Re-entrant ferroelectricity in liquid crystals

The ferroelectric (Sm C$^*$) -- antiferroelectric (Sm C$^*_A$) -- reentrant ferroelectric (re Sm C$^*$) phase temperature sequence was observed for system with competing synclinic - anticlinic interactions. The basic properties of this system are as follows (1) the Sm C$^*$ phase is metastable in temperature range of the Sm C$^*_A$ stability (2) the double inversions of the helix handedness at Sm C$^*$ -- Sm C$^*_A$ and Sm C$^*_A$% -- re-Sm C$^*$ phase transitions were found (3) the threshold electric field that is necessary to induce synclinic ordering in the Sm C$^*_A$ phase decreases near both Sm C$^*_A$ -- Sm C$^*$ and Sm C$^*_A$ -- re-Sm C$^*$ phase boundaries, and it has maximum in the middle of the Sm C$^*_A$ stability region. All these properties are properly described by simple Landau model that accounts for nearest neighboring layer steric interactions and quadrupolar ordering only.Comment: 10 pages, 5 figures, submitted to PR

A Win-Win: Utilizing Human Services Students to Run a Campus Food Pantry

Abstract Recent studies have examined the growing problem of food insecurity among college students in the United States. In recent reports, as many as 30% of all college students are food insecure (CUFBA, 2020). It is imperative that college campuses address this issue, as many students are forced to leave college without completion in order to address financial concerns (Johnson, 2009). Over the last decade, campus-based food pantries have emerged as one means of addressing growing food insecurity among students. However, colleges and universities are facing budget cutbacks and other funding restrictions, creating greater challenges for meeting the needs of financially-struggling students. This article addresses how developing campus food pantries utilizing service-learning, internships and field practicum courses in Human Services programs can assist with addressing this need. By using Human Services students, as well as partnering with local agencies, colleges and universities can address the need for labor and supplies with few to no available state resources, providing a win-win situation for students and colleges

Estimating the Effects Weather, Dry Matter Intake, and Body Weight on Daily Water Intake in Weaned Calves

Water is an essential nutrient and is required for growth, metabolism, lactation, and reproduction. However, water requirements for beef cattle have not been studied extensively since the 1950’s. The genetic potential for beef cattle has changed considerably since then. With the change in genetics, beef producers have observed increases in average daily gain and final body weight. The need for updated water requirements for beef cattle has also been exacerbated by global climate variability, drought conditions, and the need for efficient use of water resources. Given the increased productivity of cattle today relative to those of decades ago, increased water requirements are almost certain. Further research must be conducted to determine how those requirements have changed

Maximum elastic deformations of relativistic stars

We present a method for calculating the maximum elastic quadrupolar deformations of relativistic stars, generalizing the previous Newtonian, Cowling approximation integral given by [G. Ushomirsky et al., Mon. Not. R. Astron. Soc. 319, 902 (2000)]. (We also present a method for Newtonian gravity with no Cowling approximation.) We apply these methods to the m = 2 quadrupoles most relevant for gravitational radiation in three cases: crustal deformations, deformations of crystalline cores of hadron-quark hybrid stars, and deformations of entirely crystalline color superconducting quark stars. In all cases, we find suppressions of the quadrupole due to relativity compared to the Newtonian Cowling approximation, particularly for compact stars. For the crust these suppressions are up to a factor ~6, for hybrid stars they are up to ~4, and for solid quark stars they are at most ~2, with slight enhancements instead for low mass stars. We also explore ranges of masses and equations of state more than in previous work, and find that for some parameters the maximum quadrupoles can still be very large. Even with the relativistic suppressions, we find that 1.4 solar mass stars can sustain crustal quadrupoles of a few times 10^39 g cm^2 for the SLy equation of state or close to 10^40 g cm^2 for equations of state that produce less compact stars. Solid quark stars of 1.4 solar masses can sustain quadrupoles of around 10^44 g cm^2. Hybrid stars typically do not have solid cores at 1.4 solar masses, but the most massive ones (~2 solar masses) can sustain quadrupoles of a few times 10^41 g cm^2 for typical microphysical parameters and a few times 10^42 g cm^2 for extreme ones. All of these quadrupoles assume a breaking strain of 0.1 and can be divided by 10^45 g cm^2 to yield the fiducial "ellipticities" quoted elsewhere.Comment: 21 pages, 11 figures, version accepted by PRD, including the corrected maximum hybrid star quadrupoles (from the erratum to the shear modulus calculation) and the corrected binding energy computatio

Estimating the Effects of Weather, Dry Matter Intake, and Body Weight on Daily Water Intake in Weaned Calves

Objective The purpose of this study was to study the effect of weather, dry matter intake, and body weight on the water requirements of weaned calves and estimating the requirements in a model.Study Description Weaned steers (n=48) were selected to study the effects of the weather, body weight, and dry matter intake on water intake in the winter (n=24) and summer (n=24) months. Calves were provided with ad libitum access to feed and water at the SDSU Cow-Calf Education and Research Facility (CCERF) and measured utilizing an automated feed and water system (Insentec, The Hague, Netherlands). Temperature, humidity, precipitation, wind speed, solar radiation, and air pressure were recorded at a Mesonet automated weather station in Brookings, SD (located 2.4 miles from the SDSU CCERF). Effects of climate data, body weight, and daily dry matter intake on daily water intake will be analyzed utilizing a mixed-effects model

Identification of Genes Associated with Water Restriction Expressed in the Renal Cortex and Hypothalamus in Cattle

The short-term objective of this study is to discover genes associated with water restriction expressed in the renal cortex and hypothalamus in beef calves. The long-term goal is to understand genes and pathways important for thirst response in cattle. This knowledge may lead to discovery of genetic variants associated with water intake. Identification of animals with genetic potential to grow and thrive under drought conditions would be an asset to beef producers and communities which rely on beef production for a large part of their livelihoods. Both selected tissue types are known to be involved in response to hypertonicity (e.g., water restriction or dehydration)

Performance of a BGO PET/CT with Higher Resolution PET Detectors

A new PET detector block has been designed to replace the standard detector of the Discovery ST PET/CT system. The new detector block is the same size as the original, but consists of an 8/spl times/6 (tangential× axial) matrix of crystals rather than the original 6/spl times/6. The new crystal dimensions are 4.7× 6.3× 30 mm/sup 3/ (tangential× axial× radial). Full PET/CT systems have been built with these detectors (Discovery STE). Most other aspects of the system are identical to the standard Discovery ST, with differences including the low energy threshold for 3D imaging (now 425 keV) and front-end electronics. Initial performance evaluation has been done, including NEMA NU2-2001 tests and imaging of the 3D Hoffman brain phantom and a neck phantom with small lesions. The system sensitivity was 1.90 counts/s/kBq in 2D, and 9.35 counts/s/kBq in 3D. Scatter fractions measured for 2D and 3D, respectively, were 18.6% and 34.5%. In 2D, the peak NEC of 89.9 kcps occurred at 47.0 kBq/cc. In 3D, the peak NEC of 74.3 kcps occurred at 8.5 kBq/cc. Spatial resolution (all expressed in mm FWHM) measured in 2D for 1 cm off-axis source 5.06 transaxial, 5.14 axial and for 10 cm source 5.45 radial, 5.86 tangential, and 6.23 axial. In 3D for 1 cm off-axis source 5.13 transaxial, 5.74 axial, and for 10 cm source 5.92 radial, 5.54 tangential, and 6.16 axial. Images of the brain and neck phantom demonstrate some improvement, compared to measurements on a standard Discovery ST

Spatially Resolved Temperature and Water Vapor Concentration Distributions in Supersonic Combustion Facilities by TDLAT

Detailed knowledge of the internal structure of high-enthalpy flows can provide valuable insight to the performance of scramjet combustors. Tunable Diode Laser Absorption Spectroscopy (TDLAS) is often employed to measure temperature and species concentration. However, TDLAS is a path-integrated line-of-sight (LOS) measurement, and thus does not produce spatially resolved distributions. Tunable Diode Laser Absorption Tomography (TDLAT) is a non-intrusive measurement technique for determining two-dimensional spatially resolved distributions of temperature and species concentration in high enthalpy flows. TDLAT combines TDLAS with tomographic image reconstruction. More than 2500 separate line-of-sight TDLAS measurements are analyzed in order to produce highly resolved temperature and species concentration distributions. Measurements have been collected at the University of Virginia's Supersonic Combustion Facility (UVaSCF) as well as at the NASA Langley Direct-Connect Supersonic Combustion Test Facility (DCSCTF). Due to the UVaSCF s unique electrical heating and ability for vitiate addition, measurements collected at the UVaSCF are presented as a calibration of the technique. Measurements collected at the DCSCTF required significant modifications to system hardware and software designs due to its larger measurement area and shorter test duration. Tomographic temperature and water vapor concentration distributions are presented from experimentation on the UVaSCF operating at a high temperature non-reacting case for water vitiation level of 12%. Initial LOS measurements from the NASA Langley DCSCTF operating at an equivalence ratio of 0.5 are also presented. Results show the capability of TDLAT to adapt to several experimental setups and test parameters

Poorly Crystalline, Iron-Bearing Aluminosilicates and Their Importance on Mars

Martian rocks and sediments contain weathering products including evaporite salts and clay minerals that only form as a result of interaction between rocks and water [1-6]. These weathering products are key to studying the history of water on Mars because their type, abundance and location provide clues to past conditions on the surface of the planet, as well as to the possible location of present-day reservoirs of water. Weathering of terrestrial volcanic rocks similar to those on Mars produces nano-sized, variably hydrated aluminosilicate and iron oxide minerals [7-10] including allophane, imogolite, halloysite, hisingerite, and ferrihydrite. The nanoaluminosilicates can contain isomorphically substituted Fe, which affects their spectral and physical properties. Detection and quantification of such minerals in natural environments on earth is difficult due to their variable chemical composition and lack of long-range crystalline order [9, 11, 12]. Despite the difficulty in characterizing these materials, they are common on Earth, and data from orbital remote sensing and rover-based instruments suggest that they are also present on Mars [9, 10, 13-17]. Their accurate detection and quantification require a better understanding of how composition affects their spectral properties. We present here the results of XAFS spectroscopy; these results will be corroborated with planned Mossbauer and reflectance spectroscopy

Factors associated with the decision to investigate child protective services referrals: a systematic review

Background: Limited resources for child protection create challenging decision situations for child protective services (CPS) workers at the point of intake. A body of research has examined the factors associated with worker decisions and processes using a variety of methodological approaches to gain knowledge on decision-making. However, few attempts have been made to systematically review this literature. Objective: As part of a larger project on decision-making at intake, this systematic review addressed the question of the factors associated with worker decisions to investigate alleged maltreatment referrals. Methods: Quantitative studies that examined factors associated with screening decisions in CPS practice settings were included in the review. Database and other search methods were used to identify research published in English over a 35-year period (1980-2015). Findings: Of 1,147 identified sources, 18 studies were selected for full data extraction. The studies were conducted in the U.S., Canada, and Sweden and varied in methodological quality. Most studies examined case factors with few studies examining other domains. Conclusions: To inform CPS policy and practice, additional research is needed to examine the relationships between decision-making factors and case outcomes. Greater attention needs to be given to the organizational and external factors that influence decision-making