Early neoplasia in Barrett's esophagus is difficult to detect and often overlooked during Barrett's surveillance. An automatic detection system could be beneficial, by assisting endoscopists with ...detection of early neoplastic lesions. The aim of this study was to assess the feasibility of a computer system to detect early neoplasia in Barrett's esophagus.
Based on 100 images from 44 patients with Barrett's esophagus, a computer algorithm, which employed specific texture, color filters, and machine learning, was developed for the detection of early neoplastic lesions in Barrett's esophagus. The evaluation by one endoscopist, who extensively imaged and endoscopically removed all early neoplastic lesions and was not blinded to the histological outcome, was considered the gold standard. For external validation, four international experts in Barrett's neoplasia, who were blinded to the pathology results, reviewed all images.
The system identified early neoplastic lesions on a per-image analysis with a sensitivity and specificity of 0.83. At the patient level, the system achieved a sensitivity and specificity of 0.86 and 0.87, respectively. A trade-off between the two performance metrics could be made by varying the percentage of training samples that showed neoplastic tissue.
The automated computer algorithm developed in this study was able to identify early neoplastic lesions with reasonable accuracy, suggesting that automated detection of early neoplasia in Barrett's esophagus is feasible. Further research is required to improve the accuracy of the system and prepare it for real-time operation, before it can be applied in clinical practice.
A platform has been developed to measure the activity of 23 enzymes that are involved in central carbon and nitrogen metabolism in Arabidopsis thaliana. Activities are assayed in optimized stopped ...assays and the product then determined using a suite of enzyme cycling assays. The platform requires inexpensive equipment, is organized in a modular manner to optimize logistics, calculates results automatically, combines high sensitivity with throughput, can be robotized, and has a throughput of three to four activities in 100 samples per person/day. Several of the assays, including those for sucrose phosphate synthase, ADP glucose pyrophosphorylase (AGPase), ferredoxin-dependent glutamate synthase, glycerokinase, and shikimate dehydrogenase, provide large advantages over previous approaches. This platform was used to analyze the diurnal changes of enzyme activities in wild-type Columbia-0 (Col-0) and the starchless plastid phosphoglucomutase (pgm) mutant, and in Col-0 during a prolongation of the night. The changes of enzyme activities were compared with the changes of transcript levels determined with the Affymetrix ATH1 array. Changes of transcript levels typically led to strongly damped changes of enzyme activity. There was no relation between the amplitudes of the diurnal changes of transcript and enzyme activity. The largest diurnal changes in activity were found for AGPase and nitrate reductase. Examination of the data and comparison with the literature indicated that these are mainly because of posttranslational regulation. The changes of enzyme activity are also strongly delayed, with the delay varying from enzyme to enzyme. It is proposed that enzyme activities provide a quasi-stable integration of regulation at several levels and provide useful data for the characterization and diagnosis of different physiological states. As an illustration, a decision tree constructed using data from Col-0 during diurnal changes and a prolonged dark treatment was used to show that, irrespective of the time of harvest during the diurnal cycle, the pgm mutant resembles a wild-type plant that has been exposed to a 3 d prolongation of the night.
The LUX experiment has performed searches for dark-matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. ...Here, for results derived from 1.4×104 kg days of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers’ response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.
To develop evidence-based recommendations for the non-pharmacological management of systemic lupus erythematosus (SLE) and systemic sclerosis (SSc).
A task force comprising 7 rheumatologists, 15 ...other healthcare professionals and 3 patients was established. Following a systematic literature review performed to inform the recommendations, statements were formulated, discussed during online meetings and graded based on risk of bias assessment, level of evidence (LoE) and strength of recommendation (SoR; scale A-D, A comprising consistent LoE 1 studies, D comprising LoE 4 or inconsistent studies), following the European Alliance of Associations for Rheumatology standard operating procedure. Level of agreement (LoA; scale 0-10, 0 denoting complete disagreement, 10 denoting complete agreement) was determined for each statement through online voting.
Four overarching principles and 12 recommendations were developed. These concerned common and disease-specific aspects of non-pharmacological management. SoR ranged from A to D. The mean LoA with the overarching principles and recommendations ranged from 8.4 to 9.7. Briefly, non-pharmacological management of SLE and SSc should be tailored, person-centred and participatory. It is not intended to preclude but rather complement pharmacotherapy. Patients should be offered education and support for physical exercise, smoking cessation and avoidance of cold exposure. Photoprotection and psychosocial interventions are important for SLE patients, while mouth and hand exercises are important in SSc.
The recommendations will guide healthcare professionals and patients towards a holistic and personalised management of SLE and SSc. Research and educational agendas were developed to address needs towards a higher evidence level, enhancement of clinician-patient communication and improved outcomes.
Rate coefficients are directly determined for the reactions of the Criegee intermediates (CI) CH2OO and CH3CHOO with the two simplest carboxylic acids, formic acid (HCOOH) and acetic acid (CH3COOH), ...employing two complementary techniques: multiplexed photoionization mass spectrometry and cavity‐enhanced broadband ultraviolet absorption spectroscopy. The measured rate coefficients are in excess of 1×10−10 cm3 s−1, several orders of magnitude larger than those suggested from many previous alkene ozonolysis experiments and assumed in atmospheric modeling studies. These results suggest that the reaction with carboxylic acids is a substantially more important loss process for CIs than is presently assumed. Implementing these rate coefficients in global atmospheric models shows that reactions between CI and organic acids make a substantial contribution to removal of these acids in terrestrial equatorial areas and in other regions where high CI concentrations occur such as high northern latitudes, and implies that sources of acids in these areas are larger than previously recognized.
Gas‐phase reactions: Direct measurements reveal that rate coefficients for reactions of Criegee intermediates with carboxylic acids are substantially larger than previously assumed. Using these new values, modeling suggests that these reactions can be major sinks both for Criegee intermediates and carboxylic acids in the atmosphere.
Pulsed beams of energetic x-rays and neutrons from intense laser interactions with solid foils are promising for applications where bright, small emission area sources, capable of multi-modal ...delivery are ideal. Possible end users of laser-driven multi-modal sources are those requiring advanced non-destructive inspection techniques in industry sectors of high value commerce such as aerospace, nuclear and advanced manufacturing. We report on experimental work that demonstrates multi-modal operation of high power laser-solid interactions for neutron and x-ray beam generation. Measurements and Monte Carlo radiation transport simulations show that neutron yield is increased by a factor ~2 when a 1 mm copper foil is placed behind a 2 mm lithium foil, compared to using a 2 cm block of lithium only. We explore x-ray generation with a 10 picosecond drive pulse in order to tailor the spectral content for radiography with medium density alloy metals. The impact of using >1 ps pulse duration on laser-accelerated electron beam generation and transport is discussed alongside the optimisation of subsequent bremsstrahlung emission in thin, high atomic number target foils. X-ray spectra are deconvolved from spectrometer measurements and simulation data generated using the GEANT4 Monte Carlo code. We also demonstrate the unique capability of laser-driven x-rays in being able to deliver single pulse high spatial resolution projection imaging of thick metallic objects. Active detector radiographic imaging of industrially relevant sample objects with a 10 ps drive pulse is presented for the first time, demonstrating that features of 200 μm size are resolved when projected at high magnification.
This paper examines how social capital and organizational innovativeness influence business performance through their separate, indirect, or interactive effects, and how these effects differ across ...the institutional contexts of a transition economy and a market economy. In line with institutional theory, our findings show that the effects of social capital are more extensive and probably more malignant in a transition economy than in a market economy. Furthermore, different types of organizational innovativeness, as corporate culture, can be cultivated by different forms of social capital in different institutional contexts. The implications for institutional theory and social capital theory, and the managerial implications, are discussed.
•Definable and unique web structures were identified in the premature biofilms.•The structural backbone of biofilms was built by particles less than 30μm.•Insoluble precipitates of bicarbonate were ...discovered in the dried biomass.•Weaker shear forces at the entrance of labyrinth channel caused more clogging.•Flushing was more effective when the biomass contained lower level of carbohydrate.
Emitter clogging is very common in reclaimed water drip irrigation schemes. The clogging biomass appears due to bio-fouling of the emitters’ flow paths. The fouling biomass is a composite of microbial secretions and suspended particles both of which originate from the reclaimed water. This study investigates the process of bio-fouling in three types of pressure compensated (PC) emitters applying reclaimed water in South Australia. An experimental drip irrigation (DI) system containing subsurface type emitters was built and operated under a specific thermal range (16–24°C). A constant load of suspended solid in the reclaimed water was maintained throughout the experiment. Four ranges of organic particles (up to 300μm) were applied as the suspended load. The study identified series of definable web structures in the matrix of premature biofilms. The majority of the particles that contributed in building the interior of the biofilm were smaller than 30μm. The protein–carbohydrate ratio (>1) in the exo-polymeric substance (EPS) was recommended as a tool to predict the best period for flushing. Weaker hydrodynamic forces were observed in the low flow emitters (<2L/h) which were also very sensitive to clogging. On the contrary, emitters with higher flow rate experienced much stronger shear forces in the system and showed better anti-clogging performances throughout the experiment.
Rationale
How striatal dopamine synthesis capacity (DSC) contributes to the pathogenesis of negative symptoms in first-episode schizophrenia (SZ) and delusional disorder (DD) has seldom been ...explored. As negative symptoms during active psychotic episodes can be complicated by secondary influences, such as positive symptoms, longitudinal investigations may help to clarify the relationship between striatal DSC and negative symptoms and differentiate between primary and secondary negative symptoms.
Objective
A longitudinal study was conducted to examine whether baseline striatal DSC would be related to negative symptoms at 3 months in first-episode SZ and DD patients.
Methods
Twenty-three first-episode age- and gender-matched patients (11 DD and 12 SZ) were consecutively recruited through an early intervention service for psychosis in Hong Kong. Among them, 19 (82.6%) patients (9 DD and 10 SZ) were followed up at 3 months. All patients received an
18
F-DOPA PET/MR scan at baseline.
Results
Baseline striatal DSC (
K
occ;30–60
) was inversely associated with negative symptoms at 3 months in first-episode SZ patients (
r
s
= − 0.80,
p
= 0.010). This association remained in SZ patients even when controlling for baseline negative, positive, and depressive symptoms, as well as cumulative antipsychotic dosage (
β
= − 0.69,
p
= 0.012). Such associations were not observed in first-episode DD patients. Meanwhile, the severity of negative symptoms at 3 months was associated with more positive symptoms in DD patients (
r
s
= 0.74,
p
= 0.010) and not in SZ patients.
Conclusions
These findings highlight the role of striatal DSC in negative symptoms upon resolution of active psychotic episodes among first-episode SZ patients. Baseline striatal dopamine activity may inform future symptom expression with important treatment implications.
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