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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 534-551, jul. 2024. ilus, tab, graf
Artículo en Español | LILACS | ID: biblio-1538057

RESUMEN

The cultural significance of the flora used by the native Asheninka Sheremashe community in Ucayali, Peru was determined. To do this, a fieldwork of over 4 months was conducted, involving semi-structured interviews with 106 residents through non-probabilistic convenience sampling. The community utilizes 139 plant species in their daily lives, belonging to 120 genera and 52 families, with the most abundant being Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae, and Rutaceae. Furthermore, 25.9% of the species are of significant importance to theinhabitants according to the Cultural Index (CI), such as Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, among others. It can be concluded that the flora plays a prominent role in the life of the community, with the categories reporting the highest number of species being: food (29.35%), medicine (28.36%), culture (9.95%), construction (9.45%), lumber (6.97%), commerce (3.48%), craftsmanship (2.49%), toxic (2.49%), and other uses (7.46%)


Se determinó la importancia cultural de la flora empleada por la comunidad nativa Asheninka Sheremashe, en Ucayali, Perú. Para ello, se realizó un trabajo de campo de más de 4 meses, donde se aplicaron entrevistas semiestructuradas a 106 habitantes mediante un muestreo no probabilístico por conveniencia. La comunidad emplea 139 especies vegetales en su día a día, pertenecientes a 120 géneros y 52 familias; siendo las más abundantes las Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae y Rutaceae. Además, el 25.9% de las especies tiene gran importancia para los pobladores según el Índice Cultural (IC): Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, entre otras. Se concluye que la flora tiene un rol preponderante en la vida de la comunidad, siendo las categorías que presentaron mayor reporte de especies: alimentación (29.35%), medicina (28.36%), cultura (9.95%), construcción (9.45%), aserrío (6.97%), comercio (3.48%), artesanía (2.49%), tóxico (2.49%) y otros usos (7.46%)


Asunto(s)
Humanos , Flora , Etnobotánica , Medicina Tradicional , Perú , Encuestas y Cuestionarios
2.
Lupus ; 31(5): 637-645, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35382633

RESUMEN

OBJECTIVE: The objective is to describe the main characteristics of patients with systemic lupus erythematosus (SLE) in Argentina and to examine the influence of ethnicity on the expression of the disease. PATIENTS AND METHODS: RELESSAR is a multicentre register carried out by 106 researchers from 67 rheumatologic Argentine centres. It is a cross-sectional study of SLE (1982/1997 ACR) patients. RELESSAR electronic database includes demographic, cumulative SLE manifestations, SELENA-SLEDAI, SLICC-SDI, Katz's severity and Charlson's comorbidity indexes and treatment patterns. RESULTS: We included 1,610 patients, 91.7% were female with a median age at diagnosis of 28.1 ± 12.8; 96.2% met ≥4 ACR 1982/97 criteria. Frequent manifestations were arthritis (83.5%), malar rash (79.5%), photosensitivity (75.3%), haematological (63.8%) and renal disease (47.4%), antinuclear antibodies (96%), anti-dsDNA (66.5%) and anti-Smith antibodies (29%). The mean Selena-SLEDAI score at last visit was 3.18 (SD 4.3) and mean SDI was 1 (SD 1.3). The accumulated treatments most frequently used were antimalarials (90.4%), corticosteroids (90%), azathioprine (31.8%), intravenous cyclophosphamide (30.2%), mycophenolate mofetil or mycophenolic acid (24.5%), methotrexate (19.3%), belimumab 5.3% and rituximab 5.1%. Refractory lupus was diagnosed in 9.3% of the cases. The main causes of death were lupus activity (25.0%), activity and concomitant infections (25.0%), infections (18.2%), vascular disease (13.6%) and cancer (4.5%). Mortality was associated with higher SLEDAI, Katz, damage indexes and comorbidities. Of the 1610 patients included, 44.6% were Caucasian, 44.5% Mestizo, 8.1% Amerindian and 1.2% Afro-Latin American. Mestizo patients had higher male representation, low socioeconomic status, more inadequate medical coverage, fewer formal years of education and shorter disease duration. Polyadenopathies and Raynaud's phenomenon were more frequent in Caucasians. In the logistic regression analysis higher damage index (OR 1.28, CI 95% 1.02-1.61, p = 0.03) remained associated to mestizo ethnicity. CONCLUSIONS: This study represents the largest number of adult patients with SLE studied in Argentina. Caucasian patients were differentiated by having Raynaud's phenomenon and polyadenopathy more frequently, while patients of Mestizo origin had higher damage indexes.


Asunto(s)
Etnicidad , Lupus Eritematoso Sistémico , Argentina/epidemiología , Estudios Transversales , Femenino , Humanos , Lupus Eritematoso Sistémico/complicaciones , Masculino , Fenotipo , Índice de Severidad de la Enfermedad
3.
Rev Sci Instrum ; 92(5): 053703, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243258

RESUMEN

The performance of time-resolved photoemission experiments at fs-pulsed photon sources is ultimately limited by the e-e Coulomb interaction, downgrading energy and momentum resolution. Here, we present an approach to effectively suppress space-charge artifacts in momentum microscopes and photoemission microscopes. A retarding electrostatic field generated by a special objective lens repels slow electrons, retaining the k-image of the fast photoelectrons. The suppression of space-charge effects scales with the ratio of the photoelectron velocities of fast and slow electrons. Fields in the range from -20 to -1100 V/mm for Ekin = 100 eV to 4 keV direct secondaries and pump-induced slow electrons back to the sample surface. Ray tracing simulations reveal that this happens within the first 40 to 3 µm above the sample surface for Ekin = 100 eV to 4 keV. An optimized front-lens design allows switching between the conventional accelerating and the new retarding mode. Time-resolved experiments at Ekin = 107 eV using fs extreme ultraviolet probe pulses from the free-electron laser FLASH reveal that the width of the Fermi edge increases by just 30 meV at an incident pump fluence of 22 mJ/cm2 (retarding field -21 V/mm). For an accelerating field of +2 kV/mm and a pump fluence of only 5 mJ/cm2, it increases by 0.5 eV (pump wavelength 1030 nm). At the given conditions, the suppression mode permits increasing the slow-electron yield by three to four orders of magnitude. The feasibility of the method at high energies is demonstrated without a pump beam at Ekin = 3830 eV using hard x rays from the storage ring PETRA III. The approach opens up a previously inaccessible regime of pump fluences for photoemission experiments.

4.
Microsc Microanal ; 26(3): 567-574, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32393416

RESUMEN

Constitutive heterochromatin typically exhibits low gene density and is commonly found adjacent or close to the nuclear periphery, in contrast to transcriptionally active genes concentrated in the innermost nuclear region. In Triatoma infestans cells, conspicuous constitutive heterochromatin forms deeply stained structures named chromocenters. However, to the best of our knowledge, no information exists regarding whether these chromocenters acquire a precise topology in the cell nuclei or whether their 18S rDNA, which is important for ribosome function, faces the nuclear center preferentially. In this work, the spatial distribution of fluorescent Feulgen-stained chromocenters and the distribution of their 18S rDNA was analyzed in Malpighian tubule cells of T. infestans using confocal microscopy. The chromocenters were shown to be spatially positioned relatively close to the nuclear periphery, though not adjacent to it. The variable distance between the chromocenters and the nuclear periphery suggests mobility of these bodies within the cell nuclei. The distribution of 18S rDNA at the edge of the chromocenters was not found to face the nuclear interior exclusively. Because the genome regions containing 18S rDNA in the chromocenters also face the nuclear periphery, the proximity of the chromocenters to this nuclear region is not assumed to be associated with overall gene silencing.


Asunto(s)
Núcleo Celular , Heterocromatina , Triatoma/genética , Animales , Cromatina , ADN Ribosómico , Masculino
5.
Rev Sci Instrum ; 91(1): 013109, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32012554

RESUMEN

Time-resolved photoemission with ultrafast pump and probe pulses is an emerging technique with wide application potential. Real-time recording of nonequilibrium electronic processes, transient states in chemical reactions, or the interplay of electronic and structural dynamics offers fascinating opportunities for future research. Combining valence-band and core-level spectroscopy with photoelectron diffraction for electronic, chemical, and structural analyses requires few 10 fs soft X-ray pulses with some 10 meV spectral resolution, which are currently available at high repetition rate free-electron lasers. We have constructed and optimized a versatile setup commissioned at FLASH/PG2 that combines free-electron laser capabilities together with a multidimensional recording scheme for photoemission studies. We use a full-field imaging momentum microscope with time-of-flight energy recording as the detector for mapping of 3D band structures in (kx, ky, E) parameter space with unprecedented efficiency. Our instrument can image full surface Brillouin zones with up to 7 Å-1 diameter in a binding-energy range of several eV, resolving about 2.5 × 105 data voxels simultaneously. Using the ultrafast excited state dynamics in the van der Waals semiconductor WSe2 measured at photon energies of 36.5 eV and 109.5 eV, we demonstrate an experimental energy resolution of 130 meV, a momentum resolution of 0.06 Å-1, and a system response function of 150 fs.

6.
Water Res ; 145: 153-161, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30142513

RESUMEN

In this work, water-based paint (WBP) wastewater was treated using a natural coagulant, Moringa oleifera aqueous extract (MOAE), fortified with Ca2+ (from nitrate and chloride salts). In order to improve the quality of the treated wastewater and render it suitable for disposal, an electrolytic flow process was associated with the wastewater treatment using a filter-press reactor with a boron doped diamond (BDD) electrode. The feasibility of the treatment was evidenced by the reuse of the treated wastewater in the production of a new paint (manufactured by the company supplying the raw wastewater), whose quality was compatible with the water used by the manufacturer. The best conditions for the coagulation-flocculation process involved the use of 80 mL of MOAE (50 g/L of MO and 0.125 mol/L of Ca2+) for every 1.0 L of wastewater at pH 6.5. The limiting current density (35 mA/cm2) and an electrolysis time of 90 min (charge passed of 3.68 A h/L) were used in the electrochemical treatment. Biotoxicity assays using the brine shrimp Artemia salina revealed that the mortality (in %) of microcrustaceans was reduced from 100% (raw wastewater) to only 11% at the end of the electrolysis process, in addition to eliminating the strong odor and 85% of the organic load. Moreover, microbiological tests showed that the number of mesophiles decreased by more than six orders of magnitude and there was no growth of thermotolerant coliforms (TC).


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Técnicas Electroquímicas , Electrodos , Electrólisis , Floculación , Pintura , Eliminación de Residuos Líquidos , Aguas Residuales
7.
Micron ; 90: 87-96, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27632071

RESUMEN

A previous study has not revealed the participation of a mucous component in the cocoon wall of the solitary bee, Lithurgus chrysurus, differing from the cocoon structure reported for many other bee species. However, uncertainty remains, because only the median and rear zones of this cocoon type have thus far been analyzed. Here, we studied the front zone of this cocoon, searching its components and their organization, to fill this knowledge gap. Topochemical assays, polarization microscopy and Fourier transform-infrared (FT-IR) microspectroscopy were used to study cross sections from L. chrysurus cocoon. Three main layers differing in structural organization were found to compose the cocoon wall. Silk fibroins were assumed to constitute the filamentous threads of the inner and outer layers and the laminar structure of the intermediate layer. Deduced from its topochemical properties and FT-IR spectral signature, a foamy material containing mucin glycoproteins and carboxylated acid glycosaminoglycans was found in the intermediate layer. FT-IR analysis using a Savitzky-Golay 2nd-derivative and absence of linear dichroism and birefringence phenomena suggest that a random-coil secondary structure predominates in the foam component. Co-existence of α-helical and ß-sheet conformations is also hypothesized for the fibroin component of this cocoon. It is thus concluded that in addition to fibroin elements, a mucous component, likely contributed by a Malpighian tubule secretion, integrates the composition of the front zone of the cocoon wall of L. chrysurus. In addition, the FT-IR analysis of the inner layer silk of this cocoon suggests significant differences in comparison to the silk fibroins of the silkworm, and some minor spectral differences in comparison to published data on the honeybee silk, with respect to protein secondary structure.


Asunto(s)
Abejas/química , Fibroínas/química , Animales , Abejas/fisiología , Mucinas/química , Estructura Secundaria de Proteína , Seda/química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Water Res ; 101: 467-475, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27295621

RESUMEN

This paper describes and discusses an investigation into the treatment of paint manufacturing wastewater (water-based acrylic texture) by coagulation (aluminum sulfate) coupled to electrochemical methods (BDD electrode). Two proposals are put forward, based on the results. The first proposal considers the feasibility of reusing wastewater treated by the methods separately and in combination, while the second examines the possibility of its disposal into water bodies. To this end, parameters such as toxicity, turbidity, color, organic load, dissolved aluminum, alkalinity, hardness and odor are evaluated. In addition, the proposal for water reuse is strengthened by the quality of the water-based paints produced using the wastewater treated by the two methods (combined and separate), which was evaluated based on the typical parameters for the quality control of these products. Under optimized conditions, the use of the chemical coagulation (12 mL/L of Al2(SO4)3 dosage) treatment, alone, proved the feasibility of reusing the treated wastewater in the paint manufacturing process. However, the use of the electrochemical method (i = 10 mA/cm(2) and t = 90 min) was required to render the treated wastewater suitable for discharge into water bodies.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Técnicas Electroquímicas , Electrodos , Oxidación-Reducción , Pintura , Contaminantes Químicos del Agua , Purificación del Agua
9.
Cell Tissue Res ; 362(1): 177-85, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25866201

RESUMEN

Entheses are specialized biological structures that functionally anchor tendons to bones. The complexity, mechanical characteristics and properties of the entheses, particularly those related to exercise, mechanical load and pathologies, have been extensively analyzed; however, the macromolecular organization of the enthesis fibers, as assessed by polarization microscopy, has not yet been investigated. Morphological and optical anisotropy characteristics, such as birefringence, linear dichroism (LD) and differential interference contrast (DIC-PLM) properties, are thus analyzed in this study of a healthy adult mouse calcaneal tendon-bone enthesis. The molecular and supramolecular order of collagen and GAGs was determined for the collagen bundles of this enthesis. Based on a birefringence plot pattern as well as on metachromasy and linear dichroism after toluidine blue staining at pH 4.0, a similarity between the calcaneal tendon-bone enthesis and cartilage during ossification may be assumed. This similarity is assumed to favor the adequacy of this enthesis to support a compressive load. Considering that the collagen-proteoglycan complexes and the enthesis fibers themselves have a chiral nature, these structures could be acting via reciprocal signaling with the cellular environment of the enthesis.


Asunto(s)
Anisotropía , Mediadores de Inflamación/inmunología , Fenómenos Ópticos , Animales , Ratones , Ingeniería de Tejidos
10.
J R Army Med Corps ; 151(2): 101-4, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16097115

RESUMEN

OBJECTIVES: To examine the profile of medical morbidity and the role of the physician in modern conflict. METHODS: Retrospective survey of admission records at a British Military Field Hospital on operational duty in Southern Iraq. RESULTS: 62.5% of 4870 admissions to the Field Hospital in Shaibah during the first 12 months of military operations in Iraq were under the care of physicians. Of these 1531 (31.4%) were due to diarrhoea and vomiting (D&V) and 764 (15.7%) due to heat illness. The incidence of heat illness rose with ambient temperature, but soldiers were more likely to be admitted with heat illness shortly after arrival in theatre than when fully acclimatised. There was also a steady flow of admissions with a broad spectrum of medical pathology requiring the clinical skills of a general physician. CONCLUSIONS: A general physician is a necessary part of the clinical team in modern conflict. The incidence of D&V and of heat illness on military operations remains high. Planners for any operation in tropical climates should take this into consideration and put preventative measures into place early.


Asunto(s)
Personal Militar , Rol del Médico , Guerra , Encuestas de Atención de la Salud , Hospitales Militares/estadística & datos numéricos , Humanos , Irak , Admisión del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Reino Unido
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