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Stink bugs (Hemiptera, Pentatomidae) are major pests of soybean [Glycine max (L.) Merr.]. Biological control agents do not always succeed in reducing stink bug populations, so it become necessary to expand insecticides knowledge for integrated pest management. We evaluated the effectiveness of thiamethoxam + lambda-cyhalothrin, imidacloprid + beta-cyfluthrin, acetamiprid + cypermethrin, imidacloprid + carbaryl, trichlorfon, thiamethoxam, imidacloprid and spirotetramat + thiamethoxam for the control of phytophagous stink bugs and their side effects on generalist predators. Additionally, we determined the toxicity of the same set of insecticides on the egg parasitoid Telenomus podisi (Ashmead). The effectiveness of pest control and impact on predators was evaluated in field trials on small soybean plots during the 2011–12 and 2012–13 growing seasons. The adverse effects of insecticides on the emergence of T. podisi parasitized eggs of the red-banded stink bug Piezodorus guildinii (Westwood) were tested under laboratory and field conditions. During the two assessed years, P. guildinii was the predominant Pentatomidae species and spiders were the most frequent predators followed by several species of Heteroptera and Coccinellidae which feed on a wide range of insects. Thiamethoxam + lambda-cyhalothrin provided the highest level of control of stink bugs, but negatively affected predators. Under laboratory conditions, mortality of developing T. podisi larvae was significantly higher when exposed to trichlorfon, imidacloprid + carbaryl and neonicotinoids/pyrethroids combintaions. In contrast, no treatment affected T. podisi emergence under field conditions. Results suggest that under natural conditions, insecticidal sprays at recommended rates for stink bugs control do not affect T. podisi larvae but a mixture of thiamethoxam + lambda-cyhalothrin negatively affects generalist predators. [ABSTRACT FROM AUTHOR]

We have measured the intensities of fundamental and overtone transitions of CH stretching vibrations for a few selected paraffins, ketones, ethers, aromatic compounds, and haloforms. We have noticed some trends in the data, which we have correlated to the nature of the chemical bonds in the molecules. In order to account for both the fundamental and overtone intensity data, three different models for the CH bond electric dipole moments have been employed. [ABSTRACT FROM AUTHOR]

Quantum phase slips (QPS) are the primary excitations in one-dimensional superfluids and superconductors at low temperatures. They have been well characterized in most condensed-matter systems, and signatures of their existence have been recently observed in superfluids based on quantum gases too. In this review, we briefly summarize the main results obtained on the investigation of phase slips from superconductors to quantum gases. In particular, we focus our attention on recent experimental results of the dissipation in one-dimensional Bose superfluids flowing along a shallow periodic potential, which show signatures of QPS. This article is part of the themed issue 'Breakdown of ergodicity in quantum systems: from solids to synthetic matter'. [ABSTRACT FROM AUTHOR]

This paper describes a minimally invasive sensor platform for active and passive monitoring of human movements and physiological signals. Such a system is needed in cases where 24 × 7 monitoring is required, as in older adults with cognitive impairment, dementia and Alzheimer's disease. The passive monitoring systems used today are useful only in detecting events after they happen; the accuracy and speed of detection is questionable. The noninvasive nature of such systems does not bring trade off benefits to early detection and prevention of emergency incidents. We compare some existing sensor platforms and present our monitoring approach using minimally invasive wearable sensor device(s). With a Minimally Invasive Monitoring Sensor (MIMS), using advanced intelligent systems, we analyze the physiological signal data preceding potential emergency events in order to predict them quickly. The Virtual Hub is the core component of MIMS, which acts as a gateway between a monitored person and her/his caregivers, as well as a shared access point between active and passive sensing devices. Some preliminary results are presented here from our sleep-related fall study using two heterogeneous sensor systems. [ABSTRACT FROM PUBLISHER]

An experimental investigation of the kink instability is presented in a linear plasma column where one end is line-tied to the plasma source, and the other end is not line-tied and therefore free to slide over the surface of the end-plate. This latter boundary condition is a result of plasma sheath resistance that insulates, at least partially, the plasma from the end-plate. The helical m=1 kink mode is observed to grow when the plasma current exceeds a threshold and, close to the criticality, is characterized by an axial mode structure with maximum displacement at the free axial boundary. Azimuthal rotation of the mode is observed such that the helically kinked column always screws into the free axial boundary. The kink mode structure, rotation frequency and instability threshold are accurately reproduced by a recent kink theory [D. D. Ryutov et al., Phys. Plasmas 13, 032105 (2006)], which includes axial plasma flow and one end of the plasma column that is free to move due to a perfect non line-tying boundary condition which is experimentally verified. A brief review of the kink theory and its predictions for the boundary conditions relevant in the present experiments are presented. [ABSTRACT FROM AUTHOR]

In this paper we are concerned with the kink instability of a current-carrying plasma column whose radius a is much smaller than its length L. In the limit ax=ξx(z,t); ξy=ξy(z,t). Details of the internal structure of the column such as the radial distribution of the current, density, and axial flow can be lumped into some phenomenological parameters. This approach is particularly efficient in the problems with nonideal (sheath) boundary conditions (BC) at the end electrodes, with the finite plasma resistivity, and with a substantial axial flow. With the sheath BC imposed at one of the endplates, we find instability in the domain well below the classical Kruskal-Shafranov limit. The presence of an axial flow causes the onset of rotation of the kink and strong axial “skewness” of the eigenfunction, with the perturbation amplitude increasing in the flow direction. The limitations of the phenomenological approach are analyzed and are related to the steepness with which the plasma resistivity increases at the plasma boundary with vacuum. [ABSTRACT FROM AUTHOR]

Quasi-two-dimensional coalescence of two parallel cylindrical flux ropes and the development of three-dimensional merged structures are observed and studied in the reconnection scaling experiment [Furno et al., Rev. Sci. Instrum. 74, 2324 (2003)]. These experiments were conducted in a collisional regime with very strong guide magnetic field (Bguide>Breconnection), which can be adjusted independently of plasma density, current density, and temperature. During initial coalescence, a reconnection current sheet forms between the two flux ropes, and the direction of the current is opposite to the flux rope currents. The measured current sheet thickness is larger than the electron skin depth but smaller than the ion skin depth. Furthermore, the thickness does not vary for three different values of the strong external guide field. It is shown that the geometry of the observed current sheet is consistent with the Sweet–Parker model using a parallel Spitzer resistivity. The flux ropes eventually become kink unstable due to increasing current and fast-gated camera images show the development of three-dimensional merged structures. [ABSTRACT FROM AUTHOR]