The IKEA effect in collective problem‐solving: When individuals prioritize their own solutions

To improve problem‐solving performance, individuals can rely on social learning. This approach is constrained by an individual's social network, which influences the efficiency of the problem‐solving process. To date, research disagrees on what kind of network structure is preferable, providing support for efficient network structures, as well as for inefficient networks. However, studies implicitly assume that solvers always imitate superior solutions, an assumption that lacks empirical grounding. We propose a simple derivation of an existing simulation framework by incorporating a known cognitive bias (‘IKEA effect’), whereby individuals are assumed to prioritize individual information. This effect allows inefficiencies to be embodied at the individual microlevel, reducing the need for inefficiencies at the structural macrolevel. Simulation results explain discrepancies in previous results, illustrating how more realistic microlevel assumptions substantially impact macrolevel outcomes.     

Employing Interfaces with Metavalently Bonded Materials for Phonon Scattering and Control of the Thermal Conductivity in TAGS‐x Thermoelectric Materials

The thermoelectric compound (GeTe)_x(AgSbTe₂)_1?x, in short (TAGS‐x), is investigated with a focus on two stoichiometries, i.e., TAGS‐50 and TAGS‐85. TAGS‐85 is currently one of the most studied thermoelectric materials with great potential for thermoelectric applications. Yet, surprisingly, the lowest thermal conductivity is measured for TAGS‐50, instead of TAGS‐85. To explain this unexpected observation, atom probe tomography (APT) measurements are conducted on both samples, revealing clusters of various compositions and sizes. The most important role is attributed to Ag₂Te nanoprecipitates (NPs) found in TAGS‐50. In contrast to the Ag₂Te NPs, the matrix reveals an unconventional bond breaking mechanism. More specifically, a high probability of multiple events (PME) of ≈60% is observed for the matrix by APT. Surprisingly, the PME value decreases abruptly to ≈20–30% for the Ag₂Te NPs. These differences can be attributed to differences in chemical bonding. The precipitates' PME value is indicative of normal bonding, i.e., covalent bonding with normal optical modes, while materials with this unconventional bond breaking found in the matrix are characterized by metavalent bonding. This implies that the interface between the metavalently bonded matrix and covalently bonded Ag₂Te NP is partly responsible for the reduced thermal conductivity in TAGS‐50.     

Synthesis and characterization of polyvinyl alcohol/cellulose cryogels and their testing as carriers for a bioactive component

Novel physically cross-linked cryogels containing polyvinyl alcohol (PVA) and various amounts of microcrystalline cellulose were obtained by freezing/thawing technique. The main goal of this study was to improve the properties and the performances of the pure PVA cryogels. The morphological aspects of the cryogels were studied by scanning electron microscopy (SEM). The Fourier transform infrared spectroscopy (FT-IR) was used to reveal the presence of the interactions between the two polymers. Changes in crystallinity of the samples were confirmed by X-ray diffraction (XRD) and by FT-IR spectroscopy. The modification of the thermal behavior induced by cellulose was studied by thermogravimetry. Rheological analysis revealed higher values of storage modulus (G′) for the cryogels containing higher amounts of cellulose. The degree and rate of swelling were controlled by the presence of the natural polymer in the network. The potential application as bioactive compound carriers was tested, using vanillin as an active agent.     

Black Hole and Sink Hole Attack Detection in Wireless Body Area Networks

In Wireless Body Area Networks (WBANs) with respect to health care, sensors are positioned inside the body of an individual to transfer sensed data to a central station periodically. The great challenges posed to healthcare WBANs are the black hole and sink hole attacks. Data from deployed sensor nodes are attracted by sink hole or black hole nodes while grabbing the shortest path. Identifying this issue is quite a challenging task as a small variation in medicine intake may result in a severe illness. This work proposes a hybrid detection framework for attacks by applying a Proportional Coinciding Score (PCS) and an MK-Means algorithm, which is a well-known machine learning technique used to raise attack detection accuracy and decrease computational difficulties while giving treatments for heartache and respiratory issues. First, the gathered training data feature count is reduced through data pre-processing in the PCS. Second, the pre-processed features are sent to the MK-Means algorithm for training the data and promoting classification. Third, certain attack detection measures given by the intrusion detection system, such as the number of data packages trans-received, are identified by the MK-Means algorithm. This study demonstrates that the MK-Means framework yields a high detection accuracy with a low packet loss rate, low communication overhead, and reduced end-to-end delay in the network and improves the accuracy of biomedical data.     

Unique Bond Breaking in Crystalline Phase Change Materials and the Quest for Metavalent Bonding

Laser‐assisted field evaporation is studied in a large number of compounds, including amorphous and crystalline phase change materials employing atom probe tomography. This study reveals significant differences in field evaporation between amorphous and crystalline phase change materials. High probabilities for multiple events with more than a single ion detected per laser pulse are only found for crystalline phase change materials. The specifics of this unusual field evaporation are unlike any other mechanism shown previously to lead to high probabilities of multiple events. On the contrary, amorphous phase change materials as well as other covalently bonded compounds and metals possess much lower probabilities for multiple events. Hence, laser‐assisted field evaporation in amorphous and crystalline phase change materials reveals striking differences in bond rupture. This is indicative for pronounced differences in bonding. These findings imply that the bonding mechanism in crystalline phase change materials differs substantially from conventional bonding mechanisms such as metallic, ionic, and covalent bonding. Instead, the data reported here confirm a recently developed conjecture, namely that metavalent bonding is a novel bonding mechanism besides those mentioned previously.     

Bidirectional imaging and modeling of skin texture

In this paper, we present a method of skin imaging called bidirectional imaging that captures significantly more properties of appearance than standard imaging. The observed structure of the skin's surface is greatly dependent on the angle of incident illumination and the angle of observation. Specific protocols to achieve bidirectional imaging are presented and used to create the Rutgers Skin Texture Database (clinical component). This image database is the first of its kind in the dermatology community. Skin images of several disorders under multiple controlled illumination and viewing directions are provided publicly for research and educational use. Using this skin texture database, we employ computational surface modeling to perform automated skin texture classification. The classification experiments demonstrate the usefulness of the modeling and measurement methods.     

Synthesis and characterization of new aromatic polyesters and poly(ester-imide)s containing phosphorous cyclic bulky groups

New phosphorous-containing polyesters were prepared by polycondensation of 2-(6-oxido-6H-dibenz<c,e><1,2>oxaphosphorin-6-yl)-1,4-naphthalene diol, 1, with different aromatic dicarboxylic acids using a SOCl₂/pyridine condensing agent. Two poly(ester-imide)s were prepared by polycondensation in solution at high temperature of the same aromatic bisphenol 1, with diacid chlorides containing preformed imide rings. The most of the polymers were easily soluble in polar organic solvents such as N-methylpyrrolidone, N,N-dimethylformamide and chloroform. They showed high thermal stability, the decomposition temperature being in the range of 330-442 °C and glass transition in the temperature range of 193-226 °C. One of these polymers exhibited thermotropic liquid crystalline behavior. Due to the presence of phosphorus the polymers gave high char yield in termogravimetric analysis, hence good flame retardant properties.     

Neurotransmitters—Key Factors in Neurological and Neurodegenerative Disorders of the Central Nervous System

Neurotransmitters are molecules that amplify, transmit, and convert signals in cells, having an essential role in information transmission throughout the nervous system. Hundreds of such chemicals have been discovered in the last century, continuing to be identified and studied concerning their action on brain health. These substances have been observed to influence numerous functions, including emotions, thoughts, memories, learning, and movements. Thus, disturbances in neurotransmitters’ homeostasis started being correlated with a plethora of neurological and neurodegenerative disorders. In this respect, the present paper aims to describe the most important neurotransmitters, broadly classified into canonical (e.g., amino acids, monoamines, acetylcholine, purines, soluble gases, neuropeptides) and noncanonical neurotransmitters (e.g., exosomes, steroids, D-aspartic acid), and explain their link with some of the most relevant neurological conditions. Moreover, a brief overview of the recently developed neurotransmitters’ detection methods is offered, followed by several considerations on the modulation of these substances towards restoring homeostasis.