Single particle inductively coupled plasma mass spectrometry and its variations for the analysis of nanoparticles.

Single particle inductively coupled plasma mass spectrometry (spICPMS) can count and weigh metal-containing nanoparticles (NPs), enabling their sizing if their geometry, density, and composition are known. With a nebulizer and a spray chamber for sample introduction, both the sample uptake rate and the transport efficiency must be determined when calibrating with solutions. In contrast, flow injection (FI) and mono-segmented flow analysis (MSFA) coupled to spICPMS do not need determination of the transport efficiency and sample uptake rate for accurate NP mass measurement. Correcting for the significant settling time on some instruments is also discussed, as well as calibration through signal integration instead of averaging, which eliminates the need to measure the transport efficiency when seeking NP mass. Nitrogen added to the outer plasma gas can reduce the background for the determination of P, S, Ca and Fe. Infrared heating of the sample introduction system provides 100% transport efficiency, enabling accurate particle mass and concentration measurements without measurement of transport efficiency.

Serum cytokine analysis in a cohort of advanced non-small cell lung cancer treated with PD-1 inhibitors reveals predictive markers of CXCL12.

Background: The circulating predictive factors for the outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving immune checkpoint inhibitors (ICIs) remain elusive. We aimed to assess the predictive value of circulating cytokines for outcomes. Methods: Serum samples of 102 advanced-stage NSCLC patients who underwent immunotherapy were collected at baseline. The relative levels of 37 cytokines were detected. PD-L1 expression was also analyzed. Results: Higher serum CXCL12 levels (top 33%) were a poor predictive biomarker for durable clinical benefit (DCB) (23.5% vs. 72.1%, p<0.001), progression-free survival (PFS) (3.76 vs. 14.40 months; p<0.001) and overall survival (OS) (12.20 vs. 44.84 months; p=0.008). Compared with PD-L1-negative patients, PD-L1-positive patients had a significantly higher objective response rate (ORR) (70.0% vs. 28.8%, p<0.001) and a prolonged mPFS (25.35 vs. 4.64 months, p=0.003) and tended to have an increased mOS (44.84 vs. 20.42 months, p=0.087). A signature comprising PD-L1<1% and the top 33% CXCL12 level was associated with the lowest ORR (27.3% vs. 73.7%, p<0.001) and DCB (27.3% vs. 73.7%, p<0.001) and the worst mPFS (2.44 vs. 25.35 months, p<0.001) and mOS (11.97 vs. 44.84 months, p=0.007). Area under the curve (AUC) analyses of PD-L1 expression, CXCL12 level and PD-L1 expression plus CXCL12 level to predict DCB or no durable benefit (NDB) showed AUC values of 0.680, 0.719 and 0.794, respectively. Conclusion: Our findings suggest that serum cytokine CXCL12 levels can predict the outcomes of patients with NSCLC receiving ICI. Moreover, the combination of CXCL12 levels and PD-L1 status can predict outcomes with a significantly improved discriminatory power.

LncRNAs and related molecular basis in malignant pleural mesothelioma: Challenges and potential.

Malignant pleural mesothelioma (MPM) is a rare but invasive cancer, which mainly arises from mesothelial tissues of pleura, peritoneum and pericardium. Despite significant advances in treatments, the prognosis of MPM patients remains poor, and the 5-year survival rate is less than 10%. Therefore, it is urgent to explore novel therapeutic targets for the treatment of MPM. Growing evidence has indicated that long non-coding RNAs (lncRNAs) potentially could be promising therapeutic targets for numerous cancers. In this regard, lncRNAs might also potentially therapeutic targets for MPM. Recent advances have been made to investigate the molecular basis of MPM. This review first provides a comprehensive overview of roles of lncRNAs in MPM and then discusses the relationship between molecular basis of MPM and MPM-related lncRNAs to implement them as promising therapeutic targets for MPM.

Real-world treatment and prognostic factors for survival in ALK+ non-small cell lung cancer (NSCLC) patients with brain metastases in China.

BACKGROUND: To explore the efficacy and prognostic factors of different treatment modalities on anaplastic lymphoma kinase (ALK)+ non-small cell lung cancer (NSCLC) patients with brain metastases (BMs). METHODS: A total of 86 patients were enrolled into the study. They were divided into two cohorts based on their history of treatment with ALK tyrosine kinase inhibitors (ALK-TKIs) prior to the incidence of BMs. ALK-TKI-naïve patients with BMs were included in cohort 1 (n = 59); patients who developed BMs after ALK-TKIs treatment were enrolled in cohort 2 (n = 27). Prognostic factors related with overall survival (OS) when treated with ALK-TKIs were assessed in multivariable analysis. RESULTS: With a median follow-up of 41.8 months, the median OS was 34.8 months. In cohort 1, the OS, intracranial progression-free survival (iPFS), and progression-free survival (PFS) were 38.7 months (95% CI: 23.3 to 54.1), 18.5 months (95% CI: 9.6 to 27.4), and 19.1 months (95% CI: 13.7 to 24.5), respectively. Significantly improved OS and iPFS were noted in those patients in which second-generation ALK-TKIs versus crizotinib were initiated (OS: not reached vs. 29.0 months, p = 0.040; iPFS: 22.8 vs. 11.9 months, p = 0.035). In cohort 2, patients who experienced BMs as a result of the treatment failure of ALK-TKIs had a median OS of 27.1 months. Considerable duration of stable disease in patients with measurable BMs was observed (iPFS: 11.5 months, 95% CI: 4.4 to 18.6; PFS: 12.2 months, 95% CI: 3.2 to 21.1). CONCLUSION: Second-generation ALK-TKIs further improved the duration of intracranial response and survival in ALK+ NSCLC patients with BMs in a real-world setting. The potent intracranial efficacy of second-generation ALK-TKIs might generate the lowered urgency of local treatment.

[Effect of EPA on inflammatory response of human periodontal ligament fibroblasts induced by P. gingivalis LPS].

PURPOSE: To observe the effect of eicosapentaenoc acid (EPA) on the expression of inflammatory factors in human periodontal ligament fibroblasts (hPDLCs) induced by using lipopolysaccharides (LPS) of Porphyromonas gingivalis (P. gingivalis). METHODS: hPDLCs were cultured by using tissue block method, and the effects of different concentrations of EPA on the activity of hPDLCs cells were observed by MTT method. According to MTT results, the appropriate concentration of EPA was selected, and the expression of interleukin-6(IL-6), IL-8 and IL-1ß in hPDLCs induced by P.gingivalis LPS was detected by real time PCR and ELISA. The data were evaluated by SPSS 10.0 software package. RESULTS: 25-100 µmol/L EPA had no effect on the activity of hPDLCs cells, but could inhibit the expression of IL-6, IL-8 and IL-1ß induced by P. gingivalis LPS in a dose-dependent manner. CONCLUSIONS: EPA can inhibit the expression of inflammatory factors induced by P. gingivalis LPS without affecting cell activity, indicating that EPA has the possibility of anti-inflammatory treatment of periodontitis.

Tumor immune microenvironment and immunotherapy efficacy in BRAF mutation non-small-cell lung cancer.

Previous small-size studies reported BRAF-mutated NSCLC patients have comparable sensitivity to immune checkpoint inhibitors (ICIs). However, how BRAF mutation affects the tumor immune microenvironment (TIME) is unknown. We performed Nanostring-panel RNA sequencing to evaluate TIME in 57 BRAF mutated and wild-type (WT) NSCLC specimens (cohort A). The efficacy of ICI monotherapy or combined therapies was determined in 417 patients with WT and BRAF mutated NSCLC (cohort B). We found that BRAF-mutant tumors had similar ratios of CD8+ T cells to Tregs, the balance of cytotoxicity gene expression signatures and immune suppressive features, and similar ICI-response-related biomarkers to WT NSCLC. A similar TIME pattern was observed between the BRAF V600E and Non-V600E subgroups of NSCLC. The further retrospective study confirmed that treatment with ICI monotherapy or combined therapies resulted in similar overall survival (OS) (HR: 0.85; 95% CI, 0.56 to 1.30; p = 0.47) and progress-free survival (PFS) (HR: 1.02; 95% CI, 0.72 to 1.44; p = 0.91) of patients with WT (n = 358) and BRAF mutant (n = 59) NSCLC. Similarly, both patients with BRAF V600E or Non-V600E NSCLC had similar responses to immunotherapy. Our findings support that BRAF mutation did not modulate TIME in NSCLC and therapeutic responses to ICIs. Patients with NSCLC harboring BRAF mutation should not be denied treatment with ICIs.

Efficacy and Safety of Nasal Immunisation with Somatostatin DNA Vaccine for Growth Promotion in Fattening Pigs.

This study aimed to evaluate the efficacy and safety of the SS DNA vaccine on growing pigs. Randomly, 147 pigs were divided into four groups, treatment 1 (T1, 3 × 109 CFU/mL, n = 39), T2 (3 × 108 CFU/mL, n = 35), T3 (3 × 107 CFU/mL, n = 35) and control group (phosphate-buffered saline, n = 38). All animals received two vaccinations separated by 45 days and the same diet and management. The results showed that all treatment groups (T1, T2 and T3) had significantly higher slaughter weight (d 185) than the Ctrl group (p < 0.05), and daily gain between 50 and 110 days of age was significantly higher in all treatment groups than in the Ctrl group (p < 0.05). Antibody-positive pigs have significantly higher daily weight gain than that in antibody-negative pigs (p < 0.05). The results of the meat quality analysis showed no significant changes between the P (antibody-positive pigs) and N (antibody-negative pigs) groups. Furthermore, the results showed that antibody titres at 110 and 185 days had a significant positive correlation with the daily weight gain (p < 0.05) and a significant negative correlation with the backfat thickness (p < 0.05). Evaluating the safety of vaccines by PCR amplification of target genes (GS/2SS), faecal, soil and water samples had no target genes detected by PCR amplification in these samples after 5 days, and no GS/2SS were detected in the blood and tissues for the experimental period. Moreover, no abnormalities were found in pathological sections of the P group compared with the N group. In conclusion, SS DNA vaccines can promote the growth of fattening pigs to a certain extent without altering the meat quality, and it has no effects on the safety of the surrounding environment.

The Efficacy of PD-1/PD-L1 Inhibitors in Patients with Liver Metastasis of Non-Small Cell Lung Cancer: A Real-World Study.

BACKGROUND: A controversy exists regarding the efficacy of programmed death-1 (PD-1)/ programmed death ligand-1 (PD-L1) inhibitors for patients with non-small cell lung cancer (NSCLC) and liver metastases. Our study retrospectively evaluated the efficacy of PD-1/PD-L1 inhibitors in NSCLC patients with liver metastases. METHODS: This retrospective study included 1627 lung cancer patients who received immunotherapy. Among 648 patients who had advanced NSCLC and received PD-1/PD-L1 inhibitors, 61 had liver metastases and 587 did not have. We analyzed patient characteristics, progression-free survival (PFS) and overall survival (OS). An exploratory analysis of biomarkers including CD4, CD8 and CD68 for efficacy in patients with liver metastases was also performed. RESULTS: In liver metastasis patients receiving PD-1/PD-L1 inhibitors, the objective response rate (ORR) was 29.5%, the disease control rate (DCR) was 72.1%, PFS was 6.4 months and OS was 15.2 months, which were all worse than those of patients without liver metastases (ORR: 35.8%; DCR: 81.8%; PFS: 7.9 months, p = 0.001; OS: 20.6 months, p = 0.008). When compared to non-liver lesions, the ORR (26.2 vs. 39.3%) and DCR (75.4 vs. 88.5%) of liver lesions were lower. During the analysis of PD-L1 expression, 27 PD-L1-positive patients had a longer PFS than 21 patients in the negative group (p = 0.012). Being PD-L1 positive was the independent prognostic indicators for PFS (p = 0.006). Additionally, the PD-L1 and CD8 dual-positive group responded favorably to PD-1/PD-L1 inhibitors. CONCLUSIONS: PD-1/PD-L1 inhibitors are effective in liver metastasis-NSCLC patients. However, the efficacy is inferior when compared to those of patients without liver metastases. In NSCLC patients with liver metastases, PD-L1 expression and CD8+ T cell infiltration can predict the response of PD-1/PD-L1-directed immunotherapy.

Real-world utilization of PD-1/PD-L1 inhibitors with palliative radiotherapy in patients with metastatic non-small cell lung cancer.

BACKGROUND: Programmed cell death protein 1 (PD-1) blockade plus radiotherapy may be a promising strategy to improve the prognosis of patients with metastatic non-small cell lung cancer (NSCLC). However, the optimum combined scheme, treatment time of radiotherapy, and irradiated lesion have not been fully determined. METHODS: A total of 321 metastatic NSCLC patients treated with immunotherapy were identified. Among them, 107 patients received PD-1/PD-ligand 1 (PD-L1) inhibitors with radiotherapy, while the remaining cases did not receive radiotherapy. Data on overall survival (OS), progression-free survival (PFS), treatment response and adverse events were collected. Comparisons based on type of radiation, timing of radiotherapy and number of irradiated lesions were performed. RESULTS: The median OS in PD-1/PD-L1 inhibitors plus radiotherapy was longer than in nonradiotherapy (22.8 vs. 16.6 months, p = 0.022). The median PFS showed a similar trend in this study (9.4 vs. 6.2 months, p = 0.042). Moreover, the combined strategy demonstrated a superior disease control rate and abscopal control rate versus without radiotherapy (both p ≤ 0.001). Further multivariate analysis in the immunotherapy and radiotherapy groups revealed that age below 65 (p = 0.004), Eastern Cooperative Oncology Group performance scores of 0-1 (p = 0.001), oligometastasis (p = 0.006), concurrent combination (p = 0.002), and treated with SRT (p = 0.013) were associated with longer OS. There was a similar incidence of adverse events between the two groups (both p ≥ 0.05). CONCLUSIONS: The combination of PD-1/PD-L1 inhibitors plus palliative radiotherapy demonstrated favorable survival and good tolerability in metastatic NSCLC patients.

Comparative efficiency and safety of insulin degludec/aspart with insulin glargine in type 2 diabetes: a meta-analysis of randomized controlled trials.

Recent studies have found compared with insulin glargine (IGlar), insulin degludec/aspart (IDeg/Asp) may provide adequate glycemic control and prevent hypoglycemia events in type 2 diabetes mellitus (T2DM). Consequently, we performed a meta-analysis to appraise and compare the efficiency and safety of IDeg/Asp and IGlar in the treatment of T2DM. We sought the databases including PubMed, Embase, Scopus, Cochrane library to confirm related articles which inspected the effect of IDeg/Asp versus IGlar for the treatment of T2DM until May 2021. Finally, six randomized controlled trials (RCTs) of 1,346 patients were included. The results showed that IDeg/Asp significantly decreased the mean hemoglobin A1c (HbA1c) level but was prone to serious adverse events, and IGlar increased the nocturnal confirmed hypoglycemia events. Besides, there were no significant changes in other indicators, including mean fasting plasma glucose (FPG) level, nine-point self-measured plasma glucose (SMPG) level, and adverse events. What's more, we found that there was no significant difference in the occurrence of hypoglycemia overall, but our subgroup analysis of confirmed hypoglycemia revealed the population in this subgroup (duration of diabetes ≤11 years) might has its particularity effecting the hypoglycemia outcome. Concerning efficiency, IDeg/Asp may have advantages in controlling the mean HbA1c level. Regarding safety, IGlar might increase the risk of nocturnal confirmed hypoglycemia. Further evidence is needed to compare better the efficiency and safety of IDeg/Asp versus IGlar therapy.

The Novel Tumor Microenvironment-Related Prognostic Gene AIF1 May Influence Immune Infiltrates and is Correlated with TIGIT in Esophageal Cancer.

BACKGROUND: Esophageal carcinoma (EC) is the sixth most common cause of cancer-related mortality worldwide. Studying the associations of the tumor microenvironment (TME) with pathology and prognosis would illustrate the underlying mechanism of prognostic prediction and provide novel targets for immunotherapy in the treatment of EC. METHODS: Transcriptomic profiles of 159 EC patients were obtained from The Cancer Genome Atlas (TCGA) database. Stromal and immune scores were calculated using the ESTIMATE algorithm. Differentially expressed genes (DEGs) were identified by the optimal score cutoff. Functional enrichments were analyzed by DAVID, while prognostic genes were explored using the Kaplan-Meier method. Validation analysis was performed using immunohistochemistry in tissue microarrays containing samples from 145 EC patients. Multiplex immunofluorescence staining was performed to detect a panel of 6 immune markers, including T-cell immunoreceptor with Ig and ITIM domains (TIGIT), in 90 EC patients. RESULTS: Immune scores significantly increased with increasing age, while stromal scores were dramatically elevated with increasing tumor stage. Fifteen TME-related DEGs including allograft inflammatory factor 1 (AIF1) were identified as prognostic factors of EC. Furthermore, the validation cohort indicated that AIF1 was negatively associated with the prognosis of esophageal squamous cell carcinoma patients. Subsequent analyses suggested that AIF1 may affect immune infiltrates, including T cells and natural-killer cells. Moreover, a correlation between AIF1 and TIGIT was identified. CONCLUSIONS: These results indicate that the TME-related gene AIF1 is a promising predictor of prognosis and is related to immune infiltrates and TIGIT expression in EC. However, further mechanistic studies are needed.

Review: distributed time-domain sensors based on Brillouin scattering and FWM enhanced SBS for temperature, strain and acoustic wave detection.

Distributed time-domain Brillouin scattering fiber sensors have been widely used to measure the changes of the temperature and strain. The linear dependence of the temperature and strain on the Brillouin frequency shift enabled the distributed temperature and strain sensing based on mapping of the Brillouin gain spectrum. In addition, an acoustic wave can be detected by the four wave mixing (FWM) associated SBS process, in which phase matching condition is satisfied via up-down conversion of SBS process through birefringence matching before and after the conversion process. Brillouin scattering can be considered as the scattering of a pump wave from a moving grating (acoustic phonon) which induces a Doppler frequency shift in the resulting Stokes wave. The frequency shift is dependent on many factors including the velocity of sound in the scattering medium as well as the index of refraction. Such a process can be used to monitor the gain of random fiber laser based on SBS, the distributed acoustic wave reflect the distributed SBS gain for random lasing radiation, as well as the relative intensity noise inside the laser gain medium. In this review paper, the distributed time-domain sensing system based on Brillouin scattering including Brillouin optical time-domain reflectometry (BOTDR), Brillouin optical time-domain analysis (BOTDA), and FWM enhanced SBS for acoustic wave detection are introduced for their working principles and recent progress. The distributed Brillouin sensors based on specialty fibers for simultaneous temperature and strain measurement are summarized. Applications for the Brillouin scattering time-domain sensors are briefly discussed.

Efficacy of PD-1/PD-L1 inhibitors in patients with non-small cell lung cancer and brain metastases: A real-world retrospective study in China.

BACKGROUND: There is only limited knowledge of the treatment responses and clinical outcomes of immune checkpoint inhibitors (ICIs) in driver gene-negative non-small cell lung cancer (NSCLC) patients with brain metastases (BM). This study aims to assess the efficacy of immunotherapy in these patients in a real world setting. METHODS: NSCLC-BM patients without driver gene mutations who received ICIs were retrospectively identified between July 2017 and December 2019. The primary observation endpoint was intracranial objective response rate (iORR), and secondary objectives were objective response rate (ORR), intracranial and systemic progression-free survival (iPFS, PFS), and overall survival (OS). RESULTS: We reviewed 1578 patients with lung cancer and BM. According to the exclusion criteria, 41 patients were finally enrolled. Among these 41 patients, iORR was 36.6% (95% confidence interval [CI] = 21.2%-52.0%), whereas iPFS was 6.8 (95% CI = 3.32-10.35) months. Additionally, ORR, PFS, and OS were 24.4% (95% CI = 10.7%-38.1%), 6.2 (95% CI = 4.57-7.83) months and 13.7 (95% CI = 11.20-16.26) months, respectively. ICIs combined with concurrent radiotherapy group exhibited preferred iORR (p = 0.030) compared with no radiotherapy group, and ICIs plus chemotherapy showed improved OS (p = 0.024) compared to ICI monotherapy. Moreover, the lines of ICI treatment ≥2 (p = 0.005) and derived neutrophil-to-lymphocyte ratio (dNLR) ≥3 (p = 0.010) were independently negative factors for OS. CONCLUSION: In NSCLC-BMs patients lacking driver genes, ICIs exhibited an effective drug regime. A combination of ICIs with concurrent radiotherapy showed a better intracranial response, whereas ICIs plus chemotherapy were associated with superior OS.

Towards customized cancer vaccines: a promising filed in personalized cancer medicine.

INTRODUCTION: Cancer remains a major source of disease burden worldwide. Although cancer vaccines have been developed, most currently available cancer vaccines have limited therapeutic efficacy. Recent research using novel sequencing and bioinformatic tools has led scientists to realize that each tumor harbors a unique set of genetic mutations that can manifest as tumor-specific neoantigens. Therefore, it would be useful to develop personalized cancer vaccines that target neoantigens, which might improve the efficacy of these cancer treatments. AREAS COVERED: This review covers cancer vaccine development and the emerging field of personalized cancer vaccines, with a discussion of future clinical trials for this promising treatment strategy. EXPERT OPINION: Developing vaccines to treat tumors is one of the most promising and exciting fields in cancer research. However, cancer vaccines have shown limited efficacy in clinical trials for several decades, which may be related to the unique and complex processes underlying tumor development and progression. Recent studies have indicated that tumors express highly specific neoantigens, which are distinct from self-antigens. Thus, developing cancer vaccines that target these tumor-specific neoantigens is a promising strategy for developing personalized cancer vaccines.

High efficiency Brillouin random fiber laser with replica symmetry breaking enabled by random fiber grating.

We report a high efficiency Brillouin random fiber laser (BRFL) enabled by a random fiber grating (RFG) with demonstration of replica symmetry breaking (RSB). The RFG was characterized by optical coherence tomography (OCT) method, which measured the spatially resolved reflectivity of RFG by a tunable delay line. Multiple narrow linewidth peaks appeared in reflection spectrum of RFG, created by frozen scattering centers acting as narrow linewidth filters to select random modes in random fiber lasers based on Brillouin gain. With the scattering from RFG as disordered feedback, a BRFL with slope efficiency of 29.3% and lasing threshold of 10.2 mW was demonstrated with 1 kHz linewidth. Intensity dynamics show that RFG can reduce the noise of BRFL with a symmetric phase portrait, indicating the increased mean path length and coherence time of the Stokes photons. The probability distribution of the Parisi overlap parameter of intensity fluctuation spectra from trace to trace reveal a photonic spin-glass phase with RSB in the RFG enabled BRFL, providing a photonic platform to study the photon glassy behavior of random fiber lasers.

Random Fiber Grating Characterization Based on OFDR and Transfer Matrix Method.

Random fiber gratings (RFGs) have shown great potential applications in fiber sensing and random fiber lasers. However, a quantitative relationship between the degree of randomness of the RFG and its spectral response has never been analyzed. In this paper, two RFGs with different degrees of randomness are first characterized experimentally by optical frequency domain reflectometry (OFDR). Experimental results show that the high degree of randomness leads to low backscattering strength of the grating and strong strength fluctuations in the spatial domain. The local spectral response of the grating exhibits multiple peaks and a large peak wavelength variation range when its degree of randomness is high. The linewidth of its fine spectrum structures shows scaling behavior with the grating length. In order to find a quantitative relationship between the degree of randomness and spectrum property of RFG, entropy was introduced to describe the degree of randomness induced by period variation of the sub-grating. Simulation results showed that the average reflectivity of the RFG in dB scale decreased linearly with increased sub-grating entropy, when the measured wavelength range was smaller than the peak wavelength variation range of the sub-grating. The peak reflectivity of the RFG was determined by κ2LΔP (where κ is the coupling coefficient, L is the grating length, ΔP is period variation range of the sub-grating) rather than κL when ΔP is larger than 8 nm in the spatial domain. The experimental results agree well with the simulation results, which helps to optimize the RFG manufacturing processes for future applications in random fiber lasers and sensors.

Mode characteristic manipulation of random feedback interferometers in Brillouin random fiber laser.

The Brillouin random fiber laser (BRFL) suffers from high intensity noise that comes mainly from longitudinal mode beating at different mode frequencies. In this Letter, we propose and demonstrate that the mode characteristic of BRFL can be manipulated by distributed random feedback, which acts as the longitudinal mode filter. A theoretical model is developed for the first time, to the best of our knowledge, to analyze the mode characteristics of BRFL with different lengths of a weak fiber Bragg grating (FBG) array. In experiment, a single FBG, weak FBG array (reflection of $ - {40}\;{\rm dB}$-40dB) at various lengths, and a Rayleigh scattering fiber are used to provide the random feedback. Both theoretical analysis and experimental results show that single longitudinal mode operation can be realized with the distributed random feedback interferometer, leading to a stable temporal intensity output of the BRFL in the time domain.

Thermal and acoustic noise insensitive Brillouin random fiber laser based on polarization-maintaining random fiber grating.

Thermal and acoustic noises are crucial to the long-term stability of fiber lasers, as it introduces the fluctuation of optical path length on laser cavity, and hence imposing undesirable intensity noise and frequency drift, particularly for a random fiber laser with distributed Rayleigh scattering feedback from a long length fiber. In this Letter, we propose and demonstrate a thermal and acoustic noise insensitive Brillouin random fiber laser by utilizing the random feedback from a polarization-maintaining (PM) fiber-based random grating. A theoretical model is developed for the first time, to the best of our knowledge, to analyze environmental perturbation on the randomly induced refractive index modulation via a PM random grating. Both the theory and experiments show that the scattered optical intensity of the PM random fiber grating exhibits a weak dependence on the temperature fluctuation and the acoustic noise perturbation compared to that of the Rayleigh scattering from hundreds of meters of PM fibers, leading to the Brillouin random lasing radiation with a 20 dB relative intensity noise suppression in the frequency range from 10 Hz to 1 kHz.

Fingerprint Detection and Differentiation of Gas-phase Amines Using a Fluorescent Sensor Array Assembled from Asymmetric Perylene Diimides.

A series of structurally analogous PDIs were fabricated and used as fluorescent sensor arrays. Adjustment of the molecular electron-donating ability and polarity (i.e., chemical structure) was found to greatly influence the fluorescent quenching by different types of amines. Moreover, the sensor array displayed high sensitivity to amine vapors and allowed the fingerprint differentiation of different species.