The M4 Core Project with HST - IV. Internal Kinematics from Accurate Radial Velocities of 2771 Cluster Members

We present a detailed study of the internal kinematics of the Galactic Globular Cluster M 4 (NGC 6121), by deriving the radial velocities from 7250 spectra for 2771 stars distributed from the upper part of the Red Giant Branch down to the Main Sequence. We describe new approaches to determine the wavelength solution from day-time calibrations and to determine the radial velocity drifts that can occur between calibration and science observations when observing with the GIRAFFE spectrograph at VLT. Two techniques to determine the radial velocity are compared, after a qualitative description of their advantages with respect to other commonly used algorithm, and a new approach to remove the sky contribution from the spectra obtained with fibre-fed spectrograph and further improve the radial velocity precision is presented. The average radial velocity of the cluster is $\langle v \rangle = 71.08 \pm 0.08$ km s$^{-1}$ with an average dispersion of $\mu_{v_c} = 3.97$ km s$^{-1}$. Using the same dataset and the same statistical approach of previous analyses, 20 additional binary candidates are found, for a total of 87 candidates. A new determination of the internal radial velocity dispersion as a function of cluster distance is presented, resulting in a dispersion of $4.5$ km s$^{-1}$ within 2$^{\prime}$ from the center of cluster and steadily decreasing outward. We statistically confirm the small amplitude of the cluster rotation, as suggested in the past by several authors. This new analysis represents a significant improvement with respect to previous results in literature and provides a fundamental observational input for the modeling of the cluster dynamics.Comment: 17 pages, 17 figures. Accepted for publication in MNRAS on September 15, 201

TASTE IV. Refining ephemeris and orbital parameters for HAT-P-20b and WASP-1b

We present four new light curves of transiting exoplanets WASP-1b and HAT-P-20b, observed within the TASTE (The Asiago Search for Transit timing variations of Exoplanets) project. We re-analyzed light curves from the literature in a homogeneous way, calculating a refined ephemeris and orbital-physical parameters for both objects. WASP-1b does not show any significant Transit Timing Variation signal at the 120 s-level. As for HAT-P-20b, we detected a deviation from our re-estimated linear ephemeris that could be ascribed to the presence of a perturber or, more probably, to a previously unnoticed high level of stellar activity. The rotational period of HAT-P-20 A we obtained from archival data (P_rot ~ 14.5 days), combined with its optical variability and strong emission of CaII H&K lines, is consistent with a young stellar age (< 1 Gyr) and support the hypothesis that stellar activity may be responsible of the measured deviations of the transit times.Comment: 7 pages, 4 figures, 3 tables, accepted to Astronomische Nachrichte

stoRNA: Stateless Transparent Proofs of Storage-time

Proof of Storage-time (PoSt) is a cryptographic primitive that enables a server to demonstrate non-interactive continuous availability of outsourced data in a publicly verifiable way. This notion was first introduced by Filecoin to secure their Blockchain-based decentralized storage marketplace, using expensive SNARKs to compact proofs. Recent work employs the notion of trapdoor delay function to address the problem of compact PoSt without SNARKs. This approach however entails statefulness and non-transparency, while it requires an expensive pre-processing phase by the client. All of the above renders their solution impractical for decentralized storage marketplaces, leaving the stateless trapdoor-free PoSt with reduced setup costs as an open problem. In this work, we present stateless and transparent PoSt constructions using probabilistic sampling and a new Merkle variant commitment. In the process of enabling adjustable prover difficulty, we then propose a multi-prover construction to diminish the CPU work each prover is required to do. Both schemes feature a fast setup phase and logarithmic verification time and bandwidth with the end-to-end setup, prove, and verification costs lower than the existing solutions

Relationship between body mass index and physical fitness in Italian prepubertal schoolchildren

The objective of this study was to investigate the association between physical fitness and body mass index categories (obesity, OB; overweight, OW; normal-weight, NW; and underweight, UW) in prepubertal children. Anthropometric and physical fitness characteristics were collected from a convenience sample of 30472 Italian schoolchildren (6\u201311 years old). Six field-based tests were used: L\ue9ger, agility shuttle, long jump, frontal throw of the basketball, Sit & Reach and standing balance. Significant differences were found in the anthropometric characteristics, physical fitness and weight status prevalence between girls and boys (p<0.05) and, except for flexibility, by age class (p<0.05). Obese children performed worse than their NW counterparts in aerobic capacity (p<0.001), agility (p<0.001), muscular power of the lower limb (p<0.001) and balance (p<0.001). Conversely, children with obesity showed greater upper limb power than NW children (p<0.001). The discrepancy in physical fitness between OB and NW children increased in older girls (flexibility, p = 0.002; muscular power of the lower and upper limb, p = 0.002 and p = 0.005) and boys (aerobic capacity, p = 0.009; agility, p = 0.006; standing balance, p = 0.019; muscular power of the lower and upper limb, p<0.001 and p = 0.011) compared to their younger counterparts. On the other hand, UW children performed worse than NW children mainly in terms of muscular power of the arms (p<0.001). Additionally, there was an increasing disparity in the frontal throw test scores of UW and NW girls (p = 0.003) and boys (p = 0.011) in older children compared to younger children. In conclusion, the effect of body mass index on children\u2019s physical fitness intensifies with age. OB and OW negatively affect aerobic capacity, agility, lower limb power and balance but positively affect upper limb power. UW negatively affects upper limb power. This study underscores the importance of preventing childhood OW, OB, and UW in early life to promote children\u2019s health and proper fitness development

Influência do magnésio, boro e manganês na absorção de zinco por raízes destacadas de duas cultivares de arroz.

Os efeitos do magnésio, boro e manganês na absorção de zinco foram estudados usando-se o método de cinética de absorção com Zn65 por raízes destacadas das cultivares de arroz IAC 165 e IAC 201

Efeitos do alumínio em pimenteiras do reino (piper nigrum, L.) cultivadas em solução nutritiva.

A pimenteira do reino (Piper nigrum, L.) vem sendo cultivada, em sua maior parte, em áreas com solos de baixa fertilidade natural, caracterizadas por baixa saturação por bases, alta saturação de alumínio e acidez elevada. Visando estudar os efeitos do alumínio sobre a cultura foi conduzido um experimento com a cultivar Guajarina em solução nutritiva. As doses de alumínio estudadas foram: 0; 5; 10; 15; 20 e 40mg/L. O sintoma inicial de toxidez de alumínio foi caracterizado por um retardamento no crescimento radicular, com aumento no diâmetro das raízes. Observou-se efeito positivo do alumínio na produção de matéria seca com adição de até 15mg/L na solução, o que correspondeu a maior absorção de P, K, Ca, Mg, Mn, Fe e AL Conclui-se que a pimenteira é tolerante à presença de concentrações de Al inferiores a 20mg/L no substrato. Doses superiores provocam distúrbios nutricionais com redução no crescimento da plant

Influência do manganês sobre a nutrição mineral e crescimento da pimenteira do reino (Piper nigrum, L.).

A pimenteira do reino (Piper nigrum, L.) vem sendo cultivada em sua maior parte em solos com acidez elevada e balia saturação por bases. O manganês em condições de alta acidez pode provocar toxidez às plantas. Visando estudar os efeitos do manganês nessa cultura foi conduzido um experimento com a cultivar Guajarina em solução nutritiva, O manganês foi fornecido nas concentrações de 0; 10; 20; 30; 40 e 50 mg/L. Na ausência do elemento foram observados sintomas de deficiência e redução no crescimento. O excesso de manganês (30 mg/L) na solução nutritiva reduziu o desenvolvimento das plantas e a absorção de P, K, Ca, Mg, Cu, Fe e ZN. Observaram-se sintomas de toxidez de manganês a partir da concentração de 20 mg/L, caracterizados por cloróse e pontos necróticos nas folhas

Renal Stone Formation in Patients with Inflammatory Bowel Disease

Kidney stones are more common in patients with inflammatory bowel disease (IBD) than in the general population. The main lithogenetic risk factors were evaluated in patients affected by Crohn\u27s disease and ulcerative colitis. Our results show the presence of several factors, besides hyperoxaluria, in patients with IBD although their behaviour appears different in Crohn\u27s disease and ulcerative colitis at pre- and post-operative stages. Before surgery in patients with Crohn\u27s disease we found a decreased citrate (p \u3c 0.001) and magnesium (p \u3c 0.005) excretion together with a low urinary volume (p \u3c 0.001) and pH (p \u3c 0.005). After surgery patients with Crohn\u27s disease showed a further reduction of magnesium and citrate. Patients with ulcerative colitis before surgery showed a reduced citrate excretion (p \u3c 0.05) and a more acidic pH (p \u3c 0.05) than healthy subjects. Surgical treatment of proctocolectomy with ileal pouch-anal anastomosis seems to increase the risk of stone formation; in fact, after surgery we observed a relevant decrease of urinary volume (p \u3c 0.001), pH (p \u3c 0.0001) and urinary excretion of citrate (p \u3c0.0001) as well as magnesium (p \u3c 0.005). Patients with IBD seem to be at greater risk of stone formation than patients with idiopathic calcium lithiasis; in fact, they show a lower excretion of citrate (p \u3c 0.001) and magnesium (p \u3c 0.001) together with a low urinary pH (p \u3c 0.001) and volume (p \u3c 0.001). Urinary volume reduction is probably one of the major risk factors together with the decrease of small molecular weight inhibitors that is a constant finding in all patients with IBD

TASTE. III. A homogeneous study of transit time variations in WASP-3b

The TASTE project is searching for low-mass planets with the Transit Timing Variation (TTV) technique, by gathering high-precision, short-cadence light curves for a selected sample of transiting exoplanets. It has been claimed that the "hot Jupiter" WASP-3b could be perturbed by a second planet. Presenting eleven new light curves (secured at the IAC80 and UDEM telescopes) and re-analyzing thirty-eight archival light curves in a homogeneous way, we show that new data do not confirm the previously claimed TTV signal. However, we bring evidence that measurements are not consistent with a constant orbital period, though no significant periodicity can be detected. Additional dynamical modeling and follow-up observations are planned to constrain the properties of the perturber or to put upper limits to it. We provide a refined ephemeris for WASP-3b and improved orbital/physical parameters. A contact eclipsing binary, serendipitously discovered among field stars, is reported here for the first time.Comment: 10 pages, 6 figures, 4 tables; accepted for publication in A&

Studies on the zinc phosphate relationships in plant nutrition

This paper deals with the results of experiments designed to study the nature of the effect of phosphate (P) ion on the absorption of zinc (Zn) by plants. Due to the conflicting results found in the literature the following working hypothesis were raised and checked: a. R decreases Zn levels in the top by interfering with its uptake at the root level; b. decreases Zn uptake by roots due to preciptation at their surface; c. R decreases Zn content in the top by a negative effect on the upward movement of the absorbed element; d. R decreases Zn uptake in soil conditions by rendering it unavailable. Experiments with excised roots and whole plants were conducted using barley as an indicator. Experiments with excised roots and whole plants were carried out at there Zn concentraions (5 x 10-6M, 5 x 10-5M, and 5 x 10-4M) a pH 5.0 6.0 and 7.0. In the farmer trials 0,5 g of roots excised from 7 day old seedlings were used during an uptake period of 30 minutes; phosphates of Na, K, NH4, Ca and Mg were used at the concentrations of 10-5M, 10-4M and 5 x 10-3M. In order to better define a possible role of the accompanying cation same experiments were repeated replacing the phosphate by the chloride ion. The effect of the internal R status of the plant both of he upake and translocation was studied using respectively roots excised from plants previously grown in phosphate solutions (10-4M, 10-3M, and 5 x 10-3M) and whole plants (0, 10-4M, 10-3M and 10-2M). The influence of phosphatic fertilization was assessed by supplying varying rates of R (0, 200 and 400 ppm) plus other macro and micronutrients in standard amounts to three soil types (Regosol, Reed yellow Latosol sand phase and Reed Latosol) in the presence and in the abscence of lime. In all experiments 65Zn was used as tracer. The main conclusions were the following: a. all salts used in soilless experiments reduced Zn uptake by non competitive inhibition; b. the size of the effect is pH dependent; c. inhibition is greater when either R or Cl are accompanied divalent cation; d. effect is higher than Cl's; e. Precipitation of Zn by R in soilltss mtdium may take place depending upon concentration and pH, the phenomenon occurring either in them edium it self or at the surface; f. previous phosphatic nutrition did not decrease Zn uptake having however, slight, negative effect on translocation when high levels of the anion were used in the pretreament combined with low concentrations of the micronutrient during the experimental period; g. phosphatic fertilization and liming decreased Zn concentration in the olant having no lowering effect on its availability in the soil as revealed by a chemical method, the first variable actually increasing absorptionas determined by the "L" values thereof.Uma série de experimentos com raízes destacadas e plantas inteiras de cevada (em solução nutritiva ou solo) deu apoio à conclusão de que a deficiência de zinco induzida pelo fosfato pode ser explicada pela operação de vários processos: inibição não competitiva de absorção do zinco; precipitação de fosfato de zinco na superfície das raízes; redução na translocação para a parte aérea; efeito de diluição resultante de alta velocidade de crescimento causada pelo fósforo no meio