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Despite significant improvement in therapeutic development in the past decades, breast cancer remains a formidable cause of death for women worldwide. The hormone positive subtype (HR(+)) (also known as luminal type) is the most prevalant category of breast cancer, comprising ~70% of patients. The clinical success of the three CDK4/6 inhibitors palbociclib, ribociclib, and abemaciclib has revolutionized the treatment of choice for metastatic HR(+) breast cancer. Accumulating evidence demonstrate that the properties of CDK4/6 inhibitors extend beyond inhibition of the cell cycle, including modulation of immune function, sensitizing PI3K inhibitors, metabolism reprogramming, kinome rewiring, modulation of the proteosome, and many others. The ubiquitin-proteasome pathway (UPP) is a crucial cellular proteolytic system that maintains the homeostasis and turnover of proteins.We performed transcriptional profiling of the HR(+) breast cancer cell lines MCF7 and T47D treated with Palbociclib. Differential expressed genes were analyzed for novel pathways enriched. The results were further validated with biochemical assays and with real world clinical database cohorts.We uncovered a novel mechanism that demonstrate the CDK4/6 inhibitors suppress the expression of three ubiquitin conjugating enzymes UBE2C, UBE2S, UBE2T. Further validation in the HR(+) cell lines show that Palbociclib and ribociclib decrease UBE2C at both the mRNA and protein level, but this phenomenon was not shared with abemaciclib. These three E2 enzymes modulate several E3 ubiquitin ligases, including the APC/C complex which plays a role in G1/S progression. We further demonstrate the UBE2C/UBE2T expression levels are associated with breast cancer survival, and HR(+) breast cancer cells demonstrate dependence on the UBE2C.Our study suggests a novel link between CDK4/6 inhibitor and UPP pathway, adding to the potential mechanisms of their clinical efficacy in cancer.

Activation of EGFR and the NF-κB pathway in cetuximab-resistant cells

S1A: S1A: Gene expression profile of OECM1-CtxR cells (1.5 folds, 1955 identities); S1B: Cetuximab resistance signature (170 identities); S1C:Gene expression profiles in FaDu-Snail cells (2.5 folds with FPKM>1, 477 genes)

Purpose: In head and neck squamous cell carcinoma (HNSCC), the incidence of RAS mutation, which is the major cause of cetuximab resistance, is relatively rare compared with the other types of cancers, and the mechanism mediating acquired resistance is unclear compared with the driver gene mutation–mediated de novo resistance. Here, we investigated the driver gene mutation–independent mechanism for cetuximab resistance in HNSCC.Experimental Design: We used the in vitro-selected and in vivo-selected cetuximab-resistant sublines of HNSCC cell lines for investigating the mechanism of acquired resistance to cetuximab. Zebrafish model was applied for evaluating the synergistic effect of combinatory drugs for overcoming cetuximab resistance.Results: The cetuximab-resistant HNSCC cells undergo a Snail-induced epithelial–mesenchymal transition. Mechanistically, Snail induces the expression of lymphotoxin-β (LTβ), a TNF superfamily protein that activates NF-κB, and protein arginine methyltransferase 1 (PRMT1), an arginine methyltransferase that methylates EGFR. LTβ interacts with methylated EGFR to promote its ligand-binding ability and dimerization. Furthermore, LTβ activates the NF-κB pathway through a LTβ receptor–independent mechanism. Combination of an EGFR tyrosine kinase inhibitor and a NF-κB inhibitor effectively suppressed cetuximab-resistant HNSCC and interfering with the EGFR–LTβ interaction reverses resistance.Conclusions: Our findings elucidate the mechanism of driver gene mutations–independent mechanism of acquired resistance to cetuximab in HNSCC and also provide potential strategies for combating cetuximab resistance. Clin Cancer Res; 23(15); 4388–401. ©2017 AACR.

Includes legends to 5 supplementary figures, supplementary methods, and supplementary references

High-entropy-alloy (HEA) nanocrystals consisting of a minimum of five elements have recently emerged as a versatile family of catalysts due to immense chemical space and tunability1-3. However, there are no effective strategies for synthesizing libraries of HEA nanocrystals with controlled surface atomic structures of exposed facets for boosting catalytic performance4-19. Due to the distinct nucleation and growth kinetics of constituent metals and their distinctive crystal structures, it is incredibly challenging to confine five or more different metal species situated on the nanocrystal surface with a specific arrangement but also in a high-entropy random mixing state. Here we present a straightforward strategy to craft a library of facet-controlled HEA nanocrystals with up to ten dissimilar metallic elements (Pt, Pd, Ir, Ru, Rh, Os, Au, Fe, Co, and Ni) by solution-phase layer-by-layer epitaxial growth, enabling the design of 638 distinct catalysts with 5 to 10 elements in equimolar ratios. The subnanometer-thick solid-solution HEA atomic layers can be deposited epitaxially on nanocrystal seeds with {100} and {111} facets, thus achieving HEA shells with square and hexagonal atomic arrangements, respectively. The hollow HEA nanocages with ultrathin walls along a specific direction can be further fabricated via post-synthetic chemical etching. Three facet-dependent catalytic actives of HEA nanocrystals are discovered in electrocatalysis and photocatalysis, and their catalytic facets with real active sites are also identified by in situ synchrotron X-ray absorption spectroscopy and density-functional theory calculations. Our work enables facet engineering in the multi-elemental space and unveils the critical needs for their future development toward catalysis.

VO2 thin films are fabricated by the reactive high power impulse magnetron sputtering technique. Their thermochromic properties are found to be greatly affected by the addition of nitrogen during the deposition process. These include an effect of localized surface plasmon resonance due to isolated island structures. Furthermore, low transition temperatures below 45 °C are observed due to oxygen-deficient conditions. Also, the transition temperature decreases with an increase in the thickness of the TiO2 buffer layer. The reduction in transition temperature could be as low as 39 °C with a solar modulating ability of 4% at a thicker buffer of 300 nm under a high gas ratio of 21.7% for nitrogen. The crystalline phase is identified by x-ray diffraction, showing that the intensity of monoclinic crystallites at a diffraction angle of 2θ = 27.8° for (011) phase decreases with an increase in the amount of nitrogen, whereas a relaxing shift is detected near the diffraction angle of 2θ = 37.0° for [Formula: see text] phase. Similar behavior is seen in the peak shift of the (004) phase for TiO2. The d-spacing of the crystallization phase with island structure is identified by high-resolution transmission electron microscopy. The evolution of stress release, which is strongly dependent on surface morphology, is consistent with x-ray pole figure representation. The visible transmittance and solar modulation ability as functions of the amount of nitrogen and the buffer thickness of TiO2 are discussed.

Alizarin (1,2-dihydroxyanthraquinone) is a natural red dye extracted from the roots of Rubia cordifolia L. (family Rubiaceae). Alizarin has been used as a biological red stain for calcium. The aryl hydrocarbon receptor (AhR) has critical roles in multiple physiological pathways. This study aimed to determine whether alizarin is an unreported ligand of AhR. In the present study, we investigated the effects on cytochrome P450 (CYP) 1A1 mRNA, protein expression, AhR nuclear translocation, aryl hydrocarbon response element (AHRE) reporter activity, and AhR-specific antagonist following alizarin treatment of cells of the human hepatoma cell line, HepG2, and murine hepatoma cell line, Hepa-1c1c7. Alizarin induced CYP1A1 mRNA and protein expression in HepG2 and Hep-1c1c7 cells. Such induction was not present in C4 (B13NBii1) cells, which are AhR signal deficient, C12 (B15ECiii2) cells, which reduce AhR protein levels. The alizarin-induced responses were blocked by CH-223191, which is an AhR antagonist. Alizarin, the same as with the AhR ligand, induced the nuclear localization of AhR, as well as stimulated the transcriptional activity of AHRE. The results of this study suggest that alizarin is an AhR agonist.

Breast cancer is one of the most common cancers and a leading cause of death in women worldwide. Among these subtypes, triple negative breast cancer (TNBC) has the worst prognosis, with a dismal outcome especially in metastatic disease. Metastatic TNBC treated with conventional chemotherapy has a median overall survival (OS) of ~ 18 months. The addition of checkpoint inhibitors extend the median OS to more than 2 years in PD-L1 positive patients, but ultimately most patients succumb to the disease. Currently TNBC still poses as a clinical unmet need, and further understanding of the cancer biology may shed light in improving therapeutics against this deadly disease. Apoptosis, or programmed cell death, is a crucial function for cell homeostasis. The ability to evade or circumvent apoptosis is an important hallmark of cancer cells. X-linked ectodermal dysplasia receptor (XEDAR), a cell membrane receptor that binds to the pro-apoptotic ligand EDA-A2, is a member of the TNF receptor family and has been reported to be downregulated in breast cancer cells. XEDAR has been shown to induce downstream apoptosis by binding to EDA-A2, by a mechanism similar to extrinsic apoptotic pathway. By interrogating clinical databases and cross comparison using TCGA, CCLE, and other breast cancer datasets, we discover XEDAR as substantially downregulated in TNBC. Transcription profile analysis between different XEDAR expressing profiles uncovered novel pathways that could be potentially targeted for TNBC treatment. RNA-seq profiling in XEDAR overexpressing TNBC cells were cross compared with aforementioned discovered pathways. Vulnerable pathways including angiogenesis were discovered as possible therapeutic targets. As a proof of concept, we combined angiogenesis inhibitors with EDA-A2 ligand treatment in XEDAR overexpression TNBC cells and observed synergistic effects for combination. Our study uncover XEDAR as a potential target for further treatment in TNBC, which remains to be further validated in preclinical and clinical studies. Citation Format: Chih-Yi Lin, Chung-Jen Yu, Chih-Yang Wang, Kai-Jun Liu, Jiun-I Lai. Characterization the mechanistic role of the proapoptotic receptor XEDAR and its therapeutic potential in TNBC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5651.

In response to the rapid development of science and technology in recent years and the enthusiasm for cultivating popular aesthetics, the emphasis on cultivating problem-solving abilities and integrating STEAM education in practical applications in various fields has become a trend of promotion today.

Sorafenib is an orally administered inhibitor of several tyrosine protein kinases. Treatment with sorafenib induces autophagy, which may suppress the growth of hepatocellular carcinoma (HCC) and other cancers. Aryl hydrocarbon receptor (AhR) is activated by xenbiotics and is involved in detoxification, but also plays other physiological roles. The following results were obtained. ITE and β-NF are endogenous and synthetic AhR ligands, respectively. One μM sorafenib can strongly suppress baseline as well as 0.5 μM ITE- and 1 μM β-NF-induced transcriptional activity of the aryl hydrocarbon response element (AHRE) in both human and mouse cells. Cytochrome p450 (CYP) 1A1 is mainly transcribed by activated AhR. Sorafenib (2-15 μM) strongly and dose-dependently suppressed baseline as well as 2 μM ITE- and 10 μM β-NF-induced CYP1A1 mRNA and protein expression. Ligand-activated AhR translocates from the cytoplasm to the nucleus. While sorafenib was found to suppress AhR activity, the drug alone was able to induce AhR translocation into the nucleus. Sorafenib's antagonistic action on AhR was comparable to that of the known AhR antagonist CH-223191 in human liver and ovarian cell lines. In summary, we demonstrate that sorafenib is a potent AhR antagonist and likely endocrine disruptor of the AhR. Moreover, sorafenib offers potential benefit for diseases treatable through AhR suppression strategies. Further investigation is warranted into sorafenib's AhR antagonistic behavior.

Hutchinson–Gilford progeria syndrome (HGPS) is caused by the accumulation of mutant prelamin A (progerin) in the nuclear lamina, resulting in increased nuclear stiffness and abnormal nuclear architecture. Nuclear mechanics are tightly coupled to cytoskeletal mechanics via lamin A/C. However, the role of cytoskeletal/nuclear mechanical properties in mediating cellular senescence and the relationship between cytoskeletal stiffness, nuclear abnormalities, and senescent phenotypes remain largely unknown. Here, using muscle‐derived mesenchymal stromal/stem cells (MSCs) from the Zmpste24 −/− (Z24 −/−) mouse (a model for HGPS) and human HGPS fibroblasts, we investigated the mechanical mechanism of progerin‐induced cellular senescence, involving the role and interaction of mechanical sensors RhoA and Sun1/2 in regulating F‐actin cytoskeleton stiffness, nuclear blebbing, micronuclei formation, and the innate immune response. We observed that increased cytoskeletal stiffness and RhoA activation in progeria cells were directly coupled with increased nuclear blebbing, Sun2 expression, and micronuclei‐induced cGAS‐Sting activation, part of the innate immune response. Expression of constitutively active RhoA promoted, while the inhibition of RhoA/ROCK reduced cytoskeletal stiffness, Sun2 expression, the innate immune response, and cellular senescence. Silencing of Sun2 expression by siRNA also repressed RhoA activation, cytoskeletal stiffness and cellular senescence. Treatment of Zmpste24− / − mice with a RhoA inhibitor repressed cellular senescence and improved muscle regeneration. These results reveal novel mechanical roles and correlation of cytoskeletal/nuclear stiffness, RhoA, Sun2, and the innate immune response in promoting aging and cellular senescence in HGPS progeria., There is increased RhoA activation and cytoskeleton stiffness in progeria cells, which mediates increased nuclear blebbing, micronuclei formation, innate immune response, and cellular senescence. RhoA activation is coupled with elevated Sun2 expression, but not Sun1, especially in nucleus with blebbing and micronuclei. Repression of RhoA and Sun2 activation was able to reduce cytoskeleton stiffness, nuclear blebbing, and micronuclei formation and delay the progression of cellular senescence.

Pouring hot drinks is more challenging for the visually impaired and is challenging to determine the exact level of the water inside. This paper presents the design and development of an assistive device to assist the visually impaired handle hot liquids safer. In the proposed system, a cup holder developed that measures the water level and temperature through the use of various sensors. A cup prototype was designed using CAD and printed for further testing. The team has successfully developed a working prototype that determines water level through pressure and provides a warning to the user when the water is too hot. In the future, further tests will be done to allow various types of cups on the cupholder.

The purpose of this study is to explore the teaching of learning Japanese syllabary scaffolding, which is easy to use when applied to mobile games. Therefore, this study first collected literature data from the past, worked out a set of teaching scaffolds, and developed a mobile game so that the two could be combined with each other and use the SUS scale test to allow users to fill in, so as to obtain a conclusion as to whether the system was useful or not.

This research aims to establish a rotating electrical machinery failure decision-making system based on fuzzy theory and combine with the characteristics of electric and vibration signals to achieve a more comprehensive omen diagnosis of rotating electrical machinery. First of all, voltage and current signals are calculated through pointer to draw into a two-dimensional characteristic diagram so as to find failure characteristics from the relationship between imbalance rate and harmonic distortion, then shaft orbit diagram is mapped through vibration signals and fractal theory is used to extract characteristic parameters of orbit so as to find failure characteristics of mechanical vibration; based on this, fuzzy theory is used to integrate the expert knowledge and a complex failure decision-making system with electrical and vibration analysis technology is designed. This research develops four common failure models and a normal model for experiment and analysis, and it is known from the results that the failure diagnosis performance is not ideal with separate electric or vibration test method, which can only distinguish a few types of failures, but if it is combined with fuzzy failure decision-making system, it will have very excellent diagnosis performance, which can accurately distinguish failure problems of the experimental models to make the rotating electrical machinery have more complete failure prediction ability and it can effectively detect anomaly characteristics in the case of failure symptoms in order to avoid more serious accidents, and it also verifies the feasibility and effectiveness of hybrid failure diagnosis system proposed in this research. In-depth research will be continued in future to explore more physical signals and its analysis methods so as to establish a more reliable rotation machine failure decision-making system to make lots of factories using rotating electrical machinery to have intelligent production capacity, and long-term operation of important units can obtain more reliable security guarantee.

Purpose: In head and neck squamous cell carcinoma (HNSCC), the incidence of RAS mutation, which is the major cause of cetuximab resistance, is relatively rare compared with the other types of cancers, and the mechanism mediating acquired resistance is unclear compared with the driver gene mutation–mediated de novo resistance. Here, we investigated the driver gene mutation–independent mechanism for cetuximab resistance in HNSCC. Experimental Design: We used the in vitro-selected and in vivo-selected cetuximab-resistant sublines of HNSCC cell lines for investigating the mechanism of acquired resistance to cetuximab. Zebrafish model was applied for evaluating the synergistic effect of combinatory drugs for overcoming cetuximab resistance. Results: The cetuximab-resistant HNSCC cells undergo a Snail-induced epithelial–mesenchymal transition. Mechanistically, Snail induces the expression of lymphotoxin-β (LTβ), a TNF superfamily protein that activates NF-κB, and protein arginine methyltransferase 1 (PRMT1), an arginine methyltransferase that methylates EGFR. LTβ interacts with methylated EGFR to promote its ligand-binding ability and dimerization. Furthermore, LTβ activates the NF-κB pathway through a LTβ receptor–independent mechanism. Combination of an EGFR tyrosine kinase inhibitor and a NF-κB inhibitor effectively suppressed cetuximab-resistant HNSCC and interfering with the EGFR–LTβ interaction reverses resistance. Conclusions: Our findings elucidate the mechanism of driver gene mutations–independent mechanism of acquired resistance to cetuximab in HNSCC and also provide potential strategies for combating cetuximab resistance. Clin Cancer Res; 23(15); 4388–401. ©2017 AACR.

In this study, the electroless plating has been successfully applied for nickel catalyst layer and the multiwall carbon nanotubes (MWNTs) grown by chemical vapor deposition (CVD). Sulfuric acid solution was used as buffer to adjust and maintain pH value of electroless plating solution on 4.5. The structural, element, and quality of MWNTs were investigated with field emission scanning electron microscope (FE-SEM), X-ray diffraction patterns (XRD), energy dispersive spectrometer (EDS) and Raman spectrometer. From the FE-SEM image, it showed that the density of MWNTs increased as the deposition time of nickel catalyst layer increased. This result caused by the formation of nickel nucleation become rich as the immersion of the substrate in electroless plating solution was longer, and this benefited the growth of carbon nanotubes. The Raman analysis demonstrated that the ID/IG ratio of MWNTs decreases as the deposition times of nickel catalyst layer increases, indicating that more graphene MWNTs structures were formed.

Taiwan EPA has promulgated Resource Recycling Act in 2002, which is formulated to conserve natural resources, reduce waste, promote recycling and reuse of materials, mitigate environmental loading, and build a society in which resources are used in a sustainable manner. [1] Since 1998, the recycling of waste large household appliances such as televisions, washing machines, refrigerators, and air conditioners, etc. has been implemented; waste electric fans and waste computer keyboards were also included in 2007. Although recycling in Taiwan initiated early, whether waste electrical and electronic equipment recycling is just the process of decomposition, recycling, incineration, and landfill, rather than extending the product lifespan, need further studies to confirm that. The Recycling Fund Management Board takes charge of the operation of recycling mechanism in Taiwan. The funds mostly paid by the businesses as the recycling, clearance and disposal fees. Such fees now are unified under the same products specifications. The existed system can’t provide products under the same specifications but with longer lifespan more preferential fees, which means that there is no incentive for the suppliers to improve the design of products. With Radio Frequency Identification (RFID) inserted in, the household appliances will not only have the basic information about the product, but also can keep track of the purchase and maintenance record, as well as the disposal date and location, during the use stage of that product. Such record provides information on the service life of the product, and the recycling fees paid by businesses could be returned relative to the lifetime to the consumers accordingly. The new mechanism incentives the suppliers to consider the product durability in design and manufacture stages that helps achieve the goal to make products decomposable, recyclable, and lifetime extended.

The molten pool shape and transport variables induced by thermocapillary force during welding (or melting) of workpieces, such as pure iron, titanium, high speed steel and stainless steel alloys, can be self-consistently predicted from scale analysis. Determination of the molten pool shape and transport variables is crucial due to their close relationship with the microstructures, strength and properties of the fusion zone. In this study, the pool excludes a strongly wavy bottom and the surface velocity profile has two peaks valid for Prandtl numbers lying between 0.3 and unity. The surface tension coefficient is negative and suitable for all pure liquid metals and alloys containing minor surface active solutes, giving rise to an outward surface flow. In view of high Marangoni number, the domain of scaling is divided into the hot and cold corner regions, boundary layers on the solid–liquid interface and ahead of the melting front. The results find that the width and depth of the pool, peak and secondary peak surface velocities, and maximum temperatures in the hot and cold corner regions can be explicitly and separately determined as functions of working variables, or Marangoni, Prandtl, Peclet, Stefan, and beam power numbers and solid-to-liquid thermal conductivity ratio. The scaled results agree with numerical data and available experimental data. This work has academic and practical importance. Successful scaling not only reveals physical mechanisms, but also provides quantitative predictions of the fusion zone shapes and transport variables prior to melting or welding.

Critical heat flux (CHF) and pressure drop of subcooled flow boiling are measured for a microchannel heat sink containing 75 parallel 100 μm × 200 μm structured surface channels. The heated surface is made of a Cu metal sheet with/without 2 μm thickness diamond film. Tests and measurements are conducted with de-ionized water, de-ionized water +1 vol.% MCNT additive solution, and FC-72 fluids over a mass velocity range of 820–1600 kg/m2 s, with inlet temperatures of 15(8.6)°C, 25(13.6)°C, 44(24.6)°C, and 64(36.6)°C for DI water (FC-72), and heat fluxes up to 600 W/cm2. The CHF of subcooled flow boiling of the test fluids in the microchannels is measured parametrically. The two-phase pressure drop is also measured. Both CHF and the two-phase friction factor correlation for one-side heating with two other side-structured surface microchannels are proposed and developed in terms of the relevant parameters.

The effects of Prandtl number on two-dimensional thermocapillary convection and molten pool shape induced by negative surface tension coefficient in welding or melting with a time-dependent and distributed incident flux are numerically predicted in this study. This work is also applicable for predicting the quasi-steady three-dimensional thermocapillary convection. In this model, the time-dependent incident flux is specified as a function of scanning speed and energy distribution parameter. The computed flow patterns and molten pool shapes under the flat free surface are found to have distinct regions for different Marangoni and Prandtl numbers. Prandtl number indicates the thickness ratio between momentum and thermal boundary layers, whereas Marangoni number with negative surface tension coefficient induces an outward surface flow. Rather than the enhanced pool depth resulted from melting from an induced vortex cell near the bottom in the case of Prandtl number much less than unity, the molten pool shape for Prandtl number much greater than unity can produce a thin and narrow edge. The variations of Peclet number and dimensionless beam power with flow and temperature fields and fusion zone shapes are similar. The dimensionless peak surface speed versus product of Marangoni and Prandtl number, which involve predicted peak speed and temperature and molten pool width on the surface, agree with scale analysis and experimental data provided in the literature.

Experiments were performed to study the heat transfer characteristics of channel flows of deionized (DI) water, methanol, 50 wt% DI water/50 wt% methanol mixture, and ethanol solution in asymmetrically (one sided heating) heated rectangular microchannels with an aspect ratio (H/W) of 0.56 and the corresponding hydraulic diameters ( D ) of 129 μm at 5 ⩽ Re ⩽ 240. Local heat transfer coefficients distribution were recorded with both isothermal (273 K) and isoflux (12.6, 18.1, 32.3, 50.5 mW/mm 2 ) heating. The influences of test liquid mass flow rates, test fluids, heating condition (isothermal vs isoflux), and surface condition (hydrophilic vs hydrophobic) on heat transfer behavior were examined. Thermal entrance length were also found and correlated in terms of the relevant parameters.

Carbendazim inhibits microtubule assembly, thus blocking mitosis and inhibiting cancer cell proliferation. Accordingly, carbendazim is being explored as an anticancer drug. Data show that carbendazim increased mRNA and protein expressions and promoter activity of CYP1A1. In addition, carbendazim activated transcriptional activity of the aryl hydrocarbon response element, and induced nuclear translocation of the aryl hydrocarbon receptor (AhR), a sign the AhR is activated. Carbendazim-induced CYP1A1 expression was blocked by AhR antagonists, and was abolished in AhR signal-deficient cells. Results demonstrated that carbendazim activated the AhR, thereby stimulating CYP1A1 expression. In order to understand whether AhR-induced metabolic enzymes turn carbendazim into less-toxic metabolites, Hoechst 33342 staining to reveal carbendazim-induced nuclear changes and flow cytometry to reveal the subG0/G1 population were applied to monitor carbendazim-induced cell apoptosis. Carbendazim induced less apoptosis in Hepa-1c1c7 cells than in AhR signal-deficient Hepa-1c1c7 mutant cells. Pretreatment with β-NF, an AhR agonist that highly induces CYP1A1 expression, decreased carbendazim-induced cell death. In addition, the lower the level of AhR was, the lower the vitality present in carbendazim-treated cells, including hepatoma cells and their derivatives with AhR RNA interference, also embryonic kidney cells, bladder carcinoma cells, and AhR signal-deficient Hepa-1c1c7 cells. In summary, carbendazim is an AhR agonist. The toxicity of carbendazim was lower in cells with the AhR signal. This report provides clues indicating that carbendazim is more potent at inducing cell death in tissues without than in those with the AhR signal, an important reference for applying carbendazim in cancer chemotherapy.

An experimental and theoretical study of low Reynolds number compressible gas flow in a microchannel is presented. Nitrogen gas was used. The channel was microfabricated on an oxidized silicon wafer and was 50 μm deep, 200 μm wide and 24,000 μm long. The Knudsen number ranged from 0.001 to 0.02. Pressure drop at inlet and exit of the channel were measured and friction factor constant ratios were calculated at different mass flow rates in terms of Re. The results were found in good agreement with those predicted by analytical solutions in which a 2-D continuous flow model with first slip boundary conditions are employed and solved by a perturbation method with a proposed new complete momentum accommodation coefficient σ. Consequently, using slip boundary conditions, one can well predict the mass flow rate as well as inlet/exit pressure drop and friction factor constant ratio for a three-dimensional physical system.

This study proposes a music linkage jukebox system that recommends listeners a ranked list retrieved by the resemblance of music-induced emotions between the query clip and music bank. The retrieval results also provide a time-varying interface of dynamic emotional transition caused by music in a predetermined emotion plane. In the system, the multi-theme phrases of musical structure, including Intro, Verse, and the Chorus are analyzed by autocorrelation function as an input test structure, then using feature-weighted scoring algorithms to analyze the ingredients of music emotion with five audio characteristics sets of the testing music clips. The similarity of emotions between music clips and music bank are measured by Euclidean distance algorithms. Preliminary evaluations of the system illustrate the novelty with the emotion ratios and the real-time emotion locus evoked by music clips. The proposed system also shows the rapid browsing in the process for emotion similarity of music retrieval.

The molten pool shape and thermocapillary convection during melting or welding of metals or alloys are self-consistently predicted from scale analysis. Determination of the molten pool shape and transport variables is crucial due to their close relationship with the strength and properties of the fusion zone. In this work, surface tension coefficient is considered to be negative, indicating an outward surface flow, whereas high Prandtl number represents a reduced thickness of the thermal boundary layer compared to that of the momentum boundary layer. Since the Marangoni number is usually very high, the domain of scaling is divided into hot, intermediate and cold corner regions, boundary layers along the solid‐liquid interface and ahead of the melting front. The results show that the width and depth of the pool, peak and secondary surface velocities, and maximum temperatures in the hot and cold corner regions can be explicitly and separately determined as functions of working variables, or Marangoni, Prandtl, Peclet, Stefan, and beam power numbers. The scaled results agree with numerical results and available experimental data. [DOI: 10.1115/1.4005206]

This study presents a numerical scenario for the effect of thermocapillary convection on the transient, two-dimensional molten pool shape during welding or melting. Tracing the melting process is necessary to achieve a better and more complete understanding of the physical mechanism of welding. This model is used to simulate a steady state, three-dimensional welding process, by introducing an incident flux with a Gaussian distribution with a time-dependent radius determined by scanning speed and distribution parameter. Aside from presenting the variations of peak surface velocities and temperature, and depth and width of the molten pool with time, the predicted results of this work show that surface velocity and temperature profiles for a high Prandtl number strongly deform in the course of melting. The velocity profile eventually exhibits two peaks, located near the edges of the incident flux and the pool, respectively. Conversely, only one peak velocity occurs near the pool edge for a small Prandtl number. In all cases, surface temperature can ultimately be divided into hot, intermediate, and cold regions. The pool becomes deep due to an induced secondary vortex cell near the bottom of the pool for a small Prandtl number. For a high Prandtl number, the pool edge is thin and shallow, as a result of penetration into the solid near the top surface. The predicted results agree with those obtained using a commercial computer code.

The molten pool shape and thermocapillary convection during melting or welding of metals or alloys are self-consistently predicted from parametric scale analysis for the first time. Determination of the molten pool shape is crucial due to its close relationship with the strength and properties of the fusion zone. In this work, surface tension coefficient is considered to be negative values, indicating an outward surface flow, whereas high Prandtl number represents the thermal boundary layer thickness to be less than that of momentum. Since Marangoni number is usually very high, the scaling of transport processes is divided into the hot, intermediate and cold corner regions on the flat free surface, boundary layers on the solid-liquid interface and ahead of the melting front. Coupling among distinct regions and thermal and momentum boundary layers, the results find that the width and depth of the pool can be determined as functions of Marangoni, Prandtl, Peclet, Stefan, and beam power numbers. The predictions agree with numerical computations and available experimental data.Copyright © 2011 by ASME

In this study, the peak surface velocity driven by thermocapillary force in melting or welding pool irradiated by a distributed low-power-density beam is determined from a scale analysis. In view of different distances of diffusion between momentum and energy, the effects of Prandtl number on surface velocity are of interest. A low-power-density-beam heating implies no deep and narrow cavity (or keyhole) taking place in the pool. The results find that the peak surface velocity is proportional to the first power and 2/3 power of the surface tension coefficient or Marangoni number for high and low Prandtl number, respectively. The free surface velocity is determined by Prandtl and Marangoni numbers for given dimensionless beam power and Peclet numbers. The predictions agree with numerical computations.Copyright © 2011 by ASME

Completely stretched DNA molecules are becoming an important topic to advance our fundamental understanding of the physical and biological properties of DNA. In this study, λ phage DNA molecules are stretched on multi-walled carbon nanotube (MWCNT) films on the wall surfaces in a microchannel and measured through the total internal reflection fluorescence microscopy visualization/measuring technique. With DNA stretching in a definite direction, it is expected that a higher stretch ratio will be obtained. Real-time images show that the stretch ratio of the λ phage DNA molecules on the MWCNT walls reaches about 0.7 (relative to its contour length) at a low electrical field strength of 5 kV m−1, which is significantly higher than without the MWCNT-deposited film. Special attention is paid to the effect of the MWCNT film thickness, the channel size, in terms of the aspect ratio of the channel cross-section and channel length, and different electrical field strengths.

This work presents a testable design method for the embedded cores in an object SoC chip. Instead of modifying the digital cores for testability consideration, we target on revising the AMBA bus for test application and response observation. The test information is transformed from a core's I/Os to the chip's external pins. Experimental results on some embedded cores have shown that the proposed method costs small area and timing overhead.

An experimental and theoretical study of low Reynolds number compressible gas flow in a micro channel is presented. Nitrogen gas was used. The channel was microfabricated on silicon wafers and were 50 μm deep, 200 μm wide and 24000 μm long. The Knudsen number ranged from 0.001 to 0.02. Pressure drop were measured at different mass flow rates in terms of Re and found in good agreement with those predicted by analytical solutions in which a 2-D continuous flow model with first slip boundary conditions are employed and solved by perturbation methods.Copyright © 2003 by ASME

Experiments are performed to investigate subcooled flow boiling, on side wall cavities with angles of 60°, 90° and 120° with bottom-wall asymmetrical heating, for a microchannel heat sink containing 75 parallel 100 µm × 200 µm channels. The heated surface is made of a Cu metal sheet with/without 2 µm thickness diamond film. Tests and measurements are conducted with de-ionized water, de-ionized water + 1 vol.% MCNT additive solution, FC-72 fluids over a mass velocity range of 820–1600 kg m−2 s, inlet temperatures of 15 (8.6), 25 (13.6), 44 (24.6) and 64 °C (36.6 °C) for DI water (FC-72) and heat fluxes up to 800 W cm−2. Flow morphologies, boiling incipience, two-phase heat transfer coefficients and critical heat fluxes are obtained and presented. Both cavities' structured and sputtered diamond ultrathin film surfaces in nanofluid flow boiling in a microchannel are shown to significantly enhance heat transfer through the promotion of bubble ebullitions and to reduce boiling incipience. A significant increase in critical heat flux (CHF) is also found.

Experiments were performed using a microparticle image velocimetry (MPIV) for 2D velocity distributions of electroosmotically driven flows in a 40-mm-long microchannel with a square cross section of 200×200 μm. Electroosmotic flow (EOF) bulk fluid velocity measurements were made in a range of streamwise electric field strengths from 5 to 25 kV/m. A series of seed particle calibration tests can be made in a 200×120×24,000-μm untreated polydimethyl siloxane (PDMS channel incorporating MPIV to determine the electrophoretic mobilities in aqueous buffer solutions of 1× TAE, 1× TBE, 10 mM NaCl, and 10 mM borate. A linear/nonlinear (due to Joule heating) flow rate increase with applied field was obtained and compared with those of previous studies. A parametric study, with extensive measurements, was performed with different electric field strength and buffer solution concentration under a constant zeta potential at wall for each buffer. The characteristics of EOF in square microchannels were thus investigated. Finally, a composite correlation of the relevant parameters was developed in the form of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$u* = 5.46\;\varsigma {\kern 1pt} ^{{*0.739}} DN^{{ - 2.132}} ME^{{*0.9996}}_{x}$$\end{document} within ±1% accuracy for 99% of the experimental data.