1,151 research outputs found
Distributed Impulsive Consensus of the Multiagent System without Velocity Measurement
This paper deals with the distributed consensus of the multiagent system. In particular, we consider the case where the velocity (second state) is unmeasurable and the communication among agents occurs at sampling instants. Based on the impulsive control theory, we propose an impulsive consensus algorithm that extends some of our previous work to account for the lack of velocity measurement. By using the stability theory of the impulsive system, some necessary and sufficient conditions are obtained to ensure the consensus of the controlled multiagent system. It is shown that the control gains, the sampled period and the eigenvalues of Laplacian matrix of communication graph play key roles in achieving consensus. Finally, a numerical simulation is provided to illustrate the effectiveness of the proposed algorithm
Detecting unambiguously non-Abelian geometric phases with trapped ions
We propose for the first time an experimentally feasible scheme to disclose
the noncommutative effects induced by a light-induced non-Abelian gauge
structure with trapped ions. Under an appropriate configuration, a true
non-Abelian gauge potential naturally arises in connection with the geometric
phase associated with two degenerated dark states in a four-state atomic system
interacting with three pulsed laser fields. We show that the population in
atomic state at the end of a composed path formed by two closed loops and
in the parameter space can be significantly different from the composed
counter-ordered path. This population difference is directly induced by the
noncommutative feature of non-Abelian geometric phases and can be detected
unambiguously with current technology.Comment: 6 page
Transcriptome Profiling of the Whitefly Bemisia tabaci MED in Response to Single Infection of Tomato yellow leaf curl virus, Tomato chlorosis virus, and Their Co-infection
Tomato yellow leaf curl virus (TYLCV) and Tomato chlorosis virus (ToCV) are two of the most devastating cultivated tomato viruses, causing significant crop losses worldwide. As the vector of both TYLCV and ToCV, the whitefly Bemisia tabaci Mediterranean (MED) is mainly responsible for the rapid spread and mixed infection of TYLCV and ToCV in China. However, little is known concerning B. tabaci MED's molecular response to TYLCV and ToCV infection or their co-infection. We determined the transcriptional responses of the whitefly MED to TYLCV infection, ToCV infection, and TYLCV&ToCV co-infection using Illumina sequencing. In all, 78, 221, and 60 differentially expressed genes (DEGs) were identified in TYLCV-infected, ToCV-infected, and TYLCV&ToCV co-infected whiteflies, respectively, compared with non-viruliferous whiteflies. Differentially regulated genes were sorted according to their roles in detoxification, stress response, immune response, transport, primary metabolism, cell function, and total fitness in whiteflies after feeding on virus-infected tomato plants. Alterations in the transcription profiles of genes involved in transport and energy metabolism occurred between TYLCV&ToCV co-infection and single infection with TYLCV or ToCV; this may be associated with the adaptation of the insect vector upon co-infection of the two viruses. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses demonstrated that the single infection with TYLCV or ToCV and the TYLCV&ToCV co-infection could perturb metabolic processes and metabolic pathways. Taken together, our results provide basis for further exploration of the molecular mechanisms of the response to TYLCV, ToCV single infection, and TYLCV&ToCV co-infection in B. tabaci MED, which will add to our knowledge of the interactions between plant viruses and insect vectors
Efficacy and safety of vitrectomy with internal limiting membrane peeling for diabetic macular edema: a Meta-analysis
AIM: To evaluate the efficacy and safety of vitrectomy with internal limiting membrane (ILM) peeling for diabetic macular edema (DME).
METHODS: The PubMed, Embase, Web of Science, Cochrane, SionMed, ClinicalTrials.gov, CNKI databases and Wanfang databases, published until Oct. 2017, were searched to identify studies comparing the clinical outcomes following vitrectomy with and without ILM peeling, for treating DME. Pooled results were expressed as odds ratios (ORs) with corresponding 95% confidence intervals (CI) for vitrectomy with and without ILM peeling with regard to best corrected visual acuity (BCVA), central macular thickness (CMT), and complication incidents.
RESULTS: A total of 14 studies involving 857 eyes were included of which three studies were Chinese and the rests were English literatures. Meta-analysis indicated that compared with vitrectomy alone, vitrectomy with ILM peeling could improve BCVA more obviously (OR=1.66, 95%CI: 1.12-2.46, P=0.01) and had higher rate of CMT reduction (OR=3.89, 95%CI: 1.37-11.11, P=0.01). There were significant statistical differences between the two surgical methods for both BCVA and CMT (P<0.05). For the incidence of intraoperative and postoperative complications, the incidence of epiretinal membrane (ERM) was slightly lower in the ILM peeling group than the group without ILM peeling (OR=0.38, 95%CI: 0.07-2.00, P=0.25), although insignificant statistically. Other incidences of overall complications, iatrogenic peripheral retinal break and increased intraocular pressure indicated no significant difference between two groups (OR=1.19, 95%CI: 0.82-1.73, P=0.36; OR=1.21, 95%CI: 0.66-2.21, P=0.53; OR=1.34, 95%CI: 0.75-2.40, P=0.32).
CONCLUSION: Vitrectomy is effective for DME and the effect can be improved by additional ILM peeling, especially for anatomical efficacy, without increasing the incidence of intraoperative and postoperative complications. However, it is imperative to gain more evaluation in the future due to the paucity of prospective randomized study
Spherical Indicatrices of a Bertrand Curve in Three Lie Groups
In this paper, new representations of a Bertrand curve pair in three
dimensional Lie groups with bi-invariant metric are given. Besides, the
spherical indicatrices of a Bertrand curve pair are obtain and the relations
between the spherical indicatrices and new representations of Bertrand curve
pair are shown.Comment: 12 page
Dorsalis Pedis Artery Blood Pressure is a Good indicator for Blood Pressure Monitoring during Shock and Recovery
Abstract To compare Supine ankle dorsalis pedis artery and brachial artery blood pressure in patients during shock resuscitation and of different ages was compared, in order to evaluate the clinical value of ankle dorsalis pedis artery blood press monitoring. 80 hypovolemic shock (trauma, hemorrhagic shock) patients and 150 selected patients, including 50 children, 50 young and 50 old patients, were enrolled in this study. The left dorsalis pedis artery and brachial blood pressure were monitored by multi-function monitor in all patients. We observed a correlation between dorsalis pedis artery blood pressure and brachial blood pressure during the period of shock and the recovery with the use of vasoactive drugs. In addition, the values of dorsalis pedis artery blood pressure and brachial blood pressure were significantly correlated in three groups with different ages. There is a positive correlation between dorsalis pedis artery blood pressure and brachial blood pressure in the state of shock and recovery as well as in populations of different ages. Monitoring dorsalis pedis artery blood pressure can reflect the hemodynamic changes timely and accurately, and has important clinical value
KFe_2Se_2 is the parent compound of K-doped iron selenide superconductors
We elucidate the existing controversies in the newly discovered K-doped iron
selenide (KxFe2-ySe2-z) superconductors. The stoichiometric KFe2Se2 with
\surd2\times\surd2 charge ordering was identified as the parent compound of
KxFe2-ySe2-z superconductor using scanning tunneling microscopy and
spectroscopy. The superconductivity is induced in KFe2Se2 by either Se
vacancies or interacting with the anti-ferromagnetic K2Fe4Se5 compound. Totally
four phases were found to exist in KxFe2-ySe2-z: parent compound KFe2Se2,
superconducting KFe2Se2 with \surd2\times\surd5 charge ordering,
superconducting KFe2Se2-z with Se vacancies and insulating K2Fe4Se5 with
\surd5\times\surd5 Fe vacancy order. The phase separation takes place at the
mesoscopic scale under standard molecular beam epitaxy condition
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