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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.

BackgroundThe internal rural-to-urban migration is one of the major challenges for tuberculosis (TB) control in China. Patient costs incurred during TB diagnosis and treatment could cause access and adherence barriers, particularly among migrants. Here, we estimated the prevalence of catastrophic costs of TB patients and its associated factors in an urban population with internal migrants in China.MethodsA cross-sectional survey was conducted to enroll culture-confirmed pulmonary TB patients in Songjiang district, Shanghai, between December 1, 2014, and December 31, 2015. Consenting participants completed a questionnaire, which collected direct and indirect costs before and after the diagnosis of TB. The catastrophic cost was defined as the annual expenses of TB care that exceeds 20% of total household disposable income. We used logistic regression to identify factors associated with catastrophic costs.ResultsOverall, 248 drug-susceptible TB patients were enrolled, 70% (174/248) of them were from migrants. Migrant patients were significantly younger compared to resident patients. The total costs were 25,824 ($3689) and 13,816 ($1974) Chinese Yuan (RMB) in average for resident and migrant patients, respectively. The direct medical cost comprised about 70% of the total costs among both migrant and resident patients. Overall, 55% (132 of 248) of patients experienced high expenses (>10% of total household income), and 22% (55 of 248) experienced defined catastrophic costs. The reimbursement for TB care only reduced the prevalence of catastrophic costs to 20% (49 of 248). Meanwhile, 52% (90 of 174) of the internal migrants had no available local health insurance. Hospitalizations, no available insurance, and older age (> 45-year-old) contributed significantly to the occurrence of catastrophic costs.ConclusionsThe catastrophic cost of TB service cannot be overlooked, despite the free policy. Migrants have difficulties benefiting from health insurance in urban cities. Interventions, including expanded medical financial assistance, are needed to secure universal TB care.

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]

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]

PurposeTo investigate the safety and efficacy of durvalumab, a human monoclonal antibody that binds programmed cell death ligand-1 (PD-L1), and the role of PD-L1 expression on clinical response in patients with advanced urothelial bladder cancer (UBC).MethodsA phase 1/2 multicenter, open-label study is being conducted in patients with inoperable or metastatic solid tumors. We report here the results from the UBC expansion cohort. Durvalumab (MEDI4736, 10 mg/kg every 2 weeks) was administered intravenously for up to 12 months. The primary end point was safety, and objective response rate (ORR, confirmed) was a key secondary end point. An exploratory analysis of pretreatment tumor biopsies led to defining PD-L1-positive as ≥ 25% of tumor cells or tumor-infiltrating immune cells expressing membrane PD-L1.ResultsA total of 61 patients (40 PD-L1-positive, 21 PD-L1-negative), 93.4% of whom received one or more prior therapies for advanced disease, were treated (median duration of follow-up, 4.3 months). The most common treatment-related adverse events (AEs) of any grade were fatigue (13.1%), diarrhea (9.8%), and decreased appetite (8.2%). Grade 3 treatment-related AEs occurred in three patients (4.9%); there were no treatment-related grade 4 or 5 AEs. One treatment-related AE (acute kidney injury) resulted in treatment discontinuation. The ORR was 31.0% (95% CI, 17.6 to 47.1) in 42 response-evaluable patients, 46.4% (95% CI, 27.5 to 66.1) in the PD-L1-positive subgroup, and 0% (95% CI, 0.0 to 23.2) in the PD-L1-negative subgroup. Responses are ongoing in 12 of 13 responding patients, with median duration of response not yet reached (range, 4.1+ to 49.3+ weeks).ConclusionDurvalumab demonstrated a manageable safety profile and evidence of meaningful clinical activity in PD-L1-positive patients with UBC, many of whom were heavily pretreated.

* 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, [...]