Inside cells, complex metabolic reactions are distributed across the modular compartments of organelles. Reactions in organelles have been recapitulated in vitro by reconstituting functional protein machineries into membrane systems. However, maintaining and controlling these reactions is challenging. Here we designed, built, and tested a switchable, light-harvesting organelle that provides both a sustainable energy source and a means of directing intravesicular reactions. An ATP (ATP) synthase and two photoconverters (plant-derived photosystem II and bacteria-derived proteorhodopsin) enable ATP synthesis. Independent optical activation of the two photoconverters allows dynamic control of ATP synthesis: red light facilitates and green light impedes ATP synthesis. We encapsulated the photosynthetic organelles in a giant vesicle to form a protocellular system and demonstrated optical control of two ATP-dependent reactions, carbon fixation and actin polymerization, with the latter altering outer vesicle morphology. Switchable photosynthetic organelles may enable the development of biomimetic vesicle systems with regulatory networks that exhibit homeostasis and complex cellular behaviors.
Poly-dimethylsiloxane (PDMS) fi lms with 2D periodic inverted moth-eye nanopatterns on one surface are implemented as antirefl ection (AR) layers on a glass substrate for effi cient light capture in encapsulated organic solar cells (OSCs). The inverted moth-eye nanopatterned PDMS (IMN PDMS) fi lms are fabricated by a soft imprint lithographic method using conical subwavelength grating patterns formed by laser interference lithography/ dry etching. Their optical characteristics, together with theoretical analysis using rigorous coupled-wave analysis simulation, and wetting behaviors are investigated. For a period of 380 nm, IMN PDMS fi lms laminated on glass substrates exhibit a hydrophobic surface with a water contact angle ( θ CA ) of ≈120° and solar weighted transmittance (SWT) of ≈94.2%, both signifi cantly higher than those ( θ CA ≈ 36° and SWT ≈ 90.3%) of bare glass substrates. By employing IMN PDMS fi lms with a period of 380 nm on glass substrates for OSCs, an enhanced power conversion effi ciency (PCE) of 6.19% is obtained mainly due to the increased short-circuit current density ( J sc ) of 19.74 mA cm −2 compared to the OSCs with the bare glass substrates (PCE = 5.16% and J sc = 17.25 mA cm −2 ). For the OSCs, the device stability is also studied.
The purpose of this article is to 1) address a paradigm shift taking place in the field of substance abuse prevention directed for youth and 2) to introduce an innovative approach to substance abuse and other problem behavior prevention that reflects this shift in prevention paradigm. The new path introduced is youth development and empowerment (YD&E) approach. In order to establish a conceptual foundation for this approach, this article 3) reviews the theoretical advances made in the field of substance abuse prevention during the last three decades. This is followed by a conceptualization of the processes of implementing the YD&E program by 4) specifying the mechanism used for the empowering processes and by 5) identifying the structural components of the youth empowerment model that serve the empowering processes. It is hoped that this article serves as a conduit for an improved approach to adolescent substance abuse prevention and youth development that goes beyond, rather than against, the traditional risk-factor approach. In this new approach, youths are viewed as assets and resources to our community rather than social problems or community liabilities. The organizing concept of this new paradigm is: social, economic, and public opportunity denied to youth is equal to social problems imposed on youth by adults.
This paper reports a lens-integrated liquid crystal display (LCD)-based optoelectronic tweezers (OET) system for interactive manipulation of polystyrene microspheres and blood cells by optically induced dielectrophoretic force. When a dynamic image pattern is projected into a specific area of a photoconductive layer in an OET, virtual electrodes are generated by spatially resolved illumination of the photoconductive layer, resulting in dielectrophoresis of microparticles suspended in the liquid layer under nonuniform electric field. In this study, the simple-structured OET system has been easily constructed with an OET device, an LCD and a condenser lens integrated in a conventional microscope. By using a condenser lens, both stronger dielectrophoretic forces and higher virtual electrode resolution than previously reported lens-less LCD-based OET platform are obtained. The effects of blurred LCD image and liquid chamber height on the performances of optoelectronic particle manipulation are investigated by measuring the bead velocities according to their sizes. An interactive control program for OET-based microparticle manipulation is also developed by Flash language. The integrated system is successfully applied to the parallel and interactive manipulation of red and white blood cells. Due to its simple structures, cheap manufacturing costs, and high performances, this new LCD-based OET platform may be a widely usable integrated system for optoelectronic manipulation of microparticles including living cells.
Poly(3-hexylthiophene) (P3HT) films were patterned by a soft lithography technique using a nanopatterned polydimethylsiloxane (PDMS) mold to generate one-dimensional (1D) grating and two-dimensional (2D) crossed line pillar patterns. The redox currents (i(p)) were significantly increased due to the facilitated diffusion of ClO4(-) counterions associated with redox processes at the P3HT electrode as analyzing cyclic voltammetry (CV) was performed at different scan rates (ν). It was found that the diffusion coefficient (D(f), cm(2) s(-1)) for ion diffusion in the patterned electrode was much larger than that of the pristine P3HT electrode. Furthermore, the value of D(f) in the 2D electrode was three times higher than that in a pristine film. As a result of such facilitated charge transport, the electrochromic (EC) properties of the patterned P3HT electrode were greatly enhanced and dependent on the dimension of the pattern. Thus, the electrochromic efficiency (E(e)), including the coloration (E(c)) and bleaching efficiencies (E(b)), was higher as the dimension of the pattern was increased; E(e) was maximized in the 2D patterned P3HT film. In a patterned cell, electrochromic diffraction was reversibly observed with a switching efficiency (R(DE)) of 2 and 2.5 for the 1D and 2D patterned cells, respectively.
EVIDENCE, an automated variant prioritization system, has been developed to facilitate whole exome sequencing analyses. This study investigated the diagnostic yield of EVIDENCE in patients with suspected genetic disorders. DNA from 330 probands (age range, 0-68 years) with suspected genetic disorders were subjected to whole exome sequencing. Candidate variants were identified by EVIDENCE and confirmed by testing family members and/or clinical reassessments. EVIDENCE reported a total 228 variants in 200 (60.6%) of the 330 probands. The average number of organs involved per patient was 4.5 ± 5.0. After clinical reassessment and/or family member testing, 167 variants were identified in 141 probands (42.7%), including 105 novel variants. These variants were confirmed as being responsible for 121 genetic disorders. A total of 103 (61.7%) of the 167 variants in 95 patients were classified as pathogenic or probably to be pathogenic before, and 161 (96.4%) variants in 137 patients (41.5%) after, clinical assessment and/or family member testing. Factor associated with a variant being regarded as causative includes similar symptom Go Hun Seo, Taeho Kim, and In Hee Choi contributed equally to this work.
This paper reports a new portable microfluidic platform, ''lab-on-a-display,'' that microparticles are manipulated by optoelectronic tweezers (OET) on a liquid crystal display (LCD). The OET has been constructed by assembling a ground layer, a liquid chamber, and a photoconductive layer. Without lens or optical alignments, the LCD image directly forms virtual electrodes on the photoconductive layer for dielectrophoretic manipulation. The lab-on-a-display was first realized by a conventional monochromatic LCD module and a light source brighter than 5,000 lux. It was successfully applied to the programmable manipulation of 45 lm polystyrene beads; more than 100 particles were transported with an optical imagedriven control, following the moving edge of the image at every moment. The effects of bead size and bias voltage on the manipulation speed were also investigated. Due to the portability and compatibility for disposable applications, this new platform has potential for programmable particle manipulation or chip-based bioprocessing including cell separation and bead-based analysis.
Fabrication of a flexible organic solar cell is demonstrated with an anode that is free of tin-doped indium oxide (ITO) by electrohydrodynamic (EHD) spraying of silver nanowires (Ag NWs). This methodology is applicable to fabricate patterned Ag NW thin-film electrodes for organic solar cells (OSCs). By optimizing the spray parameters and post-processing conditions, transparent electrodes with sheet resistances of $11 U sq À1 (on glass) and $20 U sq À1 (on polyethylene terephthalate, PET) and DC to optical conductivities of $70 (on PET) can be obtained at an optical transmittance of $80%. Bulk heterojunction OSCs are demonstrated with patterned Ag NW films serving as bottom transparent anodes on both glass substrates and flexible PET substrates. The photoactive layers are based on low band-gap polymers, poly [(4,8-bis-(2-ethylhexyloxy)-diyl] and phenyl-C61-butyric acid methyl ester. Under AM 1.5 illumination, fabricated cells have high power conversion efficiencies of 5.27% (on glass) and 3.76% (on PET). This study indicates that a Ag NW electrode prepared by EHD spraying can serve as an alternative to the ITO electrode, which also enables its potential application in practical and flexible OSCs.
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