A Wavelet Transform Method to Detect P and S-Phases in Three Component Seismic Data

The discrete time wavelet transform has been used to develop software that detects seismic P and S-phases. The detection algorithm is based on the enhanced amplitude and polarization information provided by the wavelet transform coefficients of the raw seismic data. The algorithm detects phases, determines arrival times and indicates the seismic event direction from three component seismic data that represents the ground displacement in three orthogonal directions. The essential concept is that strong features of the seismic signal are present in the wavelet coefficients across several scales of time and direction. The P-phase is detected by generating a function using polarization information while S-phase is detected by generating a function based on the transverse to radial amplitude ratio. These functions are shown to be very effective metrics in detecting P and S-phases and for determining their arrival times for low signal-to-noise arrivals. Results are compared with arrival times obtained by a human analyst as well as with a standard STA/LTA algorithm from local and regional earthquakes and found to be consistent.

Thioridazine reverses trastuzumab resistance in gastric cancer by inhibiting S-phase kinase associated protein 2-mediated aerobic glycolysis

BACKGROUND Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2(HER-2)-positive gastric cancer(GC).However,the efficacy of this treatment is hindered by substantial challenges associated with both primary and acquired drug resistance.While S-phase kinase associated protein 2(Skp2)overexpression has been implicated in the malignant progression of GC,its role in regulating trastuzumab resistance in this context remains uncertain.Despite the numerous studies investigating Skp2 inhibitors among small molecule compounds and natural products,there has been a lack of successful commercialization of drugs specifically targeting Skp2.AIM To discover a Skp2 blocker among currently available medications and develop a therapeutic strategy for HER2-positive GC patients who have experienced progression following trastuzumab-based treatment.METHODS Skp2 exogenous overexpression plasmids and small interfering RNA vectors were utilized to investigate the correlation between Skp2 expression and trastuzumab resistance in GC cells.Q-PCR,western blot,and immunohistochemical analyses were conducted to evaluate the regulatory effect of thioridazine on Skp2 expression.A cell counting kit-8 assay,flow cytometry,a amplex red glucose/glucose oxidase assay kit,and a lactate assay kit were utilized to measure the proliferation,apoptosis,and glycolytic activity of GC cells in vitro.A xenograft model established with human GC in nude mice was used to assess thioridazine's effectiveness in vivo.RESULTS The expression of Skp2 exhibited a negative correlation with the sensitivity of HER2-positive GC cells to trastuzumab.Thioridazine demonstrated the ability to directly bind to Skp2,resulting in a reduction in Skp2 expression at both the transcriptional and translational levels.Moreover,thioridazine effectively inhibited cell proliferation,exhibited antiapoptotic properties,and decreased the glucose uptake rate and lactate production by suppressing Skp2/protein kinase B/mammalian target of rapamycin/glucose transporter type 1 signaling pathways.The combination of thioridazine with either trastuzumab or lapatinib exhibited a more pronounced anticancer effect in vivo,surpassing the efficacy of either monotherapy.CONCLUSION Thioridazine demonstrates promising outcomes in preclinical GC models and offers a novel therapeutic approach for addressing trastuzumab resistance,particularly when used in conjunction with lapatinib.This compound has potential benefits for patients with Skp2-proficient tumors.

5-Bromo-2'-deoxyuridine labeling:historical perspectives,factors infiuencing the detection,toxicity,and its implications in the neurogenesis

The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DNA synthesis.Since the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating DNA.BrdU labeling is widely used for identifying neuron precursors and following their fate during the embryonic,perinatal,and adult neurogenesis in a variety of vertebrate species including birds,reptiles,and mammals.Due to BrdU toxicity,its incorporation into replicating DNA presents adverse consequences on the generation,survival,and settled patterns of cells.This may lead to false results and misinterpretation in the identification of proliferative neuroblasts.In this review,I will indicate the detrimental effects of this nucleoside during the development of the central nervous system,as well as the reliability of BrdU labeling to detect proliferating neuroblasts.Moreover,it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal,perinatal,and adult neurogenesis.Human adult neurogenesis will also be discussed.It is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.

The Phenomenon of High Hardness Values on the S-Phase Layer of Austenitic Stainless Steel via Screen Plasma Nitriding Process

The purpose of this study is to improve the surface properties of austenitic stainless steel using the double-folded electrode screen plasma nitriding (SPN) process. In general, the S-phase is well-known for its excellent properties such as improved hardness and wear resistance along with sustained corrosion resistance. The concentrated nitrogen via SPN process was injected to form S-phase with time at 713 K. This study was carried out under the conditions of 44 at% of nitrogen injection, which was higher than 25 at% known as the condition of no precipitation of S-phase formed by the SPN process, and 20 K higher than the maximum temperature without precipitation phase. The hardness analysis of stainless steel sample treated by the SPN process at 713 K showed a much higher value than the typical nitriding hardness at a depth of lower nitrogen than the maximum nitrogen concentration. The SPN 20 hr treated specimen showed the average value of 2339 HV while 40 hr showed the average value of 2215 HV. The result is attributed to the concentrated nitrogen formed in the SPN process reacting with the alloying elements contained in the base material to form fine precipitates, thus producing a synergy effect of the extreme hardening effect;that is, the movement of precipitates and dislocations due to the GP-zone (Guinier-Preston zone).

Skp2-RNAi suppresses proliferation and migration of gallbladder carcinoma cells by enhancing p27 expression

AIM:To explore the role of S-phase kinase-associated protein-2(Skp2)in gallbladder carcinoma and to identify whether depletion of Skp2 by Skp2-RNAi could attenuate proliferation and migration of gallbladder carcinoma.METHODS:Skp2-RNAi was transduced into cells of the gallbladder carcinoma cell line GBC-SD,using a lentiviral vector.The effect of Skp2-RNAi on the proliferation,migration,invasion and cell cycle of GBC-SD cells was studied using in vitro assays for cell proliferation,colony formation,wound healing and cell cycle.The expression of Skp2 and p27 was detected by real-time polymerase chain reaction and Western immunoblotting.The effect of Skp2-RNAi on the proliferation of GBC-SD cells in vivo was investigated by tumorigenicity experiments in nude mice.RESULTS:Lentivirus-mediated RNAi reduced the expression of Skp2 in cultured cells.The expression of the p27 protein increased along with the down-regulation of Skp2,although no significant difference was found in p27 mRNA expression.Flow cytometry revealed that Skp2-RNAi transfection significantly increased the proportion of cells in the S phase and significantly decreased the proportion of cells in the G 2 /M phase.No significant difference in the frequency of cells in the G0/G1 phase was observed.The results from the cell proliferation,colony formation and wound healing assays revealed that Skp2-RNAi transfection markedly inhibited the proliferation and migration of GBC-SD cells in vitro.Additionally,tumorigenicity experiments showed that suppression of Skp2 significantly decreased the weights of the tumors(0.56 ± 0.11 and 0.55 ± 0.07 g in the control and Scr-RNAi groups vs 0.37 ± 0.09 and 0.35 ± 0.08 g in the Skp2-RNAi-L and Skp2-RNAi-H groups).CONCLUSION:The expression of Skp2 in GBC-SD cells was inhibited following Skp2-RNAi transfection.Silencing of the Skp2 gene inhibited proliferation,migration and invasiveness of GBC-SD cells by mechanisms dependent on enhanced expression of the p27 protein.

Epidermal growth factor upregulates Skp2/Cks1 and p27^(kip1) in human extrahepatic cholangiocarcinoma cells

AIM:To evaluate the expression status of S-phase kinase-associated protein 2(Skp2)/cyclin-dependent kinases regulatory subunit 1(Cks1)and p27kip1,and assess the prognostic significance of Skp2/Cks1 expression with p27kip1in patients with extrahepatic cholangiocarcinoma.METHODS:Seventy-six patients who underwent curative resection for histologically confirmed extrahepatic cholangiocarcinoma at our institution from December1994 to March 2008 were enrolled.Immunohistochemical staining for Skp2,Cks1,p27kip1,and Ki67,along with other relevant molecular biologic experiments,were performed.RESULTS:By Cox regression analyses,advanced age(>65 years),advanced AJCC tumor stage,poorly differentiated histology,and higher immunostaining intensity of Skp2 were identified as independent prognostic factors in patients with extrahepatic cholangiocarcinoma.Exogenous epidermal growth factor(EGF,especially 0.1-10 ng/mL)significantly increased the proliferation indices by MTT assay and the mRNA levels of Skp2/Cks1 and p27kip1in SNU-1196,SNU-1079,and SNU-245 cells.The protein levels of Skp2/Cks1(from nuclear lysates)and p27kip1(from cytosolic lysate)were also significantly increased in these cells.There were significant reductions in the protein levels of Skp2/Cks1and p27kip1(from nuclear lysate)after the treatment of LY294002.By chromatin immunoprecipitation assay,we found that E2F1 transcription factor directly binds to the promoter site of Skp2.CONCLUSION:Higher immunostaining intensity of Skp2/Cks1 was an independent prognostic factor for patients with extrahepatic cholangiocarcinoma.EGF upregulates the mRNA and protein levels of Skp2/Cks1and p27kip1via the PI3K/Akt pathway and direct binding of E2F1 transcription factor with the Skp2 promoter.

Comprehensive analysis of pulsed plasma nitriding preconditions on the fatigue behavior of AISI 304 austenitic stainless steel

This study aims to draw an exact boundary for microstructural and mechanical behaviors in terms of pulsed plasma nitriding conditions.The pulsed plasma nitriding treatment was applied to AISI 304 austenitic stainless steel at different temperatures and durations.Results reveal that nitriding depth increased as process temperature and duration increase.The nitriding depth remarkably increased at 475℃for 8 h and at 550℃for 4 h.An austenite structure was transformed into a metastable nitrogen-oversaturated body-centered tetragonal expanded austenite(S-phase)during low-temperature plasma nitriding.The S-phase was converted to CrN precipitation at 475℃for 8 h and at 550℃for 4 h.Surface hardness and fatigue limit increased through plasma nitriding regardless of process conditions.The best surface hardness and fatigue limit were obtained at 550℃for 4 h because of the occurrence of CrN precipitation.

INTERFACIAL STRUCTURAL RELATIONSHIP BETWEENS'(Al_2CuMg) AND ALUMINUM

A clear understanding of the structure of the S precipitates which are present in Al-Li-X alloys is verp imporiant because the S -phase decreases the localization of strainand promotes less anisotropic properties during deformation. The close structural re-lationship between the S-phase and the Al matrix and their possible intedece bound-ary strvcture are described in detail. The proposed model is in good agreement with::::rimental obserwations. The dynamics Of the phase trunWrmation and possiblermation mechani8ms for the S,-phase are alSo proposed.

Correlation of BRD4 and Skp2 expression levels in ultrasound-guided thyroid nodule fine needle aspiration biopsy tissue with the pathological features of nodules

Objective:To study the correlation of bromodomain-containing protein 4(BRD4)and S-phase kinase-associated protein 2(Skp2)expression levels in ultrasound-guided thyroid nodule fine needle aspiration biopsy tissue with the pathological features of nodules.Methods:The tissues obtained in ultrasound-guided thyroid nodule fine needle aspiration biopsy in our hospital between March 2015 and March 2018 was selected and divided into malignant group and benign group according to the pathological results,and the expression levels of BRD4,Skp2,proliferation genes and angiogenesis genes were detected.Results:The BRD4 and Skp2 mRNA expression in thyroid nodules of the malignant group were significantly higher than those of the benign group,and the BRD4 and Skp2 mRNA expression in the malignant group of thyroid nodules with TNM III-IV,capsular invasion and lymph node metastasis were significantly higher than those in the thyroid nodules with TNM I-II,without capsular invasion and without lymph node metastasis;cyclin D1(CCND1),β-catenin,proliferation cell nuclear antigen(PCNA),vascular endothelial growth factor(VEGF),endothelial cell specific molecule-1(ESM-1),Survivin and cyclooxygenase 2(COX2)mRNA expression in thyroid nodules of the malignant group were obviously higher than those of the benign group and positively correlated with BRD4 and Skp2 while cyclin G2(CCNG2)and endostatin(ES)mRNA expression were significantly lower than those of the benign group and negatively correlated with BRD4 and Skp2.Conclusion:The high expression of BRD4 and Skp2 in malignant thyroid nodules is correlated with the pathological changes and can change the expression of proliferation genes and angiogenesis genes.