Platelet Detection Based on Improved YOLO_v3.

Platelet detection and counting play a greatly significant role in medical field, especially in routine blood tests which can be used to judge blood status and diagnose related diseases. Therefore, platelet detection is valuable for diagnosing related blood diseases such as liver-related diseases. Blood analyzers and visual microscope counting were widely used for platelet detection, but the experimental procedure took nearly 20 minutes and can only be performed by a professional doctor. In recent years, technological breakthroughs in artificial intelligence have made it possible to detect red blood cells through deep learning methods. However, due to the inaccessibility of platelet datasets and the small size of platelets, deep learning-based platelet detection studies are almost nonexistent. In this paper, we carried out experiments for platelet detection based on commonly used object detection models, such as Single Shot Multibox Detector (SSD), RetinaNet, Faster_rcnn, and You Only Look Once_v3 (YOLO_v3). Compared with the other three models, YOLO_v3 can detect platelets more effectively. And we proposed three ideas for improvement based on YOLO_v3. Our study demonstrated that YOLO_v3 can be adopted for platelet detection accurately and in real time. We also implemented YOLO_v3 with multiscale fusion, YOLO_v3 with anchor box clustering, and YOLO_v3 with match parameter on our self-created dataset and, respectively, achieved 1.8% higher average precision (AP), 2.38% higher AP, and 2.05% higher AP than YOLO_v3. The comprehensive experiments revealed that YOLO_v3 with the improved ideas performs better in platelet detection than YOLO_v3.

Cohort, signaling, and early-career dynamics: The hidden significance of class in black-white earnings inequality.

A central tenet in the now classic Wilson hypothesis surrounding racial earnings inequality emphasizes the elevated labor-market challenges for black workers of limited productive assets, yet the empirical evidence on this issue remains inconclusive. In this article, drawing on the Panel Study of Income Dynamics (PSID), I uncover three mechanisms that tend to underestimate the difficulty facing lower segments of the black labor force: (1) the built-in bias of cross-sectional data that conflate career stages, (2) the cohort bias that concentrates on labor-market dynamics of a conservative era, and (3) the interplay between discrimination and productivity signaling that delivers heterogenous outcomes among black job seekers. When these mechanisms are accounted for, a pattern that is consistent with the Wilson hypothesis emerges - well-equipped African Americans see narrowed gaps in early-career earnings with Whites. These findings reconcile conflicting evidence in existence and provide guidance for future work.

A miniaturized giant magnetic resistance system for quantitative detection of methamphetamine.

Point-of-care testing (POCT) systems have been greatly developed in recent years. Among them, lateral flow immunoassay (LFIA) based on magnetic nanoparticles (MNPs) is widely used in various fields due to the advantages of small background noise and good biocompatibility. This paper designed an ultra-sensitive giant magnetic resistance (GMR) system for the quantitative detection of methamphetamine (MET). The system uses GMRs to detect the distribution of the magnetic field intensity of MNPs captured by the test (T) and control (C) lines on LFIA. A special external interference cancellation (EIC) method and a weak-signal waveform reconstruction method were used to improve the accuracy of the detection. Finally, the T/C ratio was calculated to realize the quantitative detection of MET. The result showed good linear performance with a detection limit of 0.1 ng mL-1. The system can also be used in other fields such as disease detection, food analysis, and environmental testing.

Anti-SARS-CoV-2 IgG and IgM detection with a GMR based LFIA system.

Since December 2019, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused millions of deaths and seriously threatened the safety of human life; indeed, this situation is worsening and many people are infected with the new coronavirus every day. Therefore, it is very important to understand patients' degree of infection and infection history through antibody testing. Such information is useful also for the government and hospitals to formulate reasonable prevention policies and treatment plans. In this paper, we develop a lateral flow immunoassay (LFIA) method based on superparamagnetic nanoparticles (SMNPs) and a giant magnetoresistance (GMR) sensing system for the simultaneously quantitative detection of anti-SARS-CoV-2 immunoglobulin M (IgM) and G (IgG). A simple and time-effective co-precipitation method was utilized to prepare the SMNPs, which have good dispersibility and magnetic property, with an average diameter of 68 nm. The Internet of Medical Things-supported GMR could transmit medical data to a smartphone through the Bluetooth protocol, making patient information available for medical staff. The proposed GMR system, based on SMNP-supported LFIA, has an outstanding advantage in cost-effectiveness and time-efficiency, and is easy to operate. We believe that the suggested GMR based LFIA system will be very useful for medical staff to analyze and to preserve as a record of infection in COVID-19 patients.

Quantitative detection of morphine based on an up-conversion luminescent system.

An up-conversion luminescent material converts low-frequency excitation light into high-frequency emission light through photons and has the advantages of long fluorescence lifetime, narrow emission peak and low toxicity; thus, this material has many unique applications in the detection and identification of biomolecules. In this study, an ultrasensitive up-conversion luminescent system for the quantitative detection of morphine was developed. The principle of this system is based on infrared light as an excitation light source to convert light with lower energy into excitation light with higher energy. The up-conversion luminescent material is used as a label and through the processing and analysis of the excitation light intensity, the quantitative detection of morphine concentration is achieved. At the same time, the excitation light can avoid the interference and scattering phenomenon of the autofluorescence of the biological sample, which improves the system's detection sensitivity. An algorithm for light intensity processing is added to process image data, reduce the interference caused by noise during image acquisition and improve the accuracy of morphine detection. The T/C value is calculated to achieve the quantitative detection of morphine with a detection limit of 0.1 ng mg-1 and detection time within 0.5 min. The up-conversion luminescent system has the advantages of quantitative detection, convenience, portability, short detection time and low price. Thus, the system can be used for the detection of other biomolecules or for other applications such as food analysis, environmental detection, national security, etc.

Biomarkers detection with magnetoresistance-based sensors.

Biosensing platforms for detecting and quantifying biomarkers have played an important role in the past decade. Among them, platforms based on magnetoresistance (MR) sensing technology are attractive. The resistance value of the material changes with the externally applied magnetic field is the core mechanism of MR sensing technology. A typical MR-based sensor has the characteristics of cost-effective, simple operation, high compactness, and high sensitivity. Moreover, using magnetic nanoparticles (MNPs) as labels, MR-based sensors have the ability to overcome the high background noise of complex samples, so they are particularly suitable for point-of-care testing (POCT). However, the problem still exists. How to obtain high-throughput, that is, multiple detections of biomarkers in MR-based sensors, thereby improving detection efficiency and reducing the burden on patients is an important issue in future work. This paper reviews three MR-based detection technologies for the detection of biomarkers, i.e., anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), and tunneling magnetoresistance (TMR). Based on these three common technologies, different typical applications that include biomedical diagnosis, food safety, and environmental monitoring are presented. Furthermore, the existing MR-based detection method is better expanded to make it more in line with present detection needs by combining different advanced technologies including microfluidics, Microelectromechanical systems (MEMS), and Immunochromatographic test strips (ICTS). And then, a brief discussion of current challenges and perspectives of MR-based sensors are pointed out.

A Framework for Explaining Black-White Inequality in Homeownership Sustainability.

To explain racially differential housing outcomes, previous studies have tended to concentrate on discriminatory processes within the mortgage market while ignoring homeowning families' broad socioeconomic challenges. This study proposes a conceptual framework for understanding Black-White inequality in homeownership sustainability, which emphasizes Black homeowners' socioeconomic challenges that are external to mortgage market evaluations, with a particular focus on the mediating role of liquid assets. Based on the Panel Study of Income Dynamics, the framework is put to an empirical test on the differential exit rates between Black and White homeowners in the United States during the recent housing crisis. The findings indicate that the racial gap in homeownership exit is eliminated after liquid wealth is controlled in the model alongside other covariates and that the inclusion of liquid wealth renders all mortgage-oriented variables nonsignificant with regard to their explanatory power for Black-White inequality in exit rates. Policy implications of the findings are also discussed.

Information feedback of 18F-FDG PET/CT computer imaging combined with tumor markers on recurrence and metastasis of non-small cell lung cancer.

To investigate the diagnostic value or information feedback of tumor markers combined with 18F-FDG PET/CT computer imaging on recurrence and metastasis of non-small cell lung cancer (NSCLC). METHODS: From January 2013 to December 2017, 95 NSCLC patients undergoing systemic 18F-FDG PET/CT computer imaging examination at the PET/CT computer imaging center of Mudanjiang Medical University had been enrolled. Typically, the interval between the completion of treatment and PET/CT computer imaging examination should be at least three months. Besides, all patients had undergone serum CEA monitoring before and after 18F-FDG PET/CT computer imaging, and 70 of them had received CYFRA21-1 test at the same time. Tumor markers were examined with PET/CT at intervals of less than one week, and all the feedback results were compared with clinical follow-up results or final pathology. Additionally, all the enrolled patients were followed up for 6-12 months. RESULTS: The sensitivity, accuracy, specificity, positive predictive value and negative predictive value of 18F-FDGPET/CT information feedback in evaluating recurrence or metastasis after NSCLC treatment were superior to those of common tumor markers, and the differences were statistically significant (P<0.05). Those of 18F-FDG PET/CT computer imaging combined with tumor marker examination for the recurrence and/or metastasis after NSCLC treatment were remarkably higher than those of either individual examination, and the accuracy difference of information feedback had significant statistical significance (P<0.05). Clearly, the diagnosis using tumor markers was correlated with that by 18F-FDG PET/CT imaging, and the correlation coefficient was r=0.63. Moreover, serum CEA was grouped at different levels, and the positive rate and accuracy of 18F-FDG PET/CT computer imaging diagnosis were increased with the increase in CEA level. 8 patients had received 18F-FDG PET/CT dual-phase examination, among them, 4 were diagnosed with recurrence or metastasis after MSCLC treatment, and all of them had been detected.

µ-NMR at the point of care testing.

NMR shows strong analytical capability for obtaining molecular information on materials and is used in a variety of fields. Micro-NMR (µNMR) is mainly based on low-field NMR (LF-NMR), which makes NMR detection portable and inexpensive. Point-of-care testing (POCT) has gradually become an area of major concern, and scientists have made much progress in applying µNMR systems for POCT. To the best of our knowledge, this is the first review of the latest development in miniaturization of µNMR systems. Then, we discuss cutting-edge µNMR-based applications in POCT and the outlook for future developments.

An application of RASER technique in the treatment of chronic total occlusion accompanied with stent fracture in right coronary artery: a case report.

BACKGROUND: The interventional treatment of chronic total occlusion (CTO) with stent fracture as well as severe calcification was extremely difficult and no effective technique has been reported. CASE PRESENTATION: A 50-year-old woman was hospitalized for angina, angiography revealed triple vessel disease, CTO accompanied with stent fracture in right coronary artery (RCA). Treatment using conventional coronary intervention was expected to be difficult. Therefore, we performed RASER technique, which was a combination of excimer laser coronary atherectomy (ELCA) with rotational atherectomy (RA), followed by the deployment of drug-eluting stents. Intravascular ultrasound (IVUS) revealed well attachment of the stents, the patient was discharged 3 days after the procedure and no recurrent chest discomfort was reported in a follow-up time of 10 months. CONCLUSION: This case report provided a first report of RASER technique in the treatment of CTO with stent fracture and severe calcification.

Fluctuating courses and constant challenges: The two trajectories of black-white earnings inequality, 1968-2015.

While rich literature exists on black-white earnings disparity, few studies differentiate the separate challenges facing different socioeconomic segments of the black population. Based on the Panel Study of Income Dynamics (PSID), this study explores the evolvement of black-white inequality in early-career earnings separately among college-educated and non-college-educated Americans from 1968 to 2015. The results indicate that while college-educated African Americans underwent fluctuating progress toward racial earnings equality, contingent on larger political and economic climates, African Americans of limited educational attainment experienced persistently wide earnings gaps with their white counterparts. By confirming the significance of social class on African-American economic outcomes, this study provides evidence in support of class-specific policy interventions toward racial equality. It also opens the door for subsequent research to explore specific mechanisms through which class-based racial disadvantages are operationalized.

Using magnetic susceptibility to evaluate pollution status of the sediment for a typical reservoir in northwestern China.

Intensive anthropogenic activities may add to pollution risks to lakes and rivers, which can be revealed by the magnetic characteristics of sediments. The present study aims to assess the pollution status of the sediment of a typical reservoir in northwestern China by application of magnetic susceptibility. The values of magnetic susceptibility exhibited significant positive correlations with trace metals (Co, Cu, Mn, Ni, and V) and natural radionuclides (232Th and 40K). Multivariate statistical analysis indicated common sources and similar deposition characteristics of magnetic particles and trace metals. It was conformed that magnetic susceptibility could be used as an indicator to identify industrial sources of trace metals, but was not suitable to indicate the traffic or natural sources. Linear regression equations between the low-frequency magnetic susceptibility and the integrated pollution index as well as annual effective dose rate indicated a potential for using magnetic susceptibility in semi-quantitative assessment of trace metal pollution and radiological hazard in sediments. A three-step procedure is proposed for the use of magnetic susceptibility in pollution monitoring, which provides a fast and effective method for estimating the pollution extent and tracing the major sources of trace metals in the sediment of lakes and rivers.

[Enhancing thermal stability of glucose oxidase by fusing amphiphilic short peptide].

Glucose oxidase catalyzes the oxidation of ß-D-glucose to gluconic acid and its derivatives, thus shows a great potential in the development of antibiotic-free feed. However, its production and processing still have the problem of poor thermal stability of enzyme activity. In this study, fusion of amphiphilic peptide technology was used to improve the stability of glucose oxidase. Herein, eight self-assembling peptides with different amino acid lengths and Linkers were fused to the N terminus of the glucose oxidase, yielding eight chimeric fusions SAP1-GS-GOD, SAP1-PT-GOD, SAP2-PT-GOD, SAP3-PT-GOD, SAP4-PT-GOD, SAP5-PT-GOD, SAP6-PT-GOD and SAP7-PT-GOD. Then, the 8 recombinant proteins were expressed in P. pastoris GS115. After separation and purification, the stability of glucose oxidase at 60 ℃was determined. The relative enzyme activities of the PT Linker-linked fusion enzyme incubated at 60 ℃ for 60 min were higher than those of the original enzyme, and the relative activity of SAP5-PT-GOD was 67% at 60 ℃ for 30 min, which was 10.9 times higher than that of the initial enzyme with the same treatment. Among them, the Kcat/Km value of SAP1-PT-GOD, SAP2-PT-GOD, SAP3-PT-GOD and SAP5-PT-GOD of the fusion enzyme was further improved than that of the initial enzyme. Through the analysis of the intramolecular force of the fusion enzyme, the increase of the thermal stability of the fusion enzyme is mainly due to the increase of the hydrogen bond. In summary, the study indicates that translational fusion of self-assembling peptides with PT Linker was able to augment the thermo-stability of glucose oxidase, which has certain potential in the production and application of glucose oxidase. The glucose oxidase with improved thermostability obtained in the above study and the related mechanism will play an important role in improving the activity of related enzymes in the proceeding of processing and application.

Investigating multiple dysregulated pathways in rheumatoid arthritis based on pathway interaction network.

The traditional methods of identifying biomarkers in rheumatoid arthritis (RA) have focussed on the differentially expressed pathways or individual pathways, which however, neglect the interactions between pathways. To better understand the pathogenesis of RA, we aimed to identify dysregulated pathway sets using a pathway interaction network (PIN), which considered interactions among pathways. Firstly, RA-related gene expression profile data, protein-protein interactions (PPI) data and pathway data were taken up from the corresponding databases. Secondly, principal component analysis method was used to calculate the pathway activity of each of the pathway, and then a seed pathway was identified using data gleaned from the pathway activity. A PIN was then constructed based on the gene expression profile, pathway data, and PPI information. Finally, the dysregulated pathways were extracted from the PIN based on the seed pathway using the method of support vector machines and an area under the curve (AUC) index. The PIN comprised of a total of 854 pathways and 1064 pathway interactions. The greatest change in the activity score between RA and control samples was observed in the pathway of epigenetic regulation of gene expression, which was extracted and regarded as the seed pathway. Starting with this seed pathway, one maximum pathway set containing 10 dysregulated pathways was extracted from the PIN, having an AUC of 0.8249, and the result indicated that this pathway set could distinguish RA from the controls. These 10 dysregulated pathways might be potential biomarkers for RA diagnosis and treatment in the future.

Natural radioactivity in reservoir sediment near an industrial park of northwest China.

The activity concentration of natural radionuclides in the sediment of a reservoir near an industrial park of northwest China was determined using gamma ray spectrometry. The activity concentrations of (226)Ra, (232)Th and (40)K in the investigated samples range from 30.2 to 37.5, 56.5 to 79.8 and 785.6 to 940.3 Bq kg(-1) with an average of 33.2, 71.8 and 866.2 Bq kg(-1), respectively, which are higher than the corresponding activity concentrations in the control sample. Radium equivalent activity, external hazard index, internal hazard index, indoor air absorbed dose rate and annual effective dose rate were calculated to assess the radiation hazards associated with the use of this sediment in the construction of dwellings. It was concluded that the radiation levels in the reservoir sediment do not give rise to radiological health concerns and the sediment can be safely used in the construction of buildings.

Survey and coping strategies for job stress of new nurses in pharmacy intravenous admixture service: a pilot study.

To survey the nurse stress and analyze stressors in new nurses from pharmacy intravenous admixture service (PIAS). A questionnaire survey referring to the revised stressor scale was carried out on 52 new nurses of PIAS in four hospitals in Harbin. The average stress score for all participants was 2.43±0.63, as medium level of stress. The stressors were classified into 6 categories: ensuring up-to-date knowledge of professional nursing skills, increased workload and work-time, interpersonal relationship, ensuring knowledge of equipments, attending educational programs, and decreased occupational demand. The most important stressors included fear of medical accident occurrence, fear of failure in performance assessment, fear of occupational injuries, feeling fatigue and lack of sleep. Considering the various kinds of stressors in the working places, it was necessary for managers' to use appropriate strategies to cope with the job stress in new nurses of PIAS.

[Study on change characters and correlations of iron, zinc and calcium in milk and blood of mother and infant at different stages].

OBJECTIVE: To assess the change characters of mineral status in breast milk and blood of lactating mothers and infants at different postpartum stages, and to analyze the clinic significance of these changes in breastfeeding. METHODS: 50 mother-infant pairs at 6 weeks postpartum and 50 mother-infant pairs at 3 months postpartum were randomly selected, and the concentration of iron, zinc and calcium in milk and blood of mothers and infants were measured according to flame atomic absorption spectrometry. Compared the disparity of these minerals at different stages, and analyze the correlations of the ones among milk, blood of mothers and infants. RESULTS: the level of iron and zinc declined through lactation(Fe 0.102 mg/100 g vs 0.0605 mg/100 g, P < 0.05; Zn 0.257 mg/100 g vs 0.171 mg/100 g, P < 0.05). The level of iron ion in blood of infants declined with increasing age (392.45 mg/L vs 356.80 mg/L, P < 0.05). The level of iron, zinc and calcium ion in maternal blood was not associated with these minerals of milk, and separately positively associated with these minerals in blood of infan (r = 0.591, 0.362 and 0.435, P = 0.000, 0.013 and 0.001). CONCLUSION: The mammary mineral transport is likely an active process, and not apparently associated with maternal mineral status. The decline of milk iron through lactation may be one of the reasons for high prevalence of breast-fed infants' physiologic anemia. Maternal mineral status during pregnancy may have an influence on the mineral levels of infants in early period.

Measurement of natural radioactivity and assessment of associated radiation hazards in soil around Baoji second coal-fired thermal power plant, China.

Activity concentrations of natural radionuclides (226)Ra, (232)Th and (40)K in soil around Baoji Second coal-fired thermal power plant of China were determined using gamma ray spectrometry. The mean activity concentrations of (226)Ra, (232)Th and (40)K in soil were found to be 40.3 ± 3.5, 59.6 ± 3.1 and 751.2 ± 12.4 Bq kg(-1), respectively, which are all higher than the corresponding average values in Shaanxi, Chinese and world soil. The radium equivalent activity (Ra(eq)), the air absorbed dose rate (D), the annual effective dose (E), the external hazard index (H(ex)) and internal hazard index (H(in)) were evaluated and compared with the internationally reported or reference values. All the soil samples have Ra(eq) lower than the limit of 370 Bq kg(-1) and H(ex) and H(in) less than unity. The overall mean outdoor terrestrial gamma air absorbed dose rate is ∼86.6 ± 3.4 nGy h(-1) and the corresponding outdoor annual effective dose is 0.106 ± 0.004 mSv, which is higher than the worldwide average (0.07 mSv y(-1)) for outdoor's annual effective dose.