Global spatial optimization with hydrological systems simulation: appliication to land-use allocation and peak runoff minimization

A general methodology is presented to integrate complex simulation models of hydrological systems into optimization models, as an alternative to scenario-based approaches. A gradient-based hill climbing algorithm is proposed to reach locally optimal solutions from distinct starting points. The gradient of the objective function is estimated numerically with the simulation model. A statistical procedure based on the Weibull distribution is used to build a confidence interval for the global optimum. The methodology is illustrated by an application to a small watershed in Ohio, where the decision variables are related to land-use allocations and the objective is to minimize peak runoff. The results suggest that this specific runoff function is convex in terms of the land-use variables, and that the global optimum has been reached. Modeling extensions and areas for further research are discussed

Reconstruction of spectral solar irradiance since 1700 from simulated magnetograms

We present a reconstruction of the spectral solar irradiance since 1700 using the SATIRE-T2 (Spectral And Total Irradiance REconstructions for the Telescope era version 2) model. This model uses as input magnetograms simulated with a surface flux transport model fed with semi-synthetic records of emerging sunspot groups. We used statistical relationships between the properties of sunspot group emergence, such as the latitude, area, and tilt angle, and the sunspot cycle strength and phase to produce semi-synthetic sunspot group records starting in the year 1700. The semisynthetic records are fed into a surface flux transport model to obtain daily simulated magnetograms that map the distribution of the magnetic flux in active regions (sunspots and faculae) and their decay products on the solar surface. The magnetic flux emerging in ephemeral regions is accounted for separately based on the concept of extended cycles whose length and amplitude are linked to those of the sunspot cycles through the sunspot number. The magnetic flux in each surface component (sunspots, faculae and network, and ephemeral regions) was used to compute the spectral and total solar irradiance between the years 1700 and 2009. This reconstruction is aimed at timescales of months or longer although the model returns daily values. We found that SATIRE-T2, besides reproducing other relevant observations such as the total magnetic flux, reconstructs the total solar irradiance (TSI) on timescales of months or longer in good agreement with the PMOD composite of observations, as well as with the reconstruction starting in 1878 based on the RGO-SOON data. The model predicts an increase in the TSI of 1.2[+0.2, -0.3] Wm-2 between 1700 and the present. The spectral irradiance reconstruction is in good agreement with the UARS/SUSIM measurements as well as the Lyman-alpha composite.Comment: 13 pages, 10 figure

UV solar irradiance in observations and the NRLSSI and SATIRE-S models

Total solar irradiance and UV spectral solar irradiance have been monitored since 1978 through a succession of space missions. This is accompanied by the development of models aimed at replicating solar irradiance by relating the variability to solar magnetic activity. The NRLSSI and SATIRE-S models provide the most comprehensive reconstructions of total and spectral solar irradiance over the period of satellite observation currently available. There is persistent controversy between the various measurements and models in terms of the wavelength dependence of the variation over the solar cycle, with repercussions on our understanding of the influence of UV solar irradiance variability on the stratosphere. We review the measurement and modelling of UV solar irradiance variability over the period of satellite observation. The SATIRE-S reconstruction is consistent with spectral solar irradiance observations where they are reliable. It is also supported by an independent, empirical reconstruction of UV spectral solar irradiance based on UARS/SUSIM measurements from an earlier study. The weaker solar cycle variability produced by NRLSSI between 300 and 400 nm is not evident in any available record. We show that although the method employed to construct NRLSSI is principally sound, reconstructed solar cycle variability is detrimentally affected by the uncertainty in the SSI observations it draws upon in the derivation. Based on our findings, we recommend, when choosing between the two models, the use of SATIRE-S for climate studies

Surface Acoustic Wave Driven Microchannel Flow

We demonstrate that the propagation of surface acoustic waves, arising from the excitation of the acoustic field on a piezoelectric crystal (lithium niobate) substrate, along the sidewalls of microchannels (50 μm or 280 μm wide and 200 μm deep) fabricated in the substrate, can give rise to throughflow with velocities of the order 10 mm/s. This streaming flow in the direction along which the surface acoustic wave propagates is a result of the leakage of acoustic radiation from the substrate walls into the fluid. Good agreement is obtained between these preliminary experimental results with those from numerical simulations of the classical acoustic streaming model. In any case, these results show the potential of surface acoustic wave micropumps to be an effective fluid-driving mechanism for microfluidic devices

Simple scheme for expanding a polarization-entangled W state by adding one photon

We propose a simple scheme for expanding a polarization-entangled W state. By mixing a single photon and one of the photons in an n-photon W state at a polarization-dependent beam splitter (PDBS), we can obtain an (n+1)-photon W state after post-selection. Our scheme also opens the door for generating n-photon W states using single photons and linear optics.Comment: 3 pages, 2 figure

Evaluation of cognitive function in adult rhesus monkeys using the finger maze test

In research on cognitive function, the use of experimental animals is essential for the study of human cognitive processes and mechanisms. Furthermore, non-human primates are necessary for understanding higher cognitive functions in humans. However, there are few cognitive function tests available for non-human primates, Thus, we modified a finger maze test for application to non-human primates. In this study, we assessed learning and memory in 12 adult rhesus monkeys using a finger maze test that was developed to assess cognitive functions in captive non-human primates. The monkeys were trained with moving rewards indicating the correct direction, which allowed the monkeys to obtain the reward. Following training, subjects completed a learning trial and a memory trial two months later. Although the time required for training varied among the monkeys, 11 out of 12 monkeys completed the training and achieved a high success rate in the learning trial as well as in the memory trial conducted 2 months later. This is the first study to apply the finger maze test to adult rhesus monkeys. The finger maze test enabled us to assess learning and memory in several adult rhesus monkeys simultaneously

Microfluidic Channel Fabrication in Lithium Niobate using Focused Ion Beam

Microfluidic channels are fabricated in lithium niobate (LN) by Focused Ion Beam (FIB) milling. 127.68° axis rotated Y-cut (SAW grade) and Z-cut LN wafers are used. Material removal rate is 0.34±0.02 µm3/nC for Y-cut sample and 0.30 ± 0.02µm/nC for Z-cut sample. Experimental results show that the material removal rate decreases at high ion doses and high aspect ratios due to the increased significance of material deposition at these conditions. We also demonstrate the suitability of FIB-milled nanochannels for micro/nanofluidic applications

Clavicle fracture nonunion in the paediatric population: a systematic review of the literature.

Aims: Clavicle fracture nonunions are extremely rare in children. The aim of this systematic review was to assess what factors may predispose children to form clavicle fracture nonunions and evaluate the treatment methods and outcomes. Methods: We performed a systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, aiming to find papers reporting clavicle fracture nonunion in children under the age of 18 years. Data was collected on patient demographics, fracture type, mechanism of injury (MOI), surgical intervention and reported outcome. Two independent reviewers evaluated all the data. Results: A total of 13 articles reporting 21 cases of clavicle fracture nonunion were identified. The mean age at time of injury was 11.4 years (4 to 17). Falls were the most common MOI. The majority of nonunions occurred after displaced fractures on the right side. Six were refractures. Mean time of presentation following injury was 13.5 months (4 to 60). In all, 16 were treated surgically. Radiographic union was eventually achieved in 12 cases, with functional outcome satisfactory in all cases. Conclusion: Clavicle nonunion is an extremely rare but possible complication in children. The majority occur after displaced right-sided fractures or refractures and present around one year after injury. Surgical fixation provides good radiographic healing and functional outcomes. Level of evidence: IV