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经股动脉逆行导丝跨瓣是目前经导管主动脉瓣置换术中最常见的跨瓣方法。该文报道2例主动脉瓣置换术后瓣膜衰败的重度主动脉瓣狭窄患者，导丝逆行跨主动脉瓣难度大，采用穿刺房间隔顺行跨瓣方法成功建立轨道，人工瓣膜经股动脉逆行释放，避免顺行释放可能造成的二尖瓣损伤。术后超声心动图提示人工瓣膜流速、跨瓣压差明显改善，无明显瓣周漏，患者症状明显改善，短期临床效果满意。穿刺房间隔顺行跨瓣对于导丝跨瓣难度大的经导管主动脉瓣置换术患者是一种有效的替代方法。.

三尖瓣反流常继发于肺动脉高压、心房颤动、风湿性瓣膜病和外伤等，常伴有症状性心力衰竭及高死亡率，传统治疗方法为外科手术，但外科手术死亡率较高，且很多患者无法耐受外科手术，故目前尚无安全有效的治疗方法。该文报道1例外科手术高危的重度三尖瓣反流患者，行经股静脉异位三尖瓣介入治疗后临床症状改善，并结合文献分析了异位三尖瓣植入术围手术期注意事项，为临床实践提供参考。.

This work presents an analysis of the ionospheric responses to the solar eclipse that occurred on December 14, 2020, over the Brazilian sector. This event partially covers the south of Brazil, providing an excellent opportunity to study the modifications in the peculiarities that occur in this sector, as the Equatorial Ionization Anomaly (EIA). Therefore, we used the Digisonde data available in this period for two sites, Campo Grande (CG, 20.47° S, 54.60° W, dip ∼23° S) and Cachoeira Paulista (CXP, 22.70° S, 45.01° W, dip ∼35° S), assessing the E, and F regions, and Es layer behaviors. Additionally, a numerical model (MIRE, Portuguese acronym for E Region Ionospheric Model) is used to analyze the E layer dynamics modification around these times. The results show the F1 region disappearance and an apparent electronic density reduction in the E region during the solar eclipse. We also analyzed the total electron content (TEC) maps from the Global Navigation Satellite System (GNSS) that indicate a weakness in the EIA. On the other hand, we observe the rise of the Es layer electron density, which is related to the gravity waves strengthened during solar eclipse events. Finally, our results lead to a better understanding of the restructuring mechanisms in the ionosphere at low latitudes during the solar eclipse events, even though they only partially reached the studied regions.

In the present work, we evaluate a new method for determining a non-perturbed Total Electron Content (TEC) reference to apply on a new version of the disturbance ionosphere index (DIX). This method is based on calculating a 3-hour moving average over the TEC obtained during a given reference day. We compared the proposed method with TEC values obtained from monthly medians and the International Reference Ionosphere (IRI) model to evaluate its performance. The results are presented and discussed in terms of a dispersion coefficient between each method and the averaged TEC from the five quietest days of each month of 2015, over three Brazilian sites. Finally, we calculated the DIX based on the proposed method and compared it with the original DIX values obtained during the St. Patrick’s Day magnetic storm (17-18 March 2015). Differences between the two approaches are discussed, and the results showed that the non-perturbed reference determination could highly influence the quality of the DIX calculation. Keywords: TEC, DIX, Ionospheric Indices, space weather. RESUMO. No presente trabalho, avaliamos um novo metodo para determinar um Conteudo Eletronico Total (TEC) de referencia para aplica-lo em uma nova versao do indice de perturbacao da ionosfera (DIX). Este metodo baseia-se no calculo de uma media movel de 3 horas sobre o TEC obtido durante um determinado dia de referencia. Comparamos o metodo proposto com os valores de TEC obtidos a partir de medianas mensais e do modelo IRI para avaliar o seu desempenho. Os resultados sao apresentados e discutidos em termos de um coeficiente de dispersao entre cada metodo e a media do TEC para os cinco dias mais calmos de cada mes de 2015, em tres localidades brasileiras. Finalmente, calculamos o DIX com base no metodo proposto e o comparamos com os valores de DIX originais obtidos durante a tempestade geomagnetica do dia de St. Patrick (17-18 de marco de 2015). As diferencas entre as duas abordagens sao discutidas, e os resultados mostram que a determinacao do TEC de referencia nao perturbado pode influenciar diretamente a qualidade do indice DIX. Palavras-chave: TEC, DIX, Indices Ionosfericos, clima espacial.

The ROTI index based on the variation of the TEC is used to detect and characterize the ionospheric irregularities. In the present work, we present a comparative study of five different methodologi...

主动脉瓣生物瓣膜的使用期限为8~10年。该文报道1例85岁患者，经导管主动脉瓣置换术（TAVR）后10年因生物瓣衰败行瓣中瓣TAVR手术，手术成功，患者恢复良好。.

Depression is a common and recurrent mental disease, with complex etiology, which is mainly affected by genetic, metabolic and social factors. The specific pathogenesis is still unclear. In recent years, the hypothesis of inflammatory factors related to depression has attracted wide attention of researchers. A large number of clinical experimental studies have shown that depression is related to the increase of proinflammatory factors in central and peripheral blood. The inflammatory factors in peripheral blood can spread in the brain through the way of specific transporters across the blood-brain barrier, and activate or participate in the brain inflammatory response, and ultimately affect the neuronal activity and neurotransmitter release in the emotional regulation area of the brain, which in turn leads to depressive symptoms. This paper summarizes the relationship between inflammatory factors and depression and its possible mechanism, which provides reference for further prevention and control, clinical treatment and scientific research of depression.抑郁症是一种常见且容易复发的精神疾病，其病因复杂，主要由遗传、代谢和社会因素等多方面因素影响，具体的发病机制尚不明确。近年来，有关抑郁症的炎症因子假说引起了研究人员的广泛关注，大量临床实验研究显示抑郁症与中枢和外周血中促炎症因子的增加有关，外周血中炎症因子可通过特异性转运蛋白跨过血脑屏障的方式在脑中扩散，激活或参与脑部炎症反应，最终影响了脑部情绪调节区域的神经元活动和神经递质的释放，进而引发抑郁症状。本文总结归纳了炎症因子与抑郁症的关系及其可能机制，为进一步开展抑郁症预防控制、临床治疗和科学研究提供借鉴。.

In the present work, we evaluate the accuracy of the Solar Quiet Reference Field (SQRF) model for estimating and predicting the geomagnetic solar quiet (Sq) daily field variation in the South America Magnetic Anomaly (SAMA) region. This model is based on the data set of fluxgate magnetometers from 12 magnetic stations of the Embrace Magnetometer Network (Embrace MagNet) from 2010 to 2018. The model predicts the monthly average horizontal field of the geomagnetic quiet (Sq-H) daily variation solving a set of equations for the specified geographic coordinates in terms of the solar cycle activity, the day of the year, and the universal time. We carried out two comparisons between the prediction and observational data of the Sq-H field. The first part attempts to evaluate the accuracy for estimating the Sq-H field over Medianeira (MED, 25.30°S, 54.11°W, dip angle: -33.45°) by using linear interpolation on the SQRF coefficients and compared it with the data collected from April to December in 2018. It worth mentioning that none of the datasets collected at MED is part of the dataset used to build the SQRF model, hence the need to do interpolation. The second part of the analysis attempts to evaluate the accuracy for predicting the quiet daily field variation over Cachoeira Paulista (CXP, 22.70°S, 45.01°W, dip angle: -38.48°). The dataset collected at CXP prior to the period analyzed in the present work is part of the dataset used to build the SQRF model. Thus, the accuracy of the prediction is tested using magnetic data outside the time interval considered in the model. The results of the prediction for both locations show that the outputs from this empirical model present a good agreement with the Sq-H field obtained from the magnetic field data. The accuracy of the SQRF model (high correlation, r>0.9) provides a high potential for estimating and predicting geomagnetic quiet daily field variation for space weather applications, improving the scientific insight and capability of space weather prediction centers to predict the variability of the regular solar quiet field variation as reference conditions, which may include areas with no measurements.

In the present work, we propose and evaluate a new method for the determination of a non-perturbed Total Electron Content (TEC) reference to apply it on a new version of the disturbance ionosphere index (DIX). This method is based on the calculation of a 3-hour moving average over the TEC obtained during a given reference day (named 3hMAQd method). In this context, the reference day is supposed to represent a quiet pattern considering geomagnetic and ionospheric features. To evaluate its performance, we compared the proposed method with TEC values obtained from monthly medians and the International Reference Ionosphere (IRI) model. The results are presented and discussed in terms of a dispersion coefficient between each method and the averaged TEC from the five quietest days of each month of 2015, over three Brazilian sites. Finally, we calculated the new DIX based on our proposed method and compared it with the original DIX values obtained during the extreme space weather event of St. Patrick’s Day magnetic storm (17–18 March 2015). Differences between the two DIX approaches are discussed to show the improvements in new DIX due to the application of the proposed non-perturbed reference. Moreover, results showed that the quality of the DIX calculation can be highly influenced by the non-perturbed reference determination. In this regard, the 3-hour moving average (3hMAQd) method showed to be a quite appropriate technique for the new DIX calculation, besides the 3-hour window matches with ordinary magnetic indices resolution (e.g. Kp and Ksa).

Acute lymphoblastic leukemia (ALL) causes the dysfunction of the systemic blood system and immune system. The etiology and predisposing factors of ALL are unknown. The suppressor of cytokine signaling 1 (SOCS1) and SOCS2 are inhibitors of cytokine signal transduction. Gene polymorphisms of SOCS1 and SOCS2 and their expressions may be related to ALL.A total of 200 ALL patients in our hospital and 200 healthy people were enrolled in ALL group and control group, respectively. Genomic deoxyribonucleic acids (DNAs) and total RNAs were extracted from the peripheral blood of each subject. Gene polymorphisms of SOCS1 at rs33977706, rs243327, and rs33932899 and those of SOCS2 at rs3816997 were amplified by polymerase chain reaction (PCR) and sequenced. Besides, the expression levels of SOCS1 and SOCS2 in ALL patients were detected by real-time fluorescence quantitative PCR.The frequency of the allele C of SOCS1 rs33977706 in ALL group was lower than that in the control group, displaying a significant difference between the two groups (p=0.015). The frequency of allele A of SOCS2 rs3816997 was notably higher in ALL group than that of the control group (p=0.000). In addition, the frequency of CA genotype of SOCS1 rs33977706 in ALL group was markedly lower than that in the control group, showing a significant difference (p=0.000). ALL group had remarkably higher frequencies of AA genotype of SOCS2 rs3816997 (p=0.000) and ACC haplotype of SOCS gene (p=0.000), and lower frequencies of ATG (p=0.026) and CCC (p=0.006) haplotypes. The two loci, SOCS1 rs33932899 and SOCS1 rs243327, were linked to each other (D'=0.781). Moreover, the expression level of SOCS1 in ALL group was lower than that in the control group, in which the expression of the CT genotype of SOCS1 rs243327 was relatively higher (p=0.021). SOCS2 level was lower in ALL group. Particularly, SOCS2 level in ALL patients carrying AC genotype was lower than those carrying AA and CC genotypes (p=0.000). ALL patients carrying CT genotype of SOCS1 rs243327 had shorter period of agranulocytosis (p=0.000), a lower ratio of bone marrow primitive/immature cells (p=0.001), and a higher hemoglobin (Hb) level in blood (p=0.000). The ratio of bone marrow primordial/immature cells was lower in ALL patients with AC genotype of SOCS2 rs3816997 (p=0.038).The expression levels of SOCS1 and SOCS2 are prominently related to ALL, and their polymorphisms are associated with the susceptibility to ALL.

患者男性，70岁，因"活动后气促1周，加重1 d"入院。诊断为重度钙化性主动脉瓣狭窄，中重度二尖瓣反流，心房颤动，纽约心脏协会（NYHA）心功能Ⅳ级，高血压，肝肾功能不全，2型糖尿病，轻度肺气肿。患者入院后在体外膜肺氧合（ECMO）辅助循环下成功实施了经导管主动脉瓣置换术，术后6 h撤离ECMO，未出现并发症，术后13 d顺利出院。经导管主动脉瓣置换术治疗高危主动脉瓣狭窄安全、有效，而ECMO支持可降低手术风险。.

Invar alloys have a wide application owing to its low expansion characteristics. Recently, it is revealed that some Fe-based bulk metallic glasses (BMGs), which have much higher strength than that of traditional Fe-Ni Invar alloys, also have the Invar effect. Combining the low expansion of the Invar effect and the good mechanical properties of Fe-based BMGs has an attractive potential for applications, for which firstly systematic study on the Invar effect of Fe-based BMGs is needed. In this work, the thermal expansion of 14 FeSiPCBM, (Fe,Co)BSiNb, FeNiPC and FeMoPCB BMGs are investigated. The results show all the alloys have the Invar effect, but can be categorized in two types, depending on whether the low expansion occurs in a wide temperature range below the Curie temperature Tc, or in a narrow temperature range near Tc. It is found the former type of alloys have lower Tc and saturation magnetic induction density, i.e., weaker magnetic properties. The substitution of Fe by Co and Ni weakens the Invar effect. These findings are explained based on the characteristics of the amorphous structure and the Bethe-Slater curve. The findings in this paper help to further develop low expansion Fe-based BMGs.

In this work, we use a new version of the Disturbance Ionosphere Index (DIX) to evaluate ionospheric disturbances over the Brazilian region during two intense geomagnetic storms (22 June 2015 and St. Patrick's Day storm). The DIX values were obtained from the deviation of Total Electron Content (TEC) data acquired during the geomagnetically disturbed days in relation to a non-perturbed TEC reference to provide a single and dimensionless value of the ionospheric degree of perturbation during the magnetic events. Moreover, we used F-layer parameters (foF2 and h’F) measured by ionosondes to identify the ionospheric impacts of storm-time electric fields observed as perturbations in the DIX. Our results show that the geomagnetic storms caused large perturbations in the ionosphere as observed by increases/decreases in the TEC over different latitudinal sectors, which were also observed in the foF2, h’F, and DIX values. Therefore, the DIX has shown to be a useful parameter for observing the ionospheric impact under prompt penetration and disturbance dynamo electric field events, as well as to ionospheric disturbances related to the pre-storm period. Finally, from those observations, we found that the DIX resembles the ionosonde measurements, and that it is consistent with the physical processes that occurred during each phase of the geomagnetic storms.

Bulk metallic glasses (BMGs), like other glasses, soften in the super-cooled liquid region (SCLR). Here in this work, surprisingly, a large expansion is reported occurring in the deep SCLR of a Zr 47 Cu 37 Al 8 Ag 8 BMG. Nano-crystals (NCs) are found precipitated during the anomalous expansion of Zr 47 Cu 37 Al 8 Ag 8 , but also in the SCLR of Zr 43 Cu 41 Al 8 Ag 8 that exhibits a conventional softening. It is found that there is a steep composition and density change at the NCs/amorphous matrix transition region in the former alloy, and this transition region exerts a thermal stress of about 0.15 MPa to the surrounding super-cooled liquid (SCL) and drives the soft SCL to expand severely. (Figure presented) IMPACT STATEMENT An anomalous expansion, and particularly a large expansion instead of softening, is reported occurring in the deep SCLR of a Zr-based bulk metallic glass for the first time.

In this work, we present the uncertainties of the empirical model developed to predict the solar quiet regular daily field variation (Sq) over the Brazilian sector called the Solar Quiet Reference Field (SQRF) model. The SQRF is based on the magnetic station records from the Embrace Magnetometer Network (Embrace MagNet) during the solar cycle 24. Although the prediction and the magnetic field records have a good agreement, we observe that each magnetic station shows a random error behavior, propagating small errors in the model. Also, some physical aspects, as tidal winds and ionospheric conductivity, may have influenced our predictions. Thus, these uncertainties in the Sq field can propagate errors and influence geomagnetic indices' calculation by erroneously scaling the geomagnetic disturbances. In this context, we introduce a new approach to derive a ‘real-time’ geomagnetic index based on the SQRF model for the Sq-H field over the South American sector. We analyze one geomagnetic storm event to show that the results have a good representation of the geomagnetic indices. Finally, this analysis yields a new approach to derive the geomagnetic index for space weather applications and studies that requires an Sq field prediction.