Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor

We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A = -4.92±0.61±0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections

Measurement of the vector analyzing power in elastic electron-proton scattering as a probe of double photon exchange amplitudes

We report the first measurement of the vector analyzing power in inclusive transversely polarized elastic electron-proton scattering at Q^2 = 0.1 (GeV/c)^2 and large scattering angles. This quantity should vanish in the single virtual photon exchange, plane wave impulse approximation for this reaction, and can therefore provide information on double photon exchange amplitudes for electromagnetic interactions with hadronic systems. We find a non-zero value of A=-15.4+/-5.4 ppm. No calculations of this observable for nuclei other than spin 0 have been carried out in these kinematics, and the calculation using the spin orbit interaction from a charged point nucleus of spin 0 cannot describe these data.Comment: 4 pages, 2 figures, submitted to Phys. Rev. Let

Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor

We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A=-4.92 +- 0.61 +- 0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections.Comment: 4 pages, 3 figures, submitted to Physical Review Letters, Sept 199

The social cost of chronic kidney disease in Italy

This study aims to estimate the mean annual social cost per patient with chronic kidney disease (CKD) by stages 4 and 5 pre-dialyses and cost components in Italy. The multicenter cross-sectional study included all adult outpatients in charge of the 14 main Nephrology Centers of Tuscany Region during 7 weeks from 2012 to 2013. Direct medical costs have been estimated using tariffs for laboratory tests, diagnostic exams, visits, hospitalization and prices for drugs. Non-medical costs included expenses of low-protein special foods, travel, and formal and informal care. Patients' and caregivers' losses of productivity have been estimated as indirect costs using the human capital approach. Costs have been expressed in Euros (2016). Totals of 279 patients in stage 4 and 205 patients in stage 5 have been enrolled. The estimated mean annual social cost of a patient with CKD were a,notsign7422 (+/- a,notsign6255) for stage 4 and a,notsign8971 (+/- a,notsign6503) for stage 5 (p < 0.05). Direct medical costs were higher in stage 5 as compared to stage 4; direct non-medical costs and indirect costs accounted, respectively, for 41 and 5 % of the total social cost of CKD stage 4 and for 33 and 9 % of CKD stage 5. In Italy, the overall annual social cost of CKD was a,notsign1,809,552,398 representing 0.11 % of the Gross Domestic Product. Direct non-medical costs and indirect costs were weighted on the social cost of CKD almost as much as the direct medical cost. Patients, their families and the productivity system sustain the burden of the disease almost as much as the healthcare system. © 2016, The Author(s)

Measurement of the vector analyzing power in elastic electron-proton scattering as a probe of double photon exchange amplitudes

We report the first measurement of the vector analyzing power in inclusive transversely polarized elastic electron-proton scattering at Q2 = 0.1 (GeV/c)2 and large scattering angles. This quantity should vanish in the single virtual photon exchange, plane wave impulse approximation for this reaction, and can therefore provide information on double photon exchange amplitudes for electro- magnetic interactions with hadronic systems. We find a non-zero value of A=-15.4±5.4 ppm. No calculations of this observable for nuclei other than spin 0 have been carried out in these kinematics, and the calculation using the spin orbit interaction from a charged point nucleus of spin 0 cannot describe these data

Effects of atrazine on neotropical fish kidney, Piaractus mesopotamicus: a subchronical exposition and recovery assays.

Environmental and human health risks that atrazine may cause justified its prohibition in European Union countries since 2005, but it is widely used in Brazil and often found above permitted levels (2.0 ?g/l-1) in river basins. The aim of this study was to evaluate the effects of atrazine by toxicity and recovery assays on trunk kidney, the main target organ of this herbicide, on Piaractus mesopotamicus (pacu) to sublethal concentration (3.57 mg / l-1) and non-lethal realistic concentration (3.0 ?g/l-1). For the exposure assay 12 pacu fingerlings were kept for 30 days in glass tanks with test concentrations presented above, including the control group (0.0 ?g/l-1). The partial replacement of atrazine occurred every 72 hours with the renovation of 1/3 of the water volume. For the recovery assay, other tanks with 12 samples by group were maintained similarly, after 30 days gradually the contaminated water was substituted by clean water and the fingerlings were maintained for another 14 days under these conditions. At the end of each assay, kidney samples were obtained and processed to histopathological and ultrastructural analysis. The kidney samples from all treatments showed Myxobolus sp. infection, which is common in Brazilian teleosts from natural environment or from fish farm, inducing degeneration of collecting tubule with massive reaction of melanomacrophages. Granulomas were also seen. The kidneys from sublethal exposition group showed also degenerative changes in proximal tubules, where no parasites or melanomacrophage reaction were identified. In nonlethal exposition group just few samples presented degenerative changes in proximal tubule cells. The recovery assay of sublethal group indicated that the degenerative alterations in proximal tubule were maintained. The recovery of nonlethal group showed no changes in proximal tubules. All groups from exposition and recovery assay presented renal tubular hyperplasia. These results indicated that the sublethal concentration of atrazine tested can induce serious damage to tubular renal function and those damages were not recovered when the fish were kept for 14 days in cleaner water and that the realistic non lethal concentration tested (found in Brazilian river basins) seems did not affect at all the function of the nephron

Acute toxicity of commercial atrazine in Piaractus mesopotamicus: histopathological, ultrastructural, molecular, and genotoxic evaluation.

The aim of this work was to evaluate the sensitivity of Pacu fingerlings (Piaractus mesopotamicus) by measuring the effects of median lethal concentration (LC50) of atrazine (ATZ - 28.58 mg/L) after acute exposure (up to 96 h). The fish were exposed to the LC50 of ATZ for 96 h (28.58 mg/L) in a static system. During the experiment, the fingerlings were randomly distributed in four glass tanks (50 L) containing dechlorinated water. Four glass tanks were for the control group, and four were for the ATZ-exposed group (n=4 per glass tank), given a total number of 16 animals tested per group. The genotoxicity was evaluated by micronucleus (MN) test in erythrocytes from peripheral blood. Qualitative and semi-quantitative histopathological analyses, and also ultrastructural study, were applied in liver and kidney samples. Finally, the content of heat shock protein (Hsp70) in the liver was evaluated by the western blotting method. The morphological alterations in the liver, which was associated with increased expression of Hsp70, included nuclear and cytoplasmic vacuolization, cytoplasmic hyaline inclusions, and necrosis. The kidney presented edema and tubular cell degeneration with cytoplasmic hyaline inclusion. The semi-quantitative histopathological analyses indicated that the liver was more sensitive than kidney to ATZ-induced damage. Ultrastructural analysis showed that ATZ caused membrane alterations in several organelles and increased the number of lysosomes in hepatocytes and kidney proximal tubular cells. Nevertheless, no significant difference was observed in MN frequency in erythrocytes comparing treated and control groups. These results indicated that ATZ-induced damage to the kidney and liver function, ATZ at the concentration tested did not induce a significant difference in MN frequency in Pacu erythrocytes comparing treated and control groups, and also that Pacu fingerlings may be a good bioindicator for testing freshwater contamination.Made available in DSpace on 2017-11-23T23:19:07Z (GMT). No. of bitstreams: 1 2017AP19.pdf: 3572426 bytes, checksum: bb7a8accef499f70af6a60fa1788cb10 (MD5) Previous issue date: 2017-11-23bitstream/item/167350/1/2017AP19.pd

Effects of sublethal and realistic concentrations of the commercial herbicide atrazine in Pacu (Piaractus mesopotamicus): long-term exposure and recovery assays.

Abstract: Background and Aim: The commercial formulations of the herbicide atrazine (cATZ) are widely employed in Brazilian agriculture, and, as a consequence, ATZ has been found at levels above that established by law in the river basins in Brazil. Although the toxicity of ATZ in fish is well documented, there are few studies on the recovery capacity after cATZ exposure. This work aimed to evaluate, using several biomarkers, the toxic effects of long-term exposure to the sublethal (3.57 mg/L) and nonlethal realistic (3.00 ?g/L) cATZ concentrations followed by a recovery assay, in fingerlings of a Brazilian teleost, the Piaractus mesopotamicus (pacu). Materials and Methods: Pacu fingerlings were housed in glass tanks and divided into the following experimental groups (two tanks/group): Exposure control = EC, recovery control = RC, the sublethal groups exposed to 3.57 mg/L of cATZ, (sublethal exposure group = SLE and sublethal recovery group = SLR) and the nonlethal groups treated with 3.00 μg/L of cATZ (nonlethal exposure group = NLE and nonlethal recovery group = NLR). The exposure assay was semi-static with a duration of 30 days and the recovery assay (after cATZ withdrawal) lasted 14 days. Several biomarkers were evaluated in fingerlings from all groups: The swimming behavior, the body weight gain, the micronucleus formation and nuclear alterations in erythrocytes, and the hepatic and renal histopathology analyzed by qualitative and semi-quantitative morphological methods (using light and electron microscopy). Results: No significant difference in weight gain was observed among the groups after the exposure and recovery assays. The sublethal exposure induced impaired swimming movements, significant histopathological alterations, including necrosis in the liver and kidney, and a significant increase in the frequency of micronuclei in erythrocytes. The nonlethal exposure induced only subtle histopathological changes in the liver and kidney. After recovery assay, no genotoxic alteration was noted in pacu exposed to sublethal concentration, while the cATZ-induced kidney damage was partially reversed but not the hepatic injury. Conclusion: cATZ exhibits long-term toxic effects on pacu, even at relatively low concentrations, affecting mainly the liver and the kidney, and the effects of sublethal concentration are only partially reversed after cATZ withdrawal