-sigma limits), then the typical cloud is generally magnetically supercritical.Comment: 39 pages, 7 figures. Accepted for publication in Ap

On the Identification of High Mass Star Forming Regions using IRAS: Contamination by Low-Mass Protostars

We present the results of a survey of a small sample (14) of low-mass protostars (L_IR < 10^3 Lsun) for 6.7 GHz methanol maser emission performed using the ATNF Parkes radio telescope. No new masers were discovered. We find that the lower luminosity limit for maser emission is near 10^3 Lsun, by comparison of the sources in our sample with previously detected methanol maser sources. We examine the IRAS properties of our sample and compare them with sources previously observed for methanol maser emission, almost all of which satisfy the Wood & Churchwell criterion for selecting candidate UCHII regions. We find that about half of our sample satisfy this criterion, and in addition almost all of this subgroup have integrated fluxes between 25 and 60 microns that are similar to sources with detectable methanol maser emission. By identifying a number of low-mass protostars in this work and from the literature that satisfy the Wood & Churchwell criterion for candidate UCHII regions, we show conclusively for the first time that the fainter flux end of their sample is contaminated by lower-mass non-ionizing sources, confirming the suggestion by van der Walt and Ramesh & Sridharan.Comment: 8 pages with 2 figures. Accepted by Ap

Implantable Therapeutic Reservoir Systems for Diverse Clinical Applications in Large Animal Models

Regenerative medicine approaches, specifically stem cell technologies, have demonstrated significant potential to treat a diverse array of pathologies. However, such approaches have resulted in a modest clinical benefit, which may be attributed to poor cell retention/survival at the disease site. A delivery system that facilitates regional and repeated delivery to target tissues can provide enhanced clinical efficacy of cell therapies when localized delivery of high doses of cells is required. In this study, a new regenerative reservoir platform (Regenervoir) is described for use in large animal models, with relevance to cardiac, abdominal, and soft tissue pathologies. Regenervoir incorporates multiple novel design features essential for clinical translation, with a focus on scalability, mechanism of delivery, fixation to target tissue, and filling/refilling with a therapeutic cargo, and is demonstrated in an array of clinical applications that are easily translated to human studies. Regenervoir consists of a porous reservoir fabricated from a single material, a flexible thermoplastic polymer, capable of delivering cargo via fill lines to target tissues. A radiopaque shear thinning hydrogel can be delivered to the therapy reservoir and multiple fixation methods (laparoscopic tacks and cyanoacrylate bioadhesive) can be used to secure Regenervoir to target tissues through a minimally invasive approach.In this study, a new regenerative reservoir platform (Regenervoir) is described for use in large animal models that are easily translated to human studies, with relevance to cardiac, abdominal, and soft tissue pathologies. Regenervoir incorporates multiple novel design features essential for clinical translation, with a focus on scalability, mechanism of delivery, fixation, and filling/refilling with a therapeutic cargo.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155890/1/adhm202000305.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155890/2/adhm202000305_am.pd

Capacity building permitting comprehensive monitoring of a severe case of Lassa hemorrhagic fever in Sierra Leone with a positive outcome: Case Report

Lassa fever is a neglected tropical disease with a significant impact on the health care system of endemic West African nations. To date, case reports of Lassa fever have focused on laboratory characterisation of serological, biochemical and molecular aspects of the disease imported by infected individuals from Western Africa to the United States, Canada, Europe, Japan and Israel. Our report presents the first comprehensive real time diagnosis and characterization of a severe, hemorrhagic Lassa fever case in a Sierra Leonean individual admitted to the Kenema Government Hospital Lassa Fever Ward. Fever, malaise, unresponsiveness to anti-malarial and antibiotic drugs, followed by worsening symptoms and onset of haemorrhaging prompted medical officials to suspect Lassa fever. A recombinant Lassa virus protein based diagnostic was employed in diagnosing Lassa fever upon admission. This patient experienced a severe case of Lassa hemorrhagic fever with dysregulation of overall homeostasis, significant liver and renal system involvement, the interplay of pro- and anti-inflammatory cytokines during the course of hospitalization and an eventual successful outcome. These studies provide new insights into the pathophysiology and management of this viral illness and outline the improved infrastructure, research and real-time diagnostic capabilities within LASV endemic areas