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Herein, highly efficient deoxyribonucleic acid (DNA) walking on electrode surfaces was realized by regulating DNA tracks, which was applied to construct an ultrasensitive electrochemiluminescent (ECL) biosensor for BCR/ABL fusion gene detection. The well-regulated DNA tracks were constructed via supersandwich hybridization chain reaction of two DNA strands (L1 and L2) to generate periodic linear dsDNA concatemers, where an exposed L1 domain closed with blocking strands (BS). The prepared DNA tracks were further assembled onto the surface of the Au nanoparticle-functionalized g-C3N4 nanohybrid (Au@g-C3N4 NHs)-modified electrode, achieving well-regulated interfacial tracks for the DNA walker. On this state, folic acid-labeled BS (FA-BS) were close to Au@g-C3N4 NHs, performing a quenched ECL emission. With existence of the BCR/ABL fusion gene, the target combined two walking DNA strands (WD1 and WD2) to form the bipedal DNA walkers, which walked on the well-regulated interfacial DNA tracks and replaced the FA-BS to light up the ECL emission, realizing DNA walker-based signal amplification. Compared to randomly constructed DNA tracks, the well-regulated DNA tracks reduced the kinetics barrier and fitted the step size of the DNA walker, thus promoting the DNA walking efficiency and decreasing the risk of interruption in the walking process. As a result, the designed DNA walker presented higher efficiency and capacity in signal amplification. Benefiting from this efficient DNA walker strategy, the ECL biosensor achieved sensitive detection of the BCR/ABL fusion gene with a detection limit of 0.18 fM. This smart strategy proposed a brief strategy to promote the working efficiency of the biosensor, which presented great application potential in clinical molecular diagnosis.

In this work, a brief electrochemical aptasensor was developed for highly sensitive detection of SARS-CoV-2 antigen utilizing an aptamer-binding induced multiple hairpin assembly strategy for signal amplification. In the presence of SARS-CoV-2, a pair of aptamers was brought in a close proximity according to the aptamer-protein antigen binding, which initiated strand displacement reaction thereby triggering a multiple hairpin assembly to obtain long linear DNA concatemers on the electrode surface. As the fabricated hairpin probes were labeled with biotin, massive streptavidin-alkaline phosphatases (ST-ALP) could be further introduced on the electrode interface via biotin-streptavidin interaction thus generating strong electrochemical signal in electrolyte solution containing 1-naphthol phosphate. Benefiting from the non-enzymatic multiple hairpin assembly signal amplification strategy, the designed aptasensor for SARS-CoV-2 spike protein detection exhibited the wide linear range from 50 fg·mL

In this work, Ti3C2Tx MXene was identified as efficient nanozyme with area-dependent electrocatalytic activity in oxidation of phenolic compounds, which originated from the strong adsorption effect between the phenolic hydroxyl group and the oxygen atom on the surface of Ti3C2Tx MXene flake. On the basis of the novel electrocatalytic activity, Ti3C2Tx MXene was combined with alkaline phosphatase to construct a novel cascading catalytic amplification strategy using 1-naphthyl phosphate (1-NPP) as substrate, thereby realizing efficient electrochemical signal amplification. Taking advantage of the novel cascading catalytic amplification strategy, an electrochemical biosensor was fabricated for BCR/ABL fusion gene detection, which achieved excellent sensitivity with linear range from 0.2 fM to 20 nM and limit of detection down to 0.05 fM. This biosensor provided a promising tool for ultrasensitive fusion gene detection in early diagnosis of chronic myelogenous leukemia and acute lymphocytic leukemia. Moreover, the manageable catalytic activity of MXene broke a path for developing nanozymes, which possessed enormous application potential in not only electrochemical analysis but also the extensive fields including organic synthesis, pollutant disposal and so on. Graphical Abstract

The opioid epidemic remains a significant public health challenge in the US. A catalyst for reducing the incidence of opioid-related harm could be the development and operationalization of patient risk stratification models. Prior work has focused on the statistical performance of such models, usually tailored to specific adverse events or sub-populations, without considering operational implications. A particular challenge in this context is predicting the most severe outcomes (fatal overdoses) due to imbalanced datasets. We develop a single population-level model for predicting a full range of adverse opioid-related events. We further explore the capacity requirements of interventions based on our model and address salient implementation trade-offs. We partner with Staten Island Performing Provider System to access claims data and electronic health records for the patient population on Staten Island. We develop a machine learning model for predicting adverse opioid-related outcomes. Subsequently, we conduct a rolling horizon analysis to evaluate the capacity requirements of intervention policies leveraging the model. Finally, we quantify the trade-off in predictive performance against concerns that arise in implementation, such as interpretability, data delay, and prediction horizon length. Our single model risk stratification framework achieves an Area Under the Receiver Operating characteristic Curve (AU-ROC) of 0.95, 0.87, 0.83 for the outcomes of any adverse opioid event, opioid overdose, and fatal opioid overdose, respectively. This model can be used to identify a small intervention cohort (1% of the highest-risk patients) which includes the majority (69%) of adverse opioid events. Our results suggest that predictive performance does not need to be sacrificed to satisfy implementation constraints. Accurate risk stratification models are operationally feasible for implementation, even in the absence of training data on fatal overdoses. The implementation of such models allows for targeted interventions with limited intervention capacity and in the presence of operational constraints.

In this work, a simple method for detecting ammonium persulfate using silver triangular nanoparticles (silver TNPs) was developed. Specifically, silver TNPs exhibited strong/appreciable surface plasmon resonance (SPR) signals at 670 nm, and low concentrations of ammonium persulfate could induce a decrease in the SPR of the silver TNPs and a change in their appearance from blue to colorless. Furthermore, it was also found that the SPR intensity was inversely proportional to the concentration of ammonium persulfate over the range of 0.10–0.70 mmol L−1, with a correlation coefficient of −0.9994. Recoveries for ammonium persulfate in spiked samples were in the range of 94.4–105.8%, and the relative standard deviations (RSDs) were in the range of 3.3–5.6%. Finally, a method for detecting ammonium persulfate using UV-Vis spectrophotometry was established and successfully applied to determining the concentration of ammonium persulfate in water-borne adhesives used in cigarettes.

A range of fatty acids (C 6 –C 11 ) coated magnetic nanoparticles were synthesized. The particle size and crystal phase of MNPs were characterized by transmission electron microscope and X-ray diffraction, respectively. The synthesized MNPs were used for adsorption of benzo( a )pyrene from water samples, the study showed that a proper chain length may accommodate BaP and/or provide enough Van der Waals interactions, so decanoic acid coated MNPs (Fe 3 O 4 @C 10 ) were selected for the adsorption experiments. The influences of amount of sorbent, the pH and ionic strength of sample matrix, temperature and sorption time on adsorption efficiency were investigated. The study showed that the characteristics of adsorption isotherms corresponded well with Freundlich model ( R 2 = 0.988), and the theoretical maximum adsorption capacity was 63.90 ng mg − 1 calculated by Langmuir model. Combined with high-performance liquid chromatography and fluorescence detection (HPLC–FLD), a simple and effective method for adsorption and determination of BaP in water samples was developed.

A sensitive and accurate method for the determination of chloride using citrate-stabilized silver triangular nanoplates was developed. Chloride caused a color change of silver triangular nanoplate solution from blue to yellow by fusion and etching, as confirmed by transmission electron microscopy and ultraviolet-visible absorption spectroscopy. The spectrophotometric determination involved measurement of the spectra involving localized surface plasmon resonance. The change in the ratio of absorption at 642 and 430 nanometers was proportional to the concentration of chloride from 0.10 to 0.30 millimolar with a correlation coefficient of 0.9977. To determine the feasibility of the method, cooling water was analyzed. Good recoveries were obtained with relative standard deviations of 3.09 to 5.42 percent. These results demonstrated that the method was accurate, reliable, and rapid for the determination of chlroide.

A simple and effective method based on magnetic solid-phase extraction combined with high performance liquid chromatography was used for the determination of hindered phenolic antioxidants in plastic packaging injections. The extraction and clean-up via Fe3O4@CTAB magnetic adsorbent dispersion in injections was followed by magnetic isolation and desorption of the analytes using acetonitrile. The cationic surfactant cetyltrimethylammonium bromide (CTAB) coated on the surface of Fe3O4 nanoparticles adsorbent was synthesized. The main parameters affecting the adsorption recoveries were evaluated and optimized, including the amounts of surfactant and adsorbent, pH, ionic strength, desorption conditions, and sample volume. Under the optimum conditions, the method was successfully applied to the determination of hindered phenolic antioxidants in plastic packaging injections. Low limits of detection (LODs) of 0.14 and 0.15 µg mL−1 and limits of quantification (LOQs) of 0.45 and 0.50 µg mL−1 were achieved. The mean recoveries were in the range from 85.0% to 93.5% at 5, 10, and 20 µg mL−1 spiked levels, and the relative standard deviations (RSDs) were in the range from 1.16% to 2.81%.

In this study, it was found that the ethyl acetate soluble fraction of Musa basjoo flowers was a rich source of antioxidant, due to its high total phenolic contents and significant antioxidant activity. Ten phenolic compounds were isolated from this plant. They are gallic acid (1), caffeic acid methyl ester (2), guaiacylglycerol (3), 3-(3,4-dihydroxyphenyl)-acrylic acid 1-(3,4-dihydroxyphenyl)-2-methoxy carbonyl ethyl ester (4), thero-guaiacylglycerol 8-O-β-d-glycopyranoside (5), quercitrin (6), buein (7), (2R, 3S)-5,7,3′,4′,5′-pentahydroxyflavanonol (8), isoquercitrin (9) and 1,7-bis(3,4-dihydroxyphenyl)-hepta-4E, 6E-dien-3-one (10). In addition, compounds 1, 2, 4, 6, 7, 8, 9 and 10 possessed potent strong free radical scavenging activity. Compounds 1 and 10 with powerful activity showed the higher content, implying important roles of 1 and 10 for the antioxidant activity of Musa basjoo flower. The study suggested that components of Musa basjoo flower possessed good antioxidant capacities and the species could be used in the prevention of diseases related to oxidant by-products of human metabolism.

Fewer than 9% of US hospitals had basic EHR systems as of 2008. The HITECH Act funded a multi-billion-dollar investment to close this gap requiring standards known as meaningful use (MU). The study was undertaken to assess whether this investment achieved the stated aims of MU; EHR adoption, lower cost and higher quality. The study is across-sectional, retrospective design; it employed two cohorts, MU vs. non-MU hospitals. Publicly reported, risk adjusted data from 4,221 hospitals (95%) on clinical, cost and safety metrics were analysed. The findings: EHR adoption by hospitals responded positively in response to incentives, rising from 8% to 55%. Quality outcomes showed 21,000 fewer deaths (p < 0.05) between the three clinical conditions (heart attack, heart failure, pneumonia). The HITECH Act had a positive return on investment with lower hospital cost per discharge of $327 (p < 0.05). The study results suggest hospitals with EHRs' that met MU standards demonstrate statistically significant mortality and cost improvement.

As an emerging application scenario of wireless technologies, vehicular communications have been initiated not only for enhancing the transportation safety and driving experiences, but also for a new commercial market of on-board Internet services. Due to extraordinarily high mobility of vehicles in a vehicular network, frequent handover requests will be a norm, which initiates the demand for an effective and fast authentication scheme that can maintain the service continuity in presence of the frequent handover events. However, previously reported authentication schemes, although with minimized handover latency and packet loss rate, may disclose the location information of the mobile user to the third party, which will seriously violate the location privacy of the user. In this paper, we propose a location privacy preserving authentication scheme based on blind signature in the elliptic curve domain. The scheme cannot only provide fast authentication, but also guarantee the security and location anonymity to the public. To analyze the proposed scheme, a theoretical traceability analysis is conducted, which shows that the probability of tracing an vehicle's route is negligibly small. We will also examine the authentication speed of the scheme, and show that the scheme can satisfy seamless handover for fast moving vehicles.

1016-3190/$ e see front matter Copyright 2011, Bu doi:10.1016/j.tcmj.2011.12.002 A 13-year-old boy was brought to a genetic counseling clinic for a tuberous sclerosis complex (TSC) gene test by hismother whowas affected by TSC. The boy’s mother had facial angiofibromas, multiple periungual fibromas, shagreen patches over her lower back, and hypomelanotic macules (ash leaf) over the left side of her waist (Fig. 1). The boy’s family history revealed that his 17-year-old brother was also affected by TSC with facial angiofibromas, a left index finger periungual fibroma, shagreen patches over the right lower abdomen, and de-pigmented lesions over the left lower back. Both the mother and the elder brother had their tuberous sclerosis 1 (TSC1) gene sequenced directly from peripheral blood leukocyte