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The gastrointestinal tract represents a complex and challenging environment for enterohemorrhagic Escherichia coli (EHEC). However, EHEC is a highly adaptable pathogen, requiring only 10 to 100 CFUs to cause infection.

ObjectiveTo investigate the effect of Hsp27 and the inhibitory effect of Atractylenolide I (ATL-1) on the proliferation of prostate cancer cell DU145 and PC-3.MethodsMTT assay was used to detect the inhibitory effect of silencing Hsp27 and ATL-1 on DU145 and PC-3 proliferation of prostate cancer cells. TUNEL detected the apoptosis rate of prostate cancer cell DU145 and PC-3 after silencing Hsp27 and ATL-1 treated. qRT-PCR was used to detect the changes of apoptosis related genes caspase-3, PARP, Bax and Bcl-2 in prostate cancer cell DU145 and PC-3 after the effect of silencing Hsp27 and ATL-1 treated. At the same time, the antitumor effect of ATL-1 combined with cabozantinib was analyzed.ResultsHsp27 was highly expressed in human prostate cancer. MTT assay showed that ATL-1 inhibited the proliferation of prostate cancer cells DU145 and PC-3 compared with the control group. TUNEL results showed that silencing Hsp27 and ATL-1 treated could significantly promote the apoptosis of prostate cancer cells DU145 and PC-3 compared with the control group. qRT-PCR results showed that compared with the control group, ATL-1 could promote the expression of caspase-3, PARP and Bax in DU145 and PC-3 prostate cancer cells. Inhibition of Hsp27 by ATL-1 reduced cell viability and induced apoptosis. ATL-1 inhibits the antitumor effect of Hsp27 - enhanced cabozantinib. Hsp27 regulates eIF4E and mediates cell protection.ConclusionSilencing Hsp27 inhibits EMT. ATL-1 can inhibit the malignant evolution of prostate cancer cells by inhibiting Hsp27/eIF4E. ATL-1 also enhanced chemosensitization of cabozantinib in prostate cancer.

The cuticle, a hydrophobic layer of cutin and waxes synthesized by plant epidermal cells, is the major barrier to water loss when stomata are closed. Dissecting the genetic architecture of natural variation for maize (Zea mays L.) leaf cuticular conductance (gc) is important for identifying genes relevant to improving crop productivity in drought-prone environments. To this end, we performed an integrated genome- and transcriptome-wide association studies (GWAS and TWAS) to identify candidate genes putatively regulating variation in leaf gc. Of the 22 plausible candidate genes identified, 4 were predicted to be involved in cuticle precursor biosynthesis and export, 2 in cell wall modification, 9 in intracellular membrane trafficking, and 7 in the regulation of cuticle development. A gene encoding an INCREASED SALT TOLERANCE1-LIKE1 (ISTL1) protein putatively involved in intracellular protein and membrane trafficking was identified in GWAS and TWAS as the strongest candidate causal gene. A set of maize nested near-isogenic lines that harbor the ISTL1 genomic region from eight donor parents were evaluated for gc, confirming the association between gc and ISTL1 in a haplotype-based association analysis. The findings of this study provide insights into the role of regulatory variation in the development of the maize leaf cuticle and will ultimately assist breeders to develop drought-tolerant maize for target environments.

Purpose: To investigate the effect of different extracts of Cremastra appendiculata (D. Don) Makino onapoptosis of A549 cells, and the underlying mechanism.Methods: The contents of colchicine in ethyl acetate and n-butanol extracts of Cremastra appendiculata(D. Don) Makino were determined using high performance liquid chromatography (HPLC). Lung cancerA549 cells cultured in vitro were divided into blank control, standard colchicine and Cremastra appendiculata (D. Don) Makino extract groups. The effect of different extract concentrations on proliferation of the cells was determined using methyl thiazolyl diphenyl-tetrazolium (MTT) assay, while apoptosis of A549 cells induced by the extracts was evaluated by flow cytometry (FC).Results: Compared with the standard colchicine group, there was no colchicine in the n-butanol and ethyl acetate extracts of Cremastra appendiculata. Results from MTT assay showed that the extract inhibited the proliferation of A549 cells (p < 0.05). Flow cytometry results showed that ethyl acetate extract significantly enhanced apoptosis in A549 cells (p < 0.05). However, n-butanol extract had no significant effect on the apoptosis of A549 cells (p < 0.05).Conclusion: The ethyl acetate extract of Cremastra appendiculata (D. Don) Makino induces apoptosis in lung cancer A549 cells. Therefore, there is a need for further research and development of antitumor drugs from the extract of Cremastra appendiculata (D. Don) Makino. Keywords: Cremastra appendiculata (D. Don) Makino, Colchicine, A549 cells, Apoptosis

Oxygen-terminated type IIa (OT-IIa) diamond with oxygen suspended in the form of a ketone bond (C O) was synthesized via acid treatment. The Fermi level at 3.23 eV below the conduction band minimum for the OT-IIa diamond surface was measured experimentally, while that at 0.97 eV for the bulk was calculated theoretically. An acceptor model of the surface states was developed, employed, and combined with an upward-bending band diagram to compensate this energetic band difference between the surface and bulk of OT-IIa diamond. A Schottky barrier height of 3.15 eV between gold and the OT-IIa diamond was also measured. In addition, we also inferred the downward-bending band diagram for the surface of oxygen-terminated p-type diamond doped with boron. This work complements the semiconductor theory concerning diamond and will be helpful to analyze and improve the performance of devices based on oxygen-terminated diamond.

Long non‑coding RNA growth arrest specific 5 (GAS5) exerts inhibitory effects through the modulation of several target microRNAs (miRs) in cancer. However, its potential roles and underlying relationship during colorectal cancer (CRC) progression are unclear. Therefore, we explored the role of the negative feedback loop formed by the GAS5/miR‑34a axis and mammalian target of rapamycin/sirtuin 1 (mTOR/SIRT1) pathway on macroautophagy and apoptosis in CRC. Expression of GAS5, miR‑34a, SIRT1 and mTOR in CRC patients and cell lines was detected by quantitative reverse transcription polymerase chain reaction. Online bioinformatic analysis was used to predict the downstream miRs of GAS5. Luciferase assay and western blotting were performed to demonstrate miR‑34a as a downstream target gene of GAS5 in CRC cells. The effects of the GAS5/miR‑34a axis on apoptosis, macroautophagy, and the mTOR/SIRT1 pathway were assessed by flow cytometry, transmission electron microscopy and western blotting, respectively. Our results suggested that GAS5 was downregulated and acted as a molecular sponge of miR‑34a during CRC progression. miR‑34a participated in regulating GAS5‑suppressed CRC cell macroautophagy and induced apoptosis through the mTOR/SIRT1 pathway. GAS5‑mediated macroautophagy was maintained in an equilibrium state that might have a protective effect on CRC cell apoptosis. The mTOR signaling pathway suppressed GAS5 expression and formed a negative regulation feedback loop with miR‑34a in CRC cells. Our results suggested that the GAS5/miR‑34a/SIRT1/mTOR negative regulatory feedback loop mediated CRC cell macroautophagy, and maintained the cells in an autonomous equilibrium state, but not excessive activation state, which functions as a strong antiapoptotic phenotype during human CRC progression.

Significance Plant cuticles provide barriers to water loss and arose as aquatic plants adapted to the dry terrestrial environment. The cuticle components, waxes and the fatty acid-based polymer cutin, are synthesized in the plant epidermis, exported across the cell wall, and deposited on the plant surface. This study suggests a role for PHYTOCHROME light receptors during cuticle development in leaves of maize and moss, diverse species that are separated by more than 400 million y of land plant evolution. We hypothesize that phytochrome-mediated light signaling contributed to the evolution of cuticles in land plants., Plant cuticles are composed of wax and cutin and evolved in the land plants as a hydrophobic boundary that reduces water loss from the plant epidermis. The expanding maize adult leaf displays a dynamic, proximodistal gradient of cuticle development, from the leaf base to the tip. Laser microdissection RNA Sequencing (LM-RNAseq) was performed along this proximodistal gradient, and complementary network analyses identified potential regulators of cuticle biosynthesis and deposition. A weighted gene coexpression network (WGCN) analysis suggested a previously undescribed function for PHYTOCHROME-mediated light signaling during the regulation of cuticular wax deposition. Genetic analyses reveal that phyB1 phyB2 double mutants of maize exhibit abnormal cuticle composition, supporting the predictions of our coexpression analysis. Reverse genetic analyses also show that phy mutants of the moss Physcomitrella patens exhibit abnormal cuticle composition, suggesting an ancestral role for PHYTOCHROME-mediated, light-stimulated regulation of cuticle development during plant evolution.

The cuticle, a hydrophobic layer of cutin and waxes synthesized by plant epidermal cells, is the major barrier to water loss when stomata are closed at night and under water-limited conditions. Elucidating the genetic architecture of natural variation for leaf cuticular conductance (gc) is important for identifying genes relevant to improving crop productivity in drought-prone environments. To this end, we conducted a genome-wide association study ofgcof adult leaves in a maize inbred association panel that was evaluated in four environments (Maricopa, AZ, and San Diego, CA in 2016 and 2017). Five genomic regions significantly associated withgcwere resolved to seven plausible candidate genes (ISTL1, two SEC14 homologs, cyclase-associated protein, a CER7 homolog, GDSL lipase, and β-D-XYLOSIDASE 4). These candidates are potentially involved in cuticle biosynthesis, trafficking and deposition of cuticle lipids, cutin polymerization, and cell wall modification. Laser microdissection RNA sequencing revealed that all these candidate genes, with the exception of the CER7 homolog, were expressed in the zone of the expanding adult maize leaf where cuticle maturation occurs. With direct application to genetic improvement, moderately high average predictive abilities were observed for whole-genome prediction ofgcin locations (0.46 and 0.45) and across all environments (0.52). The findings of this study provide novel insights into the genetic control ofgcand have the potential to help breeders more effectively develop drought-tolerant maize for target environments.Article summaryThe cuticle serves as the major barrier to water loss when stomata are closed at night and under water-limited conditions and potentially relevant to drought tolerance in crops. We performed a genome-wide association study to elucidate the genetic architecture of natural variation for maize leaf cuticular conductance. We identified epidermally expressed candidate genes that are potentially involved in cuticle biosynthesis, trafficking and deposition, cutin polymerization, and cell wall modification. Finally, we observed moderately high predictive abilities for whole-genome prediction of leaf cuticular conductance. Collectively, these findings may help breeders more effectively develop drought-tolerant maize.

In order to meet the high safety requirement of high-level automatic steering mechanism for commercial vehicle, a kind of steer-by-wire (SBW) system with redundant motors is studied in this paper, and the structure principle and control strategy of the system are studied. Commercial vehicles have the characteristics of large steering resistance moment, which is accompanied by impact and vibration during steering, so the synchronous control of dual motors is the key and difficult problem. Based on the circulating ball steering gear for commercial vehicle, dual-motor synchronous control architecture is designed and the dual-motor global-fast-terminal-sliding-mode (nonsingular-GFTSM) synchronous control is formulated. Compared with the sliding-mode control, the simulation results show that the dual-motor actuator based on nonsingular-GFTSM can better realize the synchronous operation in angle, speed and torque. In addition, a real-time motor fault-diagnosis method based on sliding mode observer and a fault-tolerant control strategy based on smooth switching system are designed, which can achieve fast fault-isolation and smooth torque switching in case of actuator failure in dual-motor system. A Hardware-in-the-Loop (HIL) test bench is built to further verify the effectiveness of the synchronous and fault-tolerance control strategy for dual motors.

Background and AimsPrior work has examined cuticle function, composition and ultrastructure in many plant species, but much remains to be learned about how these features are related. This study aims to elucidate relationships between these features via analysis of cuticle development in adult maize (Zea mays L.) leaves, while also providing the most comprehensive investigation to date of the composition and ultrastructure of adult leaf cuticles in this important crop plant.MethodsWe examined water permeability, wax and cutin composition via gas chromatography, and ultrastructure via transmission electron microscopy, along the developmental gradient of partially expanded adult maize leaves, and analysed the relationships between these features.Key ResultsThe water barrier property of the adult maize leaf cuticle is acquired at the cessation of cell expansion. Wax types and chain lengths accumulate asynchronously over the course of development, while overall wax load does not vary. Cutin begins to accumulate prior to establishment of the water barrier and continues thereafter. Ultrastructurally, pavement cell cuticles consist of an epicuticular layer, and a thin cuticle proper that acquires an inner, osmiophilic layer during development.ConclusionsCuticular waxes of the adult maize leaf are dominated by alkanes and alkyl esters. Unexpectedly, these are localized mainly in the epicuticular layer. Establishment of the water barrier during development coincides with a switch from alkanes to esters as the major wax type, and the emergence of an osmiophilic (likely cutin-rich) layer of the cuticle proper. Thus, alkyl esters and the deposition of the cutin polyester are implicated as key components of the water barrier property of adult maize leaf cuticles.

Bulliform cells comprise specialized cell types that develop on the adaxial (upper) surface of grass leaves, and are patterned to form linear rows along the proximodistal axis of the adult leaf blade. Bulliform cell patterning affects leaf angle and is presumed to function during leaf rolling, thereby reducing water loss during temperature extremes and drought. In this study, epidermal leaf impressions were collected from a genetically and anatomically diverse population of maize inbred lines. Subsequently, convolutional neural networks were employed to measure microscopic, bulliform cell-patterning phenotypes in high-throughput. A genome-wide association study, combined with RNAseq analyses of the bulliform cell ontogenic zone, identified candidate regulatory genes affecting bulliform cell column number and cell width. This study is the first to combine machine learning approaches, transcriptomics, and genomics to study bulliform cell patterning, and the first to utilize natural variation to investigate the genetic architecture of this microscopic trait. In addition, this study provides insight toward the improvement of macroscopic traits such as drought resistance and plant architecture in an agronomically important crop plant.

Plant epidermal cuticles are composed of hydrophobic lipids that provide a barrier to non-stomatal water loss, and arose in land plants as an adaptation to the dry terrestrial environment. The expanding maize adult leaf displays a dynamic, proximodistal gradient of cuticle development, from the leaf base to the tip. Recently, our gene co-expression network analyses together with reverse genetic analyses suggested a previously undescribed function for PHYTOCHROME-mediated light signaling during cuticular wax deposition. The present work extends these findings by identifying a role for a specific LIPID TRANSFER PROTEIN (LTP) in cuticle development, and validating it via transgenic experiments in Arabidopsis. Given that LTPs and cuticles both evolved in land plants and are absent from aquatic green algae, we propose that during plant evolution, LTPs arose as one of the innovations of land plants that enabled development of the cuticle.

Directly modulated 850-nm multimode vertical-cavity surface-emitting lasers (MM-VCSELs) with different oxide apertures and transmission microstrip lengths are compared on the transmission performance of the non-return-to-zero on-off keying (NRZ-OOK) and four-level pulse amplitude modulation (PAM-4) data formats. In this work, intrinsic and extrinsic responses of the MM-VCSEL are also discussed concurrently. By tuning the length of the transmission microstrip in VCSEL, the low reflection coefficient and the enhanced 3-dB modulation bandwidth are achieved. The inductance of the transmission microstrip in the series connection with the capacitance in the active region is optimized to reduce the power loss induced by imaginary impedance. The different oxide aperture sizes for MM-VCSEL are also studied to control the capacitance and photon density. More importantly, the 3-dB modulation bandwidth, impedance matching, slope efficiency, relative intensity noise (RIN), and mode partition noise (MPN) for the MM-VCSEL with various designs are discussed to determine the best device with the high-speed transmission capability. The optimal MM-VCSEL with a diameter of 7 µm oxide aperture and a length of 25 µm transmission microstrip successfully demonstrates 50-Gbit/s OOK and 84-Gbit/s PAM4 after using the pre-emphasis technique for future data-center applications.

The purpose of this study was to investigate the protective effect of catalpol on Lipopolysaccharide (LPS)/D-galactosamine (D-gal)-induced acute liver injury in mice. The mouse model was established by injection of LPS and D-gal. Catalpol (2.5, 5, 10 mg/kg) were pretreated intraperitoneally 1 h before LPS and D-gal. The survival rate, AST, ALT, MDA, MPO activity, hepatic tissue histology, TNF-α level, and NF-κB activation were assayed. The results revealed that catalpol dose-dependently elevated the survival rate. Furthermore, catalpol reduced the activities of AST, ALT, MDA, and MPO. The production of TNF-α was also inhibited by treatment of catalpol. In addition, catalpol inhibited LPS/D-gal-induced NF-κB activation. The expression of Nrf2 and HO-1 were up-regulated by treatment of catalpol. These results indicated that pretreatment with catalpol could attenuate LPS/D-gal-induced acute liver injury in mice and the underlying mechanism may due to the inhibition of NF-κB signaling pathway and the activation of Nrf2 signaling pathway.

The ability to continuously tune the wavelength of a laser is of critical importance and is a fundamental building block for many optical systems, including wavelength division multiplexed optical fiber communication systems. Vertical cavity surface emitting laser (VCSEL) structure offers a unique advantage to engineer the lasing wavelength because of its ultrashort cavity length, inherently supporting a single Fabry–Perot mode. Hence, a continuous change in VCSEL cavity thickness leads to a continuous sweep of VCSEL wavelength. Wavelength-tunable VCSELs have been a subject of intense interest for the last two decades. Incorporating part or entire top mirror of a VCSEL in an optical microelectromechanical structure (MEMS), continuous wavelength sweeps have been reported. The monolithic integration brings together the best of both technologies and leads to an unprecedented performance in the continuously swept wavelength range. In addition, with the advances of ultrathin high contrast gratings and metastructures (HCG/HCM), the wavelength tuning speed of MEMS-VCSELs has been increased to 1–10 MHz range. Such lasers, now referred as wavelength-swept lasers, are enabling new applications in optical coherent tomography and light detection and ranging systems. In this paper, we review various structures and recent progress of MEMS-VCSELs. We summarize some of the early breakthroughs in designs and properties of micromechanical tunable VCSELs, including advances in HCG/HCM-based MEMS-VCSELs emitting at 850, 1060, and 1550 nm wavelength regimes. In addition, we report a brand new design leading to a record high Δλ/λo = 6.9% tuning ratio with 600 kHz speed at center wavelength of 1060 nm.

On the demand of single-photon entangled light sources and high-sensitivity probes in the fields of quantum information processing, weak magnetic field detection and biosensing, the nitrogen vacancy (NV) color center is very attractive and has been deeply and intensively studied, due to its convenience of spin initialization, operation, and optical readout combined with long coherence time in the ambient environment. Although the application prospect is promising, there are still some problems to be solved before fully exerting its characteristic performance, including enhancement of emission of NV centers in certain charge state (NV- or NV0 ), obtaining indistinguishable photons, and improving of collecting efficiency for the photons. Herein, the research progress in these issues is reviewed and commented on to help researchers grasp the current trends. In addition, the development of emerging color centers, such as germanium vacancy defects, and rare-earth dopants, with great potential for various applications, are also briefly surveyed.

Plant cuticles are composed of wax and cutin, and evolved in the land plants as a hydrophobic boundary that reduces water loss from the plant epidermis. The expanding maize adult leaf displays a dynamic, proximodistal gradient of cuticle development, from the leaf base to the tip. Laser microdissection RNA Sequencing (LM-RNAseq) was performed along this proximodistal gradient, and complementary network analyses identified potential regulators of cuticle biosynthesis and deposition. Correlations between cuticle development and cell wall biosynthesis processes were identified, as well as evidence of roles for auxin and brassinosteroids. In addition, our network analyses suggested a previously undescribed function for PHYTOCHROME-mediated light signaling during cuticular wax deposition. Genetic analyses reveal that the phyB1 phyB2 double mutant of maize exhibits abnormal cuticle composition, supporting predictions of our coexpression analyses. Reverse genetic analyses also show that phy mutants of the moss Physcomitrella patens exhibit abnormal cuticle composition, suggesting a role for light-stimulated development of cuticular waxes during plant evolution.

Hollow core anti-resonant fiber (HARF) has found a handful applications in optical communications, nonlinear optics and high power delivery. The intrinsic property of the fiber also renders it an ideal candidate for biosensing, which has not been explored intensively. Herein, we demonstrate an optical fiber sensing platform, taking advantages of the state-of-the-art HARF technology and superior physicochemical properties of 2D material black phosphorus, for ultra-sensitive detection of bisphenol A (BPA) in blood and environmental samples. The specially designed HARF can not only achieve broadband transmission of light, but also confine light in the low refractive-index liquid core, ensuring maximum overlap of light and liquid core. Modification of the inner surface of HARF with 2D black phosphorus nanoflakes functionalized with fluorescently labeled BPA-specific aptamer provides a smart sensing interface enabling highly selective detection of BPA via measuring the fluorescence. The limit of detection is 1.69pM, which is more than two orders of magnitude enhancement compared to the conventional plate assay. The proposed assay is not interfered with the BPA analogues BPB and BPS. The long optical path with tight optical confinement greatly enhances the analyte-light interaction and improves the sensitivity of the sensing platform. The proposed sensing platform can be further developed for versatile applications.

Although extensive prior work has characterized cuticle composition, function, ultrastructure and development in many plant species, much remains to be learned about how these features are interrelated. Moreover, very little is known about the adult maize leaf cuticle in spite of its significance for agronomically important traits in this major crop. We analyzed cuticle composition, ultrastructure, and permeability along the developmental gradient of partially expanded adult maize leaves to probe the relationships between these features. The water barrier property is acquired at the cessation of cell expansion. Wax types and chain lengths accumulate asynchronously along the developmental gradient, while overall wax load does not vary. Cutin begins to accumulate prior to establishment of the water barrier and continues thereafter. Ultrastructurally, pavement cell cuticles consist of an epicuticular layer, a thin cuticle proper that acquires an inner, osmiophilic layer during development, and no cuticular layer. Cuticular waxes of the adult maize leaf are dominated by alkanes and wax esters localized mainly in the epicuticular layer. Establishment of the water barrier coincides with a switch from alkanes to esters as the major wax type, and the emergence of an osmiophilic (likely cutin-rich) layer of the cuticle proper.Higlight statementChemical, ultrastructural and functional analysis of cuticle development in partially expanded adult maize leaves revealed important roles for wax esters and an osmiophilic, likely cutin-rich, layer in protection from dehydration.

The wavelength tuning range of a tunable vertical-cavity surface-emitting laser (VCSEL) is strongly influenced by the design of the interface between the semiconductor cavity and the air cavity. A simplified model is used to investigate the origin of the dramatic differences in free spectral range (FSR) and tuning slope observed in semiconductor cavity dominant, extended cavity, and air cavity dominant VCSELs. The differences arise from the positioning of the resonant and antiresonant wavelengths of the semiconductor cavity with respect to the center wavelength. The air cavity dominant design is realized by designing an antiresonant semiconductor cavity, resulting in a larger tuning slope near the center of the tuning range and a wider FSR toward the edges of the tuning range. The findings from the simplified model are confirmed with the simulation of a full VCSEL structure. Using an air cavity dominant design, an electrically pumped laser with a tuning range of 68.38 nm centered at 1056.7 nm at a 550 kHz sweep rate is demonstrated with continuous wave emission at room temperature. This epitaxial design rule can be used to increase the tuning range of tunable VCSELs, making them more applicable in swept-source optical coherence tomography and frequency-modulated continuous-wave LIDAR systems.

The sophistication of gene prediction algorithms and the abundance of RNA-based evidence for the maize genome may suggest that manual curation of gene models is no longer necessary. However, quality metrics generated by the MAKER-P gene annotation pipeline identified 17,225 of 130,330 (13%) protein-coding transcripts in the B73 Reference Genome V4 gene set with models of low concordance to available biological evidence. Working with eight graduate students, we used the Apollo annotation editor to curate 86 transcript models flagged by quality metrics and a complimentary method using the Gramene gene tree visualizer. All of the triaged models had significant errors – including missing or extra exons, non-canonical splice sites, and incorrect UTRs. A correct transcript model existed for about 60% of genes (or transcripts) flagged by quality metrics; we attribute this to the convention of elevating the transcript with the longest coding sequence (CDS) to the canonical, or first, position. The remaining 40% of flagged genes resulted in novel annotations and represent a manual curation space of about 10% of the maize genome (~4,000 protein-coding genes). MAKER-P metrics have a specificity of 100%, and a sensitivity of 85%; the gene tree visualizer has a specificity of 100%. Together with the Apollo graphical editor, our double triage provides an infrastructure to support the community curation of eukaryotic genomes by scientists, students, and potentially even citizen scientists.

The behavior of a tunable VCSEL is governed by the resonances of a semiconductor cavity and an air cavity. By designing a semiconductor cavity which is antiresonant at the tuning center, the free spectral range is maximized at the edges of the tuning range.

Colorectal cancer (CRC) is among the most common malignancies of the digestive system. Dysregulation of miRNAs and the farnesoid X receptor (FXR) are involved in the progression of CRC. In the present study, the effects of FXR and miR‑135A1 in CRC were evaluated. Reverse transcription quantitative‑polymerase chain reaction (RT‑qPCR) was used to examine the expression of miR‑135A1 in patient CRC tissues and adjacent non‑tumor tissues, as well as cell lines. The association between miR‑135A1 and clinical characteristics of patients with CRC was also investigated. RT‑qPCR and western blotting were used to evaluate the expression of miR‑135A1 targets. Regulation of cyclin G2 (CCNG2) by miR‑135A1was confirmed using luciferase assays. The biological effects of miR‑135A1 were assessed in transfected and untransfected CRC cell lines using colony formation assays, cell‑cycle analysis by flow cytometry, and CCK‑8 assays. miR‑135A1 was upregulated in CRC specimens and cell lines. miR‑135A1 expression was strongly associated with poor cell differentiation, high expression of carbohydrate antigen (CA)125, CA199, carcinoembryonic antigen and survival rate of patients with CRC. Expression of CCNG2 was downregulated in CRC patients and cell lines, and was further demonstrated to be among the downstream targets of miR‑135A1. The present study indicated that inhibition of miR‑135A1 expression leads to cell cycle arrest and inhibition of proliferation of CRC cells via increasing CCNG2 expression. In the present study, activation of FXR by GW4064 increased CCNG2 expression via suppression of miR‑135A1 expression, and the FXR/miR‑135A1/CCNG2 axis was demonstrated to be involved in mediating cell proliferation. In conclusion, activation of FXR by GW4064 suppresses cell proliferation and causes cell cycle arrest in CRC, and the miR‑135A1/CCNG2 pathway was suggested to be involved in this step.

Breast cancer is a type of heterogeneous disease, which manifests as different molecular subtypes due to the complex nature of tumour initiation, progression, and metastasis. Accurate identification of a breast cancer subtype plays crucial roles in breast cancer management. Herein, taking advantage of the efficient quenching properties of black phosphorus nanosheets (BPNSs), in combination with the high specificity of ssDNA (or RNA) aptamer, a fluorometric duplexed assay that is capable of the simultaneous detection of two tumour markers within one run is developed. When mixed with BPNSs, the fluorescence of both FAM and Cy3 labelled aptamers was quenched. The presence of different subtypes of breast cancer cells restored the FAM and Cy3 fluorescence in distinct patterns according to their intrinsic features. The proposed assay can precisely recognise label-free breast cancer subtypes, providing an efficient method for cell type identification and guidance for subsequent breast cancer treatment. The significance of the proposed study is two-fold. First, we provide a simple method for sensitive and specific tumour cell detection; secondly, and more importantly, the proposed dual assay allows precise recognition of tumour cells and thus opens a door for rapid characterization and sorting of a wide range of tumours without using expensive instruments.

Current studies tend to consider N-myc downstream regulated gene 1 (NDRG1) as a tumor suppressor gene, inhibiting cell proliferation and invasion. NDRG1 expression in cancer cells is generally low, but the molecular mechanism is unclear. Aberrant methylation of CpG islands (CGIs) in gene promoter was able to inactivate tumor suppressor genes and activate oncogenes, disordering cell proliferation and apoptosis, playing a promotion role in tumor occurrence and progression. The present study was performed to investigate the effect of epigenetic modification of NDRG1 on prostate cancer (PCa) cells. The protein expression in human specimens was measured by immunohistochemical staining. The expression level of NDRG1 was changed by plasmid vectors in PCa cells. These cells were used to study proliferation and invasiveness. NDRG1 expression in normal prostate cells was higher than that in PCa cells. Downregulation of NDRG1 expression enhanced cell proliferation and invasiveness. In contrast, its upregulation could reduce cell proliferation and invasiveness. In PCa cells, the methylation rate of CGIs in the promoter region of NDRG1 was higher than that in normal prostate cells. 5-Aza-CdR, a methylation inhibitor, was able to effectively reverse the aberrant methylation of NDRG1, enhancing its expression, inhibiting cell growth. NDRG1 can inhibit the cell proliferation and invasion of PCa, but its expression level is low. The aberrant methylation of NDRG1 promoter is an important mechanism for gene silencing, playing an important role in tumor occurrence and progression. Therefore, reversing the aberrant methylation of NDRG1 may be used for PCa treatment.

We report electrically-pumped MEMS-VCSELs with a record 70 nm continuous wavelength sweep at 1057-nm with 600 kHz rate using a novel air-cavity-dominant design. Such devices are promising for swept-source OCT and 3D sensing applications.

We report tunable VCSELs emitting around 1060 nm, enabled by high-contrast grating (HCG) mirror. Single-mode continuous-wave (CW) operation up to 110 °C is demonstrated, with room-temperature single-mode output power >1.3 mW at a very low threshold of ~300 µA. The obtained thermal resistance of 0.88 °C/mW is low for VCSELs with an oxide-confined laser aperture. A wide, continuous tuning range up to 40 nm was achieved with electrostatic and thermal tuning, at a fast tuning speed up to 1.15 MHz. In addition, we developed transverse-mode control designs of HCGs to greatly improve the single-mode yield of oxidized VCSELs. The cost-effective, wafer-scale fabrication makes these VCSELs promising as tunable light sources for swept-source optical coherent tomography (SS-OCT) and LiDAR applications.

The information about clinical presentation and outcome of elderly hepatocellular carcinoma (HCC) patients is limited. We performed this study to assess the impact of age on potential differences in clinical characteristics, treatment patterns and outcome in HCC patients. Clinical data of 164 “elderly” (≥70 years old) and 531 “younger” (

We present a MEMS-actuated, high-contrast grating VCSEL operating at 1060 nm with a 73 nm tuning range. The tuning range ratio (Δλ/λ) of 6.9% is the highest for an electrically pumped laser, to the best of our knowledge.

Silicon nitride spot-size converters were fabricated in a damascene process to improve the performance of supercontinuum generation in arsenic-free chalcogenide waveguides. Supercontinuum generation covering 950–1750 nm with 200 pJ pulses is demonstrated.

We report on wafer-scale processing of GeSbS-based chalcogenide waveguides on silicon substrates. High Q-factor (106), low propagation loss (0.2 dB/cm), and supercontinuum generation in a 2-cm-long waveguide with 120 pJ pulses are demonstrated.

This paper proposes a broadband three-device Doherty power amplifier design. A new load modulation network with a shunt quarter-wavelength (λ/4) short stub is introduced for bandwidth extension. Comprehensive analysis of the proposed configuration is given to illustrate the operational principle. For demonstration purpose, a twin-peaking single-carrier Doherty amplifier prototype is devised based on three identical 10W GaN HEMTs. Measurement results show that at least 40% drain efficiency is achieved at 8-dB back-off power, from 2.0 to 2.6 GHz.

In recent years, subwavelength dielectric gratings have been engineered for use as planar focusing elements at optical communication frequencies. Pioneering designs were based on aperiodic one-dimensional gratings, which were polarization-sensitive and designed bar by bar. In this paper, we present our recent designs which eliminated the polarization dependence by using a novel two-dimensional hexagonal lattice and algorithm to build the lens. In this way, lens can be designed algorithmically, with the inherent geometry requiring the use of only one period for the hexagonal lattice. We propose a unique geometry for designing two-dimensional grating lenses: dielectric posts arrayed in concentric circles. Because it is straightforward to space concentric rings apart at varying distances, we no longer need to restrict the design to a uniform grating period. By choosing two periodicities to work with, we managed to algorithmically design a two-dimensional lens, but with the advantage that our smallest feature sizes are up to twice as large as those of lenses designed with only one period. This increases the ease of fabrication for lenses working at current wavelengths and opens up the possibility for working with shorter wavelengths. Furthermore, this concentrically arrayed grating lens can be designed using phase information calculated for a periodic hexagonal lattice, even though the two designs show very little geometric resemblance. Also, we found that the grating lens is suitable not only for focusing plane waves, but also for imaging point sources. Finally, we show that bifocal lenses can be crated from diffraction gratings using our algorithm as well.

High efficiency phase holograms are designed and implemented using aperiodic two-dimensional (2D) high-contrast gratings (HCGs). With our design algorithm and an in-house developed rigorous coupled-wave analysis (RCWA) package for periodic 2D HCGs, the structural parameters are obtained to achieve a full 360-degree phase-tuning range of the reflected or transmitted wave, while maintaining the power efficiency above 90%. For given far-field patterns or 3D objects to reconstruct, we can generate the near-field phase distribution through an iterative process. The aperiodic HCG phase plates we design for holograms are pixelated, and the local geometric parameters for each pixel to achieve desired phase alternation are extracted from our periodic HCG designs. Our aperiodic HCG holograms are simulated using the 3D finite-difference time-domain method. The simulation results confirm that the desired far-field patterns are successfully produced under illumination at the designed wavelength. The HCG holograms are implemented on the quartz wafers, using amorphous silicon as the high-index material. We propose HCG designs at both visible and infrared wavelengths, and our simulation confirms the reconstruction of 3D objects. The high-contrast gratings allow us to realize low-cost, compact, flat, and integrable holograms with sub-micrometer thicknesses.

Optical properties of two-dimensional (2D) high-contrast gratings are investigated. We analyze the mechanisms for high-contrast gratings to function as various high-performance optical components. Our top-down design procedure allows us to efficiently obtain initial structural parameters and engineer them for a wide range of applications, such as reflectors, filters, resonators, waveplates, and even 2D phase plates. Simulation results of our designed structures show ultra-high power efficiency, and excellent agreement with our predicted functionalities.

In the recent decade, the research field using arrays of high-index-contrast near-wavelength dieletric structures on flat surfaces, known as high-contrast metastructures (HCMs) or metasurfaces, has emerged and expanded rapidly. Although the HCMs and metasurfaces share great similarities in physical structures with photonic crystals (PhCs), i.e. periodic nanostructures, many differences exist in their design, analysis, operation conditions, and applications. In this paper, we provide a generalized theoretical understanding of the two subjects and show their intrinsic connections. We further discuss the simulation and design approaches, categorized by their functionalities and applications. The similarity and differences between HCMs, metasurfaces and PhCs are also discussed. New findings are presented regarding the physical connection between the PhC band structures and the 1D and 2D HCM scattering spectra under transverse and longitudinal tilt incidence. Novel designs using HCMs as holograms, spatial light modulators, and surface plasmonic couplers are discussed. Recent advances on HCMs, metasurfaces and PhCs are reviewed and compared for applications such as broadband mirrors, waveguides, couplers, resonators, and reconfigurable optics., 58 pages, 44 figures, review article

We present a unique heterogeneous integration approach for VCSELs on silicon using eutectic bonding. An electrically pumped III-V – silicon heterogeneous VCSEL is demonstrated using a high-contrast grating (HCG) reflector on silicon. CW output power >1.5 mW, thermal resistance of 1.46 K/mW, and 5 Gb/s direct modulation is demonstrated. We also explore the possibility of an all-HCG VCSEL structure that would benefit from stronger thermal performance, larger tuning efficiency, and higher direct modulation speeds.

A design rule to obtain broadband high reflection and transmission in 2D high contrast gratings is proposed. Our design method is convenient for engineering the orbital angular momentum of light using 2D grating array.

Metal-cavity submonolayer (SML) quantum-dot (QD) microlasers are demonstrated at room temperature under continuous-wave electrical injection for 2-μm-radius devices and pulsed operation for 0.5-μm-radius devices. Compared to our previous quantum well devices, the superior optical properties of SML QDs provide the possibility for further size reduction. Size-dependent lasing characteristics are extracted from measurements to investigate the device physics for future size reduction. An optical cavity model using the transfer matrix and the effective index method including metal dispersion is developed and used for both the design and the experimental results analysis. The laser uses an active region consisting of three groups of SML QDs, and each group consists of 10 stacks of 0.5-monolayer InAs QD layers. The cylindrical microcavity is formed by hybrid metal-distributed Bragg reflectors (DBRs) mirrors with an optimized SiNx passivation layer on the sidewall to reduce the metal loss and to avoid the leakage current. The transverse optical modes are solved using the Maxwell equations, and the resonance condition is determined by roundtrip phase matching. Vertically-correlated QDs are modeled as quantum disks, and the wave functions and eigenenergies in both conduction and valance bands are solved from Schrodinger equation. Carrier-dependent material gain is calculated using Fermi’s golden rule and included in the model. The lasing wavelengths, quality factors, and confinement factors for cavity modes are the inputs for the rate-equation model, which predicts the light output power vs. current behavior and has shown excellent agreement with experiments. Size-dependent physical quantities such as leakage current and spontaneous emission coupling factor are extracted and investigated. Further size reduction using only four pairs of DBRs is proposed.

We present low-threshold dielectric-cavity surface-emitting microlasers working at room temperature under continuous-wave electrical injection with device diameter down to 2 mm. Size-dependent lasing properties are predicted theoretically and demonstrated experimentally.

We report our recent experimental and theoretical development on metal-cavity surface-emitting quantum-dot microlasers. Room-temperature operation is achieved for devices with diameters close to one wavelength. The experimental data agrees well with our developed theoretical model.