Simple and Complex Metafluids and Metastructures with Sharp Spectral Features in a Broad Extinction Spectrum: Particle-Particle Interactions and Testing the Limits of the Beer-Lambert Law

Metallic nanocrystals (NCs) are useful instruments for light manipulation around the visible spectrum. As their plasmonic resonances depend heavily on the NC geometry, modern fabrication techniques afford a great degree of control over their optical responses. We take advantage of this fact to create optical filters in the visible-near IR. Our systems show an extinction spectrum that covers a wide range of wavelengths (UV to mid-IR), while featuring a narrow transparency band around a wavelength of choice. We achieve this by carefully selecting the geometries of a collection of NCs with narrow resonances that cover densely the spectrum from UV to mid-IR except for the frequencies targeted for transmission. This fundamental design can be executed in different kinds of systems, including a solution of colloidal metal NCs (metafluids), a structured planar metasurface or a combination of both. Along with the theory, we report experimental results, showing metasurface realizations of the system, and we discuss the strengths and weaknesses of these different approaches, paying particular attention to particle-particle interaction and to what extent it hinders the intended objective by shifting and modifying the profile of the planned resonances through the hybridization of their plasmonic modes. We have found that the Beer-Lambert law is very robust overall and is violated only upon aggregation or in configurations with nearly-touching NCs. This striking property favors the creation of metafluids with a narrow transparency window, which are investigated here.Comment: Includes Supplementary Information, totaling 32 pages and 8 figure

On low-power analog implementations of particle filters for target tracking

We propose a low-power, analog and mixed-mode, implementation of particle filters. Low-power analog implementation of nonlinear functions such as exponential and arctangent functions is done using multiple-input translinear element (MITE) networks. These nonlinear functions are used to calculate the probability densities in the particle filter. A bearings-only tracking problem is simulated to present the proposed low-power implementation of the particle filter algorithm

The ABCD of obesity: An EASO position statement on a diagnostic term with clinical and scientific implications

Obesity is a frequent, serious, complex, relapsing, and chronic disease process that represents a major public health problem. The coining of obesity as an adiposity-based chronic disease (ABCD) is of particular relevance being in line with EASO’s proposal to improve the International Classification of Diseases ICD-11 diagnostic criteria for obesity based on three dimensions, namely etiology, degree of adiposity, and health risks. The body mass index as a unique measurement of obesity does not reflect the whole complexity of the disease. Obesity complications are mainly determined by 2 pathological processes, i.e., physical forces (fat mass disease) as well as endocrine and immune responses (sick fat disease), which are embedded in a cultural and physical context leading to a specific ABCD stage

The Shadows of the Past

We examined associations between two orientations based on historical group trauma, a form of enduring group victimhood (Perpetual Ingroup Victimhood Orientation [PIVO]) and the belief that one’s group might itself become a victimizer (Fear of Victimizing [FOV]), and attitudes, cognitions, and emotions related to intergroup conflicts. PIVO was positively and FOV was negatively related to aggressive attitudes and emotions toward the outgroup (Studies 1a-1c, Israeli–Palestinian conflict), and to the attribution of responsibility for a series of hostilities to the outgroup (Study 3, Israeli–Palestinian conflict). PIVO was negatively and FOV positively related to support for forgiveness and reconciliation (Study 2, Northern Ireland conflict). In Experimental Study 4, FOV predicted greater accuracy in remembering harm, regardless of victims’ group identity, whereas PIVO was associated with reduced accuracy only when victims were Palestinians (outgroup members). Taken together, these findings indicate that both orientations have a significant impact on intergroup conflicts and their resolution

European association for the study of obesity position statement on the global COVID-19 pandemic

COVID-19, the infectious disease caused by the coronavirus SARS-CoV-2, was declared a pandemic by the World Health Organization on March 12, 2020. The European Association for the Study of Obesity (EASO), as a scientific and medical society dedicated to the promotion of health and well-being, is greatly concerned about this global health challenge and its significant impacts on individuals, families, communities, health systems, nations, and wider society

Type-II Colloidal Quantum Wells: CdSe/CdTe Core/Crown Heteronanoplatelets

Solution-processed quantum wells, also known as colloidal nanoplatelets (NPLs), are emerging as promising materials for colloidal optoelectronics. In this work, we report the synthesis and characterization of CdSe/CdTe core/crown NPLs exhibiting a Type-II electronic structure and Type-II specific optical properties. Here, based on a core-seeded approach, the CdSe/CdTe core/crown NPLs were synthesized with well-controlled CdTe crown coatings. Uniform and epitaxial growth of CdTe crown region was verified by using structural characterization techniques including transmission electron microscopy (TEM) with quantitative EDX analysis and X-ray diffraction (XRD). Also the optical properties were systematically studied in these Type-II NPLs that reveal strongly red-shifted photoluminescence (up to similar to 150 nm) along with 2 orders of magnitude longer fluorescence lifetimes (up to 190 ns) compared to the Type-I NPLs owing to spatially indirect excitons at the Type-II interface between the CdSe core and the CdTe crown regions. Photoluminescence excitation spectroscopy confirms that this strongly red-shifted emission actually arises from the CdSe/CdTe NPLs. In addition, temperature-dependent time-resolved fluorescence spectroscopy was performed to reveal the temperature-dependent fluorescence decay kinetics of the Type-II NPLs exhibiting interesting behavior. Also, water-soluble Type-II NPLs were achieved via ligand exchange of the CdSe/CdTe core/crown NPLs by using 3-mercaptopropionic acid (MPA), which allows for enhanced charge extraction efficiency owing to their shorter chain length and enables high quality film formation by layer-by-layer (LBL) assembly. With all of these appealing properties, the CdSe/CdTe core/crown heterostructures having Type-II electronic structure presented here are highly promising for light-harvesting applications

Mice Doubly-Deficient in Lysosomal Hexosaminidase A and Neuraminidase 4 Show Epileptic Crises and Rapid Neuronal Loss

Tay-Sachs disease is a severe lysosomal disorder caused by mutations in the HexA gene coding for the α-subunit of lysosomal β-hexosaminidase A, which converts GM2 to GM3 ganglioside. Hexa−/− mice, depleted of β-hexosaminidase A, remain asymptomatic to 1 year of age, because they catabolise GM2 ganglioside via a lysosomal sialidase into glycolipid GA2, which is further processed by β-hexosaminidase B to lactosyl-ceramide, thereby bypassing the β-hexosaminidase A defect. Since this bypass is not effective in humans, infantile Tay-Sachs disease is fatal in the first years of life. Previously, we identified a novel ganglioside metabolizing sialidase, Neu4, abundantly expressed in mouse brain neurons. Now we demonstrate that mice with targeted disruption of both Neu4 and Hexa genes (Neu4−/−;Hexa−/−) show epileptic seizures with 40% penetrance correlating with polyspike discharges on the cortical electrodes of the electroencephalogram. Single knockout Hexa−/− or Neu4−/− siblings do not show such symptoms. Further, double-knockout but not single-knockout mice have multiple degenerating neurons in the cortex and hippocampus and multiple layers of cortical neurons accumulating GM2 ganglioside. Together, our data suggest that the Neu4 block exacerbates the disease in Hexa−/− mice, indicating that Neu4 is a modifier gene in the mouse model of Tay-Sachs disease, reducing the disease severity through the metabolic bypass. However, while disease severity in the double mutant is increased, it is not profound suggesting that Neu4 is not the only sialidase contributing to the metabolic bypass in Hexa−/− mice

Psychoanalytic sociology and the traumas of history: Alexander Mitscherlich between the disciplines

This article examines the way aspects of recent history were excluded in key studies emerging from psychoanalytic social psychology of the mid-twentieth century. It draws on work by Erikson, Marcuse and Fromm, but focuses in particular on Alexander Mitscherlich. Mitscherlich, a social psychologist associated with the later Frankfurt school, was also the most important psychoanalytic figure in postwar Germany. This makes his work significant for tracing ways in which historical experience of the war and Nazism was filtered out of psychosocial narratives in this period, in favour of more structural analyses of the dynamics of social authority. Mitscherlich?s 1967 work The Inability to Mourn, co-authored with Margarete Mitscherlich, is often cited as the point at which the ?missing? historical experience flooded back into psychoanalytic accounts of society. I argue that this landmark publication doesn?t hail the shift towards the psychoanalysis of historical experience with which it is often associated. These more sociological writers of the mid-century were writing before the impact of several trends occurring in the 1980s-90s which decisively shifted psychoanalytic attention away from the investigation of social authority and towards a focus on historical trauma. Ultimately this is also a narrative about the transformations which occur when psychoanalysis moves across disciplines

Protein-protein interactions in the RPS4/RRS1 immune receptor complex

Plant NLR (Nucleotide-binding domain and Leucine-rich Repeat) immune receptor proteins are encoded by Resistance (R) genes and confer specific resistance to pathogen races that carry the corresponding recognized effectors. Some NLR proteins function in pairs, forming receptor complexes for the perception of specific effectors. We show here that the Arabidopsis RPS4 and RRS1 NLR proteins are both required to make an authentic immune complex. Over-expression of RPS4 in tobacco or in Arabidopsis results in constitutive defense activation; this phenotype is suppressed in the presence of RRS1. RRS1 protein co-immunoprecipitates (co-IPs) with itself in the presence or absence of RPS4, but in contrast, RPS4 does not associate with itself in the absence of RRS1. In the presence of RRS1, RPS4 associates with defense signaling regulator EDS1 solely in the nucleus, in contrast to the extra-nuclear location found in the absence of RRS1. The AvrRps4 effector does not disrupt RPS4-EDS1 association in the presence of RRS1. In the absence of RRS1, AvrRps4 interacts with EDS1, forming nucleocytoplasmic aggregates, the formation of which is disturbed by the co-expression of PAD4 but not by SAG101. These data indicate that the study of an immune receptor protein complex in the absence of all components can result in misleading inferences, and reveals an NLR complex that dynamically interacts with the immune regulators EDS1/PAD4 or EDS1/SAG101, and with effectors, during the process by which effector recognition is converted to defense activation

GOPred: GO Molecular Function Prediction by Combined Classifiers

Functional protein annotation is an important matter for in vivo and in silico biology. Several computational methods have been proposed that make use of a wide range of features such as motifs, domains, homology, structure and physicochemical properties. There is no single method that performs best in all functional classification problems because information obtained using any of these features depends on the function to be assigned to the protein. In this study, we portray a novel approach that combines different methods to better represent protein function. First, we formulated the function annotation problem as a classification problem defined on 300 different Gene Ontology (GO) terms from molecular function aspect. We presented a method to form positive and negative training examples while taking into account the directed acyclic graph (DAG) structure and evidence codes of GO. We applied three different methods and their combinations. Results show that combining different methods improves prediction accuracy in most cases. The proposed method, GOPred, is available as an online computational annotation tool (http://kinaz.fen.bilkent.edu.tr/gopred)