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Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of the deuteron (D) flux are presented. The measurements are based on 21×10^{6} D nuclei in the rigidity range from 1.9 to 21 GV collected from May 2011 to April 2021. We observe that over the entire rigidity range the D flux exhibits nearly identical time variations with the p, ^{3}He, and ^{4}He fluxes. Above 4.5 GV, the D/^{4}He flux ratio is time independent and its rigidity dependence is well described by a single power law âR^{Δ} with Δ_{D/^{4}He}=-0.108±0.005. This is in contrast with the ^{3}He/^{4}He flux ratio for which we find Δ_{^{3}He/^{4}He}=-0.289±0.003. Above â¼13 GV we find a nearly identical rigidity dependence of the D and p fluxes with a D/p flux ratio of 0.027±0.001. These unexpected observations indicate that cosmic deuterons have a sizable primarylike component. With a method independent of cosmic ray propagation, we obtain the primary component of the D flux equal to 9.4±0.5% of the ^{4}He flux and the secondary component of the D flux equal to 58±5% of the ^{3}He flux.
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We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.
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We report the properties of primary cosmic-ray sulfur (S) in the rigidity range 2.15 GV to 3.0 TV based on 0.38×10^{6} sulfur nuclei collected by the Alpha Magnetic Spectrometer experiment (AMS). We observed that above 90 GV the rigidity dependence of the S flux is identical to the rigidity dependence of Ne-Mg-Si fluxes, which is different from the rigidity dependence of the He-C-O-Fe fluxes. We found that, similar to N, Na, and Al cosmic rays, over the entire rigidity range, the traditional primary cosmic rays S, Ne, Mg, and C all have sizeable secondary components, and the S, Ne, and Mg fluxes are well described by the weighted sum of the primary silicon flux and the secondary fluorine flux, and the C flux is well described by the weighted sum of the primary oxygen flux and the secondary boron flux. The primary and secondary contributions of the traditional primary cosmic-ray fluxes of C, Ne, Mg, and S (even Z elements) are distinctly different from the primary and secondary contributions of the N, Na, and Al (odd Z elements) fluxes. The abundance ratio at the source for S/Si is 0.167±0.006, for Ne/Si is 0.833±0.025, for Mg/Si is 0.994±0.029, and for C/O is 0.836±0.025. These values are determined independent of cosmic-ray propagation.
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Carbono , Magnésio , Neônio , Enxofre , Fenômenos MagnéticosRESUMO
We present the precision measurements of 11 years of daily cosmic electron fluxes in the rigidity interval from 1.00 to 41.9 GV based on 2.0×10^{8} electrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The electron fluxes exhibit variations on multiple timescales. Recurrent electron flux variations with periods of 27 days, 13.5 days, and 9 days are observed. We find that the electron fluxes show distinctly different time variations from the proton fluxes. Remarkably, a hysteresis between the electron flux and the proton flux is observed with a significance of greater than 6σ at rigidities below 8.5 GV. Furthermore, significant structures in the electron-proton hysteresis are observed corresponding to sharp structures in both fluxes. This continuous daily electron data provide unique input to the understanding of the charge sign dependence of cosmic rays over an 11-year solar cycle.
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We present the precision measurement of 2824 daily helium fluxes in cosmic rays from May 20, 2011 to October 29, 2019 in the rigidity interval from 1.71 to 100 GV based on 7.6×10^{8} helium nuclei collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The helium flux and the helium to proton flux ratio exhibit variations on multiple timescales. In nearly all the time intervals from 2014 to 2018, we observed recurrent helium flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. In the entire time period, we found that below â¼7 GV the helium flux exhibits larger time variations than the proton flux, and above â¼7 GV the helium to proton flux ratio is time independent. Remarkably, below 2.4 GV a hysteresis between the helium to proton flux ratio and the helium flux was observed at greater than the 7σ level. This shows that at low rigidity the modulation of the helium to proton flux ratio is different before and after the solar maximum in 2014.
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Nighteen people at a restaurant experienced dizziness headaches and other discomforts in six days. According to the description method, the time and location distribution were found to be concentrated. A second Investigation was conducted at the same time as the onset of the case, the test found that the carbon monoxide concentration of second floor up to 539 mg/m(3). The on-site testing found that when 2 steam generator in snack room on the first floor turned on, the carbon monoxide concentration on the top of elevator on the second floor was 1225.0 mg/m(3). After the accident, the restaurant replaced a steam generator, the carbon monoxide concentration on the top of the new and old steam generator were 350 mg/m(3) and >1 000 mg/m(3), respectively. After the steam generators were fitted with exhaust smoke pipe and exhasust hood, the carbon monoxide concentrations of on the top of the vegetable transfer elevator and the room on the second floor were both 0.4 mg/m(3), and there were no cases of recurrence. It was determined that this was a carbon monoxide poisoning incident caused by a high concentration of carbon monoxide emitted by the steam generators, which spread to the second floor of the private room through the vegetable transfer elevator.
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Intoxicação por Monóxido de Carbono , Acidentes , Intoxicação por Monóxido de Carbono/epidemiologia , Intoxicação por Monóxido de Carbono/etiologia , Cefaleia , Humanos , FumaçaRESUMO
This corrects the article DOI: 10.1103/PhysRevLett.127.021101.
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We report the properties of sodium (Na) and aluminum (Al) cosmic rays in the rigidity range 2.15 GV to 3.0 TV based on 0.46 million sodium and 0.51 million aluminum nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. We found that Na and Al, together with nitrogen (N), belong to a distinct cosmic ray group. In this group, we observe that, similar to the N flux, both the Na flux and Al flux are well described by the sums of a primary cosmic ray component (proportional to the silicon flux) and a secondary cosmic ray component (proportional to the fluorine flux). The fraction of the primary component increases with rigidity for the N, Na, and Al fluxes and becomes dominant at the highest rigidities. The Na/Si and Al/Si abundance ratios at the source, 0.036±0.003 for Na/Si and 0.103±0.004 for Al/Si, are determined independent of cosmic ray propagation.
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Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Long non-coding RNA OR3A4 facilitates cell proliferation and migration in colorectal cancer through the Wnt/ß-catenin signaling pathway, by W. Sun, G.-R. Chen, J. Wang, X.-Y. Yu, X.-F. Hao, M.-Y. Hu, published in Eur Rev Med Pharmacol Sci 2020; 24 (10): 5360-5366-DOI: 10.26355/eurrev_202005_21319-PMID: 32495870" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/21319.
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Precise knowledge of the charge and rigidity dependence of the secondary cosmic ray fluxes and the secondary-to-primary flux ratios is essential in the understanding of cosmic ray propagation. We report the properties of heavy secondary cosmic ray fluorine F in the rigidity R range 2.15 GV to 2.9 TV based on 0.29 million events collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The fluorine spectrum deviates from a single power law above 200 GV. The heavier secondary-to-primary F/Si flux ratio rigidity dependence is distinctly different from the lighter B/O (or B/C) rigidity dependence. In particular, above 10 GV, the F/Si/B/O ratio can be described by a power law R^{δ} with δ=0.052±0.007. This shows that the propagation properties of heavy cosmic rays, from F to Si, are different from those of light cosmic rays, from He to O, and that the secondary cosmic rays have two classes.
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We report the observation of new properties of primary iron (Fe) cosmic rays in the rigidity range 2.65 GV to 3.0 TV with 0.62×10^{6} iron nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. Above 80.5 GV the rigidity dependence of the cosmic ray Fe flux is identical to the rigidity dependence of the primary cosmic ray He, C, and O fluxes, with the Fe/O flux ratio being constant at 0.155±0.006. This shows that unexpectedly Fe and He, C, and O belong to the same class of primary cosmic rays which is different from the primary cosmic rays Ne, Mg, and Si class.
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We present the precision measurement of the daily proton fluxes in cosmic rays from May 20, 2011 to October 29, 2019 (a total of 2824 days or 114 Bartels rotations) in the rigidity interval from 1 to 100 GV based on 5.5×10^{9} protons collected with the Alpha Magnetic Spectrometer aboard the International Space Station. The proton fluxes exhibit variations on multiple timescales. From 2014 to 2018, we observed recurrent flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. The rigidity dependence of the 27-day periodicity is different from the rigidity dependences of 9-day and 13.5-day periods. Unexpectedly, the strength of 9-day and 13.5-day periodicities increases with increasing rigidities up to â¼10 GV and â¼20 GV, respectively. Then the strength of the periodicities decreases with increasing rigidity up to 100 GV.
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OBJECTIVE: To investigate the expression and function of LINC00463 in pancreatic cancer (PC), and to demonstrate the relationship between LINC00473 expression and clinical pathological characteristics and prognosis of PC. PATIENTS AND METHODS: Expressions of LINC00473 in PC tissues and cell lines were detected using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). LINC00473 siRNA was synthesized to knock down the LINC00473 expression in PANC-1 cells. Proliferation, invasion, and migration abilities of experimental cells were analyzed using cell counting kit-8 (CCK-8) assay and transwell assay, respectively. cAMP activity was detected and protein expression of ß-catenin was measured to explain the underlying mechanism of LINC00473 in PC. The prognosis and clinical pathological features of PC patients were illustrated. RESULTS: LINC00473 was highly expressed in PC tissues and cells. Higher level of LINC00473 was relative with larger tumor size, worse tumor node metastasis (TNM) stage, worse tumor differentiation, higher rates of perineural invasion, and lymphatic invasion. Knockdown of LINC00473 significantly inhibited cell growth, invasion, and migration of PANC-1 cells. LINC00473 activated cAMP and then promoted the phosphorylation of ß-catenin to promote the progression of PC. Furthermore, high expression of LINC00473 and ß-catenin remarkedly indicated poor prognosis of PC patients. CONCLUSIONS: LINC00473 was upregulated in PC tissues and cells, indicating a poor prognosis and clinical pathological features of PC. It promoted PC progression via activating the cAMP/ß-catenin axis, which provided a novel target for the prediction for PC diagnosis, biological therapy, and prognosis.
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AMP Cíclico/metabolismo , Neoplasias Pancreáticas/metabolismo , RNA Longo não Codificante/metabolismo , beta Catenina/metabolismo , Idoso , Células Cultivadas , Feminino , Humanos , Masculino , Neoplasias Pancreáticas/diagnóstico , Prognóstico , RNA Longo não Codificante/genéticaRESUMO
OBJECTIVE: Colorectal cancer (CRC) remains one of the most ordinary cancers worldwide. Recently, researches have suggested the important role of long noncoding RNAs (lncRNAs) in the progression of tumorigenesis. This study aims to identify how lncRNA OR3A4 functions in the development of CRC. PATIENTS AND METHODS: OR3A4 expressions in 54 paired CRC tissues and CRC cell lines were detected by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR). Moreover, the in vitro functions of OR3A4 in CRC cells were identified by performing proliferation assay, wound healing assay, and transwell assay. Besides, the underlying mechanism of OR3A4 in CRC development was explored through Western blot and RT-qPCR. RESULTS: OR3A4 expression was significantly higher in CRC tissues than adjacent normal ones. Cell proliferation, migration, and CRC were inhibited after OR3A4 was knocked down in vitro, which were promoted after upregulation of OR3A4. Moreover, OR3A4 could activate the Wnt/ß-catenin pathway, thus influencing phenotypes of CRC cells. CONCLUSIONS: OR3A4 enhances CRC cell proliferation and migration by activating the Wnt/ß-catenin signaling pathway.
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Movimento Celular , Neoplasias Colorretais/metabolismo , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Proliferação de Células , Células Cultivadas , Neoplasias Colorretais/patologia , Humanos , RNA Longo não Codificante/genéticaRESUMO
Objective: To investigate the safety, efficacy and prognosis of antegrade dissection re-entry (ADR) with the assistance of BridgePoint devices in opening coronary chronic total occlusion (CTO). Methods: A total of 87 consecutive patients, who underwent percutaneous coronary intervention using BridgePoint devices from April 2016 to December 2018 in Xijing Hospital, were included in this study. General information of the selected patients, features of CTO lesions and intraoperative parameters were recorded. Short-term outcomes including technical success rate (defined as achieving TIMI 3 blood flow with residual stenosis<30%), surgical success rate (defined as no major adverse cardiovascular events (MACE) occured while hospitalized), complications, and MACE during hospitalization were observed. MACE included death, recurrent myocardial infarction, target vascular reconstruction (TVR) and cardiac tamponade. Patients were followed up by outpatient or telephone visits at 30 days and 6, 12, 24 and 36 months after discharge. Results: Eighty-seven patients, aged (61±10) years with J-CTO scores (2.49±0.52) were included, and 75(86%) were male. Six patients underwent direct ADR with BridgePoint system, and all were successful. Eighty-one patients underwent rescue ADR using BridgePoint devices, and 62 of them were successful. The success rate of ADR with BridgePoint devices was 78.2% (68/87). Nine out of the 19 failed cases succeeded after the application of rescue antegrade/retrograde technique. The technical success rate was 88.5% (77/87). Coronary perforation occurred in 2 cases (2.3%), one case was treated with covered stent and the other case with tamponade was treated with pericardiocentesis. One patient developed periprocedural myocardial infarction, and one patient suffered from sudden death, and one patient had cardiac tamponade. In-hospital MACE occurred in 3 (3.4%) patients. The surgical success rate was 85.1% (74/87).The procedure time was (175±72)minutes and the amount of contrast used was (449±155)ml. During a follow-up of 17(11, 26) months, the incidence of MACE within 30 days was 4.7% (4/86), while 10.5% (9/86) within 6 months, 17.4% (15/86) within 17 months. Conclusion: Opening CTO with the assistance of BridgePoint devices is feasible and safe, with high success rate and satisfactory outcome.
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Oclusão Coronária , Intervenção Coronária Percutânea , Idoso , Doença Crônica , Angiografia Coronária , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: The aim of this study was to investigate the expression characteristics of LINC01857 in gastric cancer (GCa), and to further study whether it could promote GCa development by modulating microRNA-200b. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine LINC01857 expression in 60 pairs of GCa tissues and adjacent tissues. The interplay between LINC01857 level and clinical indexes and the prognosis of GCa patients was analyzed. Meanwhile, qRT-PCR was used to verify the expression level of LINC01857 in GCa cell lines. LINC01857 knockdown model was constructed by lentivirus transfection in GCa cell lines. Subsequently, the effect of LINC01857 on the biological function of GCa cells was analyzed by Cell Counting Kit 8 (CCK8), wound healing, and transwell assays. Furthermore, the in-depth relationship between LINC01857 and microRNA-200b was explored. RESULTS: QRT-PCR results showed that LINC01857 level in GCa tissues was remarkably higher than that of adjacent tissues, and the difference was statistically significant (p<0.05). Compared with patients with a low level of LINC01857, the rate of lymph node and distant metastasis in patients with a high level of LINC01857 was remarkably higher, while the overall survival rate was lower (p<0.05). In vitro experiments showed that LINC01857 knockdown remarkably decreased the invasion, migration, and crawling ability of GCa cells (p<0.05). Subsequent qRT-PCR results demonstrated that the level of microRNA-200b was remarkably upregulated after the silence of LINC01857. In addition, the silence of microRNA-200b could reverse the biological function of GCa cells induced by the knockout of LINC01857. CONCLUSIONS: LINC01857 was highly expressed in GCa, and was associated with lymph node metastasis, distant metastasis, and poor prognosis of patients with GCa. In addition, LINC01857 enhanced the metastatic ability of GCa cells by regulating microRNA-200b.
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MicroRNAs/genética , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/metabolismo , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , Neoplasias Gástricas/patologiaRESUMO
Protein tyrosine phosphatases (PTPs) are crucial regulators for numerous biological processes in nature. The dysfunction and overexpression of many PTP members have been demonstrated to cause fatal human diseases such as cancers, diabetes, obesity, neurodegenerative diseases and autoimmune disorders. In the past decade, considerable efforts have been devoted to the production of PTPs inhibitors by both academia and the pharmaceutical industry. However, there are only limited drug candidates in clinical trials and no commercial drugs have been approved, implying that further efficient discovery of novel chemical entities competent for inhibition of the specific PTP target in vivo remains yet a challenge. In light of the click-chemistry paradigm which advocates the utilization of concise and selective carbon-heteroatom ligation reactions for the modular construction of useful compound libraries, the Cu(I)-catalyzed azidealkyne 1,3-dipolar cycloaddition reaction (CuAAC) has fueled enormous energy into the modern drug discovery. Recently, this ingenious chemical ligation tool has also revealed efficacious and expeditious in establishing large combinatorial libraries for the acquisition of novel PTPs inhibitors with promising pharmacological profiles. We thus offer here a comprehensive review highlighting the development of PTPs inhibitors accelerated by the CuAAC click chemistry.
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Alcinos/química , Azidas/química , Cobre/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/química , Alcinos/farmacologia , Azidas/farmacologia , Química Click , Cobre/farmacologia , Desenho de Fármacos , Descoberta de Drogas , Humanos , Estrutura Molecular , Proteínas Tirosina Fosfatases/metabolismo , Relação Estrutura-AtividadeRESUMO
A single layer of dense Si quantum dots with average size of 4 nm sandwiched in amorphous SiN layers was prepared by laser crystallization of ultrathin amorphous Si film followed by subsequently thermal annealing. The electroluminescent diodes were fabricated by evaporating Al electrodes on back sides of p-Si substrates and the top surface of samples. Room temperature electroluminescence can be detected with applying the negative voltage around 10V on the top gate electrode and the luminescent intensity is increased with increasing the applied voltage. It was found that the integrated luminescent intensity is linearly proportional to the injection current which suggested the intensity depends on the concentrations of injected carriers after Fowler-Nordheim tunneling through amorphous SiN barriers. The influence of the amorphous SiN with different band gap on the device performance was also discussed briefly.
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Eletroquímica/métodos , Luz , Luminescência , Nitrogênio , Silício , Amônia , Cristalização , Lasers , Microscopia Eletrônica , Nanotecnologia , Teoria Quântica , Dióxido de Silício/química , Análise Espectral Raman/métodosRESUMO
Multilocus sequence typing (MLST) data have revealed many insights into the global epidemiology of Staphylococcus aureus but, with notable exceptions such as Japan, the evidence from most Asian countries is currently limited. Here we have applied MLST to 132 hospital-acquired meticillin-resistant Staphylococcus aureus (HA-MRSA) isolates collected in mainland China in 2002. In all, 102 isolates were recovered from a single tertiary hospital in Guangzhou, South China, and the remaining 30 isolates were recovered from six metropolitan tertiary hospitals from geographically diverse districts corresponding to a total area of more than 2 million km2. The data reveal a striking predominance throughout mainland China of a single clonal lineage, ST 239, which accounts for 97% of the 132 isolates. These data support more limited evidence from previous studies suggesting the widespread predominance of ST 239 throughout hospitals in China, a pattern which possibly extends to the whole of continental Asia. Staphylococcal chromosome cassette mec (SCCmec) typing confirmed the homogeneity of the ST 239 isolates, with the vast majority corresponding to the Hungarian clone (ST 239-III).