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Abstract Resonant Raman study reveals the noticeable effect of the ligand exchange on the nanocrystal (NC) surface onto the phonon spectra of colloidal CdTe NC of different size and composition. The oleic acid ligand exchange for pyridine ones was found to change noticeably the position and width of the longitudinal optical (LO) phonon mode, as well as its intensity ratio to overtones. The broad shoulder above the LO peak frequency was enhanced and sharpened after pyridine treatment, as well as with decreasing NC size. The low-frequency mode around 100 cm-1 which is commonly related with the disorder-activated acoustical phonons appears in smaller NCs but is not enhanced after pyridine treatment. Surprisingly, the feature at low-frequency shoulder of the LO peak, commonly assigned to the surface optical phonon mode, was not sensitive to ligand exchange and concomitant close packing of the NCs. An increased structural disorder on the NC surface, strain and modified electron-phonon coupling is discussed as the possible reason of the observed changes in the phonon spectrum of ligand-exchanged CdTe NCs. PACS: 63.20.-e, 78.30.-j, 78.67.-n, 78.67.Bf

Abstract Background Tandemly Repeated DNA represents a large portion of the human genome, and accounts for a significant amount of copy number variation. Here we present a genome wide analysis of the largest tandem repeats found in the human genome sequence. Results Using Tandem Repeats Finder (TRF), tandem repeat arrays greater than 10 kb in total size were identified, and classified into simple sequence e.g. GAATG, classical satellites e.g. alpha satellite DNA, and locus specific VNTR arrays. Analysis of these large sequenced regions revealed that several "simple sequence" arrays actually showed complex domain and/or higher order repeat organization. Using additional methods, we further identified a total of 96 additional arrays with tandem repeat units greater than 2 kb (the detection limit of TRF), 53 of which contained genes or repeated exons. The overall size of an array of tandem 12 kb repeats which spanned a gap on chromosome 8 was found to be 600 kb to 1.7 Mbp in size, representing one of the largest non-centromeric arrays characterized. Several novel megasatellite tandem DNA families were observed that are characterized by repeating patterns of interspersed transposable elements that have expanded presumably by unequal crossing over. One of these families is found on 11 different chromosomes in >25 arrays, and represents one of the largest most widespread megasatellite DNA families. Conclusion This study represents the most comprehensive genome wide analysis of large tandem repeats in the human genome, and will serve as an important resource towards understanding the organization and copy number variation of these complex DNA families.

In order to solve the problems of difficult feature extraction and low recognition rate of radar signal at low signal-to-noise ratios, a dual channel convolutional neural network model based on Choi-Williams distribution (CWD) and multisynchrosqueezing transform (MSST) is proposed, which obtains two-dimensional time-frequency images by CWD and MSST time-frequency analyses on radar signals. Respectively, the time-frequency images are preprocessed and sequencely fed to a dual channel convolutional neural network for deep feature extraction. Finally, the features acquired by the two channels are fused, and the radar signal is classified and recognized through the convolutional neural network classifier. The simulation results show that when the signal-to-noise ratio is -10 dB, the overall recognition accuracy can reach above 96%, which is excellent at low signal-to-noise ratios.

In order to comprehensively evaluate the driver's vibration comfort under different vibration conditions, eighteen subjects were required to drive a tractor at different speeds on field and asphalt roads respectively in the real vehicle experiment. The sEMG signals and vibration acceleration signals of the subjects were recorded. And the time-frequency domain analysis of sEMG signals and acceleration signals were used to determine the relationship among the characteristic indexes, tractor speed and road surfaces. The relevance analysis showed that there was a significant correlation between the integral electromyography (iEMG) and median frequency (MF) of the middle scalene muscle, erector spinae muscle and gastrocnemius muscle, the RMS of weighted acceleration (aw) of the neck, waist and legs, and the subjective comfort feelings. It was proven that the tractor speed had a significant impact on human body vibration based on the ANOVA result (p < 0.05). With the increase of running speed, the time domain indexes of sEMG signals including iEMG, RMS and the vibration acceleration signals of the testing body parts increased significantly, while the amplitudes of frequency domain indexes decreased. Therefore, a quantitative regression evaluation model for the comfort of the neck, waist and legs integrating the sEMG and vibration signals was established, and its relative errors were 5.05, 4.38 and 6.12% respectively. This proposed assessment model can combine characteristics of the partial and overall vibration response of human body effectively, predict the tractor driver's vibration comfort accurately, provide a theoretical basis for the evaluation of tractor cab vibration comfort. [ABSTRACT FROM AUTHOR]

In the field of armored vehicles, up to 70% of accidents are associated with low levels of situational awareness among the occupants, highlighting the importance of situational awareness in improving task performance. In this study, we explored the mechanisms influencing situational awareness by simulating an armored vehicle driving platform with 14 levels of experimentation in terms of five factors: experience, expectations, attention, the cueing channel, and automation. The experimental data included SART and SAGAT questionnaire scores, eye movement indicators, and electrocardiographic and electrodermal signals. Data processing and analysis revealed the following conclusions: (1) Experienced operators have higher levels of situational awareness. (2) Operators with certain expectations have lower levels of situational awareness. (3) Situational awareness levels are negatively correlated with information importance affiliations and the frequency of anomalous information in non-primary tasks. (4) Dual-channel cues lead to higher levels of situational awareness than single-channel cues. (5) Operators' situational awareness is lower at high automation levels. [ABSTRACT FROM AUTHOR]

With the development of technology, future tractors will become more intelligent. More complex interfaces and several control components tend to cause drivers' cognitive load to be easily overloaded. Therefore, an evaluation method of the control interface should be proposed from the cognitive load perspective. To realise this concept, first, the influence of the design elements of the interface on behaviour time was investigated and a behaviour time model was established. Consequently, the experimental data could be well fitted by the model (R2 > 0.9), and the behaviour time of the operating interfaces could be effectively predicted. Second, an evaluation index of the interface was proposed based on behaviour time, which could evaluate the interface's design level. Finally, the validity of the evaluation method was verified. The results provide theoretical guidance for human–machine interfaces for tractors from the perspective of drivers' cognitive load. [ABSTRACT FROM AUTHOR]

* Context.--Clinical responses to anti-programmed death receptor-1 and anti-programmed death ligand-1 (PD-L1) agents are generally improved in patients with high PD-L1 expression compared with those with low/negative ex pression across several tumor types, including urothelial carcinoma. Objective.--To validate a PD-L1 immunohistochemical diagnostic test in urothelial carcinoma patients treated with the anti-PD-L1 monoclonal antibody durvalumab. Design.--The Ventana PD-L1 (SP263) assay was validated for intended use in urothelial carcinoma formalin-fixed, paraffin-embedded samples in studies addressing sensitivity, specificity, robustness, and precision, and implemented in study CD-ON-MEDI4736-1108 (NCT01693562). Efficacy was analyzed in patients classified according to prespecified PD-L1 expression cutoffs: PD-L1 high (if > 1% of the tumor area contained tumor-associated immune cells, [greater than or equal to] 25% of tumor cells or [greater than or equal to] 25% of immune cells stained for PD-L1; if [less than or equal to] 1% of the tumor area contained immune cells, [greater than or equal to] 25% of tumor cells or 100% of immune cells stained for PD-L1) and PD-L1 low/negative (did not meet criteria for PD-L1 high). Results.--The assay met all predefined acceptance criteria for sensitivity, specificity, and precision. Interreader and intrareader precision overall agreement were 93.0% and 92.4%, respectively. For intraday reproducibility and inter-day precision, overall agreement was 99.2% and 100%, respectively. Interlaboratory overall agreement was 92.6%. In study CD-ON-MEDI4736-1108, durvalumab demonstrated clinical activity and durable responses in both PD-L1-high and PD-L1-low/negative subgroups, although objective response rates tended to be higher in the PD-L1-high subgroup than in the PD-L1-low/negative subgroup. Conclusions.--Determination of PD-L1 expression in urothelial carcinoma patients using the Ventana PD-L1 (SP263) assay was precise, highly reproducible, and clinically relevant. doi: 10.5858/arpa.2017-0555-OA, Urothelial carcinoma (UC) may evade immune detection by exploiting inhibitory checkpoint pathways that suppress antitumor T-cell responses, such as programmed death receptor-1 (PD-1, CD279)/programmed death ligand-1 (PD-L1, B7 homolog 1, [...]

A predictive model of tractor driver's eye positions based on the anthropometric parameters and tractor cab layout parameters was established using the statistical approach. To our knowledge, this model is the first published predictive model of tractor drivers' eye positions that takes account of their body dimensions and tractor types. In order to predict the distribution of the drivers' eye positions precisely, the fore-and-aft positions of the driving seat determined by 180 tractor drivers in three different tractors and the relative positions of the eyes to the designated reference points were recorded to quantitatively demonstrate the distribution rule of their eye positions. The multiple linear regression and principal component analysis were adopted to processing the feature parameters of human and tractor, and the prediction effect of the model was assessed according to the proportion of the driver's eye positions from side view those were within the range of the eyellipse model. The experimental result revealed that the centroid positions and principal axis dip angle of the model differed from each other respectively, while the axis lengths were the same. The principal axis dip angle was horizontal or oblique forward-and-upward. And the tractor layout parameters had a significant impact on the centroid coordinate and principal axis dip angle of the model, while the dimension of the model was associated with the anthropometric parameters mainly. The prediction accuracy of the model exceeded 80%. The regression predictive model provides a reference tool for the visual field design of tractor displays and cab layouts. [ABSTRACT FROM AUTHOR]

To solve the problem of lumbar spine injuries of tractor drivers, lumbar support devices were added to the tractor. The purpose of study is to design lumbar supports with different protrusion thicknesses to adjust the load on the operator's lumbar under whole-body vibration. Integrating pressure distribution measurement with subjective assessment, pressure distribution on the contact surface between ten male tractor drivers and the seat under conditions of different lumbar supports and driving speeds and the influence of the presence of lumbar supports and their thickness on the subjects' comfort were analyzed. The results demonstrated that there existed a certain correlation between the pressure distribution indexes and the drivers' subjective evaluation, and the pressure distribution indexes could reflect ride comfort objectively. The 3 cm thick lumbar support did not improve ride comfort significantly, while the 9 cm thick support exerted too much stress on the waist, causing the lumbar spine to lean forward excessively and aggravating lumbar fatigue. Most subjects in the study would prefer to increase the thickness of the lumbar supports to approximately 6 cm. Based on the pressure distribution test, this study conducted an analysis of the influence of lumbar supports in tractors, which could provide a reference design for tractor seats. [ABSTRACT FROM AUTHOR]

Aims: Diabetic cardiomyopathy (DCM) is an ill-defined entity. This study aims to explore the clinical characteristics and prognosis of diabetic patients that disparately develop heart failure (HF) with preserved ejection fraction (HFpEF) other than HF with reduced ejection fraction (HFrEF). Patients and Methods: A total of 911 patients diagnosed with diabetes mellitus were identified in the ChiHFpEF cohort (NCT05278026). DCM was defined as diabetic patients diagnosed with HF, absent from flow obstructive coronary artery disease (CAD), uncontrolled refractory hypertension and hemodynamics significant heart valvular diseases, arrhythmia and congenital heart diseases. The primary endpoint was a composite of all-cause death and rehospitalization due to HF. Results: As compared to DCM-HFrEF patients, DCM-HFpEF patients had a longer duration of diabetes, were older and more noticeable in hypertension and non-obstructive CAD. After a median follow-up of 45.5 months, survival analysis showed that DCM-HFpEF patients had a better composite endpoint. Cox regression implicated that non-obstructive CAD was a negative (HR 0.101, 95% CI 0.028–0.373, p = 0.001) predictor for the composite endpoint of DCM-HFrEF patients. Age was a positive predictor for the composite endpoint of DCM-HFpEF patients (HR 1.044, 95% CI 1.007–1.082, p = 0.018). Conclusion: DCM-HFpEF is a disparate entity from DCM-HFrEF. Additional phenomic studies are needed to explore the molecular mechanisms and develop targeted therapies. [ABSTRACT FROM AUTHOR]

Due to its excellent insulation properties and environmental characteristics, C6F12O gas mixture shows a wide range of applications prospects in low and medium voltage gas insulated equipment. The thermal decomposition characteristics of gas insulating medium are of great importance for the industrial application of gases and the operation and maintenance of equipment. In this paper, the type and concentration of the main products of the thermal decomposition of C6F12O/O2/CO2 gas mixture are researched experimentally with different O2 mixing ratios, and the effective gas production rate is analyzed. The mechanism of thermal decomposition of C6F12O/O2/CO2 gas mixture is studied based on ReaxFF molecular dynamics. The experimental results show that the main thermal decomposition products are CF4, C2F6, C3F6, C3F8, C4F10, C5F12, and C6F14. The addition of O2 promotes the thermal decomposition of the C6F12O/O2/CO2 gas mixture. Theoretical studies show that the C6F12O in the mixture undergoes the multistage decomposition reaction. The main particles of all levels of decomposition are C3F7COCF2, CF3, CF3CFC(O) (CF2), CF2CO, C3F7, C3F7C(O) (CF2), CFC(O) (CF2), FCCO, F, CF3CFCF2, CO, and CF2. The results of the research can provide some reference for the engineering application and maintenance of C6F12O gas mixture insulated equipment. [ABSTRACT FROM AUTHOR]

Most estimates of US deaths associated with influenza circulation have been similar despite the use of different approaches. However, a recently published estimate suggested that previous estimates substantially overestimated deaths associated with influenza, and concluded that substantial numbers of deaths during a future pandemic could be prevented because of improvements in medical care. We reviewed the data sources and methods used to estimate influenza-associated deaths. We suggest that discrepancies between the recent estimate and previous estimates of the number of influenza-associated deaths are attributable primarily to the use of different outcomes and methods. We also believe that secondary bacterial infections will likely result in substantial morbidity and mortality during a future influenza pandemic, despite medical progress. (Am J Public Health. 2009;99: $225-$230. doi: 10.2105/AJPH.2008.151944)

Differential spatial modulation (DSM) is a multi‐antenna differential technology with low power consumption and no demand of channel estimation. It is suitable for communication systems that have fast migration velocity and high requirements for both power consumption and complexity. However, due to the sparse structure and the requirements of differential coding, the spectral efficiency is limited. Therefore, media‐based modulation (MBM) technology is introduced into differential system in this work to improve the spectral. A differential space time media‐based modulation (DSTMBM) system is proposed. While retaining the inherent advantages of the DSM, the additional bits are transmitted through the radio frequency (RF) mirrors in DSTMBM. Unlike traditional DSM, the transmit antenna of DSTMBM system can be activated multiple times. In addition, a theoretical performance is derived, and a low‐complexity (LC) detection algorithm is adopted. Simulation results show that the DSTMBM system has a performance advantage of about 4.5 dB at a high transmission rate compared to traditional DSM systems. Monte Carlo simulation matches the theoretical performance in a wide range. Meanwhile, the LC detection algorithm reduces the complexity by 2–3 orders of magnitude without the bit error rate (BER) performance loss. [ABSTRACT FROM AUTHOR]

Background. Cold-inducible RNA-binding protein (CIRP) is a proinflammatory cytokine. The Global Registry of Acute Coronary Events (GRACE) risk score has been widely applied in risk stratification in patients with acute coronary syndrome (ACS). We aimed to investigate the prognostic value of CIRP in ACS patients and its incremental prognostic performance on top of GARCE score. Methods. We consecutively enrolled 320 ACS patients, including 128 patients with ST-elevation myocardial infarction (STEMI), 67 patients with non-ST-elevation myocardial infarction (NSTEMI), and 125 patients with unstable angina pectoris (UAP). Plasma CIRP levels were measured at baseline. All patients received one-year follow-up for occurrence of major adverse cardiovascular outcomes (MACEs). Results. STEMI patients had a significantly higher concentration of plasma CIRP than those with NSTEMI (p = 0.001) and UAP (p < 0.001). Plasma CIRP level was positively correlated with GRACE score (r = 0.40 , p < 0.01). Survival analysis revealed that the risk of MACEs increased with increasing CIRP level (log-rank p < 0.001). During follow-up, 45 (14.1%) patients experienced MACEs. Both GRACE score (hazard ratio: 1.023, 95% confidence interval: 1.007-1.050, p = 0.021) and plasma CIRP level (hazard ratio:1.800, 95% confidence interval:1.209-2.679, p = 0.004) were independently predictive of MACEs after Cox multivariate adjustment. Incremental predictive value was observed after combining CIRP with GRACE score. Conclusions. Plasma CIRP was an independent prognostic biomarker and could improve the predictive value of GRACE score for prognosis in ACS patients. [ABSTRACT FROM AUTHOR]

The clinical application of doxorubicin (Dox) is limited due to its cardiotoxicity, while the pathogenesis remains to be fully understood. Recent studies have suggested that microRNA (miRNA) plays an important role in Dox‐induced cardiotoxicity. This work aims to investigate the effects of miR‐125b in Dox‐induced cardiotoxicity. Here, mice model combined with cell line analysis were used, and cell viability assay, detection of reactive oxygen species (ROS), malondialdehyde (MDA) activity, lactate dehydrogenase (LDH) activity, glutathione (GSH) level, glutathione peroxidase (GSH‐Px) level, superoxide dismutase (SOD) activity, and histopathological changes were performed to characterize miR‐125b effects; real‐time quantitative polymerase chain reaction (PCR), luciferase reporter assay, RNA immunoprecipitation, and western blot analysis were subjected to reveal the underlying mechanisms. It was found that miR‐125b level was upregulated in myocardial cell line H9C2 treated with Dox and miR‐125b overexpression enhanced Dox‐induced cytotoxicology of H9C2 cells, while miR‐125b inhibition exhibited a protective effect by measuring ROS level and cell viability. In consistent, in vivo experiments with miR‐125b agomir or antagomir obtained a consistent result through examining the activity of MDA, LDH, GSH, GSH‐Px, SOD, and histopathological changes. Furthermore, we found that miR‐125b could target STARD13 and thus suppressed the nucleus‐cytoplasmic translocation of yes‐associated protein (YAP). Additionally, this STARD13/YAP axis is necessary for miR‐125b‐mediated regulation on Dox‐induced cytotoxicology of H9C2 cells. In conclusion, our study demonstrated that miR‐125b could enhance Dox‐induced cardiotoxicity through targeting the STARD13/YAP axis. [ABSTRACT FROM AUTHOR]

Aiming at improving the accuracy of radar signal recognition under a low signal-to-noise ratio, a radar signal recognition algorithm based both on time-frequency image and high-order spectrum feature was proposed. Firstly, the time-frequency image was obtained by Choi-Williams distribution (CWD) transform, based on which the time-frequency image was preprocessed and the texture features were extracted by gray level co-occurrence matrix (GLCM) in sequence. Meanwhile, the symmetrical holder coefficient was used to extract the high-order spectral features of the signal. Then, the texture features and high-order spectrum features were form a new set of joint feature vectors. Finally, with the proposed feature vector the classification and recognition of radar signals were implemented by a support vector machine. The algorithm was verified on the data set with eight typical radar signals. Experimental results show that the recognition accuracy of different radar signals can achieve higher than 90% when the signal-to-noise ratio is -8 dB. [ABSTRACT FROM AUTHOR]