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Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) is an important natural enemy of many species of lepidopterous pests. The effects of heat stress temperature (33, 36, and 39 °C), duration of exposure (2, 4, 6, and 8 h), and developmental stage during exposure (embryo-first instar larvae, second instar larvae, prepupae, and pupae) on the development and reproduction of parasitoid T. bactrae were investigated in the laboratory. When exposed to 39 °C for 8 h during pupal stage, only 19.90% adults emerged from host eggs, and more than 14% were deformed (wings were folded or incomplete). Parasitoid females exposed to 39 °C for 8 h as prepupae only lived for 1.45 days and parasitized about 23.5 host eggs. Moreover, life-table parameters of T. bactrae were also influenced by exposure to heat stress temperatures during each preimaginal developmental stage. Based on these results, we propose that T. bactrae is susceptible to high temperatures, especially at 39 °C. Thus, this parasitoid may be more effectively controlling lepidopterous pests during cooler weather conditions.
The 3D morphological evolution of titanium foams as they undergo a two-step fabrication process is quantitatively characterized through x-ray micro- and nano-tomography. In the first process step, a Cu–Ti–Cr–Zr prealloy is immersed in liquid Mg, where Cu is alloyed with Mg while a skeleton of crystalline Ti–Cr–Zr is created. In the second step, the Mg–Cu phase is etched in acid, leaving a Ti–Cr–Zr foam with submicron struts. 3D images of these solidified Ti–Cr–Zr/Mg–Cu composites and leached Ti–Cr–Zr foams are acquired after 5, 10, and 30 min exposure to liquid Mg. As the Mg exposure time increases, the Ti–Cr–Zr ligaments grow in size. The tortuosity loosely follows the Bruggeman relation. The interfacial surface distribution of these Ti-foams is qualitatively similar to other nano-porous metal prepared by one-step dealloying. The characteristic length of the Mg–Cu phase and pores are also reported.
Contrary to concerns that fructose may have adverse metabolic effects, there is evidence that small, ‘catalytic’ doses ( ≤ 10 g/meal) of fructose decrease the glycaemic response to high-glycaemic index meals in human subjects. To assess the longer-term effects of ‘catalytic’ doses of fructose, we undertook a meta-analysis of controlled feeding trials. We searched MEDLINE, EMBASE, CINAHL and the Cochrane Library. Analyses included all controlled feeding trials ≥ 7 d featuring ‘catalytic’ fructose doses ( ≤ 36 g/d) in isoenergetic exchange for other carbohydrates. Data were pooled by the generic inverse variance method using random-effects models and expressed as mean differences (MD) with 95 % CI. Heterogeneity was assessed by the Q statistic and quantified by I2. The Heyland Methodological Quality Score assessed study quality. A total of six feeding trials (n 118) met the eligibility criteria. ‘Catalytic’ doses of fructose significantly reduced HbA1c (MD − 0·40, 95 % CI − 0·72, − 0·08) and fasting glucose (MD − 0·25, 95 % CI − 0·44, − 0·07). This benefit was seen in the absence of adverse effects on fasting insulin, body weight, TAG or uric acid. Subgroup and sensitivity analyses showed evidence of effect modification under certain conditions. The small number of trials and their relatively short duration limit the strength of the conclusions. In conclusion, this small meta-analysis shows that ‘catalytic’ fructose doses ( ≤ 36 g/d) may improve glycaemic control without adverse effects on body weight, TAG, insulin and uric acid. There is a need for larger, longer ( ≥ 6 months) trials using ‘catalytic’ fructose to confirm these results.
The Orai1-STIM1 constructed store-operated Ca2+ channels (SOCs) have been found to exert several essential Ca2+ entry/signaling cascades, e.g., the generation of immune response in T lymphocytes. Although biochemical and novel imaging evidence appear to indicate that Orai1 and STIM1 interact with each other to achieve store-operated Ca2+ entry (SOCE), the detailed mechanism of functional SOCE in situ has yet to be fully understood. In this study, green fluorescence protein (EGFP as donor) targeted to either the N- or C-terminal of Orai1 (wild type or ▵1-90+▵267-301 double deletion type) and mOrange (as acceptor) tagged STIM1 were used to comprise a fluorescence resonance energy transfer (FRET) pair within living PC12 cells. The fluorescence lifetime map and histogram/distribution of each single cell, determined by one-photon excitation fluorescence lifetime imaging microscopy (FLIM), was used to visualize FRET and show the Orai1 homodimer and Orai1-STIM1 binding. Both the color-coded lifetime map and the distribution of EGFP-tagged Orai1 significantly changed after the administration of thapsigargin, the SOCE stimulating agent. The FRET efficiency from each experimental set was also calculated and compared using double exponential analysis. In summary, we show the detailed interactions Orai1-Orai1 and Orai1-STIM1 within intact living cells by using the FLIM-FRET technique.
Experiments using a biased multiblock limiter in the KT-5C tokamak show that positive biasing is more effective than negative biasing in modifying the edge electric field, suppressing fluctuations and improving plasma confinement. The biasing effect varies with the limiter area, the toroidal magnetic field and the biasing voltage. By positive biasing, the edge profiles of the plasma potential, the electron temperature and the density become steeper, resulting in a reduced edge particle flux, an increased global particle confinement time and lower fluctuation levels of the edge plasma.
An equation is derived for the growth rates of the beam-plasma instability excited by non-thermal electrons with arbitrary distribution function, and it is shown that the reactive instability does not depend on the assumption of a monoenergetic distribution. Hence the properties of electromagnetic waves are calculated for the hollow beam and loss-cone distribution. Hence the properties of electromagnetic waves are calculated for the hollow beam and loss-cone distribution functions. The general characteristics and structures of the growth rates are similar to the results for the monoenergetic distribution, but there are still some differences in the relation between the growth rates and the relevant parameters, such as the ambient parameter ωpe/Ωe, the angle of propagation θ and the pitch angle a. The main purpose of this paper is to compare the properties of the beam-plasma instability (reactive) and the electron-cyclotron maser instability (kinetic) under similar ambient conditions. The calculations show that both kinds of instabilities are easily excited at larger angles of propagation with respect to the ambient magnetic field, which means that both depend mainly on the free energy of the non-thermal electrons perpendicular to the magnetic field. The magnitudes of the growth rates of the two kinds of instabilities are comparable under the same ambient conditions. However, because the non-resonant wave—particle interaction is taken into consideration for the beam-plasma instability, which makes the resonant peaks broaden and connect with each other, the spectra of the beam-plasma instability are also more complicated than that of the maser instability, and the range of the angle of propagation of the growing waves in the non-resonant case is also larger than that in the resonant case.
In the impulsive phase of solar flares, the electrostatic waves can be excited during magnetic reconnection. The proton and electron at reconnecting X points can be accelerated by perpendicular propagating electrostatic waves.
The effects of the propagation angle of electromagnetic waves and
angle of non-thermal electrons on the electron cyclotron maser instability
beam–plasma instability are compared. It is pointed out if the direction
propagation of electromagnetic waves is opposite to the direction of the
electrons, the maser instability will be suppressed, and hence it cannot
the radiation with narrow bandwidth excited by energetic electrons propagating
downwards in solar flares, such as millisecond spikes, blips and the type
bursts with positive-frequency drift. This discrepancy may be solved by
non-resonant wave–particle interaction in the beam–plasma instability,
which the electromagnetic waves propagating in the same direction as the
injected electron beam are mainly composed of the ordinary modes (left-circular
polarization), while the electromagnetic waves propagating in the
opposite direction to the beam are mainly composed of the extraordinary
(right-circular polarization). This result is compared with a typical model
magnetic tube in solar flares, in which the non-thermal electrons propagating
upwards excite spikes, blips and type III bursts in the metre and decimetre
bands, while the electron beams propagating downwards excite these temporal
and spectral structures in the microwave bands.
It is proved that a system of three-wave coupling with weak damping
same sign of the coupling coefficients can be completely described by the
Weierstrass function. On the basis of the bifurcation theory of the Weierstrass
function that we have developed, criteria are found for distinguishing
phases of the three-wave coupling, namely the stable phase and the excited
explosive and auto-explosive phases. Two kinds of explosion mechanisms
three-wave coupling are found and described. The mechanism for the excited
explosive phase is normal because trigger energy is required in such a
mechanism and the threshold λth is proportional to δ2
(δ is the frequency
mismatch), whereas the anomalous mechanism for the auto-explosive phase
does not need any trigger – only proper changes of internal parameters
the absolute invariant J less than 27 are required.
In addition, the repetition
period of the explosive instability is given. Finally, the effects of weak
on the bifurcation structure of the explosive instability in three-wave
interactions are analysed.
The roles of metallic droplets, which generated from the cathodic arc spot holes in the technology of Cathodic Arc Plasma Deposition (CAPD), are investigated by SEM, TEM, image analysis apparatus, and electronic probe energy spectrum analysis. The results show that though many papers in recent years are devoted to eliminate them, the metallic droplets, including the macrodroplets, have many important positive roles in the preparation of alloy films: they are the main factor to transfer the original composition of alloy cathodic target to the alloy thick films; they preserve the high deposition rate of CAPD to form the basic characteristics of the microstructure and to affect the pore ratios of the films; they also preserve the high melting point elements in the alloy films, and therefore preserve the corrosion resistance of the alloy in the films. The macrodroplets can be eliminated by raising the substrate temperature properly, which is permitted in some cases, such as depositing alloy films onto middle carbon steel as an anticorrosion system, etc.
Part of the energy of low solar corona may be released and converted to plasma energy that may be the dominant source of solar flares. Recently, many physical mechanisms have been proposed to accelerate ions and electrons. In the magnetic mirror device of fusion research, ion cyclotron instability and the energetic ion losses have been discovered and the plasma becomes electron rich.
Crystallographic and X-ray powder diffraction data were derived from a sample of (Na0.5Bi0.5)TiO3 synthesized by standard ceramic techniques. The powder data were indexed on a monoclinic cell having the space group P2 or Pm, which differed from a previously reported rhombohedral cell.
For modern management and full resource sharing among libraries and scientific departments both in Chinese and worldwide observatories, we established the computer system of library management and information retrieval during the period 1984-1987.
The system is composed of ten component sub-systems:
1.Book ordering system. This system can produce orders for books and periodicals, balance accounts, produce statistics as well as claims for outstanding book orders.
2.Book cataloguing system. This system can catalogue books under certain rules while appending new records of books to the databases. It can also produce catalogue cards and produce written reports about the new books.
3.Book retrieval system has the ability to search for a specific book in several ways.
4.Book lending or circulation system. This system is a complete circulation system; including book lending, renewals, waiting lists, and recall of borrowed books.
5.Periodical management system. This system is in charge of processing of periodicals and magazines in the library, including cataloguing, management, and lending.
6.Scientific information retrieval system. One can retrieve scientific information by keywords or in many other ways.
7.Internal material booking system. It can make orders of internal materials, claims for materials outstanding and make exchanges with other observatories and institutions both in or outside the country.
8.Internal material management system. It can do the work that is analogous to that done with books and periodicals.
9.Information relationship system. It handles exchanges of information between institutions. Computer system of library management ... at Shaanxl 183
10.Scientific information network management system. It manages affairs within a certain information network.
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