Fractional Wigner crystal in the helical Luttinger liquid

The properties of the strongly interacting edge states of two dimensional topological insulators in the presence of two particle backscattering are investigated. We find an anomalous behavior of the density-density correlation functions, which show oscillations that are neither of Friedel nor of Wigner type: they instead represent a Wigner crystal of fermions of fractional charge e/2, with e the electron charge. By studying the Fermi operator, we show that the state characterized by such fractional oscillations still bears the signatures of spin momentum locking. Finally, we compare the spin-spin correlation functions and the density-density correlation functions to argue that the fractional Wigner crystal is characterized by a non trivial spin texture.Comment: 5 pages, 2 figure

Immunolocalization of G protein-coupled estrogen receptor in the rat epididymis

Background Estrogen plays an important role in male reproduction, and males lacking estrogen signaling in the reproductive tissues are infertile. Estrogen signaling is mediated via two nuclear receptors, ERα and ERβ, but it was recently found that a G protein-coupled estrogen receptor (GPER) is present in the testis. It is believed that GPER is a membrane form of the estrogen receptor and mediates non-classical estrogen signaling. However, the cellular localization of GPER in the epididymis is unknown. Therefore, the objective of this study was to determine the cellular and regional expression of GPER in the rat epididymis. Findings To localize expression, immunohistochemistry (IHC) was performed using fixed epididymal tissue. Three strains and ages of rats were used to identify whether GPER expression is strain or age specific. Our results are the first to demonstrate immunostaining of GPER in epididymal epithelial cells. Expression was highest near the apical membrane followed by the cytoplasm, consistent with a membrane bound receptor. The highest expression in adult rats was observed in corpus followed by cauda. Western blotting analysis of epididymal tissues from Sprague Dawley rats confirmed specificity of the antibody and regional expression. Conclusions Expression of GPER in the corpus and cauda suggests a role for non-classical estrogen signaling in sperm maturation in the corpus, and sperm protection/storage in the cauda. GPER expression pre-pubertally suggests that estrogen may have a role in epithelial cell development in addition to regulation of adult function

Inelastic and elastic collision rates for triplet states of ultracold strontium

We report measurement of the inelastic and elastic collision rates for ^{88}Sr atoms in the (5s5p)^3P_0 state in a crossed-beam optical dipole trap. This is the first measurement of ultracold collision properties of a ^3P_0 level in an alkaline-earth atom or atom with similar electronic structure. Since the (5s5p)^3P_0 state is the lowest level of the triplet manifold, large loss rates indicate the importance of principle-quantum-number-changing collisions at short range. We also provide an estimate of the collisional loss rates for the (5s5p){^3P_2} state.Comment: 4 pages 5 figure

Cambios paleoambientales desde el Pleistoceno tardío hasta el Holoceno medio basados en el registro de diatomeas en la Salina del Bebedero (San Luis, Argentina)

This study analyzes the environmental changes that occurred in the western sector of the San Luis province (Argentina) during the Late Pleistocene to Middle Holocene period (approximately 12,600 to 3,600 years BP). The information provided by diatoms as paleobiological indicators is used for this analysis. We examined the lower 5 meters of the 10-meter-long SBIII core, which was recovered from the endorheic and hypersaline shallow lake known as Salina del Bebedero (33°20’S-66°45’W, 380 m a.s.l.). The observed peaks of relative abundance of the planktonic diatom Cyclotella choctawhatcheeana suggest episodes of substantial water supply to the shallow lake from the Andes mountains via the Desaguadero river. These episodes were interspersed with periods of low water levels, resulting in very shallow to marsh environments characterized by the presence of epiphytic and benthic diatoms. Furthermore, we discuss and integrate the inferred paleoenvironmental information obtained from the diatom records, along with data from other proxies such as pollen and sedimentology. This integration aims to enhance the previously developed paleoenvironmental model for the region, covering the period between approximately 12,600 and 3,600 years BP. Overall, this research significantly contributes to the understanding of diatom assemblages in hypersaline lacustrine systems of the eastern Andes throughout the studied period, revealing the importance of certain taxa as indicators of wetter conditions during the early Holocene and in more recent stages within this timeframe. Additionally, this study aims to expand our existing knowledge of diatoms biodiversity in this province.Este trabajo aporta herramientas de análisis para la comprensión de los cambios ambientales ocurridos en el sector occidental de la provincia de San Luis (Argentina) entre el periodo del Pleistoceno tardío y el Holoceno medio (ca. 12.600 a ca. 3.600 años AP), utilizando la información provista por diatomeas, como indicadores paleobiológicos. Se analizó la mitad inferior del testigo SBIII (10 a 5 m) obtenido en la cuenca endorreica salino-lacustre Salina del Bebedero (33° 20′ S; 66° 45′ O; 380 (m s.n.m.). Los picos de mayor abundancia relativa de la especie planctónica Cyclotella choctawhatcheeana sugieren episodios de gran aporte de agua a la laguna, procedente de la Cordillera de los Andes a través del río Desaguadero. Estos episodios estuvieron intercalados por periodos con bajos niveles lacustres (ambientes someros o palustres) caracterizados por la presencia de diatomeas epifíticas y bentónicas y se identificaron intervalos donde no se encontraron diatomeas. También discutimos y articulamos la información paleoambiental inferida para el período comprendido entre ca. 12.600 y 3.600 años AP, a partir de los registros de diatomeas, con la información disponible de otros proxies (polen y sedimentología), con el fin de mejorar el modelo paleoambiental generado previamente para la región. Este trabajo amplía el conocimiento de ensambles de diatomeas en sistemas lacustres hipersalinos de los Andes orientales durante el periodo estudiado, revelando la importancia de algunos taxones como indicadores de condiciones más húmedas durante el inicio del Holoceno y en etapas más recientes dentro de este periodo y, además, este estudio, profundiza los conocimientos existentes sobre la biodiversidad diatomológica en esta provincia

Repumping and spectroscopy of laser-cooled Sr atoms using the (5s5p)3P2 - (5s4d)3D2 transition

We describe repumping and spectroscopy of laser-cooled strontium (Sr) atoms using the (5s5p)3P2 - (5s4d)3D2 transition. Atom number in a magneto-optical trap is enhanced by driving this transition because Sr atoms that have decayed into the (5s5p)3P2 dark state are repumped back into the (5s2)1S0 ground state. Spectroscopy of 84Sr, 86Sr, 87Sr, and 88Sr improves the value of the (5s5p)3P2 - (5s4d)3D2 transition frequency for 88Sr and determines the isotope shifts for the transition.Comment: 4 pages, 5 figure

131I therapy for hyperthyroidism and consequent appearing of anaplastic carcinoma of the thyroid: simple case-report or real pathophysiologic link?

BACKGROUND 131I is usually employed for the therapy of hyperfunctioning thyroid diseases. This β-emitting radioisotope acts releasing its radiations in small tissue volumes, but it is mandatory to consider, also for the small doses, the carcinogenic risk, well documented with the high 131I dosages used to cure differentiated thyroid cancers. METHODS We describe a case of anaplastic thyroid carcinoma appeared 4 years after therapy with 131I for Graves' disease. The patient was treated both surgically and with thyonamides for Graves' disease 20 years before; thereafter she underwent simple nephrectomy owing to Grawitz disease. After some years of well being, she was treated with 131I for a relapse of Graves' disease. Four years later, she was treated with interleukin-2 and TNF-α, owing to distant metastases (pancreas, liver and lung) of Grawitz cancer. Some months later, because of a rapid enlargement of the thyroid gland, she was thyroidectomized and anaplastic thyroid cancer was histologically documented. DISCUSSION AND CONCLUSIONS It is very difficult to investigate the possible transformation of a benign thyroid lesion to a malignant one, and data from the literature are conflicting. Fractioned doses of 131I are known to induce less cancers than high doses: they allow DNA to repair. Nevertheless, in patients with altered or non valid genetic repair's mechanisms (i.e. patients with p53 mutations) and, for this reason, prone to develop cancers, even low doses of 131I can induce carcinogenetic effects. In a patient with a history of cancer, who subsequently develops hyperthyroidism, even low doses of 131I can induce anaplastic thyroid cancer; in these subjects, therefore, other treatments than 131I could be preferred for the therapy of Graves' disease. In our peculiar case, moreover, some studies have noteworthy demonstrated that certain cytokines (IL-1, TGF-β1 e TNF-α) can, rather than inhibit, induce anaplastic thyroid cancer cells to grow

Sylloge Fungorum Omnium Hucusque Cognitorum : Vol. XX. Index iconum fungorum

Sylloge Fungorum Omnium Hucusque Cognitorum es una importante obra micológica que consta de 26 volúmenes compilada por Pier Andrea Saccardo (1845-1920), quien fuera un micólogo y botánico italiano. Esta importante obra de taxonomía de hongos (escrita entre 1882 y 1890) es una lista con todos los nombres científicos utilizados y una breve descripción de los hongos. Estas descripciones siguen siendo referencias para los taxónomos actuales. Esta importante colección se encuentra depositada en el Instituto Spegazzini gracias a la generosa donación que hiciera el principal discípulo de Saccardo, el Dr. Carlos Spegazzini, y constituye la única colección de su tipo disponible en América del Sur.Material digitalizado en SEDICI gracias a la colaboración del Instituto de Botánica "Dr. Carlos Spegazzini" (Facultad de Ciencias Naturales y Museo, UNLP).Instituto de Botánica "Dr. Carlos Spegazzini

A Feature-Pooling and Signature-Pooling Method for Feature Selection for Quantitative Image Analysis: Application to a Radiomics Model for Survival in Glioma

We proposed a pooling-based radiomics feature selection method and showed how it would be applied to the clinical question of predicting one-year survival in 130 patients treated for glioma by radiotherapy. The method combines filter, wrapper and embedded selection in a comprehensive process to identify useful features and build them into a potentially predictive signature. The results showed that non-invasive CT radiomics were able to moderately predict overall survival and predict WHO tumour grade. This study reveals an associative inter-relationship between WHO tumour grade, CT-based radiomics and survival, that could be clinically relevant

Sylloge Fungorum Omnium Hucusque Cognitorum : Vol. XIX. Index iconum fungorum

Sylloge Fungorum Omnium Hucusque Cognitorum es una importante obra micológica que consta de 26 volúmenes compilada por Pier Andrea Saccardo (1845-1920), quien fuera un micólogo y botánico italiano. Esta importante obra de taxonomía de hongos (escrita entre 1882 y 1890) es una lista con todos los nombres científicos utilizados y una breve descripción de los hongos. Estas descripciones siguen siendo referencias para los taxónomos actuales. Esta importante colección se encuentra depositada en el Instituto Spegazzini gracias a la generosa donación que hiciera el principal discípulo de Saccardo, el Dr. Carlos Spegazzini, y constituye la única colección de su tipo disponible en América del Sur.Material digitalizado en SEDICI gracias a la colaboración del Instituto de Botánica "Dr. Carlos Spegazzini" (Facultad de Ciencias Naturales y Museo, UNLP).Instituto de Botánica "Dr. Carlos Spegazzini