Cause Of Discrepancy Research Articles

Significant variation in histopathological assessment of endoscopic resections for Barrett's neoplasia suggests need for consensus reporting: propositions for improvement.

Endoscopic resection (ER) is an important diagnostic step in management of patients with early Barrett's esophagus (BE) neoplasia. Based on ER specimens, an accurate histological diagnosis can be made, which guides further treatment. Based on depth of tumor invasion, differentiation grade, lymphovascular invasion, and margin status, the risk of lymph node metastases and local recurrence is judged to be low enough to justify endoscopic management, or high enough to warrant invasive surgical esophagectomy. Adequate assessment of these histological risk factors is therefore of the utmost importance. Aim of this study was to assess pathologist concordance on these histological features on ER specimens and evaluate causes of discrepancy. Of 62 challenging ER cases, one representative H&E slide and matching desmin and endothelial marker were digitalized and independently assessed by 13 dedicated GI pathologists from 8 Dutch BE expert centers, using an online assessment module. For each histological feature, concordance and discordance were calculated. Clinically relevant discordances were observed for all criteria. Grouping depth of invasion categories according to expanded endoscopic treatment criteria (T1a and T1sm1 vs. T1sm2/3), ≥1 pathologist was discrepant in 21% of cases, increasing to 45% when grouping diagnoses according to the traditional T1a versus T1b classification. For differentiation grade, lymphovascular invasion, and margin status, discordances were substantial with 27%, 42%, and 32% of cases having ≥1 discrepant pathologist, respectively. In conclusion, histological assessment of ER specimens of early BE cancer by dedicated GI pathologists shows significant discordances for all relevant histological features. We present propositions to improve definitions of diagnostic criteria.

On the unsteady Reynolds-averaged Navier–Stokes capability of simulating turbulent boundary layers under unsteady adverse pressure gradients

Predictive capabilities of unsteady Reynolds-averaged Navier–Stokes (URANS) techniques using the k−ω shear stress transport and Spalart–Allmaras models are assessed for the simulation of turbulent boundary layers under unsteady adverse pressure gradients by comparing their results with direct numerical simulation (DNS) results. Simulations are conducted for separating and reattaching turbulent boundary layers under periodic adverse pressure gradients. Phase-wise comparisons of the velocity, the Reynolds stress, and the skin friction coefficient obtained by URANS simulations and DNS are carried out. URANS techniques are found to qualitatively well predict the formation of the separation bubble and the phase response of the shear layer height, while they predict earlier separation and a larger recirculation bubble compared with those in DNS. Phase responses of the skin friction predicted by URANS simulations are found not to be an accurate indication of flow separation and reattachment of the turbulent boundary layer. The main causes of discrepancies among DNS and URANS results in the near-wall region are attributed to the different anisotropy of the Reynolds stress, which can be characterized by a barycentric map.

Comparison of tree-ring and eddy-covariance derived annual ecosystem production estimates for jack pine and trembling aspen forests in Saskatchewan, Canada

Reliable projections of future carbon (C) dynamics are essential to resource management decision making under a changing climate. Additional corroborative data may reduce uncertainty in C flux estimates. Here we use a tree-ring based hybrid biometric modelling approach to estimate annual ecosystem production at jack pine (Pinus banksiana) and aspen (Populus tremuloides and Populus balsamifera) plots co-located with eddy-covariance installations in the boreal forest of Saskatchewan, Canada for a 28 year (1985 to 2012) period. Correspondence between tree-ring and eddy-covariance derived estimates was better for jack pine (14-year overlap, 1999 to 2012) than aspen (16-year overlap, 1997 to 2012), and better for some C fluxes than others. In particular, tree-ring estimates of annual and cumulative net ecosystem production were larger than eddy-covariance derived estimates for the overlapping period. Allometric equations, belowground production, and biomass turnover could neither be confirmed nor ruled out as causes of discrepancy, but a lower stand density and higher carbon use efficiency would together reduce observed differences for aspen. Tree-ring based estimates of biomass increment or net primary production showed good temporal correspondences with both current and previous year eddy-covariance analogues, and net and gross primary production. Similar comparisons for net ecosystem production and heterotrophic respiration had mixed results. This study improves on previous work by comparing independent estimates of the same fluxes quantities and demonstrates the value of tree-ring data for evaluating C flux estimates.

Frequency and Significance of Pathologic Pulmonary Findings in Postmortem Examinations-A Single Center Experience before COVID-19.

Coronavirus disease 2019 (COVID-19) has shown the importance of postmortem investigation of deceased patients. For a correct interpretation of the pulmonary findings in this new era, it is, however, crucial to be familiar with pathologic pulmonary conditions observed in postmortem investigations in general. Adequate postmortem histopathological evaluation of the lungs may be affected by suboptimal gross work up, autolysis or poor fixation. Using a standardized preparation approach which consisted in instillation of 4% buffered formaldehyde through the large bronchi for proper fixation and preparing large frontal tissue sections of 1–2 cm thickness after at least 24 h fixation, we comprehensively analyzed postmortem pulmonary findings from consecutive adult autopsies of a two-year period before the occurrence of COVID-19 (2016–2017). In total, significant pathological findings were observed in 97/189 patients (51%), with 28 patients showing more than one pathologic condition. Acute pneumonia was diagnosed 33/128 times (26%), embolism 24 times (19%), primary pulmonary neoplasms 18 times (14%), organizing pneumonia and other fibrosing conditions 14 times (11%), pulmonary metastases 13 times (10%), diffuse alveolar damage 12 times (9%), severe emphysema 9 times (7%) and other pathologies, e.g., amyloidosis 5/128 times (4%). Pulmonary/cardiopulmonary disease was the cause of death in 60 patients (32%). Clinical and pathological diagnoses regarding lung findings correlated completely in 75 patients (40%). Autopsy led to confirmation of a clinically suspected pulmonary diagnosis in 57 patients (39%) and clarification of an unclear clinical lung finding in 16 patients (8%). Major discrepant findings regarding the lungs (N = 31; 16%) comprised cases with clinical suspicions that could not be confirmed or new findings not diagnosed intra vitam. A significant proportion of acute pneumonias (N = 8; 24% of all cases with this diagnosis; p = 0.011) was not diagnosed clinically. We confirmed the frequent occurrence of pulmonary pathologies in autopsies, including inflammatory and neoplastic lesions as the most frequent pathological findings. Acute pneumonia was an important cause for discrepancy between clinical and postmortem diagnostics

Revisiting magnetic field effects in homogeneous medium and bio-mimicking environments with emphasis on acridine derivatives

A weak external magnetic field, very close to the hyperfine interactions of the system, can acts as a tool to monitor spin dynamics and assess distance between the components of the spin-correlated transient radical pair or radical ion pair (RIP). The present review focuses on the magnetic field effect (MFE) on the photo-induced electron-transfer (PET) reactions among acridine derivatives and classical as well as biological electron acceptor or donor moieties, which produce spin-correlated RIPs, in homogeneous solvents, heterogeneous micellar media and in biological nanocavities of proteins. Although a confined medium is preferred to observe prominent MFE, yet unanticipated MFE on PET between acridine derivatives [Acridone (AD) and Acridine Yellow (AY)] and classical electron donors is obtained even in homogeneous medium when it consists of impurities like water molecules. In a comparative study of interaction of another acridine derivative, Proflavin (PF+) with two electron donors which are amines of aromatic nature, MFE on PET reveal that the bulk and the structure of the electron donor govern the mechanism as well as the spin dynamics of PET. While studying interaction of PF+ with a different amine which is aliphatic in nature, MFE on PET implies that it is the nature of the solvent matrix which determines the spin dynamics of PET. The cause of discrepancy in the experimental and calculated values of B1/2 for 9-amino acridine – methyl viologen system has been delineated. Apart from micellar medium, prominent MFE on PET is also observed while studying the interaction of PF+, AY and AD with tryptophan residues present in the nanocavities of serum albumins since the inter-radical distance within primary geminate RIP is enough to make exchange interaction negligible.

GFHT proposals for management of discordance between the International normalized ratio measured in the laboratory and by self-testing

The lack of quality control for patient point-of-care (POC) INR devices is an issue that has led the French health authorities to make recommendations: a laboratory INR (lab INR) has to be performed at the same time as the POC INR every 6 months. However, the differences observed between the two INRs, POC and lab INRs, are not necessarily due to a failure of the POC INR device. We present here a review of the different causes of discrepancies between INR results, which are the basis of the proposals of the Groupe francais d'etudes sur l'hemostase et la thrombose (GFHT) on the management of lab and POC INR discrepancies. Pre-analytical conditions may account for discrepancies (sampling, transport and storage conditions), as well as analytical factors (mainly the nature of the thromboplastin used) and the clinical context (inflammatory or autoimmune diseases, polycythaemia...). The interpretation of INR discrepancies is not always easy and these proposals aim at standardizing the procedure to be followed in order to make the most appropriate decision for the patient.

Teachers’ perspectives on the causes of rater discrepancy in an English for Academic Purposes context

Abstract Many studies have focused on discrepancies in scoring writing, focusing on determining rater types, rubrics and their interpretation, and the factors that make a particular paper hard score. This qualitative study attempts to understand sources of discrepancy from the perspective of the raters themselves. Teachers from an English medium university freshmen academic skills programme provided scores and comments on an exemplar paper with an analytic, three-criteria rubric. Results reveal considerable differences within content and organisation criteria. In the next stage, unstructured interviews were conducted with three teachers from the programme, and their perspectives on rating were compared, and used to interpret possible causes of discrepancies in the first stage. Although the interviewees’ attitudes to the scoring process were broadly similar in terms of accounting for discrepancies, each had a different focus: on institutional factors, teacher role, and the rating process, respectively. The implications for L2 writing standardization are discussed.

High Reynolds number aerodynamic testing of a roof with parapet

Aerodynamic testing was executed on a large-scale building with two distinct aspect ratios (1:6 and 1:3), at a large open-jet facility, Louisiana State University (LSU). To illustrate, a 1:15 scale test model was extensively investigated by experimental testing at a high Reynolds number (~2.3 × 107). The objective was to understand the performance of parapets in reducing the magnitude of localized and area-averaged roof pressures. Through analogy with bare-roof and several parapet configurations, the paper explores the performance of parapet walls and why they can be employed in aerodynamic mitigation. The results suggest installing a parapet wall will act as an aerodynamic mitigation device to reduce negative (uplift) loads. Large-scale testing indicates that the taller the parapet, the higher the reduction in mean and fluctuating pressures. However, depending on the roof’s aspect ratio, there is an optimal parapet height. The study concludes that 40–50% reductions in roof pressures can be achieved with parapets. Along the same lines, to yield high reductions in roof pressures, the parapet height is a key parameter. Short parapets may have low performance under conical vortices. The importance of the current study is that parapets, as well as other architectural features, are widely considered difficult to investigate by small-scale testing, at low Reynolds numbers, the leading cause of discrepancies between the laboratory and field measurements. Consequently, the current paper contributes to knowledge useful to explain the role of parapets in reducing aerodynamic pressures, for buildings to withstand wind loads at high Reynolds numbers.

Dielectric property measurements of corneal tissues for computational dosimetry of the eye in terahertz band in vivo and in vitro.

The dielectric constant of the normal corneal tissue of a rabbit eye was obtained in vitro in the range from approximately 0.1 to 1 THz, and the drying process on the eye surface exposed to high-power terahertz waves was investigated by in vivo reflectance measurement using terahertz time-domain spectroscopy. When the rabbit eye was exposed to terahertz waves at 162 GHz for 6 min with an irradiation power of 360 or 480 mW/cm2, the reflectance temporally increased and then decreased with a temperature increase. Based on multiple-reflection calculation using the dielectric constant and anterior segment optical coherence tomography images, those changes in reflectance were attributed to drying of the tear and epithelium of the cornea, respectively. Furthermore, the drying progressed over a temperature increase of around 5°C under our exposure conditions. These findings suggest that the possibility of eye damage increases with the progress of drying and that the setting of the eye surface conditions can be a cause of disagreement between computational and experimental data of absorbed energy under high-level irradiation because reflectance is related to terahertz wave penetration in the eye tissue. The time-domain spectroscopic measurements were useful for the acquisition of the dielectric constant as well as for the real-time monitoring of the eye conditions during exposure measurement.

Interobserver reproducibility of perineural invasion of prostatic adenocarcinoma in needle biopsies

Numerous studies have shown a correlation between perineural invasion (PNI) in prostate biopsies and outcome. The reporting of PNI varies widely in the literature. While the interobserver variability of prostate cancer grading has been studied extensively, less is known regarding the reproducibility of PNI. A total of 212 biopsy cores from a population-based screening trial were included in this study (106 with and 106 without PNI according to the original pathology reports). The glass slides were scanned and circulated among four pathologists with a special interest in urological pathology for assessment of PNI. Discordant cases were stained by immunohistochemistry for S-100 protein. PNI was diagnosed by all four observers in 34.0% of cases, while 41.5% were considered to be negative for PNI. In 24.5% of cases, there was a disagreement between the observers. The kappa for interobserver variability was 0.67–0.75 (mean 0.73). The observations from one participant were compared with data from the original reports, and a kappa for intraobserver variability of 0.87 was achieved. Based on immunohistochemical findings among discordant cases, 88.6% had PNI while 11.4% did not. The most common diagnostic pitfall was the presence of bundles of stroma or smooth muscle. It was noted in a few cases that collagenous micronodules could be mistaken for a nerve. The distance between cancer and nerve was another cause of disagreement. Although the results suggest that the reproducibility of PNI may be greater than that of prostate cancer grading, there is still a need for improvement and standardization.

Validity of the Polar H7 Heart Rate Sensor for Heart Rate Variability Analysis during Exercise in Different Age, Body Composition and Fitness Level Groups.

This work aims to validate the Polar H7 heart rate (HR) sensor for heart rate variability (HRV) analysis at rest and during various exercise intensities in a cohort of male volunteers with different age, body composition and fitness level. Cluster analysis was carried out to evaluate how these phenotypic characteristics influenced HR and HRV measurements. For this purpose, sixty-seven volunteers performed a test consisting of the following consecutive segments: sitting rest, three submaximal exercise intensities in cycle-ergometer and sitting recovery. The agreement between HRV indices derived from Polar H7 and a simultaneous electrocardiogram (ECG) was assessed using concordance correlation coefficient (CCC). The percentage of subjects not reaching excellent agreement (CCC > 0.90) was higher for high-frequency power (PHF) than for low-frequency power (PLF) of HRV and increased with exercise intensity. A cluster of unfit and not young volunteers with high trunk fat percentage showed the highest error in HRV indices. This study indicates that Polar H7 and ECG were interchangeable at rest. During exercise, HR and PLF showed excellent agreement between devices. However, during the highest exercise intensity, CCC for PHF was lower than 0.90 in as many as 60% of the volunteers. During recovery, HR but not HRV measurements were accurate. As a conclusion, phenotypic differences between subjects can represent one of the causes for disagreement between HR sensors and ECG devices, which should be considered specifically when using Polar H7 and, generally, in the validation of any HR sensor for HRV analysis.

No inexplicable disagreements between real-world data–based nonrandomized controlled studies and randomized controlled trials were found

ObjectivesWe assessed disagreements between nonrandomized controlled studies based on real-world data (NRCS-RWDs) and randomized controlled trials (RCTs). Study Design and SettingWe systematically searched for studies that compared treatment effect estimates from NRCS-RWDs and RCTs on the same clinical question. We assessed the potential difference between NRCS-RWDs and RCTs related to internal and external validity. We calculated various meta-epidemiological measures to assess agreement. In case of disagreements, we tried to identify the probable causes of disagreements. ResultsWe included 12 studies comparing 15 treatment effect estimates of NRCS-RWDs and RCTs. There were many potential causes of disagreement. Ninety-five percent confidence intervals overlapped for 12 of 15 treatment effect estimates. Our analysis on predicted vs. observed overlap showed that there were no more disagreements than expected by chance. We observed only two substantial differences between the 15 treatment effect estimates. In both cases, we identified risk of bias in the NRCS-RWDs as the most probable cause of disagreement. ConclusionOur findings suggest that there are clinical questions where the difference in risk of bias between a well-conducted NRCS-RWD and an RCT is negligible. In our analysis, threats to external validity appeared to have no or only a weak impact on the disagreements of treatment effect estimates.

Hybrid post-Newtonian effective-one-body scheme for spin-precessing compact-binary waveforms up to merger

We introduce \texttt{TEOBResumSP}: an efficient, accurate hybrid scheme for generating gravitational waveforms from spin-precessing compact binaries. The precessing waveforms are generated via the established technique of Euler rotating the non-precessing \texttt{TEOBResumS} waveforms from a precessing frame to an inertial frame. We obtain the Euler angles by solving the post-Newtonian precession equations expanded to second post-Newtonian order. Current version of \texttt{TEOBResumSP} produces precessing waveforms through the inspiral phase up to the onset of the merger. We compare \texttt{TEOBResumSP} to current state-of-the-art precessing approximants \texttt{NRSur7dq4}, \texttt{SEOBNRv4PHM}, and \texttt{IMRPhenomPv3HM} for 200 cases of precessing compact binary inspirals with orbital inclinations up to 90 degrees, mass ratios up to four, and the effective precession parameter $\chi_p$ up to 0.75. We further provide an extended comparison with \texttt{SEOBNRv4PHM} involving 1030 more inspirals with $\chi_p\le 1$ and mass ratios up to 10. We find that 91\% of the \texttt{TEOBResumSP}-\texttt{NRSur7dq4} matches, 85\% of the \texttt{TEOBResumSP}-\texttt{SEOBNRv4PHM} matches, and 77\% of the \texttt{TEOBResumSP}-\texttt{IMRPhenomPv3HM} matches are greater than $0.965$. Most disagreements occur for large mass ratios and $\chi_p \gtrsim 0.6$. We identify the mismatch of the \emph{non}-precessing $(2,1)$ mode as one of the leading causes of disagreements. We also introduce a new parameter, $\chi_{\perp,\text{max}}$, to measure the strength of precession and hint that the mismatch between the above approximants shows an exponential dependence on $\chi_{\perp,\text{max}}$ though this requires further study. Our results indicate that \texttt{TEOBResumSP} is on its way to becoming a robust precessing approximant to be employed in the parameter estimation of generic-spin compact binaries.

THE TCA BENCHMARK FOR VALIDATION OF TEMPERATURE FEEDBACK CALCULATIONS

The TCA benchmark was investigated as a possible candidate for validation of temperature feedback calculations. This benchmark has low-enriched uranium fuel, light water moderation and reflection, and a temperature range of 20–60 °C. The use of three different nuclear data libraries was considered, viz. ENDF/B-VIII.0, JEFF-3.3, and JENDL-4.0. Since the results were not as good as hoped for, additional studies were performed to identify the cause(s) of discrepancies. The benchmark values depend on a choice of delayed neutron data, so it was investigated whether this could be the cause of discrepancies. Also, an assessment was made based on critical configurations only, i.e. avoiding the use of delayed neutron data, whether the calculations exhibit a bias in relation to the benchmark in the results for the effect of temperature. Indications were found that such a bias exists. It is concluded that the choice of delayed neutron data has a significant effect on the benchmark values themselves. The use of three major nuclear data libraries leads to a range of benchmark values for each configuration, rather than one value. Also, one has to take into account the possibility of a bias in the calculation of temperature effects. It is not clear at this point what the cause of the bias is.

ПРИЧИНЫ ВОЗНИКНОВЕНИЯ КОНФЛИКТОВ В СТОМАТОЛОГИЧЕСКОЙ ПРАКТИКЕ, ПУТИ ИХ ПРЕДОТВРАЩЕНИЯ И РАЗРЕШЕНИЯ

Significance: the number of conflicts related to realization of the right to health and medical care especially in such specific branch of medicine as dentistry has recently been on the rise in Russia. Furthermore, among the main fields of social interaction, a large number of interpersonal conflicts does relate to professional activity. Subject of research: conflicts and conflict situations in dental practice. Purpose of work: to identify main groups of causes of conflict situations and conflicts in dental practice and suggest ways to prevent and resolve them. Material and methods: questionnaire survey of dentists with additional interview of the respondents, mathematical and statistical data analysis using the SPSS Statistics software (Pearson chi-square tests, Kruskal-Wallis tests). Results: The majority of the respondents (59.0%) say that they have never had any conflicts with the administration. The leading cause of disagreement is dissatisfaction with the material base and supplies (35%). The prevailing share of the dentists (61.5%) indicate that conflicts between them and a colleague / nurse have never occurred. The main cause of the conflict communication is insubordination or lack of subordination, especially in rural areas and public facilities. Doctors of public healthcare facilities and dentists working in rural areas were more often in conflict with a colleague or manager. Almost all health workers (98%) note that they have encountered conflict patients. The main cause of the conflict communication is long waiting for a dental appointment (33.3%). Out of all factors influencing the relationship, about half of the respondents (53.0%) mentioned the emotional state of the patient. Out of all behavior strategies in conflicts, the majority of dentists (44%) prefer cooperation. Conclusion: Almost all (98%) dentists came into conflict with the patient. The main causes of these conflicts included: long waiting times for admission (33.3%), irrational work of the registry, the administrator (23.1%) and complaints about the quality of services (22.2%). Medical workers with average work experience (10-29 years) were more likely to conflict with the patient about claims to the quality of treatment (31.3%).

ON APPLICATION OF TAPER WINDOWS FOR SIDELOBE SUPPRESSION IN LFM PULSE COMPRESSION

The output signal of the LFM pulse compression filter is analyzed in order to look into causes of discrepancy between the sidelobe level obtainable using standard taper windows with the literature-reported data. The case of applying window functions in the form of cosine harmonics of the Fourier series, which describes a rather great number of the standard windows, is analyzed in detail. Analytical expressions are presented for the output signal of the chirp-pulse compression filter with such windows and for the amount of loss in the signal-to-noise ratio (SNR). Coefficients of window functions containing 2 cosine harmonics of the Fourier series have empirically been selected that made it possible to improve sidelobe suppression by approximately 0.34 dB for B = 21 and more than by 1 dB for B = 7 as compared with the Hamming window. The obtained results allow concluding that the optimization problem for the window function parameters in the case of small pulse duration-bandwidth products should be solved individually for each specific value of B.

GFHT proposals for management of discordance between the International normalized ratio measured in the laboratory and by self-testing

The lack of quality control for patient point-of-care (POC) INR devices is an issue that has led the French health authorities to make recommendations: a laboratory INR (lab INR) has to be performed at the same time as the POC INR every 6 months. However, the differences observed between the two INRs, POC and lab INRs, are not necessarily due to a failure of the POC INR device. We present here a review of the different causes of discrepancies between INR results, which are the basis of the proposals of the Groupe français d'études sur l'hémostase et la thrombose (GFHT) on the management of lab and POC INR discrepancies. Pre-analytical conditions may account for discrepancies (sampling, transport and storage conditions), as well as analytical factors (mainly the nature of the thromboplastin used) and the clinical context (inflammatory or autoimmune diseases, polycythaemia...). The interpretation of INR discrepancies is not always easy and these proposals aim at standardizing the procedure to be followed in order to make the most appropriate decision for the patient.

Discrepancy between Admission and Discharge Diagnoses in Central Serbia: Analysis by the Groups of International Classification of Diseases, 10th Revision.

Background:Repeated research while using the same methodology can be useful and it can enable relevant conclusions in the same health care system. The aim of our study was to perform comparative analysis of the agreement between admission and discharge diagnostic groups in period 2014–2017 with period 2006–2013 in the Clinical Center of Kragujevac, Serbia.Methods:The 5% simple, random sample was made from the basic set of all hospital reports from Clinical Centre Kragujevac, Serbia, in the period 01.01. 2014 – 31.12. 2017 (n=10228). The first four digits of ICD-10 codes at admission and discharge were compared for agreement. We used discharge diagnosis as a “golden standard”. Statistical analysis was performed using Cohen’s Kappa statistic.Results:In the period 2014–2017, agreement between diagnosis among the most ICD10 groups increased in comparison with the period 2006–2013. Disagreements between diagnosis in the period 2014–2017 in comparation with period 2006–2013 was associated with increased length of stay in the hospital (7.5 vs. 9.1 days, P<0.01), patients were younger (54 vs 49.6 yr, P<0.01), number of males declined (26.3% vs 16.2%, P<0.05), kappa value decreased in XV ICD10 group and XI ICD10 group and kappa value increased in XIV ICD10 group.Conclusion:Agreement between admission and discharge diagnosis among the most ICD10 diagnostic groups increased. Introduction of a new web application has increased the quality of data, but interpreting it requires the skill of researchers. Further research should identify modifiable causes of discrepancy between admission and discharge diagnoses.

Liquid Jet Fuel Property Impacts on Combustion Performance

This paper investigates the influence of liquid jet fuel properties on flame lean blowout (LBO) using an annular coflow spray burner. This behavior has been studied before; however, inconsistent conclusions have been reached regarding the dependency of LBO performance on the properties that influence fuel atomization and mixture formation. LBO limits are measured at three different fuel flow rates to evaluate the influence of the atomization quality/regimes on LBO. It was found that the laboratory spray burner provides similar trends in LBO as a realistic gas turbine combustor but with less time and fuel consumption. Furthermore, the approach used in this work differs from traditional LBO measurements in that the fuel flow rate is kept constant while altering the air flow rate to allow for greater control of the atomization process, which is strongly affected by the fuel flow rate. The results suggest that, to an extent, higher amounts of liquid fuel entering the flame can enhance flame stability. They also suggest that testing at different fuel flow conditions and/or with variable injection hardware, coupled with testing of jet fuels exhibiting variations in key physical properties important in their atomization, is most likely the cause of discrepancy observed in previous works.

Parental Care in the Climbing Perch (Anabas testudineus): Confusion or Lost Data?

Anabantoid fishes comprise a unique group, most of whose representatives are characterized by diverse forms of parental care. Evolutional reconstruction of the reproductive strategies of anabantoids is challenging, partly due to the lack of reliable evidence of parental care in a number of its representatives, the most famous of which is the climbing perch. Moreover, apparent contradictions between literary sources frequently occur on the subject. This brief overview attempts to analyze the situation and identify the possible causes of disagreement. The further development in understanding the phylogeny of life history strategies in the group, as well as the concept of evolutionary transitions among parental care patterns in fishes in general, depend on the clarification of this situation.