1,165 research outputs found
Resistance status of the carmine spider mite, Tetranychus cinnabarinus and the twospotted spider mite, Tetranychus urticae to selected acaricides on strawberries.
The carmine spider mite, Tetranychus cinnabarinus (Boisduval) and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round intensive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respective highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region
Preparation and electrocatalytic performance of gasification slag residual carbon particle electrode
Coal chemical industry is one of the economic pillars of China. Coal gasification slag and gasification wastewater are the wastes produced in the process of coal gasification, and the current treatment is too simple and causes great pollution to the environment. In this paper, microemulsion was used as the capture agent for flotation of coal gasification fine slag, and the physicochemical properties of residual charcoal were analysed by means of industrial analyser, FTIR, BET, SEM, XRD, Raman, XPS and other means of characterization, and the electrochemical properties of the residual charcoal were analysed by means of CV, EIS test, and the electrochemical properties and stability of the residual charcoal as a particle electrode in the three-dimensional electrochemical system were examined, and the feasibility of using it as a The feasibility of the residual carbon as a particle electrode was investigated, and the mechanism of ammonia nitrogen removal by the residual carbon particle electrode was proposed to be analysed. The results show that the flotation residual carbon has a high specific surface area, and the pore structure is dominated by mesopores. In addition, some of the carbon in the residual carbon exhibits a certain degree of electrical conductivity due to graphitization, which provides a basis for its electrochemical applications. In addition, the residual carbon particles electrocatalytic system had lower electrical resistance, which was conducive to accelerating the charge transfer rate. The three-dimensional electrocatalytic system of residual carbon particles had 19.82% higher ammonia nitrogen removal rate than the two-dimensional electrocatalytic system under the same conditions of ammonia nitrogen wastewater degradation, and it has certain catalytic ability.In the residual charcoal particle electrode cycling test, the residual charcoal particles were reused for five times, and the removal rate of ammonia nitrogen only decreased by 5.3%, and this result shows that the residual charcoal particle electrode has good stability. In this paper, a novel particle electrode material in a three-dimensional electrocatalytic system is developed, and through systematic characterisation and performance evaluation, it is demonstrated that the residual charcoal particle electrode of gasification slag has great potential in improving the efficiency of wastewater treatment. The development of residual charcoal particle electrode provides a new idea for the resourceful utilisation of gasification slag, and also provides a new method for wastewater degradation treatment technology
Generation of a curved plasma channel from a discharged capillary for intense laser guiding
Straight plasma channels are widely used to guide relativistic intense laser pulses over several Rayleigh lengths for laser wakefield acceleration. Recently, a curved plasma channel with gradually varied curvature was suggested to guide a fresh intense laser pulse and merge it into a straight channel for staged wakefield acceleration [Phys. Rev. Lett. 120, 154801 (2018)]. In this work, we report the generation of such a curved plasma channel from a discharged capillary. Both longitudinal and transverse density distributions of the plasma inside the channel were diagnosed by analyzing the discharging spectroscopy. Effects of the gas-filling mode, back pressure and discharging voltage on the plasma density distribution inside the specially designed capillary are studied. Experiments show that a longitudinally uniform and transversely parabolic plasma channel with a maximum channel depth of 47.5 μm and length of 3 cm can be produced, which is temporally stable enough for laser guiding. Using such a plasma channel, a laser pulse with duration of 30 fs has been successfully guided along the channel with the propagation direction bent by 10.4°
Most Lithium-rich Low-mass Evolved Stars Revealed as Red Clump stars by Asteroseismology and Spectroscopy
Lithium has confused scientists for decades at almost each scale of the
universe. Lithium-rich giants are peculiar stars with lithium abundances over
model prediction. A large fraction of lithium-rich low-mass evolved stars are
traditionally supposed to be red giant branch (RGB) stars. Recent studies,
however, report that red clump (RC) stars are more frequent than RGB. Here, we
present a uniquely large systematic study combining the direct asteroseismic
analysis with the spectroscopy on the lithium-rich stars. The majority of
lithium-rich stars are confirmed to be RCs, whereas RGBs are minor. We reveal
that the distribution of lithium-rich RGBs steeply decline with the increasing
lithium abundance, showing an upper limit around 2.6 dex, whereas the Li
abundances of RCs extend to much higher values. We also find that the
distributions of mass and nitrogen abundance are notably different between RC
and RGB stars. These findings indicate that there is still unknown process that
significantly affects surface chemical composition in low-mass stellar
evolution.Comment: 27 pages, 10 figures, 3 table
Sar1 assembly regulates membrane constriction and ER export
While dynamin pinches vesicles from the plasma membrane, the Sar1 GTPase specializes in cinching ER membrane tubules
An Updated Search of Steady TeV Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array
Using the data taken from Tibet II High Density (HD) Array (1997
February-1999 September) and Tibet-III array (1999 November-2005 November), our
previous northern sky survey for TeV ray point sources has now been
updated by a factor of 2.8 improved statistics. From to
in declination (Dec) range, no new TeV ray point
sources with sufficiently high significance were identified while the
well-known Crab Nebula and Mrk421 remain to be the brightest TeV ray
sources within the field of view of the Tibet air shower array. Based on the
currently available data and at the 90% confidence level (C.L.), the flux upper
limits for different power law index assumption are re-derived, which are
approximately improved by 1.7 times as compared with our previous reported
limits.Comment: This paper has been accepted by hepn
Neuroprotectants attenuate hypobaric hypoxia-induced brain injuries in cynomolgus monkeys
Hypobaric hypoxia (HH) exposure can cause serious brain injury as well as life-threatening cerebral edema in severe cases. Previous studies on the mechanisms of HH-induced brain injury have been conducted primarily using non-primate animal models that are genetically distant to humans, thus hindering the development of disease treatment. Here, we report that cynomolgus monkeys (Macaca fascicularis) exposed to acute HH developed human-like HH syndrome involving severe brain injury and abnormal behavior. Transcriptome profiling of white blood cells and brain tissue from monkeys exposed to increasing altitude revealed the central role of the HIF-1 and other novel signaling pathways, such as the vitamin D receptor (VDR) signaling pathway, in co-regulating HH-induced inflammation processes. We also observed profound transcriptomic alterations in brains after exposure to acute HH, including the activation of angiogenesis and impairment of aerobic respiration and protein folding processes, which likely underlie the pathological effects of HH-induced brain injury. Administration of progesterone (PROG) and steroid neuroprotectant 5α-androst-3β,5,6β-triol (TRIOL) significantly attenuated brain injuries and rescued the transcriptomic changes induced by acute HH. Functional investigation of the affected genes suggested that these two neuroprotectants protect the brain by targeting different pathways, with PROG enhancing erythropoiesis and TRIOL suppressing glutamate-induced excitotoxicity. Thus, this study advances our understanding of the pathology induced by acute HH and provides potential compounds for the development of neuroprotectant drugs for therapeutic treatment
Observation of CR Anisotropy with ARGO-YBJ
The measurement of the anisotropies of cosmic ray arrival direction provides
important informations on the propagation mechanisms and on the identification
of their sources. In this paper we report the observation of anisotropy regions
at different angular scales. In particular, the observation of a possible
anisotropy on scales between 10 and 30
suggests the presence of unknown features of the magnetic fields the charged
cosmic rays propagate through, as well as potential contributions of nearby
sources to the total flux of cosmic rays. Evidence of new weaker few-degree
excesses throughout the sky region R.A. is
reported for the first time.Comment: Talk given at 12th TAUP Conference 2011, 5-9 September 2011, Munich,
German
Screening Level of PAHs in Sediment Core from Lake Hongfeng, Southwest China
Using data from a 25-year retrospective of polycyclic aromatic hydrocarbons (PAHs) in sediment core from Lake Hongfeng, Southwest China, their possible sources and potential toxicologic significance were investigated. The total PAH concentrations (16 priority PAHs as proposed by the United States Environmental Protection Agency) in sediments ranged from 2936.1 to 5282.3 ng/g and gradually increased from the analyzed deeper sediments to surface sediments. PAHs were dominated by low molecular-weight components, especially phenanthrene (PHEN) and fluorene (FLU). However, a significantly increased number of high molecular-weight (HMW) PAHs was found in upper segments. The temporal trends of individual PAH species suggest that there may have been a change in energy use from low- to high-temperature combustion, especially after approximately 2001. PAH input to Lake Hongfeng originated mainly from domestic coal combustion and biomass burning, whereas fuel combustion characteristics have also been found in recent years. Sediment-quality assessment implied that potential adverse biologic impact could be a probability for most low-ring PAHs (including naphthalene, acenaphthylene, acenaphthylene, FLU, PHEN, and anthracene). Nevertheless, more concern should be paid to HMW PAHs in the future due to their rapidly increasing trends in upper sediments. Because only one core was analyzed in this study, more work is needed to confirm the sources and toxicity of PAHs in Lake Hongfeng
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