Colorimetric sensing of copper(II) based on catalytic etching of gold nanoparticles

Based on the catalytic etching of gold nanoparticles (AuNPs), a label-free colorimetric probe was developed for the detection of Cu2+ in aqueous solutions. AuNPs were first stabilized by hexadecyltrimethylammonium bromide in NH3-NH4Cl (0.6 M/0.1 M) solutions. Then thiosulfate (S2O32-) ions were introduced and AuNPs were gradually dissolved by dissolved oxygen. With the further addition of Cu2+, Cu(NH3)(4)(2+) oxidized AuNPs to produce Au(S2O3)(2)(3-) and Cu(S2O3)(3)(5-), while the later was oxidized to Cu(NH3)(4)(2+) again by dissolved oxygen. The dissolving rate of AuNPs was thereby remarkably promoted and Cu2+ acted as the catalyst. The process went on due to the sufficient supply of dissolved oxygen and AuNPs were rapidly etched. Meanwhile, a visible color change from red to colorless was observed. Subsequent tests confirmed such a non-aggregation-based method as a sensitive (LOD= 5.0 nM or 032 ppb) and selective (at least 100-fold over other metal ions except for Pb2+ and Mn2+) way for the detection of Cu2+ (linear range, 10-80 nM). Moreover, our results show that the color change induced by 40 nM Cu2+ can be easily observed by naked eyes, which is particularly applicable to fast on-site investigations. (C) 2013 Elsevier B.V. All rights reserved.Based on the catalytic etching of gold nanoparticles (AuNPs), a label-free colorimetric probe was developed for the detection of Cu2+ in aqueous solutions. AuNPs were first stabilized by hexadecyltrimethylammonium bromide in NH3-NH4Cl (0.6 M/0.1 M) solutions. Then thiosulfate (S2O32-) ions were introduced and AuNPs were gradually dissolved by dissolved oxygen. With the further addition of Cu2+, Cu(NH3)(4)(2+) oxidized AuNPs to produce Au(S2O3)(2)(3-) and Cu(S2O3)(3)(5-), while the later was oxidized to Cu(NH3)(4)(2+) again by dissolved oxygen. The dissolving rate of AuNPs was thereby remarkably promoted and Cu2+ acted as the catalyst. The process went on due to the sufficient supply of dissolved oxygen and AuNPs were rapidly etched. Meanwhile, a visible color change from red to colorless was observed. Subsequent tests confirmed such a non-aggregation-based method as a sensitive (LOD= 5.0 nM or 032 ppb) and selective (at least 100-fold over other metal ions except for Pb2+ and Mn2+) way for the detection of Cu2+ (linear range, 10-80 nM). Moreover, our results show that the color change induced by 40 nM Cu2+ can be easily observed by naked eyes, which is particularly applicable to fast on-site investigations. (C) 2013 Elsevier B.V. All rights reserved

Predicting burst pressure of radiofrequency-induced colorectal anastomosis by bio-impedance measurement

The present study investigates the relationship between bio-impedance and burst pressure of colorectal anastomosis created by radiofrequency (RF)-induced tissue fusion. Colorectal anastomosis were created with ex-vivo porcine colorectal segments, during which 5 levels of compression pressure were applied by a custom-made bipolar prototype, with 5 replicate experiments at each compression pressure. Instant anastomotic tensile strength was assessed by burst pressure. Bio-impedance of fused tissue was measured by Impedance Analyzer across frequency that 100Hz to 3MHz. Statistical analysis shows only a weak correlation between bioimpedance modulus and burst pressures at frequency of 445 kHz (ρs= -0.426, P=0.099>0.05). In contrast, results demonstrated a highly significant negative correlation between reactance modulus and burst pressures (ρs= -0.812, P=0.000<0.05). The decrease in mean reactance modulus with increasing burst pressures was highly significant (p=0.019<0.05). The observed strong negative correlation between reactance modulus and burst pressures at frequency of 445 kHz indicates that reactance is likely to be a good index for tensile strength of RF-induced colorectal anastomosis, and should be considered for inclusion in a feedback loops in devices design

Stabilizing Sharpness-aware Minimization Through A Simple Renormalization Strategy

Recently, sharpness-aware minimization (SAM) has attracted a lot of attention because of its surprising effectiveness in improving generalization performance.However, training neural networks with SAM can be highly unstable since the loss does not decrease along the direction of the exact gradient at the current point, but instead follows the direction of a surrogate gradient evaluated at another point nearby. To address this issue, we propose a simple renormalization strategy, dubbed StableSAM, so that the norm of the surrogate gradient maintains the same as that of the exact gradient. Our strategy is easy to implement and flexible enough to integrate with SAM and its variants, almost at no computational cost. With elementary tools from convex optimization and learning theory, we also conduct a theoretical analysis of sharpness-aware training, revealing that compared to stochastic gradient descent (SGD), the effectiveness of SAM is only assured in a limited regime of learning rate. In contrast, we show how StableSAM extends this regime of learning rate and when it can consistently perform better than SAM with minor modification. Finally, we demonstrate the improved performance of StableSAM on several representative data sets and tasks.Comment: 31 page

Development and validation of a novel nomogram model for identifying risk of prolonged length of stay among patients receiving free vascularized flap reconstruction of head and neck cancer

BackgroundThe aim of the present study was to build and internally validate a nomogram model for predicting prolonged length of stay (PLOS) among patients receiving free vascularized flap reconstruction of head and neck cancer (HNC).MethodsA retrospective clinical study was performed at a single center, examining patients receiving free vascularized flap reconstruction of HNC from January 2011 to January 2019. The variables were obtained from the electronic information system. The primary outcome measure was PLOS. Univariate and multivariate analyses were used to find risk factors for predicting PLOS. A model was then built according to multivariate results. Internal validation was implemented via 1000 bootstrap samples.ResultsThe study included 1047 patients, and the median length of stay (LOS) was 13.00 (11.00, 16.00) days. Multivariate analysis showed that flap types ((radial forearm free flap (odds ratio [OR] = 2.238; 95% CI, 1.403-3.569; P = 0.001), free fibula flap (OR = 3.319; 95% CI, 2.019-4.882; P < 0.001)), duration of surgery (OR = 1.002; 95% CI, 1.001-1.003; P = 0.004), postoperative complications (OR = 0.205; 95% CI, 0.129-0.325; P = P < 0.001) and unplanned reoperation (OR = 0.303; 95% CI, 0.140-0.653; P = 0.002) were associated with PLOS. In addition to these variables, blood transfusion was comprised in the model. The AUC of the model was 0.78 (95% CI, 0.711–0.849) and 0.725 (95% CI, 0.605–0.845) in the primary and internal validation cohorts, respectively. The DCA revealed the clinical utility of the current model when making intervention decisions within the PLOS possibility threshold range of 0.2-0.8.ConclusionsOur study developed a nomogram that exhibits a commendable level of accuracy, thereby aiding clinicians in assessing the risk of PLOS among patients receiving free vascularized flap reconstruction for HNC

Precise Measurements of Branching Fractions for Ds+D_s^+ Meson Decays to Two Pseudoscalar Mesons

We measure the branching fractions for seven $D_{s}^{+}$ two-body decays to pseudo-scalar mesons, by analyzing data collected at $\sqrt{s}=4.178\sim4.226$ GeV with the BESIII detector at the BEPCII collider. The branching fractions are determined to be $\mathcal{B}(D_s^+\to K^+\eta^{\prime})=(2.68\pm0.17\pm0.17\pm0.08)\times10^{-3}$, $\mathcal{B}(D_s^+\to\eta^{\prime}\pi^+)=(37.8\pm0.4\pm2.1\pm1.2)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+\eta)=(1.62\pm0.10\pm0.03\pm0.05)\times10^{-3}$, $\mathcal{B}(D_s^+\to\eta\pi^+)=(17.41\pm0.18\pm0.27\pm0.54)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+K_S^0)=(15.02\pm0.10\pm0.27\pm0.47)\times10^{-3}$, $\mathcal{B}(D_s^+\to K_S^0\pi^+)=(1.109\pm0.034\pm0.023\pm0.035)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+\pi^0)=(0.748\pm0.049\pm0.018\pm0.023)\times10^{-3}$, where the first uncertainties are statistical, the second are systematic, and the third are from external input branching fraction of the normalization mode $D_s^+\to K^+K^-\pi^+$. Precision of our measurements is significantly improved compared with that of the current world average values

Silicon carbide for integrated photonics

The recent progress in chip-scale integrated photonics has stimulated the rapid development of material platforms with desired optical properties. Among the different material platforms that are currently investigated, the third-generation semiconductor, silicon carbide (SiC), offers the broadest range of functionalities, including wide bandgap, high optical nonlinearities, high refractive index, and CMOS-compatible device fabrication process. Here, we provide an overview of SiC-based integrated photonics, presenting the latest progress on investigating its basic optical and optoelectronic properties, as well as the recent developments in the fabrication of several typical approaches for light confinement structures that form the basic building blocks for low-loss, high functional and industry-compatible integrated photonic platform. Moreover, recent works employing SiC as optically-readable spin hosts for quantum information applications are also summarized and discussed. As a still-developing integrated photonic platform, the prospects and challenges of SiC material platform in the field of integrated photonics are also discussed, followed by potential solutions.Comment: 47pages, 15 figure

Clinical and GAA gene mutation analysis in mainland Chinese patients with late-onset Pompe disease: identifying c.2238G > C as the most common mutation

Background: Pompe disease is an autosomal recessive lysosomal glycogen storage disorder that has been reported in different ethnic populations which carry different common mutations of the acid alpha-glucosidase (GAA) gene. The GAA mutation pattern in mainland Chinese patients with late-onset Pompe disease is still not well understood. Methods: We presented the clinical and genetic characteristics of 27 mainland Chinese late-onset Pompe patients from 24 families. Results: GAA mutation analysis revealed 26 different mutations, including 10 that were novel. The allelic frequency of c.2238G > C (p.W746C) was found to be 27.08% in this patient group. Respiratory dysfunction was diagnosed in 10 of 11 patients who underwent pulmonary function evaluation, although only four required ventilator support at night. Conclusions: Our findings indicate that c.2238G > C (p.W746C) is the most common mutation in mainland Chinese late-onset Pompe patients, as observed in Taiwanese patients. The novel mutations identified in this study expand the genetic spectrum of late-onset Pompe disease, and the prevalence of respiratory dysfunction highlights the importance of monitoring pulmonary function in late-onset Pompe patients.Genetics & HereditySCI(E)[email protected]

Seismic Data Interpolation based on Denoising Diffusion Implicit Models with Resampling

The incompleteness of the seismic data caused by missing traces along the spatial extension is a common issue in seismic acquisition due to the existence of obstacles and economic constraints, which severely impairs the imaging quality of subsurface geological structures. Recently, deep learning-based seismic interpolation methods have attained promising progress, while achieving stable training of generative adversarial networks is not easy, and performance degradation is usually notable if the missing patterns in the testing and training do not match. In this paper, we propose a novel seismic denoising diffusion implicit model with resampling. The model training is established on the denoising diffusion probabilistic model, where U-Net is equipped with the multi-head self-attention to match the noise in each step. The cosine noise schedule, serving as the global noise configuration, promotes the high utilization of known trace information by accelerating the passage of the excessive noise stages. The model inference utilizes the denoising diffusion implicit model, conditioning on the known traces, to enable high-quality interpolation with fewer diffusion steps. To enhance the coherency between the known traces and the missing traces within each reverse step, the inference process integrates a resampling strategy to achieve an information recap on the former interpolated traces. Extensive experiments conducted on synthetic and field seismic data validate the superiority of our model and its robustness on various missing patterns. In addition, uncertainty quantification and ablation studies are also investigated.Comment: 14 pages, 13 figure

Esophageal stricture complicated with cardia cancer after endoscopic injection sclerotherapy for esophago-gas-tric fundal varices rupture bleeding: a case report

Cardia cancer patients complicated with cirrhosis，hypersplenism，and portal hypertension constantly have contraindications to systemic drugs such as chemotherapy due to poor liver function，and surgery has become the preferred treatment for patients with such cardia tumors. Evaluation of surgical indications，optimization of surgical regimen，and perioperative management strategy are key factors for safe and successful implementation of these surgeries. Here，we reported a 65-year-old male patient undergoing laparoscopic splenectomy plus pericardiac vascularization combined with radical resection of cardiac carcinoma. Satisfactory clinical efficacy was obtained. He could eat semi-liquid diet at 2 weeks after surgery. During over 1-year follow-up，the patient was generally in good condition，could eat normal diet，and the white blood cell，red blood cell and platelet were restored normal. Liver function was normal，and no thrombosis was seen on portal ultrasound. This case prompts that for cardia cancer patients complicated with cirrhosis，hypersplenism，esophago-gas-tric fundal varices，esophageal stricture，this surgical regimen provides novel therapeutic ideas，which can be utilized as a safe and effective treatment option