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Objective This study investigated whether sleep and stress mutually interact to induce changes in white matter integrity.Methods Diffusion tensor imaging (DTI) was conducted on 36 participants (male=22, female=14; mean age=38.33±12.78 years). Participants were divided into three groups depending on their sleep quality and stress levels: poor sleepers with stress, poor sleepers without stress, and good sleepers. Sleep quality and stress level were evaluated using the Pittsburgh Sleep Quality Index and the Life Experiences Survey, respectively. Fractional anisotropy (FA) values were calculated employing DTI tractography.Results After controlling for age and sex, poor sleepers with stress exhibited a lower FA of the left inferior cerebellar peduncle (ICP) than did poor sleepers without stress (t=2.81, p=0.02). Poor sleepers without stress showed a higher FA of the right middle longitudinal fasciculus (MdLF) than did good sleepers (t=3.35, p=0.006).Conclusion The current study reports the effects of sleep, stress, and their interaction on the white matter integrities of the ICP and MdLF. ICP change seems to be associated with sleep disturbances related to stress, while MdLF change would be associated with sleep disturbances unrelated to stress.

Circadian rhythm is the internal clock that regulates physiological functions, including the sleep-wake cycle. Advancements in technology and lifestyle have negatively impacted the circadian rhythm, resulting in numerous sleep disorders. Because light is the most important “zeigeber” for synchronizing the circadian system, light therapy is effective for circadian rhythm sleep disorders. We compared light therapy glasses with a traditional light therapy box, summarized the characteristics of various light therapy glasses, and proposed future applications of wearable sleep technologies in light therapy.

The purpose of this nurse-led telehealth intervention was to support caregivers and infants during the difficult period of transition from the neonatal intensive care unit (NICU) to home.The Baby Steps project was designed using quality improvement methodology, and was implemented in April 2020 at a stand-alone pediatric institution in South Florida. Using a nurse-led telehealth model, follow-up nursing care was provided in the home setting for two weeks after discharge. Any infant cared for in the NICU and discharged to a home setting in the state of Florida was eligible for services. Encounters included assessment, anticipatory guidance, connection with community resources, and general support. Caregiver satisfaction, unplanned emergency care use, and 30-day readmissions were assessed.Within the first 18 months of the program, a total of 378 infants were enrolled, and 74.6% received follow-up services in the home setting (n = 282). Caregivers reported high satisfaction with the program (100% strongly agree or agree). There was a 46% decrease in 30-day readmissions from baseline rates, and a substantial decrease in use of emergency care services within a month of discharge as compared to infants discharged during the same time period who did not receive services (30.9% vs.13.8%).This nurse-led intervention was found to be a feasible and highly satisfactory approach to improve NICU patient outcomes and support caregivers during transition from hospital to home.Nurses can provide post-discharge telehealth support, which not only improves caregiver satisfaction but also decreases readmissions and emergency care use among NICU patients.

Jiye Lee,1,* Minjeong Kim,1,* Nambeom Kim,2 Yunjee Hwang,1 Kyung Hwa Lee,3,4 Jooyoung Lee,1 Yu Jin Lee,3 Seog Ju Kim1 1Department of Psychiatry, Sungkyunkwan University College of Medicine, Samsung Medical Center, Seoul, Republic of Korea; 2Department of Biomedical Engineering Research Center, Gachon University, Incheon, Republic of Korea; 3Department of Psychiatry and Center for Sleep and Chronobiology, Seoul National University, College of Medicine and Hospital, Seoul, Republic of Korea; 4Division of Child and Adolescent Psychiatry, Department of Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea*These authors contributed equally to this workCorrespondence: Yu Jin Lee, Department of Psychiatry and Center for Sleep and Chronobiology, Seoul National University, College of Medicine and Hospital, Seoul, Republic of Korea, Email ewpsyche@snu.ac.kr Seog Ju Kim, Department of Psychiatry, Sungkyunkwan University College of Medicine, Samsung Medical Center, Seoul, Republic of Korea, Email ksj7126@skku.eduIntroduction: We investigated the white matter integrity in shift and non-shift workers and its associations with sleep and activity.Methods: Diffusion tensor imaging (DTI) was performed on 61 shift workers and 31 non-shift workers. Their sleep and activity profiles were assessed using the Pittsburgh Sleep Quality Index (PSQI), sleep diaries, and actigraphy. Fractional anisotropy (FA) (a measure of white matter integrity) was calculated using DTI tractography.Results: Shift workers exhibited higher FA values in the bilateral anterior cingulum than did non-shift workers. An increased FA in the right anterior cingulum was correlated with poor sleep quality (ie, a high PSQI score) in shift workers. An increased FA in the right anterior cingulum was also correlated with higher actigraphic activity indices (the mesor and M10 indices) in shift workers.Discussion: The white matter integrity of the anterior cingulum was altered in shift workers, perhaps in association with sleep and activity disturbances.Keywords: shift work, DTI, cingulum, sleep, activity

Purpose The purpose of this study was to evaluate the in-gel strain and tear reduction provided by 2 skin protectant products that were applied as a liquid and allowed to dry, leaving behind a protective layer. Design Prospective, 3-group comparison cohort study using an in vitro model. Methods A fragile agar-based gel with an embedded bead was used in a custom device that applied variable interface pressures of 550, 1080, or 1600 Pa, respectively. The device then imparted 216 N of external shear force in 0.625-mm increments. The resulting strain in the gel was measured by digital image correlation. The strain at tearing was determined by observing the images of the gels and calculating the strain at that point. This approach was used to compare untreated gels to gels treated with one of 2 commercially available cyanoacrylate-based skin protectants. The results from the 3 groups were first analyzed by analysis of variance, followed by Tukey's Honestly Significant Difference test when indicated. Results We observed a proportional increase in interface pressure and strain that differed among the 3 groups. Specifically, the gels treated with a mixed polymer skin protectant had less pretearing strain than the control gel at both the 1080-Pa load (-15%, P = 3.64 × 10) and 1600 Pa-load (-20%, P = .03). The pure cyanoacrylate-treated gels had less strain than the control at 1080 Pa (-34%, P = 4.25 × 10) and 1600 Pa (-48%, P = 1.07 × 10); it also had less strain than the mixed polymer product at 1080 Pa (-19%, P = 5.38 × 10) and 1600 Pa (-28%, P = 3.88 × 10). In terms of protection from tearing, at an interface pressure of 1080 Pa, the control gel tore 80% of the time, the mixed polymer-treated gel tore 100% of the time, and the pure cyanoacrylate-treated gel did not tear (0/5, P = 8.84 × 10). Under a load of 1600 Pa, 100% of the control and mixed polymer-treated gels tore while none of the cyanoacrylate-treated gels did (P = 2.54 × 10). Conclusion The pure cyanoacrylate-based skin protectant provided the most protection, with consistent reductions in both strain and tearing. Both skin protectants reduced the initial in-gel strain; however, only the pure cyanoacrylate-treated product protected the gel from tears under the conditions tested. These results indicate that cyanoacrylate-based skin protectants can reduce shear strain and tearing in fragile elastic materials.

The aims of the Asthma Academy study were to (1) evaluate the telehealth performance of DNP students, (2) evaluate the perceived learning experience of DNP students and (3) investigate whether an association exists related to student performance and family caregiver outcomes.A descriptive study was conducted with doctor of nursing practice students.Students conducted telehealth visits to help family caregivers of children with asthma and were rated on their performance by two faculty members using a rubric. Student perception data were gathered via survey.Out of a total possible score of 15 points, the mean telehealth performance score of students was 13.38 points. Students indicated the telehealth experience was valuable and that they were satisfied with their learning. This model of leveraging telehealth to bridge nursing students to the community may be adapted to help family caregivers of children with various disease foci.

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Microalgae have been studied and tested for over 70 years. However, biodiesel, the prime target of the algal industry, has suffered from low competitiveness and current steps toward banning the internal combustion engine all over the world. Meanwhile, interest in reducing CO2 emissions has grown as the world has witnessed disasters caused by global warming. In this situation, in order to maximize the benefits of the microalgal industry and surmount current limitations, new breakthroughs are being sought. First, drop-in fuel, mandatory for the aviation and maritime industries, has been discussed as a new product. Second, methods to secure stable and feasible outdoor cultivation focusing on CO2 sequestration were investigated. Lastly, the need for an integrated refinery process to simultaneously produce multiple products has been discussed. While the merits of microalgae industry remain valid, further investigations into these new frontiers would put algal industry at the core of future bio-based economy.

Increased endothelial permeability, one of the earliest signs of endothelial dysfunction, is associated with the development of cardiovascular diseases such as hypertension and atherosclerosis. Recent studies suggest that the receptor for advanced glycation end products (RAGE) regulates endothelial permeability in inflammation. In the present study, we investigated the regulatory mechanism of RAGE in endothelial hyperpermeability induced by angiotensin II (Ang II), a well-known inflammatory mediator, and the potential therapeutic effect of soluble RAGE (sRAGE), a decoy receptor for RAGE ligands. For in vitro studies, Ang II-treated human umbilical vein endothelial cells (HUVECs) were treated with siRNA specific to either RAGE or sRAGE to disrupt RAGE-mediated signaling. Endothelial permeability was estimated using FITC-labeled dextran 40 and a resistance meter. To evaluate intercellular junction disruption, VE-cadherin expression was examined by western blotting and immunocytochemistry. Ang II increased the expression of the Ang II type 1 receptor (AT1R) and RAGE, and this increase was inhibited by sRAGE. sRAGE prevented Ang II-induced VE-cadherin disruption in HUVECs. For in vivo studies, Ang II-infused, atherosclerosis-prone apolipoprotein E knockout mice were utilized. Endothelial permeability was assessed by Evans blue staining of the aorta. Ang II increased endothelial barrier permeability, and this effect was significantly attenuated by sRAGE. Our data demonstrate that blockade of RAGE signaling using sRAGE attenuates Ang II-induced endothelial barrier permeability in vitro and in vivo and indicate the therapeutic potential of sRAGE in controlling vascular permeability under pathological conditions., Cardiovascular disease: Decoy protein improves blood vessel function A decoy version of a protein involved in regulating the leakiness of blood vessels can help ameliorate vascular problems that lead to high blood pressure and plaque deposition in the arteries. A team from South Korea led by Soyeon Lim from Catholic Kwandong University in Gangneung and Sungha Park from Yonsei University College of Medicine in Seoul induced hyper-permeability in both human vein cells and atherosclerosis-prone mice. They then blocked signaling through a membrane-bound protein called RAGE, a receptor that helps boost vessel permeability by using a soluble version of this same protein. In both the human cells and mouse models, this free-floating RAGE bound and blocked the receptor’s normal activator, leading to suppressed permeability and improved function of the blood vessel lining. This decoy strategy holds therapeutic promise for people prone to cardiovascular disease.

The recalcitrance of petroleum-based plastics causes severe environmental problems and has accelerated research into production of biodegradable polymers from inexpensive and sustainable feedstocks. Various microorganisms are capable of producing Polyhydroxybutyrate (PHB), a representative biodegradable polymer, under nutrient-limited conditions, among which CO

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The receptor for advanced glycation endproducts (RAGE) is an innate immunity receptor that has been implicated in the pathogenesis of atherosclerotic cardiovascular disease. However, the possibility that RAGE-mediated signaling is involved in angiotensin II (Ang II)-induced cardiac left ventricular hypertrophy has yet to be investigated. We therefore determined whether RAGE has a role in regulating pathological cardiac hypertrophy. Protein abundance was estimated using Western blotting and intracellular ROS level and phospho-p65 were detected using fluorescence microscopy. Enzyme-linked immunosorbent assay was used to detect HMGB1 and IL-1β. All in vitro experiments were performed using H9C2 cells. To induce cardiomyocyte hypertrophy, 300 nM Ang II was treated for 48 h and 2 µg/ml sRAGE was treated 1 h prior to addition of Ang II. sRAGE attenuated Ang II-induced cardiomyocyte hypertrophy by downregulating RAGE and angiotensin II type 1 receptor expression. Secretion levels of high motility group box 1 and interleukin-1β, estimated from a cell culture medium, were significantly reduced by sRAGE. Activated PKCs and ERK1/2, important signals in left ventricular hypertrophy (LVH) development, were downregulated by sRAGE treatment. Furthermore, we found that nuclear factor-κB and NOD-like receptor protein 3 (NLRP3) were associated with RAGE-mediated cardiomyocyte hypertrophy. In the context of these results, we conclude that RAGE induces cardiac hypertrophy through the activation of the PKCs-ERK1/2 and NF-κB-NLRP3-IL1β signaling pathway, and suggest that RAGE-NLRP3 may be an important mediator of Ang II-induced cardiomyocyte hypertrophy. In addition, we determined that inhibition of RAGE activation with soluble RAGE (sRAGE) has a protective effect on Ang II-induced cardiomyocyte hypertrophy.

In an effort to help meet the demand for promising renewable sources of energy, research into innovative downstream processing for microalgae biorefineries is actively underway. In the current work, we used octahedrally shaped ZnFe2O4 nanoparticles for both harvesting and disrupting the cells of microalgae. We were able to use ZnFe2O4 octahedrons as magnetic flocculants and cell-disruption agents because ZnFe2O4 nanoparticles have both magnetic and photocatalytic properties. The ZnFe2O4 octahedrons, when simply functionalized with the aminosilane N-[3-(trimethoxysilyl)propyl] ethylenediamine, enabled a rapid and energy-efficient harvesting of microalgae. Furthermore, the ZnFe2O4 octahedrons, well-known for having photocatalytic properties superior to those of ZnFe2O4 nanoparticles with other morphologies, were used to lyse the algal cell wall with the aid of H2O2 under simulated sunlight irradiation. We expect microalgae whose cells can be both magnetophoretically separated and lysed by the same ZnFe2O4 n...

The recalcitrance of petroleum-based plastics causes severe environmental problems and has accelerated research into production of biodegradable polymers from inexpensive and sustainable feedstocks. Various microorganisms are capable of producing Polyhydroxybutyrate (PHB), a representative biodegradable polymer, under nutrient-limited conditions, among which CO2-utilizing microorganisms are of primary interest. Herein, we discuss recent progress on bacterial strains including proteobacteria, purple non-sulfur bacteria, and cyanobacteria in terms of CO2-containing carbon sources, PHB-production capability, and genetic modification. In addition, this review introduces recent technical approaches used to improve PHB production from CO2 such as two-stage bioprocesses and bioelectrochemical systems. Challenges and future perspectives for the development of economically feasible PHB production are also discussed. Finally, this review might provide insights into the construction of a closed-carbon-loop to cope with climate change.

Reaching high efficiencies in organic photovoltaics is often limited by dissociating charge transfer states at electron donor–acceptor interfaces due to their large binding energies and rapid geminate recombination. By adding a high-permittivity small molecule, camphoric anhydride, at 20 wt % to a polymer–fullerene bulk heterojunction photovoltaic device, we increased the film permittivity, reduced the charge transfer state energy, and increased the power conversion efficiency by 75%. At higher concentrations, the camphoric anhydride begins to crystallize and phase separate from the bulk heterojunction, causing the permittivity and power conversion efficiency to decrease. Adding camphoric anhydride in low concentrations is an effective strategy to increase permittivity and reduce recombination at the donor–acceptor interface and as a result increase organic photovoltaic efficiency in bulk heterojunction devices.

Four dogs were brought to the Veterinary Medicine Teaching Hospital of Seoul National University (VMTH SNU) with a history of hind limb ataxia, three with pain, one without pain. Three of the four showed weak to absent femoral pulses and cold extremities. Thromboembolism was identified by ultrasonography in the external and/or internal iliac arteries. A thrombolytic agent, recombinant tissue plasminogen activator (rt-PA), was administered (0.5-1 mg/kg, every 60-120 min, 3-5 doses). Two dogs (Cases 2 and 3), which were instantly provided rt-PA treatment, survived 6 and 17 months, respectively, although hematemesis and hematochezia were observed during treatment. In the other two dogs (Cases 1 and 4), rt-PA was administered 4 and 28 days after the appearance of pelvic limb symptoms, which may have limited the benefits of the treatment. When rt-PA treatment is instituted instantly and the side effects are monitored thoroughly during treatment, a good prognosis might be expected in canine aortic thromboembolism. For this reason, we suggest that rt-PA treatment should be initiated immediately if thromboembolism is identified.

Energy-saving, high-efficiency cell disruption is a critical step for recovery of thermolabile antioxidant astaxanthin from Haematococcus pluvialis cyst cells of rigid cell-wall structure. In this study, as room-temperature green solvents, 10 types of 1-ethyl-3-methylimidazolium ([Emim])-based ionic liquids (ILs) were compared and evaluated for their abilities to disrupt H. pluvialis cyst cells for astaxanthin/lipid extraction. Among the 10 ILs tested, 3 [Emim]-based ILs with HSO4, CH3SO3, and (CF3SO2)2N anions were selected based on astaxanthin/lipid extraction performance and synthesis cost. When pretreated with IL/water mixtures, intact cyst cells were significantly torn, broken or shown to release cytoplasmic components, thereby facilitating subsequent separation of astaxanthin/lipid by hexane. However, excess IL pretreatments at high temperature/IL dosages and longer incubation times significantly deteriorated lipid and/or astaxanthin. Under optimized mild conditions (6.7% (v/v) IL in water solution, 30 °C, 60 min), almost complete astaxanthin recoveries (>99%) along with moderate lipid extractions (∼82%) could be obtained.

Milking of microalgae, the process of reusing the biomass for continuous production of target compounds, can strikingly overcome the time and cost constraints associated with biorefinery. This process can significantly improve production efficiency of highly valuable chemicals, for example, astaxanthin (AXT) from Haematococcus pluvialis. Detailed understanding of the biological process of cell survival and AXT reaccumulation after extraction would be of great help for successful milking. Here we report extraction of AXT from a single cell of H. pluvialis through incision of the cell wall by a gold nanoscalpel (Au-NS), which allows single-cell analysis of wound healing and reaccumulation of AXT. Interestingly, upon the Au-NS incision, the cell could reaccumulate AXT at a rate two times faster than the control cells. Efficient extraction as well as minimal cellular damage, keeping cells alive, could be achieved with the optimized shape and dimensions of Au-NS: a well-defined sharp tip, thickness under 300 nm, and 1-3 μm of width. The demonstration of regenerative extraction of AXT at a single cell level hints toward the potential of a milking process for continuous recovery of target compounds from microalgae while keeping the cells alive.

In this study, a new development in thermoplastics was examined: a poly(cyclohexylthioacrylate) containing a sulfur atom in a polymer chain with a high refractive index. The poly(cyclohexylthioacrylate) was synthesized by the free radical polymerization of cyclohexylthioacrylate. Transparent polymer films, fabricated by spin-coating from the polymer solution, exhibited a high refractive index of 1.55244 at 637 nm and low birefringence of 0.0001. The thermal decomposition temperature (T d ) of the polymer was in the range of 355-363 °C, which indicates good thermal stability, while its glass transition temperature was 65 °C.

Reduced-dimensionality materials for photonic and optoelectronic applications including energy conversion, solid-state lighting, sensing, and information technology are undergoing rapid development. The search for novel materials based on reduced-dimensionality is driven by new physics. Understanding and optimizing material properties requires characterization at the relevant length scale, which is often below the diffraction limit. Three important material systems are chosen for review here, all of which are under investigation at the Molecular Foundry, to illustrate the current state of the art in nanoscale optical characterization: 2D semiconducting transition metal dichalcogenides; 1D semiconducting nanowires; and energy-transfer in assemblies of 0D semiconducting nanocrystals. For each system, the key optical properties, the principal experimental techniques, and important recent results are discussed. Applications and new developments in near-field optical microscopy and spectroscopy, scanning probe microscopy, and cathodoluminescence in the electron microscope are given detailed attention. Work done at the Molecular Foundry is placed in context within the fields under review. A discussion of emerging opportunities and directions for the future closes the review.

The authors describe the synthesis and characterization of the polyimide (PI) series containing a 2,5-bis(4-aminophenylenesulfanyl)-3,4-ethylenedithiothiophene (APSEDTT) moiety in their main chain. The APSEDTT monomer with high sulfur content was prepared and polymerized with several aromatic dianhydrides such as 4,4′-[p-thio bis(phenylenesulfanyl)]diphthalic anhydride (3SDEA), 4,4′-biphthalic anhydride (BPDA), and 4,4′-oxydiphthalic anhydride (ODPA) by the traditional two-step polycondensation procedure. All PIs exhibited high transparency, higher than 75% at 550 nm for a thickness of about 20 μm and good thermal properties such as thermal decomposition temperatures (T10%) in the range of 409–521 °C. In addition, the PIs have extraordinarily excellent optical properties in refractive index and birefringence as originally designed. In particular, the PI derived from APSEDTT and 3SDEA showed a high refractive index (1.7586), and a low birefringence (0.0087) because of their very high sulfur content (27.7%). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 944–950

Haematococcus pluvialis, in the dormant aplanospore (cyst) status after 30 d of cultivation, accumulates high levels of a superpotent antioxidant, astaxanthin, which has been demonstrated to have enormous therapeutic benefits. However, owing to the robust structure of its trilayered cell wall, the recovery of astaxanthin from the cyst cells remains an energy-intensive process. In the present study, a novel strategy utilizing a short-period germination based on the natural life cycle of H. pluvialis was developed as an energy-efficient pretreatment for the extraction of astaxanthin using ionic liquids (ILs) as green solvents. The germination resulted in damage and deconstruction of the cyst cell wall, and thereby facilitated the extraction of astaxanthin by ILs at room temperature. By this natural pretreatment with 1-ethyl-3-methylimidazolium ethylsulfate for a very short reaction time of 1 min, a high astaxanthin yield of 19.5 pg per cell was obtained, which was about 82% of a conventional volatile organic solvent extraction by strong, 30 000 psi French-pressure-cell homogenization. The maximal astaxanthin-extraction yield from H. pluvialis cells was observed for 12–18 h germination. The germination rate furthermore could be improved by manipulating the nutritional composition (especially the nitrate concentration) of the culture medium. In light of these results, it can be posited that natural germination following the principles of green chemistry can be a uniquely simple method of robust microalgal cyst cell pretreatment and extraction of astaxanthin with room-temperature ILs.

Electrically controlling resonant energy transfer of optical emitters provides a novel mechanism to switch nanoscale light sources on and off individually for optoelectronic applications. Graphene's optical transitions are tunable through electrostatic gating over a broad wavelength spectrum, making it possible to modulate energy transfer from a variety of nanoemitters to graphene at room temperature. We demonstrate photoluminescence switching of individual colloidal quantum dots by electrically tuning their energy transfer to graphene. The gate dependence of energy transfer modulation confirms that the transition occurs when the Fermi level is shifted over half the emitter's excitation energy. The modulation magnitude decreases rapidly with increasing emitter-graphene distance (d), following the 1/d(4) rate trend unique to the energy transfer process to two-dimensional materials.

In this study, the acrylic pressure sensitive adhesive (PSA) for the optical functionality sheet was prepared by blending liquid isoprene rubber. The acrylic PSA was synthesized with butyl acrylate, acrylic acid, 2-ethylhexyl acrylate and 2-hydroxyethyl methacrylate. Toluene was used to a solvent for polymerization. Liquid isoprene rubber (LIR-50) was blended with the acrylic PSA and blend ratio was 0 ~ 50 wt%. According to the results, the adhesive transfer, which was the big problem of acrylic adhesive, was reduced with the addition of LIR-50. The secondary bonding of LIR-50 with substrate did not occurred due to absence of polar group in LIR-50. The peel strength and adhesive transfer were decreased by UV curing and the degreed of decrease depended on the amounts of photoinitiator and UV irradiation time. On the other hand holding power increased drastically by increasing amounts of photoinitiator and UV irradiation time.

Singlet exciton fission, a process that generates two excitons from a single photon, is perhaps the most efficient of the various multiexciton-generation processes studied to date, offering the potential to increase the efficiency of solar devices. But its unique characteristic, splitting a photogenerated singlet exciton into two dark triplet states, means that the empty absorption region between the singlet and triplet excitons must be filled by adding another material that captures low-energy photons. This has required the development of specialized device architectures. In this Account, we review work to develop devices that harness the theoretical benefits of singlet exciton fission. First, we discuss singlet fission in the archetypal material, pentacene. Pentacene-based photovoltaic devices typically show high external and internal quantum efficiencies. They have enabled researchers to characterize fission, including yield and the impact of competing loss processes, within functional devices. We review in situ probes of singlet fission that modulate the photocurrent using a magnetic field. We also summarize studies of the dissociation of triplet excitons into charge at the pentacene-buckyball (C60) donor-acceptor interface. Multiple independent measurements confirm that pentacene triplet excitons can dissociate at the C60 interface despite their relatively low energy. Because triplet excitons produced by singlet fission each have no more than half the energy of the original photoexcitation, they limit the potential open circuit voltage within a solar cell. Thus, if singlet fission is to increase the overall efficiency of a solar cell and not just double the photocurrent at the cost of halving the voltage, it is necessary to also harvest photons in the absorption gap between the singlet and triplet energies of the singlet fission material. We review two device architectures that attempt this using long-wavelength materials: a three-layer structure that uses long- and short-wavelength donors and an acceptor and a simpler, two-layer combination of a singlet-fission donor and a long-wavelength acceptor. An example of the trilayer structure is singlet fission in tetracene with copper phthalocyanine inserted at the C60 interface. The bilayer approach includes pentacene photovoltaic cells with an acceptor of infrared-absorbing lead sulfide or lead selenide nanocrystals. Lead selenide nanocrystals appear to be the most promising acceptors, exhibiting efficient triplet exciton dissociation and high power conversion efficiency. Finally, we review architectures that use singlet fission materials to sensitize other absorbers, thereby effectively converting conventional donor materials to singlet fission dyes. In these devices, photoexcitation occurs in a particular molecule and then energy is transferred to a singlet fission dye where the fission occurs. For example, rubrene inserted between a donor and an acceptor decouples the ability to perform singlet fission from other major photovoltaic properties such as light absorption.

Purpose: The present study was conducted to investigate whether the directions of eye movement in playing computer games for certain period affected the change of near point of convergence (NPC) and fusional reserve (FR) or not. Methods: Total 40 subjects in 20s who have the visual acuity of 1.0 or higher without any ocular disease and accommodative dysfunction were asked to successively play computer games. After the subjects were moving eyes in horizontal and vertical directions for 40 and 90 minutes, their horizontal fusional reserves, vertical fusional vergence and near point of convergence were measured. Results: The near point of convergence showed a tendency to be receded after computer gaming in the horizontal and vertical directions, and both of horizontal and vertical fusional reserves were significantly reduced. The range of declined fusional reserves and receded near point of convergence after computer gaming for 90 minutes was smaller than those after computer gaming for 40 minutes. The change of binocular vision was affected by the horizontal eye movement rather than the vertical movement when analyzed by the direction of eye movement. Conclusions: This study revealed that the change in FR and NPC was different along with dominant direction of eye movement during visual display terminal (VDT) tasks. Therefore, the adjustment of VDT working time is required to prevent the dysfunction of binocular vision according to the dominant direction of eye movement during VDT task.