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1.
J Opt Soc Am A Opt Image Sci Vis ; 41(3): 406-413, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38437428

ABSTRACT

We present a dish spliced concentrator (DSC) featuring hexagonal spherical sub-mirrors of uniform size. The DSC offers advantages over traditional parabolic dish concentrators, including a compact layout, cost-effectiveness, higher concentration ratio, and improved light uniformity. Its versatility allows for both uniform and focused light concentration by adjusting parameters like the focal length of the DSC, making it suitable for concentrating photovoltaic (CPV) and concentrating solar thermal (CST) applications. We design the DSC using three-dimensional (3D) vector rotation theory, implementing ray tracing and transmission characteristic analysis based on three-dimensional vector reflection theory. We establish a simulation model to evaluate the impact of geometric parameters on the DSC's optical performance.

2.
Appl Opt ; 63(1): 239-248, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38175026

ABSTRACT

Elliptical Gaussian beams generated by laser diodes (LDs) often exhibit asymmetrical divergence angle distribution, which limits their practical applications. In this study, we propose what we believe is a novel approach to shape and collimate the elliptical output beam from a LD. The design process involves the construction of two freeform reflective surfaces on a reference circle using a three-dimensional point-by-point iterative method, based on the law of conservation of energy, the vector reflection theory, and Fermat's principle. The output beam's maximum divergence angle is effectively compressed to 3.1579 mrad. The design is compact with a folded optical path and antenna size of 368.8c m 3. This paper presents a comprehensive design and optimization process, along with an in-depth analysis of the system's performance, thereby offering novel insights for emerging optical design practitioners.

3.
J Opt Soc Am A Opt Image Sci Vis ; 40(11): 1986-1993, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-38038063

ABSTRACT

We predict the reversal of the phase chirality before and after the focal plane during propagation based on ray tracing. The interference patterns of a focused vortex beam (FVB) and a plane beam during propagation verify the fact of phase chirality reversal through diffraction theoretical simulations and experiments. Also, we deduce an analytical expression for the caustic based on the ray equation, which effectively represents the change of the hollow light field during propagation. Simulation and experimental results demonstrate the effectiveness of the caustic in describing the variation of the global hollow dark spot radius. Furthermore, based on the caustic results at the focal plane, we customize FVBs with the same dark spot radii but different topological charges. Our research results reveal the characteristics of the light field and phase distribution of the FVB during propagation, which will expand our understanding of the properties of the FVB and provide a reference value for applications such as chiral particle manipulation and topological charge recognition.

4.
Drug Des Devel Ther ; 16: 3589-3598, 2022.
Article in English | MEDLINE | ID: mdl-36248244

ABSTRACT

Background: Hypoxia is a frequent feature of solid tumors which significantly affects the efficacy of treatments such as chemotherapy. In addition, exosomes from hypoxic cancer cells could contribute to the chemoresistance of tumor cells through carrying miRNAs. It has been shown that miR-106-5p level was upregulated in glioma. However, whether exosomes derived from hypoxic glioma cells could affect temozolomide (TMZ) resistance in glioma through carrying miR-106a-5p remains unexplored. Methods: Exosomes were isolated from glioma cells under normoxia or hypoxia condition. EdU staining and flow cytometry assays were used to assess the cell proliferation and cell apoptosis. The relation between miR-106a-5p and PTEN was investigated by dual luciferase assay. Results: MiR-106a-5p was enriched in exosomes derived from hypoxic glioma cells compared to exosomes from cells under normoxia condition. Additionally, hypoxic glioma cells were able to transfer exosomes to glioma cells, resulting in a significant increase of miR-106a-5p level in cells. TMZ remarkably suppressed glioma cell proliferation and triggered cell apoptosis. However, hypoxic glioma cell-derived exosomes markedly promoted the proliferation and suppressed the apoptosis in TMZ-treated glioma cells, and miR-106a-5p inhibitor was able to abolish these phenomena. Meanwhile, PTEN was verified to be a direct target of miR-106a-5p. Furthermore, TMZ elevated PTEN and Bax level and reduced p-Akt level in glioma cells, whereas these changes were reversed by hypoxia glioma cell-derived exosomes. Furthermore, hypoxia glioma cell-derived exosomes reduced the sensitivity of glioma cells to TMZ in vivo via downregulating PTEN. Conclusion: Collectively, exosomal miR-106a-5p derived from hypoxia glioma cells could reduce the sensitivity of glioma cells to TMZ through downregulating PTEN. Thus, our study might provide new strategies for improving the clinical efficacy of TMZ on glioma.


Subject(s)
Exosomes , Glioma , MicroRNAs , Apoptosis , Cell Line, Tumor , Cell Proliferation , Drug Resistance, Neoplasm , Glioma/drug therapy , Glioma/pathology , Humans , Hypoxia , MicroRNAs/genetics , MicroRNAs/therapeutic use , Proto-Oncogene Proteins c-akt , Temozolomide/pharmacology , bcl-2-Associated X Protein
5.
Nano Lett ; 21(15): 6480-6486, 2021 Aug 11.
Article in English | MEDLINE | ID: mdl-34324350

ABSTRACT

Lower coercivity (HC) and magnetic anisotropy (K1) coupled with high mechanical strength are essential properties for Co-based soft magnetic thin films; however, the strength-coercivity trade-off limits their development. Co with face centered cubic structure (fcc) exhibits lower HC and K1 than its grand hexagonal close packed structure (hcp); however, metastable fcc-phase Co is hard to stabilize. Here, by using Cu (100) seed layer, we synthesized micron-thick fcc Co films with self-formed three-dimensional nanoscale stacking faults (3D-nSFs) that could achieve high strengths without sacrificing soft magnetic properties. The 3D-nSFs, induced by the Co/Cu interface, could not only stabilize the metastable fcc Co to yield lower HC but also impede dislocation motion to strengthen Co films. More importantly, we successfully tailored the density of 3D-nSFs and confirmed a large variation in magnetic coercivity (by 100%) and indentation hardness (by 25%). This work provides a new strategy for integrated performance optimization by interface design and strain engineering.

6.
PLoS One ; 7(8): e40178, 2012.
Article in English | MEDLINE | ID: mdl-22916093

ABSTRACT

BACKGROUND: Lung cancer is a heterogeneous disease with multiple signaling pathways influencing tumor cell survival and proliferation, and it is likely that blocking only one of these pathways allows others to act as salvage or escape mechanisms for cancer cells. Whether combined inhibition therapy has greater anti-tumor activity than single inhibition therapy is a matter of debate. Hence, a meta-analysis comparing therapy inhibiting both VEGFR and EGFR signaling pathways with that inhibiting EGFR signaling pathway alone was performed. METHODOLOGY AND PRINCIPAL FINDINGS: We searched PubMed, EMBASE database and the proceedings of major conferences for relevant clinical trials. Outcomes analyzed were objective tumor response rate (ORR), progression-free survival (PFS), overall survival (OS) and toxicity. Besides, subgroup analyses were performed to investigate whether the combined inhibition therapy is best performed using combination of selective agents or a single agent with multiple targets. Six trials recruiting 3,302 patients were included in the analysis. Combined inhibition therapy was associated with a 3% improvement in OS as compared with single-targeted therapy, but this difference was not statistically significant (HR, 0.97; 95% CI, 0.89-1.05; P=0.472). Patients receiving combined inhibition therapy had significant longer PFS than the group with single-targeted therapy (HR, 0.80; 95% CI, 0.67-0.95; P=0.011). There was no difference in the ORR between the groups (OR, 1.44; 95% CI, 0.95-2.18; P=0.085). Subgroup analysis revealed that combined inhibition therapy using combination regimens was associated with statistically significant improvement in both ORR and PFS. Toxicity was greater in combined inhibition therapy. CONCLUSIONS: There is no evidence to support the use of combined inhibition therapy in unselected patients with advanced NSCLC. However, given the significant advantage in ORR and PFS, combined inhibition therapy using combination regimens may be considered for further evaluation in subsets of patients who may benefit from this treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung/therapy , ErbB Receptors/metabolism , Lung Neoplasms/therapy , Receptors, Vascular Endothelial Growth Factor/metabolism , Signal Transduction , Carcinoma, Non-Small-Cell Lung/metabolism , ErbB Receptors/antagonists & inhibitors , Humans , Lung Neoplasms/metabolism , Receptors, Vascular Endothelial Growth Factor/antagonists & inhibitors , Survival Analysis
7.
Asian Pac J Cancer Prev ; 12(11): 2857-63, 2011.
Article in English | MEDLINE | ID: mdl-22393954

ABSTRACT

BACKGROUND: Vandetanib, an oral inhibitor of vascular endothelial growth factor receptor and epidermal growth factor receptor signaling, has attracted wide interest in treatment of advanced non-small-cell lung cancer (NSCLC). We aimed to assess its efficacy and safety via a systematic review and meta-analysis. METHODS: Trials comparing vandetanib-based therapy and non-vandetanib therapy for advanced NSCLC were identified. Endpoints evaluated were progression-free survival (PFS), overall survival (OS), objective tumor response rate (ORR), and toxicity. RESULTS: Seven trials including 4,492 patients were included in the analysis. As compared with placebo, vandetanib yielded a clear benefit for ORR (odds ratio (OR) = 2.04; 95% CI, 1.60-2.61; P <0.001), and a clinically and statistically significant 25% improvement in PFS (hazard ratio (HR) = 0.75; 95% CI, 0.66- 0.85; P < 0.001). However, these benefits did not translate into a significant improvement in OS (HR = 0.95; 95% CI, 0.88-1.04; P = 0.291). Subgroup analyses showed that vandetanib 100mg/d was associated with greater antitumor activity than 300 mg/d when given in combination with chemotherapy. In addition, the pooled results demonstrated no statistically significant difference between vandetanib and single-targeted agents in PFS, ORR or OS. Vandetanib was associated with more frequent adverse events. CONCLUSIONS: Vandetanib, as compared with placebo, significantly increases ORR and PFS, but does not improve OS in the treatment of advanced NSCLC. As compared with single-targeted agent, vandetanib does not provide any efficacy advantage. Furthermore grade 3 or greater toxicity proved greater in the vandetanib arm.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/mortality , Lung Neoplasms/drug therapy , Piperidines/therapeutic use , Quinazolines/therapeutic use , Antineoplastic Agents/adverse effects , Carcinoma, Non-Small-Cell Lung/pathology , Disease-Free Survival , ErbB Receptors/antagonists & inhibitors , Female , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Piperidines/adverse effects , Quinazolines/adverse effects , Receptors, Vascular Endothelial Growth Factor/antagonists & inhibitors
8.
Yi Chuan ; 27(2): 201-4, 2005 Mar.
Article in Chinese | MEDLINE | ID: mdl-15843345

ABSTRACT

By examining the lymphocytic chromosomes of peripheral blood from patients with amenorrhea, spontaneous abortion and stillbirth history, .the 16 rare species of human chromosomal abnormal karyotypes were discovered. They were 46,XY,t(6;11)(q25;p15);46,XY,inv(3)(p25;q29);46,XY,t(7;18)(q10;p10);46,X,t(X;13)(q24;q14);46,XY,t(4;7)(q33;q22);46,XY,t(8;15)(q24;q15);46,XY,t(2;17)(q33;q25);46,XX,t(4;7)(q34;q11);46,XX,t(1;3)(p36;p23);46,XX,t(4;6)(q35;p11);46,X,inv(X)(q22;q28);46,XX,t(7;10)(p11;q26);46,XX,t(3;6)(p21;q23);46,XX,t(8;16)(p21;p13);46,XX,t(8;9)(q21;q34);46,XY,t(17;22)(q21;q11). Their clinical situation were described. Discussion on the relationship between the chromosomal aberrations and phenotype effect indicates the importance of chromosome karyotyping in patients with abnormal reproductive history.


Subject(s)
Chromosome Aberrations , Chromosome Disorders/genetics , Abortion, Habitual , Adolescent , Adult , Amenorrhea , Chromosome Disorders/pathology , Chromosome Inversion , Female , Humans , Karyotyping , Male , Pregnancy , Stillbirth , Translocation, Genetic
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 21(1): 83-5, 2004 Feb.
Article in Chinese | MEDLINE | ID: mdl-14767919

ABSTRACT

OBJECTIVE: To investigate the normal range of (CAG)n in spinocerebellar ataxia type 1 (SCA1) gene and spinocerebellar ataxia type 3 (SCA3/MJD) gene in 110 normal subjects of Han population in Northeastern China, to assess the genotypes for clinically diagnosed spinocerebellar ataxia(SCA) individuals including 25 patients from 8 families and 6 sporadic patients, and to make presymptomatic and prenatal diagnosis. METHODS: DNA fragments from the normal subjects and the patients were detected by fluorescence-PCR. Homozygosities were selected for DNA sequencing. RESULTS: The normal ranges of (CAG)n of SCA1 and SCA3/MJD were 20-39 and 14-38 repeats respectively, SCA1 was found mostly to be 26 and 27 repeats, allele frequency 34.09% and 20.91%; heterozygosity was 84.55%, SCA3/MJD was found mostly to be 14 repeats, allele frequency 39.55%, heterozygosity was 78.18%.(CAG)(68) of SCA3/MJD gene of one affected individual had been found in a family but no CAG mutative expansion in related members was observed. CONCLUSION: The normal ranges of CAG repeats vary with areas and races. SCAs genotyping is the first choice in presymptomatic and prenatal diagnosis.


Subject(s)
Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Trinucleotide Repeats/genetics , Ataxin-1 , Ataxin-3 , Ataxins , China , DNA/chemistry , DNA/genetics , Family Health , Female , Gene Frequency , Genotype , Humans , Machado-Joseph Disease/diagnosis , Machado-Joseph Disease/genetics , Male , Pedigree , Repressor Proteins , Sequence Analysis, DNA , Spinocerebellar Ataxias/diagnosis , Spinocerebellar Ataxias/genetics , Trinucleotide Repeat Expansion/genetics
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