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Organic polyradicals with a high-spin ground state and quantum magnetic properties suitable for spin manipulation are valuable materials for diverse innovative technologies, including quantum devices. However, the typically high reactivity and low stability of conventional polyradicals present a major obstacle to such applications. In this study, a highly stable carbon-centered triradical TR with a quartet ground state and excellent stability (τ1/2 of â¼90 days in air-saturated toluene at room temperature) is achieved, which shows apposite magnetic anisotropy and Zeeman splitting partition with favorable addressability. By virtue of the optimal stability, thorough structural and magnetic characterizations are realized. With X-ray crystallography unambiguously proving the molecular structure, the quartet ground state (ΔED-Q = 0.78 kcal/mol) is confirmed by the SQUID measurements, while the cw- and pulsed EPR techniques offer additional supportive evidence for the high-spin nature. Remarkably, owing to the easily attained magnetic anisotropy, selective excitations between different Zeeman splitting levels are successfully demonstrated with TR in its frozen toluene solution without the requirement for special alignment, which is unprecedented for organic polyradicals. Along with the millisecond spin-lattice relaxation and microsecond coherence time manifested by TR, this triradical is promising for potential coherent spin manipulation applications as a multienergy-level quantum information carrier.
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Selenium (Se) is an essential trace element for humans. Low concentrations of Se can promote plant growth and development. Enhancing grain yield and crop Se content is significant, as major food crops generally have low Se content. Studies have shown that Se biofortification can significantly increase Se content in plant tissues. In this study, the genetic transformation of wheat was conducted to evaluate the agronomic traits of non-transgenic control and transgenic wheat before and after Se application. Se content, speciation, and transfer coefficients in wheat grains were detected. Molecular docking simulations and transcriptome data were utilized to explore the effects of selenium-binding protein-A TaSBP-A on wheat growth and grain Se accumulation and transport. The results showed that TaSBP-A gene overexpression significantly increased plant height (by 18.50%), number of spikelets (by 11.74%), and number of grains in a spike (by 35.66%) in wheat. Under normal growth conditions, Se content in transgenic wheat grains did not change significantly, but after applying sodium selenite, Se content in transgenic wheat grains significantly increased. Analysis of Se speciation revealed that organic forms of selenomethionine (SeMet) and selenocysteine (SeCys) predominated in both W48 and transgenic wheat grains. Moreover, TaSBP-A significantly increased the transfer coefficients of Se from solution to roots and from flag leaves to grains. Additionally, it was found that with the increase in TaSBP-A gene overexpression levels in transgenic wheat, the transfer coefficient of Se from flag leaves to grains also increased.
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Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Proteínas de Unión al Selenio , Selenio , Selenito de Sodio , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/crecimiento & desarrollo , Proteínas de Unión al Selenio/metabolismo , Proteínas de Unión al Selenio/genética , Selenio/metabolismo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Selenito de Sodio/metabolismo , Grano Comestible/metabolismo , Grano Comestible/genética , Grano Comestible/crecimiento & desarrollo , Simulación del Acoplamiento Molecular , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Semillas/genética , Semillas/efectos de los fármacosRESUMEN
Stable carbon-based polyradicals exhibiting strong spin-spin coupling and slow depolarization processes are particularly attractive functional materials. A new molecular motif synthesized by a convenient method that allows the integration of stable, high-spin radicals to (hetero)aromatic polycycles has been developed, as illustrated by a non-Kekulé diradical showing a triplet ground state with long persistency (τ1/2 ≈31â h) in air. Compared to the widely used 1,3-phenylene, the newly designed (diaza)pyrene-4,10-diyl moiety is for the first time demonstrated to confer ferromagnetic (FM) spin coupling, allowing delocalized non-disjoint SOMOs. With the X-ray crystallography unambiguously proving the diradical structure, the triplet ground state was thoroughly characterized. A large ΔES-T of 1.1â kcal/mol, proving the strong FM coupling effect, was revealed consistently by superconducting quantum interference device (SQUID) measurements and variable-temperature electron paramagnetic resonance (EPR) spectroscopy, while the zero-field splitting and triplet nutation characters were examined by continuous-wave and pulsed EPR spectroscopy. A millisecond spin-lattice relaxation time was also detected. The current study not only offers a new molecular motif enabling FM coupling between carbon-based spins, but more importantly presents a general method for installing stable polyradicals into functional π-systems.
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Objective@#To understand the prevalence and pattern of abnormal uterine bleeding (AUB) among female medical college students in Shanghai,to provide a basis for menstrual health intervention for female college students.@*Methods@#A total of 912 female medical students from a university in Shanghai were selected through cluster sampling. An anonymous questionnaire survey on menstrual history and related factors was conducted in March 2021.@*Results@#The prevalence of AUB among female medical college students was 39.9%, with cycle disordered and non cycle disordered AUB of 24.7% and 15.2%, respectively. Among female college students with AUB, 21.7% had two or three abnormal menstrual symptoms. Multivariate Logistic analysis showed that sleep quality was associated with both types of AUB, and female undergraduates with poorer and poor sleep quality were at increased risk of both cyclic disordered AUB ( OR =2.05) and non cyclic disordered AUB ( OR =2.00). Low BMI ( OR =1.66) and weight gain and loss ( OR =1.76) were associated with cycle disordered AUB. Frequent insomnia ( OR =2.45) was associated with non cyclic disordered AUB( P <0.05).@*Conclusion@#Abnormal uterine bleeding (AUB) is common in female college students, female medical college students with AUB have multiple concurrent abnormal bleeding patterns. Factors associated with AUB varied according to the type of AUB, with sleep quality correlates with both types of AUB.
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Isolated large-spin Heisenberg antiferromagnetic uniform chain is quite rare. Here, we have successfully synthesized an ideal one-dimensional (1D) S = 5/2 linear-chain antiferromagnet [C2NH8]3[Fe(SO4)3], which crystallizes in a trigonal lattice with the space group R3c. A broad maximum at Tmax = 18 K is observed in the magnetic susceptibility curve. Notably, no long-range magnetic ordering is observed down to 2 K even if the material has a large Curie-Weiss temperature of θCW = -25.5 K. High-field magnetization at 2 K shows a linear increase until saturation at 30 T, and a high-field electron spin resonance (ESR) reveals the absence of a zero-field spin gap. The intrachain interaction J and interchain interaction J' are determined. Quite a small ratio of J'/J < 2.5 × 10-3 suggests that [C2NH8]3[Fe(SO4)3] behaves as an ideal 1D uniform linear-chain antiferromagnet, in which the magnetic ordering is prevented by the extremely small interchain interaction and quantum fluctuation even for a classical spin of S = 5/2.
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Utilize the prevalence, associated factors and population distribution of AD and MCI among residents of the Hubei province aged 60 years or over to prove that elderly people who study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle, will prevent or slow the decline in cognitive ability. If elderly people study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle, can prevent or slow the decline in cognitive ability. A cross-sectional study was used for the recruitment of subjects. The screened patients with AD and MCI were then selected as patients in a case−control study. A total of 4314 subjects were recruited into the study. The prevalence of AD and MCI was 1.44% and 10.04%, respectively. The prevalence of AD and MCI differed significantly as a function of age and gender (p < 0.05). The preventative factors for AD and MCI, separately, included a happy marriage (OR = 0.69, 95%CI: 0.36−1.35) and higher education (OR = 0.65, 95%CI: 0.55−0.78). The risk factors for AD and MCI, separately, included infrequent participation in social activities (OR = 1.00, 95%CI: 0.60−1.66) and infrequent communication with children (OR = 1.35, 95%CI: 1.09−1.69). The prevalence of AD for people aged 60 or over in the Hubei province was lower than the national average of 3.06%. The prevalence of MCI was within the national range (5.2−23.4%). The influencing factors of AD and MCI were associated with the participants' social connections, lifestyle behaviors, somatic diseases and so on. The elderly people who study and communicate with others, take part in regular physical exercise and choose a healthy lifestyle will prevent or slow the decline in cognitive ability. The conclusion section has been replaced.
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Water reorientation is essential in a wide range of chemical and biological processes. However, the effects of such reorientation through rotation around the metal-oxygen bond on the chemical and physical properties of the resulting complex are usually ignored. Most studies focus on the donor property of water as a recognized σ donor-type ligand rather than a participant in the π interaction. Although a theoretical approach to study water-rotation effects on the functionality of a complex has recently been conducted, it has not been experimentally demonstrated. In this study, we determine that the magnetic anisotropy of a Co(II) complex can be effectively controlled by the slight rotation of coordinating water ligands, which is achieved by a two-step structural phase transition. When the water molecule is rotated by 21.2 ± 0.2° around the Co-O bond, the directional magnetic susceptibility of the single crystal changes by approximately 30% along the a-axis due to the rotation of the magnetic anisotropy axis through the modification of the π interaction between cobalt(II) and the water ligand. The theoretical calculations further support the hypothesis that the reorientation of water molecules is a key factor contributing to the magnetic anisotropy transition of this complex.
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In order to investigate the prevalence, O serogroup, virulence genes and antibiotic resistance of Shiga toxin-producing Escherichia coli (STEC) in two beef plants in China, a total of 600 samples collected from 6 sites (feces, hide, pre-evisceration carcasses, post-washing carcasses, chilled carcasses and meat, 50 samples per site in each plant) were screened for the existence of Shiga toxin-encoding genes by PCR. STEC strains in positives were isolated and characterized for serogroup and antibiotic sensitivity. The PCR prevalence rate in each site was 45.0%, 31.0%, 14.0%, 13.0%, 9.0% and 18.0%, respectively. Sixteen O serogroups including O157, O146 and O76 which are associated with disease were identified. The existence of both stx1 and stx2 genes was the most common among the isolated strains (42.3%). Among the overall 26 isolates, seven and three were resistant to at least three and ten antibiotics, indicating a high antibiotic resistance in STEC strains isolated from the study.
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Mataderos , Carne Roja/microbiología , Escherichia coli Shiga-Toxigénica/genética , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Animales , Pueblo Asiatico , Bovinos/microbiología , Farmacorresistencia Bacteriana/genética , Heces/microbiología , Humanos , Industria para Empaquetado de Carne , Serogrupo , Escherichia coli Shiga-Toxigénica/clasificación , Virulencia/genéticaRESUMEN
Three mononuclear octahedral Co(II) complexes are reported, [Co(py)4(SCN)2] (1), [Co(py)4(Cl)2]·H2O (2), and [Co(py)4(Br)2] (3), that exhibit different distortions with compression (1) or elongation (2 and 3) of the axial positions. Easy plane magnetic anisotropy was confirmed by magnetic, HF-EPR, and computational studies for all complexes. Further analyses indicate that both the sign and magnitude of zero-field splitting parameters experience a significant change (D ≥ ±150 cm-1) by tuning of the axial and equatorial ligand field strength. Slow magnetic relaxation is observed for all compounds which is dominated by the Raman process involving both acoustic and optical phonons.
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OBJECTIVE: To determine a method to reduce specimen hemolysis rates in pediatric blood specimens. METHODS: A total of 290 blood specimens from pediatric patients were classiï¬ed into the capped group or uncapped group. The hemolysis index and levels of lactate dehydrogenase (LDH) were measured using an automated biochemical analyzer. Also, we performed a paired test to measure the concentration of free hemoglobin in specimens from 25 randomly selected healthy adult volunteers, using a direct spectrophotometric technique. RESULTS: The hemolytic rate of capped specimens was 2-fold higher than that of uncapped specimens. We found significant differences for LDH. Also, there was a significant difference in the concentration of free hemoglobin in the random-volunteers test. CONCLUSIONS: Eliminating the residual negative pressure of vacuum blood-collection tubes was effective at reducing the macrohemolysis and/or microhemolysis rate.
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Recolección de Muestras de Sangre/normas , Hemólisis , Adolescente , Adulto , Recolección de Muestras de Sangre/efectos adversos , Recolección de Muestras de Sangre/instrumentación , Recolección de Muestras de Sangre/métodos , Niño , Femenino , Hemoglobinas/análisis , Humanos , L-Lactato Deshidrogenasa/sangre , Masculino , VacioRESUMEN
Purpose Following the analytical phase, the current practice of many hospital laboratories involves the manual verification of all test results followed by the production of the report. However, manual verification is a time-consuming and tedious process. In this paper, we provide a detailed description of how to design autoverification rules for thyroid function test profiles and sex hormones. Materials and methods We used DM2 (Data manager 2) to construct the algorithm and build the database for autoverification of thyroid function test profiles and sex hormones, with reference to Boolean logic, Auto 10-A and CLSI'88. The rules consist of checking quality control, instrument error flags, critical values, the analytical measurement range (AMR), the limit range, consistency check and delta check. Firstly, we established the rules in the DM2, collected clinical specimens for validation, then tested the rules in a 'live' environment. Results Agreement was achieved between manual verification by two senior laboratory personnel and verification using the autoverification rules in 99.78% of the cases. The total autoverification rate for all tests was 77.06%. Following implementation of the rules, the laboratory turnaround time (TAT) was reduced by 54.55% and staffing numbers fell from three to two whole time equivalents (WTE). Statistical analysis resulted in a kappa statistic of 0.99 ( P < 0.001). Moreover, after implementing the autoverification rules, the error rate fell to 0.04%, indicating that errors were almost completely eliminated. Conclusion Implementing autoverification rules can reduce TAT, minimize the number of samples that require manual verification and allow for a reduction in staffing numbers. It also allows laboratory staff to devote more time and effort to the handling of problematic test results and contributing to improved patient care.
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Técnicas de Diagnóstico Endocrino/normas , Hormonas Esteroides Gonadales/sangre , Laboratorios de Hospital/organización & administración , Laboratorios de Hospital/normas , Validación de Programas de Computación , Pruebas de Función de la Tiroides/normas , Algoritmos , Humanos , Control de Calidad , Valores de ReferenciaRESUMEN
BACKGROUND: We planned a study to establish whether spurious hemolysis may occur when negative pressure remains in vacuum tubes. METHODS: Four tubes with different vacuum levels (-54, -65, -74, and -86 kPa) were used to examine blood drawn from one healthy volunteer; the tubes were allowed to stand for different times (1, 2, 3, and 4 hours). The plasma was separated and immediately tested for free hemoglobin (FHb). Thirty patients were enrolled in a verification experiment. RESULTS: The degree of hemolysis observed was greater when the remaining negative pressure was higher. Significant differences were recorded in the verification experiment. CONCLUSIONS: The results suggest that residual negative pressure might increase the risk of spurious hemolysis.
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Pruebas Hematológicas , Hemólisis , Vacio , Recuento de Células Sanguíneas , Hemoglobinas , HumanosRESUMEN
Autoverification is a process of using computer-based rules to verify clinical laboratory test results without manual review. But to date, there are few published articles on the use of autoverification over the course of years in a clinical laboratory. In our study, we firstly described the development and implementation of autoverification rules for enzyme-linked immunosorbent assay (ELISA) results of hepatitis B virus (HBV) serological markers in a clinical immunology laboratory. We designed the autoverification rules for HBV by using Boolean logic on five clinically used serological markers in accordance with the framework of AUTO-10A, issued by the American Clinical Laboratory Standards Institute in 2006. The rules were written into the laboratory information system (LIS) and installed in the computer, so we could use the LIS to screen the test results. If the results passed the autoverification rules, they could be sent to doctors immediately. To evaluate the autoverification rules, we applied the real-time data of 11,585 patients with the autoverification rules. The autoverification rate of the five HBV serological markers was 79.5%. Furthermore, the turnaround time (TAT) was reduced by 38% (78 minutes vs. 126 minutes). The error rate was nearly eliminated. These results show that using LIS with autoverification rules can shorten TAT, enhance efficiency, and reduce manual review errors.