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1.
Sci Adv ; 6(4): eaay2169, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32010785

RESUMO

The coexistence of cultural identities and their interaction is a fundamental topic of social sciences that is not easily addressed in prehistory. Differences in mortuary treatment can help approach this issue. Here, we present a multi-isotope study to track both diet and mobility through the life histories of 32 broadly coeval Late Neolithic individuals interred in caves and in megalithic graves of a restricted region of northern Iberia. The results show significant differences in infant- and child-rearing practices, in subsistence strategies, and in landscape use between burial locations. From this, we posit that the presence of communities with distinct lifestyles and cultural backgrounds is a primary reason for Late Neolithic variability in burial location in Western Europe and provides evidence of an early "them and us" scenario. We argue that this differentiation could have played a role in the building of lasting structures of socioeconomic inequality and, occasionally, violent conflict.


Assuntos
Antropologia Cultural , Cultura , Isótopos , Ciências Sociais , Isótopos de Carbono/análise , Cavernas , Meio Ambiente , Europa (Continente) , Humanos , Isótopos de Nitrogênio/análise , Plantas
2.
Appl Radiat Isot ; 154: 108863, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31513990

RESUMO

The nuclide 231Pa is a member of the 235U decay chain. It is a complex alpha emitter with 25 identified alpha emissions. Formerly published alpha-particle emission probabilities were derived from measurements taken with magnetic spectrometers. This work presents the first measurements made with semiconductor detectors. High-resolution alpha-particle spectrometry was carried out at CIEMAT and JRC using ion-implanted planar silicon detectors. Alpha-particle emission probabilities of 23 transitions were derived from deconvolutions of the spectra. For the major lines, uncertainties are lower than 1%, a significant improvement to existing data. The new data set will allow a more accurate evaluation of the decay scheme of 231Pa.

3.
Appl Radiat Isot ; 125: 196-202, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28476016

RESUMO

High-resolution alpha-particle spectrometry was performed to determine the main alpha-particle emission probabilities in the decay of 226Ra. Thin, homogeneous sources were prepared by electrodeposition on stainless steel disks. Alpha spectra with an energy resolution of 20keV were obtained in three laboratories and analysed with different deconvolution algorithms. In two set-ups, a magnet system was used to deflect conversion electrons to avoid their coincidental detection with the alpha particles. Spectra taken at close range without a magnet system yielded biased results which cannot be fully compensated by statistical corrections for coincidence summing. The derived emission probabilities of the three main alpha decays are 94.07 (1)%, 5.93 (1)%, and 0.0059 (15)%, respectively. They are in excellent agreement with calculated values derived from the P(γ+ce) decay scheme balance, which solves the existing discrepancy problem with two previous direct measurements published in literature.

4.
Ann Vasc Surg ; 9(1): 80-6, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7703066

RESUMO

The purpose of this study was to determine the efficacy of intravascular photodynamic therapy (PDT) to prevent the development of intimal hyperplasia. Anesthetized New Zealand white rabbits underwent placement of Fogarty balloon catheters introduced via femoral artery cutdowns. Catheters were passed retrograde 10 cm into the lower abdominal aorta, inflated six times, and withdrawn toward the inguinal ligament. Rabbits were then randomly assigned to one of the following groups: group 1, drug with no light; group 2, no drug with 240 joules of light; group 3, drug plus 120 joules of light; or group 4, drug plus 240 joules of light. Uninjured carotid arteries served as negative control vessels (N) and injured but non-PDT-treated iliac artery segments served as positive controls (P). Porfimer sodium (photofrin) was administered in a dose of 5.0 mg/kg. Light was provided by a fiberoptic probe with a 1 cm cylindric diffuser attached to an argon pumped dye laser tuned to 630 nm to provide 1 W of laser light for 120 or 240 seconds. One month after PDT, rabbits were killed, perfusion fixed with glutaraldehyde, and vessels removed and examined microscopically. Intimal thickness (mean +/- SD) was calculated and expressed as ratios of the intima/media at four equal positions. Results for N, P, and groups 1, 2, 3, and 4 were 0.02 +/- 0.00, 1.18 +/- 0.71, 0.76 +/- 0.33, 0.96 +/- 0.43, 0.14 +/- 0.22, and 0.36 +/- 0.16, respectively. Intimal thickness was significantly reduced in groups 3 and 4 when compared with P, group 1, and group 2 (p < 0.001, ANOVA). These results showed that intravascular PDT was effective in reducing intimal hyperplasia following arterial injury. This may be a practical method of delivering light for PDT.


Assuntos
Fotoquimioterapia/métodos , Túnica Íntima/patologia , Animais , Éter de Diematoporfirina/uso terapêutico , Tecnologia de Fibra Óptica , Hiperplasia , Terapia a Laser , Fármacos Fotossensibilizantes/uso terapêutico , Coelhos
5.
J Pharm Sci ; 81(6): 577-80, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1522498

RESUMO

The pi (hydrophobic constant) values for 16 parent azoles (pyrrole, imidazole, pyrazole, four triazoles, two tetrazoles, indole, benzimidazole, 1H- and 2H-indazoles, 1H- and 2H-benzotriazoles, and carbazole) were calculated from the logarithms of the capacity factors (log k') determined by HPLC. The values thus obtained are discussed according to an additive model in which the number and position of pyridinelike nitrogen atoms and the annelation effect are considered.


Assuntos
Azóis/análise , Azóis/química , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Análise de Regressão , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
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