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ABSTRACT Egg production is an important economic activity in Brazil, with about 697 million eggs produced annually. The conventional cage system is commonly used for egg production. However, there has been a growing concern for the welfare of laying hens around the world. In this context, many countries have issued laws, protocols, and other normative technical specifications to ensure the welfare of layers. This study aims at identifying similarities and differences between international standards and Brazilian protocols using the Comparative Law perspective. This article reports an analytical study of selected protocols, performing three analyses using the Comparative Law method. The research concludes that some items of the Brazilian protocols of good egg production practices, such as farm inspection, treatment of diseases, temperature, ventilation, beak trimming, feed and water supply, correspond to international specifications, whereas others, such as housing, freedom movement, use of equipment, and transport, are less strict.

OBJECTIVES. This study was undertaken to determine if Navy veterans who participated in an atmospheric nuclear test in 1958 were at increased risk of death from certain cancers. METHODS. Cancer mortality risk of 8554 Navy veterans who participated in an atmospheric nuclear test in the Pacific was compared with that of 14,625 Navy veterans who did not participate in any test. Radiation dosage information was obtained from film badges for 88% of the test participants. RESULTS. The median radiation dose for the test participants was 388 mrem (3.88 millisieverts [mSv]). Among participants who received the highest radiation dose (> 1000 mrem, or 10 mSv), an increased mortality risk for all causes (relative risk [RR] = 1.23; 95% confidence interval [CI] = 1.04, 1.45), all cancers (RR = 1.42; 95% CI = 1.03, 1.96), and liver cancer (RR = 6.42; 95% CI = 1.17, 35.3) was observed. The risk for cancer of the digestive organs was elevated among test participants (rate ratio = 1.47; 95% CI = 1.06, 2.04) but with no significant dose-response trend. Many of the cancers of a priori interest were not significantly elevated in the overall test participant group or in the group that received the highest radiation dose. CONCLUSIONS. Most of the cancers suspected of being radiogenic were not significantly elevated among the test participants. Nevertheless, increased risks for certain cancers cannot be ruled out at this time. Veterans who participated in the nuclear weapons tests should continue to be monitored.

The primary reason for concern about the adverse effects of exposure to Agent Orange is attributable to its toxic contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or dioxin. We studied adipose tissues from 36 Vietnam veterans, a similar group of 79 non-Vietnam veterans, and 80 civilians; the tissue specimens were selected from the 8,000 archived tissues collected from the non-institutionalized general population by the US Environmental Protection Agency. The geometric mean (+/- standard deviation) dioxin levels in adipose tissue for Vietnam veterans, non-Vietnam veterans, and civilian controls were 11.7 (+/- 1.7), 10.9 (+/- 1.7), and 12.4 (+/- 1.9) parts per trillion on a lipid weight basis, respectively. The mean levels for these groups were not significantly different from each other with or without adjustment for age of individuals, body mass index, and specimen collection year. In addition, none of the surrogate measures of Agent Orange exposure such as military branch, service within specific geographic region, military occupation, and troop location in relation to recorded Agent Orange spray was associated with the dioxin levels in adipose tissue of Vietnam veterans. Our results suggest that heavy exposure to Agent Orange or dioxin for most US troops was unlikely.

We perform systematic investigations of transport through graphene on hexagonal boron nitride (hBN) substrates, together with confocal Raman measurements and a targeted theoretical analysis, to identify the dominant source of disorder in this system. Low-temperature transport measurements on many devices reveal a clear correlation between the carrier mobility μ and the width n* of the resistance peak around charge neutrality, demonstrating that charge scattering and density inhomogeneities originate from the same microscopic mechanism. The study of weak localization unambiguously shows that this mechanism is associated with a long-ranged disorder potential and provides clear indications that random pseudomagnetic fields due to strain are the dominant scattering source. Spatially resolved Raman spectroscopy measurements confirm the role of local strain fluctuations, since the linewidth of the Raman 2D peak-containing information of local strain fluctuations present in graphene-correlates with the value of maximum observed mobility. The importance of strain is corroborated by a theoretical analysis of the relation between μ and n* that shows how local strain fluctuations reproduce the experimental data at a quantitative level, with n* being determined by the scalar deformation potential and μ by the random pseudomagnetic field (consistently with the conclusion drawn from the analysis of weak localization). Throughout our study, we compare the behavior of devices on hBN substrates to that of devices on SiO2 and SrTiO3, and find that all conclusions drawn for the case of hBN are compatible with the observations made on these other materials. These observations suggest that random strain fluctuations are the dominant source of disorder for high-quality graphene on many different substrates, and not only on hexagonal boron nitride. ; A. F. M. gratefully acknowledges support by the Swiss National Science Foundation (SNF) and by the National Center of Competence in Research on Quantum Science and Technology (NCCR QSIT). F. G. acknowledges support from the Spanish Ministry of Economy (MINECO) through Grant No. FIS2011-23713 and the European Research Council (ERC) Advanced Grant (Contract No. 290846). C. S. and S. E. acknowledge experimental help from F. Buckstegge, J. Dauber, B. Terrés, F. Volmer, and M. Drögeler and financial support from Deutsche Forschungsgemeinschaft (DFG) and European Research Council (ERC) (Contract No. 280140). A. F. M., F. G., and C. S. acknowledge funding from the European Union (EU) under the Graphene Flagship.

S.C. acknowledges a Marie Skłodowska-Curie Individual Fellowship under grant BioGraphING (ID: 798851) and P.G. acknowledges a Marie Skłodowska-Curie Individual Fellowship under grant TherSpinMol (ID: 748642) from the European Union's Horizon 2020 research and innovation programme. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan, and the CREST (JPMJCR15F3), JST. This work was supported by the Graphene Flagship (a European Union's Horizon 2020 research and innovation programme under grant agreement no. 649953), the Marie Curie ITN MOLESCO, an ERC advanced grant (Mols@Mols no. 240299), and a Spanish MCIU/AEI/FEDER project (PGC2018-094783).

Integrating and manipulating the nano-optoelectronic properties of Van der Waals heterostructures can enable unprecedented platforms for photodetection and sensing. The main challenge of infrared photodetectors is to funnel the light into a small nanoscale active area and efficiently convert it into an electrical signal. Here, we overcome all of those challenges in one device, by efficient coupling of a plasmonic antenna to hyperbolic phonon-polaritons in hexagonal-BN to highly concentrate mid-infrared light into a graphene pn-junction. We balance the interplay of the absorption, electrical and thermal conductivity of graphene via the device geometry. This approach yields remarkable device performance featuring room temperature high sensitivity (NEP of 82 pW= ffiffiffiffiffiffi Hz p ) and fast rise time of 17 nanoseconds (setup-limited), among others, hence achieving a combination currently not present in the state-of-the-art graphene and commercial mid-infrared detectors. We also develop a multiphysics model that shows very good quantitative agreement with our experimental results and reveals the different contributions to our photoresponse, thus paving the way for further improvement of these types of photodetectors even beyond mid-infrared range. ; F.H.L.K. acknowledges financial support from the Spanish Ministry of Economy and Competitiveness, through the "Severo Ochoa" Programme for Centres of Excellence in R& D (SEV-2015-0522), support by Fundacio Cellex Barcelona, Generalitat de Catalunya through the CERCA program, and the Agency for Management of University and Research Grants (AGAUR) 2017 SGR 1656. Furthermore, the research leading to these results has received funding from the European Union Seventh Framework Programme under grant agreement no. 785219 and no. 881603 Graphene Flagship for Core2 and Core3. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706). K.J.T. acknowledges funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 804349. R.H. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (national project RTI2018-094830-B-100 and the project MDM-2016-0618 of the Marie de Maeztu Units of Excellence Program) and the Basque Government (grant No. IT1164-19). S.C. acknowledges financial support from the Barcelona Institute of Science and Technology (BIST), the Secretaria d'Universitats i Recerca del Departament d'Empresa i Coneixement de la Generalitat de Catalunya and the European Social Fund (L'FSE inverteix en el teu futur)—FEDER. D.E. acknowledges partial support from the Army Research Office MURI "Ab-Initio Solid-State Quantum Materials" Grant No. W911NF18-1-0431. J.G. was supported by the ARL-MIT Institute for Soldier Nanotechnologies (ISN). T.S. and L.M.M. acknowledge support by Spain's MINECO under Grant No. MAT2017-88358-C3-1-R and the Aragon Government through project Q-MAD. ; Peer Reviewed ; Postprint (published version)