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Splicing, a key step in the eukaryotic gene-expression pathway, converts precursor messenger RNA (pre-mRNA) into mRNA by excising introns and ligating exons. This task is accomplished by the spliceosome, a macromolecular machine that must undergo sequential conformational changes to establish its active site. Each of these major changes requires a dedicated DExD/H-box ATPase, but how these enzymes are activated remain obscure. Here we show that Prp28, a yeast DEAD-box ATPase, transiently interacts with the conserved 5′ splice-site (5′SS) GU dinucleotide and makes splicing-dependent contacts with the U1 snRNP protein U1C, and U4/U6.U5 tri-snRNP proteins, Prp8, Brr2, and Snu114. We further show that Prp28’s ATPase activity is potentiated by the phosphorylated Npl3, but not the unphosphorylated Npl3, thus suggesting a strategy for regulating DExD/H-box ATPases. We propose that Npl3 is a functional counterpart of the metazoan-specific Prp28 N-terminal region, which can be phosphorylated and serves as an anchor to human spliceosome., Yeast helicase Prp28 promotes the first step of spliceosome remodeling. By placing a photoactivatable unnatural amino acid in Prp28, the authors capture Prp28 in action revealing its dynamic interactions and cofactor Npl3.

The 2018 Mw 6.4 Hualien earthquake generated a large peak-to-peak velocity of over 2 m/s, with a period of 3 s at the south end of the Milun fault, which resulted in the collapse of five buildings. To investigate the shallow subsurface soil structure and evaluate possible effects on the ground motion and building damage, we performed microtremor measurements in the Hualien basin. Based on the velocity structure jointly inverted from both Rayleigh-wave dispersion curves and microtremor horizontal-to-vertical spectral ratio data, we found that the shallow subsurface structure generally deepens from west to east. Close to the Milun fault, the structure becomes shallower, which is consistent with faulting during the 2018 earthquake and the long-term tectonic displacement. There is no significant variation for the site conditions in the north–south direction that can explain the large peak ground velocity in the south. As a result of the dense measurements in the heavily damaged area, where three high-rise buildings totally collapsed, these locations have the average S-wave velocity of the upper 30 m (AVS30) values and are relatively high compared to the more distant area from the Meilun River. This is somewhat unusual, because lower AVS30 values indicating softer ground conditions are expected close to the river. We did not find any characteristic subsurface soil structure that may contribute to the building collapses. The large 3 s pulse was probably generated by source effects, rather than subsurface soil amplification.

We propose a methodology to implement horizontal-to-vertical Fourier spectral ratios (HVRs) evaluated from strong ground motion induced by earthquake (EHVRs) or ambient ground motion observed from microtremor (MHVRs) individually and simultaneously with the spatial correlation (SC) in a ground-motion prediction equation (GMPE) to improve the prediction accuracy of site effects. We illustrated the methodology by developing an EHVRs-SC-based model which supplements Vs30 and Z1.0 with the SC and EHVRs collected at strong motion stations, and a MHVRs-SC-based model that supplements Vs30 and Z1.0 with the SC and MHVRs observed from microtremors at sites which were collocated with strong motion stations. The standard deviation of the station-specific residuals can be reduced by up to 90% when the proposed models are used to predict site effects. In the proposed models, the spatial distribution of the predicted station terms for peak ground acceleration (PGA) from MHVRs at 3699 sites is consistent with that of the predicted station terms for PGA from EHVRs at 721 strong motion stations. Prediction accuracy for stations with inferred Vs30 is similar to that of stations with measured Vs30 with the proposed models. This study provides a methodology to simultaneously implement SC and EHVRs, or SC and MHVRs in a GMPE to improve the prediction accuracy of site effects for a target site with available EHVRs or MHVRs information.

Electrospun nanofiber membranes possess high specific surface area with small pores and thus can be developed as wound dressings for absorbing exudate and also preventing bacterial penetration. In this study, hydroxypropyl cellulose (H), chitosan (C) and polyethylene oxide (P) were chosen as membrane materials to increase the hydrophilicity, anti-bacterial property, and yield of nanofibers, respectively. Additionally, graphene (G) was added to enhance the anti-bacterial property of the membranes. As indicated by SEM, the HCP and HCPG solutions (containing H:4.5 wt%, C:4.5 wt%, P:0.75 wt%, without/with G:0.5 wt%) could be electrospun into HCP and HCPG nanofiber membranes with good fiber morphology using a non-toxic solvent system. Further, the membranes were crosslinked by glutaraldehyde vapor to improve the strength. The tensile strength of the membranes was 1.38–1.82 MPa with a swelling ratio up to 1330–1410%. The water vapor transmission rate (WVTR) of wet HCPG membrane was about 3100 g/m2-day, close to the recommended WVTR of wound dressings. The anti-bacterial properties of the membranes were confirmed using three tests against Escherichia coli (Gram-negative bacterium) and Staphylococcus aureus (Gram-positive bacterium). Highly hydrophilic HCP and HCPG membranes prevented the bacterial adherence. The presence of the membranes (especially graphene-embedded HCPG membrane) also greatly reduced bacterial growth. The small pore sizes of HCP and HCPG nanofiber membranes prevented the bacterial penetration to cause infection. Taken together, the HCP and HCPG nanofiber membranes possessed good mechanical properties, appropriate WVTR and high water absorption thus suitable for absorbing wound exudate. Besides, the membranes exhibited nontoxic, anti-fibroblast adhesion and anti-bacterial properties. Therefore, HCP and HCPG nanofiber membranes have the potential to become superior anti-bacterial wound dressings.

Background/Purpose: To examine ethnic disparity in prevalence and associated factors of myopia in adolescents using the Unites States National Health and Nutrition Examination Survey (NHANES) dataset. Methods: Participants who were aged 12–19 years were included from NHANES (1999–2008). Logistic regression analyses were applied to identify risk factors associated with myopia after stratification by race. Results: A total of 9,960 participants were included in the prevalence analysis, and 6,571 in the risk factor analysis. Other race (excluded Mexican American, other Hispanic, non-Hispanic white, non-Hispanic black) participants had the highest frequency of myopia (42.77%). Multivariate analyses of the whole population suggested that the odds of myopia were significantly lower in participants with household smokers (odds ratio [OR] = 0.79, 95% confidence interval [CI]: 0.66–0.97), and significantly greater in Mexican American race (OR = 1.28, 95% CI: 1.01–1.62), other Hispanic (OR = 1.79, 95% CI: 1.10–2.92) and in participants with senior high school graduate education (OR = 1.79, 95% CI: 1.01–3.18), watched 2 hours of television daily (OR = 1.27, 95% CI: 1.02–1.59), used the computer for 1 hour daily (OR = 1.276, 95% CI: 1.02–1.57). When examined by race/ethnicity, 1 hour of computer use increased the odds of myopia in the non-Hispanic White group, in Mexican Americans a higher family poverty income ratio and 2 hours of television time was associated with myopia, and in the Other Hispanic group, a higher family poverty income ratio was associated with myopia, while males and those with a higher sugar had a lower risk of myopia. Conclusion: Risk factors for myopia vary with race/ethnicity. Keywords: Adolescent, Myopia, Racial disparity, Risk factor, NHANES

Peak ground acceleration (PGA) can be used to estimate the seismic intensity. However, using P-wave features to estimate PGA is a challenging task. One of the reasons for that is that a seismic wave commonly undergoes modification due to various site effects, consequently leading to uncertainty in the predicted PGA. In order to accommodate site effects using site parameters together with P-wave parameters, this paper takes advantage of machine learning to consider multiple parameters simultaneously. Several artificial neural network (ANN) models considering different site effect parameters are constructed. The performances of these ANN models were investigated and compared. In total, 53531 ground motion data obtained from the Taiwan Strong Motion Instrumentation Program were utilized to develop the proposed approach. It was found that the proposed ANN model with horizontal-to-vertical spectral ratio parameters effectively reduces the error of the estimated PGA when compared with either the ANN model without site parameters or the ANN model with other site parameters.

The high-frequency decay parameter kappa (κ) was computed by fitting Fourier amplitude spectra from the seismic network of the Taiwan Strong Motion Instrumentation Program (TSMIP). The κ of shear horizontal waves (SH waves) was calculated for individual recordings, and the relationship between κ values and the epicentral distance (Repi) of each station was derived for each station. The κ value at Repi = 0 (denoted as κ0) can be used as a site parameter. There are totally 26,277 seismograms that have been recorded at 679 TSMIP stations over the period of 1993 through 2014 with local magnitudes of 4.0–7.1 and focal depths less than 30 km. The estimation of κ0 for Taiwan ranges from 0.0208 to 0.147 s, and the spatial distribution of κ0 was closely related to geology and velocity. The site-specific κ0 values from 425 stations were correlated with the averaged shear wave velocity of the top 30 m of strata (VS30), and the relationship could be described as κ0 = (0.125 ± 0.005) − (0.011 ± 0.001) × ln(VS30), and an acceptable linear correlation (R2 = 0.57) was performed. The results may be used in the future application of ground motion prediction equations (GPMEs) and serve as simulation parameters. Also, the relationship between κ0 and the depth to engineering rock (Z1.0) is not well correlated, whereas an acceptable correlation exists between κ0 and other site proxies (i.e., elevation and resonant frequency).

Recently, energy conservation has been concerned, and there are several aspects to improve the energy consumption issues. Therefore, many research results were proposed to mitigate the related problems, one of these is to eliminate the extra standby power of household appliances. This paper employed an effective method to identify load characteristics of appliances in different operation states by support vector machines, and a smart home electric energy saving system was built up to implement the method. Furthermore, a virtual living room was simulated in the laboratory as an experimental object, and a prototype system was built up. The performance test results are proposed to validate the feasibility of the proposed system.

The strong ground motion of 6 February 2018 M 6.2 Hualien Earthquake triggered a series of co-seismic geomagnetic fluctuations and seismo-traveling atmospheric disturbances (STADs) signatures in infrasonic waves and micro-pressures upon the seismic wave arrival. Networks of 9 QuakeFinder systems, 3 infrasound systems, 2 tiltmeters, 2 micro-barometers, and 11 co-located seismometers are used in this study. Each QuakeFinder system consists of a 3-axes induction magnetometer, an air conductivity sensor, a geophone, and temperature/relative humidity sensors. Co-seismic signatures clearly appear in the induction magnetometers, infrasound systems, and micro-barometers data. The magnetometers register both high- and lowfrequency pulsations. Geomagnetic fluctuations occur upon the seismic wave arrival but last a longer duration, while the STADs lag their co-located seismic waves by about 15 - 45 s. The long-lasting fluctuations recorded by both induction and fluxgate magnetometers suggest that the ground/underground water motion play an important role, which is further conformed by low-frequency fluctuations in the tiltmeter data. In general, the amplitude of geomagnetic fluctuations decays as away from the epicenter. However, unusual large co-seismic geomagnetic fluctuations are detected over areas of the abnormal seismic intensity level and/or the magnetic underground structure with anomalously high susceptibilities.

Nanofibrous biomaterials fabricated by electrospinning attract increasing attention. However, electrospun nanofibers are stacked tightly, thus restricting cell infiltration and nutrient supply. To overcome this drawback, we developed three types of cytocompatible nanofiber membranes, namely (1) electrospun chitosan/gelatin/PEO (CGP) composite membrane, (2) co-electrospun CGP/E membrane containing CGP and Eudragit (E) nanofibers, (3) CGP (E removed) membrane which was obtained by selective removal of E nanofibers from CGP/E membrane. The permeability of albumin through CGP, CGP/E, and CGP (E removed) nanofiber membranes increased from 1.50 × 10−11 to 6.19 × 10−11 and further to 15.3 × 10−11 m2/s, respectively. Hence, incorporating large-diameter (space-forming) E nanofibers with CGP nanofibers enhanced the permeability of CGP/E membrane. Moreover, selectively removing E nanofibers from CGP/E membrane further enlarged pore size and created more permeable CGP (E removed) membrane. Membrane strength and stability were reinforced by crosslinking with glutaraldehyde for 2.5 h. To verify our approach, stem cells (KP-hMSCs) were covered by CGP (E removed) or CGP membrane and cultured for 7 days. The cell density underneath CGP (E removed) membrane was about 1.7 times of that underneath CGP membrane, indicating that improved cell growth (proliferation) occurred under CGP (E removed) membrane. Therefore, our approach to create more permeable nanofiber membranes for better cell growth is successful and can be utilized for fabricating various nanofibrous biomaterials.

Broadband seismometers, ground-based Global Navigation Satellite Systems (GNSS), and magnetometers that were located within an epicentral distance of approximately 150 km consistently observed the novel anomalous behaviors of the common-mode ground vibrations approximately 5–10 days before the M6.6 Meinong earthquake in Taiwan. The common-mode ground vibrations with amplitudes near 0.1 m at frequencies ranging from 8 × 10−5 to 2 × 10−4 Hz were generated near the region close to the epicenter of the impending earthquake. The common-mode vibrations were consistently observed in seismic and GNSS data associated with five other earthquakes in four distinct areas. The results reveal that the common-mode vibrations could be a typical behavior before earthquakes. The causal mechanism of common-mode vibrations can be attributed to crustal resonance excitations before fault dislocations occur. Potential relationships with other pre-earthquake anomalies suggest that the common-mode vibrations could be ground motion before earthquakes, which was investigated for a significant length of time.

There are two kinds of bedrocks that are widely used in seismology and earthquake engineering respectively. The seismology field uses the “seismic bedrock” to define an interface that has a practically lateral extent. The strata deeper than this interface is much more homogeneous in comparison with the shallower one. It is common to set the seismic bedrock within the upper crust has 3000 m/sec of the shear wave velocity. In contrast, the earthquake engineering prefers the shallower interface which dominates the main seismic site amplification, especially the predominant frequency of ground motion. The interface is called “Engineering Bedrock”, which the underlying stratum has the shear wave velocity from 300 to 1000 m/sec for different purposes. But, the reference shear wave velocity of the engineering bedrock is mostly defined as 760 m/sec for ground motion prediction and simulation. In Taiwan, the Central Weather Bureau (CWB) constructed and operates a dense strong-motion network called TSMIP (Taiwan Strong Motion Instrument Program), which provides numerous ground motion data for seismology and earthquake engineering. In our previous studies, the shallow shear wave velocity profiles of over 700 TSMIP stations were estimated by the Receiver Function method. The velocity profiles are from the ground surface to the depth with the shear wave velocity of at least 2000 m/sec. It allows us to compare the theoretical site amplification of the velocity profile of TSMIP stations with their observed one from the seismic records. The variance of fitness between theoretical and observed amplifications through shear wave velocity is analyzed to evaluate which reference velocity can appropriately define the depth of engineering bedrock, where the most site amplification occur beneath, in all of Taiwan. The difference between local geology is also discussed. Finally, an engineering bedrock map is proposed for further applications in earthquake engineering.

Site amplification behavior are important in ground motion prediction. Seismic waves were amplified and caused significant building damages in the Taipei Basin by the 1986 Hualien offshore (subduction interface) and the 1999 Chi-Chi earthquakes (crustal), for which both of the epicentral distances were nearly 100 km. To understand local site amplifications in Taiwan, empirical site amplification factors for both horizontal and vertical ground motions are studied using recently constructed strong motion and site databases for the free-field TSMIP stations. Records of large magnitude earthquakes of MW larger than 5.5 from 1991 to 2016 were selected for this study. Site amplification factors at site conditions with Vs30 between 120 m/s to 1600 m/s and bedrock accelerations up to 0.8 g were evaluated using ratios of spectral accelerations at different periods. The reference site condition, i.e. the engineering bedrock, is assumed as Vs30 of 760 m/s (B/C boundary) in this study. Our empirical site amplification form are borrowed from the site response function of ASK14 and CY14 ground motion models in NGA-West2 project with slight modification. Therefore our site amplification model includes a linear amplification term and a nonlinear deamplification term. The coefficients of the empirical models were obtained by a nonlinear regression analysis using the selected Taiwan data. Site amplification factor is a function of Vs30 and spectral intensity in the model. Similar linear site amplification factor to the NGA models is derived in our model; however, more significant soil nonlinearity behavior than the NGA models is likely captured from the empirical data. The amplification factor in vertical component is smaller than that in horizontal.

This study analyzed site effects including PGA and empirical transfer functions at 15 selected surface–downhole stations by using ground motion recordings of earthquakes with ML > 4 during 2012 and 2013 in Taiwan. In addition, we used all strong motion recordings of four large earthquakes (ML > 6) to generate intensity distribution maps and assess the differences in magnitude at the surface and downhole. The site amplification factors of the PGA were calculated using the ratio between the surface and downhole recordings. The mean PGA amplification factors ranged from 2 to an exaggerated value of 20 at different stations. In addition, the power law relationships between the PGAs at the surface and downhole were evaluated to understand how amplification varies as PGA increases. Strong ground motions with and without site effects throughout Taiwan could be observed by comparing intensity distribution maps generated using the surface and downhole accelerations from four large earthquakes with magnitudes > 6. Empirical transfer functions derived using the single-station and two-station methods at the same stations showed comparable dominant frequencies and amplification factors; however, the empirical transfer function derived using the two-station method showed clearer resonance peaks, not only at fundamental frequencies but also at higher mode resonance frequencies. The HHSR and the HVSR were highly similar, particularly at medium frequencies. This finding indicates that the HVSR can be used instead of the HHSR when only the surface recording is available. Moreover, the local magnitudes calculated using surface recordings were higher than those calculated using downhole recordings. The differences are attributed to the amplification caused by the sedimentary layers and resultant in 0.36, 0.46 and 0.49 on average for events with ML of > 6, 5–6, and 4–5. Furthermore, HHSRs at 5–10 Hz and 1.1–1.7 Hz were strongly correlated with PGA amplifications and ML differences, respectively.

Novel physical properties not seen in their individual layers are obtained from stacked layers of materials. In this report, using the first-principles calculations, we study the electronic band structures of heterostructures composed of graphitic (graphene-like) bilayers of g-ZnO/ZnX (X = S, Se, and Te) semiconductors. The g-ZnO layer is largely planar, but the ZnX layer is somewhat corrugated. Our calculations reveal on the stable formations of a type-II band alignment in bilayers with an AB stacking order of OZnO-ZnZnX and ZnZnO-XZnX. The optical bandgaps are much lowered as compared to the monolayers of ZnO and ZnX constituents, with the conduction band contributed by g-ZnO and valence band by ZnX. There is a quadratic dependence of the bandgap on the external electric biases applied in perpendicular to the interface. This nonlinearity manifests an superposed effect of an interlayer orbital hybridization and associated charge transferring, along with the coexistence of an electric dipole and a quadrupole. There is an overall charge transfer of valence electrons from the ZnX layer to the g-ZnO layer, leading to a pair of highly charge polarized surfaces along with a large built-in potential. The already lowered bandgaps further change with the external bias. This tunability of Eg for g-ZnO/ZnX bilayer heterostructures holds promises for optoelectronic applications covering a wider spectral range of the solar spectrum.

This study aimed to characterize the changes in the visual field (VF) patterns and disc morphology of patients with thyroid-associated orbitopathy (TAO) and open-angle glaucoma (OAG). A retrospective review of the medical records at the Tri-Service General Hospital in Taiwan identified 396 eyes of 198 patients with thyroid-associated glaucoma. A final follow-up of VF examination in 140 eyes revealed 114 eyes with VF defects, indicating disease progression. The characteristics of and changes in disc morphology, optical coherence tomography findings, and VF defects were statistically analyzed. The most common VF defects at the initial diagnosis and the end of the follow-up period were inferior partial arcuate (17%) and paracentral (15%) defects, respectively. The most common VF defect in patients with unspecific disc signs was an unspecific scotoma (13%). The most common optic disc feature was disc cupping (51%), followed by parapapillary atrophy (48%). The most frequent location of nerve fiber layer thinning was the inferotemporal region (48%). VF defects showed a significantly more pronounced progression in the non-nerve fiber bundle group than in the nerve fiber bundle group (p &lt, 0.001). This study details the characteristics and progression of disc morphology and VF defects in patients with TAO and OAG.

The damping ratio is an important index used in soil nonlinearity studies and is mostly proportional to the shear strain increase. Previous researches indicated a frequency-independent damping in most cases. In this study, frequency-dependent damping was introduced from frequency-dependent Q calculated through the spectral ratio method of near-surface structures using the power spectrum of strong motion records in the Strong Motion Array in Taiwan Phase I (SMART1). The dense SMART1 recorded significant strong motions in the 1980s, which can be used to identify soil nonlinearity at near surfaces. A 40%–50% increase in frequency-dependent damping for SMART1 was identified, with strain increasing from 0.01% to 0.1% in near-surface regions. A large damping was also found in the shallow sediments with mean Vs below 600 m/s on the topmost 500 m layers in the SMART1 database at a frequency range of 3–8 Hz, which is independent of the magnitude scaling or near-field travel distance scaling relations.

On February 12, 2014, an ML 4.2 earthquake (named 0212 EQ) occurred at the Tatun Volcano Group (TVG) in northern Taiwan. Seismic data from both the regional broadband array in Taiwan and a local dense seismic network in the TVG indicate that the 0212 EQ was located at a depth of 4.3 km near Shamoshan, one of the latest eruptive units in the TVG. Referring to the aftershocks surrounding the 0212 EQ, we further found that (1) they formed a linear seismic zone dipping ∼50° towards the southeast to reach the Shanchiao Fault that cuts through the TVG, (2) focal mechanism of more than half of the larger aftershocks (MD ≥ 1.5) matched this linear seismic zone for a normal faulting, and (3) the seismic b-value was calculated to be 3.55. They are used to delineate the geometry of the Shanchiao Fault at the upper crust and to infer that localized geothermal fluid might have affected the activity of aftershocks as manifested by the very high seismic b-value. The strongly compensated linear vector dipole of the centroid moment tensor suggests the 0212 EQ had a non-double-couple source resulted from the gravitational collapse. Thus, we conclude that the 0212 EQ was a combined synergistic effect of a collapsed reservoir filled with volcanic fluids and faulting activities along the Shanchiao Fault.

Long-period pulse-like strong ground motions were recorded near the Milun fault and caused serious building damages in the Hualien City during the main shock of the 2018 Hualien, Taiwan, earthquake. In this paper, questionnaire survey on feeling of shaking, indoor damages, structural, and nonstructural damages to high-rise reinforced concrete residential buildings were analyzed by three building groups according to the positions to the Milun fault and different site conditions. Relationships between the results of questionnaire survey on building damages and characteristics of strong ground motions were studied. Furthermore, a characterized seismic source model was proposed to elucidate the generation mechanism of near-fault long-period strong ground motions. In this model, a shallow strong motion generation area (SMGA7) in the south part of Milun fault with rise-time of 2.6 s contributed to the long-period pulse-like strong ground motions. Besides, a deep SMGA (SMGA8) under the SMGA7 with rise-time of 1.2 s also contributed to the strong ground motions. Using this model, strong ground motions at the sites of buildings for questionnaire survey were synthesized. Because of the directivity effects, amplitudes of ground motions were increased from north to south along the Milun fault, which can explain the serious building damages at the buildings located at the southwest to the Milun fault. The reasons of building damages were also examined from the aspect of predominant periods of ground sites and fundamental periods of buildings, which were extracted from microtremor measurement. Damages at the buildings located on the central part of the hanging wall with relatively good site condition were the lightest for almost all the surveyed items. Pulses with period in the range of 1 s–2 s which were generated by the SMGA8 and amplified by the near surface layers are considered to be responsible for building damages.