Scattering by PT-symmetric non-local potentials

A general formalism is worked out for the description of one-dimensional scattering by non-local separable potentials and constraints on transmission and reflection coefficients are derived in the cases of P, T, or PT invariance of the Hamiltonian. The case of a solvable Yamaguchi potential is discussed in detail.Comment: 11 page

Innate and learned preferences for sweet taste during childhood

Purpose of review: In nature, carbohydrates are a source of energy often equated with sweetness, the detection of which is associated with powerful hedonic appeal. Intakes of processed carbohydrates in the form of added sugars and sugar-sweetened beverages have risen consistently among all age groups over the last two decades. In this review, we describe the biological underpinnings that drive the consumption of sweet-tasting foods among pediatric populations. Recent findings: Scientific literature suggests that children\u27s liking for all that is sweet is not solely a product of modern-day technology and advertising but reflects their basic biology. In fact, heightened preference for sweet-tasting foods and beverages during childhood is universal and evident among infants and children around the world. The liking for sweet tastes during development may have ensured the acceptance of sweet-tasting foods, such as mother\u27s milk and fruits. Moreover, recent research suggests that liking for sweets may be further promoted by the pain-reducing properties of sugars

An experimental approach to study individual differences in infants\u27 intake and satiation behaviors during bottle-feeding

Background: As a group, bottle-fed infants are at higher risk for rapid weight gain compared with breast-fed infants. However, little is known about individual differences in feeding behaviors of bottle-feeding infants, as well as maternal and infant characteristics associated with bottle-feeding outcomes. Methods: We conducted a 2-day, within-subject study of 21 formula-feeding dyads; the within-subject factor was feeding condition: mother-led (ML; mothers were given the instruction to feed their infants as they typically would) vs. infant-led (IL; the experimenter ensured feeding began when infants signaled hunger and ended when they rejected the bottle on three consecutive occasions). Intake was determined by bottle weight; feedings were video-recorded and later analyzed to determine feeding duration and types of satiation behaviors displayed. Percent difference scores were calculated for each outcome as [((ML – IL)/IL) × 100] to standardize differences among dyads. Mothers completed questionnaires of feeding styles and infant temperament. Results: On average, infants consumed ∼42% more formula during the ML- than IL-condition (p = 0.03). However, notable variation existed in difference scores for intake (range = −52.8% to 268.9%; higher scores reflect greater intake during ML than IL). Stepwise regression illustrated that greater intakes during the ML-condition were predicted by the combination of: (1) higher infant age; (2) lower levels of infant rhythmicity and adaptability; (3) higher levels of infant positive mood; and (4) lower levels of maternal restrictive and responsive feeding styles. Conclusions: This objective, experimental approach illustrated that variation in bottle-feeding outcomes is associated with characteristics of both members of the dyad

Residential summer camp: a new venue for nutrition education and physical activity promotion

Background Millions of children attend residential summer camps each year. However, few studies have examined the potential of camps for obesity prevention efforts. Research in the domain of positive youth development has shown that camp programs as short as one week have both short- and long-term positive effects on self-esteem, self-efficacy and other youth outcomes. The objective of the present study was to highlight the potential of resident camps as promising venues for the promotion of healthy eating and physical activity behaviors in the children who attend. Methods Data for this study came from the American Camp Association 2007 Emerging Issues Survey. This survey assessed camp professionals’ perspectives on a diverse array of issues, including the healthy eating and physical activity of children. Data analysis focused on responses from 247 camp professionals whose camps offered resident camp programs. Results Descriptive and Chi-square statistics were calculated. Ninety-two percent of camp professionals reported that the healthy eating and physical activity of campers was an “important” or “very important” issue for camps. The majority of camps reported offering vegetarian options, healthy snacks and salad bars, and allergen-free options. Additionally, 86% of camp professionals indicated that they had implemented one or more strategies to address concerns related to the unhealthy eating behaviors of children, with top strategies including increasing the availability of fruits and vegetables, increasing the availability of healthy drink options, and improving the nutritional quality of menus. Fewer camp professionals (50%) indicated they had implemented strategies to increase children’s physical activity levels, but many professionals indicated that their camp programs were inherently active and additional strategies to promote physical activity were not necessary. Associations were found between camp affiliation and food options available to campers. Conclusions The majority of camp professionals believe the healthy eating and physical activity of children are important issues for camps and have implemented strategies to address these issues. An important question for future research is to examine whether these strategies are effective in promoting healthy eating and physical activity behaviors in children, as well as ways that camp programs could be improved

Real rank boundaries and loci of forms

In this article we study forbidden loci and typical ranks of forms with respect to the embeddings of $\mathbb P^1\times \mathbb P^1$ given by the line bundles $(2,2d)$. We introduce the Ranestad-Schreyer locus corresponding to supports of non-reduced apolar schemes. We show that, in those cases, this is contained in the forbidden locus. Furthermore, for these embeddings, we give a component of the real rank boundary, the hypersurface dividing the minimal typical rank from higher ones. These results generalize to a class of embeddings of $\mathbb P^n\times \mathbb P^1$. Finally, in connection with real rank boundaries, we give a new interpretation of the $2\times n \times n$ hyperdeterminant.Comment: 17 p

Spectroscopy and Imaging Performance of the Liquid Xenon Gamma-Ray Imaging Telescope (LXeGRIT)

LXeGRIT is a balloon-borne Compton telescope based on a liquid xenon time projection chamber (LXeTPC) for imaging cosmic \g-rays in the energy band of 0.2-20 MeV. The detector, with 400 cm$^2$ area and 7 cm drift gap, is filled with high purity LXe. Both ionization and scintillation light signals are detected to measure the energy deposits and the three spatial coordinates of individual \g -ray interactions within the sensitive volume. The TPC has been characterized with repeated measurements of its spectral and Compton imaging response to \g -rays from radioactive sources such as \na, \cs, \yt and Am-Be. The detector shows a linear response to \g -rays in the energy range 511 keV -4.4 MeV, with an energy resolution (FWHM) of \Delta E/E=8.8% \: \sqrt{1\MeV /E}. Compton imaging of \yt \g -ray events with two detected interactions is consistent with an angular resolution of $\sim$ 3 degrees (RMS) at 1.8 MeV.Comment: To appear in: Hard X-Ray, Gamma-Ray and Neutron Detector Physics XI, 2000; Proc. SPIE, vol. 4140; K.A. Flanagan & O.H. Siegmund, ed

\u27I\u27m not a druggie, I\u27m just a diabetic\u27: a qualitative study of stigma from the perspective of adults with type 1 diabetes

While health-related stigma has been the subject of considerable research in other conditions (eg, HIV/AIDS, obesity), it has not received substantial attention in diabetes. Our aim was to explore perceptions and experiences of diabetes-related stigma from the perspective of adults with type 1 diabetes mellitus (T1DM)

Operation of a LAr-TPC equipped with a multilayer LEM charge readout

A novel detector for the ionization signal in a single phase LAr-TPC, based on the adoption of a multilayer Large Electron Multiplier (LEM) replacing the traditional anodic wire arrays, has been experimented in the ICARINO test facility at the INFN Laboratories in Legnaro. Cosmic muon tracks were detected allowing the measurement of energy deposition and a first determination of the signal to noise ratio. The analysis of the recorded events demonstrated the 3D reconstruction capability of ionizing events in this device in liquid Argon, collecting a fraction of about 90% of the ionization signal with signal to noise ratio similar to that measured with more traditional wire chambersComment: 9 pages, 7 Figure

Associations between Bottle-feeding Intensity and Maternal Encouragement of Bottle-emptying

Objective: To explore longitudinal associations between bottle-feeding and maternal encouragement of infant bottle-emptying during the first 6 months of infancy. Design: Mothers completed questionnaires during the third trimester of pregnancy, then monthly during the first 6 months postpartum. Questionnaires assessed family demographics, maternal and infant weight status, infant feeding patterns and maternal encouragement of infant bottle-emptying. Setting: The Infant Feeding Practices Study 2, conducted by the US Centers for Disease Control and Prevention and the Food and Drug Administration. Subjects: Mothers (n 1776). Results: Repeated-measures regression was used to explore associations between bottle-feeding intensity (BFI; defined as the percentage of daily feedings that were from a bottle) and encouragement of bottle-emptying. Mothers who reported consistently high or consistently low BFI also exhibited consistently higher or lower frequency of encouraging their infants to empty the bottle (respectively) across the first 6 months of infancy, whereas mothers who reported increases in their BFI also exhibited concomitant increases in the frequency to which they encouraged their infants to finish the bottle. More frequent encouragement of bottle-emptying was also associated with feeding expressed breast milk (P\u3c0·001), and lower parity (P=0·01), pre-pregnancy BMI (P=0·002) and infant birth weight (P=0·001). Conclusions: More frequent use of bottles for infant feeding was significantly associated with more frequent encouragement of bottle-emptying. Further research using causal designs is needed to better understand whether the use of bottles promotes this controlling feeding practice or whether mothers with more controlling feeding practices opt to bottle-feed