A novel colorimetric biosensor based on non-aggregated Au@Ag core–shell nanoparticles for methamphetamine and cocaine detection

We report a novel colorimetric biosensor based on non-aggregation Au@Ag core-shell nanoparticles to detect methamphetamine and cocaine. The biosensor consisted of a reporter probe (RP) that is a specific single-stranded DNA (ssDNA) sequence coated on Au@Ag nanoparticles, a capture probe (CP) conjugated with magnetic beads, and an illicit drug-binding DNA aptamer (Apt). Au@Ag nanoparticles were synthesized by seed growth and characterized by scanning electron microscope (SEM), high-resolution transmission electron microscopy (HR-TEM), and UV–vis spectra. Methamphetamine (METH) was used as an example to evaluate the feasibility of the biosensor and to optimize the detection conditions. We demonstrated that this sensing platform was able to detect as low as 0.1 nM (14.9 ng L−1) METH with a negligible interference from other common illicit drugs. Various concentrations of METH were spiked into urines, and the biosensor yielded recoveries more than 83.1%. In addition, the biosensor also showed a high sensitivity to detect cocaine. These results demonstrated that our colorimetric sensor holds promise to be implemented as a visual sensing platform to detect multiple illicit drugs in biological samples and environmental matrices

Rola edukacji i innowacji w promocji energii odnawialnej w krajach OECD i BRICS

Extreme climatic catastrophes and increasing emission levels demonstrate that humanity and nature are in confrontation. In this situation, the responsibility falls on intellectuals who engage in critical thinking, research, and innovation, propose solutions to problems, and bring society together to pursue a common goal. The present study assesses the role of education and Innovation in climate change mitigation in OECD and BRICS countries, where the use of renewable energy and decreasing the use of non-renewable energy are considered climate change mitigation strategies. The GMM approach is used to test the empirical model. The results indicate that increasing education and innovation levels in OECD and BRICS countries positively impact renewable energy consumption. However, the role of education and innovation in reducing the use of non-renewable energy consumption in the BRICS is insignificant, while in OECD countries, it is found significant. Thus, this study recommends that environmental education and green innovation be the focus to get sustainable development.Ekstremalne katastrofy klimatyczne i rosnące poziomy emisji zanieczyszczeń pokazują, że ludzkość i natura są w stanie konfrontacji. W tej sytuacji odpowiedzialność spada na intelektualistów, którzy angażują się w krytyczne myślenie, badania i innowacje, proponują rozwiązania problemów i jednoczą społeczeństwo w dążeniu do wspólnego celu. Niniejsze badanie ocenia rolę edukacji i innowacji w łagodzeniu zmian klimatu w krajach OECD i BRICS, gdzie wykorzystanie energii odnawialnej i zmniejszenie wykorzystania energii nieodnawialnej są uważane za strategie łagodzenia zmian klimatycznych. Do testowania modelu empirycznego zastosowano podejście GMM. Wyniki wskazują, że rosnący poziom edukacji i innowacyjności w krajach OECD i BRICS pozytywnie wpływa na zużycie energii odnawialnej. Jednak rola edukacji i innowacji w ograniczaniu zużycia energii nieodnawialnej w krajach BRICS jest znikoma, podczas gdy w krajach OECD jest uznawana za znaczącą. W związku z tym niniejsze badanie zaleca, aby edukacja środowiskowa i zielone innowacje były głównym celem osiągnięcia zrównoważonego rozwoju

Development of a new stroke scale in an emergency setting

Background: Early identification of stroke is crucial to maximize early management benefits in emergency departments. This study aimed to develop and validate a new stroke recognition instrument for differentiating acute stroke from stroke mimics in an emergency setting. Methods: A prospective observational cohort study among suspected stroke patients presenting to Emergency Department in the Second Affiliated Hospital of Guangzhou Medical University was conducted from May 2012 to March 2013. The symptoms and signs of suspected stroke patients were collected. Logistic regression analysis was used to identify the factors associated with acute stroke. The symptoms and signs closely associated with acute stroke were selected to develop the new stroke scale, Guangzhou Stroke Scale (GZSS). The diagnostic value of GZSS was then compared with ROSIER, FAST and LAPSS. The primary outcome was confirmed stroke by CT within 24 h. Results: Four hundred and sixteen suspected stroke patients (247 ischemia, 107 hemorrhage, 4 transient ischemic attack, 58 non-stroke) were assessed. A new stroke scale, GZSS (total score from −1 to 8.5), was developed and consisted of nine parameters: vertigo (−1), GCS ≤ 8 (+2), facial paralysis (+1), asymmetric arm weakness (+1), asymmetric leg weakness (+1), speech disturbance (+0.5), visual field defect (+1), systolic blood pressure ≥145 mmHg (+1) and diastolic blood pressure ≥95 mmHg (+1). Among the four scales, the discriminatory value (C-statistic) of GZSS was the best (AUC: 0.871 (p < 0.001) when compared to ROSIER (0.772), LAPSS (0.722) and FAST (0.699). At an optimal cut-off score of >1.5 on a scale from −1 to 8.5, the sensitivity and specificity of GZSS were 83.2 and 74.1 %, whilst the sensitivities and specificities of ROSIER were 77.7 and 70.7 %, FAST were 76.0 and 63.8 %, LAPSS were 56.4 and 87.9 %. Conclusion: GZSS had better sensitivity than existing stroke scales in Chinese patients with suspected stroke. Further studies should be conducted to confirm its effectiveness in the initial differentiation of acute stroke from stroke mimics. Keywords: Diagnosis, Stroke, Stroke mimics, ROSIER scale, FAST scale, LAPSS scale, Emergency department, China Abbreviations: AUC, area under the ROC curve; CT, computed tomography; DWI, diffusion weighted imaging; FAST, the face arm speech test; GCS, Glasgow Coma Scale; IQR, inter quartile range; LAPSS, the Los Angeles Prehospital Stroke Screen; MRI, magnetic resonance imaging; NIHSS, National Institute of Health stroke scale; OR, odds ratio; ROC, receiver operating characteristic; ROSIER, the Recognition of Stroke in the Emergency Room scale; TIA, transient ischemic attac

STEMI outcomes in Guangzhou and Hong Kong: two-centre retrospective interregional study

BACKGROUND AND OBJECTIVES:Healthcare systems are organized very differently in Hong Kong (HK) and Guangzhou (GZ). This study compared managements of the emergency departments (ED) and one-year mortalities of ST-segment elevation myocardial infarction (STEMI) patients in two teaching hospitals in Guangzhou and Hong Kong. METHODS:Retrospective observational study of STEMI mortalities and treatments in the Prince of Wales Hospital (PWH) and the Second Affiliated Hospital of Guangzhou Medical University (AHGZMU), was conducted between January and December 2010. The primary outcome was one-year all cause mortality. RESULTS:Univariate analysis of 76 cases from PWH and 111 cases from AHGZMU showed similar clinical characteristics, except for lower proportions of males (74% vs 92%, P = 0.002), hyperlipidemia (5% vs 25%, P67 years) and hyperglycemia (>10 mmol/L). Aged over 65 years, presence of anterior wall infarct, body weight ≤65 kg, SBP 10 mmol/L were the independent predictors of in-hospital MACE. CONCLUSION:There was no statistically significant difference between the standardized one-year all-cause mortalities of STEMI patients in the setting mainly using thrombolysis with shorter door-to-treatment time and the setting mainly using PCI with longer door-to-treatment time. Aged over 67 years and glucose level over 10 mmol/L were the independent predictors of one-year mortality. Older age, presence of anterior wall infarct, lower body weight, lower SBP at ED and hyperglycemia were the independent predictors of in-hospital MACE

Comparison of outcomes in emergency department patients with suspected cardiac chest pain: two-centre prospective observational study in Southern China

Background Hong Kong (HK) and Guangzhou (GZ) are cities in China with different healthcare systems. This study aimed to compare 30-day and 6-month mortality and characteristics of patients with suspected cardiac chest pain admitted to two emergency departments (ED) in HK and GZ. Methods A prospective observational study enrolled patients with suspected cardiac chest pain presenting to EDs in the Prince of Wales Hospital (PWH), HK and the Second Affiliated Hospital of Guangzhou Medical University (AHGZMU),GZ. The primary outcome was 30-day and 6-month mortality. Results In total, 996 patients were recruited, 407 cases from GZ and 589 cases from HK.The 30-day and 6-month mortality of chest patients were 3.7% and 4.7% in GZand 0.3% and 1.9% in HK, respectively. Serum creatinine level (Cr) was an independent factor for 30-day mortality whilst Cr and systolic blood pressure (SBP) were independent factors for 6-month mortality. In Cox regression analysis, unadjusted and adjusted hazard ratios for 30-day and 6-month mortality in GZ were significantly increased. Conclusion The 30-day and 6-month mortality of patients with suspected cardiac chest pain in Guangzhou were higher than in Hong Kong due to due to different baseline clinical characteristics of patients and different distributions of diagnoses, which were associated with different healthcare systems. Serum creatinine and SBP were independent factors for 30-day and 6-month mortality

Similar operation template attack on RSA-CRT as a case study

A template attack, the most powerful side-channel attack methods, usually first builds the leakage profiles from a controlled profiling device, and then uses these profiles to recover the secret of the target device. It is based on the fact that the profiling device shares similar leakage characteristics with the target device. In this study, we focus on the similar operations in a single device and propose a new variant of the template attack, called the similar operation template attack (SOTA). SOTA builds the models on public variables (e.g., input/output) and recovers the values of the secret variables that leak similar to the public variables. SOTA’s advantage is that it can avoid the requirement of an additional profiling device. In this study, the proposed SOTA method is applied to a straightforward RSA-CRT implementation. Because the leakage is (almost) the same in similar operations, we reduce the security of RSA-CRT to a hidden multiplier problem (HMP) over GF(q), which can be solved byte-wise using our proposed heuristic algorithm. The effectiveness of our proposed method is verified as an entire prime recovery procedure in a practical leakage scenario

Torque oscillation characteristics in the process of bobbin tool friction stir welding

This study analyzes torque oscillation characteristics in the process of bobbin tool friction stir welding. The empiral data of torque, the point temperature of contact surface and the leading point temperature is presented to explore the torque signal spectrum characteristics, the causes of the periodic oscillation of torque, the relationship between the oscillation and the surface forming of weld joint. The result shows that the torque in BTFSW has regular oscillation. The oscillation frequency of the torque is nearly 2 times the spindle frequency. With the increase of rotary speed, the oscillation frequency and the frequency difference increase gradually. There is no significant linear relationship between the amplitude peak of the torque, traveling speed, rotary speed and the measured point temperature. The instable temperature of the leading areas to be welded inevitably leads to the instability of the torque amplitude. The analysis indicates that the more intense of the heat input rate, the more obvious of the torque vibration, and the small and uniform torque amplitude does not affect the surface shape. Once the oscillation is abnormal, it easily leads to the poor surface forming and the hole defect