A family history of prostate cancer (PrCa) is a strong risk factor for the disease, indicating that inherited factors are important in this disease. We previously estimated that about 2% of PrCa ...cases diagnosed ≤ 55 years harbour a BRCA2 mutation and PrCa among BRCA2 carriers has been shown to be more aggressive, with poorer survival.
To further evaluate the role of BRCA2 in PrCa predisposition, we screened 1864 men with PrCa aged between 36 and 88 years. We analysed the BRCA2 gene using a novel high-throughput multiplex fluorescence heteroduplex detection system developed for the ABI3130xl genetic analyzer.
We identified 19 protein-truncating mutations, 3 in-frame deletions and 69 missense variants of uncertain significance (UV) in our sample set. All the carriers of truncating mutations developed PrCa at ≤ 65 years, with a prevalence of BRCA2 mutation of 1.20% for cases in this age group.
Based on the estimated frequency of BRCA2 mutations in the United Kingdom we estimate that germline mutations in the BRCA2 gene confer an ∼ 8.6-fold increased risk of PrCa by age 65, corresponding to an absolute risk of ∼ 15% by age 65. These results suggest that routine testing of early onset PrCa cases for germline BRCA2 mutations will further help to refine the prevalence and risk associated with BRCA2 mutations and may be useful for guiding management options.
An indium tin oxide (ITO) thin film based saturable absorber (SA) is proposed and demonstrated for the operation of Q-switched pulse within the C-band region. The ITO was deposited through DC ...magnetron sputtering method. The thickness of ITO was 86.40 nm and it was measured using F20 Filmetrics. The deposited fiber ferrule was incorporated in an erbium-doped fiber (EDF) laser cavity for generating a stable Q-switching pulse. The generated output pulses displayed a repetition rate that ranged between 16.74 kHz and 38.03 kHz. The shortest pulse width retrieved was 5.78 µs at the maximum pump power of 165.5mW, while the maximum pulse energy recorded was 12.30 nJ. These results show that ITO has the potential to be used for pulsed laser applications.
Prostate cancer (PrCa) is one of the most common cancers affecting men but its aetiology is poorly understood. Family history of PrCa, particularly at a young age, is a strong risk factor. There have ...been previous reports of increased PrCa risk in male BRCA1 mutation carriers in female breast cancer families, but there is a controversy as to whether this risk is substantiated. We sought to evaluate the role of germline BRCA1 mutations in PrCa predisposition by performing a candidate gene study in a large UK population sample set.
We screened 913 cases aged 36–86 years for germline BRCA1 mutation, with the study enriched for cases with an early age of onset. We analysed the entire coding region of the BRCA1 gene using Sanger sequencing. Multiplex ligation-dependent probe amplification was also used to assess the frequency of large rearrangements in 460 cases.
We identified 4 deleterious mutations and 45 unclassified variants (UV). The frequency of deleterious BRCA1 mutation in this study is 0.45%; three of the mutation carriers were affected at age 65 years and one developed PrCa at 69 years. Using previously estimated population carrier frequencies, deleterious BRCA1 mutations confer a relative risk of PrCa of ~3.75-fold, (95% confidence interval 1.02–9.6) translating to a 8.6% cumulative risk by age 65.
This study shows evidence for an increased risk of PrCa in men who harbour germline mutations in BRCA1. This could have a significant impact on possible screening strategies and targeted treatments.
We introduce a new technique for manipulating silica gel particles suspended in a water-based solution using a stable mode-locked fiber laser (MDFL). We coated a side-polished fiber (SPF) with Au-NP ...which acts as a saturable absorber (SA). A stable MDFL was achieved at an operating wavelength of 1557.8 nm and a repetition rate of 60.8 MHz. The optical trapping of sub-micrometer-sized silica gel particles revealed remarkable characteristics of the optical force. This force was driven by the presence of surface plasmon polaritons (SPP) in the Au-NP SPF, which played a crucial role in facilitating the manipulation of silica gel particles. Specifically, the SPP generated a gradient optical force, propelling the particles toward the propagation region. Throughout the optical trapping process, we observed wavelength shifts towards higher values in the spectrum, ranging from 1557.8 to 1563.1 nm. To quantify the optical force, we conducted computational and experimental analyses, yielding a force range of 0.16 to 2.10 fN. The percentage errors associated with these measurements ranged from 3.37% to 7.48%. Importantly, simulation results closely align with the experimental findings, establishing a robust foundation for future applications.
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•A method for trapping silica gel particles in water with experimental and simulation.•The use of a stable MDFL with Au-NP SPF as a saturable absorber (SA).•Au-NP SPF MDFL trapping microparticles measured via wavelength shifts.
•Gold nanoparticle (Au-NP) coated with side polished fiber (SPF) as a saturable absorber (SA) for Q-switched fiber laser (QFL) generation.•Microparticle optical trapping of silica gel by Au-NP ...Q-switched fiber laser pulses is a new approach in research related to micrometer-sized objects and kept in good agreement with the simulation results.•A smaller optical force influences the silica gel's microparticle to trap.•Shifting of wavelength and frequency of Au-NP SPF QFL showing the proposed method enables absorption microparticle trapping.
This study demonstrates a method for microparticle optical trapping of silica gel using a stable Q-switched fiber laser (QFL) pulse. Gold nanoparticle (Au-NP) were fabricated as saturable absorbers on a side-polished optical fiber (SPF) to achieve stable QFL pulses of frequencies 25.81 kHz. Silica gel microparticles with a radius of 300–400 µm produced a dissimilar attractive trapping force based on the viscous drag exerted on the light field of the QFL. Shifts were observed at wavelengths of 1533.8–1541.0 nm and frequencies of 25.81–28.87 kHz. The validity of the numerical model is proven and the proposed model can be applied to examine the behavior of surface plasmon polaritons (SPP) modes in microparticle optical trapping. These findings confirm that the proposed system facilitates absorption microparticle trapping at the 1540 nm wavelength region.
Water-borne diseases are one of the major concerns in many countries. Particularly the presence of heavy metals inside the water resources can cause serious problems. In that perspective, current ...research is focused on the removal of copper (Cu2+) ions from aqueous solution by using polypyrrole. Synthesized polypyrrole before and after adsorption was analyzed by SEM equipped with EDX. The effect of important parameters on metal uptake has been investigated such as: dosage of the adsorbent, pH of the adsorption solution, contact time between adsorbent and contaminated water, and initial concentration of the copper ions. Furthermore, adsorption data corresponded well to the Langmuir isotherm model. Polypyrrole has proven to be an effective adsorbent that can be used not only for the removal of Cu2+ but also other heavy metal ions as well.
•Sputtered Au-NP coated on side-polished fiber as a saturable absorber for generating stable mode-locked erbium-doped fiber laser.•The various thickness of 10 nm, 20 nm, 30 nm, and 40 nm is applied ...for the generation of mode-locked erbium-doped fiber laser.•At 20 nm thickness produces a broader bandwidth of 10.8 nm with a higher repetition rate of 60.79 MHz and a pulse width of 403 fs.
This study introduces gold nanoparticles (Au-NPs) coated on side-polished fiber (SPF) as a saturable absorber (SA) material in the development of a mode-locked erbium-doped fiber laser (EDFL). The measurements were taken at various Au-NP thicknesses of 10, 20, 30, and 40 nm. The SPF was coated with Au-NPs using a Quorum sputter coater by varying the sputtering time of 100, 200, 300, and 400 s at the corresponding thicknesses of 10, 20, 30, and 40 nm. The mode-locked EDFL produced a consistent pulse train with pulse intervals of 25.77 ns, 16.45 ns, 17.92 ns, and 21.55 ns, corresponding to repetition rates of 38.90 MHz, 60.79 MHz, 55.80 MHz, and 46.49 MHz for Au-NP thicknesses of 10, 20, 30, and 40 nm, respectively. Thus, by its ability to tune the repetition rate and pulse duration at different Au-NP thicknesses, the Au-NP SPF SA shows great promise for future optical communications and optoelectronics applications.
This research demonstrates an erbium-doped fiber laser (EDFL) which was passively Q-switched by gold thin film saturable absorber (SA). A very simple technique was used to fabricate the SA, in which ...the gold was directly deposited on the fiber end face through DC magnetron sputtering at 120 mA of sputtering current. The SA was then inserted into the single ring cavity and achieved Q-switching at a threshold pump power of 38.8 mW. By gradually increasing the pump power from 38.8 mW to 119.3 mW, the repetition rate increases from 11.34 kHz to 21.72 kHz. Meanwhile, the pulse duration decreases from 13.91 us to 7.44 us. The maximum achievable pulse energy was 13.28 nJ. This research further expands the application of gold thin film S A to the field of Q-switched pulsed fiber laser.
A tunable Q-switched pulse erbium-doped fiber (EDF) laser using indium tin oxide (ITO) thin-film-based saturable absorber (SA) is proposed and demonstrated. The SA is formed by depositing an ITO ...layer using DC magnetron sputtering on the fiber ferrule, which can be easily fabricated in less than 200 s with thickness of 17.80 nm. The proposed tunable Q-switched pulse EDF laser is operated from 1540.0 to 1570.0 nm, covering a total wavelength of 30.0 nm. The generated output pulses displayed a repetition rate range between 21.70 and 94.34 kHz. The shortest pulse width retrieved is 3.22 µs at the maximum pump power of 378.6 mW, while the maximum pulse energy recorded is 30.29 nJ. To the best of the authors’ knowledge, this appears to be the first proposed tunable passively Q-switched pulse EDF laser using ITO that serves as SA, which can promote ITO film in the application of ultrafast photonics.
This work successfully demonstrated the tunable performance of a Q-switched pulse erbium-doped fiber laser (QPEDFL) using Indium Tin Oxide-Zinc Oxide (ITO-ZnO)-based SA. The ITO-ZnO is a material ...growth between transparent conducting oxides and transition metal oxides on a glass slide. The mechanical exfoliation technique is applied to serve the ITO-ZnO as SA and inserted in a single-ring cavity design. The QPEDFL in a single ring cavity gives the repetition rate, pulse width, average output power, pulse energy, and SNR of 38.49 kHz, 5.50 µs, 0.47 mW, 12.72 nJ, and 64.20 dB, respectively. Furthermore, the ITO-ZnO as SA provides a tuning range of 30.40 nm. By tuning the TBF, the wavelength changes from 1531.60 nm to 1562.0 nm, causing the pulse repetition rate and pulse width of the QPEDFL to vary from 41.50 kHz to 17.20 kHz, and 4.22 µs to 10.05 µs, respectively. According to the results obtained, it can confidently say the suggested pulse laser has potential in the application of optical communication systems as a light source.
•Transparent conducting oxide of ITO-ZnO is applied as SA using mechanical exfoliation technique.•The repetition rate, pulse width, average output power, pulse energy, and SNR of 38.03 kHz, 5.78 µs, 0.47 mW, 12.30 nJ, and 56.61 dB, respectively are exhibited without the presence of TBF in a laser cavity.•The ITO-ZnO as SA provides a tuning range of 30.40 nm.•ITO-ZnO has potential in the application of optical systems.
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