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Daman Landslide had blocked one of the three cross-island roads in Taiwan, and a road section has been under control since last October. During the period, more than thousands of small-scale post-failures occurred whose irregular patterns affected the safety of engineering workers for slope protection construction and road users. Therefore, we installed one time-lapse camera and two geophones at the crown and closed to the toe of the Daman landslide, respectively to train a classification model to offer in-situ alarm. According to time-lapse photos, those post failures can be categorized into two types. One is rock/debris moving and stopping above the upper slope or road, named type I, and the other is the rock/debris going through the road to download slope, named type II. Type I was almost recorded by the crown station, and type II was shown by both stations with different arrival times and the toe station’ high-frequency signals gradually rising (up to 100 Hz). Those distinct features were exhibited by spectrograms. To keep characteristics simultaneously, we merge two stations’ spectrograms as one to indicate different types of post-failures. However, frequent earthquakes affect the performance of the landslide’s discrimination, which should be involved in the classification model. A total of three labels, type I, type II, and earthquake, contained more than 15,000 images of spectrogram, have been used for deep neural network (DNN) to be a two-station-based automatic classifier. Further, user-defined parameters for the specific frequency band within fixed time span windows, including a sum of power spectrogram density, the arrival time of peak amplitude, cross-correlation coefficient, and signal-to-noise ratio, have been utilized for the decision tree algorithm. Both model results benefit the automatic classifier for post-failure alarms and can readily extend to monitor other landslides with frequent post-failures by transfer learning.

Rock slope instability, such as rockslides and rock falls, are common issues along mountain highways. These natural phenomena not only control the slope morphology but also pose substantial risk to the safety of road users. When highway authority responds to those disasters, the first task is to estimate the landslide volume and potential sliding volume for planning emergency measures. Recent advances in UAV-based 3D point cloud analyses have improved our ability to investigate landslides efficiency with unprecedented time resolution. However, different techniques involve several limitations that should be considered when approaching landslide volume estimation for progressive rockslides. This study demonstrates how the effects of multitemporal point cloud dataset alignment may hinder the analysis of landslide development in high steep highway slope. A specific progressive rockslide occurred in Northern Cross-Island Highway of Taiwan is discussed. The landslide initiated on 14 September 2022 after Typhoon Muifa leave Taiwan. The first disaster caused the road to be blocked at the mileage of 49.8K for two days and developed continually for the next one month. We obtained pre- and post-disaster UAV-based point cloud data for three major disasters during the period. The DEMs of Difference (DoD) and Iterative Closest Point (ICP) approaches were used to minimize the positioning error and estimate the landslide volume for each event. In addition, the feasibility of another common approach multiscale model-to-model cloud comparison (M3C2) was also discussed. The study provides authorities and practitioners with qualitative comparison regarding the application of UAV-based 3D point cloud analyses on landslide volume estimation for progressive rockslides. The results also benefit scientists in developing scenario modeling based on numerical simulation.

Mega-earthquakes and extreme climate events accompanied by intrinsic fragile geology lead to numerous landslides along mountain highways in Taiwan, causing enormous life and economic losses. In this study, a system for rapid slope disaster information integration and assessment is proposed with the aim of providing information on landslide occurrence, failure mechanisms, and subsequent landslide-affected areas to the highway authority rapidly. The functionality of the proposed system is deployed into three units: (1) geohazard rapid report (GeoPORT I), (2) multidisciplinary geological survey report (GeoPORT II), and (3) site-specific landslide simulation report (GeoPORT III). After landslide occurrence, the seismology-based monitoring network rapidly provides the initial slope disaster information, including preliminary location, event magnitude, earthquake activity, and source dynamics, within an hour. Within 3 days of the landslide, a multidisciplinary geological survey is conducted to collect high-precision topographical, geological, and remote-sensing data to determine the possible failure mechanism. After integrating the aforementioned information, a full-scale three-dimensional landslide simulation based on the discrete element method is performed within 10 days to reveal the failure process and to identify the areas potentially affected by subsequent disasters through scenario modeling. Overall, the proposed system can promptly provide comprehensive and objective information to relevant authorities after the event occurrence for hazard assessment. The proposed system was validated using a landslide event in the Central Cross-Island Highway of Taiwan.

Deciphering signaling mechanisms critical for the extended pluripotent stem cell (EPSC) state and primed pluripotency is necessary for understanding embryonic development. Here, a membrane protein, podocalyxin-like protein 1 (PODXL) as being essential for extended and primed pluripotency, is identified. Alteration of PODXL expression levels affects self-renewal, protein expression of c-MYC and telomerase, and induced pluripotent stem cell (iPSC) and EPSC colony formation. PODXL is the first membrane protein reported to regulate de novo cholesterol biosynthesis, and human pluripotent stem cells (hPSCs) are more sensitive to cholesterol depletion than fibroblasts. The addition of exogenous cholesterol fully restores PODXL knockdown-mediated loss of pluripotency. PODXL affects lipid raft dynamics via the regulation of cholesterol. PODXL recruits the RAC1/CDC42/actin network to regulate SREBP1 and SREBP2 maturation and lipid raft dynamics. Single-cell RNA sequencing reveals PODXL overexpression enhanced chimerism between human cells in mouse host embryos (hEPSCs 57%). Interestingly, in the human-mouse chimeras, laminin and collagen signaling-related pathways are dominant in PODXL overexpressing cells. It is concluded that cholesterol regulation via PODXL signaling is critical for ESC/EPSC.

We systematically studied the temporal profile of biphotons, i.e., pairs of time-correlated single photons, generated from a hot atomic vapor via the spontaneous four-wave mixing process. The measured temporal width of biphoton wave packet or two-photon correlation function against the coupling power was varied from about 70 to 580 ns. We derived an analytical expression of the biphoton's spectral profile in the Doppler-broadened medium. The analytical expression reveals that the spectral profile is mainly determined by the effect of electromagnetically induced transparency (EIT), and behaves like a Lorentzian function with a linewidth approximately equal to the EIT linewidth. Consequently, the biphoton's temporal profile influenced by the Doppler broadening is an exponential-decay function, which was consistent with the experimental data. Employing a weak input probe field of classical light, we further measured the EIT spectra under the same experimental conditions as those in the biphoton measurements. The theoretical predictions of the biphoton wave packets calculated with the parameters determined by the classical-light EIT spectra are consistent with the experimental data. The consistency demonstrates that in the Doppler-broadened medium, the classical-light EIT spectrum is a good indicator for the biphoton's temporal profile. Besides, the measured biphoton's temporal widths well approximated to the predictions of the analytical formula based on the biphoton's EIT effect. This study provides an analytical way to quantitatively understand the biphoton's spectral and temporal profiles in the Doppler-broadened medium.

Psychiatric disorders are a collection of heterogeneous mental disorders arising from a contribution of genetic and environmental insults, many of which molecularly converge on transcriptional dysregulation, resulting in altered synaptic functions. The underlying mechanisms linking the genetic lesion and functional phenotypes remain largely unknown. Patient iPSC-derived neurons with a rare frame-shift DISC1 (Disrupted-in-schizophrenia 1) mutation have previously been shown to exhibit aberrant gene expression and deficits in synaptic functions. How DISC1 regulates gene expression is largely unknown. Here we show that activating transcription factor 4 (ATF4), a DISC1 binding partner, is more abundant in the nucleus of DISC1 mutant human neurons and exhibits enhanced binding to a collection of dysregulated genes. Functionally, overexpressing ATF4 in control neurons recapitulates deficits seen in DISC1 mutant neurons, whereas transcriptional and synaptic deficits are rescued in DISC1 mutant neurons with CRISPR-mediated heterozygous ATF4 knockout. By solving the high-resolution atomic structure of the DISC1-ATF4 complex, we show that mechanistically, the mutation of DISC1 disrupts normal DISC1-ATF4 interaction, and results in excessive ATF4 binding to DNA targets and deregulated gene expression. Together, our study identifies the molecular and structural basis of an DISC1-ATF4 interaction underlying transcriptional and synaptic dysregulation in an iPSC model of mental disorders.

We reveal by high-throughput screening that activating transcription factor 1 (ATF1) is a novel pluripotent regulator in human embryonic stem cells (hESCs). The knockdown of ATF1 expression significantly up-regulated neuroectoderm (NE) genes but not mesoderm, endoderm, and trophectoderm genes. Of note, down-regulation or knockout of ATF1 with short hairpin RNA (shRNA), small interfering RNA (siRNA), or clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) was sufficient to up-regulate sex-determining region Y-box (SOX)2 and paired box 6 (PAX6) expression under the undifferentiated or differentiated conditions, whereas overexpression of ATF1 suppressed NE differentiation. Endogenous ATF1 was spontaneously down-regulated after d 1–3 of neural induction. By double-knockdown experiments, up-regulation of SOX2 was critical for the increase of PAX6 and SOX1 expression in shRNA targeting Atf1 hESCs. Using the luciferase reporter assay, we identified ATF1 as a negative transcriptional regulator of Sox2 gene expression. A novel function of ATF1 was discovered, and these findings contribute to a broader understanding of the very first steps in regulating NE differentiation in hESCs.—Yang, S.-C., Liu, J.-J., Wang, C.-K., Lin, Y.-T., Tsai, S.-Y., Chen, W.-J., Huang, W.-K., Tu, P.-W. A., Lin, Y.-C., Chang, C.-F., Cheng, C.-L., Lin, H., Lai, C.-Y., Lin, C.-Y., Lee, Y.-H., Chiu, Y.-C., Hsu, C.-C., Hsu, S.-C., Hsiao, M., Schuyler, S. C., Lu, F. L., Lu, J. Down-regulation of ATF1 leads to early neuroectoderm differentiation of human embryonic stem cells by increasing the expression level of SOX2.

Landslide, debris flow, and debris flood are the most common geological hazards triggered by intense rainfall in Taiwan. Taiwan is a very densely populated high relief island, and therefore the landslides sometimes affect our transportation and energy infrastructures and populated areas. This study investigates the regional landslide activity and potential slope movement using high-resolution time-series RADARSAT-2 InSAR images. We focussed on the 2015 typhoon, which affected Wulai and Xindian Districts in northern Taiwan. InSAR techniques, such as D-InSAR and SBAS, were applied to detect slope deformation caused by shallow and deep-seated landslides. This study conducted field investigations, and used high-resolution DTMs, and 3D photographic UAV surveying to determine the landslide hotspots and geomorphologic changes. The validation results show the InSAR maps accurately identify slow-moving landslides with a surface displacement of about 2 cm/year and debris flows on the bed of a gully. The InSAR displacement map helps to recognize the possible deep-seated landslides not previously known using a DTM. The field validation of the InSAR results from the proposed approach confirmed that the detection of different types of slope-land hazards: shallow landslides, deep-seated landslides, debris flows, and sediment deposition. Furthermore, the result will contribute to updating the national-wide environmental geologic map and provide competent authority to make decisions reducing the geohazard risk.

Neurological complications are common in patients with COVID-19. While SARS-CoV-2, the causal pathogen of COVID-19, has been detected in some patient brains, its ability to infect brain cells and impact their function are not well understood. Here we investigated the susceptibility of human induced pluripotent stem cell (hiPSC)-derived monolayer brain cells and region-specific brain organoids to SARS-CoV-2 infection. We found that neurons and astrocytes were sparsely infected, but choroid plexus epithelial cells underwent robust infection. We optimized a protocol to generate choroid plexus organoids from hiPSCs and showed that productive SARS-CoV-2 infection of these organoids is associated with increased cell death and transcriptional dysregulation indicative of an inflammatory response and cellular function deficits. Together, our findings provide evidence for selective SARS-CoV-2 neurotropism and support the use of hiPSC-derived brain organoids as a platform to investigate SARS-CoV-2 infection susceptibility of brain cells, mechanisms of virus-induced brain dysfunction, and treatment strategies., Graphical Abstract, HIGHLIGHTS • SARS-CoV-2 minimally infects human neurons and astrocytes in 2D and brain organoids • Model developed for hiPSC-derived choroid plexus organoids (CPOs) • SARS-CoV-2 productively infects CPOs and increases cell death • SARS-CoV-2 CPO infection leads to transcriptional upregulation of inflammatory genes, SARS-CoV-2 causes neurological symptoms in a significant portion of patients with COVID-19. Ming and colleagues tested SARS-CoV-2 neurotropism using monolayer neural cells and brain organoids generated from human pluripotent stem cells and show minimal neuron and astrocyte infection, but efficient choroid plexus infection, leading to cell death and functional deficits.

SUMMARYNeurological complications are common in patients with COVID-19. While SARS-CoV-2, the causal pathogen of COVID-19, has been detected in some patient brains, its ability to infect brain cells and impact their function are not well understood, and experimental models using human brain cells are urgently needed. Here we investigated the susceptibility of human induced pluripotent stem cell (hiPSC)-derived monolayer brain cells and region-specific brain organoids to SARS-CoV-2 infection. We found modest numbers of infected neurons and astrocytes, but greater infection of choroid plexus epithelial cells. We optimized a protocol to generate choroid plexus organoids from hiPSCs, which revealed productive SARS-CoV-2 infection that leads to increased cell death and transcriptional dysregulation indicative of an inflammatory response and cellular function deficits. Together, our results provide evidence for SARS-CoV-2 neurotropism and support use of hiPSC-derived brain organoids as a platform to investigate the cellular susceptibility, disease mechanisms, and treatment strategies for SARS-CoV-2 infection.

Typhoons Megi (2010) and Saola (2012) brought torrential rainfall which triggered regional landslides and flooding hazards along Provincial Highway No. 9 in northeastern Taiwan. To reduce property loss and saving lives, this study combines multi-hazard susceptibility assessment with environmental geology map a rock mass rating system (RMR), remote sensing analysis, and micro-topography interpretation to develop an integrated landslide hazard assessment approach and reflect the intrinsic state of slopeland from the past toward the future. First, the degree of hazard as indicated by historical landslides was used to determine many landslide regions in the past. Secondly, geo-mechanical classification of rock outcroppings was performed by in-situ investigation along the vulnerable road sections. Finally, a high-resolution digital elevation model was extracted from airborne LiDAR and multi-temporal remote sensing images which was analyzed to discover possible catastrophic landslide hotspot shortly. The results of the analysis showed that 37% of the road sections in the study area were highly susceptible to landslide hazards. The spatial distribution of the road sections revealed that those characterized by high susceptibility were located near the boundaries of fault zones and in areas of lithologic dissimilarity. Headward erosion of gullies and concave-shaped topographic features had an adverse effect and was the dominant factor triggering landslides. Regional landslide reactivation on this coastal highway are almost related to the past landslide region based on hazard statistics. The final results of field validation demonstrated that an accuracy of 91% could be achieved for forecasting geohazard followed by intense rainfall events and typhoons.

Human brain organoids represent remarkable platforms for recapitulating features of human brain development and diseases. Existing organoid models do not resolve fine brain subregions, such as different nuclei in the hypothalamus. We report the generation of arcuate organoids (ARCOs) from human induced pluripotent stem cells (iPSCs) to model the development of the human hypothalamic arcuate nucleus. Single-cell RNA sequencing of ARCOs revealed significant molecular heterogeneity underlying different arcuate cell types, and machine learning-aided analysis based on the neonatal human hypothalamus single-nucleus transcriptome further showed a human arcuate nucleus molecular signature. We also explored ARCOs generated from Prader-Willi syndrome (PWS) patient iPSCs. These organoids exhibit aberrant differentiation and transcriptomic dysregulation similar to postnatal hypothalamus of PWS patients, indicative of cellular differentiation deficits and exacerbated inflammatory responses. Thus, patient iPSC-derived ARCOs represent a promising experimental model for investigating nucleus-specific features and disease-relevant mechanisms during early human arcuate development.

Copper(I) N-heterocyclic carbene has a good activity towards aryl halides and was used as a model complex to study the catalytic cycle of Cu(I) to catalyze the cross C–S coupling reaction because the N-heterocyclic carbene has a strong electron donating property, and ligand dissociation can be avoided. Free radical scavenger cumene does not retard the yield of the reaction indicating that the catalytic reaction goes through a non free radical path. Switching the solvent from toluene to DMF lowered the yield of the reaction. DFT calculation shows that the activation of aryl halide is the rate determining step, and the activation energy is higher for the reaction in DMF than in toluene. A plausible catalytic cycle is proposed with the support of DFT calculation.

Genome-wide mapping of chromatin interactions at high resolution remains experimentally and computationally challenging. Here we used a low-input “easy Hi-C” (eHi-C) protocol to map the 3D genome architecture in neurogenesis and brain tissues, and also developed an improved Hi-C bias-correction pipeline (HiCorr) enabling better identification of enhancer loops or aggregates at sub-TAD level. We compared ultra-deep 3D genome maps from 10 human tissue- or cell types, with a focus on stem cells and neural development. We found several large loci in skin-derived human iPSC lines showing recurrent 3D compartmental memory of somatic heterochromatin. Chromatin loop interactions, but not genome compartments, are hallmarks of neural differentiation. Interestingly, we observed many cell type- or differentiation-specific enhancer aggregates spanning large neighborhoods, supporting a phase-separation mechanism that stabilizes enhancer contacts during development. Finally, we demonstrated that chromatin loop outperforms eQTL in explaining neurological GWAS results, revealing a unique value of high-resolution 3D genome maps in elucidating the disease etiology.HighlightsLow input “easy Hi-C” protocol compatible with 50-100K cellsImproved Hi-C bias correction allows direct observation and accurate identification of sub-TAD chromatin loops and enhancer aggregatesRecurrent architectural memory of somatic heterochromatin at compartment level in skin-derived hiPSCsChromatin loop, but not genome compartment, marks neural differentiationChromatin loop outperforms eQTL in defining brain GWAS target genes

Two new donor–π-bridge–acceptor zinc porphyrins with dimethylaminonaphthalene electron donating moieties, coded T1 and T2, were synthesized and used as sensitizers in dye sensitized solar cells (DSSCs). Both dyes showed excellent photovoltaic properties with power conversion efficiencies of 8.0 and 9.6% for T1 and T2 respectively, for which the device performance of T2 dye is superior to that of N719 dye.

Genome-wide mapping of chromatin interactions at high-resolution remains experimentally and computationally challenging. Here we used a low-input “easy Hi-C” protocol to map the 3D genome architecture in human neurogenesis and brain tissues, and also demonstrated that a rigorous Hi-C bias-correction pipeline (HiCorr) can significantly improve the sensitivity and robustness of Hi-C loop identification at sub-TAD level, especially the enhancer-promoter (E-P) interactions. We used HiCorr to compare the high-resolution maps of chromatin interactions from 10 tissue- or cell-types with a focus on neurogenesis and brain tissues. We found that dynamic chromatin loops are better hallmarks for cellular differentiation than compartment switching. HiCorr allowed direct observation of cell type- and differentiation-specific E-P aggregates spanning large neighborhoods, suggesting a mechanism that stabilizes enhancer contacts during development. Interestingly, we concluded that Hi-C loop outperforms eQTL in explaining neurological GWAS results, revealing a unique value of high-resolution 3D genome maps in elucidating the disease etiology.

Plasminogen (Plg) and thrombomodulin (TM) are glycoproteins well known for fibrinolytic and anticoagulant functions, respectively. Both Plg and TM are essential for wound healing. However, their significance during the reparative process was separately demonstrated in previous studies. Here, we investigate the interaction between Plg and epithelial TM and its effect on wound healing. Characterization of the wound margin revealed that Plg and TM were simultaneously upregulated at the early stage of wound healing and the two molecules were bound together. In vitro, TM silencing or knockout in keratinocytes inhibited Plg activation. Plg treatment enhanced keratinocyte proliferation and migration, and these actions were abolished by TM antibody. Keratinocyte-expressed vascular endothelial growth factor (VEGF), which presented a dose-response relationship with Plg treatment, can be suppressed by TM silencing. Moreover, treatment with VEGF antibody inhibited Plg-enhanced keratinocyte proliferation and wound recovery. In vivo, TM antibody treatment and keratinocyte-specific TM knockout can impede Plg-enhanced wound healing in mice. In high-glucose environments, Plg-enhanced VEGF expression and wound healing were suppressed due at least in part to downregulation of keratinocyte-expressed TM. Taken together, our findings suggest that activation of Plg/TM signaling may hold therapeutic potential for chronic wounds in diabetic or non-diabetic individuals. KEY MESSAGES: Plg binds to TM in cutaneous wound healing. TM facilitates the activation of Plg to Plm in keratinocytes. Epithelial TM regulates Plg-enhanced wound healing through VEGF expression.

Using heat sink to increase the cooling area is the most familiar and fundamental method in LED heat management technology. We develop a new configuration of finned heat sink for LED lamp. It is a circular cylinder with many plate fins radially arranged on the external surface. There are many straight ducts inside the peripheral wall of the cylinder. These ducts form the chimney effect to enhance the heat transfer. This work experimentally investigated the chimney effect on the heat transfer characteristics of the finned heat sink under the free convection state. The aluminum-alloy plate spreader with two vertical plate fins was selected as the control group. The experimental group was the heat sink having the same configuration of the control group but had a vertical passage within the spreader. The results show that the vertical passage did strengthen 8.3~12.1% free convection performance for the present test heat sink.

On August 31st, 2013, high intensity rainfall caused a severe rockfall disaster in Badouzih, Keelung. This study combines the results of detailed field investigation and process-based as well as empirical-based method to point out unsafe road sections. The mechanisms and the characteristics of motions of rockfall are analyzed in the field. Two intersecting joints and the bedding plane divided bedrock into blocks. Weathering and the infiltration of rainfall accelerated the erosion process and precipitated ruptures. When the rainfall reached its highest intensity which is 94.5 mm/h in this event, a great deal of water on the slope surface eroded the matrix, causing instability and leading to the failure of the rock blocks. The process of rockfall took 23 s and can be divisible into 4 stages including roll, fall, bounce, and roll. Process-based simulations are adopted in this case and several critical road sections to understand the characteristic of movements. With the empirical-based energy line angle analysis, potential road sections which may affect by rockfall are showed and their energy are also estimated for the purpose of mitigating rockfall impact, reducing similar disasters in this area.

Open image in new window A Central Geologic Survey investigation of large-scale landslides in the southern part of Taiwan identified a new, large-scale landslide in the Xinzhuang Village of Shanlin District, Kaohsiung City (ID: Kaohsiung-Shanlin-D021) which has the potential to influence the safety of residents. In order to reduce landslide hazard, this study assesses the potential for the landslide to fail. Field data, including the results of borehole sampling and laboratory experiments, is collected and analyzed and used to estimate the extent of the failure zone. We consider the effect of hydrogeological conditions, construct a conceptual model of subsurface conditions and analyze the stability of the landslide. After completing a comprehensive analysis of the Xinzhuang landslide, the landslide was divided into three potential failure masses (Zone 1, Zone 2 and Zone 3). Results of the analysis demonstrate that the safety factor of the Zone 3 is the lowest. Analysis results show that once precipitation causes the water table to near the bottom of the colluvium, the potential failure block may become unstable. Additionally, the impact of failure on the Xinzhuang Village is evaluated. If the Zone 3 potential sliding mass does mobilize, the main area affected by the deposit is the area southeast of Highway 29 (Sima road), Alley 106 and Alley 58. People living in this area are at risk of being buried by 1–20 m of landslide debris. The methods applied in this study can be applied to other villages and used as a reference for the development of disaster prevention and evacuation planning.

By means of femtosecond infrared transient absorption spectra, we measured the interfacial electron-transfer dynamics for benzimidazole-based heteroleptic ruthenium dyes (RD5, RD12, RD15−RD18) sensitized on TiO2 thin films. For all measurements, the first singlet metal-to-ligand charge-transfer states ( 1 MLCT) of the ruthenium complexes were excited at 519 nm and the injected electrons in the conduction band of TiO2 were probed at 4.3 μm. All transient signals featured two rising components on a femtosecond−picosecond scale due to a two-step electron injection and an offset (N719, RD16−RD18) or a slow-decay (RD5, RD12, and RD15) component on a nanosecond−microsecond scale due to a back electron transfer. A complicated two-step kinetic model was derived analytically to interpret the observed two rising components for which the rapid (τ1 < 300 fs) and slow (τ2 =1 0−20 ps) electron injections arose from the singlet 1 MLCT and triplet 3 MLCT states, respectively. The amplitudes of the two electron-injection components (A1 and A2) were controlled by the rate coefficient of the 1 MLCT → 3 MLCT intersystem crossing; the variations of A1 and A2 are consistent with the trend of the corresponding Stokes shifts rationalized with a conventional energy-gap law for nonradiative transitions. Compared with the kinetics observed for the N719 dye, the involvement of a benzimidazole ligand in RD dyes had the effect of accelerating the two electron injections, thus improving the short circuit current of the device. RD dyes substituted with fluorine atoms and/or thiophene units in the benzimidazole ligands showed a retardation of 3 MLCT electron injection relative to that of the nonsubstituted RD5 dye. Acceleration of the BET process was observed for the RD5 dye (9 ns), and both fluoro-substituted dyes (14 ns for RD12 and 21 ns for RD15) and thiophene-substituted dyes (nonobservable for RD16−RD18) had significantly retarded BET kinetics. The observed kinetics of the 3 MLCT electron injection for all RD dyes is satisfactorily simulated with the Marcus theory.

Copper-catalyzed alkene oxidation to carbonyl compounds by tert-butyl hydroperoxide (TBHP) under organic solvent-free and biphasic conditions at room temperature is selective for the aromatic gem-disubstituted alkenes. Enhanced reactivity was observed in the presence of 2,9-dimethyl-1,10-phenanthroline (neocuproine). The reaction is economically attractive because the yield is high, and separation of products and recycling of the catalyst are easy.

On September 15, 2012, torrential rains carried by the peripheral circulation of Typhoon Sanba and the northeast monsoon induced a translational landslide near Pingguang Road in Xindian District of New Taipei City, Taiwan. The total volume of the landslide was ~162,000 m3. The sliding mass destroyed two houses across the stream and formed a landslide dam at the toe of the slope, constricting the stream. For the purpose of reducing sediment-relative hazard around mountainous area, the paper attempts to explore the dynamics and phenomenon of the landslide on dip slope. This study interpreted remote sensing images and terrestrial LiDAR scanning, conducted onsite surveys to obtain material parameters, and performed simulations using the discrete element method to reconstruction the post-event, in order to elucidate the mechanisms involved in the landslide process. Survey results revealed complex geological conditions with tension cracks spreading in all directions at source area. This facilitated the infiltration of surface runoff into weak surfaces and raised groundwater levels. Slope failure may occur along the stratum boundary once the intrinsic shear strength of regolith drops below a critical value. The results of numerical simulation reveal that at 80 s after the Pingguang stream landslide began, a maximum deposition depth of 20 m had been reached. The sliding mass cut off the stream and pushed the stream flow roughly 35 m to the southeast. Because the slope materials surrounding the study area and the landslide-inducing mechanisms are similar, the top of the slopes to the northwest of the study area requires close monitoring. Finally, a detailed potential landslide mapping and interpretation from the high-resolution digital elevation model also present to prevent further landslides. The investigation indicates that the occurrence of landslide is highly related to seepage effect of accumulated rainfall, toe erosion by surface runoff, and local unstable geological structure.

A simple strategy to fabricate flexible dye-sensitized solar cells involves the use of photoanodes based on TiO2 nanotube (TNT) arrays with rear illumination. The TNT films (tube length ∼35 μm) were produced via anodization, and sensitized with N719 dye for photovoltaic characterization. Pt counter electrodes of two types were used: a conventional FTO/glass substrate for a device of rigid type and an ITO/PEN substrate for a device of flexible type. These DSSC devices were fabricated into either a single-cell structure (active area 3.6×0.5 cm2) or a parallel module containing three single cells (total active area 5.4 cm2). The flexible devices exhibit remarkable performance with efficiencies η=5.40% (single cell) and 4.77% (parallel module) of power conversion, which outperformed their rigid counterparts with η=4.87% (single cell) and 4.50% (parallel model) under standard one-sun irradiation. The flexible device had a greater efficiency of conversion of incident photons to current and a broader spectral range than the rigid device; a thinner electrolyte layer for the flexible device than for the rigid device is a key factor to improve the light-harvesting ability for the TNT-DSSC device with rear illumination. Measurements of electrochemical impedance spectra show excellent catalytic activity and superior diffusion characteristics for the flexible device. This technique thus provides a new option to construct flexible photovoltaic devices with large-scale, light-weight, and cost-effective advantages for imminent applications in consumer electronics.

To construct a hybrid titania photoanode containing nanoparticles and nanorods of varied size in a multilayer (ML) configuration for dye-sensitized solar cells, the essence of our ML design is a bilayer system with additional layers of nanorods of well-controlled size inserted between the transparent and the scattering layers to enhance the light-harvesting capability for photosensitizers with small absorptivity, such as Z907. We measured charge-extraction and intensity-modulated photoelectric spectra to show the advantages of one-dimensional nanorods with an improved electron-transport property and an upward shift of the potential band edge; a favorable ML configuration was constructed to have a cascade potential feature for feasible electron transport from long nanorods, to normal nanorods, to small nanoparticles. On the basis of the ML system reported herein, we demonstrate how the performance of a Z907 device is improved to attain η ∼10%, which is a milestone for its future commercialization.

A simple hydrothermal method with titanium tetraisopropoxide (TTIP) as a precursor and triethanolamine (TEOA) as a chelating agent enabled growth in the presence of a base (diethylamine, DEA) of anatase titania nanocrystals (HD1-HD5) of controlled size. DEA played a key role to expedite this growth, for which a biphasic crystal growth mechanism is proposed. The produced single crystals of titania show octahedron-like morphology with sizes in a broad range of 30-400 nm; a typical, extra large, octahedral single crystal (HD5) of length 410 nm and width 260 nm was obtained after repeating a sequential hydrothermal treatment using HD3 and then HD4 as a seed crystal. The nanocrystals of size ~30 nm (HD1) and ~300 nm (HD5) served as active layer and scattering layer, respectively, to fabricate N719-sensitized solar cells. These HD devices showed greater V(OC) than devices of conventional nanoparticle (NP) type; the overall device performance of HD attained an efficiency of 10.2% power conversion at a total film thickness of 28 μm, which is superior to that of a NP-based reference device (η = 9.6%) optimized at a total film thickness of 18-20 μm. According to results obtained from transient photoelectric and charge extraction measurements, this superior performance of HD devices relative to their NP counterparts is due to the more rapid electron transport and greater TiO(2) potential.

Zika virus (ZIKV) infection causes microcephaly and has been linked to other brain abnormalities. How ZIKV impairs brain development and function is unclear. Here we systematically profiled transcriptomes of human neural progenitor cells exposed to Asian ZIKVC, African ZIKVM, and dengue virus (DENV). In contrast to the robust global transcriptome changes induced by DENV, ZIKV has a more selective and larger impact on expression of genes involved in DNA replication and repair. While overall expression profiles are similar, ZIKVC, but not ZIKVM, induces upregulation of viral response genes and TP53. P53 inhibitors can block the apoptosis induced by both ZIKVC and ZIKVM in hNPCs, with higher potency against ZIKVC-induced apoptosis. Our analyses reveal virus- and strain-specific molecular signatures associated with ZIKV infection. These datasets will help to investigate ZIKV-host interactions and identify neurovirulence determinants of ZIKV.

In response to the current global health emergency posed by the Zika virus (ZIKV) outbreak and its link to microcephaly and other neurological conditions, we performed a drug repurposing screen of ∼6,000 compounds that included approved drugs, clinical trial drug candidates and pharmacologically active compounds; we identified compounds that either inhibit ZIKV infection or suppress infection-induced caspase-3 activity in different neural cells. A pan-caspase inhibitor, emricasan, inhibited ZIKV-induced increases in caspase-3 activity and protected human cortical neural progenitors in both monolayer and three-dimensional organoid cultures. Ten structurally unrelated inhibitors of cyclin-dependent kinases inhibited ZIKV replication. Niclosamide, a category B anthelmintic drug approved by the US Food and Drug Administration, also inhibited ZIKV replication. Finally, combination treatments using one compound from each category (neuroprotective and antiviral) further increased protection of human neural progenitors and astrocytes from ZIKV-induced cell death. Our results demonstrate the efficacy of this screening strategy and identify lead compounds for anti-ZIKV drug development.

The Chi-chi earthquake (magnitude 7.6) on September 21, 1999 triggered numerous landslides in central Taiwan. A particularly large, deep-seated landslide occurred at Hungtsaiping, 15 km north of the epicenter. Field investigation and landscape evolution analysis revealed an irregular pattern of displacement vectors, indicating that this failure mechanism is highly complex. This paper presents the results of site investigations in conjunction with simulations of landscape evolution associated with this landslide. Analysis of landscape evolution was based on topographic maps produced at seven different times as well as aerial photographs taken between 1966 and 2006. Landslide site investigation included field reconnaissance, geomorphologic analysis, geophysical exploration, borehole logs, and laboratory experiments. Comprehensive geologic investigation led us to conclude that the materials involved in the landslide are colluvial deposits. Landscape evolution involved at least three large landslide events, two previous rockslides (the first triggered during the 1916 Nantou earthquake and another event occurring in 1934) as well as the 1999 colluvium slide (triggered during the Chi-chi earthquake). By taking into account the source of the collapsed mass, we were able to reproduce the three landslide events using a 3D discrete element model. Calibration of the parameters used in the numerical model was based on the strength characteristics of the rock mass as well as the morphology of the landslide deposits.

We prepared the fluorescent nanobelts of cyano-substituted 1,4-distyrylbenzene derivative (CNDSB) with the reprecipitation method. CNDSB is nonemissive in solution but with strong aggregation-induced emission (AIE) in belt-like structure. The molecular structure predicted by quantum chemical calculations indicates a twisted conformation of CNDSB monomer, while the solid-state X-ray structure of the CNDSB crystal features herringbone-type arrangement and three benzene rings arrange in nearly planar conformation. Femto- and picosecond time-resolved fluorescence spectroscopy are implemented to study the photophysics and the origin of the AIE effect in CNDSB nanobelts. The fluorescence quenching of CNDSB in THF solution arises from the efficient nonradiative isomerization channel. In this study, the fluorescence decay of CNDSB embedded in poly(methyl methacrylate) matrix is slowed down due to the restriction of intramolecular motions in the solid matrix. In nanobelt structure, the fluorescence lifetime furthe...

We designed heteroleptic ruthenium complexes (RD12-RD15) containing fluoro-substituted benzimidazole ligands for dye-sensitized solar cells (DSSCs). These dyes were synthesized according to a typical one-pot procedure with the corresponding ancillary ligands produced in two simple steps; they were prepared into DSSC devices according to the same conditions of fabrication. The eventual devices show a systematic trend of increasing VOC and decreasing JSC with fluorine atoms of increasing number substituted on the ligand. The charge-extraction results show that upward shifts of the TiO2 potential occurred when the fluoro-substituted dyes were sensitized on TiO2 with a systematic trend of shift N719 > RD15 (with 5 F) > RD12 (with 2 F) >RD5 (no F); the intensity-modulated photovoltage spectra indicate that those fluoro substituents retard charge recombination with the electron lifetimes (τR) in the order RD15 > RD12 > RD5 > N719, consistent with the variation of VOC for the systems.

We report three novel heteroleptic ruthenium complexes, RD1: Ru[(dcbpy)(1-methyl-2-(pyridin-2-yl)-1H-benzimidazole)(NCS) 2 , RD2: Ru [(dcbpy) (2-(pyridine-2-yl) benzothiazole) (NCS) 2 , and RD3: Ru[(dcbpy)(2-(pyridin-2-yl) benzoxazole) (NCS) 2 , for dye-sensitized solar cell applications. We found that RD 1 exhibits a dye loading amount two times higher than that of N719, which gives a broad IPCE action spectrum for the spectral response beyond 800 nm. This series of dyes can be easily synthesized in three steps with the best dye (RD 1 ) reaching 80 % cell performance of N719.

In 2009, Typhoon Morakot caused over 680 deaths and more than 20,000 landslides in Taiwan. From 2010 to 2015, the Central Geological Survey of the Ministry of Economic Affairs identified 1047 potential large-scale landslides in Taiwan, of which 103 may have affected human settlements. This paper presents an analytical procedure that can be applied to assess the possible impact of a landslide collapse on nearby settlements. In this paper, existing technologies, including interpretation of remote sensing images, hydrogeological investigation, and numerical analysis, are integrated to evaluate potential failure scenarios and the landslide scale of a specific case: the Xinzhuang landslide. GeoStudio and RAMMS analysis modes and hazard classification produced the following results: (1) evaluation of the failure mechanisms and the influence zones of large-scale landslides; (2) assessment of the migration and accumulation of the landslide mass after failure; and (3) a landslide hazard and evacuation map. The results of the case study show that this analytical procedure can quantitatively estimate potential threats to human settlements. Furthermore, it can be applied to other villages and used as a reference in disaster prevention and evacuation planning.

Based on the data of performance of all teams in two coalitions of National Football League (NFL) — American Football Coalition (AFC) and National Football Coalition (NFC), in 2005, we do the grey relational analysis to rank the fighting ability of 16 teams in each coalition. Then we do the cluster analysis and the discriminant analysis to investigate which teams with similar fighting ability or with potentiality of entering the playoff. Finally we do the data envelopment analysis (DEA) and the grey relational analysis to evaluate the managerial efficiency of all teams. In fight evaluation using the grey relational analysis result, 5 among the 6 teams with the highest fight ability in AFC and all 6 teams with the highest fight ability in NFC really entered the playoff. In the cluster analysis result, we distribute teams into the playoff group and the non-playoff group, and then only 2 teams in AFC and 1 team in NFC were in the wrong group. In the discriminant analysis result, there are only 1 tea...

We proposed “Additional Refresh Technology(ART)”, which has the features of low color washout and fast response speed by only modifying the pixel layout. Besides, by utilizing ART technology, the image can be real time optimized with simple method. ART have successfully been implemented as the Advanced-MVA(AMVA) mode for AUO's LCD-TV products, that ART has become the promising solution of advanced LCD-TV panels for mass-production.

Typhoon Megi (2010) had brought intense rainfall and hit the northeastern part of Taiwan. It caused a widespread rock fall, debris slide, rock slide, and debris flows along highway Route 9. The multi-hazard susceptibility map based on logistic regression approach and rock mass rating system (RMR) was adopted to evaluate the landslide susceptibility in this study. Firstly, the multi-hazard susceptibility model categorized the hazard potential for different geological hazards into low, moderate, and high level. Secondly, the study performed a geomechanical classification system for rocks according to field investigation along the vulnerable road section. The result reveals that a semi-quantitative hazard matrix combining with the both evaluations can assess the geological hazard appropriately. In addition, the high-resolution DEM extracted from airborne LiDAR and multi-temporal remote sensing images had been analyzed to examine the morphological change and geological structure for the landslide location with a high susceptibility. Finally, the detailed landslide susceptibility with three levels on highway is proposed and verified.

Catastrophic landslides and debris slides triggered by intense storms such as Typhoon Morakot (2009) occurred more frequently in recent years, and caused many casualties and economic loss in Taiwan. For the purpose of reducing damage resulted from geological hazards, this study collected landslide inventory which contains the information of occurrence such as time, location, size of failure, mean rainfall intensity, and rainfall duration with new measurement techniques. The precipitation data, satellite image, geology, terrain unit, topography mapping, and field survey are then combined to GIS for extracting the triggering factors of landslide. Furthermore, the multi period event-based landslide inventory and corresponding data are performed to establish the shallow landslide prediction model by logistic regression method and critical rainfall threshold for landslide early-warning system also developed. The landslide susceptibility model, landslide hazard scenario technique, and early-warning system were developed based on the systematical event-based landslide inventory. Validation with more than 200 cases show that the accuracy of the model is about 75–85% and the result could be applied to regional land-use planning, construction site selection, disaster prevention, and mitigation for civil infrastructure.

A simple catalyst system for the selective oxidative C—C double bond cleavage of gem-disubstituted alkenes (I) is reported.

Summary Zika virus (ZIKV) directly infects neural progenitors and impairs their proliferation. How ZIKV interacts with the host molecular machinery to impact neurogenesis in vivo is not well understood. Here, by systematically introducing individual proteins encoded by ZIKV into the embryonic mouse cortex, we show that expression of ZIKV-NS2A, but not Dengue virus (DENV)-NS2A, leads to reduced proliferation and premature differentiation of radial glial cells and aberrant positioning of newborn neurons. Mechanistically, in vitro mapping of protein-interactomes and biochemical analysis suggest interactions between ZIKA-NS2A and multiple adherens junction complex (AJ) components. Functionally, ZIKV-NS2A, but not DENV-NS2A, destabilizes the AJ complex, resulting in impaired AJ formation and aberrant radial glial fiber scaffolding in the embryonic mouse cortex. Similarly, ZIKA-NS2A, but not DENV-NS2A, reduces radial glial cell proliferation and causes AJ deficits in human forebrain organoids. Together, our results reveal pathogenic mechanisms underlying ZIKV infection in the developing mammalian brain.