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We report on the use of leaf diffuse reflectance spectroscopy for plant disease detection. A smartphone-operated, compact diffused reflectance spectrophotometer is used for field collection of leaf diffuse reflectance spectra to enable pre-symptomatic detection of the progression of potato late blight disease post inoculation with oomycete pathogen Phytophthora infestans. Neural-network-based analysis predicts infection with >96% accuracy, only 24 h after inoculation with the pathogen, and nine days before visual late blight symptoms appear. Our study demonstrates the potential of using portable optical spectroscopy in tandem with machine learning analysis for early diagnosis of plant diseases.

Located in the midline lamina terminalis of the anterior wall of the third ventricle, the median preoptic nucleus is a thin elongated nucleus stretching around the rostral border of the anterior commissure. Its neuronal elements, composed of various types of excitatory glutamatergic and inhibitory GABAergic neurons, receive afferent neural signals from (1) neighboring subfornical organ and organum vasculosum of the lamina terminalis related to plasma osmolality and hormone concentrations, e.g., angiotensin II; (2) from peripheral sensors such as arterial baroreceptors and cutaneous thermosensors. Different sets of these MnPO glutamatergic and GABAergic neurons relay output signals to hypothalamic, midbrain, and medullary regions that drive homeostatic effector responses. Included in the effector responses are (1) thirst, antidiuretic hormone secretion and renal sodium excretion that subserve osmoregulation and body fluid homeostasis; (2) vasoconstriction or dilatation of skin blood vessels, and shivering and brown adipose tissue thermogenesis for core temperature homeostasis; (3) inhibition of hypothalamic and midbrain nuclei that stimulate wakefulness and arousal, thereby promoting both REM and non-REM sleep; and (4) activation of sympathetic pathways that drive vasoconstriction and heart rate to maintain arterial pressure and the perfusion of vital organs. The small size of MnPO belies its massive homeostatic significance.

Fe-based superconductors exhibit a diverse interplay between charge, orbital, and magnetic ordering. Variations in atomic geometry affect electron hopping between Fe atoms and the Fermi surface topology, influencing magnetic frustration and the pairing strength through changes of orbital overlap and occupancies. Here, we experimentally demonstrate a systematic approach to realize superconductivity without chemical doping in BaFe(2)As(2), employing geometric design within an epitaxial heterostructure. We control both tetragonality and orthorhombicity in BaFe(2)As(2) through superlattice engineering, which we experimentally find to induce superconductivity when the As−Fe−As bond angle approaches that in a regular tetrahedron. This approach to superlattice design could lead to insights into low-dimensional superconductivity in Fe-based superconductors.

Electronic nematicity in iron pnictide materials is coupled to both the lattice and the conducting electrons, which allows both structural and transport observables to probe nematic fluctuations and the order parameter. Here we combine simultaneous transport and X-ray diffraction measurements with in-situ tunable strain (elasto X-ray diffraction) to measure the temperature dependence of the shear modulus and elastoresistivity above the nematic transition and the spontaneous orthorhombicity and resistivity anisotropy below the nematic transition, all within a single sample of Ba(Fe

We report on the epitaxial strain-driven electronic and antiferromagnetic modulations of a pseudospin-half square-lattice realized in superlattices of (SrIrO_{3})_{1}/(SrTiO_{3})_{1}. With increasing compressive strain, we find the low-temperature insulating behavior to be strongly suppressed with a corresponding systematic reduction of both the Néel temperature and the staggered moment. However, despite such a suppression, the system remains weakly insulating above the Néel transition. The emergence of metallicity is observed under large compressive strain but only at temperatures far above the Néel transition. These behaviors are characteristics of the Slater-Mott crossover regime, providing a unique experimental model system of the spin-half Hubbard Hamiltonian with a tunable intermediate coupling strength.

High-speed electronics require epitaxial films with exceptionally high carrier mobility at room temperature (RT). Alkaline-earth stannates with high RT mobility show outstanding prospects for oxide electronics operating at ambient temperatures. However, despite significant progress over the last few years, mobility in stannate films has been limited by dislocations because of the inability to grow fully coherent films. Here, we demonstrate the growth of coherent, strain-engineered phases of epitaxial SrSnO

Atomic layer controlled growth of epitaxial thin films of unconventional superconductors opens the opportunity to discover novel high temperature superconductors. For instance, the interfacial atomic configurations may play an important role in superconducting behavior of monolayer FeSe on SrTiO

Magnetic anisotropy (MA) is one of the most important material properties for modern spintronic devices. Conventional manipulation of the intrinsic MA, i.e., magnetocrystalline anisotropy (MCA), typically depends upon crystal symmetry. Extrinsic control over the MA is usually achieved by introducing shape anisotropy or exchange bias from another magnetically ordered material. Here we demonstrate a pathway to manipulate MA of 3d transition-metal oxides (TMOs) by digitally inserting nonmagnetic 5d TMOs with pronounced spin-orbit coupling (SOC). High-quality superlattices comprising ferromagnetic La2/3Sr1/3MnO3 (LSMO) and paramagnetic SrIrO3 (SIO) are synthesized with the precise control of thickness at the atomic scale. Magnetic easy-axis reorientation is observed by controlling the dimensionality of SIO, mediated through the emergence of a novel spin-orbit state within the nominally paramagnetic SIO.

We present evidence that the metal-insulator transition (MIT) in a tensile-strained NdNiO3 (NNO) film is facilitated by a redistribution of electronic density and that it neither requires Ni charge disproportionation nor a symmetry change [U. Staub et al., Phys. Rev. Lett. 88, 126402 (2002); R. Jaramillo et al., Nat. Phys. 10, 304 (2014)]. Given that epitaxial tensile strain in thin NNO films induces preferential occupancy of the e(g) d(x(2)-y(2)) orbital we propose that the larger transfer integral of this orbital state with the O 2p orbital state mediates a redistribution of electronic density from the Ni atom. A decrease in the Ni d(x(2)-y(2)) orbital occupation is directly observed by resonant inelastic x-ray scattering below the MIT temperature. Furthermore, an increase in the Nd charge occupancy is measured by x-ray absorption at the Nd L(3) edge. Both spin-orbit coupling and crystal field effects combine to break the degeneracy of the Nd 5d states, shifting the energy of the Nd e(g) d(x(2)-y(2)) orbit towards the Fermi level, allowing the A site to become an active acceptor during the MIT. This work identifies the relocation of electrons from the Ni 3d to the Nd 5d orbitals across the MIT. We propose that the insulating gap opens between the Ni 3d and O 2p states, resulting from Ni 3d electron localization. The transition seems to be neither a purely Mott-Hubbard transition nor a simple charge transfer.

Conventional survey methods have efficiencies in medium to low intensity survey because they use relationships between soil properties and more readily observable environmental features as a basis for mapping. However, the implicit predictive models are qualitative, complex and rarely communicated in a clear manner. The possibility of developing an explicit analogue of conventional survey practice suited to medium to low intensity surveys is considered. A key feature is the use of quantitative environmental variables from digital terrain analysis and airborne gamma radiometric remote sensing to predict the spatial distribution of soil properties. The use of these technologies for quantitative soil survey is illustrated using an example from the Bago and Maragle State Forests in southeastern Australia. A design-based, stratified, two-stage sampling scheme was adopted for the 50,000 ha area using digital geology, landform and climate as stratifying variables. The landform and climate variables were generated using a high resolution digital elevation model with a grid size of 25 m. Site and soil data were obtained from 165 sites. Regression trees and generalised linear models were then used to generate spatial predictions of soil properties using digital terrain and gamma radiometric survey data as explanatory variables. The resulting environmental correlation models generate spatial predictions with a fine grain unmatched by comparable conventional survey methods. Example models and spatial predictions are presented for soil profile depth, total phosphorus and total carbon. The models account for 42%, 78% and 54% of the variance present in the sample respectively. The role of spatial dependence, issues of scale and landscape complexity are discussed along with the capture of expert knowledge. It is suggested that environmental correlation models may form a useful trend model for various forms of kriging if spatial dependence is evident in the residuals of the model.

Explicit and quantitative models for the spatial prediction of soil and landscape attributes are required for environmental modelling and management. In this study, advances in the spatial representation of hydrological and geomorphological processes using terrain analysis techniques are integrated with the development of a field sampling and soil-landscape model building strategy. Statistical models are developed using relationships between terrain attributes (plan curvature, compound topographic index, upslope mean plan curvature) and soil attributes (A horizon depth, Solum depth, E horizon presence/absence) in an area with uniform geology and geomorphic history. These techniques seem to provide appropriate methodologies for spatial prediction and understanding soil landscape processes.

Nutritional surveys in New South Wales Pinus radiata plantations have shown differences in both foliage and soil boron status, particularly as a result of variations in soil parent materials. Plantations on acid igneous parent materials are particularly susceptible to the development of B deficiency, which appears to be further exacerbated bu soil/landscape relationships, water stress and certain management practices. Boron deficiency in P. radiata on acid igneous soils at Sunny Corner State Forest, N.S.W., was particularly noticeable on lower slopes which usually have relatively high available moisture. These lower-slope soils had severely leached surface horizons, less extractable B, and fewer B-sorption characteristics than the upper sections of the soil catena. These soil properties also adversely affect the capacity of these soils to retain either Na-borate or Ca-borate fertilizers (borax and colemanite, respectively). For equal amounts of B, up to 95% of the borax applied to in-situ soil columns rapidly moved beyond the top 0.3 m of the soil profiles within 21 months, while less than 16% of the colemanite had moved beyond the columns. Leached surface soils of the lower-slope site retained lesser amounts of either B-fertilizer. Colemanite offers the most cost-effective means of maintaining adequate levels of soil-B in these soil types due to its lower solubility. Management of B deficiency in P. radiata involves appropriate site selection, forest management practices and fertilizers usage.

A 0.13um CMOS mixed signal 802.11a/b/g baseband PHY IC, with per-packet receive diversity, 802.11h radar/DFS support and an MRC/MIMO coprocessor interface, is described. Required receive C/N is 5dB at 6 Mbps, and 20dB at 54 Mbps. Residual packet error rate is less than 4% for 54 Mbps and 0.1% for 6 Mbps link data rates in a 50ns delay spread channel. The 4.75×4.75mm chip, fabricated in 1P7M 0.13um CMOS, has 8M transistors and dissipates under 31mW in sleep, 206mW in Tx, and 362mW in Rx.

This paper describes how an FPGA based prototype environment aided the development of two multi-million gate ASICs: an IEEE 802.11 medium access controller and an IEEE 802.11a/b/g physical layer processor. Prototyping the ASICs on a reconfigurable platform enabled concurrent development by the hardware and software teams, and provided a high degree of confidence in the designs. The capabilities of modern FPGAs and their development tools allowed us to easily and quickly retarget the complex ASICs into FPGAs, enabling us to integrate the prototyping effort into our design flow from the start of the project. The effect was to accelerate the development cycle and generate an ASIC which had been through one pass of beta testing before tape-out.

This chip, fabricated in a 0.25/spl mu/m 5M1P CMOS process with 3.7M transistors, implements a fully-compliant IEEE 802.11a PHY modem. The IEEE 802.11a standard provides for wireless local area networks (WLANs) with a physical layer based on coded orthogonal frequency domain multiplexing (COFDM) modulation, delivering data rates up to 54Mb/s, operating in the 5GHz UNII frequency bands. The article outlines the role of a physical layer (PHY) modem in such a WLAN system. The PHY modem lies between a medium access controller (MAC) and a 5GHz radio transceiver, and is responsible for demodulating and modulating a baseband analog signal with data from the MAC. In 802.11a the baseband signal is a 64 subcarrier COFDM signal with BPSK, QPSK, QAM16 or QAM64 modulated subcarriers.

A method has been developed for applying classical minimization techniques to forms of algebraic performance indices for use in optimal adaptive control systems. Essentially, the derivative of a general objective function is constrained to be equal to the integrand of a desired integral performance index. This generates a set of linear algebraic equations, the solution of which results in an algebraic objective function which is explicit in the system parameters. Derivatives of this function can be taken with respect to the controllable parameters, set equal to zero, and solved for the settings which minimize the performance index over time. Alternatively, the function itself may be searched for its minimum on the controllable parameters. The method has been applied to a stirred tank chemical reactor with an exothermic first-order reaction in which heat removal was accomplished by cooling coils. The cooling water flow rate was controlled by a proportional-plus-integral controller and by a three-mode controller. The adaptive control system adjusted the controller settings periodically. The plant, which was third-order, was controlled to a second-order dynamic reference model. The responses to both initial offsets (start-up problem) and disturbances in system parameters were investigated. In all cases, the adaptive control system performance was markedly superior to that for the unadapted, ordinary feedback control system.

Trees are being established on substantial areas of Australian farmland, often extending into districts where forestry has not been previously practiced. Irrespective of purpose-wood production, increased water use, erosion control, habitat restoration, carbon sequestration or bio-energy production-the benefits of farm forestry depend on tree survival and adequate growth. Site assessment has been mainly used for the prediction of tree performance but it can be extended to form the basis for site-specific management. Site assessment needs to provide information on species and management inputs suitable to a site's inherent environmental attributes so that the aim of maximum profitability can be achieved while maintaining a sustainable use of resources. A new site concept for farm forestry is presented that reflects these factors. This new site concept is defined as the integrated effect of environmental factors that influence the potential growth of a particular tree genotype and affect the soil management of that stand of trees to produce a particular product or output. This concept of site is environment-based, independent of the presence of trees, and includes an explicit acknowledgement of a hierarchy of scale (both spatial and temporal) and how it affects what environmental factors need to be assessed. The goal for site assessment for farm forestry is to develop pragmatic, robust and quantitative interpretations from the measured data to aid multiple aspects of plantation management. A pragmatic approach to field survey is required, with data gathering (whether morphological, analytical or electronic) being based on demonstrated benefit rather than routine prescription, guess-work or tradition. Site assessment needs to be linked to well-designed species trials and permanent growth plots so continual evolution and improvement of edaphic and silvicultural relationships can be incorporated into future modifications.