Synthesis and characterization of CuO@S-doped g-C3N4 based nanocomposites for binder-free sensor applications

This study presents the simultaneous exfoliation and modification of heterostructured copper oxide incorporated sulfur doped graphitic carbon nitride (CuO@S-doped g-C₃N₄) nanocomposites (NCs) synthesized via chemical precipitation and pyrolysis techniques. The results revealed that the approach is feasible and highly efficient in producing 2-dimensional CuO@S-doped g-C₃N₄ NCs. The findings also showed a promising technique for enhancing the optical and electrical properties of bulk g-C₃N₄ by combining CuO nanoparticles (NPs) with S-doped g-C₃N₄. The crystallite and the average size of the NCs were validated using X-ray diffraction (XRD) studies. Incorporation of the cubical structured CuO on flower shaped S-doped-g-C₃N₄ was visualized and characterized through XRD, HR-SEM/EDS/SED, FT-IR, BET, UV-Vis/DRS, PL, XPS and impedance spectroscopy. The agglomerated NCs had various pore sizes, shapes and nanosized crystals, while being photo-active in the UV-vis range. The synergistic effect of CuO and S-doped g-C₃N₄ as co-modifiers greatly facilitates the electron transfer process between the electrolyte and the bare glassy carbon electrode. Specific surface areas of the NCs clearly revealed modification of bulk S-doped g-C₃N₄ when CuO NPs are incorporated with S-doped g-C₃N₄, providing a suitable environment for the binder-free decorated electrode with sensing behavior for hazardous pollutants. This was tested for the preparation of a 4-nitrophenol sensor.

This study presents the simultaneous exfoliation and modification of heterostructured copper oxide incorporated sulfur doped graphitic carbon nitride (CuO@S-doped g-C₃N₄) nanocomposites synthesized via chemical precipitation and pyrolysis techniques.     

Evaluation of the performance of KOMPSAT-3 stereo images in terms of positioning and the generation of digital surface models

KOMPSAT-3 is an optical high-resolution earth observation satellite launched on 19 May 2012. It provides panchromatic optical images at a nominal ground sampling distance (GSD) of 70 cm. This letter provides geometric accuracy evaluation of KOMPSAT-3 stereo images, including position determination and automated digital surface model (DSM) generation. Bias-compensated KOMPSAT-3 stereo achieved positioning accuracy of 0.65 m and 0.70 m in horizontal and vertical directions, respectively. Bias-compensated KOMPSAT-3 images were utilized for automated DSM generation. A DSM showed height errors of about 3.8 m (RMS) when all grids were compared with reference LIDAR data. Geometric performance of KOMPSAT-3 images was also compared with that of WorldView-1 images whose nominal GSD is 46 cm, over the same test area. The positioning accuracy and the accuracy of DSM generation from KOMPSAT-3 were slightly inferior to those of WorldView-1. However, overall performance of the two satellite images was comparable, when the difference of GSD is taken into account.     

心血管三维运动场的重建方法及验证

目的利用近似垂直角度的造影图像序列重建冠状动脉血管的运动场,获得对心血管运动的定量估计。方法在获得两个角度序列中各时刻血管骨架点的二维运动向量的基础上,根据造影系统的透视投影模型和几何变换关系分别反算出三维运动向量两个端点的空间坐标,得到对血管骨架三维形态和运动的描述。结果采用运动场已知的模拟图像验证二维运动估计算法,误差在一个像素左右;采用血管模型图像验证三维重建算法,反投影的均方根误差小于1.5个像素;最后采用临床采集的图像序列进行实验。结论通过对算法的误差进行定性分析和定量估计,证明该方法是可行的,可辅助冠心病的临床诊断。     

Radiometric Method for Determining the Susceptibility of Yeasts to 5-Fluorocytosine

A rapid method for determining the susceptibility of yeasts to 5-fluorocytosine by using the Bactec radiometric system is described.     

Austrian validation and customization of the SAPS 3 Admission Score

Objective  To test the prognostic performance of the SAPS 3 Admission Score in a regional cohort and to empirically test the need and feasibility of regional customization. Design  Prospective multicenter cohort study. Patients and setting  Data on a total of 2,060 patients consecutively admitted to 22 intensive care units in Austria from October 2, 2006 to February 28, 2007. Measurements and results  The database includes basic variables, SAPS 3, length-of-stay and outcome data. The original SAPS 3 Admission Score overestimated hospital mortality in Austrian intensive care patients through all strata of the severity-of-illness. This was true for both available equations, the General and the Central and Western Europe equation. For this reason a customized country-specific model was developed, using cross-validation techniques. This model showed excellent calibration and discrimination in the whole cohort (Hosmer–Lemeshow goodness-of-fit: Ĥ = 4.50, P = 0.922; Ĉ = 5.61, P = 0.847, aROC, 0.82) as well as in the various tested subgroups. Conclusions  The SAPS 3 Admission Score’s general equation can be seen as a framework for addressing the problem of outcome prediction in the general population of adult ICU patients. For benchmarking purposes, region-specific or country-specific equations seem to be necessary in order to compare ICUs on a similar level. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Philipp G. H. Metnitz, Rui Moreno, Peter Bauer, Barbara Metnitz and Jean-Roger Le Gall are all authors of the main SAPS 3 report [4, 5].     

French translation and validation of 3 functional disability scales for neck pain

OBJECTIVE: To translate and assess the reliability and the construct validity of 3 functional disability scales for neck pain. DESIGN: Reliability and validity study. SETTING: Tertiary care teaching hospital and outpatient clinic. PARTICIPANTS: One hundred one patients (mean age, 49 y). INTERVENTION: French translations were obtained by using the "translation-backward translation" method. Adaptations were made after a pilot study. MAIN OUTCOME MEASURES: Impairment outcome measures (visual analog scale [VAS] pain, neck range of motion, morning stiffness, score of neck sensitivity, radiologic score of Kellgren) and patients' perceived handicap (VAS) were recorded at the baseline visit. Three functional disability scales (Neck Disability Index [NDI], Neck Pain and Disability Scale [NPDS], Northwick Park Neck Pain Questionnaire [NPQ]) were recorded twice, at baseline visit and 24 hours later. Reliability was assessed by using the intraclass correlation coefficient (ICC) and the Bland and Altman method. Construct (convergent and divergent) validity was investigated by using the Spearman rank correlation coefficient and a factor analysis was performed. RESULTS: Test-retest was excellent for the NPDS and NDI (ICC =.91,.93, respectively) and good for the NPQ (ICC =.84). The Bland and Altman method showed no systematic trend. Expected convergent and divergent validity were observed only for the NPDS; 3 main factors were extracted by factor analysis and explained 78% of the cumulative variance. CONCLUSION: The 3 translated scales are valid, but the NPDS seems to have the best construct validity.     

X-ray and optical stereo-based 3D sensor fusion system for image-guided neurosurgery

Purpose

In neurosurgery, an image-guided operation is performed to confirm that the surgical instruments reach the exact lesion position. Among the multiple imaging modalities, an X-ray fluoroscope mounted on C- or O-arm is widely used for monitoring the position of surgical instruments and the target position of the patient. However, frequently used fluoroscopy can result in relatively high radiation doses, particularly for complex interventional procedures. The proposed system can reduce radiation exposure and provide the accurate three-dimensional (3D) position information of surgical instruments and the target position.

Methods

X-ray and optical stereo vision systems have been proposed for the C- or O-arm. Two subsystems have same optical axis and are calibrated simultaneously. This provides easy augmentation of the camera image and the X-ray image. Further, the 3D measurement of both systems can be defined in a common coordinate space.

Results

The proposed dual stereoscopic imaging system is designed and implemented for mounting on an O-arm. The calibration error of the 3D coordinates of the optical stereo and X-ray stereo is within 0.1 mm in terms of the mean and the standard deviation. Further, image augmentation with the camera image and the X-ray image using an artificial skull phantom is achieved.

Conclusion

As the developed dual stereoscopic imaging system provides 3D coordinates of the point of interest in both optical images and fluoroscopic images, it can be used by surgeons to confirm the position of surgical instruments in a 3D space with minimum radiation exposure and to verify whether the instruments reach the surgical target observed in fluoroscopic images.

     

Translation and validation of the movement imagery questionnaire-3 second French version

IntroductionMotor imagery (MI) can be defined as the mental simulation of an action without performing it. Its effectiveness can be substantially influenced by imagery ability, and it is currently accepted that three main modalities are used in MI (kinaesthetic imagery, and internal or external visual imageries). In the context of rehabilitation, MI combined with physical therapy is further known to facilitate functional improvements, and promote cortical reorganization and long-term recovery. This study aimed to test the reproducibility and the validity of constructs (internal consistency and factorial structure) of the Movement Imagery Questionnaire-3 Second French version (MIQ-3S^f).MethodThe internal consistency as well as the validity of constructs and the test-retest inter-rate reproducibility of the MIQ-3S^f was examined, in 553 participants, for the kinaesthetic and visual items.ResultsThe composite reliability scores (≥0.92) and the intraclass correlation coefficients (>0.88) for the kinaesthetic, internal visual and external visual imagery subscales revealed satisfactory internal consistency and reproducibility. Moreover, Pearson correlations revealed a strong relationship between the MIQ-3S^f and the MIQ-3^f.Conclusions/Implications. The MIQ-3S^f can be considered as a valid, reliable and useful questionnaire for examining MI ability in the context of rehabilitation.     

Functional characterization and target validation of alternative complex I of Plasmodium falciparum mitochondria

This study reports on the first characterization of the alternative NADH:dehydrogenase (also known as alternative complex I or type II NADH:dehydrogenase) of the human malaria parasite Plasmodium falciparum, known as PfNDH2. PfNDH2 was shown to actively oxidize NADH in the presence of quinone electron acceptors CoQ(1) and decylubiquinone with an apparent K(m) for NADH of approximately 17 and 5 muM, respectively. The inhibitory profile of PfNDH2 revealed that the enzyme activity was insensitive to rotenone, consistent with recent genomic data indicating the absence of the canonical NADH:dehydrogenase enzyme. PfNDH2 activity was sensitive to diphenylene iodonium chloride and diphenyl iodonium chloride, known inhibitors of alternative NADH:dehydrogenases. Spatiotemporal confocal imaging of parasite mitochondria revealed that loss of PfNDH2 function provoked a collapse of mitochondrial transmembrane potential (Psi(m)), leading to parasite death. As with other alternative NADH:dehydrogenases, PfNDH2 lacks transmembrane domains in its protein structure, and therefore, it is proposed that this enzyme is not directly involved in mitochondrial transmembrane proton pumping. Rather, the enzyme provides reducing equivalents for downstream proton-pumping enzyme complexes. As inhibition of PfNDH2 leads to a depolarization of mitochondrial Psi(m), this enzyme is likely to be a critical component of the electron transport chain (ETC). This notion is further supported by proof-of-concept experiments revealing that targeting the ETC's Q-cycle by inhibition of both PfNDH2 and the bc(1) complex is highly synergistic. The potential of targeting PfNDH2 as a chemotherapeutic strategy for drug development is discussed.     

Radiometric prescreen for antitumor activity with Saccharomyces cerevisiae mutant strain.

After modification, a technique for radiometrically measuring bacterial growth has been applied to a mutant strain of Saccharomyces cerevisiae. The assay is based on inhibition of 14CO2 release from [14C]glucose, which provides an extremely sensitive measure of cellular respiratory activity and growth. The criterion for antitumor activity is the differential inhibition of wild-type and mutant (distorted cell membrane) strains of the yeast. The system was optimized for medium, time of incubation, temperature, and size of inoculum. Known antitumor agents, including bleomycin, actinomycin D, adriamycin, and ellipticine were tested in the system, and differential inhibition was observed. Vincristine showed no inhibitory effects at the concentrations tried. The sensitivity for 20% inhibition ranged from 0.8 micrograms of adriamycin per ml to 0.14 mg of ellipticine per ml. Antifungal agents such as amphotericin B exhibited no differential inhibition. Antibacterial agents were inactive. This method may provide a rapid, sensitive, in vitro quantitative assay for antitumor agents which could be applied to a variety of assay needs and which can be run with facilities and equipment available in most laboratories.     

The current status of clinical proteomics and the use of MRM and MRM(3) for biomarker validation

The transfer of biomarkers from the discovery field to clinical use is still, despite progress, on a road filled with pitfalls. Since the emergence of proteomics, thousands of putative biomarkers have been published, often with overlapping diagnostic capacities. The strengthening of the robustness of discovery technologies, particularly in mass spectrometry, has been followed by intense discussions on establishing well-defined evaluation procedures for the identified targets to ultimately allow the clinical validation and then the clinical use of some of these biomarkers. Some of the obstacles to the evaluation process have been the lack of the availability of quick and easy-to-develop, easy-to-use, robust, specific and sensitive alternative quantitative methods when immunoaffinity-based tests are unavailable. Multiple reaction monitoring (MRM; also called selected reaction monitoring) is currently proving its capabilities as a complementary or alternative technique to ELISA for large biomarker panel evaluation. Here, we present how MRM(3) can overcome the lack of specificity and sensitivity often encountered by MRM when tracking minor proteins diluted by complex biological matrices.     

The validation of volumetric real-time 3-dimensional echocardiography for the determination of left ventricular function.

The objective of this study was to validate a real-time 3-dimensional echocardiography (3DE) technique for the determination of left ventricular (LV) volume and ejection fraction (EF). In 10 mongrel dogs, an electromagnetic flow (EMF) probe was placed on the aorta, and the thorax was closed. Transthoracic imaging was performed during multiple hemodynamic conditions (n = 58) with simultaneous measurement of stroke volume (SV) with the use of EMF. From the volumetric data set, LV volumes were manually traced off-line by 2 independent observers with an apical rotation method (6 planes) and a conventional method (biplane) in a subset of conditions. This tracing technique was also evaluated in 18 human subjects in whom the calculated EF values were compared with values derived by multigated radionuclide angiography (MUGA). Excellent correlation and close limits of agreement were noted between SV measured by 3DE and EMF (r = 0.93) in dogs. In comparison with EMF-derived SV, 3DE provided better correlation than the biplane method (r = 0.93 versus r = 0.61). Interobserver and intraobserver variabilities were comparable (r = 0.94 and r = 0.94, respectively). In a comparison of MUGA-derived EF values and those obtained by 3DE in human subjects, 3DE provided better correlation than the biplane method (r = 0.94 versus r = 0.85). Real-time 3DE accurately measures left ventricular volumes transthoracically over a wide range of hemodynamic conditions in dogs and accurately determines EF in humans.     

Direct validation of NGcGM3 ganglioside as a new target for cancer immunotherapy

Objective: The target concept means not only an aberrant expression of a particular molecule in tumour tissues but also evidence of a clear therapeutic advantage, as a consequence of immune-intervention, in an antigen-positive relevant tumour model. Since we reported the presence of NGcGM3 ganglioside in human breast tumours years ago and though Phase I clinical trials of a ganglioside containing vaccine have been conducted, a definitive direct validation of this peculiar molecule as target for cancer immunotherapy has remained unperformed. Methods: Two animal models were used: leghorn chickens and C57BL/6 mice. The murine 3LL-D122 cell line, the derived subcutaneous tumours and metastatic lung lesions were processed for gangliosides identification. Active immunotherapy experiments in the 3LL-D122 spontaneous lung metastasis model were performed with NGcGM3/VSSP vaccine prepared by conjugation of NGcGM3 with the outer membrane proteins of Neisseria meningitides. Results: The 3LL-D122 Lewis lung carcinoma results were consistent with an increased expression of NGcGM3 from primary tumours to metastatic lesions, as observed in human breast cancer samples. Both vaccines, prepared with synthetic or natural-source-derived ganglioside, showed similar anti-tumour and immunogenicity profiles. Finally, a clear involvement of NK1.1⁺ cells and CD8⁺ T cells in the anti-metastatic effect elicited by the vaccine was manifested. Conclusions: While ‘proof of concept’ Phase II and III clinical trials with the NGcGM3/VSSP vaccine in cancer patients are currently ongoing these results reasonably sustain the validation of this peculiar ganglioside as a novel target for cancer immunotherapy.     

Clinical validation of a continuous intravascular neonatal blood gas sensor introduced through an umbilical artery catheter

INTRODUCTION: Arterial blood gas (ABG) values are a necessary diagnostic measurement in the management of critically ill neonates. We hypothesized that a fiberoptic intravascular blood gas sensor, adapted for use through an umbilical artery catheter, would produce blood gas results with clinically acceptable bias and precision, in comparison to laboratory values, but with no blood loss. METHODS: We evaluated a fiberoptic intravascular blood gas sensor (Neotrend) in 23 consecutive neonates suffering respiratory failure. The sensor was inserted into the descending aorta via a 4.0 or 4.5 French umbilical artery catheter and extended 20 mm beyond the catheter tip. Arterial blood samples were drawn as clinically indicated and analyzed using a standard laboratory analyzer. Sensor measurements were recorded at the time of arterial blood sampling. Additionally, we recorded and evaluated data related to umbilical artery catheter placement (low position [L3-L4] vs high position [T8-T10]), duration of sensor functioning and use, and sensor bias and precision compared to the laboratory analyzer (using Bland-Altman technique and linear regression analysis of pH, P(aCO2), and P(aO2)). RESULTS: Duration of sensor use ranged from 1 to 304 hours (3-304 h in high position and 1-91 h in low position). Nine sensors were used for > 72 h (1 in low position and 8 in high position). Nine sensors were placed in low position, with a placement success rate of 56%. Eighteen sensors were placed in high position, with a placement success rate of 89%. The sensor values for pH, P(aCO2), and P(aO2) were strongly correlated (p < 0.0001) with the laboratory-determined values. Bias and precision for all values met standards for discrete analyzers for laboratory use. CONCLUSIONS: The Neotrend device was accurate and reliable in the neonatal setting, allowing blood gas assessment with no iatrogenic blood loss. Catheter placement in high position may increase the likelihood of successful sensor placement and sensor duration of function.     

A study of the feasibility of using KOMPSAT-5 SAR data to map sea ice in the Chukchi Sea in late summer

In this study, a sea ice mapping model based on Random Forest (RF), a rule-based machine learning approach, has been developed for the Korea Multi-Purpose Satellite-5 (KOMPSAT-5) Synthetic Aperture Radar (SAR) data in Enhanced Wide swath mode obtained from 6 August to 9 September 2015 in the Chukchi Sea. A total of 12 texture features derived from backscattering intensity and the gray-level co-occurrence matrix were used as input variables for sea ice mapping. The RF model produced a sea ice map with a grid spacing of 125 m, demonstrating excellent performance in the classification of sea ice and open water with an overall accuracy of 99.2% and a kappa coefficient of 98.5%. Sea ice concentration (SIC) retrieved from the RF-derived sea ice maps was compared with that from ice charts. The mean and median values of the differences between the SICs derived from the RF model and the ice charts were ?8.85% and ?8.38%, respectively. Such difference was attributed to both the uncertainty in the ice charts and classification error of the RF model.     

Exit interview-consultation for research validation and dissemination

Dissemination of research findings to practice and maintenance of rigor and validity in qualitative research are continuing challenges for nurse researchers. Using three nursing home case studies as examples, this article describes how exit interview-consultation was used as (a) a validation strategy and (b) a rapid research dissemination tool that is particularly useful for nursing systems research. Through an exit interview-consultation method, researchers validated inferences made from qualitative and quantitative data collected in three comprehensive nursing home case studies that examined nursing management practices. This exit interview-consultation strategy extends the traditional member-check approach by providing confirmation at the individual and organizational level. The study examined how using the exit interview-consultation strategy can potentially assist nursing home organizations to increase their capacity for improving operations. Benefits from research participation are often indirect; this study's results suggest that exit interview-consultation can provide direct and immediate benefits to organizations and individuals.     

A guide for instrument development and validation

As occupational therapists become increasingly concerned with accountability, the paucity of adequate instrumentation available for documenting therapeutic effectiveness surfaces as a major problem. Therapists will need to construct new or refine existing instruments to satisfy the requirements of third-party payment. The purpose of this paper is to illustrate how a new instrument is planned, developed, and validated. A sequential step-by-step process is illustrated with a flowchart and applied in the hypothetical construction of an attitude scale to assess school administrators' valuing of the role of occupational therapists in the schools. This example is provided to show how general psychometric principles are applied within an occupational therapy context.     

Pre-clinical validation of virtual bronchoscopy using 3D Slicer

Purpose

Lung cancer still represents the leading cause of cancer-related death, and the long-term survival rate remains low. Computed tomography (CT) is currently the most common imaging modality for lung diseases recognition. The purpose of this work was to develop a simple and easily accessible virtual bronchoscopy system to be coupled with a customized electromagnetic (EM) tracking system for navigation in the lung and which requires as little user interaction as possible, while maintaining high usability.

Methods

The proposed method has been implemented as an extension to the open-source platform, 3D Slicer. It creates a virtual reconstruction of the airways starting from CT images for virtual navigation. It provides tools for pre-procedural planning and virtual navigation, and it has been optimized for use in combination with a \(5^{\circ }\) of freedom EM tracking sensor. Performance of the algorithm has been evaluated in ex vivo and in vivo testing.

Results

During ex vivo testing, nine volunteer physicians tested the implemented algorithm to navigate three separate targets placed inside a breathing pig lung model. In general, the system proved easy to use and accurate in replicating the clinical setting and seemed to help choose the correct path without any previous experience or image analysis. Two separate animal studies confirmed technical feasibility and usability of the system.

Conclusions

This work describes an easily accessible virtual bronchoscopy system for navigation in the lung. The system provides the user with a complete set of tools that facilitate navigation towards user-selected regions of interest. Results from ex vivo and in vivo studies showed that the system opens the way for potential future work with virtual navigation for safe and reliable airway disease diagnosis.