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The United States is facing a surge in the aging population, which will increase the demand for services and supports that allow older adults to age independently. This study assessed the size and value of the volunteer labor force in two home- and community-based programs funded under the Older Americans Act (OAA). Using publicly available program data for fiscal years 2015-2019, we calculated the annual contribution of volunteers, based on the total number of volunteer hours and share of labor effort, and estimated the economic value of volunteers in these OAA programs. In fiscal year 2019, volunteers contributed a total value of $1.7 billion in the OAA Title III program and $14.0 million in the Title VII long-term care ombudsman program. These results highlight the value of volunteers in OAA programs and the need for policies to support volunteers in the aging services network.

In robotics and computer vision communities, extensive studies have been widely conducted regarding surveillance tasks, including human detection, tracking, and motion recognition with a camera. Additionally, deep learning algorithms are widely utilized in the aforementioned tasks as in other computer vision tasks. Existing public datasets are insufficient to develop learning-based methods that handle various surveillance for outdoor and extreme situations such as harsh weather and low illuminance conditions. Therefore, we introduce a new large-scale outdoor surveillance dataset named eXtremely large-scale Multi-modAl Sensor dataset (X-MAS) containing more than 500,000 image pairs and the first-person view data annotated by well-trained annotators. Moreover, a single pair contains multi-modal data (e.g. an IR image, an RGB image, a thermal image, a depth image, and a LiDAR scan). This is the first large-scale first-person view outdoor multi-modal dataset focusing on surveillance tasks to the best of our knowledge. We present an overview of the proposed dataset with statistics and present methods of exploiting our dataset with deep learning-based algorithms. The latest information on the dataset and our study are available at https://github.com/lge-robot-navi, and the dataset will be available for download through a server., 8 pages, 13 figures, IEEE Robotics and Automation Letters

The aesthetic aspect of automobiles continuously plays an important role in attracting consumer’s purchasing intention. In accordance with the needs of customers, automobile industries try to evaluate and amend a surface defect of their products. This research identifies manufacturing variables that have considerable correlation with surface defects in the exterior panel of large commercial vehicle and investigates the optimal condition of them to minimize the flaws. Multiple manufacturing processes that the exterior panel undergoes are modeled based on the multi-physics approach. From the computational analysis, the influences of the manufacturing variables on the surface defect are systematically analyzed to define effective parameters. An optimization regarding the influential variables is conducted and presents the optimized manufacturing processes for the high exterior quality of commercial vehicle.

Photovoltaic devices that convert solar energy into electrical energy are a promising solution to resolve environmental problems the world is facing today. Among the various photovoltaic system, dye-sensitized solar cells (DSSCs) has been regarded as a new generation of the photovoltaic device due to the low cost and simple fabrication process. However, the current design of DSSCs shows insufficient conversion efficiency. To solve this problem, we increase the optical path length by trapping the incident light using a diffraction grating with high reflectance. We numerically investigate the effect of geometric parameters on the reflectance of diffraction gratings in DSSC system. Based on the simulation results, we propose an optimized geometry of diffraction grating that reflects the outgoing light and traps the incident light. The optimized geometry of the diffraction grating increase in the reflectance about 80% when it is compared to that without the diffraction grating.

A rapid, precise method for identifying waterborne pathogens is critically needed for effective disinfection and better treatment. However, conventional methods, such as culture-based counting, generally suffer from slow detection times and low sensitivities. Here, we developed a rapid detection method for tracing waterborne pathogens by an innovative optofluidic platform, a plasmonic bacteria on a nanoporous mirror, that allows effective hydrodynamic cell trapping, enrichment of pathogens, and optical signal amplifications. We designed and simulated the integrated optofluidic platform to maximize the enrichment of the bacteria and to align bacteria on the nanopores and plasmonic mirror via hydrodynamic cell trapping. Gold nanoparticles are self-assembled to form antenna arrays on the surface of bacteria, such as Escherichia coli and Pseudomonas aeruginosa, by replacing citrate with hydroxylamine hydrochloride in order to amplify the signal of the plasmonic optical array. Owing to the synergistic contributions of focused light via the nanopore geometry, self-assembled nanoplasmonic optical antennas on the surface of bacteria, and plasmonic mirror, we obtain a sensitivity of detecting E. coli as low as 102 cells/ml via surface-enhanced Raman spectroscopy. We believe that our label-free strategy via an integrated optofluidic platform will pave the way for the rapid, precise identification of various pathogens., Nanoparticles: making it easier to detect waterborne pathogens A novel method using nanotechnology to rapidly identify bacteria in water samples has been developed by scientists in the Republic of Korea and the US. Waterborne pathogens kill millions of people each year, but detection methods can be time-consuming, lack sensitivity, and only work with small samples. Taewook Kang at Sogang University, Seoul, and co-workers fabricated a gold-coated mirror filled with nano-sized holes smaller than an individual bacterium, and added especially modified gold nanoparticles to their water samples. The nanoparticles stuck onto the surface of bacteria, such as Escherichia coli, which in turn made the bacteria likely to cluster around the mirror’s pores. These measures greatly enhanced the interactions between the bacteria and light, so that even very low cell concentrations could be detected using spectroscopy, and different species of bacteria could be distinguished.

The pentamode structure is a type of mechanical metamaterial that displays dramatically different bulk and shear modulus responses. In this study, a face-centered cubic (FCC) polymeric microstructure was fabricated by using SU8 negative-type photoresists and multibeam interference exposure. Isotropic plasma etching is used to control the solid-volume fraction; for the first time, we obtained a structure with the minimum solid-volume fraction as low as 15% that still exhibited high structural integrity. Using this method, we reduced the width of atom-to-atom connections by up to 40 nm. We characterize the effect of the connection area on the anisotropy of the mechanical properties using simulations. Nanoindentation measurements were also conducted to evaluate the energy dissipation by varying the connection area. The Young's/shear modulus ratio is 5 times higher for the etched microstructure than that of the bulk SU8 materials. The use of interference lithography may enable the properties of microscale materials to be engineered for various applications, such as MEMS.

Controlled assembly of colloidal nanoparticles onto solid substrates generally needs to overcome their thermal diffusion in water. For this purpose, several techniques that are based on chemical bonding, capillary interactions with substrate patterning, optical force, and optofluidic heating of light-absorbing substrates are proposed. However, the direct assembly of colloidal nanoparticles on generic substrates without chemical linkers and substrate patterning still remains challenging. Here, photothermal convection lithography is proposed, which allows the rapid placement of colloidal nanoparticles onto the surface of diverse solid substrates. It is based on local photothermal heating of colloidal nanoparticles by resonant light focusing without substrate heating, which induces convective flow. The convective flow, then, forces the colloidal nanoparticles to assemble at the illumination point of light. The size of the assembly is increased by either increasing the light intensity or illumination time. It is shown that three types of colloidal gold nanoparticles with different shapes (rod, star, and sphere) can be uniformly assembled by the proposed method. Each assembly with a diameter of tens of micrometers can be completed within a minute and its patterned arrays can also be achieved rapidly.

Here, we propose an environmentally benign removal technique for heavy metal ions based on selective and spontaneous transfer to oleic acid. The ions can be removed via (1) the selective and rapid complexation with the carboxylic end of oleic acid at an oleic acid/water interface, and (2) the diffusion of such complex into the oleic acid layer. A wide variety of heavy metal ions such as Cu2+, Pb2+, Zn2+, and Ni2+ can be selectively removed over K+ and Na+. For example, the concentration of Cu2+ is reduced to below 1.3 ppm within 24 h, which corresponds to the level of Cu2+ permitted by the Environmental Protection Agency. The addition of ethylenediamine ligand to the metal ion solutions is also shown to enhance the phase transfer. The removal efficiency is increased by up to 6 times when compared with that in the absence of the ligand and follows the order, Cu2+ (99%) > Pb2+ (96%) > Zn2+ (95%) > Ni2+ (65%). Moreover, the removal time can be shortened from 24 h to 1 h. The effect of an emulsion induced by a mechanical agitation on the removal of heavy metal ion is also studied.

The mechanical behavior of a Zircaloy-4 sheet as induced by a pulsed laser was studied with an accurately developed computational process that was validated with experiments. A modified Gaussian model of the heat source and the use of experimentally obtained thermal and mechanical properties of Zircaloy-4 in the computational process provided reliable simulation results of the phase transition and mechanical deformation of Zircaloy-4. A parametric study of the pulsed laser welding conditions of Zircaloy-4 was undertaken using the developed computational process. The analyzed parameters were the laser power, pulse duration, and pulse frequency. The simulation results revealed that the deformation was significantly dependent on the geometry of the molten zone and the heat-affected zone, which can be designed by the analyzed laser parameters.

Pyrolysis is recently proposed as an efficient fabrication technique of micro/nanoscale carbon structures. In order to understand the morphological evolution in pyrolysis and design the final shape of carbon structure, this study proposes a comprehensive model that incorporates the essential mechanisms of pyrolysis based on the phase field framework. Computational analysis with the developed model provides information about the effect of interface energy and kinetic rate on the morphological evolution in pyrolysis.

Programmable liposomes are designed to selectively produce various liposome-nanoparticle hybrids., Hybrid liposome/metal nanoparticles are promising candidate materials for biomedical applications. However, the poor selectivity and low yield of the desired hybrid during synthesis pose a challenge. We designed a programmable liposome by selective encoding of a reducing agent, which allows self-crystallization of metal nanoparticles within the liposome to produce stable liposome/metal nanoparticles alone. We synthesized seven types of liposome/monometallic and more complex liposome/bimetallic hybrids. The resulting nanoparticles are tunable in size and metal composition, and their surface plasmon resonance bands are controllable in visible and near infrared. Owing to outer lipid bilayer, our liposome/Au nanoparticle shows better colloidal stability in biologically relevant solutions as well as higher endocytosis efficiency than gold nanoparticles without the liposome. We used this hybrid in intracellular imaging of living cells via surface-enhanced Raman spectroscopy, taking advantage of its improved physicochemical properties. We believe that our method greatly increases the utility of metal nanoparticles in in vivo applications.

This study describes the electrodeposition of thin films with a two-step approach that is based on the initial modification of polycrystalline Au electrode with a selenium overlayer followed by a cathodic stripping of the layer as in a 1 M lactic acid electrolyte containing ions. For this two-step approach to be effective, the reduction potential should be shifted to more negative potentials passed potentials for the reduction of Se to . This was accomplished by the complexation of ions with lactic acid. The resultant films were characterized by linear sweep voltammetry combined with electrochemical quartz crystal microgravimetry, UV-vis absorption spectrometry and Raman spectroscopy. Photoelectrochemical experiments revealed that synthesized thus, behaved as a p-type semiconductor.

In this communication a hybrid electrosynthetic approach for preparingAu/ZnOnanocompositeispresentedcombininginitialelectrodeposition of ZnO nanorod arrays followed by subsequent galvanic replacement of the co-deposited Zn with Au to yield the targeted nanoarchitecture. Among the many oxide semiconductor candidates for solar photoelectrochemical applications, zinc oxide (ZnO) has received much attention because of its high stability, high electron mobility, and low toxicity in neutral and alkaline media. 1‐3 However, thelargebandgap(Eg =∼ 3.4eV)ofthismaterialisamajordrawback, whichmakesZnOonlyrespondtowavelengthsintheUVregion.Considering that the UV component comprises less than ∼5% of the solar spectrum, semiconductors with smaller band gaps or alternatively, metal/semiconductor composite materials are desirable.

Smart city and innovative building strategies are becoming increasingly more necessary because advancing a sustainable building system is regarded as a promising solution to overcome the depleting water and energy. However, current sustainable building systems mainly focus on energy saving and miss a holistic integration of water regeneration and energy generation. Here, we present a theoretical study of a solar optics-based active panel (SOAP) that enables both solar energy storage and photothermal disinfection of greywater simultaneously. Solar collector efficiency of energy storage and disinfection rate of greywater have been investigated. Due to the light focusing by microlens, the solar collector efficiency is enhanced from 25% to 65%, compared to that without the microlens. The simulation of greywater sterilization shows that 100% disinfection can be accomplished by our SOAP for different types of bacteria including Escherichia coli. Numerical simulation reveals that our SOAP as a lab-on-a-wall system can resolve the water and energy problem in future sustainable building systems.

Mechanical metamaterials that are engineered with sub-unit structures present unusual mechanical properties depending on the loading direction. Although they show promise, their practical utility has so far been somewhat limited because, to the best of our knowledge, no study about the potential of mechanical metamaterials made from sophisticatedly tailored sub-unit structures has been made. Here, we present a mechanical metamaterial whose mechanical properties can be systematically designed without changing its chemical composition or weight. We study the mechanical properties of triply periodic bicontinuous structures whose detailed sub-unit structure can be precisely fabricated using various sub-micron fabrication methods. Simulation results show that the effective wave velocity of the structures along with different directions can be designed to introduce the anisotropy of stiffness by changing a volume fraction and aspect ratio. The ratio of Young’s modulus to shear modulus can be increased by up to at least 100, which is a 3500% increase over that of isotropic material (2.8, acrylonitrile butadiene styrene). Furthermore, Poisson’s ratio of the constituent material changes the ratio while Young’s modulus does not influence it. This study presents the promising potential of mechanical metamaterials for versatile industrial and biomedical applications.

Since the invention of the atomic force microscope (AFM) three decades ago, there have been numerous advances in its measurement capabilities. Curiously, throughout these developments, the fundamental nature of the force-sensing probe—the key actuating element—has remained largely unchanged. It is produced by long-established microfabrication etching strategies and typically composed of silicon-based materials. Here, we report a new class of photopolymerizable hydrogel nano-probes that are produced by bottom-up fabrication with compressible replica moulding. The hydrogel probes demonstrate excellent capabilities for AFM imaging and force measurement applications while enabling programmable, multifunctional capabilities based on compositionally adjustable mechanical properties and facile encapsulation of various nanomaterials. Taken together, the simple, fast and affordable manufacturing route and multifunctional capabilities of hydrogel AFM nano-probes highlight the potential of soft matter mechanical transducers in nanotechnology applications. The fabrication scheme can also be readily utilized to prepare hydrogel cantilevers, including in parallel arrays, for nanomechanical sensor devices., Atomic force microscopy typically employs hard tips to map the surface topology of a sample, with sub-nanometre resolution. Here, the authors instead develop softer hydrogel probes, which show potential for multifunctional measurement capabilities beyond that of conventional systems.

This study focuses on the preparation of CdSe/ZnO composite by combining three techniques, namely, electrodeposition, galvanic displacement, and photocathodic deposition. Thus ZnO nanowire array was first electrodeposited on Sn-doped indium oxide (ITO) or polycrystalline Au electrode; then, the metallic zinc codeposited with ZnO was galvanically replaced with Se from a Se4+ containing aqueous solution, which resulted in a Se/ZnO composite nanowire array. Finally, the Se component in Se/ZnO was photoelectrochemically reduced to Se2– by irradiation. The Se species reacted with Cd2+ in the electrolyte phase to produce CdSe/ZnO composite in situ. The deposition details were elucidated in situ by a combination of stripping voltammetry and electrochemical quartz crystal microgravimetry. The composite sample was subsequently characterized by scanning electron microscopy, X-ray powder diffraction, energy-dispersive X-ray analyses, and photoelectrochemical (PEC) measurements. The PEC experiments revealed that the ...

during stripping analysis of Te(IV) or Se(IV). Therefore in this study, the conventional HgFE was also deployed to investigate whether alloy formation is a general phenomenon (like in the BiFE instance above) or not. Finally, comparative aspects of Te determination at BiFE and HgFE will be briefly discussed.

Telemetry link requires high data rate to transmit the multimedia data for lunar explorations in space communications. In this paper, we analyze a data rate with the modulation and channel coding schemes based on Consultative Committee for Space Data Systems (CCSDS) in S, X, Ku and Ka bands, respectively. Then, we suggests modulation and channel coding schemes to meet the link margins and have a maximum data rate for lunar explorations in telemetry links.