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Microbes play a critical role in regulating the size, composition, and turnover of dissolved organic matter (DOM), which is one of the largest pools of carbon in aquatic ecosystems. Global change may alter DOM-microbe associations with implications for biogeochemical cycles, although disentangling these complex interactions remains a major challenge. Here we develop a framework called Energy-Diversity-Trait integrative Analysis (EDTiA) to examine the associations between DOM and bacteria along temperature and nutrient gradients in a manipulative field experiment on mountainsides in contrasting subarctic and subtropical climates. In both study regions, the chemical composition of DOM correlated with bacterial communities, and was primarily controlled by nutrients and to a lesser degree by temperature. At a molecular-level, DOM-bacteria associations depended strongly on the molecular traits of DOM, with negative associations indicative of decomposition as molecules are more biolabile. Using bipartite networks, we further demonstrated that negative associations were more specialized than positive associations indicative of DOM production. Nutrient enrichment promoted specialization of positive associations, but decreased specialization of negative associations particularly at warmer temperatures in subtropical climate. These global change drivers influenced specialization of negative associations most strongly via molecular traits, while both molecular traits and bacterial diversity similarly affected positive associations. Together, our framework provides a quantitative approach to understand DOM-microbe associations and wider carbon cycling across scales under global change.

Increasing evidence suggests that olfactory impairment is associated with an increased risk of conversion from mild cognitive impairment MCI to Alzheimer's disease. This study was to explore how olfactory identification relates to white matter WM integrity, using diffusion tensor imaging DTI in individuals with amnestic MCI. DTI was performed from nineteen individuals with amnestic MCI mean age: 69.95±8.20 years. Olfactory identification was assessed using the Cross-Cultural Smell Identification Test CC-SIT, a widely used test for odor identification involving a scratch and sniff test of 12 micro-encapsulated odorants. Cross-sectional voxel-wise analyses of relationships between CC-SIT scores and DTI indices were performed using Tract-Based Spatial Statistics. Higher CC-SIT scores were associated with lower mean, axial and radial diffusivities in areas such as the body and splenium of corpus callosum, frontal WM lateral orbitofrontal, caudal middle frontal, precentral, left superior frontal, and right pars opercularis, right superior longitudinal fasciculus, anterior and superior corona radiata, and internal and external capsules, while CC-SIT scores were not significantly associated with fractional anisotropy across all MCI participants. In individuals with amnestic MCI, impaired olfactory identification is associated with alterations in WM integrity expressed as a lower diffusivities value. This cross-sectional preliminary study suggests that olfactory impairment contributes to WM microstructural alterations in individuals with amnestic MCI. © 2016 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 270-276, 2016

In article number 2004885, Young Min Song and co‐workers report a new way to address thermal issue caused in wearable optoelectronics in outdoor by introducing non‐metallic/flexible radiative cooler with sub ambient cooling of 6 °C in daytime. Under sunlight, the conventional wearable device exhibits an inaccurate tissue oxygen saturation (StO(2)) value of ≈67%, however, the thermally protected wearable device presents reliable StO(2) of ≈80%. [Image: see text]

For wearable electronics/optoelectronics, thermal management should be provided for accurate signal acquisition as well as thermal comfort. However, outdoor solar energy gain has restricted the efficiency of some wearable devices like oximeters. Herein, wireless/battery‐free and thermally regulated patch‐type tissue oximeter (PTO) with radiative cooling structures are presented, which can measure tissue oxygenation under sunlight in reliable manner and will benefit athlete training. To maximize the radiative cooling performance, a nano/microvoids polymer (NMVP) is introduced by combining two perforated polymers to both reduce sunlight absorption and maximize thermal radiation. The optimized NMVP exhibits sub‐ambient cooling of 6 °C in daytime under various conditions such as scattered/overcast clouds, high humidity, and clear weather. The NMVP‐integrated PTO enables maintaining temperature within ≈1 °C on the skin under sunlight relative to indoor measurement, whereas the normally used, black encapsulated PTO shows over 40 °C owing to solar absorption. The heated PTO exhibits an inaccurate tissue oxygen saturation (StO2) value of ≈67% compared with StO2 in a normal state (i.e., ≈80%). However, the thermally protected PTO presents reliable StO2 of ≈80%. This successful demonstration provides a feasible strategy of thermal management in wearable devices for outdoor applications., This article presents a radiative cooled wireless/battery‐free patch type tissue oximeter with nano/microvoids polymer (NMVP) for eliminating the thermal issue of optoelectronics. The NMVP integrated tissue oximeter serves a temperature within ≈1 °C on the skin under direct sunlight relative to indoor measurement, delivering reliable tissue oxygen saturation, unlike normally black encapsulated devices.

Electromagnetic fields (EMFs) can modulate cell proliferation, DNA replication, wound healing, cytokine expression, and the differentiation of mesenchymal stem cells (MSCs). Graphene, a 2D crystal of sp(2) -hybridized carbon atoms, has entered the spotlight in cell and tissue engineering research. However, a combination of graphene and EMFs has never been applied in tissue engineering. This study combines reduced graphene oxide (RGO) and pulsed EMFs (PEMFs) on the osteogenesis and neurogenesis of MSCs. First, the chemical properties of RGO are measured. After evaluation, the RGO is adsorbed onto glass, and its morphological and electrical properties are investigated. Next, an in vitro study is conducted using human alveolar bone marrow stem cells (hABMSCs). Their cell viability, cell adhesion, and extracellular matrix (ECM) formation are increased by RGO and PEMFs. The combination of RGO and PEMFs enhances osteogenic differentiation. Together, RGO and PEMFs enhance the neurogenic and adipogenic differentiation of hABMSCs. Moreover, in a DNA microarray analysis, the combination of RGO and PEMFs synergically increases ECM formation, membrane proteins, and metabolism. The combination of RGO and PEMFs is expected to be an efficient platform for stem cell and tissue engineering.

Recently developed classes of electronics for biomedical applications exploit substrates that offer low elastic modulus and high stretchability, to allow intimate, mechanically biocompatible integration with soft biological tissues. A challenge is that such substrates do not generally offer protection of the electronics from high peak strains that can occur upon large-scale deformation, thereby creating a potential for device failure. The results presented here establish a simple route to compliant substrates with strain-limiting mechanics based on approaches that complement those of recently described alternatives. Here, a thin film or mesh of a high modulus material transferred onto a prestrained compliant substrate transforms into wrinkled geometry upon release of the prestrain. The structure formed by this process offers a low elastic modulus at small strain due to the small effective stiffness of the wrinkled film or mesh; it has a high tangent modulus (e.g., >1000 times the elastic modulus) at large strain, as the wrinkles disappear and the film/mesh returns to a flat geometry. This bilinear stress–strain behavior has an extremely sharp transition point, defined by the magnitude of the prestrain. A theoretical model yields analytical expressions for the elastic and tangent moduli and the transition strain of the bilinear stress–strain relation, with quantitative correspondence to finite element analysis and experiments.

Optogenetics is an advanced neuroscience technique that enables the dissection of neural circuitry with high spatiotemporal precision. Recent advances in materials and microfabrication techniques have enabled minimally invasive and biocompatible optical neural probes, thereby facilitating in vivo optogenetic research. However, conventional fabrication techniques rely on cleanroom facilities, which are not easily accessible and are expensive to use, making the overall manufacturing process inconvenient and costly. Moreover, the inherent time-consuming nature of current fabrication procedures impede the rapid customization of neural probes in between in vivo studies. Here, we introduce a new technique stemming from 3D printing technology for the low-cost, mass production of rapidly customizable optogenetic neural probes. We detail the 3D printing production process, on-the-fly design versatility, and biocompatibility of 3D printed optogenetic probes as well as their functional capabilities for wireless in vivo optogenetics. Successful in vivo studies with 3D printed devices highlight the reliability of this easily accessible and flexible manufacturing approach that, with advances in printing technology, can foreshadow its widespread applications in low-cost bioelectronics in the future.

The invention provides systems and methods for tissue-mounted electronics and photonics. Devices of some embodiments of the invention implement high performance, and optionally flexible, device components having miniaturized formats in device architectures that minimize adverse physical effects to tissue and/or reduce interfacial stresses when mounted on tissue surfaces. In some embodiments, the invention provides complementary tissue mounting strategies providing for mechanically robust and/or long term integration of the present devices, for example, via mounting on tissue surfaces that are not subject to rapid growth or exfoliation processes such as the fingernail, toenail, tooth or earlobe. Devices of the invention are versatile and support a broad range of applications for sensing, actuating and communication including applications for near field communication, for example, for password authentication, electronic transactions and biometric sensing.

This paper presents materials and core/shell architectures that provide optimized mechanical properties in packages for stretchable electronic systems. Detailed experimental and theoretical studies quantitatively connect the geometries and elastic properties of the constituent materials to the overall mechanical responses of the integrated systems, with a focus on interfacial stresses, effective modulus, and maximum extent of elongation. Specific results include core/shell designs that lead to peak values of the shear and normal stresses on the skin that remain less than 10 kPa even for applied strains of up to 20%, thereby inducing minimal somatosensory perception of the device on the human skin. Additional, strain-limiting mesh structures embedded in the shell improve mechanical robustness by protecting the active components from strains that would otherwise exceed the fracture point. Demonstrations in precommercial stretchable electronic systems illustrate the utility of these concepts.

Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul 110-749,Republic of KoreaReceived 12 May 2014; revised 1 September 2014; accepted 10 October 2014Published online 00 Month 2014 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/jbm.b.33316Abstract: In recent years, cell chip-based platforms havebegun to show promise as a means of corroborating the find-ings of in vivo animal tests for cytotoxicity, and perhaps in thefuture partially replacing the need for such animal models. Incontrast to the conventional culture methods, micro- andnanofabrication techniques can be utilized to provide a set ofmechanostimulatory signals to the cells that mimic the contextof extracellular matrix (ECM) of the tissue in which a particularcell line resides. Here, we report periodic lateral topographicstriations, with a pitch ranging approximately from 200 to800 nm with an intention to mimic a common geometry offibrils in the ECM such as collagen or elastin, as a platform forinvestigating anticancer drug-induced cytotoxicity in stemcells. The ECM cues could facilitate perimeter, elongation, andgap junction formation of mesenchymal stem cells (MSCs),which eventually influenced the fate of cells in terms of deathand survival against the common chemotherapeutic agent cis-platin. Interestingly, the appropriate inhibition of gap junctionsof MSCs on the ECM mimicking substrates could prevent thecisplatin–induced cytotoxicity through the inhibition of thecisplatin-induced ‘death signal communication’ as comparedto that on the flat substrates. Our results imply that nanoscaletopography is an important consideration for chip-based cyto-toxicity assays, which uniquely enable the consideration andrational design of ECM-like topographic features, and further-more, that the natural topography of the ECM in the context ofstem cell niches may serve as an important indicator for che-motherapeutic agent sensitivity.

Epidermal electronics with advanced capabilities in near field communications (NFC) are presented. The systems include stretchable coils and thinned NFC chips on thin, low modulus stretchable adhesives, to allow seamless, conformal contact with the skin and simultaneous capabilities for wireless interfaces to any standard, NFC-enabled smartphone, even under extreme deformation and after/during normal daily activities.

Combination of optogenetics and pharmacology represents a unique approach to dissect neural circuitry with high specificity and versatility. However, conventional tools available to perform these experiments, such as optical fibers and metal cannula, are limited due to their tethered operation and lack of biomechanical compatibility. To address these issues, a miniaturized, battery-free, soft optofluidic system that can provide wireless drug delivery and optical stimulation for spatiotemporal control of the targeted neural circuit in freely behaving animals is reported. The device integrates microscale inorganic light-emitting diodes and microfluidic drug delivery systems with a tiny stretchable multichannel radiofrequency antenna, which not only eliminates the need for bulky batteries but also offers fully wireless, independent control of light and fluid delivery. This design enables a miniature (125 mm3 ), lightweight (220 mg), soft, and flexible platform, thus facilitating seamless implantation and operation in the body without causing disturbance of naturalistic behavior. The proof-of-principle experiments and analytical studies validate the feasibility and reliability of the fully implantable optofluidic systems for use in freely moving animals, demonstrating its potential for wireless in vivo pharmacology and optogenetics.

N-glycan structures released from miniature pig endothelial and islet cells were determined by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF), negative ion electrospray ionization (ESI) MS/MS and normal-phase high performance liquid chromatography (NP-HPLC) combined with exoglycosidase digestion. Totally, the identified structures were 181 N-glycans including 129 sialylated and 18 α-galactosylated glycans from pig endothelial cells and 80 N-glycans including 41 sialylated and one α-galactosylated glycans from pig islet cells. The quantity of the α-galactosylated glycans from pig islet cells was certainly neglectable compared to pig endothelial cells. A number of NeuGc-terminated N-glycans (80 from pig endothelial cells and 13 from pig islet cells) are newly detected by our mass spectrometric strategies. The detailed structural information will be a matter of great interest in organ or cell xenotransplantation using α 1,3-galactosyltransferase gene-knockout (GalT-KO) pig. Copyright © 2009 John Wiley & Sons, Ltd.

We present a method of reducing the size of antennas that is based on composite right/left-handed (CRLH) transmission lines (TL) which use a magneto-dielectric material (MDM). The CRLH-TL antenna consists of two mushroom structures, each composed of a metal patch connected to the ground plane by a via. To achieve high permeability in the antenna, an MDM is constructed by integrating split ring resonators into ordinary dielectric material. Antennas with and without MDM were fabricated and measured. Inserting the MDM decreased the antenna's resonant frequencies by 10.8% at the −1st order mode and by 11.3% at the zeroth-order mode. At the zeroth-order mode, the antenna resonated at 1.88 GHz with a bandwidth of 0.48% and had a monopolar radiation pattern, with gain of 0.534 dBi and efficiency of 51.7%. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1994–1997, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24490

In this article, embedded capacitor pastes (ECPs) with various BaTiO3 (BTO) powder contents were formulated and screen-printed on PCBs to fabricate capacitors. The material properties of the ECPs that included their rheology, curing behavior, and dielectric constant were investigated. Embedded capacitors were fabricated for reliability tests related to the thermal cycling and high temperature and humidity potential of optimized ECPs. Additionally, changes in the dielectric properties were discussed. ECPs were formulated with various powder contents from 0 to 70 vol %. ECP resin was cured at temperatures ranging from 130 to 220°C. All ECPs had the viscosities below 30 Pa · s at a shear rate of 100 s−1 to be easily screen-printable. The dielectric constant of the cured ECPs increased to 60 at 70 vol %, and the dielectric loss was approximately 0.023 for all ECPs regardless of BTO volume content. For the reliability test, ECPs with 50, 60, and 70 vol % BTO powder contents were selected and embedded capacitors were fabricated. After a thermal cycling test with a temperature range from −55 to 125°C for 1000 cycles, capacitance decreased by approximately 5 ∼ 10%, but the dielectric loss did not change. After a 85°C/85RH% test for 1000 h, the capacitance and dielectric loss increased by nearly 20%. Cyanoresin (CRS) was used to form the high dielectric polymer/ceramic composite material. The newly formulated resin system had a dielectric constant that is double that of a conventional epoxy resin system. Additionally, the dielectric constant of the polymer/ceramic composite material increased 50% at 50 vol %. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Modelling from images is a cost-effective means of obtaining virtual cultural heritage models. These models can be effectively constructed from classical Structure from Motion algorithm. However, it's too difficult to reconstruct whole scenes using SFM method since general oriental historic sites contain a very complex shapes and brilliant colours. To overcome this difficulty, the current paper proposes a new reconstruction method based on a moving planar mirror. We devise the mirror posture instead of scene itself as a cue for reconstructing the geometry. That implies that the geometric cues are inserted into the scene by compulsion. With this method, we can obtain the geometrical details regardless of the scene complexity. For this purpose, we first capture image sequences through the moving mirror containing the interested scene, and then calibrate the camera through the mirror's posture. Since the calibration results are still inaccurate due to the detection error, the camera pose is revised using frame-correspondence of the corner points that are easily obtained using the initial camera posture. Finally, 3D information is computed from a set of calibrated image sequences. We validate our approach with a set of experiments on some cultural heritage objects. Copyright © 2004 John Wiley & Sons, Ltd.

Immune stimulants, such as the bacterial endotoxin, lipopolysaccharide (LPS), the human immunodeficiency virus-1 coat protein gp120, or beta-amyloid peptides, lead to glial activation and production of various immune mediators, such as nitric oxide (NO) and proinflammatory cytokines in the brain. These mediators appear to contribute to neuronal cell death in neurodegenerative diseases. However, the signaling pathways, which mediate the neurotoxic effect by the endotoxin, are not understood. The purpose of this study was to determine the role of mitogen-activated protein kinase (MAPK) in LPS-induced neurodegeneration using mesencephalic dopaminergic neuron/glia cultures. We have found that the p38 MAPK is important in LPS-induced death of mesencephalic neurons in rat neuron-glia mixed cultures. Upon treatment with 10 ng/ml LPS, the number of dopaminergic neurons decreased by 80% within 48 h, preceded by a significant production of NO by glia. Neuroprotection by selective inhibition of p38 MAPK activity paralleled a decrease in LPS-induced inducible nitric oxide synthase (iNOS) expression. These events were significantly reduced by the selective p38 MAPK inhibitor, SB202190, but not by the inactive analogue SB202474. Inhibition of iNOS activity and NO production by treatment with GW274150 was also neuroprotective. Although the p38 MAPK inhibitor afforded significant neuroprotection from LPS toxicity in the neuron-glia mixed culture, it failed to protect dopaminergic neurons from 6-hydroxy-dopamine-induced toxicity, which acts directly on dopaminergic neurons by inducing hydroxyl radical formation from the mitochondria. The results suggest that p38 MAPK in glia plays a significant role in the LPS-induced death of mesencephalic neurons through induction of nitric oxide synthase and resulting NO production.

Co-infection with hepatitis B virus (HBV) and hepatitis C virus (HCV) is common and is associated with a more severe liver disease and increased frequency in the development of hepatocellular carcinoma (HCC). Here, we demonstrated that HBV X protein (HBx) and HCV core protein additively repress the universal cyclin-dependent kinase inhibitor p21 gene at the transcription level. The transforming growth factor-β responsive element and Sp1 site of the p21 promoter were responsible for the effect of HCV core and HBx, respectively. Furthermore, cell growth was additively stimulated by them, suggesting that additive repression of the p21 might be important to understand the cooperative development of HCC by HBV and HCV.

The CIP (Cubic-Interpolated Pseudoparticle/Propagation) method can treat all of the phase states (solid, liquid, and gas) together and can trace a sharp interface without changing of the grid or topology. The material interface can be captured almost by one grid because the numerical diffusion can be decreased by CIP. For this advantage, if we are able to adopt CIP on a general FVM code, we can easily treat a variety of phase change problems in which the phase interfaces need to be traced. In this paper, an unsteady close-contact melting phenomenon is analyzed by combining CIP with the enthalpy method. The film growth rate and the phase interface's moving rate are compared with the analytic solution and the acceptability and usefulness of this method are evaluated. The obtained results agree quite well with the published analytic solutions. © 2001 Scripta Technica, Heat Trans Asian Res, 30(6): 463–472, 2001