Method and apparatus for controllably heating fluid Patent

Using heat control unit to preheat circulating flui

D-Branes and Fluxes in Supersymmetric Quantum Mechanics

Type 0A string theory in the (2,4k) superconformal minimal model backgrounds, with background ZZ D-branes or R-R fluxes can be formulated non-perturbatively. The branes and fluxes have a description as threshold bound states in an associated one-dimensional quantum mechanics which has a supersymmetric structure, familiar from studies of the generalized KdV system. The relevant bound state wavefunctions in this problem have unusual asymptotics (they are not normalizable in general, and break supersymmetry) which are consistent with the underlying description in terms of open and closed string sectors. The overall organization of the physics is very pleasing: The physics of the closed strings in the background of branes or fluxes is captured by the generalized KdV system and non-perturbative string equations obtained by reduction of that system (the hierarchy of equations found by Dalley, Johnson, Morris and Watterstam). Meanwhile, the bound states wavefunctions, which describe the physics of the ZZ D-brane (or flux) background in interaction with probe FZZT D-branes, are captured by the generalized mKdV system, and non-perturbative string equations obtained by reduction of that system (the Painleve II hierachy found by Periwal and Shevitz in this context).Comment: 41 pages, LaTe

An illicit artisanal fishery for North Pacific white sharks indicates frequent occurrence and high mortality in the Gulf of California

Large sharks shape ecosystems across their geographic ranges and have become a top research and conservation priority. Eastern North Pacific (ENP) white shark (Carcharodon carcharias) aggregations off the United States and Mexico are well described, but their population status is currently uncertain. Population assessments of ENP white sharks are complicated by migrations across international boundaries, vulnerability at aggregation sites, and undetermined mortality levels. While protective legislation exists both in the United States and Mexico, ongoing incidental and unreported catch may undermine assessments and management. Here, access to a clandestine artisanal fishery provides evidence for white shark abundance and mortality in the Gulf of California that has been underestimated by other methods (e.g., satellite telemetry, [by]catch data). Shark size estimates based on tooth measurements suggest abundance of both juvenile and mature sharks in the region, and updated population models indicate the potential for substantial impacts of this fishery on ENP population viability. The data here, fisher-provided information, and anecdotal evidence suggest potentially high abundance at two specific regions, making directed future research efforts feasible in the Gulf. These data demonstrate that cryptic life histories and geopolitical boundaries can still limit fundamental understanding of megafauna distribution, necessitating international cooperation for both research and management

String Theory and Water Waves

We uncover a remarkable role that an infinite hierarchy of non-linear differential equations plays in organizing and connecting certain {hat c}<1 string theories non-perturbatively. We are able to embed the type 0A and 0B (A,A) minimal string theories into this single framework. The string theories arise as special limits of a rich system of equations underpinned by an integrable system known as the dispersive water wave hierarchy. We observe that there are several other string-like limits of the system, and conjecture that some of them are type IIA and IIB (A,D) minimal string backgrounds. We explain how these and several string-like special points arise and are connected. In some cases, the framework endows the theories with a non-perturbative definition for the first time. Notably, we discover that the Painleve IV equation plays a key role in organizing the string theory physics, joining its siblings, Painleve I and II, whose roles have previously been identified in this minimal string context.Comment: 49 pages, 4 figure

An Experimental Investigation into the Effects of Traffic Noise on Distributions of Birds: Avoiding the Phantom Road

Many authors have suggested that the negative effects of roads on animals are largely owing to traffic noise. Although suggestive, most past studies of the effects of road noise on wildlife were conducted in the presence of the other confounding effects of roads, such as visual disturbance, collisions and chemical pollution among others. We present, to our knowledge, the first study to experimentally apply traffic noise to a roadless area at a landscape scale—thus avoiding the other confounding aspects of roads present in past studies. We replicated the sound of a roadway at intervals—alternating 4 days of noise on with 4 days off—during the autumn migratory period using a 0.5 km array of speakers within an established stopover site in southern Idaho. We conducted daily bird surveys along our ‘Phantom Road’ and in a nearby control site. We document over a one-quarter decline in bird abundance and almost complete avoidance by some species between noise-on and noise-off periods along the phantom road and no such effects at control sites—suggesting that traffic noise is a major driver of effects of roads on populations of animals

A social network analysis of actors involved in wild pig (\u3ci\u3eSus scrofa\u3c/i\u3e) management in Missouri

Wild pigs (Sus scrofa) cause significant damage to agriculture and native ecosystems and can transmit diseases to animals and people. Management responses designed to reduce population numbers are needed to mitigate these threats. Identifying networks of key actors, including the ways in which they interact, is valuable for purposes of better understanding opportunities or constraints that generate or impede effective management responses. The goal of our study was to understand the network of organizations, and the personnel working within them, that were active in wild pig management, research, or policy initiatives in Missouri during 2018–2020 by 1) identifying individuals and organizations involved in the network, 2) investigating the attributes of relevant personnel, 3) determining the structural patterns of the network, and 4) examining how the network structure could be optimized to improve communication and collaboration efforts. Results from a social network analysis identified 150 personnel affiliated with 26 organizations actively working on wild pig issues in Missouri. The network was largely homogenous based on respondents\u27 attributes, had low density, and was relatively fragmented, small, decentralized with few ties per node, and separated with few brokers. We emphasize the importance of understanding the strengths and weaknesses of a network\u27s structure in facilitating effective collective action to manage wild pigs

Importance of Flood Irrigation for Foraging Colonial Waterbirds

For a colonial-nesting bird, like the white-faced ibis (Plegadis chihi), the landscape surrounding the breeding colony can be important. White-faced ibis must rely on areas outside their breeding colony for foraging, but this part of their life history has received little attention, and the management of this landscape even less so. To address this knowledge gap, we conducted road-based driving surveys and a randomly selected, spatially balanced sample survey of agricultural fields within a 22-km radius of the 2 largest white-faced ibis breeding colonies in Idaho, USA: Market Lake Wildlife Management Area and Mud Lake Wildlife Management Area. Our study took place in 2012 and the primary objective was to quantify patterns of foraging habitat use of this marsh-nesting species, particularly associations with specific irrigation practices and crop types. We documented the majority of foraging birds in flood-irrigated and wheel-line sprinkler-irrigated agricultural fields (76%) and natural wetlands (13%), which were limited in our study area (3% of land cover). Even though 70% of the agricultural landscape included center pivot sprinkler irrigation, only 11% of foraging observations came from this irrigation type. Most agricultural fields (\u3e85%) used by foraging ibis were flood-irrigated and all had standing water or recent moisture at the time of use. Though ibis used many crop types when foraging in flooded agricultural fields, ibis use of alfalfa (58%) was greater than availability (38%). We also observed distinct distribution patterns around the 2 breeding colonies. Whereas birds foraged in all directions around Mud Lake (~80%) within a 12-km radius from the colony, we observed over half of birds around Market Lake foraging within 12–22 km, and almost exclusively to the south and southeast of the colony, reflecting the distribution of flood-irrigated agriculture in the area. The most common foraging distance (12–22 km) around Market Lake is greater than found in existing literature, suggesting that the foraging habitat is limited within 12 km of the colony and that the birds may need to travel farther to find adequate foraging habitat. Flood-irrigated agriculture and natural wetlands provide foraging habitats for white-faced ibis in eastern Idaho and should be considered in future management and conservation of wetland birds

Isotopic Tracers Suggest Limited Trans-Oceanic Movements and Regional Residency in North Pacific Blue Sharks (Prionace glauca)

Blue sharks (Prionace glauca) are globally distributed, large-bodied pelagic sharks that make extensive migrations throughout their range. In the North Pacific, mark-recapture studies have shown trans-Pacific migrations, but knowledge gaps in migration frequency hinder understanding of regional connectivity and assessments of regional demography for stock assessments. Here, we use oceanographic gradients of stable isotope ratios (i.e., regional isoscapes) to determine exchange rates of blue sharks between the East and West North Pacific Ocean (EPO and WPO). We generated regional δ13C and δ15N distributions for blue sharks from published values in the North Pacific (n = 180; both sexes, juveniles and adults combined). Discriminant analysis suggested low trans-Pacific exchange, categorizing all western (100%) and most eastern (95.3%) blue sharks as resident to their sampling region, with isotopic niche overlap of WPO and EPO highly distinct (0.01–5.6% overlap). Limited trans-Pacific movements suggest that other mechanisms maintain genetic mixing of the North Pacific blue shark population. Potential finer scale movement structure was indicated by isotopic differences in sub-regions of the eastern and western Pacific, though application of mixing models are currently limited by aberrantly low blue shark δ13C values across studies. Our results suggest that blue shark population dynamics may be effectively assessed on a regional basis (i.e., WPO and EPO). We recommend further studies to provide size- and sex-specific movement patterns based on empirical isotopic values with large sample sizes from targeted regions. Strategically applied stable isotope approaches can continue to elucidate migration dynamics of mobile marine predators, complementing traditional approaches to fisheries biology and ecology

Water column structure defines vertical habitat of twelve pelagic predators in the South Atlantic

Quantifying vertical distributions of pelagic predators elucidates pelagic ecosystem structure and informs fisheries management. In the tropical South Atlantic Ocean, the recently designated large-scale marine protected area around Ascension Island hosts diverse pelagic predators for which basin-specific vertical habitat information is minimal or absent. We used pop-up satellite archival tags to analyse vertical habitat use in 12 species (bigeye tuna Thunnus obesus, blue marlin Makaira nigricans, blue shark Prionace glauca, dolphinfish Coryphaena hippurus, Galapagos shark Carcharhinus galapagensis, oceanic whitetip Carcharhinus longimanus, sailfish Istiophorus albicans, silky shark Carcharhinus falciformis, swordfish Xiphias gladius, tiger shark Galeocerdo cuvier, wahoo Acanthocybium solandri, and yellowfin tuna Thunnus albacares) and quantify parameters (temperature, dissolved oxygen, diel cycles, lunar phase) known to constrain vertical movements. Predator depth distributions varied widely, and classification trees grouped predators into four clades: (i) primarily epipelagic; (ii) partial thermocline use; (iii) oscillatory diving with thermocline/sub-thermocline use; and (iv) extensive use of sub-thermocline waters. Vertical habitat differences were linked to thermal physiology and foraging ecology, and species-specific physical constraints from other ocean basins were largely conserved in the South Atlantic. Water column features defined species-specific depth distributions, which can inform fisheries practices and bycatch risk assessments and population estimates

Dispersion force for materials relevant for micro and nanodevices fabrication

The dispersion (van der Waals and Casimir) force between two semi-spaces are calculated using the Lifshitz theory for different materials relevant for micro and nanodevices fabrication, namely, gold, silicon, gallium arsenide, diamond and two types of diamond-like carbon (DLC), silicon carbide, silicon nitride and silicon dioxide. The calculations were performed using recent experimental optical data available in the literature, usually ranging from the far infrared up to the extreme ultraviolet bands of the electromagnetic spectrum. The results are presented in the form of a correction factor to the Casimir force predicted between perfect conductors, for the separation between the semi-spaces varying from 1 nanometre up to 1 micrometre. The relative importance of the contributions to the dispersion force of the optical properties in different spectral ranges is analyzed. The role of the temperature for semiconductors and insulators is also addressed. The results are meant to be useful for the estimation of the impact of the Casimir and van der Waals forces on the operational parameters of micro and nanodevices