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1.
Phys Rev Lett ; 132(24): 240801, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949366

RESUMO

Quantum networks promise unprecedented advantages in information processing and open up intriguing new opportunities in fundamental research, where network topology and network nonlocality fundamentally underlie these applications. Hence, the detections of network topology and nonlocality are crucial, which, however, remain an open problem. Here, we conceive and experimentally demonstrate to determine the network topology and network nonlocality hosted by a triangle quantum network comprising three parties, within and beyond Bell theorem, with a general witness operator for the first time. We anticipate that this unique approach may stimulate further studies toward the efficient characterization of large complex quantum networks so as to better harness the advantage of quantum networks for quantum information applications.

2.
Phys Rev Lett ; 132(20): 203801, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829094

RESUMO

Non-Hermitian systems can exhibit unique quantum phases without any Hermitian counterparts. For example, the latest theoretical studies predict a new surprising phenomenon that bulk bands can localize and dissipate prominently at the system boundary, which is dubbed the non-Hermitian edge burst effect. Here we realize a one-dimensional non-Hermitian Su-Schrieffer-Heeger lattice with bulk translation symmetry implemented with a photonic quantum walk. Employing time-resolved single-photon detection to characterize the chiral motion and boundary localization of bulk bands, we determine experimentally that the dynamics underlying the non-Hermitian edge burst effect is due to the interplay of non-Hermitian skin effect and imaginary band gap closing. This new non-Hermitian physical effect deepens our understanding of quantum dynamics in open quantum systems.

3.
J Clin Nurs ; 33(2): 724-739, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37926935

RESUMO

BACKGROUND: Vicarious trauma can significantly affect the physical and mental health of nurses, as well as their ability to provide quality of care. However, the concept of vicarious trauma has received limited attention and remains controversial in the nursing context. OBJECTIVE: The purpose of this study was to clarify and define the concept of vicarious trauma as it pertains to the nursing context. METHODS: The Schwartz and Kim's three-stage hybrid concept analysis method was used to define the concept. In the theoretical phase, PubMed, CINAHL, OVID, Medline, Embase, Web of Science, Scopus, ProQuest, PsycINFO, CNKI database, VIP database and Wanfang database were used using keywords "nurs*"and "vicarious trauma*", resulting in a total of 25 papers. In the fieldwork phase, we conducted participatory observations in three hospitals and semi-structured in-depth interviews with 18 clinical nurses from seven cities. In the analysis phase, the results of the previous two phases were integrated to develop a comprehensive concept of vicarious trauma in nursing. RESULTS: Based on the results of the theoretical and field phases, we propose the concept of vicarious trauma in nursing as follows: vicarious trauma is a psychological trauma impacting nurses' cognitive schema which they may experience in clinical settings or on social media, resulting from deeply empathize with the physical or emotional trauma of patients, family, or colleagues, such as patients' physical injuries or death, family's grieving feelings and colleagues' received threats and attacks. Positively, vicarious trauma can transform into vicarious post-trauma growth through repositioning and connection, nourishing nurses and promoting their personal and professional development. CONCLUSION: The concept of vicarious trauma in nursing is multidimensional and holistic. This study clarifies the concept of vicarious trauma in nursing using the hybrid concept analysis, providing a framework for future research and practice on vicarious trauma in the nursing field. PATIENT OR PUBLIC CONTRIBUTION: Nurses contributed to the conduct of the study by participating in the data collection via interviews.


Assuntos
Fadiga de Compaixão , Humanos , Saúde Mental , Emoções
4.
BMC Nurs ; 23(1): 283, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671469

RESUMO

BACKGROUND: The shortage of nurses threatens the entire healthcare system, and nursing professionalism can improve nurse retention and enhance the quality of care. However, nursing professionalism is dynamic, and the factors influencing its development are not fully understood. METHODS: A qualitative descriptive study was conducted. Using maximum variation and purposive sampling, 14 southern and northern China participants were recruited. Semi-structured interviews were conducted from May 2022 to August 2023 in face-to-face conversations in offices in the workplace or via voice calls. The interviews were transcribed verbatim and analyzed via thematic analysis. RESULTS: Three main themes emerged: (1) nourishment factors: promoting early sprouting; (2) growth factors: the power of self-activation and overcoming challenges; and (3) rootedness factors: stability and upward momentum. Participants described the early acquisition of nursing professionalism as derived from personality traits, family upbringing, and school professional education, promoting the growth of nursing professionalism through self-activation and overcoming challenges, and maintaining the stable and upward development of nursing professionalism through an upward atmosphere and external motivation. CONCLUSION: We revealed the dynamic factors that influence the development of nursing professionalism, including "nourishment factors", "growth factors", and "rootedness factors". Our findings provide a foundation for future development of nursing professionalism cultivation strategies. Nursing administrators can guide the development of nurses' professionalism from many angles according to the stage they are in, and the development of professionalism deserves more attention. In the future, we can no longer consider the development of nursing professionalism solely as the responsibility of individual nurses; the power of families, organizations, and society is indispensable to jointly promoting nursing professionalism among nurses.

5.
Phys Rev Lett ; 131(15): 150203, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897772

RESUMO

Heisenberg-type measurement uncertainty relations (MURs) of two quantum observables are essential for contemporary research in quantum foundations and quantum information science. Going beyond, here we report the first experimental study of MUR of three quantum observables. We establish rigorously MURs for triplets of unbiased qubit observables as combined approximation errors lower bounded by an incompatibility measure, inspired by the proposal of Busch et al. [Phys. Rev. A 89, 012129 (2014)PLRAAN1050-294710.1103/PhysRevA.89.012129]. We develop a convex programming protocol to numerically find the exact value of the incompatibility measure and the optimal measurements. We propose a novel implementation of the optimal joint measurements and present several experimental demonstrations with a single-photon qubit. We stress that our method is universally applicable to the study of many qubit observables. Besides, we theoretically show that MURs for joint measurement can be attained by sequential measurements in two of our explored cases. We anticipate that this work may stimulate broad interests associated with Heisenberg's uncertainty principle in the case of multiple observables, enriching our understanding of quantum mechanics and inspiring innovative applications in quantum information science.

6.
BMC Musculoskelet Disord ; 24(1): 916, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012586

RESUMO

This report introduces a young adult who has been in bed for more than ten years with end-stage hemophilic arthropathy. He didn't have access to factor VIII (FVIII) in the early stage of hemophilia due to the high costs of clotting replacement therapy. As a result, he is experiencing some difficulties, such as joint contracture, muscular atrophy, severe pain, and poor function of cardiopulmonary. He came to visit us for a comprehensive rehabilitation program, and, finally, he achieved the basic goal of self-care in daily life.


Assuntos
Artrite , Hemofilia A , Artropatias , Masculino , Adulto Jovem , Humanos , Hemofilia A/complicações , Hemofilia A/terapia , Modalidades de Fisioterapia , Artropatias/complicações , Artropatias/diagnóstico por imagem
7.
Opt Express ; 30(25): 45288-45300, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522935

RESUMO

Due to the nonlinearity in phase shifting profilometry (PSP) system, the captured images are often distorted with fringe harmonics, resulting in inaccurate phase map and measurement. Considering the fact that the phase error can be significantly reduced by modeling high-order fringe harmonics, this work formulates the phase extraction problem - with different frequency images and high-order fringe harmonic model - as a maximum likelihood estimation (MLE). To optimize it efficiently, we thus propose a combined-frequency phase extraction (CFPE) solution by introducing a latent phase map and incorporating the famous expectation-maximization (EM) framework. As a result, our CFPE method only needs ∼5% execution time of a high-order baseline, whilst keeps the high-order accuracy. Tested on synthetic images as well as practical measurements, our CFPE method demonstrated its performance improvement of efficiency and accuracy. In addition, our detailed implementation with experimental arrangement is also provided for interested researchers.

8.
Phys Rev Lett ; 129(15): 150401, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269952

RESUMO

While Bell nonlocality of a bipartite system is counterintuitive, multipartite nonlocality in our many-body world turns out to be even more so. Recent theoretical study reveals in a theory-agnostic manner that genuine multipartite nonlocal correlations cannot be explained by any causal theory involving fewer-partite nonclassical resources and global shared randomness. Here, we provide a Bell-type inequality as a test for genuine multipartite nonlocality in network by exploiting a matrix representation of the causal structure of a multipartite system. We further present experimental demonstrations that both four-photon GHZ state and generalized four-photon GHZ state significantly violate the inequality, i.e., the observed four-partite correlations resist explanations involving three-way nonlocal resources subject to local operations and common shared randomness, hence confirming that nature is boundless multipartite nonlocal.

9.
Phys Rev Lett ; 128(4): 040402, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35148126

RESUMO

Quantum theory is commonly formulated in complex Hilbert spaces. However, the question of whether complex numbers need to be given a fundamental role in the theory has been debated since its pioneering days. Recently it has been shown that tests in the spirit of a Bell inequality can reveal quantum predictions in entanglement swapping scenarios that cannot be modeled by the natural real-number analog of standard quantum theory. Here, we tailor such tests for implementation in state-of-the-art photonic systems. We experimentally demonstrate quantum correlations in a network of three parties and two independent EPR sources that violate the constraints of real quantum theory by over 4.5 standard deviations, hence disproving real quantum theory as a universal physical theory.

10.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4654-4665, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581073

RESUMO

Compounds derived from natural products present satisfactory efficacy in disease prevention and treatment. The use of chemical substances in plants to promote healthhas increasingly attracted people's attention. Rutin, a typical flavonoid, is mainly found in various vegetables, fruits and Chinese herbal medicines. As a natural antioxidant, it features many pharmacological activities, such as anti-inflammation, anti-virus, anti-tumor, and prevention and treatment of cardiovascular and cerebrovascular diseases. However, the low bioavailability and poor water solubility limit its clinical application. In view of this, its structure is optimized and modified to afford rutin derivatives with good solubility, high bioavailability, stable metabolism and small toxic side effects. So far, a large number of rutin ethers, esters, and complexes have been synthesized and undergone activity testing. This paper reviews the structural modification of rutin in recent years, and the obtained derivatives have excellent properties and significant biological activity.


Assuntos
Anti-Inflamatórios , Rutina , Antioxidantes , Disponibilidade Biológica , Humanos , Solubilidade
11.
Phys Rev Lett ; 122(9): 090404, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932520

RESUMO

We derive a state-dependent error-disturbance trade-off based on a statistical distance in the sequential measurements of a pair of noncommutative observables and experimentally verify the relation with a photonic qubit system. We anticipate that this Letter may further stimulate the study on the quantum uncertainty principle and related applications in quantum measurements.

12.
BMC Nephrol ; 20(1): 240, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269901

RESUMO

BACKGROUND: To evaluate the treatment of sustained low-efficiency hemodialysis (SLED) against patients with multiple organ dysfunction syndrome (MODS) following wasp stings. METHODS: Clinical data of 35 patients with MODS following wasp stings were retrospectively analysed. These patients were divided into three groups according to the treatment strategy used: 1) hemodialysis (HD) group, 2) continuous veno-venous hemofiltration (CVVH)/HD group, and 3) SLED/HD group. The clinical parameters, treatment outcome, and safety findings were compared among the three groups. RESULTS: The recovery rate (76.92% vs 77.78% vs 91.67%, p = 0.621) and mortality rate (15.38% vs 11.11% vs 8.33%, p = 0.999) were similar among the three groups. When compared to the HD group, patients treated with CVVH/HD or SLED/HD required a shorter period of time to enter into polyuria stage [(24.7 ± 4.3) days vs (20.2 ± 4.7) days vs (18.2 ± 3.0) days, F = 9.11, p = 0.0007], and required a shorter time for serum creatinine to return to normal [(45.7 ± 13.4) days vs (33.1 ± 9.4) days vs (31.9 ± 9.8), F = 5.83, p = 0.0069]; while such parameters had no significant differences between SLED/HD group and CVVH/HD group. The adverse events of hypotension and arrhythmia were found in the HD group, while no adverse events were reported in the SLED/HD and CVVH/HD groups. There was no significant difference in the cost of blood purification treatment between the SLED/HD group and HD group. CONCLUSION: The use of SLED, CVVH and HD provided a comparable recovery and survival rates in patients with MODS secondary to wasp stings. Compared to HD, the use of SLED is recommended as a treatment strategy because of the efficacy on recover of renal function, satisfactory safety outcome, as well as the reasonable treatment cost.


Assuntos
Terapia de Substituição Renal Contínua/normas , Mordeduras e Picadas de Insetos/terapia , Insuficiência de Múltiplos Órgãos/terapia , Diálise Renal/normas , Vespas , Adulto , Animais , Terapia de Substituição Renal Contínua/métodos , Feminino , Humanos , Mordeduras e Picadas de Insetos/complicações , Mordeduras e Picadas de Insetos/diagnóstico , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/etiologia , Diálise Renal/métodos , Estudos Retrospectivos , Resultado do Tratamento
13.
Ren Fail ; 41(1): 814-820, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31488010

RESUMO

Objective: To study the efficacy and safety of sustained low-efficiency diafiltration (SLEDf) versus hemodialysis (HD) for patients with wasp stings who developed stage III acute kidney injury (AKI). Methods: We retrospectively analyzed the clinical data of consecutive patients who developed AKI following wasp stings. All eligible patients received renal replacement therapy in combination with hemoperfusion. Thereafter, blood purification therapy and HD were performed with a volumetrically controlled machine and 1.7 m2 surface, Fresenius Polysulfone HD filter and SLEDf was undertaken with a volumetrically controlled machine and 1.3 m2 surface, Fresenius Polysulfone HD filter. Results: Forty patients developed stage III AKI following wasp stings, including 14 patients that received SLEDf and 26 patients underwent HD. Thirteen patients were aged less than 60 years and underwent HD (group I), 27 patients were aged at least 60 years, including 13 patients undergoing HD (group II) and 14 patients receiving SLEDf (group III). Groups I and II completed 150 and 162 sessions of HD, respectively, and group III completed 156 sessions of sustained low-efficiency blood purification therapy, including 50 sessions of SLEDf. The time to return to normal serum creatinine levels was 38.8 ± 2.7 days for group I, 47.2 ± 5.3 days for group II, and 39.2 ± 3.3 days for group III. A statistically significant difference was observed in time to normal serum creatinine levels among the three groups. Conclusion: Elderly wasp victims have more severe illness than younger wasp victims and SLEDf is safe and superior to HD in recovery of renal function of elderly wasp victims.


Assuntos
Injúria Renal Aguda/terapia , Mordeduras e Picadas de Insetos/complicações , Rim/fisiopatologia , Diálise Renal/métodos , Vespas , APACHE , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/fisiopatologia , Idoso , Animais , Creatinina/sangue , Feminino , Humanos , Mordeduras e Picadas de Insetos/diagnóstico , Mordeduras e Picadas de Insetos/imunologia , Rim/imunologia , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Venenos de Vespas/imunologia
14.
Zhongguo Zhong Yao Za Zhi ; 44(5): 927-934, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30989851

RESUMO

The dynamic accumulation rule of active substances in medicinal plants is of great value not only for medicinal material production and application,but also for the genetic mechanism study on the formation of medicinal ingredients,especially vital to guide medicinal material collection as well as experiment material selection and candidate gene screening in the analysis of biosynthesis pathway. This study investigated the accumulation of curcumins and terpenoids,and the biosynthesis of these metabolites,which are the active metabolites in Curcuma longa,a commonly used traditional Chinese medicine. Rhizoma of C. longa from leaf growing period,rhizome swelling period and dry matter accumulating period were used as experimental materials,to analyze the changes of metabolites and biosynthesis in the three periods by comparative transcriptome and metabolomes analysis.The results indicated that terpenoids accumulation and biosynthesis mainly occurred in leaf growing period,while curcumin accumulation and biosynthesis mainly occurred in dry matter accumulating period. Therefore,we suggested that turmeric rhizomes in leaf growth period were suitable for terpenoids biosynthetic pathway characterization,and rhizome in accumulation of dry matter period was suitable for curcuminoid biosynthesis pathway characterization. This study provides references for medicinal materialproduction and application,as well as biopathway analysis of active compounds for C. longa.


Assuntos
Curcuma/química , Curcumina/análise , Rizoma/química , Terpenos/análise , Compostos Fitoquímicos/análise , Plantas Medicinais/química
15.
J Clin Psychopharmacol ; 38(1): 55-59, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29257786

RESUMO

PURPOSE: The purpose of this study was to assess the efficacy and acceptability of cariprazine treatment in acute exacerbation of schizophrenia. METHODS: This review included randomized controlled trials of patients with acute exacerbation of schizophrenia in relation to efficacy and acceptability. The efficacy outcomes were assessed by pooling standardized mean differences (SMDs) calculated from the difference in the reduction in the mean of the Positive and Negative Syndrome Scale (PANSS) total score, PANSS positive and negative scores, and response rate. The primary acceptability outcomes were determined by pooling the risk ratios (RRs) of discontinuation for any reason, the incidence of serious adverse events, and treatment emergent events. FINDINGS: Four randomized controlled trials consisting of 1843 patients met all inclusion and exclusion criteria. Efficacy analysis showed significant positive effects in relation to cariprazine therapy (SMD: -0.37, P < 0.00001 for PANSS total score change; SMD: -0.32, P < 0.00001 for PANSS positive score change; SMD: -0.32, P < 0.0001 for PANSS negative score change; RR, 1.41; 95% confidence interval [CI], 1.19-1.67; P < 0.0001 for response rate). For primary acceptability outcomes, less patients taking cariprazine discontinued treatment for any reason compared with patients receiving placebo (RR, 0.90; 95% CI, 0.78-1.04; P = 0.16). Significantly less patients on cariprazine had serious adverse events during the double-blind treatment period compared with patients taking placebo (RR, 0.55; 95% CI, 0.34-0.89; P = 0.01). Significantly more patients on cariprazine had treatment emergent events compared with those receiving placebo (RR, 1.10; 95% CI, 1.03-1.18; P = 0.006). IMPLICATIONS: Results suggest that cariprazine may be an effective and acceptable treatment for schizophrenia and future research is warranted.


Assuntos
Antipsicóticos/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde , Piperazinas/uso terapêutico , Esquizofrenia/tratamento farmacológico , Doença Aguda , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Esquizofrenia/diagnóstico , Resultado do Tratamento
16.
Sensors (Basel) ; 18(11)2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30424568

RESUMO

For ultra-rapid orbits provided by the Global Navigation Satellite System (GNSS), the key parameters, accuracy and timeliness, must be taken into consideration in real-time and near real-time applications. However, insufficient observations in later epochs appear to generate low accuracy in observed orbits, for which a correlation between the Dilution of Precision (DOP) of the orbit parameters and their accuracy is found. To correct the observed GNSS ultra-rapid orbit, a correction method based on the DOP values is proposed by building the function models between DOP values and the orbit accuracy. With 10-day orbit determination experiments, the results show that the observed ultra-rapid-orbit errors, generated by insufficient observations, can be corrected by 12⁻22% for the last three hours of the observed orbits. Moreover, considering the timeliness constraints in ultra-rapid-orbit determination, a DOP amplification factor is defined to weight the contribution of each tracking station and optimize the station distribution in the orbit determination procedure. Finally, six schemes are designed to verify the method and strategy in determining the ultra-rapid orbit based on one-month observations. The orbit accuracy is found to decrease by 1.27⁻6.34 cm with increasing amplification factor from 5⁻20%. Thus, the observed ultra-orbit correction method proposed is ideal when considering accuracy and timeliness in ultra-rapid orbit determination.

17.
Analyst ; 142(24): 4843-4851, 2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29160869

RESUMO

In this work, we report an ultrasensitive electrochemical biosensor for microRNA-21 (miRNA-21) detection by using a competitive RNA-RNA hybridization configuration. A biotinylated miRNA of the self-same sequence with the target miRNA is mixed with the samples, and allowed competition with the target miRNA for a thiolated RNA probe immobilized onto a tungsten diselenide (WSe2) nanosheet modified electrode. Thereafter the current response is obtained by forming the hybridized biotinylated miRNA with streptavidin-horseradish peroxidase (HRP) conjugates to catalyze the H2O2 + hydroquinone (HQ) system. Benefiting from the high specific surface area of WSe2 nanosheets, the competitive hybridization configuration and the signal amplification of the H2O2 + HQ detection system, the proposed assay exhibits a wide linear range of 0.0001-100 pM towards target miRNA with a detection limit of 0.06 fM (S/N = 3), and shows excellent discrimination ability for base-mismatched miRNA sequences. Therefore, the designed platform has promising prospects for the detection of miRNA in biomedical research and early clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , MicroRNAs/análise , Nanoestruturas , Hibridização de Ácido Nucleico , Peroxidase do Rábano Silvestre , Humanos , Peróxido de Hidrogênio , MicroRNAs/sangue , Tungstênio
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 416-22, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30265465

RESUMO

Coals and gangues are the main surface dump in the coal mining process. Dynamic monitoring of those dumps using remote sensing technique is of great importance for mine environmental protection. In the traditional classification of visible and near-infrared remote sensing, part of the gangues might be misclassified as coal, due to the phenomenon of "different objects with the same spectrum", resulting in the decrease of classification accuracy. Thus, this study firstly acquired visible and near-infrared spectrums of 12 coal samples and 115 gangue samples from Tiefa mining area in China. Most of the gangue samples' spectrums are different from those of the coals, which can be easily distinguished. While, part of the gangues has the similar spectrum with coal which results in misclassification. With an effort to improve image classification accuracy, furthermore, we acquired the thermal infrared spectrum of the misclassified gangue and the coal samples. The results indicate that there are different spectral characteristics in thermal infrared band between coal and gangue samples, which can be identified easily. Therefore, we proposed a method to separate coal from gangue based on the combination of visible, near-infrared and thermal infrared spectrum. In the first palace, the method conducts measurement on the visible and near-infrared spectrums of all samples for the rough classification recurring to the MAO model. Next, the thermal infrared spectrums of the samples, mixed with gangue and coal are acquired, and the Spectral Absorption Ratio(SAR) is utilized as the evaluation index for the second classification. The fused result of classification originates in the two steps above. The method is further verified by using external samples from Tiefa, Yanzhou, Shendong and Jiangcang mining areas in China, whose results have demonstrated that the method has higher accuracy than that of the traditional classification method based on visible and near-infrared spectrum features. The research results indicates that the conjoint analytical method involving multiple spectrums can solve the phenomenon of "different objects with the same spectrum" in a single band, effectively, which will be of great referential significance in the field of terrain classification based on remote sensing technique.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 89-94, 2017 01.
Artigo em Chinês | MEDLINE | ID: mdl-30192486

RESUMO

Due to the needs of industrial development, the different content and uncertain distribution of magnesite mineral lead to great difficulties in o determining its grade, therefore, we propose a combination of near-infrared spectroscopy and the ELM magnesite grade classification model. The model can achieve rapid classification of magnesite grade. Near infrared spectroscopy, considering that different types of H group in magnesite have different absorption degrees to near-infrared spectroscopy, is used to determine the composition and content of magnesite. It is simple, fast, accurate and efficient without destroying the sample. In this paper, we take magnesite 30 group from Yingkou City, Liaoning Province Dashiqiao for the study, collecting their magnesite NIR data samples at 30×973, using principal component analysis (PCA) for data dimensionality reduction process. The main element contribution rate is greater than 99.99% obtained characteristic variables of 10, established quantitative analysis ELM algorithm mathematical model, take 20 groups of samples as the training samples (including 6 super group, 14 groups non), 10 groups of samples for testing samples (including super grade4 groups, 6 groups non), ELM algorithm model hidden layer nodes selection 20. In order to further improve the classification performance, two kinds improved ELM algorithm models are proposed: conduct optimization selection ELM for the traditional ELM input weights and threshold using the circulation patterns and integrate integration-Featured ELM based on Featured ELM. And compare to which use the artificial method, chemical method and BP neural network model approach. The results showed that magnesite grade classification with the near-infrared spectroscopy and ELM model have a distinct advantage regardless of cost or time, and the accuracy rate can reach over 90%, which provides a new way to classify magnesite grade.

20.
Mol Plant Microbe Interact ; 29(6): 458-67, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26975437

RESUMO

In Sinorhizobium meliloti, the nodG gene is located in the nodFEG operon of the symbiotic plasmid. Although strong sequence similarity (53% amino acid identities) between S. meliloti NodG and Escherichia coli FabG was reported in 1992, it has not been determined whether S. meliloti NodG plays a role in fatty acid synthesis. We report that expression of S. meliloti NodG restores the growth of the E. coli fabG temperature-sensitive mutant CL104 under nonpermissive conditions. Using in vitro assays, we demonstrated that NodG is able to catalyze the reduction of the 3-oxoacyl-ACP intermediates in E. coli fatty acid synthetic reaction. Moreover, although deletion of the S. meliloti nodG gene does not cause any growth defects, upon overexpression of nodG from a plasmid, the S. meliloti fabG gene encoding the canonical 3-oxoacyl-ACP reductase (OAR) can be disrupted without any effects on growth or fatty acid composition. This indicates that S. meliloti nodG encodes an OAR and can play a role in fatty acid synthesis when expressed at sufficiently high levels. Thus, a bacterium can simultaneously possess two or more OARs that can play a role in fatty acid synthesis. Our data also showed that, although SmnodG increases alfalfa nodulation efficiency, it is not essential for alfalfa nodulation.


Assuntos
3-Oxoacil-(Proteína Carreadora de Acil) Redutase/metabolismo , Oxirredutases do Álcool/metabolismo , Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Ácidos Graxos/biossíntese , Sinorhizobium meliloti/metabolismo , 3-Oxoacil-(Proteína Carreadora de Acil) Redutase/genética , Oxirredutases do Álcool/genética , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Ácidos Graxos/genética , Regulação Bacteriana da Expressão Gênica , Medicago sativa/microbiologia , Mutação , Nódulos Radiculares de Plantas/microbiologia , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/crescimento & desenvolvimento , Temperatura
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