Colorimetric sensor arrays for the detection of aqueous and gaseous analytes

The past decade has seen great interest concerning the development of artificial sensing devices; most notably optoelectronic tongues and noses. Utilizing previous research on how the mammalian gustatory and olfactory systems operate, significant progress in mimicking these systems has been realized. The turning point in this field of research has been the discovery that the mammalian senses of smell and taste are not based on specific receptors for each stimulant, but rather an array of semi-specific receptors that function simultaneously to produce a pattern. This pattern is interpreted in the brain, and classified either as a known stimulant or a new analyte similar to a known family of tastes or odors. As a predominantly visual species, we are programmed to acknowledge visible reports to chemical reactions over alternative reporting methods. Thus, colorimetric sensing can be more advantageous than other techniques and can allow for a greater number of chemical reactions to be probed. One colorimetric approach to sensing involves the immobilization of cross-responsive chemosensors capable of showing a color change upon reaction with analytes or mixtures of analytes. The employment of porous glasses as an immobilization technique has allowed for facile detection of analytes, both aqueous and gaseous, by allowing dye-analyte interactions to occur while preventing the sensor dye from escaping from the matrix. In this manner, colorimetric sensor arrays have been fashioned that are capable of discriminating among structurally similar compounds such as sugars, while retaining the ability to detect a wide range of analytes including toxic industrial chemicals. For aqueous detection, the newly developed porous glasses successfully immobilized otherwise soluble dyes that could detect changes in solution pH, caused by boronic acid-diol interactions. This allowed for rapid and sensitive detection and identification of natural and artificial sugars and sweeteners. Further experiments showed the array’s ability to differentiate between a selection of common table-top sweeteners such as Equal®, Sweet’N’Low®, Splenda®, and natural sugars. Gas sensing applications were made possible by slight modifications to the liquid sensing array. Hydrophobic silica precursors were added to limit the effect of changing humidity on the array, and printing onto flat, non-porous polymer surfaces gave fast and easy accessibility of incoming analytes to the immobilized indicators. Stable and sensitive colorimetric arrays for the detection and semi-quantification of a large number of toxic industrial chemicals was made possible by the inclusion of additional indicators capable of colorimetrically reporting changes in polarity, metal ligation, and redox reactions. The performances of these sensing arrays showed extremely low limits of detection, and were capable of identifying toxic gases within a large range of concentrations; ppb up to concentration immediately dangerous to life and health. In order to improve upon the detection limits for weakly responding gaseous analytes, alternative methods were developed. It was found that the immobilization of simple and stable color-changing dyes within chemically-reactive matrices could allow for facile and sensitive detection and quantification of formaldehyde. Optimization studies were carried out to assess the proper doping level of hydrophilic polymers with amine-appended polyethylene glycol

Adaptive Multi-Paddock Grazing of Cover Crops in Integrated Crop-Livestock Systems in Mediterranean Regions: a Review

Small-grain farming systems in Mediterranean climatic regions are characterized by poor quality soils, high climate variability, and resulting heavy agrochemical reliance. The integration of continuously grazed monocrop pasture phases has improved soil fertility, crop productivity, and mitigated financial risk. However, emerging sustainability issues such as herbicide resistance, inputs costs rising disproportionately to product prices, and increasing climate variability and predictability, drive the need for ongoing innovation in crop-livestock integration. The option of growing multi-species cover crops as a dual-forage and service crop is evaluated within Mediterranean climate contexts. Furthermore, the option of subjecting the cover crops to adaptive multi-paddock (AMP) grazing management as an alternative to the standard set stocking approach is discusse

OPTIMAL DESIGN OF A STEPPER-DRIVEN PLANAR LINKAGE USING ENTROPY METHODS

Stepper motors can be used to provide open-loop motion control in mechanisms. Unlike servo controlled mechanisms, however, the rotational drive input error cannot be resolved below the step error in the motor. Therefore, there is a fixed level of rotational position error that must be accepted in stepper driven mechanisms, and this rotational position error will inevitably propagate to kinematic position error in the mechanism. In this paper, the direct linearization method will be used to derive a model for kinematic position error based on uncertainty in the rotational input angle of a mechanism. Using this model, a method of constrained optimization to design a mechanism to minimize the effect of uncertain input conditions on kinematic position will be presented. The method is based on entropy minimization techniques that have been applied in a variety of robotic system applications. The method will be demonstrated in a case study, and will be shown to optimize the positioning reliability of a mechanism under input angle errors. The method will be shown to accurately predict drive error propagation, through comparison to Monte Carlo simulation. When coupled with entropy-based system reliability optimization methods, optimal mechansims can be synthesized in response to various positioning constraints

On Interferometric Duality in Multibeam Experiments

We critically analyze the problem of formulating duality between fringe visibility and which-way information, in multibeam interference experiments. We show that the traditional notion of visibility is incompatible with any intuitive idea of complementarity, but for the two-beam case. We derive a number of new inequalities, not present in the two-beam case, one of them coinciding with a recently proposed multibeam generalization of the inequality found by Greenberger and YaSin. We show, by an explicit procedure of optimization in a three-beam case, that suggested generalizations of Englert's inequality, do not convey, differently from the two-beam case, the idea of complementarity, according to which an increase of visibility is at the cost of a loss in path information, and viceversa.Comment: 26 pages, 1 figure, substantial changes in the text, new material has been added in Section 3. Version to appear in J.Phys.

Fermionic Determinant of the Massive Schwinger Model

A representation for the fermionic determinant of the massive Schwinger model, or $QED_2$, is obtained that makes a clean separation between the Schwinger model and its massive counterpart. From this it is shown that the index theorem for $QED_2$ follows from gauge invariance, that the Schwinger model's contribution to the determinant is canceled in the weak field limit, and that the determinant vanishes when the field strength is sufficiently strong to form a zero-energy bound state

QED in strong, finite-flux magnetic fields

Lower bounds are placed on the fermionic determinants of Euclidean quantum electrodynamics in two and four dimensions in the presence of a smooth, finite-flux, static, unidirectional magnetic field $B(r) =(0,0,B(r))$, where $B(r) \geq 0$ or $B(r) \leq 0$, and $r$ is a point in the xy-plane.Comment: 10 pages, postscript (in uuencoded compressed tar file

Usutu virus in blackbirds (Turdus merula) with clinical signs, a case study from northern Italy

Usutu virus (USUV) is a mosquito-borne virus belonging to the family Flaviviridae, genus Flavivirus. Natural transmission cycle of USUV involves mosquitoes and birds, so humans and other mammals are considered incidental hosts. In this study, USUV infection was diagnosed in all wild blackbirds, collected from July to September 2018 in a wildlife recovery center in the province of Bologna, in the Emilia-Romagna region, northern Italy. All blackbirds showed neurological clinical signs, such as overturning, pedaling, and incoordination. Moreover, the subjects died shortly after arriving at the hospitalization center. Virological investigations were performed by real-time PCR on frozen samples of the spleen, kidney, myocardium, and brain for the detection of Usutu (USUV) and West Nile (WNV) viruses. The small and large intestine were used as a matrix for the detection of Newcastle disease virus (NDV). All 56 subjects with neurological clinical signs were positive for USUV, only one subject (1.8%) tested positive for WNV, and no subject was positive for NDV. The most represented age class was class 1 J (58.9%), followed by class 3 (25.0%), and lastly from class 4 (16.1%). Most of the blackbirds before dying were in good (51.8%) and fair (39.3%) nutritional status, while only five subjects (8.9%) were cachectic. The USUV genomes detected in the blackbirds of this study fall within the sub-clade already called EU2 that has been detected since 2009 in the Emilia-Romagna region. Neurological clinical signs in USUV-affected blackbirds are still widely discussed and there are few works in the literature. Although our results require further studies, we believe them to be useful for understanding the clinical signs of Usutu virus in blackbirds, helping to increase the knowledge of this zoonotic agent in wild species and to understand its effect on the ecosystem. The goal of this study was to report—in the context of the regional passive surveillance program—the detection of USUV RNA in its most important amplifying host, the common blackbird, when showing clinical signs before death

Trampas de luz con panel pegante para la captura de adultos de Prodiplosis longifila (Diptera: Cecidomyiidae) en tomate

En Ica, en cultivo de tomate variedad “Dominator”, se evaluó la eficiencia de trampas de luz con panel pegante amarillo en la captura de la “mosquilla de los brotes” Prodiplosis longifila Gagne, y la infestación foliar y daños en frutos. Las trampas de luz con panel pegante con tubo fluorescente de luz blanca efectuaron la mayor captura de adultos de P. longifila con 27.56 adultos/semana, mostrando diferencias significativas respecto a los demás tratamientos. La más alta población de larvas de P. longifila/planta/semana se registró en el tratamiento trampa con panel sin dispositivo de luz con 39.25 larvas, resultando significativamente diferente a los demás, habiéndose registrado la menor población de larvas en el tratamiento trampa de luz con panel pegante con tubo fluorescente de luz blanca con 21.75 larvas. El mayor número de frutos dañados por P. longifila/planta/semana se registró en el tratamiento trampa con panel pegante sin dispositivo de luz con  8 frutos dañados, no mostrando diferencias significativas con el tratamiento trampa de luz con panel pegante con lámpara de regador a kerosene con 7.06 frutos dañados; mientras que el tratamiento con el  menor número de frutos dañados fue el de trampa de luz con panel pegante con tubo fluorescente de luz blanca con 4.75 frutos, habiendo resultado significativamente diferente con respecto a los demás. Este último tratamiento indicado registró el menor peso de frutos dañados por P. longifila/planta con 146.25 g, con diferencias significativas respecto a los otros.Palabras clave: Trampas de luz, Prodiplosis longifila, Lycopersicon esculentu

UMAP 2018 HUM (Holistic User Modeling) Workshop Chairs’ Preface & Organization

It is our great pleasure to welcome you to the UMAP 2018 HUM (Holistic User Modeling) Workshop. According to a recent claim by IBM, 90% of the data available today have been created in the last two years. This exponential growth of online information has given new life to research in the area of user modeling and personalization, since information about users' preferences, sentiment and opinions, as well as signals describing their physical and psychological state, can now be obtained by mining data gathered from many heterogeneous sources. We can distinguish two important classes of such data sources. One of these comes from recent trends in Quantified Self (QS) and Personal Informatics, which has emphasized the use of technology to collect personal data on different aspects of people's daily lives. These data can be internal states (such as mood or glucose level) or indicators of performance (such as the kilometers run). The purpose of collecting these data is self-monitoring, performed to gain self-knowledge or to obtain some change or improvement (behavioral, psychological, therapeutic, etc.). Often these data are also exploited for behavior change purposes, for example to increase the user's physical activity. The other key category comes from the enormous amount of textual content that is continuously spread on social networks. This has driven a strong research effort to investigate to what extent such data can be exploited to infer user interests, personality traits, emotions, and knowledge. Moreover, the recent phenomenon of (Linked) Open Data fueled this research line by making available a huge amount of machine-readable textual data that can be used to connect all the data points spread in different data silos under a uniform representation formalism. The main goal of the workshop is to investigate whether techniques for advanced content representation and methodologies for gathering and modeling personal data (e.g. physiological, behavioral) can be exploited to build a new generation of personalized and intelligent systems in domains as diverse as health, learning, behavior change, e-government, smart cities (e.g., by combining mood data and music preferences data to provide recommendations on music to be listened)