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The aim of this research was to propose methodological changes in the teaching-learning process of the judo technique Deashi-harai, pointing out the most frequent technical errors committed during its performance and also its action sequences. We carried out an observational study with the participation of fifty novice judokas at the University of Vigo. We recorded them while performing the Deashi-harai technique after a previous training of four months. Data obtained were evaluated using descriptive statistics and T-patterns analysis. Thus, we indentified: a) some typical inaccuracies during the technique execution and b) a number of chained errors affecting the imbalance of the body, the position of the right foot, the sweeping action and the action of the arms. These findings allowed us to suggest some motor tasks to correct the identified inaccuracies, the sequential actions to ensure the success of the execution and several recommendations for the proper use of the feedback.

We present the nanoheteroepitaxial growth of gallium arsenide (GaAs) on nano-patterned silicon (Si) (001) substrates fabricated using a CMOS technology compatible process. The selective growth of GaAs nano-crystals (NCs) was achieved at 570 °C by MOVPE. A detailed structure and defect characterization study of the grown nano-heterostructures was performed using scanning transmission electron microscopy, x-ray diffraction, micro-Raman, and micro-photoluminescence (μ-PL) spectroscopy. The results show single-crystalline, nearly relaxed GaAs NCs on top of slightly, by the SiO2-mask compressively strained Si nano-tips (NTs). Given the limited contact area, GaAs/Si nanostructures benefit from limited intermixing in contrast to planar GaAs films on Si. Even though a few growth defects (e.g. stacking faults, micro/nano-twins, etc) especially located at the GaAs/Si interface region were detected, the nanoheterostructures show intensive light emission, as investigated by μ-PL spectroscopy. Achieving well-ordered high quality GaAs NCs on Si NTs may provide opportunities for superior electronic, photonic, or photovoltaic device performances integrated on the silicon technology platform. [ABSTRACT FROM AUTHOR]

Nano-heteroepitaxial growth of GaAs on Si(001) by metal organic vapor phase epitaxy was investigated to study emerging materials phenomena on the nano-scale of III–V/Si interaction. Arrays of Si nano-tips (NTs) embedded in a SiO2 matrix were used as substrates. The NTs had top Si openings of 50–90 nm serving as seeds for the selective growth of GaAs nano-crystals (NCs). The structural and morphological properties were investigated by high resolution scanning electron microscopy, atomic force microscopy, electron backscatter diffraction, x-ray diffraction, and high resolution scanning transmission electron microscopy. The GaAs growth led to epitaxial NCs featuring a bi-modal distribution of size and morphology. NCs of small size exhibited high structural quality and well-defined {111}–{100} faceting. Larger clusters had less regular shapes and contained twins. The present work shows that the growth of high quality GaAs NCs on Si NTs is feasible and can provide an alternate way to the integration of compound semiconductors with Si micro- and opto-electronics technology. [ABSTRACT FROM AUTHOR]

El cáncer de vesícula es un hallazgo incidental en el 0,5% a 2,3% de todas las colecistectomías por litiasis vesicular. Se debe sospechar en toda tumoración sobre las cicatrices de puertos de trocares. El seguimiento histopatológico postoperatorio es importante para el diagnóstico. Se presenta el cuadro clínico de un paciente sometido a colecistectomía laparoscópica previa (18 meses), con tumoración umbilical recidivánte por cáncer de vesícula.

Context.—: Distinction between Merkel cell carcinoma (MCC) and pulmonary small cell carcinoma (PSmCC) can be challenging, even with the aid of immunohistochemistry (IHC) analysis of CK20 and TTF1, as these tumors occasionally lack classic immunophenotypes (CK20+/TTF1- in MCC and CK20-/TTF1+ in PSmCC)., Objective.—: To evaluate the diagnostic utility of SOX11 and PAX5 IHC for distinguishing MCCs from PSmCCs and compare it with that of CK20 and TTF1 IHC., Design.—: SOX11, PAX5, CK20, and TTF1 expression (pattern, intensity, and proportion of tumor cells expressing protein) was assessed in 31 primary and 16 metastatic MCCs and 20 primary and 9 metastatic PSmCCs., Results.—: SOX11 expression was present in all MCCs and was predominantly strong and diffuse. Only 19% of primary and 38% of metastatic MCCs exhibited diffuse PAX5 expression; none exhibited strong immunoreactivity. Strong and diffuse SOX11 expression was seen in less than 25% of primary and metastatic PSmCCs. PAX5 expression was rare in PSmCCs and was mostly weak and focal/patchy. SOX11 expression in at least 26% of tumor cells, with at least moderate intensity, favored the diagnosis of MCC over PSmCC (P < .001). Furthermore, SOX11 expression was more likely than CK20 expression to be strong or diffuse in sentinel lymph node (SLN) metastases of MCC, indicating that SOX11 is superior to CK20 for detecting tumor deposits in SLNs in MCC., Conclusions.—: Our findings indicate that SOX11 not only is a powerful marker for distinguishing MCCs from PSmCCs, especially when used in conjunction with CK20 and TTF1, but also has utility for screening SLNs in MCC., (© 2023 College of American Pathologists.)

Context.—: Molecularly distinct from cutaneous melanomas arising from sun-exposed sites, acral lentiginous melanomas (ALMs) typically lack ultraviolet-signature mutations, such as telomerase reverse transcriptase (TERT) promoter mutations. Instead, ALMs show a high degree of copy number alterations, often with multiple amplifications of TERT, which are associated with adverse prognosis. The prognostic value of TERT protein expression in acral melanomas, however, is not established., Objective.—: To evaluate the frequency and pattern of TERT immunoreactivity and assess the potential utility of TERT expression as a prognostic indicator in ALMs., Design.—: TERT expression by immunohistochemistry was analyzed in a series of 57 acral and nonacral melanocytic lesions, including 24 primary and 6 metastatic ALMs. Clinical outcome in patients with ALMs by TERT expression was assessed., Results.—: TERT expression was more frequent in ALMs than in nonlentiginous acral melanomas and nonacral cutaneous melanomas, and was absent in acral nevi (P = .01). When present, TERT expression in ALMs was cytoplasmic and more intense than TERT expression in other melanocytic lesions (P = .05) with a higher H-score (P = .01). There was a trend toward decreased overall survival in patients with ALMs with TERT immunoreactivity, but it did not reach statistical significance. Furthermore, no correlation was found between TERT expression and disease-specific survival in patients with ALMs., Conclusions.—: Although TERT protein expression was frequently detected in both primary and metastatic ALMs, TERT immunoreactivity in ALMs did not correlate with survival in our study. Further studies with larger cohorts are needed to elucidate the prognostic value of TERT expression in ALMs.