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CCCTC-binding factor (CTCF) critically contributes to 3D chromatin organization by determining topologically associated domain (TAD) borders. Although CTCF primarily binds at TAD borders, there also exist putative CTCF-binding sites within TADs, which are spread throughout the genome by retrotransposition. However, the detailed mechanism responsible for masking the putative CTCF-binding sites remains largely elusive. Here, we show that the ATP-dependent chromatin remodeler, chromodomain helicase DNA-binding 4 (CHD4), regulates chromatin accessibility to conceal aberrant CTCF-binding sites embedded in H3K9me3-enriched heterochromatic B2 short interspersed nuclear elements (SINEs) in mouse embryonic stem cells (mESCs). Upon CHD4 depletion, these aberrant CTCF-binding sites become accessible and aberrant CTCF recruitment occurs within TADs, resulting in disorganization of local TADs. RNA-binding intrinsically disordered domains (IDRs) of CHD4 are required to prevent this aberrant CTCF binding, and CHD4 is critical for the repression of B2 SINE transcripts. These results collectively reveal that a CHD4-mediated mechanism ensures appropriate CTCF binding and associated TAD organization in mESCs.

We report on SPICE circuit modeling of traveling-wave superconducting-nanowire single-photon detectors integrated with Si3N4/SiO2 optical waveguides.

CCCTC-binding factor (CTCF) critically contributes to 3D chromatin organization by determining topologically associated domain (TAD) borders. Although CTCF primarily binds at TAD borders, there also exist putative CTCF-binding sites within TADs, which are spread throughout the genome by retrotransposition. However, the detailed mechanism responsible for masking the putative CTCF-binding sites remains largely elusive. Here, we show that the ATP-dependent chromatin remodeler, chromodomain helicase DNA-binding 4 (CHD4), regulates chromatin accessibility to conceal aberrant CTCF-binding sites embedded in H3K9me3-enriched heterochromatic B2 short interspersed nuclear elements (SINEs) in mouse embryonic stem cells (mESCs). Upon CHD4 depletion, these aberrant CTCF-binding sites become accessible and aberrant CTCF recruitment occurs within TADs, resulting in disorganization of local TADs. RNA-binding intrinsically disordered domains (IDRs) of CHD4 are required to prevent this aberrant CTCF binding, and CHD4 is critical for the repression of B2 SINE transcripts. These results collectively reveal that a CHD4-mediated mechanism ensures appropriate CTCF binding and associated TAD organization in mESCs.

We report on design, fabrication, and characterization of silicon quantum photonic integrated circuits comprising superconducting nanostripe single-photon detectors integrated with dielectric optical waveguides. In order to enhance absorption of photons by the superconducting nanostripes, the detectors are located directly on the dielectric waveguide core.

Anti-Stokes photoluminescence from colloidal CdSeS/ZnS quantum dots (QDs) is observed. The QDs were inserted into the core of wider-bandgap SiO2/Si3N4/SiO2 structure by thin film deposition and confirmed as promising nanoemitters for laser cooling due to efficient anti-Stokes emission. The nanoemitters were optically pumped by semiconductor lasers coupled to the waveguides using free-space optics. A direct evidence of local optical cooling in the waveguide structure has been demonstrated with a luminescence thermometry based on the detection of photoluminescence signal phase change versus power of the pumping laser, using a lock-in amplifier.

We report on design, fabrication, and characterization of superconducting nanostripe single-photon detectors integrated with dielectric optical waveguides, whereby part of the upper cladding is removed to enhance absorption of photons by the superconducting nanostripes.

Phosphorus-free multiple-quantum-well lasers with In0.53Ga0.47As wells, In0.53Al0.2Ga0.27As barriers, and In0.53Al0.47As claddings have been fabricated as Fabry-Perot devices of different lengths and widths. Their current-voltage and light-current characteristics have been measured over a wide temperature range from 200 K down to 20 K. These data have been analyzed for experimental information on carrier freeze out, gain changes related to temperature, temperature-dependence of series resistance, and prospects for high-performance lasers operating at cryogenic temperatures.

GaSb-based multiple-quantum-well lasers with In0.2Ga0.8Sb wells, Al0.35Ga0.65Sb barriers, and Al0.9Ga0.1Sb claddings have been fabricated as broad-area Fabry-Perot devices of dimensions 1000 μm × 800 μm. Their current-voltage and light-current characteristics, as well as emission spectra have been measured over a wide temperature range from 280 K down to 20 K. These data have been analyzed for experimental information on carrier freeze out, gain changes related to temperature, temperature-dependence of series resistance, and prospects for high-performance lasers operating at cryogenic temperatures.

Stem cell fate is largely determined by cellular signaling networks and is heavily dependent on the supplementation of exogenous recombinant proteins into culture media; however, uneven distribution and inconsistent stability of recombinant proteins are closely associated with the spontaneous differentiation of pluripotent stem cells (PSCs) and result in significant costs in large-scale manufacturing. Here, we report a novel PSC culture system via wirelessly controllable optical activation of the fibroblast growth factor (FGF) signaling pathway without the need for supplementation of recombinant FGF2 protein, a key molecule for maintaining pluripotency of PSCs. Using a fusion protein between the cytoplasmic region of the FGF receptor-1 and a light-oxygen-voltage domain, we achieved tunable, blue light-dependent activation of FGF signaling in human and porcine PSCs. Our data demonstrate that a highly controllable optical stimulation of the FGF signaling pathway is sufficient for long-term maintenance of PSCs, without the loss of differentiation potential into three germ layers. This culture system will be a cost-effective platform for a large-scale stem cell culture.

The continuing controversy regarding the validity of assuming different photon lifetimes for counterpropagating modes in whistle-geometry ring resonators has led us to re-examine the commonly held view that coupling coefficients between any two ports in Y-junction couplers (regardless of their symmetry) do not depend on the direction of propagation. Rigorous three-dimensional finite-difference time-domain simulations show that the common assumptions about the operation o three-port couplers are sometimes grossly incorrect, as they arise from an oversimplified analytical model. An explanation is given why our results do not violate the Helmholtz reciprocity principle.

Research on drug courts over the past decades has focused primarily on individual predictors of success and/or has examined the effectiveness of various judicial as well as therapeutic intervention strategies. To broaden our understanding of recovery as it occurs within the context of social networks, the following paper discusses the application of a new network-based framework of recovery capital. Participants in a small rural southeastern Adult Drug Court filled out a series of questionnaires and participated in a number of semi-structured interviews that assessed the availability of network-based recovery capital. The findings of this exploratory study suggest that participants possess restrictive resource portfolios and tend to over-rely on therapeutic (artificial) networks for support. Select implications for future research and treatment interventions are discussed.

Accurate detection of variants and long-range haplotypes in genomes of single human cells remains very challenging. Common approaches require extensive in vitro amplification of genomes of individual cells using DNA polymerases and high-throughput short-read DNA sequencing. These approaches have two notable drawbacks. First, polymerase replication errors could generate tens of thousands of false-positive calls per genome. Second, relatively short sequence reads contain little to no haplotype information. Here we report a method, which is dubbed SISSOR (single-stranded sequencing using microfluidic reactors), for accurate single-cell genome sequencing and haplotyping. A microfluidic processor is used to separate the Watson and Crick strands of the double-stranded chromosomal DNA in a single cell and to randomly partition megabase-size DNA strands into multiple nanoliter compartments for amplification and construction of barcoded libraries for sequencing. The separation and partitioning of large single-stranded DNA fragments of the homologous chromosome pairs allows for the independent sequencing of each of the complementary and homologous strands. This enables the assembly of long haplotypes and reduction of sequence errors by using the redundant sequence information and haplotype-based error removal. We demonstrated the ability to sequence single-cell genomes with error rates as low as 10-8 and average 500-kb-long DNA fragments that can be assembled into haplotype contigs with N50 greater than 7 Mb. The performance could be further improved with more uniform amplification and more accurate sequence alignment. The ability to obtain accurate genome sequences and haplotype information from single cells will enable applications of genome sequencing for diverse clinical needs.

Greatly enhanced high-speed modulation performance has been recently predicted in numerical calculations for a novel injection-locking scheme involving a distributed Bragg reflector master laser monolithically integrated with a unidirectional whistle-geometry semiconductor microring laser. Operation of these devices relies on the assumption of large difference between modal losses experienced by counterpropagating modes. In this work, we confirm the unidirectionality of the whistle-geometry configuration through rigorous three-dimensional finite-difference timedomain (FDTD) simulation by showing a strong asymmetry in photon lifetimes between the two counterpropagating modes. We also show that similar asymmetry occurs in three-port couplers, whose structure resembles the coupling section of whistle-geometry lasers. We explain why these results do not violate the Helmholtz reciprocity principle.

Accurate detection of variants and long-range haplotypes in genomes of single human cells remains very challenging. Common approaches require extensive in vitro amplification of genomes of individual cells using DNA polymerases and high-throughput short-read DNA sequencing. These approaches have two notable drawbacks. First, polymerase replication errors could generate tens of thousands of false positive calls per genome. Second, relatively short sequence reads contain little to no haplotype information. Here we report a method, which is dubbed SISSOR (Single-Stranded Sequencing using micrOfluidic Reactors), for accurate single-cell genome sequencing and haplotyping. A microfluidic processor is used to separate the Watson and Crick strands of the double-stranded chromosomal DNA in a single cell and to randomly partition megabase-size DNA strands into multiple nanoliter compartments for amplification and construction of barcoded libraries for sequencing. The separation and partitioning of large single-stranded DNA fragments of the homologous chromosome pairs allows for the independent sequencing of each of the complementary and homologous strands. This enables the assembly of long haplotypes and reduction of sequence errors by using the redundant sequence information and haplotype-based error removal. We demonstrated the ability to sequence single-cell genomes with error rates as low as 10−8 and average 500kb long DNA fragments that can be assembled into haplotype contigs with N50 greater than 7Mb. The performance could be further improved with more uniform amplification and more accurate sequence alignment. The ability to obtain accurate genome sequences and haplotype information from single cells will enable applications of genome sequencing for diverse clinical needs.

We investigated the optical properties of Ge1−x Se x and Ge1−x−y Se x As y amorphous films by using spectroscopic ellipsometry and Raman spectroscopy. The dielectric functions and absorption coefficients (α) of the amorphous films were determined from the measured ellipsometric angles (Ψ,Δ). We obtained the optical gap energies and the Urbach energies from the absorption coefficients and found a strong bowing effect in the optical gap energy of Ge1−x−y Se x As y , where the endpoint binaries were Ge0.50Se0.50 and Ge0.31As0.69. Based on the correlation between the optical gap energies and the Urbach energies, we attributed the large bowing parameter to electronic disorder. Using Raman spectroscopy, we measured the phonon modes and discussed the composition dependence of the phonon peak frequencies and lineshapes in terms of structural units. Based on the composition dependence of the phonons in Ge1−x−y Se x As y , we identified the phonon modes of Ge0.31As0.69. A resonant Raman phenomenon was observed in Ge0.40Se0.60 at a laser excitation of 514 nm (2.41 eV). We verified that this laser energy corresponded to the transition energy of Ge0.40Se0.60 by using the second derivative of the dielectric function of Ge0.40Se0.60.

Two kinds of anthracene derivative thin films, 2, 6-bis((4-hexylphenyl)ethynyl)-9, 10-bis(phenyl ethynyl)anthracene (B-ant-THB) and 9, 10-bis((4-hexyl phenyl)ethynyl)-2, 6-bis (phenyl ethynyl) anthracene (HB-ant-TB), were synthesized to investigate their optical properties. The difference between the two anthracene derivatives consisted of the position of the 1-ethynyl-4-hexylbenzene group substitution into an anthracene ring. We measured the optical properties of the anthracene derivatives by using photoluminescence (PL), transmittance spectroscopy, and spectroscopic ellipsometry. The dielectric functions of the two films were similar with respect to transition energies, but were different in terms of amplitudes. The optical band gap energies of the B-ant-THB and the HB-ant-TB film states were estimated to be 2.45 eV and 2.34 eV, respectively, whereas density functional theory (DFT) calculations of isolated molecular states showed the same value of 2.42 eV. The large bathochromic shift of the HB-ant-TB film state compared to the DFT calculation is attributed to strong intermolecular coupling between the HB-ant-TB molecules in the crystalline film because the HB-ant-TB film has higher crystallinity than the B-ant-THB film. The symmetric structures of the transmittance and PL spectra of the anthracene derivative films were observed as distinct peaks having similar vibrational energy levels for the singlet ground state and the first excited state.

Given the severe lack of sufficiently detailed data, there is very little measurement or quantification of the contributions by online intermediaries in the academic literature. Intermediaries and platforms are loosely defined by lawmakers and national statistics for any meaningful analysis; available data suggests online intermediaries do not yet interact with many of the sectors often mentioned as adversely affected by digitalisation, while available data on productivity and trade leads to counterintuitive conclusions. We examine to what extent the economic impact of intermediaries may differ in the US and the EU – two markets with comparable set up of market institutions and actors – and conclude that the impact is similar in terms of input, outputs, productivity and trade. Yet the online intermediaries have created different incentives in the US and the EU. Conclusion is the political economy of advertising: Online advertising continues to grow at the expense of TV, magazines and newspapers. Europe is the only geographic area in the world that has seen the advertising expenditures fall (– 0.8 % compared to +0.6 % in North America). Furthermore, traditional media is the most important supplier of inputs to online intermediaries in the US, which turned a zero-sum game between into a condition of co-dependence.This redistributive mechanism – where online intermediaries channel profits back into traditional media through advertising – could not be confirmed to exist in the EU. This lack of co-dependency is one possible determinant to why stakeholder interests are differently aligned in the EU compared to the US.

This paper provides a robust and significant explanation of how the costs of data regulation affect downstream industries in an economy. In doing so we first select observable regulatory barriers that explicitly inhibit the domestic and cross-border movement of data, which are currently being implemented by various governments. Second, we calculate the costs of these data regulations for domestic industries through establishing an empirical link between regulation in data and domestic downstream performance at industry level across a set of countries. As such, this paper is the first work that attempts to analyse this connection econometrically by setting up a proxy index of data regulation using a typology of existing indices of administrative barriers. We show that the type of regulations prevalent in data indeed tends to affect downstream industry performance of industries that depend more heavily on data services for the countries under consideration in our study. Finally, the negative performance outcomes as a result of data regulation in these countries are employed in a general equilibrium analysis using the Global Trade Analysis Project (GTAP) in order to estimate the impact on country-specific GDP, industry production, and foreign trade.

Histone-modifying enzymes play a pivotal role in gene expression and repression. In human, DOT1L (Dot1-like) is the only known histone H3 lysine 79 methyltransferase. hDOT1L is associated with transcriptional activation, but the general mechanism connecting hDOT1L to active transcription remains largely unknown. Here, we report that hDOT1L interacts with the phosphorylated C-terminal domain of actively transcribing RNA polymerase II (RNAPII) through a region conserved uniquely in multicellular DOT1 proteins. Genome-wide profiling analyses indicate that the occupancy of hDOT1L largely overlaps with that of RNAPII at actively transcribed genes, especially surrounding transcriptional start sites, in embryonic carcinoma NCCIT cells. We also find that C-terminal domain binding or H3K79 methylations by hDOT1L is important for the expression of target genes such as NANOG and OCT4 and a marker for pluripotency in NCCIT cells. Our results indicate that a functional interaction between hDOT1L and RNAPII targets hDOT1L and subsequent H3K79 methylations to actively transcribed genes.

We present free-floating amphiphilic picoliter microcarriers for multiplexed loading in a microfluidic device. The amphiphilic microcarrier is composed of encoded hydrophobic hexagonal outer structure and hydrophilic inner structure. We fabricate these free-floating droplet carriers and assemble them in a microfluidic device for a demonstration of multiplexed liquid loading. Picoliter loading is performed by serial solution exchange of aqueous and oil phase solution. We are able to precisely adjust the loaded volume by varying the diameter and depth of the microcarrier. We also fabricate arbitrary shaped microwells and load picoliter droplets into them. A microbead suspension is also used to demonstrate mixing via continuous oil flow. Further development of this work may be applicable to high-throughput multiplexed assays using quantized liquid loading in a microfluidic environment.

A sheet resistance- and optical transmittance-tunable amorphous ZnSnO3 (ZTO) multilayer electrode created through the insertion of a nano-scale Ag layer is demonstrated as an indium-free transparent conducting electrode for cost-efficient inverted organic solar cells (IOSCs). Due to the antireflection effect, the ZTO/Ag/ZTO/glass exhibited a high transmittance of 86.29% in the absorption wavelength region of the organic active layer and a low resistivity of 3.24×10−5 Ω cm, even though the ZTO/Ag/ZTO electrode was prepared at room temperature. The metallic conductivity of the electrode indicates that its electrical conductivity is dominated by the nano-scale Ag metal layer. In addition, optimization and control of the thickness of the nano-scale Ag layer are important in obtaining highly transparent ZTO/Ag/ZTO electrodes, because antireflection is strongly influenced by Ag thickness. Moreover, IOSCs fabricated on optimized ZTO/Ag/ZTO electrodes with Ag thicknesses of 12 nm showed power conversion efficiencies (2.55%) comparable to that of an IOSC prepared on a crystalline ITO electrode (2.45%), due to the low sheet resistance and high optical transmittance in the range of 400–600 nm. The performances of ZTO/Ag/ZTO multilayer electrodes indicate that ZTO/Ag/ZTO multilayers are promising as indium-free, transparent electrode substitutes for conventional ITO electrodes in cost-efficient IOSCs.

Many creatures in nature, such as butterflies and peacocks, display unique brilliant colours, known as ‘structural colours’, which result from the interaction of light with periodic nanostructures on their surfaces. Mimicking such nanostructures found in nature, however, requires state-of-the-art nanofabrication techniques that are slow, expensive and not scalable. Herein, we demonstrate high-resolution patterning of multiple structural colours within seconds, based on successive tuning and fixing of colour using a single material along with a maskless lithography system. We have invented a material called ‘M-Ink’, the colour of which is tunable by magnetically changing the periodicity of the nanostructure and fixable by photochemically immobilizing those structures in a polymer network. We also demonstrate a flexible photonic crystal for the realization of structural colour printing. The simple, controllable and scalable structural colour printing scheme presented may have a significant impact on colour production for general consumer goods. Maskless high-resolution patterning of structural colours is demonstrated using a new material called ‘M-Ink’. The period of the material is patterned magnetically and a photochemical process immobilizes the structure in a polymer network.

Accurate measurement of RNA transcripts from single cells will enable the precise classification of cell types and characterization of the heterogeneity in cell populations that play key roles in normal cellular physiology and diseases. As a step towards this end, we have developed a microfluidic device and methods for automatic hydrodynamic capture of single mammalian cells and subsequent immobilization and digital counting of polyadenylated mRNA molecules released from the individual cells. Using single-molecule fluorescence imaging, we have demonstrated that polyadenylated mRNA molecules from single HeLa cells can be captured within minutes by hybridization to polydeoxyribothymidine oligonucleotides covalently attached on the glass surface in the device. The total mRNA molecule counts in the individual HeLa cells are found to vary significantly from one another. Our technology opens up the possibility of direct digital enumeration of RNA transcripts from single cells with single-molecule sensitivity using a single integrated microfluidic device.

RNA-sequencing (RNA-seq) measures the quantitative change in gene expression over the whole transcriptome, but it lacks spatial context. In contrast, in situ hybridization provides the location of gene expression, but only for a small number of genes. Here we detail a protocol for genome-wide profiling of gene expression in situ in fixed cells and tissues, in which RNA is converted into cross-linked cDNA amplicons and sequenced manually on a confocal microscope. Unlike traditional RNA-seq, our method enriches for context-specific transcripts over housekeeping and/or structural RNA, and it preserves the tissue architecture for RNA localization studies. Our protocol is written for researchers experienced in cell microscopy with minimal computing skills. Library construction and sequencing can be completed within 14 d, with image analysis requiring an additional 2 d.

Cross-border data flows are an integral mechanism of today's economy, impacting a country's competitiveness and growth. All economic sectors rely on secure, cost-efficient and real-time access to data. A requirement that all data-related business processes must take place within a country does not only affect social networks and e-commerce, but any business directly or indirectly. The Russian privacy legislation (the "OPD Law") has been amended by a new law (FZ-242) that includes a clear data localisation requirement. Article 18 §5 of the law requires data operators to ensure that any collection or use of personal data of Russian citizens is made using databases located inside Russia. Data localisation leads to productivity losses as firms may not be able to use services provided from abroad, or must set up their own domestic data centres inside Russia. Experience shows that the data-intensive service industry will pass on new costs from regulatory compliance to other sectors of the economy, and the productivity loss it generates leads to lower returns of investment. (...)

SummaryLIN28-mediated processing of the microRNA (miRNA) let-7 has emerged as a multilevel program that controls self-renewal in embryonic stem cells. LIN28A is believed to act primarily in the cytoplasm together with TUT4/7 to prevent final maturation of let-7 by Dicer, whereas LIN28B has been suggested to preferentially act on nuclear processing of let-7. Here, we find that SET7/9 monomethylation in a putative nucleolar localization region of LIN28A increases its nuclear retention and protein stability. In the nucleoli of human embryonic stem cells, methylated LIN28A sequesters pri-let-7 and blocks its processing independently of TUT4/7. The nuclear form of LIN28A regulates transcriptional changes in MYC-pathway targets, thereby maintaining stemness programs and inhibiting expression of early lineage-specific markers. These findings provide insight into the molecular mechanism underlying the posttranslational methylation of nuclear LIN28A and its ability to modulate pluripotency by repressing let-7 miRNA expression in human embryonic stem cells.

In the wide-ranging policy debate on data privacy, the economic impact of regulation has thus far received very little attention. Yet data privacy legislation has the potential to affect different groups and countries asymmetrically, leading to important redistributive effects. This paper aims to illustrate the economic impact of data regulation, using the EU’s General Data Protection Regulation (GDPR) as an example, and using econometric methods (GTAP) commonly used in trade economics. GDPR introduces restrictions on cross-border trade flows, which affects input prices to the service industry, and in turn, EU exports, with a direct welfare effects on the EU is a loss of up to € 260 per European citizen. The findings of this study have important implications for the discussions around policy design and regulatory efficiency. The severe economic impact of the GDPR proposal demonstrates that data connectivity and economic interdependency effectively limit the policy space for non-economic regulation. Moreover, this paper shows that mercantilist data restrictions are counterproductive and affect the protecting market more than those who are restricted in accessing it.

We report a method for fabricating permeable polymer microstructure barriers in polydimethylsiloxane (PDMS) microfluidic devices and the use of the devices to capture and transport DNA and cells. The polymer microstructure in a desired location in a fluidic channel is formed in situ by the polymerization of acrylamide and polyethylene diacrylate cross-linker (PEG-DA) monomer in a solution which is trapped in the location using a pair of PDMS valves. The porous polymer microstructure provides a mechanical barrier to convective fluid flow in the channel or between two microfluidic chambers while it still conducts ions or small charged species under an electric field, allowing for the rapid capture and transport of biomolecules and cells by electrophoresis. We have demonstrated the application of the devices for the rapid capture and efficient release of bacteriophage λ genomic DNA, solution exchange and for the transport and capture of HeLa cells. Our devices will enable the multi-step processing of biomolecules and cells or individual cells within a single microfluidic chamber.

This study compares the accuracy of eyewitness accounts provided by police cadets and civilians in Korea. Participants were 50 male cadets from a police college, and 100 male and 104 female civilian college students who watched a videotaped enactment of a robbery. The next day, they were asked to identify the perpetrator who was photographed in different angles and outfits together with 40 photographs of other individuals. Analyses within the framework of signal detection theory suggest that the major difference between the police and the civilian groups was in their perceptual sensitivity rather than in their judgmental criteria, with the police cadets being inferior to the civilians in perceptual sensitivity. However, a strong positive correlation was found between the observed sensitivity index and the observed criterion index. Results suggested that (1) visually monotonous social environments may decrease perceptual sensitivity in the identification of people, (2) police cadets are no better at avoiding false negative errors, i.e., mistakenly identifying the true suspect as an innocent, than civilian college students, and (3) perceptual sensitivity in the identification of people is strongly related to judgmental criteria, presumably because personal emphasis is on individuality.

Histone-modifying enzymes play a pivotal role in gene expression and repression. In human, DOT1L (Dot1-like) is the only known histone H3 lysine 79 methyltransferase. hDOT1L is associated with transcriptional activation, but the general mechanism connecting hDOT1L to active transcription remains largely unknown. Here, we report that hDOT1L interacts with the phosphorylated C-terminal domain of actively transcribing RNA polymerase II (RNAPII) through a region conserved uniquely in multicellular DOT1 proteins. Genome-wide profiling analyses indicate that the occupancy of hDOT1L largely overlaps with that of RNAPII at actively transcribed genes, especially surrounding transcriptional start sites, in embryonic carcinoma NCCIT cells. We also find that C-terminal domain binding or H3K79 methylations by hDOT1L is important for the expression of target genes such as NANOG and OCT4 and a marker for pluripotency in NCCIT cells. Our results indicate that a functional interaction between hDOT1L and RNAPII targets hDOT1L and subsequent H3K79 methylations to actively transcribed genes.

A new functionalized triethoxysilane bearing an X-shaped, anthracene-based semiconducting molecule on one arm was designed and synthesized as a precursor for the preparation of a self-assembled monolayer (SAM) on a SiO(2) substrate. 3-Isocyanatopropyl triethoxysilane was reacted with a monohydroxyl-terminated X-shaped, anthracene-based semiconducting molecule in the presence of tin catalyst. The 6-(5-((6-((5-hexylthiophen-2-yl)ethynyl)-9,10-bis(phenylethynyl)anthracen-2-yl)ethynyl)thiophen-2-yl)hexyl 3-(triethoxysilyl)propylcarbamate (BATHT-TEOS) was found to be stable and sufficiently reactive to form organic monolayers on hydroxylated SiO(2) surfaces. The structures and properties of these SAMs were investigated using X-ray photoelectron spectroscopy, UV-vis absorption spectroscopy, photoluminescence (PL) spectroscopy, laser scanning confocal microscopy-PL spectrometry, and spectroscopic ellipsometry. In this work, BATHT-SAM was employed as an interfacial layer on SiO(2) to fabricate ultrathin film transistors (UTFTs, active layer thickness ∼ 16.09 nm). The device UTFT-I, made of 0.06 wt % 5,5'-(9,10-bis(phenylethynyl)anthracene-2,6-diyl)bis(ethyne-2,1-diyl)bis(2-hexylthiophene) (BATHT) solution on an n-octyltrichlorosilane-SAM/SiO(2) layer, showed no gate effect for the carrier transport behavior; however, the device UTFT-II, fabricated on BATHT-SAM/SiO(2), exhibited field effect mobilities of 0.04 cm(2) V(-1) s(-1) (I(on/off) ∼ 6.3 × 10(3) to 1.0 × 10(4)). This can be attributed to the effect of BATHT-SAM inducing uniform coverage and ordering of BATHT molecules as an upper layer.

There is an increasing need to develop optofluidic flow cytometers. Optofluidics, where optics and microfluidics work together to create novel functionalities on a small chip, holds great promise for lab-on-a-chip flow cytometry. The development of a low-cost, compact, handheld flow cytometer and microfluorescence-activated cell sorter system could have a significant impact on the field of point-of-care diagnostics, improving health care in, for example, underserved areas of Africa and Asia, that struggle with epidemics such as HIV∕AIDS. In this paper, we review recent advancements in microfluidics, on-chip optics, novel detection architectures, and integrated sorting mechanisms.

We present a novel method to fabricate photonic crystal for visible light control and demonstrate high resolution patterning of multiple structural colors using a single material. The material, termed as "M-Ink", whose color is magnetically tunable and lithographically fixable, is developed. By combining novel material system and specially designed instrument, we produce patterns with arbitrary spatial arrangements of colors with single material.

We demonstrate the microfluidic sorting of directionally oriented (anisotropic) microstructures by their orientational state in solution using the concept of railed microfluidics. After being injected into a microfluidic channel, the microstructures rotate and flip in various directions. In order to sort microstructures in an organized way, we designed the microstructures and the microchannel to allow for orientation-based control of microstructure movement. In order to sort microstructures based on their rotation, we used a wedge shaped fin on the microstructures and a Y-shaped railed microfluidic channel. For sorting flipped particles, we use a double-railed microfluidic channel that has grooves on both its top and bottom surfaces. By integrating the two sorting methods we demonstrated high throughput, autonomous sorting into four different orientational states: unrotated-unflipped, rotated-unflipped, unrotated-flipped, and rotated-flipped. Here we not only demonstrate orientational assembly of directionally dependent microstructures, but also present design considerations for future work.

This article presents free-floating three-dimensional (3D) microstructure fabrication in a microfluidic channel using direct fine-tuned grayscale image lithography. The image is designed as a freeform shape and is composed of gray shades as light-absorbing features. Gray shade levels are modulated through multiple reflections of light in a digital micromirror device (DMD) to produce different height formations. Whereas conventional photolithography has several limitations in producing grayscale colors on photomask features, our method focuses on a maskless, single-shot process for fabrication of freeform 3D micro-scale shapes. The fine-tuned gray image is designed using an 8-bit grayscale color; thus, each pixel is capable of displaying 256 gray shades. The pattern of the UV light reflecting on the DMD is transferred to a photocurable resin flowing through a microfluidic channel. Here, we demonstrate diverse free-floating 3D microstructure fabrication using fine-tuned grayscale image lithography. Additionally, we produce polymeric microstructures with locally embedded gray encoding patterns, such as grayscale-encoded microtags. This functional microstructure can be applied to a biophysical detection system combined with 3D microstructures. This method would be suitable for fabricating 3D microstructures that have a specific morphology to be used for particular biological or medical applications.

We investigated the effect of nitrogen (N) doping on the threshold voltage of an ovonic threshold switching device using amorphous GeSe. Using the spectroscopic ellipsometry, we found that the addition of N brought about significant changes in electronic structure of GeSe, such as the density of localized states and the band gap energy. Besides, it was observed that the characteristics of OTS devices strongly depended on the doping of N, which could be attributed to those changes in electronic structure suggesting a method to modulate the threshold voltage of the device.

Cu thin films sandwiched between Nb-doped TiO2 (NTO) thin films were grown on glass substrates using tilted-dual target DC magnetron sputtering deposition. The thicknesses of the top and bottom NTOs were nominally 30 nm, and the thicknesses of the Cu films (t) varied between 1.5 nm and 50 nm. We measured the ellipsometric angles (Ψ,Δ) of the NTO/Cu/NTO/glass by using spectroscopic ellipsometry and estimated the thicknesses and dielectric functions of the Cu films by using a multi-layer model analysis. Transmission electron microscopy measurements showed that the Cu layers evolved from aggregates of Cu nanoparticles to coalesced Cu thin films as the Cu film thickness increased. Sheet resistance data also showed that the t = 8 nm film was near the percolation threshold, suggesting that films thinner than 8 nm were aggregations of Cu nanoparticles that were not well-connected. The films thicker than 8 nm were above the percolation threshold. From the Drude model, we estimated the plasmon frequency (ωp) and the electron relaxation time (τ), which were found to increase with increasing film thickness. By applying standard critical point analysis to the second derivatives of the dielectric function spectra, we found several peaks near 1.5, 2.1, 2.5, 3.5, and 4.3 eV, and attributed to interband transitions. The peak energies (except 1.5 eV) matched to the band structure calculations of bulk Cu found in the literature.