Picosecond timing of Microwave Cherenkov Impulses from High-Energy Particle Showers Using Dielectric-loaded Waveguides

We report on the first measurements of coherent microwave impulses from high-energy particle-induced electromagnetic showers generated via the Askaryan effect in a dielectric-loaded waveguide. Bunches of 12.16 GeV electrons with total bunch energy of $\sim 10^3-10^4$ GeV were pre-showered in tungsten, and then measured with WR-51 rectangular (12.6 mm by 6.3 mm) waveguide elements loaded with solid alumina ($Al_2 O_3$) bars. In the 5-8 GHz $TE_{10}$ single-mode band determined by the presence of the dielectric in the waveguide, we observed band-limited microwave impulses with amplitude proportional to bunch energy. Signals in different waveguide elements measuring the same shower were used to estimate relative time differences with 2.3 picosecond precision. These measurements establish a basis for using arrays of alumina-loaded waveguide elements, with exceptional radiation hardness, as very high precision timing planes for high-energy physics detectors.Comment: 16 pages, 15 figure

Oral dosing for antenatal corticosteroids in the Rhesus macaque.

Antenatal corticosteroids (ACS) are standard of care for women at risk of preterm delivery, although choice of drug, dose or route have not been systematically evaluated. Further, ACS are infrequently used in low resource environments where most of the mortality from prematurity occurs. We report proof of principle experiments to test betamethasone-phosphate (Beta-P) or dexamethasone-phosphate (Dex-P) given orally in comparison to the clinical treatment with the intramuscular combination drug beta-phosphate plus beta-acetate in a Rhesus Macaque model. First, we performed pharmacokinetic studies in non-pregnant monkeys to compare blood levels of the steroids using oral dosing with Beta-P, Dex-P and an effective maternal intramuscular dose of the beta-acetate component of the clinical treatment. We then evaluated maternal and fetal blood steroid levels with limited fetal sampling under ultrasound guidance in pregnant macaques. We found that oral Beta is more slowly cleared from plasma than oral Dex. The blood levels of both drugs were lower in maternal plasma of pregnant than in non-pregnant macaques. Using the pharmacokinetic data, we treated groups of 6-8 pregnant monkeys with oral Beta-P, oral Dex-P, or the maternal intramuscular clinical treatment and saline controls and measured pressure-volume curves to assess corticosteroid effects on lung maturation at 5d. Oral Beta-P improved the pressure-volume curves similarly to the clinical treatment. Oral Dex-P gave more variable and nonsignificant responses. We then compared gene expression in the fetal lung, liver and hippocampus between oral Beta-P and the clinical treatment by RNA-sequencing. The transcriptomes were largely similar with small gene expression differences in the lung and liver, and no differences in the hippocampus between the groups. As proof of principle, ACS therapy can be effective using inexpensive and widely available oral drugs. Clinical dosing strategies must carefully consider the pharmacokinetics of oral Beta-P or Dex-P to minimize fetal exposure while achieving the desired treatment responses

Surfactant phosphatidylcholine half-life and pool size measurements in premature baboons developing bronchopulmonary dysplasia

Because minimal information is available about surfactant metabolism in bronchopulmonary dysplasia, we measured half-lives and pool sizes of surfactant phosphatidylcholine in very preterm baboons recovering from respiratory distress syndrome and developing bronchopulmonary dysplasia, using stable isotopes, radioactive isotopes, and direct pool size measurements. Eight ventilated premature baboons received (2)H-DPPC (dipalmitoyl phosphatidylcholine) on d 5 of life, and radioactive (14)C-DPPC with a treatment dose of surfactant on d 8. After 14 d, lung pool sizes of saturated phosphatidylcholine were measured. Half-life of (2)H-DPPC (d 5) in tracheal aspirates was 28 +/- 4 h (mean +/- SEM). Half-life of radioactive DPPC (d 8) was 35 +/- 4 h. Saturated phosphatidylcholine pool size measured with stable isotopes on d 5 was 129 +/- 14 micro mol/kg, and 123 +/- 11 micro mol/kg on d 14 at autopsy. Half-lives were comparable to those obtained at d 0 and d 6 in our previous baboon studies. We conclude that surfactant metabolism does not change during the early development of bronchopulmonary dysplasia, more specifically, the metabolism of exogenous surfactant on d 8 is similar to that on the day of birth. Surfactant pool size is low at birth, increases after surfactant therapy, and is kept constant during the first 2 wk of life by endogenous surfactant synthesis. Measurements with stable isotopes are comparable to measurements with radioactive tracers and measurements at autopsy

OPT3 is a component of the iron-signaling network between leaves and roots and misregulation of OPT3 leads to an over-accumulation of cadmium in seeds.

Plants and seeds are the main dietary sources of zinc, iron, manganese, and copper, but are also the main entry point for toxic elements such as cadmium into the food chain. We report here that an Arabidopsis oligopeptide transporter mutant, opt3-2, over-accumulates cadmium (Cd) in seeds and roots but, unexpectedly, under-accumulates Cd in leaves. The cadmium distribution in opt3-2 differs from iron, zinc, and manganese, suggesting a metal-specific mechanism for metal partitioning within the plant. The opt3-2 mutant constitutively up-regulates the Fe/Zn/Cd transporter IRT1 and FRO2 in roots, indicative of an iron-deficiency response. No genetic mutants that impair the shoot-to-root signaling of iron status in leaves have been identified. Interestingly, shoot-specific expression of OPT3 rescues the Cd sensitivity and complements the aberrant expression of IRT1 in opt3-2 roots, suggesting that OPT3 is required to relay the iron status from leaves to roots. OPT3 expression was found in the vasculature with preferential expression in the phloem at the plasma membrane. Using radioisotope experiments, we found that mobilization of Fe from leaves is severely affected in opt3-2, suggesting that Fe mobilization out of leaves is required for proper trace-metal homeostasis. When expressed in yeast, OPT3 does not localize to the plasma membrane, precluding the identification of the OPT3 substrate. Our in planta results show that OPT3 is important for leaf phloem-loading of iron and plays a key role regulating Fe, Zn, and Cd distribution within the plant. Furthermore, ferric chelate reductase activity analyses provide evidence that iron is not the sole signal transferred from leaves to roots in leaf iron status signaling

Automated Certification of Authorisation Policy Resistance

Attribute-based Access Control (ABAC) extends traditional Access Control by considering an access request as a set of pairs attribute name-value, making it particularly useful in the context of open and distributed systems, where security relevant information can be collected from different sources. However, ABAC enables attribute hiding attacks, allowing an attacker to gain some access by withholding information. In this paper, we first introduce the notion of policy resistance to attribute hiding attacks. We then propose the tool ATRAP (Automatic Term Rewriting for Authorisation Policies), based on the recent formal ABAC language PTaCL, which first automatically searches for resistance counter-examples using Maude, and then automatically searches for an Isabelle proof of resistance. We illustrate our approach with two simple examples of policies and propose an evaluation of ATRAP performances.Comment: 20 pages, 4 figures, version including proofs of the paper that will be presented at ESORICS 201

Electrocardiographic Left Ventricular Hypertrophy Among Gambian Diabetes Mellitus Patients

Background: The global prevalence of diabetes and its complications is increasing worldwide. Its role in coronary heart disease has been linked with the presence of left ventricular hypertrophy (LVH). The present study aims to determine the prevalence of electrocardiographic left ventricular hypertrophy (ECG-LVH) in adult diabetic subjects, its epidemiological and clinical correlates.Methods: A descriptive cross-sectional study involving 534 patients was conducted at the Edward Francis Small Teaching Hospital (formerly Royal Victoria Teaching Hospital), The Gambia. Four hundred and forty patients were included using a standard questionnaire. Anthropometry, laboratory investigations and electrocardiogram were carried out. We used the Lewis, Cornell, and Sokolow-Lyon Voltage criteria to define ECG-LVH. MinitabTM statistical software version 13.20 was used for analysis.Results: 146 (35.2%) patients had ECG-LVH using all 3 criteria and this prevalence was higher among women being 116 (79.5%). A generally high prevalence of overweight (155/37.4%) and obesity (119/28.6%) was observed among study participants, and both clinic-day systolic and diastolic blood pressure (BP) were significantly higher in those with ECG-LVH. Poor diabetes control was observed in both groups.Conclusion: There was a high prevalence of ECGLVH and it is especially so with combining multiple criteria, hence the need for screening. Clinic-day hypertension was associated with ECG-LVH hence the need for diagnosing and aggressive treatment of hypertension in patients with diabetes mellitus.Keywords: Diabetes mellitus, ECG-LVH, The Gambia, voltage criteri

Low-dose betamethasone-acetate for fetal lung maturation in preterm sheep

BackgroundAntenatal steroids are standard of care for women who are at risk of preterm delivery; however, antenatal steroid dosing and formulation have not been evaluated adequately. The standard clinical 2-dose treatment with betamethasone-acetate+betamethasone-phosphate is more effective than 2 doses of betamethasone-phosphate for the induction of lung maturation in preterm fetal sheep. We hypothesized that the slowly released betamethasone-acetate component induces similar lung maturation to betamethasone-phosphate+betamethasone-acetate with decreased dose and fetal exposure.ObjectiveThe purpose of this study was to investigate pharmacokinetics and fetal lung maturation of antenatal betamethasone-acetate in preterm fetal sheep.Study designGroups of 10 singleton-pregnant ewes received 1 or 2 intramuscular doses 24 hours apart of 0.25 mg/kg/dose of betamethasone-phosphate+betamethasone-acetate (the standard of care dose) or 1 intramuscular dose of 0.5 mg/kg, 0.25 mg/kg, or 0.125 mg/kg of betamethasone-acetate. Fetuses were delivered 48 hours after the first injection at 122 days of gestation (80% of term) and ventilated for 30 minutes, with ventilator settings, compliance, vital signs, and blood gas measurements recorded every 10 minutes. After ventilation, we measured static lung pressure-volume curves and sampled the lungs for messenger RNA measurements. Other groups of pregnant ewes and fetuses were catheterized and treated with intramuscular injections of betamethasone-phosphate 0.125 mg/kg, betamethasone-acetate 0.125 mg/kg, or betamethasone-acetate 0.5 mg/kg. Maternal and fetal betamethasone concentrations in plasma were measured for 24 hours.ResultsAll betamethasone-treated groups had increased messenger RNA expression of surfactant proteins A, B, and C, ATP-binding cassette subfamily A member 3, and aquaporin-5 compared with control animals. Treatment with 1 dose of intramuscular betamethasone-acetate 0.125mg/kg improved dynamic and static lung compliance, gas exchange, and ventilation efficiency similarly to the standard treatment of 2 doses of 0.25 m/kg of betamethasone-acetate+betamethasone-phosphate. Betamethasone-acetate 0.125 mg/kg resulted in lower maternal and fetal peak plasma concentrations and decreased fetal exposure to betamethasone compared with betamethasone-phosphate 0.125 mg/kg.ConclusionA single dose of betamethasone-acetate results in similar fetal lung maturation as the 2-dose clinical formulation of betamethasone-phosphate+betamethasone-acetate with decreased fetal exposure to betamethasone. A lower dose of betamethasone-acetate may be an effective alternative to induce fetal lung maturation with less risk to the fetus

Evaluation of a 2-1-1 Telephone Navigation Program to increase Cancer Control Behaviors: Results From a Randomized Controlled Trial

PURPOSE: to evaluate the effectiveness of a telephone navigation intervention for increasing use of cancer control services among underserved 2-1-1 callers. DESIGN: Randomized controlled trial. SETTING: 2-1-1 call centers in Houston and Weslaco, Texas (located in the Rio Grande Valley near the Mexican border). PARTICIPANTS: 2-1-1 callers in need of Pap test, mammography, colorectal cancer screening, smoking cessation counseling, and/or HPV vaccination for a daughter (n = 1,554). A majority were low-income and described themselves as Black or Hispanic. INTERVENTION: Participants were randomly assigned to receive either a cancer control referral for the needed service(s) with telephone navigation from a trained cancer control navigator (n = 995) or a referral only (n = 559). MEASURES: Uptake of each individual service and any needed service. ANALYSIS: Assessed uptake in both groups using bivariate chi-square analyses and multivariable logistic regression analyses, adjusted for sociodemographic covariates. Both per-protocol and intent-to-treat approaches were used. RESULTS: Both interventions increased cancer control behaviors. Referral with navigation intervention resulted in significantly greater completion of any needed service (OR = 1.38; p = .042), Pap test (OR = 1.56; p = .023), and smoking cessation counseling (OR = 2.66; p = .044), than referral-only condition. Other outcomes showed the same trend although the difference was not statistically significant: mammography (OR = 1.53; p = .106); colorectal cancer screening (OR = 1.80; p = .095); and HPV vaccination of a daughter (OR = 1.61; p = .331). CONCLUSION: Adding cancer control referrals and navigation to an informational service like the 2-1-1 program can increase overall participation in cancer control services

Cancer control needs of 2-1-1 callers in Missouri, North Carolina, Texas, and Washington

Innovative interventions are needed to connect underserved populations to cancer control services. With data from Missouri, North Carolina, Texas, and Washington this study a) estimated the cancer control needs of callers to 2-1-1, an information and referral system used by underserved populations, b) compared rates of need to state and national data, and c) examined receptiveness to needed referrals. From October 2009 to March 2010 callers’ (N = 1408) cancer control needs were assessed in six areas: breast, cervical, and colorectal cancer screening, HPV vaccination, smoking, and smoke-free homes using Behavioral Risk Factor Surveillance System (BRFSS) survey items. Standardized estimates were compared to state and national rates. Nearly 70% of the sample had at least one cancer control need. Needs were greater for 2-1-1 callers compared to state and national rates, and callers were receptive to referrals. 2-1-1 could potentially be a key partner in efforts to reduce cancer disparities