ABSTRACT
The nomadic behavior of Roma people has allowed their cultural interaction with people from different continents. Brazil has received Roma immigrants since its colonization, and there are currently more than 800,000 Roma people among the Brazilian population. This article describes the ethnobotanical knowledge of two Calon families (Alves a nd Dantas) esta blished in hinterland cities of Pernambuco, northeastern Brazil. The survey was conducted with 23 informants (≥ 40 years old, 85% of the target audience) selected through the snowball technique and using semi - structured interviews. The plants mentioned wer e collected, identified and deposited in the IPA and UFP herbaria. The 157 species (85 native) are used for food, condiment, cosmetic, medicinal, ritualistic, technological, veterinary, and other purposes. The useful flora and forms of use are similar to t hose reported by non - Roma communities living in the same region, showing a kind of mimicry adopted by the Roma people, yet maintaining their cultural identity.
El comportamiento nómada de los gitanos ha permitido su interacción cultural con personas de diferentes continentes. Brasil ha recibido inmigrantes romaníes desde su colonización y actualmente hay más de 800.000 romaníes entre la población brasileñ a. Este artículo describe el conocimiento etnobotá nico de dos familias Calon (Alves y Dantas) establecidas en ciudades del interior de Pernambuco, noreste de Brasil. La encuesta se realizó con 23 informantes (≥ 40 años, 85% del público objetivo) seleccionados mediante la técnica de bola de nieve y mediant e entrevistas semiestructuradas. Las plantas mencionadas fueron recolectadas, identificadas y depositadas en los herbarios IPA y UFP. Las 157 especies (85 nativas) se utilizan para alimentos, condimentos, cosméticos, medicinales, ritualistas, tecnológicos, veterinarios y otros fines. La flora útil y las formas de uso son similares a las reportadas por las comunidades no gitanas que viven en la misma región, mostrando una especie de mimetismo adoptado por el pueblo gitano, pero manteniendo su identidad cultu ral.
Subject(s)
Humans , Plants, Medicinal , Rome , Ethnobotany , Brazil , Surveys and QuestionnairesABSTRACT
The chemical bond is one of the most powerful, yet much debated concepts in chemistry, explaining property trends in solids. Recently, a novel type of chemical bonding was identified in several higher chalcogenides, characterized by a unique property portfolio, unconventional bond breaking, and sharing of about one electron between adjacent atoms. This metavalent bond is a fundamental type of bonding in solids, besides covalent, ionic, and metallic bonding, raising the pertinent question as to whether there is a well-defined transition between metavalent and covalent bonds. Here, three different pseudo-binary lines, namely, GeTe1- x Sex , Sb2 Te3(1- x ) Se3 x , and Bi2-2 x Sb2 x Se3 , are studied, and a sudden change in several properties, including optical absorption ε2 (ω), optical dielectric constant ε∞ , Born effective charge Z*, electrical conductivity, as well as bond breaking behavior for a critical Se or Sb concentration, is evidenced. These findings provide a blueprint to experimentally explore the influence of metavalent bonding on attractive properties of phase-change materials and thermoelectrics. Particularly important is its impact on optical properties, which can be tailored by the amount of electrons shared between adjacent atoms. This correlation can be used to design optoelectronic materials and to explore systematic changes in chemical bonding with stoichiometry and atomic arrangement.
ABSTRACT
Gypsies have been in Brazil since the 16th century and today they are more than 800,000 in the country. This article describes the veterinary use of plants by Calon gypsies living in Pernambuco, Northeastern Brazil. The research was carried out with 23 people (> 40 years old), using semi-structured forms and the snowball technique. The cited species were collected during guided tours, identified and deposited at the IPA and UFP herbaria. Ten plants were indicated for veterinary use: Agave sisalana (Asparagaceae), Aspidosperma pyrifolium (Apocynaceae), Apodanthera congestiflora (Cucurbitaceae), Heliotropium indicum (Boraginaceae), Lippia alba (Verbenaceae), Momordica charantia (Cucurbitaceae), Nicotiana tabacum (Solanaceae), Passiflora cincinnata (Passifloraceae), Phaseolus lunatus (Fabaceae), and Solanum paniculatum (Solanaceae). The participants cited various methods of preparation and therapeutic indications for ectoparasitic infections, digestive disorders, and eye and respiratory infections in farm animals. Apodanthera congestiflora and H. indicum stood out for prophylaxis and treatment of Newcastle disease in fowl.
Los gitanos están en Brasil desde el siglo XVI y hoy, son más de 800.000 en el país. Este artículo describe el uso veterinario de plantas por gitanos Calon que viven en Pernambuco, Noreste de Brasil. La encuesta fue realizada con 23 personas (> 40 años), utilizando formularios semi-estructurados y la técnica bola de nieve. Las especies citadas fueron recolectadas en giras guiadas, identificadas y depositadas en los herbarios IPA y UFP. Diez plantas fueron citadas para uso veterinario: Agave sisalana (Asparagaceae), Aspidosperma pyrifolium (Apocynaceae), Apodanthera congestiflora (Cucurbitaceae), Heliotropium indicum (Boraginaceae), Lippia alba (Verbenaceae), Momordica charantia (Cucurbitaceae), Nicotiana tabacum (Solanaceae), Passiflora cincinnata (Passifloraceae), Phaseolus lunatus (Fabaceae) y Solanum paniculatum (Solanaceae). Los participantes citaron varios modos de preparación e indicaciones terapéuticas para infecciones ectoparasitarias, disturbios digestivos, infecciones oculares y respiratorias en animales domésticos. Apodanthera congestiflora y H. indicum se destacaron en la profilaxis y tratamiento de la enfermedad de Newcastle en aves.
Subject(s)
Humans , Plants, Medicinal/chemistry , Veterinary Medicine , Rome , Medicine, Traditional , Brazil , EthnopharmacologyABSTRACT
Glutamate amidation, a secondary modification of the peptidoglycan, was first identified in Staphylococcus aureus It is catalyzed by the protein products of the murT and gatD genes, which are conserved and colocalized in the genomes of most sequenced Gram-positive bacterial species. The MurT-GatD complex is required for cell viability, full resistance to ß-lactam antibiotics, and resistance to human lysozyme and is recognized as an attractive target for new antimicrobials. Great effort has been invested in the study of this step, culminating recently in three independent reports addressing the structural elucidation of the MurT-GatD complex. In this work, we demonstrate through the use of nonstructural approaches the critical and multiple roles of the C-terminal domain of MurT, annotated as DUF1727, in the MurT-GatD enzymatic complex. This domain provides the physical link between the two enzymatic activities and is essential for the amidation reaction. Copurification of recombinant MurT and GatD proteins and bacterial two-hybrid assays support the observation that the MurT-GatD interaction occurs through this domain. Most importantly, we provide in vivo evidence of the effect of substitutions at specific residues in DUF1727 on cell wall peptidoglycan amidation and on the phenotypes of oxacillin resistance and bacterial growth.
Subject(s)
Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor/chemistry , Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor/metabolism , Protein Domains/physiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor/genetics , Chromatography, High Pressure Liquid , Mutagenesis, Site-Directed , Peptidoglycan/metabolism , Protein Domains/genetics , Protein Stability , Staphylococcus aureus/geneticsABSTRACT
Optimal processing conditions for fabrication of dense single-phase 6L-Ba2CoTeO6 ceramics via the solid-state reaction method were determined. These ceramics possess a room-temperature crystal structure described by the centrosymmetric P3[combining macron]m1 space group. Polarized Raman spectroscopy enabled the observation of all the 25 predicted Raman modes and assignment of their symmetries. On cooling, BCTO ceramics exhibit two antiferromagnetic transitions at 3 K and 12.5 K, in broad agreement with a recent single-crystal study [P. Chanlert, N. Kurita, H. Tanaka, D. Goto, A. Matsuo and K. Kindo, Phys. Rev. B: Condens. Matter Mater. Phys., 2016, 93, 094420]. Low temperature Fourier-transform infrared reflectivity analyses suggest the antiferromagnetic phase transitions to be driven by small distortions of the CoO6 octahedra, lowering locally their C3v symmetry. This causes splitting of the associated vibrational modes, but without a long-range structural change. AC impedance spectroscopy revealed BCTO ceramics to be leaky insulators with an activation energy for conduction of â¼0.15-0.25 eV, which suggests electron hopping between mixed oxidation states of Co.
ABSTRACT
We report the synthesis of nanocrystals with an optical feature in the THz range. To do so, we develop a new synthetic procedure for the growth of HgTe, HgSe, and HgS nanocrystals, with strong size tunability from 5 to 200 nm. This is used to tune the absorption of the nanocrystals all over the infrared range up to terahertz (from 2 to 65 µm for absorption peak and even 200 µm for cutoff wavelength). The interest for this procedure is not limited to large sizes since for small objects we demonstrate low aggregation and good shape control (i.e., spherical object) while using nonexpansive and simple mercury halogenide precursors. By integrating these nanocrystals into an electrolyte-gated transistor, we evidence a change of carrier density from p-doped to n-doped as the confinement is vanishing.
ABSTRACT
A comprehensive set of optical vibrational modes of monoclinic taurine crystals was determined by Raman scattering, and infrared reflectivity and transmission spectroscopies. By using appropriate scattering/reflection geometries, the vibrational modes were resolved by polarization and the most relevant modes of the crystal could be assigned. In particular, we were able to review the symmetry of the gerade modes and to resolve ambiguities in the literature. Owing to the non-orthogonal character of Bu modes in monoclinic crystals (lying on the optic axial plane), we carried out a generalized Lorentz dispersion analysis consisting of simultaneous adjust of infrared-reflectivity spectra at various light polarization angles. The Au modes (parallel to the C2-axis) were treated within the classical Lorentz model. The behavior of off-diagonal and diagonal terms of the complex dielectric tensors and the presence of anomalous dispersion were discussed as consequences of the low symmetry of the crystal.
Subject(s)
Infrared Rays , Spectrum Analysis, Raman , Taurine/chemistry , Crystallization , ElectricityABSTRACT
Self-doped colloidal quantum dots (CQDs) attract a strong interest for the design of a new generation of low-cost infrared (IR) optoelectronic devices because of their tunable intraband absorption feature in the mid-IR region. However, very little remains known about their electronic structure which combines confinement and an inverted band structure, complicating the design of optimized devices. We use a combination of IR spectroscopy and photoemission to determine the absolute energy levels of HgSe CQDs with various sizes and surface chemistries. We demonstrate that the filling of the CQD states ranges from 2 electrons per CQD at small sizes (<5 nm) to more than 18 electrons per CQD at large sizes (≈20 nm). HgSe CQDs are also an interesting platform to observe vanishing confinement in colloidal nanoparticles. We present lines of evidence for a semiconductor-to-metal transition at the CQD level, through temperature-dependent absorption and transport measurements. In contrast with bulk systems, the transition is the result of the vanishing confinement rather than the increase of the doping level.
ABSTRACT
Fermi showed that, as a result of their quantum nature, electrons form a gas of particles whose temperature and density follow the so-called Fermi distribution. As shown by Landau, in a metal the electrons continue to act like free quantum mechanical particles with enhanced masses, despite their strong Coulomb interaction with each other and the positive background ions. This state of matter, the Landau-Fermi liquid, is recognized experimentally by an electrical resistivity that is proportional to the square of the absolute temperature plus a term proportional to the square of the frequency of the applied field. Calculations show that, if electron-electron scattering dominates the resistivity in a Landau-Fermi liquid, the ratio of the two terms, b, has the universal value of b = 4. We find that in the normal state of the heavy Fermion metal URu(2)Si(2), instead of the Fermi liquid value of 4, the coefficient b = 1 ± 0.1. This unexpected result implies that the electrons in this material are experiencing a unique scattering process. This scattering is intrinsic and we suggest that the uranium f electrons do not hybridize to form a coherent Fermi liquid but instead act like a dense array of elastic impurities, interacting incoherently with the charge carriers. This behavior is not restricted to URu(2)Si(2). Fermi liquid-like states with b ≠ 4 have been observed in a number of disparate systems, but the significance of this result has not been recognized.
Subject(s)
Optical Phenomena , Ruthenium/chemistry , Silicon Compounds/chemistry , Uranium/chemistry , Electric Conductivity , Spectrum Analysis , TemperatureABSTRACT
Describes the case of a 6-year-old girl who was stung by a Centruroides testaceus, a scorpion native to the Lesser Antilles, in the Guarulhos International Airport, São Paulo, Brazil, as she disembarked from a flight coming from the Caribbean. The patient presented only local symptoms (a small area of erythema and pain at the sting site), which were resolved after a few hours with analgesics, without the need for antivenom. Physicians who treat patients stung by scorpions should be alert to the possibility of such accidents being caused by non native species, especially those cases that occur near airports or ports.
Descreve-se um caso de menina de 6 anos de idade picada por um Centruroides testaceus, escorpião nativo das Antilhas, no interior do Aeroporto Internacional de Guarulhos, São Paulo, Brasil, após ter desembarcado de um vôo vindo do Caribe. A paciente apresentou apenas sintomas locais (pequena área de eritema e dor no local da picada), resolvidos em algumas horas com uso de analgésicos, não necessitando receber soro antiveneno. Os médicos que tratam pacientes picados por escorpiões devem estar precavidos quanto à possibilidade dos acidentes serem causados por espécies não-nativas, especialmente nos que ocorrem próximos a aeroportos ou portos.
Subject(s)
Animals , Child , Female , Humans , Spider Bites/diagnosis , Scorpions/classification , Spider Bites/etiology , TravelABSTRACT
Describes the case of a 6-year-old girl who was stung by a Centruroides testaceus, a scorpion native to the Lesser Antilles, in the Guarulhos International Airport, São Paulo, Brazil, as she disembarked from a flight coming from the Caribbean. The patient presented only local symptoms (a small area of erythema and pain at the sting site), which were resolved after a few hours with analgesics, without the need for antivenom. Physicians who treat patients stung by scorpions should be alert to the possibility of such accidents being caused by non native species, especially those cases that occur near airports or ports.
Subject(s)
Scorpion Stings/diagnosis , Scorpions/classification , Animals , Child , Female , Humans , Scorpion Stings/etiology , TravelABSTRACT
Silicon beam splitters several millimeters thick offer numerous advantages over thin freestanding dielectric beam splitters. For routine spectroscopy for which resolutions of better than 1 cm(-1) are not required, a silicon beam splitter can replace several Mylar beam splitters to span the entire far-infrared region. In addition to superior long-wavelength performance that extends well into the terahertz region, the silicon beam splitter has the additional advantage that its efficiency displays little polarization dependence.
ABSTRACT
A series of low-melting, thermally stable cadmium metal-organic chemical vapor deposition (MOCVD) precursors have been synthesized, structurally and spectroscopically characterized, and implemented in growth of highly conductive and transparent CdO thin films. One member of the series, bis(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato)(N,N-diethyl-N',N'-dimethyl-ethylenediamine)cadmium(II), Cd(hfa)(2)()(N,N-DE-N',N'-DMEDA), represents a particularly significant improvement over previously available Cd precursors, owing to the low melting point and robust thermal stability. High-quality CdO films were grown by MOCVD on glass and single-crystal MgO(100) between 300 and 412 degrees C. Film growth parameters and substrate surface have large effects on microstructure and electron carrier transport properties. Enhanced mobilities observed for highly biaxially textured films grown on MgO(100) vs glass are attributed, on the basis of DC charge transport and microstructure analysis, to a reduction in neutral impurity scattering and/or to a more densely packed grain microstructure. Although single-grained films grown on MgO(100) exhibit greater mobilities than analogues with discrete approximately 100 nm grains and similar texture, this effect is attributed, on the basis of charge transport and Hall effect measurements as well as optical reflectivity analysis, to differences in carrier concentration rather than to reduced grain boundary scattering. Unprecedented conductivities and mobilities as high as 11,000 S/cm and 307 cm(2)/V.s, respectively, are obtained for epitaxial single-grained films (X-ray diffraction parameters: fwhm(omega) = 0.30 degrees, fwhm(phi) = 0.27 degrees ) grown in situ on MgO(100) at a relatively low temperature (400 degrees C).
ABSTRACT
La infección por virus de papiloma humano es un importante factor de riesgo para cáncer cérvico-uterino y sus precursores. Se realizó un estudio prospectivo para analizar las características epidemiológicas y cofactores de VPH, en 690 pacientes entre 15 y 50 años, que acudieron al servicio de ginecología durante agosto de 2000 y agosto de 2001, practicándoseles interrogatorio dirigido, citología y colposcopia. La frecuencia de infección por VPH fue de 6,23 por ciento. La edad promedio fue de 30,55 años. La sexarquia promedio fue 18,11 años. El número de parejas promedio fue de 2,12 y el 30,23 por ciento tenían hábitos tabáquicos. Doce casos (27,9 por ciento) con VPH presentaron asociación con lesión intraepitelial cervical
