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We studied the magnetic ordering of thin films and bulk crystals of rutile RuO$_2$ using resonant X-ray scattering across the Ru L$_2$ absorption edge. Combining polarization analysis and azimuthal-angle dependence of the magnetic Bragg signal, we have established the presence of G-type antiferromagnetism in RuO$_2$ with T$_N$ $>$ 300 K. In addition to revealing a spin-ordered ground state in the simplest ruthenium oxide compound, the persistence of magnetic order even in nanometer-thick films lays the ground for potential applications of RuO$_2$ in antiferromagnetic spintronics., 5 pages, 4 figures

International audience; Surface layer temperature inversion (SLTI), a warm layer sandwiched between surface and subsurface colder waters, has been reported to frequently occur in conjunction with barrier layers in the Bay of Bengal (BoB), with potentially commensurable impacts on climate and postmonsoon tropical cyclones. Lack of systematic measurements from the BoB in the past prevented a thorough investigation of the SLTI spatiotemporal variability, their formation mechanisms, and their contribution to the surface temperature variations. The present study benefits from the recent Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA) buoys located in BoB along 90°E at 4°N, 8°N, 12°N, and 15°N over the 2006–2014 period. Analysis of data from these RAMA buoys indicates that SLTI forms after the summer monsoon and becomes fully developed during winter (December–February). SLTI exhibits a strong geographical dependency, with more frequent (80% times during winter) and intense inversions (amplitude, ΔT ∼ 0.7°C) occurring only in the northern BoB compared to central and southern Bay. SLTI also exhibits large interannual and intraseasonal variations, with intraseasonal amplitude significantly larger (ΔT ∼ 0.44°C) than the interannual amplitude (∼0.26°C). Heat budget analysis of the mixed layer reveals that the net surface heat loss is the most dominant process controlling the formation and maintenance of SLTI. However, there are instances of episodic advection of cold, low-saline waters over warm-saline waters leading to the formation of SLTI as in 2012–2013. Vertical processes contribute significantly to the mixed layer heat budget during winter, by warming the surface layer through entrainment and vertical diffusion.

Wireless sensors have several constraints, such as a short transmission range, poor processing capabilities, and a limited available energy. Our goal is to design an energy efficient sensor network by exploiting the concept of collaborative signal processing. We consider a network composed of multiple sensor nodes, each of which corresponds to a processor. By using an appropriate collaborative computational algorithm and communication scheme, we make sensors operate as a Distributed Digital Signal Processor (DDSP) and generate the desired results. The benefit of such an approach is twofold: (i) the energy and computational limitations of the individual sensors can be overcome, and (ii) for a given level of processing complexity, the energy efficiency of the overall network can increase significantly. We apply the DDSP approach to the Fast Fourier Transform algorithm, and derive results showing the improvement in performance that can be obtained through the proposed technique. Moreover, we study the existing trade-off between energy saving, data latency and number of employed sensors.

Wireless networking has experienced a great deal of popularity, and significant advances have been made in wireless technology. However, energy efficiency of radio communication systems is still a critical issue due to the limited battery capacity of portable devices. In this paper, we deal with the charge recovery effect that takes place in electrochemical cells and show how we can take advantage of this mechanism to increase the energy delivered by a battery. Then, we present energy-aware traffic shaping techniques, as well as scheduling and routing algorithms, which exploit the battery recovery effect.

This paper presents the development and validation of a computational scheme for an analysis of activated charcoal-nitrogen adsorption cryocoolers. Using this procedure a comparative analysis of four samples of charcoal is carried out. It is shown that the specific power (SP) of the cryocooler is governed by the packing density achievable in addition to the charcoal adsorption characteristics, cycle operating pressures and temperatures. A 77 K cryocooler with an SP of the order of 400 W W-1 can be achieved with a charcoal packing density of about 1 g cm(-3) for several available charcoals. The analysis shows that Fluka and BCGI specimens can yield promising results under the present technologically realizable conditions.

Rabbits were poisoned by the intraperitoneal injection of plasmocid dihydroiodide at a dosage of 80 mg. per kg. body weight. Animals were euthanatized 1, 2, 5, 7, 9, 12, 24 and 48 hours after plasmocid injection and serum and diaphragmatic muscle collected. The serum was examined for its serum glutamic oxalacetic transaminase (SGOT) and creatine phosphokinase (CPK) concentrations. The diaphragm was sectioned and examined for the progression of morphologic alterations. It was found that SGOT and CPK concentrations were similar in their time and duration of elevation and that the serum CPK elevations closely paralleled the occurrence and degree of morphologic muscle degeneration. It appears that CPK is the most specific clinical biochemical test for the detection of muscle necrosis available at this time.

Metadata only record Widespread skeletal myodegeneration in cattle was associated with a disease syndrome characterized by an afebrile course, abnormally dark red urine, incoordination, recumbency, and death. The plants Cassia occidentalis or Cassia obtusifolia grew in the pastures and has been grazed by affected cattle, and appeared to have caused the disease.

In this paper, we address the problem of energy-conscious cache placement in wireless ad hoc networks. We consider a network comprising a server with an interface to the wired network, and some nodes requiring access to the information stored at the server. In order to reduce access latency in such a communication environment, an effective strategy is caching the server information at some nodes distributed across the network. Caching, however, can considerably impact the system energy expenditure; for instance, disseminating information incurs additional energy burden. Since wireless devices have limited amounts of available energy, we need to design caching strategies that optimally trade-off between energy consumption and access latency. We pose our problem as an integer linear program. We show that this problem is the same as a special case of the connected facility location problem, which is known to be NP-hard. We devise a polynomial time algorithm which provides a sub-optimal solution. The proposed algorithm applies to any arbitrary network topology and can be implemented in a distributed and asynchronous manner. In the case of a tree topology, our algorithm gives the optimal solution. In the case of an arbitrary topology, it finds a feasible solution with an objective function value within a factor of 6 of the optimal value. This performance is very close to the best approximate solution known today, which is obtained in a centralized manner. We compare the performance of our algorithm against three candidate caching schemes, and show via extensive simulation that our algorithm consistently outperforms these alternative schemes.