Characterization of pyroptosis-related genes in esophageal cancer and construction of a prognostic model.

OBJECTIVE: Esophageal cancer (EC) is a highly malignant digestive system tumor that often lacks evident early symptoms and has a poor prognosis. Pyroptosis, a form of programmed cell death, has been shown to be associated with the occurrence and progression of many malignancies. However, its role in esophageal cancer remains unclear. This work aimed to evaluate the prognostic value of pyroptosis-related genes (PRGs) in EC using data from The Cancer Genome Atlas (TCGA) cohort. MATERIALS AND METHODS: The RNA-seq data from 171 esophageal samples in the TCGA database were employed. Differential expression genes (DEGs) between tumor and non-tumor samples were compared. Protein-protein interaction (PPI) networks were constructed using the STRING database, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and Gene Ontology (GO) analyses were performed using the "clusterProfiler" package in R. Furthermore, based on the DEGs, all esophageal cancer cases were classified into three subtypes. A risk model for gene features was established using the LASSO regression method, and EC patients in the TCGA cohort were divided into high-risk and low-risk groups. RESULTS: A total of 614 PRGs were identified. Among them, 32 DEGs (31 upregulated and 1 downregulated) were found between normal esophageal tissue and EC tissue. PPI analysis identified key genes including IL-1ß, CASP1, AIM2, HMGB1, GSDMD, PYCARD, IL-18, BAK1, and TP53. On the other hand, the low-risk group exhibited a significantly higher survival rate than the high-risk group (p < 0.001). Combined with the clinical characteristics of the TCGA cohort, it was found that the risk score was an independent prognostic factor for overall survival (OS) prediction in EC patients. KEGG and GO analyses revealed the enrichment of genes associated with cell proliferation in the high-risk group. CONCLUSIONS: PRGs play a crucial role in the occurrence and development of EC and can be used to predict the prognosis of EC patients.

[The characteristics and risk factors of cardiovascular diseases and psychological status in science and technologyists].

Objectives: To investigate the prevalence and related factors of cardiovascular diseases (CVD) and psychological problems in Chinese science and technology workers. Methods: The investigation was organized and conducted by the Innovative and Development Institute of China Association of Senior Scientists and Technologists and Capital Medical University Affiliated Beijing Anzhen Hospital, and included science and technology workers from research institutions and medical institutions in China by random sampling methods through face-to-face and online questionnaire investigation from July 1, 2019 to March 31, 2021. Information including age, sex, work stress status, CVD history, sleep, depression, and anxiety were included in the questionnaire. Results: This survey included 14 552 subjects. Among them, 25.5% were suffered from CVD, 48.6% were with insomnia, 28.8% experienced depression/anxiety (including only depression, only anxiety, depression combined with anxiety), and 15.6% had CVD in combined with depression/anxiety. Taking those without CVD and depression/anxiety as reference group, multiple logistic regression analyses showed that work stress increased the risk of depression/anxiety in subjects without CVD (manageable work stress, OR=2.253, 95%CI 1.583-3.206, overwhelming work stress OR=7.899, 95%CI 5.094-12.250), and drinking increased the risk of CVD (OR=1.978, 95%CI 1.382-2.833). Moreover, overwhelming work stress (OR=4.012, 95%CI 2.515-6.399) and smoking (OR=2.342, 95%CI 1.603-3.421) increased the risk of depression/anxiety in subjects with CVD (all P<0.001). Conclusion: The high morbidities of depression/anxiety, CVD, and CVD in combination with depression/anxiety urge us to take actions to protect the heart and mental health of scientific and technological workers.

Optical coupling and splitting with two parallel waveguide tapers.

A coupling and splitting device comprising a width taper and a spatial-modulated subwavelength grating waveguide (SSGW) is proposed. The width taper is a waveguide with increasing width and the SSGW is a waveguide grating whose width and thickness are constant but the filling factor increases along the light propagation. Thus, the effective index of the subwavelength grating increases according to the effective medium theory. Light of orthogonal polarizations from a single-mode fiber can be coupled efficiently with the two parallel tapers. Furthermore, the coupled lights of orthogonal polarizations in the two tapers can be further split with connecting bent waveguides. Fabrication of the device is fully compatible with current complementary metal oxide semiconductor technology.

Ultra-high order ring resonator system with sharp transmission peaks.

We propose a relay ring resonator structure which comprises multiple cascaded microring resonators, in which the drop waveguide of a microring resonator is also the input waveguide of the subsequent microring resonator, and so forth. Thus, the transmission response of the relay ring resonator structure has sharp peaks, high out-of-band rejection ratios, and long group delays. A relay ring resonator structure comprising 90 microrings is fabricated on silicon nitride wire waveguides. The simulation and experimental results are in good agreement.

Improving coupling efficiency of fiber-waveguide coupling with a double-tip coupler.

A double-tip coupler that comprises two inversely and laterally tapered waveguides is experimentally demonstrated for efficient light coupling between a fiber and a sub-micron silicon nitride waveguide. The coupling efficiency of the fabricated double-tip coupler can be improved by as much as over 2 dB per coupling facet, compared with that of a single-tip one with the same tip width of 180 nm. The effect of the gap width of the double tips on the coupling efficiency is studied both in experiment and simulation.

Low propagation loss SiN optical waveguide prepared by optimal low-hydrogen module.

We investigated low-hydrogen SiN films prepared by a low temperature (350 degrees C) PECVD method. The impact of SiH(4)/N(2) flow ratio and radio frequency power on the hydrogen content in the SiN films was studied. In this work, we demonstrated a low-loss sub-micron SiN waveguide by using the corresponding optimal SiN films. The propagation loss was found to be as low as -2.1+/-0.2 dB/cm at 1550 nm with waveguide cross-section of 700 nm x 400 nm. The results suggest that the SiN films grown by PECVD with low hydrogen can be used in photonics integrated circuits for new generation communications applications.

Cascade wide-angle Y-junction 1 x 16 optical power splitter based on silicon wire waveguides on silicon-on-insulator.

A 1 x 16 optical power splitter with wide splitting angle, uniform outputs, and low excess loss is demonstrated. The 1 x 16 splitter comprising cascaded 1 x 2 splitters with arc-shaped branching waveguides is fabricated on the silicon-on-insulator (SOI) substrate. The gap between the branching waveguides is widened in a short propagation length such that influences of etch residues and air voids in the gap on the optical power uniformity are reduced significantly. The measured power uniformity of the 1 x 16 splitter is better than 0.3 dB at wavelength of 1550 nm.

Effective thermo-optical enhanced cross-ring resonator MZI interleavers on SOI.

A cross-ring (CR-) Mach-Zehnder interferometer (MZI) interleaver structure has been proposed and fabricated. It uses an '8' shaped cross-ring resonator to replace the conventional circular ring resonator. Thus, the new structure can have the function of add-signal. Furthermore, a thermo-optical fine tuning has been applied, which improves the crosstalk performance from approximately -10 dB to approximately -20 dB with 9 V applied on the heater of the 3-dB directional coupler.

Fast and low power Michelson interferometer thermo-optical switch on SOI.

We designed and fabricated silicon-on-insulator based Michelson interferometer (MI) thermo-optical switches with deep etched trenches for heat-isolation. Switch power was reduced approximately 20% for the switch with deep etched trenches, and the MI saved approximately 50% power than that of the Mach-Zehnder interferometer. 10.6 mW switch power, approximately 42 micros switch time for the MI with deep trenches, 13.14 mW switch power and approximately 34 micros switch time for the MI without deep trenches were achieved.

Low loss (approximately 6.45dB/cm) sub-micron polycrystalline silicon waveguide integrated with efficient SiON waveguide coupler.

In this communication, the sub-micron size polycrystalline silicon (poly- Si) single mode waveguides are fabricated and integrated with SiON waveguide coupler by deep UV lithography. The propagation loss of poly-Si waveguide and coupling loss with optical flat polarization-maintaining fiber (PMF) are measured. For whole C-band (i.e., lambda approximately 1520-1565nm), the propagation loss of TE mode is measured to approximately 6.45+/-0.3dB/cm. The coupling loss with optical flat PMF is approximately 3.4dB/facet for TE mode. To the best of our knowledge, the propagation loss is among the best reported results. This communication discusses the factors reducing the propagation loss, especially the effect of the refractive index contrast. Compared to the SiO(2) cladding, poly-Si waveguide with SiON cladding exhibits lower propagation loss.

Proposed silicon wire interleaver structure.

A Ring-resonator Mach-Zehnder interferometer (RR-MZI) optical interleaver structure comprising a ring resonator (RR) and a 3 dB directional coupler is proposed. The interleaver is fabricated with 300 nm x 300 nm silicon wires on silicon-on-insulator (SOI) wafers. The fabricated interleaver demonstrates a flat-top spectral response, and the measured free spectral range (FSR) is approximately 20 nm. The insertion loss (IL) of the device is approximately -10 dB and the polarization dependent loss (PDL) <5 dB. Both the experimental and simulation results are in good agreement.

Passive ring-assisted Mach-Zehnder interleaver on silicon-on-insulator.

A passive ring-assisted Mach-Zehnder interferometer optical interleaver comprising a Y-bench, a 3-dB directional coupler, a ring-resonator, and a delay line is proposed. The interleaver is fabricated with 300 nm x 300 nm silicon wires on silicon-on-insulator. The fabricated interleaver demonstrates a flat-top spectral response. The measured free-spectral range is approximately 4 nm, the insertion loss is approximately -8 dB, and the crosstalk is <- 10 dB. Both the experimental and simulation results are in good agreement.

Evolution of the isochore structure in the scale of chromosome: insight from the mutation bias and fixation bias.

Following the development of reliable methods for inferring the direction of mutations of the single nucleotide polymorphism (SNP), and the revealing of the human isochore map, it has become possible to investigate the evolution of the isochore structure in a continuous region. In this study, the recent evolution of the isochore structure on human chromosome 18, as inferred from the SNP, was examined. A remarkable mutation bias was found, which was destroying the present isochore structure. However, a fixation bias contributed by the biased gene conversion (BGC) effect and a rising fixation probability of derived alleles with increasing GC content was extending the present isochore structure. Combining the two opposing processes, the old isochore structure was declining and a more homogenous isochore structure with higher GC content was being formed on the chromosome. During this process, both the CpG and genic sites, which were present in the isochore but were paid little attention to before, played an important role. In addition, the recombination was confirmed to promote the GC alleles fixed in the genome because of the BGC effect. For the first time, it was observed that with the occurrence of little recombination, AT alleles had the identical fixation probability with GC alleles in the recombination cold spots.

Multiplexing free-space optical signals using superimposed collinear orbital angular momentum states.

As a proof of concept, we experimentally demonstrate multiplexing of free-space optical signals in multiple channels labeled with different states of orbital angular momentum. The multiplexing process is carried out by a dynamic liquid-crystal spatial light modulator, while the phase function is calculated by an iterative algorithm. A binary amplitude computer-generated hologram serves as a demultiplexer.

A new method for RAPD primers selection based on primer bias in nucleotide sequence data.

Sequence analysis has proved that decamer nucleotides, used as primers of RAPD (random amplified polymorphic DNA), differ with each other greatly in number of annealing sites in the Arabidopsis thaliana genome. It is called the 'primer bias' by the authors. The biased primers produce a highly variable number of amplicons by polymerase chain reaction (PCR). The number of amplicons is proved to correlate with the number of annealing sites. Therefore, a statistical method is proposed for selecting efficient primers based on the primer bias in the genomic sequence. The method was tested by experiment in A. thaliana genome, and the results demonstrate that the method outperforms routine methods and can substantially increase the efficiency of RAPD methodologies. We also proved that the expressed sequence tags (ESTs) show a highly coincident bias pattern with that of the whole genomic sequence, and can therefore be used to assess efficiencies of primers for species whose genomic sequence data are currently unknown.

Variable-radius focused optical vortex with suppressed sidelobes.

We propose a design for a phase mask for generating an optical vortex with suppressed sidelobes in the focal plane where the radius of the intensity ring is variable. A radial modulation added to conventional phase mask exp(iltheta) projects the light diffracted from different annular zones into a single intensity ring in the focal plane.

Design and fabrication of a double-axicon for generation of tailorable self-imaged three-dimensional intensity voids.

We propose a new design for fabrication of a highly power-efficient double axicon to generate self-imaged three-dimensional intensity voids along the propagation of a beam. The conventional conical structure of an axicon is modified and shaped like an axiconlike structure with a double-gradient surface profile. The gradient conical surfaces generate Bessel beams with varying radial wave vectors that are superimposed and interfere to generate a sequence of three-dimensional intensity voids. The proposed element was fabricated using electron-beam lithography, and experimental verification of the design is reported.

Residue orbital angular momentum in interferenced double vortex beams with unequal topological charges.

When two vortex beams with unequal topological charges superpose coherently, orbital angular momentum (OAM) in the two beams would not be cancelled out completely in the interference. The residual OAMs contained by the superposed beam are located at different concentric rings and may have opposite orientations owing to the difference of the charges. The residual OAM can be confirmed by the rotation of microparticles when difference between the charges of two interfering beams is large.