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Phalaenopsis, an essential flower for export, is significantly affected by fusarium wilt, which impacts its export quality. Hyperspectral imaging technology offers the potential to detect fusarium wilt on Phalaenopsis. The goal of this study was to establish an automated platform for the rapid detection of fusarium wilt on Phalaenopsis. In this research, the automatic target generation process (ATGP) method was employed to identify outliers in the hyperspectral spectrum. Subsequently, the Spectral Angle Mapper (SAM) method was utilized to detect signals similar to the outliers. To suppress background noise and extract the region of interest (ROI), the Constrained Energy Minimization (CEM) method was implemented. For ROI classification and detection, a deep neural network (DNN), a support vector machine (SVM), and a Random Forest Classifier (RFC) were employed. Model performance was evaluated using three-dimensional receiver operating characteristics (3D ROC), and the automated identification system was integrated into hyperspectrometers. The proposed system achieved an accuracy of 95.77% with a total detection time of 3380 ms ± 86.36 ms, proving to be a practical and effective tool for detecting fusarium wilt on Phalaenopsis in the industry. [ABSTRACT FROM AUTHOR]

This paper studies a composite device composed of ferroelectric random access memory (FeRAM) and metal-oxide-semiconductor field effect transistor. The relationship between the hysteresis characteristics and VG is reported, and the on/off ratios under different writing voltages are presented. The gm–VG curve of the forward and reverse sweeping shows that under forward sweep a very clear instability appears while voltage increases. The reasons for this can be explained according to the voltage divider rule, the ID formula, and gm formula of transistors, which show that there is polarization of the ferroelectric material. Accordingly, a method is proposed to determine the critical point of the ferroelectric capacitor polarization in this 1T1C structure, which is advantageous because it identifies the appropriate reading voltage necessary for an effective program state of the 1T1C device. This method was shown in three 1T1C and three FeRAMs devices with different ferroelectric areas. Finally, this method was verified by the P–V loop of FeRAMs. [ABSTRACT FROM AUTHOR]

Dispensing micron-scale droplets from a suspended nozzle is important for applications in bioprinting, analytical chemistry, and pharmaceutical formulation. Here, we describe a general approach to eject droplets from microfluidic devices using superhydrophobic patterning; this facilitates release of wetted fluids, allowing droplets to break contact with channel surfaces and travel along regular paths to achieve a printing accuracy of ∼3 μm. We demonstrate the utility of the approach by using it to print droplets of varied composition from a microfluidic mixing device. Our approach is compatible with common fabrication techniques making it applicable to devices configured for diverse applications. [ABSTRACT FROM AUTHOR]

Understanding the circumstances and conditions surrounding disaster‐attributed deaths may contribute to designing and implementing emergency preparedness and response programmes. This paper introduces a three‐step cluster analysis of multiple binary variables to investigate mortality patterns related to tropical cyclones. It is designed to overcome the difficulties of performing cluster analysis in a disaster database that is composed in part of nominal variables and is unavoidably incomplete owing to missing information. The first step in the process codes all variables as binary data in order to accommodate the nominal variables. The second step calculates Spearman's rank correlation coefficients for pairs of variables. And the third step subjects the correlation coefficients to cluster analysis. Data related to 1,575 deaths attributed to tropical cyclones (also known as typhoons) that struck Taiwan between 2000 and 2015 are used to illustrate the method. The results yield two distinct groups of variables that are worthy of further exploration. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) is a popular additive manufacturing (AM) technique for the fabrication of precise components. The success of SLM relies on accurate control of the melt pool, where the metal powder melts and solidifies. Fluid flow inside the melt pool is driven by forces like Marangoni force and recoil pressure. SLM process begins with the fabrication of support, which involves the process of joining dissimilar metals. A strong support-base substrate connection ensures the success of subsequent additive manufacturing. In this study a comprehensive model was developed to predict the dimensions and characteristics of the melt pool with a focus on the first layer of the SLM process. An initial numerical simulation was done to obtain transient melt pool temperature and velocity distribution during the SLM process. The results were then coupled with a theoretical analysis development of the proposed model. The effectiveness of the model was validated by experimental results and melt pool characteristics from previous publications. The model shows Root Mean Square Error (RMSE) of 0.53 and 0.49 for height-to-width ratio and normalized area, respectively. The Mean Absolute Percentage Error (MAPE) of normalized area is 15.7 % for the majority of the data, which demonstrates a good accuracy of the model. In addition, the transition from conduction mode to keyhole mode can be identified with the model. This model can be used to rapidly and effectively predict the melt pool characteristics for SLM and other similar AM processes with a wide range of processing parameters. [ABSTRACT FROM AUTHOR]

Abstract This article presents a study on the influence of selective laser melting (SLM) process on microstructure and property of a cemented carbide system containing high entropy alloy. Analysis along the building direction indicated variation of chemical composition and microstructure, and this was influenced by two effects, firstly the dilution effect due to elemental diffusion from the baseplate and secondly the elements evaporation caused by high-power laser. At the lower half of the specimen, high fraction of η-carbide formed near the level of baseplate, and there were chemical gradients of major binder elements along the building direction. At the upper half of the specimen, there were relatively less variation in chemical composition and more homogeneously distributed phases including WC, W 2 C, η-carbide and FCC metal binder. The hardness of the lower half specimen varied from 711.7 HV1 (bottom of the specimen) to 1178.6 HV1 at 1 mm height. For the upper half of the specimen, hardness values could range from 1306.8 HV1 to 1413.4 HV1 and fracture toughness varied from 9.74 MPa m1/2 to 13.29 MPa m1/2. Highlights • A complex cemented carbide system was subjected to selective laser melting process. • The cemented carbide system contains a high entropy alloy. • Composition and microstructure of the cemented carbide were heterogeneous. • Dilution effect, evaporation, and laser scanning tracks could affect the built. • Hardness and toughness varied due to variation in composition and microstructure. [ABSTRACT FROM AUTHOR]

Motivation Programmed ribosomal frameshifting (PRF) is widely used by viruses and bacteria to produce different proteins from a single mRNA template. How steric hindrance of a PRF-stimulatory mRNA structure transiently modifies the conformational dynamics of the ribosome, and thereby allows tRNA slippage, remains elusive. Results Here, we leverage linear response theories and resolution-exchanged simulations to construct a structural/dynamics model that connects and rationalizes existing structural, single-molecule and mutagenesis data by resolution-exchanged structural modelling and simulations. Our combined theoretical techniques provide a temporal and spatial description of PRF with unprecedented mechanistic details. We discover that ribosomal unfolding of the PRF-stimulating pseudoknot exerts resistant forces on the mRNA entrance of the ribosome, and thereby drives 30S subunit rolling. Such motion distorts tRNAs, leads to tRNA slippage, and in turn serves as a delicate control of cis-element's unwinding forces over PRF. Availability and implementation All the simulation scripts and computational implementations of our methods/analyses (including linear response theory) are included in the bioStructureM suite, provided through GitHub at https://github.com/Yuan-Yu/bioStructureM. Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

This article presents detailed microstructure characterization of cemented carbide fabricated by selective laser melting process. Nickel-coated tungsten carbide powders were used for this study; the selective laser melting process induced complex microstructure consisting of partially-melted carbide, carbide precipitates and dendritic microstructure. Four phases were identified, i.e. MC, M 2 C, FCC and η in the as-built specimen. CALPHAD phase diagram was utilized to describe possible phase formation sequence during selective laser melting process, which involved melting, solidification and repeated heating. Although the composition of initial powder was very simple (spherical W 2 C-WC and Ni-coating), selective laser melting allowed the decomposition of initial carbides, subsequent formation of dendritic structure and precipitation of additional carbides. To the best of authors' knowledge, for the first time, detailed microstructure characterization of cemented carbide fabricated by selective laser melting is presented. [ABSTRACT FROM AUTHOR]

The bioequivalence of two Florfenicol (FF) products in pigs was evaluated. A 2 × 2 crossover trial with a 14 days wash-out period was performed. The pigs were orally administered in a single dose (2 mg/kg b.w of FF). Serum samples were analyzed using a liquid chromatography-tandem mass spectrometry method. The limit of quantification was 0.1 ng/mL, and the calibration range was 1.0-100.0 ng/mL. Furthermore, intraday and interday were 5.43-9.09% and 6.23-9.68%, respectively. The areas under the curve (AUC0-48) for the test product B of FF and reference product A were 7289.61 ± 1750.44 and 6545.01 ± 2766.25 h × ng/mL, respectively. The highest concentrations of FF in the serum (Cmax) were 726.05 ± 211.77 and 641.97 ± 117.94 ng/mL. The mean retention times (MRT) was 7.91 ± 1.98 and 7.76 ± 2.89 h while the half-lives (T1/2) were 4.07 ± 1.71 and 4.99 ± 3.30 h. From the analysis of variance results, the p values of Cmax and AUC0-∞ for the 90% confidence interval were 0.492 and 0.320 (p > 0.05), respectively. A comparison between the test product and the reference product showed no significant difference. Both products showed bioequivalence after being administered in pigs. [ABSTRACT FROM AUTHOR]

In recent years, a rapid bridge health monitoring technology has been developed using an instrumental moving vehicle. Using recorded vehicle vibration data, bridge frequencies are identified for bridge health monitoring or finite element model updating. Target bridge frequencies with significant amplitudes in the vehicle’s vibration frequency spectra are expected to be found. However, in the coupled vehicle–bridge interaction (VBI) system, bridge vibration-relevant vehicle dynamics might not be noticeable. The bridge frequency would be difficult to identify because of the potential influence of road roughness. To resolve this difficulty, a novel bridge frequency identification method is proposed to mitigate the negative effects of road roughness. First, theoretical derivations are done to ascertain the VBI system dynamic characteristics considering road surface roughness. Our findings showed that the road roughness-relevant vehicle dynamics are closely related with the traveling speed, whereas the bridge frequency remains approximately constant. Theoretical investigations indicated that cross-power spectra between vehicle dynamics at multiple moving speeds are effective to mitigate the negative effects of road roughness. Presumably, it is feasible to identify the target bridge frequency from the cross-power spectra. Both the dynamic characteristics of the VBI system and the effectiveness of the proposed method for bridge frequency identification were examined using finite element simulations and laboratory experiments. Compared to existing methods, the proposed method is widely applicable to real-world situations and difficulties. [ABSTRACT FROM AUTHOR]

Bridge damage detection has become increasingly important, but few related techniques have been tested in situ on real bridges. For this study, a field experiment was conducted on an actual simply supported steel truss bridge with four artificial damage scenarios applied sequentially. Preliminary results of modal-parameter identification and vibration-based damage detection are then presented. For each scenario, modal frequencies and mode shapes of the bridge were identified with high precision and accuracy using a stabilization diagram-aided multivariate autoregressive analysis of vehicle-excited bridge vibrations. Changes in the identified modal parameters attributable to the artificial damage were observed. For modal frequencies, they decreased as damage causing high stress redistribution was applied, signifying a global stiffness loss. For mode shapes, both symmetric and anti-symmetric ones were distorted when the damage was applied asymmetrically, but no distortion was observed when damage was applied symmetrically. Moreover, a damage detection approach in an order of feature extraction and discrimination was verified to be practicable if the damage-sensitive feature was properly selected. Multiple modal frequencies, specifically the first three and four modal frequencies, were effective features because they were highly sensitive not only to the presence but also to the severity of the artificial damage. Multiple modal assurance criteria (MAC) values and coordinate modal assurance criteria (COMAC) values were also effective features that were sensitive to damage scenarios examined herein if sufficient modes were considered. However, neither a single frequency nor a single MAC value was as effective as multiple ones because each was sensitive to certain specific damage scenarios only. When damping ratios were taken as features, most of their combinations were slightly sensitive to the asymmetric damage, but none of those combinations, neither single nor multiple damping ratios, was sensitive to the symmetric damage. [ABSTRACT FROM AUTHOR]

The selective laser melting (SLM) process involves irradiation from a high-power laser to melt and sinter powdered material. The high temperature gradient near the laser spot generates high residual stress that can lead to failure of fabricated parts. Estimation of the residual stress for real transient SLM processes by simulation involves considerable computation effort which makes its application in real industrial SLM processes rather difficult. To tackle this challenge, a two-stage coupled transient thermomechanical model with a quasi-transient heat source was developed. In the first stage, a transient thermal analysis was performed to acquire temperature distribution of the full SLM process. The temperature distribution serves as thermal loading input for subsequent transient thermal stress analysis. This quasi-transient thermomechanical model can provide residual stress data consistent with that of a conventional full transient model in 68% less computation time. The data provided by the new model also includes the dynamic stress release due to re-heating and re-melting in overlapped laser scanned regions which was in close confirmation with experimental results. This efficient quasi-transient model is useful for rapid analysis and optimization of SLM processing parameters. [ABSTRACT FROM AUTHOR]

A novel method for online extraction, pH-gradient separation, and analysis of nine non-steroidal anti-inflammatory drugs (NSAIDs) was developed by coupling online eluent-switching technique to single anion-exchange chromatographic column/ion trap mass spectrometer (MS) and used for monitoring NSAIDs residues in pig serum. A neutral eluent and a pH-gradient eluent were used for extraction and separation of NSAIDs, respectively. Each of nine NSAIDs has an MS precursor ion of either [M−H] − or [M−Na] − . The extracted ion chromatogram for a specific product ion of each NSAID was used for its quantitative analysis. The dynamic linear ranges of calibration curves were all 0–200 ng mL −1 ( R 2 > 0.9950). The analysis accuracies estimated by spiking standard concentrations at 20, 100, and 200 ng mL −1 were 80.5–99.9%. The corresponding intra-day and inter-day precisions (RSD%) were 2.5–14.5% and 2.9–15.2%, respectively. The limit of detection/limit of quantitation of NSAIDs were 1.3/4.3, 0.5/1.6, 0.2/0.5, 2.5/8.2, 1.5/4.9, 0.6/2.1, 0.6/2.0, 0.5/1.7, and 0.6/2.1 ng mL −1 for carprofen, diclofenac, flunixin, ibuprofen, ketoprofen, meclofenamic acid sodium, mefenamic acid, niflumic acid, and tolfenamic acid, respectively. After 1 h injection of a dose containing 2 mg kg −1 weight pig of flunixin and tolfenamic acid to the pigs, a residue amount of 3480 ± 36 ng mL −1 and 431 ± 13 ng mL −1 , respectively, was reached for the incurred pig serum specimens and both residues were reduced to about 20 ng mL −1 at the time of 24 h. [ABSTRACT FROM AUTHOR]

Although the dynamic motions and peptidyl transferase activity seem to be embedded in the rRNAs, the ribosome contains more than 50 ribosomal proteins (r-proteins), whose functions remain largely elusive. Also, the precise forms of some of these r-proteins, as being part of the ribosome, are not structurally solved due to their high flexibility, which hinders the efforts in their functional elucidation. Owing to recent advances in cryo-electron microscopy, single-molecule techniques, and theoretical modeling, much has been learned about the dynamics of these r-proteins. Surprisingly, allosteric regulations have been found in between spatially separated components as distant as those in the opposite sides of the ribosome. Here, we focus on the functional roles and intricate regulations of the mobile L1 and L12 stalks and L9 and S1 proteins. Conformational flexibility also enables versatile functions for r-proteins beyond translation. The arrangement of r-proteins may be under evolutionary pressure that fine-tunes mass distributions for optimal structural dynamics and catalytic activity of the ribosome. [ABSTRACT FROM AUTHOR]

Background/Purpose: Mineral Trioxide Aggregate (MTA) was widely used as a root-end filling material and for vital pulp therapy. A significant disadvantage to MTA is the prolonged setting time has limited the application in endodontic treatments. This study examined the physicochemical properties and biological performance of novel partially stabilized cements (PSCs) prepared to address some of the drawbacks of MTA, without causing any change in biological properties. PSC has a great potential as the vital pulp therapy material in dentistry. Methods: This study examined three experimental groups consisting of samples that were fabricated using sol-gel processes in C3S/C3A molar ratios of 9/1, 7/3, and 5/5 (denoted as PSC-91, PSC-73, and PSC-55, respectively). The comparison group consisted of MTA samples. The setting times, pH variation, compressive strength, morphology, and phase composition of hydration products and ex vivo bioactivity were evaluated. Moreover, biocompatibility was assessed by using lactate dehydrogenase to determine the cytotoxicity and a cell proliferation (WST-1) assay kit to determine cell viability. Mineralization was evaluated using Alizarin Red S staining. Results: Crystalline phases, which were determined using X-ray diffraction analysis, confirmed that the C3A contents of the material powder differed. The initial setting times of PSC-73 and PSC-55 ranged between 15 and 25 min; these values are significantly (p<0.05, ANOVA and post-hoc test) lower than those obtained for MTA (165 min) and PSC-91 (80.5 min). All of the PSCs exhibited ex vivo bioactivity when immersed in simulated body fluid. The biocompatibility results for all of the tested cements were as favorable as those of the negative control, except for PSC-55, which exhibited mild cytotoxicity. Conclusion: PSC-91 is a favorable material for vital pulp therapy because it exhibits optimal compressive strength, a short setting time, and high biocompatibility and bioactivity. [ABSTRACT FROM AUTHOR]

This paper investigated the feasibility of the pseudo-static damage identification method derived from a bridge–vehicle interaction system through a moving vehicle laboratory experiment. The element stiffness index, defined as the ratio of flexural rigidity of a damaged member to that of an intact member, serves as the damage indicator. Three vehicle models and two travelling speeds were considered in the experiment to examine the effect of vehicle's dynamic characteristic and travelling speed on identified results. It is demonstrated that locations and severities of damages are detectable using the proposed method in spite of the probable changes of roadway roughness and environmental conditions. In addition, adopting higher vehicle speed as well as the vehicle with frequency close to that of the bridge increased the probability of detecting damages. [ABSTRACT FROM AUTHOR]

Highlights: [•] An online sample pretreatment technique coupled LC/MS/MS was developed. [•] A matrix-matched internal standard calibration method was used for maduramicin residue determination in chicken meat. [•] An ion enhancement effect was found for maduramicin detection. [•] Maduramicin residues in incurred chickens decrease during the withdrawal period. [ABSTRACT FROM AUTHOR]

• Agglomeration of CoAl 2 O 4 inoculants follows the scan direction. • Modifying the scan speeds and energy densities can inhibit the agglomeration. • CoAl 2 O 4 was reduced within the melt pool to from Co-rich particles. • The extent of melt pool remelts the Co-rich particles present in deposited layers. • Insufficient energy input may lead to a slight fraction of unreacted CoAl 2 O 4. [Display omitted] The investigation aims to clarify the influence of scan parameters on the morphology and phase constitution of CoAl 2 O 4 inoculants in Inconel 718 (IN718) superalloy processed by selective laser melting (SLM). Gas atomized IN718 powder feedstock was uniformly blended with 0.2 wt% of CoAl 2 O 4 flakes and processed with a range of laser scan parameters to understand the effect of the inoculant additions on microstructure. Similar to the reactions observed in investment cast Ni-superalloys, the CoAl 2 O 4 particles were found to chemically react with elemental Al, Cr, and Ti present in the melt pool of IN718 and become reduced into Al 2 O 3 , Cr 2 O 3 , and TiO 2 oxides after the SLM process. Analyses of single melt pool beads revealed the existence of Co-rich metallic particles distributed along the surface of the oxides. However, since SLM processing involves remelting of the previously deposited layers to minimize the occurrence of porosity, this results in the dissolution of the Co-rich metallic particles that form when the CoAl 2 O 4 particles are reduced in the melt pool. As such, the ability of the metallic Co particles to contribute to grain refinement becomes limited during SLM processing. Furthermore, the inoculant particles were found to agglomerate along the scan direction. The underlying mechanisms can be attributed to the Marangoni convection following the moving center of laser beam. It was found that decreasing energy density and increasing scan speed can effectively reduce the size and number density of the agglomerated oxide particles. Faster laser scan velocities lead to reduced convective flow within the melt pool and reduce the tendency for agglomeration. However, the reduced magnitude of energy input limited the time over which the CoAl 2 O 4 particles could react with the melt pool. This led to the formation of lack of fusion defects and incomplete chemical reaction between CoAl 2 O 4 and IN718 after the SLM process. The effectiveness of CoAl 2 O 4 inoculant particles on grain refinement in as-built SLM IN718 microstructures is strongly dependent on the melt pool physics and laser scan conditions. [ABSTRACT FROM AUTHOR]

Programmed ribosomal frameshifting (PRF) serves as an intrinsic translational regulation mechanism employed by some viruses to control the ratio between structural and enzymatic proteins. Most viral mRNAs which use PRF adapt an H-type pseudoknot to stimulate -1 PRF. The relationship between the thermodynamic stability and the frameshifting efficiency of pseudoknots has not been fully understood. Recently, single-molecule force spectroscopy has revealed that the frequency of -1 PRF correlates with the unwinding forces required for disrupting pseudoknots, and that some of the unwinding work dissipates irreversibly due to the torsional restraint of pseudoknots. Complementary to single-molecule techniques, computationalmodeling provides insights into global motions of the ribosome, whose structural transitions during frameshifting have not yet been elucidated in atomic detail. Taken together, recent advances in biophysical tools may help to develop antiviral therapies that target the ubiquitous -1 PRF mechanism among viruses. [ABSTRACT FROM AUTHOR]

Our objective in this study was to promote the growth of bone cells on biomedical titanium (Ti) implant surfaces via surface modification involving sandblasting, alkaline etching, and type I collagen immobilization using the natural cross-linker genipin. The resulting surface was characterized in terms topography, roughness, wettability, and functional groups, respectively using field emission scanning electron microscopy, 3D profilometry, and attenuated total reflection-Fourier transform infrared spectroscopy. We then evaluated the adhesion, proliferation, initial differentiation, and mineralization of human bone marrow mesenchymal stem cells (hMSCs). Results show that sandblasting treatment greatly enhanced surface roughness to promote cell adhesion and proliferation and that the immobilization of type I collagen using genipin enhanced initial cell differentiation as well as mineralization in the extracellular matrix of hMSCs. Interestingly, the nano/submicro-scale pore network and/or hydrophilic features on sandblasted rough Ti surfaces were insufficient to promote cell growth. However, the combination of all proposed surface treatments produced ideal surface characteristics suited to Ti implant applications. [ABSTRACT FROM AUTHOR]

The selective laser melting (SLM) process is an additive manufacturing technique that can fabricate three-dimensional workpiece by laser scanning and sintering of designated material in powder form on a preset scanning route along a bed of powders. This process involves a moving laser heating source which causes local transient mass and heat transfer with phase change, i.e., melting and solidifying, in a pool of melted powders. To fully investigate such a complicated transport process with reasonable computation cost, a novel quasi-transient numerical model (hopping model) was proposed and validated experimentally in this study. This approach includes a volumetric heat source defined as an elliptical Gaussian laser spot which hops along the scan path. Inconel 718 (IN718) superalloy powder is selected as the material for demonstration. Thermal analysis was carried out using a number of laser power and scan speeds in the range from 80 W to 120 W and from 80 mm/s to 140 mm/s, respectively. The comparison of molding appearance of the work pieces from the developed hopping model, full transient model, effective-transient model, and experiments illustrates the accuracy and the efficiency of the proposed hopping model. Molding appearance obtained from the quasi-transient model was consistent with experimental results with a relative error of less than 1.71% on the width of the IN718 stripes fabricated by SLM. For the cases analyzed in the current study, the quasi-transient model showed a 99% and a 60% reduction in both the computation time and the amount of computer memory needed compared to the full transient model and the effective-transient model, respectively. This novel quasi-transient simulation technique can be used to rapidly and effectively optimize process parameters for intelligent additive manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes (CNT) were grown in anodic aluminum oxide (AAO) and used as field emitters in a triode structure. To fabricate the field-emission triode structure, nanoporous anodic aluminum oxide (AAO) thin layer was first prepared on the Si(100) substrate, followed by the growth of vertically aligned carbon nanotubes in AAO pore channels by electron cyclotron resonance chemical vapor deposition (ECR-CVD). The SiO2 dielectric and Al gate electrode layers required for the triode structure were directly deposited on the CNTs. Reactive ion and wet etches were then used to open the field-emission area in the triode. Scanning electron microscopy and Raman spectroscopy studies revealed that damage to CNT emitters in the etched area was trivial. Field-emission characteristics of the CNT emitters have been studied and an anode turn-on electric field of ∼8.05 V/μm was measured. [Copyright &y& Elsevier]

In this study, electrical measurements on ferroelectric random-access memory by prior x-ray irradiation are conducted. Compared with an unirradiated device, parameters such as current leakage and remnant polarization of the irradiated device were unexpectedly improved. Besides, better reliabilities including the number of endurance times and retention time have also been demonstrated. To clarify the underlying physical mechanism, the electrical properties are analyzed. The current–voltage curve (I–V) implies a change in the grain size in the ferroelectric layer (FL), and the capacitance–voltage curve (C – V) profile indicates that the FL undergoes a phase change during irradiation. Finally, according to the electrical results, a physical model is proposed as an explanation. [ABSTRACT FROM AUTHOR]

This paper presents a unified framework for dynamic analysis of vehicle-bridge interaction (VBI) systems using a commercial finite element software suite (ABAQUS ®). This framework can provide bridge designers and engineering practitioners with a general platform to analyze the coupled system with high modeling efficiency and accuracy in modeling and outputting. Moreover, it has readily available nonlinear material/element models and nonlinear dynamic analysis functions for complex structures. This analysis framework was first validated with a classical VBI problem involving a sprung mass moving on a simply supported beam, whose closed-form solution is readily available. Validation for the application on complex structure was then presented with a typical 16-car Japanese high-speed train (Shinkansen) and a three-block bridge. The cars comprised car bodies, bogies and wheelsets, which were all modeled as rigid bodies and which were connected with springs and dashpots. The bridge was modeled with typical three-dimensional solid elements. Interaction between wheelsets and tracks was realized using the penalty method. Rail irregularity was also considered in the analysis. The consistency between calculated dynamic responses and field experiment data of certain pre-specified observation points validated the proposed method. Furthermore, ease in analyzing VBI problems involving nonlinear material properties and with high spatial resolutions was demonstrated with a classical cracked beam problem: a point mass moving on a simply supported cracked beam. Both linear and nonlinear crack models were employed. The former model assigned crack surfaces with a mechanical contact property and showed its accuracy in comparison to the reference model. The latter assigned a nonlinear material model in crack-prone zones and illustrated the potential applicability to dynamic crack propagation simulation in VBI problems. The present framework was further applied to seismic response analysis of a train-bridge interaction system involving material nonlinearity and separation between track and wheel under a strong earthquake. [ABSTRACT FROM AUTHOR]

To investigate the driving safety of vehicles travelling on bridges which cross the sea in cold regions, this study presented a dynamic analysis framework for a vehicle–bridge–soil interactive system subjected to stochastic ice loads. Time histories of the stochastic ice loading based on real ice loading spectrum were obtained to consider them as external forces inputs to the vehicle–bridge–soil interaction model. Dynamic responses of a five-span continuous box-girder bridge seated on pile-type foundations under twelve 12-DOF truck vehicles moving are investigated. These numerical analyses revealed that both the bridge and vehicle vertical responses were little affected by lateral ice loads, although their lateral responses were dominated by ice loads. For vehicle driving safety, the front axle tires were more prone to sideslip accidents than rear axle tires were: higher vehicle speed, larger ice loading magnitude, and more slippery pavement adversely affected driving safety. Quantitative analysis was also done using the present dynamic analysis framework. In the worst case studied herein, the front axle tires approached sideslip status, with only 5 kN sideslip force resistance. [ABSTRACT FROM AUTHOR]

Highlights • A nonlinear bridge seismic analysis method incorporating moving vehicles is proposed. • This method integrates ABAQUS into an in-house vehicle-bridge interaction program. • Vehicles raised displacement response of the bridge but reduced acceleration response of the bridge. • The relative displacements of bearings were reduced regarding moving vehicles. • Natural frequency variation of the bridge may affect its seismic responses. Abstract Seismic design codes for highway bridges and viaducts in most countries do not specify the simultaneous presence of live vehicle loads and earthquake loads. However, urban highway bridges and viaducts are loaded constantly by heavy traffic, therefore it is important to elucidate the effects of moving vehicles on the seismic response of bridges. This paper proposed a seismic response analysis framework incorporating vehicle–bridge interactions (VBI) with nonlinear dynamic analysis. The proposed method integrates a commercial FEA package, ABAQUS, into the authors' in-house VBI-solving programs developed using MATLAB. With the proposed method, the effects of vehicle dynamics on seismic responses of a highway bridge could be clarified and the seismic performance of the bridge could be checked. For the bridge and ground motions studied herein, it was observed that continuously moving vehicles might yield larger longitudinal displacement responses at pier tops and plastic deformations at pier bottoms than those of the bridge alone, implying that ignoring vehicles' additional mass effect and dynamic effects during earthquakes might be on the non-conservative side. Acceleration responses of pier tops and relative displacements of bearings were generally reduced by the moving vehicles. Besides the reason that the vehicles act like dampers on the bridge, it was most probably that the vehicle-bridge in-phase modes were excited by specific ground motions to a level lower than the original bridge-alone mode was, which could be indicated from their corresponding pseudo acceleration response spectra. Although the out-of-phase modes were excited to a similar level to the original bridge-alone mode was, these modes might dissipate some seismic energy that would have been dissipated by the bridge components and reduced displacement of the bearing. [ABSTRACT FROM AUTHOR]

As a transmitter power amplifier (PA), the electrical output characteristics of gallium nitride (GaN) high electron mobility transistors (HEMTs) are closely related to the drain current versus drain voltage (${I}_{d}$ – ${V}_{d}$) characteristics. Any abnormalities in the ${I}_{d}$ – ${V}_{d}$ characteristics will seriously affect device performance. Therefore, many groups have investigated the kink effect of GaN HEMTs. One of the commonly used measurement methods of the kink effect is the ${I}_{d}$ – ${V}_{d}$ forward and reverse sweep. In this study, we used the same method for Al2O3/Si3N4–AlGaN/GaN metal–insulator–semiconductor HEMT (MIS HEMT) devices. We found that not only did the kink effect occurred but ${I}_{d}$ also increased abnormally during the reverse sweep and after a series of electrical measurements. At the end of the forward sweep, impact ionization caused by a high ${V}_{d}$ generated electron–hole pairs and some holes accumulated under the gate region, which caused the negative shift of the threshold voltage (${V}_{\text{Th}}$), leading to an abnormal increase in ${I}_{d}$ during the reverse sweep. [ABSTRACT FROM AUTHOR]

For maintenance of infrastructures, advanced inspection techniques applicable to diagnosis and prognosis are increasingly in great demands. Elastic-wave computed tomography (CT) is one of the techniques that have been extensively applied to the inspection of concrete structures. This conventional technique requires inputs being recorded and hence limits the number of inputs and relevant examined ray paths in acknowledging that the number of sensor is limited and sensor installation is time-consuming in the field. To tackle this difficulty, we presented a hybrid CT method by introducing the concept of acoustic emission (AE) localization to the conventional elastic wave CT, enabling simultaneous identification of both elastic-wave velocity distributions and input locations. With this hybrid method, the velocity distribution can be constructed with no input information required, implying a saving in number of sensor and in sensor installing time. It also implies that inputs can be performed arbitrary times at arbitrary locations for yielding sufficient examined path rays even with a limited number of receiving sensors. In this study, we applied this technique to the single-side tomography of surface waves excited by mechanical impacts. The feasibility of this hybrid CT method was illustrated on a 1.5 × 1.5 × 0.3 m concrete specimen and on a cracked concrete wall in field. Also, its superior efficiency and resolution was shown. [ABSTRACT FROM AUTHOR]

This study investigates the recovery behavior of GaN high-electron mobility transistors on SiC substrates under different hot-carrier stress conditions. The threshold voltage shifts positively due to hot electron trapping at the buffer layer under hot-carrier stress. However, the recovery between semi-on (Vt < VG < 0 V) hot-carrier stress and on-state (VG > 0 V) carrier stress is significantly different. This phenomenon is systematically discussed in terms of the applied gate voltage under stress condition, which affects the occupation of the surface donor states. After applying a semi-on hot-carrier stress, the threshold voltage continues to shift positively after relaxing the applied voltage. In contrast, the threshold voltage exponentially recovers after applying an on-state hot-carrier stress. Silvaco technology computer aided design (TCAD) simulation was performed to verify the effect of the surface donor state on the threshold voltages. Since switching between on-state and off-state in RF-applications includes both conditions, we suggest that the surface donor states are crucial to determine the failure of devices. [ABSTRACT FROM AUTHOR]

Epidermal growth factor receptor (EGFR) is often constitutively stimulated in many cancers owing to the binding of ligands such as epidermal growth factor (EGF). Therefore, it is necessary to investigate the interaction between EGFR and its targeting biomolecules. The main aim of this study was to estimate the binding affinity and adhesion force of two targeting molecules, anti-EGFR monoclonal antibody (mAb LA1) and the peptide GE11 (YHWYGYTPQNVI), with respect to EGFR and to compare these values with those obtained for the ligand, EGF. Surface plasmon resonance (SPR) was used to determine the equilibrium dissociation constant (KD) for evaluating the binding affinity. Atomic force microscopy (AFM) was performed to estimate the adhesion force. In the case of EGFR, the KD of EGF, GE11, and mAb LA1 were 1.77 × 10−7, 4.59 × 10−4 and 2.07 × 10−9, respectively, indicating that the binding affinity of mAb LA1 to EGFR was higher than that of EGF, while the binding affinity of GE11 to EGFR was the lowest among the three molecules. The adhesion force between EGFR and mAb LA1 was 210.99 pN, which is higher than that observed for EGF (209.41 pN), while the adhesion force between GE11 and EGFR was the lowest (59.51 pN). These results suggest that mAb LA1 binds to EGFR with higher binding affinity than EGF and GE11. Moreover, the adhesion force between mAb LA1 and EGFR was greater than that observed for EGF and GE11. The SPR and AFM experiments confirmed the interaction between the receptor and targeting molecules. The results of this study might aid the screening of ligands for receptor targeting and drug delivery. [ABSTRACT FROM AUTHOR]

Abstract: Cyanophycin is a natural source of polypetide consisting of aspartic acid as a backbone and arginine as its side chain. After the removal of arginine, the remaining poly-aspartate can be served in numerous industrial and biomedical applications. The synthesis of cyanophycin is catalyzed by cyanophycin synthetase. In this study, we used lactic acid bacteria to produce cyanophycin by nisin-controlled gene expression system (NICE). The cyanophycin synthetase gene cphA of Synechocystis sp. strain PCC6803 was cloned to the vector pNZ8149 followed by transformation into Lactococcus lactis subsp. cremoris NZ3900. The effects of nisin concentrations and the amounts of supplemented aspartic acid and arginine were examined for the production of cyanophycin. Alterations of the terminus of cphA gene were also conducted in an attempt to increase the yield of cyanophycin. An optimal cyanophycin production was noted under a culture condition of log phase induced at 250ng/mL nisin in M17L medium supplemented with 20mM arginine and 10mM aspartic acid. An insertion of glycine residue at the C terminus of cyanophycin synthetase resulted in a yield of 20% of dry cell weight, a 10-fold increase when compared with the wild type. The results showed that recombinant lactic acid bacteria, a GRAS system, could provide an alternative approach of producing cyanophycin suitable for agricultural and biomedical applications. [Copyright &y& Elsevier]

This study compares the capacitance–voltage (C–V) characteristics in silicon–germanium (SiGe) metal-oxide-semiconductor capacitances with and without a silicon oxide capping layer. The SiGe channel with the silicon oxide capping layer exhibits an improved C–V property at room temperature but has an abnormal shift and depression at low temperature (77 K). We determined that the threshold voltage shift was induced by the Fermi-level when ambient temperature was changed. The additional silicon capping layer was responsible for introducing defects resulting in depression and hump in the C–V measurements. Such a phenomenon is mainly caused by the different distribution of defects, which was established by modifying the alternating current pulse amplitude during the C–V measurement. [ABSTRACT FROM AUTHOR]

2D semiconductor field‐effect transistors (2D FETs) have emerged as a promising candidate for beyond‐silicon electronics applications. However, its device performance has often been limited by the metal‐2D semiconductor contact, and the non‐negligible contact resistance (RSD) not only deteriorates the on‐state current but also hinders the direct characterization of the intrinsic properties of 2D semiconductors (e.g., intrinsic charge carrier mobility, μint). Therefore, a proper extraction technique that can independently characterize the metal‐2D semiconductor contact behavior and the intrinsic properties of a 2D semiconducting layer is highly desired. In this study, a universal yet simple method is developed to accurately extract the critical parameters in 2D FETs, including characteristic temperature (To), threshold voltage (VT), RSD, and μint. The practicability of this method is extensively explored by characterizing the temperature‐dependent carrier transport behavior and the strain‐induced band structure modification in 2D semiconductors. Technology computer aided design simulation is subsequently employed to verify the precision of RSD extraction. Furthermore, the universality of the proposed method is validated by successfully implementing the extraction to various 2D semiconductors, including black phosphorus, indium selenide, molybdenum disulfide, rhenium disulfide, and tungsten disulfide with top‐ and bottom‐gated configurations. [ABSTRACT FROM AUTHOR]

The HfZrOx (HZO) ferroelectric material is a promising material for ferroelectric memory and is compatible with the semiconductor process for ferroelectric random access memory (FeRAM) and negative capacitance field effect transistor. However, defects often exist in the grain boundary to influence the performance or reliability of devices. In addition, uniformity between devices must be considered when they are mass-produced. Therefore, the grain size will become important in determining the performance and reliability. In this study, we use electrical measurements of current–voltage, capacitance–voltage, and polarization–voltage measurements to test high- and low-temperature deposition devices, with a transmission electron microscope (TEM) image to confirm the grain size. Finally, we propose a model to explain the phenomenon and provide a method to obtain better ferroelectric memory. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanofibers (CNFs) were grown in the porous anodic aluminum oxide (AAO) thin film grown on the Si wafer by electron cyclotron resonance chemical vapor deposition using cobalt as the catalyst. A larger Co particle electrodeposited in the AAO pore channel produced vertically aligned CNFs with a tube diameter in compliance with the pore size of the AAO template. On the other hand, a smaller Co particle resulted in CNF growth with a nonuniform distribution of the tube diameter and a sparse tube density. Amorphous carbon residue produced under the plasma-assisted CNF growth condition seemed to play an essential role leading to the observation. A growth mechanism is proposed to delineate the volume effect of the electrodeposited Co catalyst on the CNF growth confined in pore channels of the AAO template. [Copyright &y& Elsevier]

Abstract: Dental restorative composite resins with effective fluoride release and recharge properties have yet to be developed. In this study, we developed three types of polymer–kaolinite nanocomposite resins (C(K-diamine), C(K-acrylamide), and C(K-acetate)) with the potential to provide sustained release of fluoride due to the strong adsorption of kaolinite to fluoride during the fabrication process. Their mechanical (hardness, flexural strength, flexural modulus, fracture toughness, and diametral tensile strength) and fluoride release properties were investigated. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses demonstrated that hexanediamine, acrylamide, and ammonium acetate were successfully intercalated into the interlamellar structure of all three resins. Of the three types of polymer–kaolinite nanocomposite resins, C(K-acrylamide) exhibited the greatest mechanical strength and greater fluoride release than Fuji IX. In addition, C(K-acrylamide) released more fluoride than Fuji IX and Z-100 after exposure to 0.2% NaF. It is concluded that C(K-acrylamide) can potentially serve as a useful restorative material with caries-preventive properties. [Copyright &y& Elsevier]

Droplet libraries consisting of many reagents encapsulated in separate droplets are necessary for applications of microfluidics, including combinatorial chemical synthesis, DNA-encoded libraries, and massively multiplexed PCR. However, existing approaches for generating them are laborious and impractical. Here, we describe an automated approach using a commercial array spotter. The approach can controllably emulsify hundreds of different reagents in a fraction of the time of manual operation of a microfluidic device, and without any user intervention. We demonstrate that the droplets produced by the spotter are similarly uniform to those produced by microfluidics and automate the generation of a ~ 2 mL emulsion containing 192 different reagents in ~ 4 h. The ease with which it can generate high diversity droplet libraries should make combinatorial applications more feasible in droplet microfluidics. Moreover, the instrument serves as an automated droplet generator, allowing execution of droplet reactions without microfluidic expertise. [ABSTRACT FROM AUTHOR]

This work investigates a low-temperature and high-pressure (LTHP) hydrogen treatment in Si-channel and SiGe-channel metal–oxide–semiconductor capacitors (MOSCAPs). The LTHP hydrogen treatment can repair dangling bonds in the SiO2/Si and SiO2/SiGe interfaces to enhance device performance. Additional parameters of the treatment, including treatment pressure and time, are also investigated to better understand the reaction mechanisms, which further proves the effectiveness and potential of this supercritical fluid (SCF)-based treatment. In addition, this treatment will not damage the front structure and materials due to the relatively low process temperature (120 °C). Therefore, this treatment can be a nondestructive postannealing process. The results of extracting interface defect density (Dit) by the conductance method show that there is an ~51% reduction in the defect density after this posttreatment, a significant decrease. Finally, a TCAD simulation of different defect densities verifies the repair mechanism of deep-level defects. [ABSTRACT FROM AUTHOR]

This work investigates the effect of process temperature on one-transistor-one-capacitor ferroelectric random access memory (1T1C FeRAM) cells fabricated with a HfZrOx ultrathin film applied as the 1T1C capacitor. Traditionally, the capacitor in 1T1C devices is grown on the drain, and such a structure is a type of dynamic memory. Such a structure, however, is prone to the leakage current phenomenon, which causes the amount of charge stored in the capacitor to be insufficient, leading to inaccurate data reading. To solve this problem, an alternative 1T1C structure placing the capacitor on the gate terminal has been proposed. For these alternative 1T1C FeRAM devices, our experimental results indicate that the deposition temperature of the ferroelectric layer has a significant effect on the basic electrical properties. To clarify this phenomenon, we propose a physical model which is based on the effect of the deposition temperature on the HfZrOx grain size. [ABSTRACT FROM AUTHOR]

The generation of defect states in p-MOSFETs under negative bias temperature instability (NBTI) has been extensively discussed in previous literature. However, only a few studies have discussed the relationship between interface defects and off-state leakage. Therefore, this article analyzes the impact of interface defects generated by NBTI on gate-induced drain leakage (GIDL). In general, GIDL is generated through band-to-band tunneling (BTBT) at large gate-to-drain bias (VGD). In this article, NBTI causes an increase in GIDL at extremely low VGD. By measuring at different temperatures and comparing the GIDL generated from hot carrier degradation (HCD), it was confirmed that the GIDL would still be generated through trap-assisted tunneling (TAT) and thermal excitation at an extremely low VGD. [ABSTRACT FROM AUTHOR]

This work investigates the effects of HfO2 layer defects, formed by the Al atoms in the metal gate, on performance and reliability in advanced n-type metal–oxide–semiconductor field-effect transistors (n-MOSFETs) with different Al content in the gate stacks. Many groups have proposed theories (e.g., Si–H bond dissociation, trapped in high- ${k}$ defects and impact ionization) to explain the degradation mechanisms in MOSFETs, with most focusing on the dissociation of the Si-H bond at the Si/SiO2 interface and the carrier trapping in the high- $k$ layer. However, for multi- ${V}_{{\text {th}}}$ devices, experimental results indicate that the formation of defects by Al atoms in the HfO2 layer is the main reason for degradation in advanced n-MOSFETs. Therefore, we propose a mechanism to clarify the deterioration in advanced n-MOSFETs with different Al content in the gate stacks, and this mechanism is confirmed by positive bias temperature instability (PBTI), hot carrier instability (HCI), HCI power-law fitting and the gate-induced drain leakage (GIDL) measurement. [ABSTRACT FROM AUTHOR]

Fusion-based additive manufacturing (AM) has significantly grown to fabricate Nickel-based superalloys with design freedom across multiple length scales. Several phenomena such as feedstock/energy source/melt pool interactions, solidification and phase transformations occur during fusion-based AM processes of Nickel-based superalloys, which determine the ultimate microstructure and mechanical performance of the built parts. In this review, we elaborate a comprehensive discussion on AM Nickel-based superalloys and influential factors including feedstock characteristics (powder morphology, chemistry, contamination, flowability, recycling) and AM processing (parameters, and powder spreading/wall/balling/spattering effects) on their microstructure (micro-segregation, phases formations and grain structures), defect generation (sub-surface/internal defects, microcracks, surface roughness, and residual stress). Furthermore, the mechanical properties of AM Nickel-based superalloys such as tensile, creep and fatigue at room/elevated temperatures are analyzed in accordance with the initial, and post processing effects. Additionally, the commonly utilized modeling approaches in literature to predict the microstructure and mechanical behavior of these alloys are highlighted. Finally, the current challenges and mitigation approaches for future research are identified considering the gaps in the AM Nickel-based superalloys. [ABSTRACT FROM AUTHOR]

• Vibration-based model updating and damage detection of an actual steel truss bridge is conducted. • Possibility of damage detection of the actual steel truss bridge was observed by means of the vibration-based model updating. • Importance of damage modeling in FE model updating based on vibration measurements is revealed. • Importance of model classes in the FE model updating is revealed. • Importance of the physical meaning of model parameters in the model updating is revealed. As the finite element (FE) model has become increasingly important in engineering, the model updating method has also received much attention as a means of improving the structural FE model accuracy. However, the objectives of many earlier studies have been laboratory experiments and numerical simulations. Actual structures have not been adequately investigated. This report describes work on a vibration-based Bayesian model updating for an actual steel truss bridge. The transitional Markov chain Monte Carlo (TMCMC) sampling method was used to estimate the posterior distribution. A field experiment assessing this target bridge was conducted under five damage scenarios. Then a fast Bayesian FFT method was used to identify the modal properties. Based on sensitivity analysis, three model classes were proposed for the model updating process of the target bridge. In all cases, the updated modal properties were found to fit well with the experimental data, whereas the updated model parameters cannot. The case with more prior information identified the structural damage. Results demonstrate that making full use of prior information can improve the model updating accuracy. Feasibility of damage detection was observed for an actual steel truss bridge based on the FE model updating method. [ABSTRACT FROM AUTHOR]

Background: The combination of biliary stent with photodynamic and chemotherapy seemed to be a beneficial palliative treatment of unresectable cholangiocarcinoma. However, by intravenous delivery to the target tumor the distribution of the drug had its limitations and caused serious side effect on non-target organs. Therefore, in this study, we are going to develop a localized eluting stent, named PDT-chemo stent, covered with gemcitabine (GEM) and hematoporphyrin (HP).Methods: The prototype of PDT-chemo stent was made through electrospinning and electrospraying dual-processes with an electrical charge to cover the stent with a drug-storing membrane from polymer liquid. The design of prototype used PU as the material of the backing layer, and PCL/PEG blends in different molar ratio of 9:1 and of 1:4 were used in two drug-storing layers with GEM and HP loaded respectively.Results: The optical microscopy revealed that the backing layer was formed in fine fibers from electrospinning, while drug-storing layers, attributed to the droplets from electrospraying process. The covered membrane, the morphology of which was observed by scanning electron microscopy (SEM), covered the stent surface homogeneously without crack appearances. The GEM had almost 100% of electrosprayed efficiency than 70% HP loaded on the covered membrane due to the different solubility of drug in PEG/PCL blends. Drug release study confirmed the two-phased drug release pattern by regulating in different molar ratio of PEG/PCL blends polymer.Conclusions: The result proves that the PDT-chemo stent is composed of a first burst-releasing phase from HP and a later slow-releasing phase from GEM eluting. This two-phase of drug eluting stent may provide a new prospect of localized and controlled release treatment for cholangiocarcinoma disease. [ABSTRACT FROM AUTHOR]

Martensitic phase transformation is an important strengthening mechanism for 17-4 PH stainless steel; this study has investigated the martensite fractions of 17-4 PH stainless steel processed by selective laser melting (SLM) with systematic variation in energy densities through adjustments in laser power, scanning speed, and hatch distance. Interestingly, the fractions of martensite have shown a positive correlation with the energy densities for specific hatch distance. Finite element analysis has suggested that an increase in energy density could promote higher residual stress to induce higher fractions of martensite due to greater thermal contraction during SLM process. Furthermore, this study has shown that a decrease in the hatch distance could induce higher fractions of reverted austenite due to more laser scanning overlaps, leading to a decrease in martensite fractions. Prediction equations based on SLM parameters for martensite fractions in 17-4 PH stainless steel have been established; this work demonstrates that martensite fractions of 17-4 PH stainless steel in as-built state can be designed by SLM process. • 17-4 PH stainless steel has been investigated by different SLM parameters. • Martensite fractions can be controlled by both energy density and hatch distance. • Higher energy density can increase martensite fractions for a given hatch distance. • Finite element analysis successfully correlates with experiments. • An equation to predict martensite fractions has been established. [ABSTRACT FROM AUTHOR]

Life ticks as fast as how proteins move. Computationally expensive molecular dynamics simulation has been the only theoretical tool to gauge the time and sizes of these motions, though barely to their slowest ends. Here, we convert a computationally cheap elastic network model (ENM) into a molecular timer and sizer to gauge the slowest functional motions of structured biomolecules. Quasi-harmonic analysis, fluctuation profile matching, and the Wiener-Khintchine theorem are used to define the "time periods," t , for anharmonic principal components (PCs), which are validated by nuclear magnetic resonance (NMR) order parameters. The PCs with their respective "time periods" are mapped to the eigenvalues (λ ENM) of the corresponding ENM modes. Thus, the power laws t (ns) = 56.1λ ENM −1.6 and σ2(Å2) = 32.7λ ENM −3.0 can be established allowing the characterization of the timescales of NMR-resolved conformers, crystallographic anisotropic displacement parameters, and important ribosomal motions, as well as motional sizes of the latter. • Defined timescales for modes of protein motions observed in a long MD simulation • Providing a timescale to experimentally observed protein fluctuation data • Mapping timescales and variances obtained from MD to a simple elastic network model • Establish two power laws relating the absolute timescale/variance with ENM modes Biological processes are often governed by protein functional dynamics that correspond to the large conformational transition and long timescales that cannot be practically studied using current simulation methodologies. We instead use the elastic network model (ENM), an efficient spring-bead model, and calibrate its predicted timescale and size of protein conformational changes with all-atom simulation data, resulting in time and space power laws with the only input being the ENM eigenvalues. [ABSTRACT FROM AUTHOR]