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Metallic ferromagnetic transition metal dichalcogenides have emerged as important building blocks for scalable magnetic and memory applications. Downscaling such systems to the ultrathin limit is critical to integrate them into technology. Here, we achieved layer-by-layer control over the transition metal dichalcogenide Cr1.6Te2 by using pulsed laser deposition, and we uncovered the minimum critical thickness above which room-temperature magnetic order is maintained. The electronic and magnetic structures are explored experimentally and theoretically, and it is shown that the films exhibit strong in-plane magnetic anisotropy as a consequence of large spin-orbit effects. Our study elucidates both magnetic and electronic properties of Cr1.6Te2 and corroborates the importance of intercalation to tune the magnetic properties of nanoscale materials' architectures.
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BACKGROUND: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. METHODS: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. RESULTS: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. CONCLUSIONS: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception.
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Neoplasias Colorretais , Emergências , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Estudos Prospectivos , Complicações Pós-Operatórias/etiologia , Anastomose Cirúrgica/métodos , Neoplasias Colorretais/cirurgiaRESUMO
The relation between crystal symmetries, electron correlations and electronic structure steers the formation of a large array of unconventional phases of matter, including magneto-electric loop currents and chiral magnetism1-6. The detection of such hidden orders is an important goal in condensed-matter physics. However, until now, non-standard forms of magnetism with chiral electronic ordering have been difficult to detect experimentally7. Here we develop a theory for symmetry-broken chiral ground states and propose a methodology based on circularly polarized, spin-selective, angular-resolved photoelectron spectroscopy to study them. We use the archetypal quantum material Sr2RuO4 and reveal spectroscopic signatures that, despite being subtle, can be reconciled with the formation of spin-orbital chiral currents at the surface of the material8-10. As we shed light on these chiral regimes, our findings pave the way for a deeper understanding of ordering phenomena and unconventional magnetism.
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PURPOSE: Pneumatosis intestinalis is a radiological finding with incompletely understood pathogenesis. To date, there are no protocols to guide surgical intervention. METHODS: A systematic review of literature, according to PRISMA criteria, was performed. Medline and PubMed were consulted to identify articles reporting on the items "emergency surgery, pneumatosis coli, and pneumatosis intestinalis" from January 2010 up to March 2022. This study has not been registered in relevant databases. RESULTS: A total of 1673 patients were included. The average age was 67.1 ± 17.6 years. The etiology was unknown in 802 (47.9%) patients. Hemodynamic instability (246/1673-14.7% of the patients) was associated with bowel ischemia, necrosis, or perforation (p = 0.019). Conservative management was performed in 824 (49.2%) patients. Surgery was performed 619 (36.9%) times, especially in unstable patients with bowel ischemia signs, lactate levels greater than 2 mmol/L, and PVG (p = 0.0026). In 155 cases, surgery was performed without pathological findings. CONCLUSIONS: Many variables should be considered in the approach to patients with pneumatosis intestinalis. The challenge facing the surgeons is in truly identifying those who really would benefit and need surgical intervention. The watch and wait policy as a first step seems reasonable, reserving surgery only for patients who are unstable or with high suspicion of bowel ischemia, necrosis, or perforation.
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van der Waals materials provide a versatile toolbox for the emergence of new quantum phenomena and fabrication of functional heterostructures. Among them, the trihalide VI3 stands out for its unique magnetic and structural landscape. Here we investigate the spin and orbital magnetic degrees of freedom in the layered ferromagnet VI3 by means of temperature-dependent X-ray absorption spectroscopy and X-ray magnetic circular and linear dichroism. We detect localized electronic states and reduced magnetic dimensionality, due to electronic correlations. We furthermore provide experimental evidence of (a) an unquenched orbital magnetic moment (up to 0.66(7) µB/V atom) in the ferromagnetic state and (b) an instability of the orbital moment in the proximity of the spin reorientation transition. Our results support a coherent picture where electronic correlations give rise to a strong magnetic anisotropy and a large orbital moment and establish VI3 as a prime candidate for the study of orbital quantum effects.
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Se revisan los argumentos genéticos, experimentales, fisiopatológicos y clínicos que apoyan la relación entre hiperglicemia y complicaciones microvasculares de la diabetes. Se postula que su presencia y progresión tengan una base genética, modificable en base a un estricto control de la excursión glicémica diaria; se definen los tipos de pacientes en los que se debe intentarlo prioritariamente, con fines preventivos. Si bien los parámetros bioquímicos aceptados de buen control de la diabetes, glicemia pre y postprandiales y hemoglobina glicosilada, deben sobreponerse con los de un individuo normal, las metas a alcanzar deben plantearse individualmente, tomando en consideración las condiciones intelectuales, psicológicas y económico-sociales de cada paciente. Se analizan los métodos de control a largo y corto, incluyendo hemoglobina glicosilada, glicosuria ocasional o fraccionada, glicemias en ayunas, postprandial y autocontrol mediante cintas reactivas, sus limitaciones y diferentes indicaciones en las diabetes mellitus de tipo I y II. Por último se comentan brevemente las circunstancias que deben conciliarse para llegar a un tratamiento insulínico intensificado y se presentan a título de ejemplo, algunos esquemas
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Humanos , Masculino , Feminino , Diabetes Mellitus/prevenção & controle , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/prevenção & controle , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/terapia , Hiperglicemia/complicações , Insulina/uso terapêuticoAssuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Feminino , Tiroxina/uso terapêutico , Tri-Iodotironina/uso terapêutico , Hipotireoidismo/tratamento farmacológico , Sela Túrcica/patologia , Tiroxina/sangue , Tireotropina/sangue , Testes de Campo Visual , Hipotireoidismo/fisiopatologiaRESUMO
En base a antecedentes epidemiológicos y evolutivos de la diabetes mellitus, se discuten los valores de la prueba de tolerancia a la glucosa (PTG) que permiten el diagnóstico de la enfermedad. Se presentan las cifras de la PTG para el diagnóstico de diabetes mellitus y de tolerancia alterada a la glucosa, recomendadas por el National Diabetes Data Group y por la OMS. Se llama la atención que el grupo intermedio entre normalidad y enfermedad, denominado tolerancia alterada a la glucosa, se debe a la imprecisión de la PTG; pero que en futuro, con método de estudio más perfeccionados se obtendrán diagnósticos más exactos