534 research outputs found
A software testing approach supported by a tool environment for the development of component tests
Applying the Geostatistical Eigenvector Spatial Filter Approach into Regularized Regression for Improving Prediction Accuracy for Mass Appraisal
Prediction accuracy for mass appraisal purposes has evolved substantially over the last few decades, facilitated by the evolution in big data, data availability and open source software. Accompanying these advances, newer forms of geo-spatial approaches and machine learning (ML) algorithms have been shown to help improve house price prediction and mass appraisal assessment. Nonetheless, the adoption a of ML within mass appraisal has been protracted and subject to scrutiny by assessment jurisdictions due to their failure to account for spatial autocorrelation and limited practicality in terms of value significant estimates needed for tribunal defense and explainability. Existing research comparing traditional regression approaches has tended to examine unsupervised ML methods such as Random Forest (RF) models which remain more esoteric and less transparent in producing value significant estimates necessary for mass appraisal explainability and defense. Therefore, the purpose of this study is to apply the supervised Regularized regression technique which offers a more transparent alternative, and integrate this with a more nuanced geo-statistical technique, the Eigenvector Spatial Filter (ESF) approach, to more accurately account for spatial autocorrelation and enhance prediction accuracy whilst improving explainability needed for mass appraisal exercises. By undertaking such an approach, the research demonstrates the application of this method can be easily adopted for property tax jurisdictions in a framework which is more interpretable, transparent and useable within mass appraisal given its simple and appealing approach. The findings reveal that the integration of the ESFs improves model explainability, prediction accuracy and spatial residual error compared to baseline classical regression and Elastic-net regularized regression architectures, whilst offering the necessary ‘front-facing’ and flexible structure for in-sample and out-of-sample assessment needed by the assessment community for valuing the unsold housing stock. In terms of policy and practice, the study demonstrates some important considerations for mass appraisal tax assessment and for the improvement of taxation assessment and the alleviation of horizontal and vertical inequity
Perivascular Epithelioid Cell Tumor of the Retroperitoneum in a Young Woman Resulting in an Abdominal Chyloma
The additional value of an oblique image plane for MRI of the anterior and posterior distal tibiofibular syndesmosis
Objective: The optimal MRI scan planes of collateral ligaments of the ankle have been described extensively, with the exception of the syndesmotic ligaments. We assessed the optimal scan plane for depicting the distal tibiofibular syndesmosis. Materials and Methods: In order to determine the optimal oblique caudal-cranial and lateral-medial MRI scan plane, two fresh frozen cadaveric ankles were used. The angle of the scan plane that demonstrated the anterior and posterior distal tibiofibular ligament uninterrupted in their full length was determined. In a prospective study this oblique scan plane was then used in addition to the axial and coronal planes, for MRI scans of both ankles in 21 healthy volunteers. Two observers independently evaluated the anterior tibiofibular ligament (ATIFL) and posterior tibiofibular ligament (PTIFL) regarding the continuity of the individual fascicles, thickness and wavy contour of the ligaments in both the axial and the oblique plane. Kappa was calculated to determine the interobserver agreement. McNemar's test was used to statistically quantify the significance of the two scan planes. Results: In the axial plane the ATIFL was in 31% (13/42) partly and in 69% (29/42) completely discontinuous; in the oblique plane the ATIFL was continuous in 88% (37/42) and partly discontinuous in 12% (5/42). Compared with the axial plane, the oblique plane demonstrated significantly less discontinuity (p < 0.001), but not significantly less thickening (p = 1.00) or less wavy contour (p = 0.06) of the ATIFL. In the axial scan plane the PTIFL was continuous in 76% (32/42), partially discontinuous in 19% (8/42) and completely discontinuous in 5% (2/42); in the oblique plane the PTIFL was continuous in 100% (42/42). Compared with the axial plane, the oblique plane demonstrated significantly less discontinuity (p = 0.002), but not significantly less thickening (p = 1.00) or less wavy contour (p = 0.50) of the PTIFL. The interobserver agreement score and kappa (κ) regarding the continuity for the ATIFL in the axial and oblique planes was 91% (κ = 0.79) and 91% (κ = 0.55) respectively; for the PTIFL it was 86% (κ = 0.65) and 100% (κ = not defined). Conclusion: The ATIFL and PTIFL are routinuely scanned in the orthogonal planes. The advantage of MRI scanning in an oblique image plane of about 45 degrees permits a better evaluation of the ligaments compared with the axial plane, particularly a better interpretation of ligament continuity, thickening and wavy contour. This may lead to a reduction in false-positive results, especially regarding partial or complete ligament ruptures. This can be of considerable aid in therapeutic management
Improvement in pain-related quality of life in patients with hemophilia A treated with rFVIIIFc individualized prophylaxis: post hoc analysis from the A-LONG study
Background: Pain, a common symptom of hemophilia, begins early in life primarily due to joint bleeding. Recurrent bleeding adversely affects patients’ pain-related physical functioning, which can negatively impact their quality of life (QoL). Objective: Post hoc analysis of data from the A-LONG study (NCT01181128), to assess change over time in pain-related QoL in patients with severe hemophilia A treated prophylactically with recombinant factor VIII Fc fusion protein (rFVIIIFc). Methods: Patients who completed Haem-A-QoL (17–65 years) and EQ-5D-3L (⩾12–65 years) questionnaires at baseline (BL) and end of study (EoS). Individual-level changes were assessed using three pain-related items of the Haem-A-QoL ‘Physical Health’ domain and the pain/discomfort item of EQ-5D-3L. Distributions of responses (EoS versus BL) were compared using McNemar’s test. Results: A significantly greater proportion of patients reported they did not experience painful swellings (n = 87; 66% versus 46%, p < 0.01) or pain in their joints (n = 89; 42% versus 27%; p < 0.05) at EoS versus BL. The proportion of patients who did not find it painful to move numerically increased at EoS versus BL (n = 86; 47% versus 38%; p = NS). A significantly greater proportion of patients reported no pain/discomfort at EoS versus BL (n = 116; 45% versus 34%; p < 0.05). Conclusion: This study reports the effect of FVIII prophylaxis on patient-reported measures of pain over time in patients with severe hemophilia A. The results of this post hoc analysis showed improvements in pain from BL to EoS in patients receiving rFVIIIFc individualized prophylaxis indicating effective pain management, a key component of patient care
Prognosis Does not Change the Landscape: Palliative Home Care Clients Experience High Rates of Pain and Nausea, Regardless of Prognosis
Background: Most individuals who typically receive palliative care (PC) tend to have cancer and a relatively short prognosis (\u3c 6 months). People with other life-limiting illnesses can also benefit from a palliative care approach. However, little is known about those who receive palliative home care in Ontario, Canada\u27s largest province. To address this gap, the goal of this project was to understand the needs, symptoms and potential differences between those with a shorter (\u3c 6 months) and longer prognosis (6+ months) for individuals receiving PC in the community.
Methods: A cross-sectional analysis was conducted using interRAI Palliative Care (interRAI PC) assessment data collected between 2011 and 2018. Individuals with a shorter prognosis (\u3c 6 months; n = 48,019 or 64.1%) were compared to those with a longer prognosis (6+ months; n = 26,945) across several clinical symptoms. The standardized difference (stdiff), between proportions, was calculated to identify statistically meaningful differences between those with a shorter and longer prognosis. Values of the stdiff of 0.2 or higher (absolute value) indicated a statistically significant difference.
Results: Overall, cancer was the most prevalent diagnosis (83.2%). Those with a shorter prognosis were significantly more likely to experience fatigue (75.3% vs. 59.5%; stdiff = 0.34) and shortness of breath at rest (22.1% vs. 13.4%; stdiff = 0.23). However, the two groups were similar in terms of severe pain (73.5% vs. 66.5%; stdiff = - 0.15), depressive symptoms (13.2% vs. 10.7%; stdiff = 0.08) and nausea (35.7% vs. 29.4%; stdiff = 0.13).
Conclusions: These results highlight the importance of earlier identification of individuals who could benefit from a palliative approach to their care as individuals with a longer prognosis also experience high rates of symptoms such as pain and nausea. Providing PC earlier in the illness trajectory has the potential to improve an individual\u27s overall quality of life throughout the duration of their illness
Reversible and tunable second-order nonlinear optical susceptibility in PZT thin films for integrated optics
Second-order nonlinear optical processes enable a wide range of applications used in research and industry. The majority of available second-order nonlinear devices however relies on bulk nonlinear crystals with low second-order nonlinearity. By exploiting the advancements made in integrated optics, materials with large second-order nonlinearity can enable efficient and small-sized on-chip nonlinear devices at low cost. Unfortunately, silicon and silicon nitride, mostly used for photonics integrated circuits exhibit negligible second-order nonlinearity (χ(2)) and alternate materials have to be investigated. Lead zirconate titanate (PZT) thin films with high second-order nonlinearity stand as a good candidate for on-chip nonlinearity. An electric-field induced tuning of χ(2) is demonstrated here in PZT thin films grown on glass substrates with a tuning efficiency of 3.35 pm V−2. Strong second-harmonic generation is recorded and a very high dominant tensor component χzzz(2) of 128 pm V−1 is reported. The χ(2) of the PZT thin films can be reversed by poling with a DC electric field at room temperature. This opens avenues for highly efficient and tunable on-chip nonlinear devices
The prognostic value of the hypoxia markers CA IX and GLUT 1 and the cytokines VEGF and IL 6 in head and neck squamous cell carcinoma treated by radiotherapy ± chemotherapy
BACKGROUND: Several parameters of the tumor microenvironment, such as hypoxia, inflammation and angiogenesis, play a critical role in tumor aggressiveness and treatment response. A major question remains if these markers can be used to stratify patients to certain treatment protocols. The purpose of this study was to investigate the inter-relationship and the prognostic significance of several biological and clinicopathological parameters in patients with head and neck squamous cell carcinoma (HNSCC) treated by radiotherapy ± chemotherapy. METHODS: We used two subgroups of a retrospective series for which CT-determined tumoral perfusion correlated with local control. In the first subgroup (n = 67), immunohistochemistry for carbonic anhydrase IX (CA IX) and glucose transporter-1 (GLUT-1) was performed on the pretreatment tumor biopsy. In the second subgroup (n = 34), enzyme linked immunosorbent assay (ELISA) was used to determine pretreatment levels of the cytokines vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in serum. Correlation was investigated between tumoral perfusion and each of these biological markers, as well as between the markers mutually. The prognostic value of these microenvironmental parameters was also evaluated. RESULTS: For CA IX and GLUT-1, the combined assessment of patients with both markers expressed above the median showed an independent correlation with local control (p = 0.02) and disease-free survival (p = 0.04) with a trend for regional control (p = 0.06). In the second subgroup, IL-6 pretreatment serum level above the median was the only independent predictor of local control (p = 0.009), disease-free survival (p = 0.02) and overall survival (p = 0.005). CONCLUSION: To our knowledge, we are the first to report a link in HNSCC between IL-6 pretreatment serum levels and radioresistance in vivo. This link is supported by the strong prognostic association of pretreatment IL-6 with local control, known to be the most important parameter to judge radiotherapy responses. Furthermore, the combined assessment of CA IX and GLUT-1 correlated independently with prognosis. This is a valuable indication that a combined approach is important in the investigation of prognostic markers
MR-plastination-arthrography: A new technique used to study the distal tibiofibular syndesmosis
Purpose: The purpose of this study was to describe a new technique called MR plastination arthrography to study both intra- and extra-articular anatomy. Materials and methods: In six human cadaveric lower legs MR arthrography was performed in either a one-step or two-step procedure. In the former a mixture of diluted Gadolinium and dyed polymer was injected. In the latter the dyed polymer was injected after arthrography wih diluted Gadolinium. Three-millimeter slices of these legs, obtained in a plane identical to that of the MR images, were plastinated according to the E12 technique of von Hagens. The plastination slices were subsequently compared with the MR images. Results: The one-step procedure resulted in an inhomogeneous arthrogram. The two-step procedure resulted in a good correlation between the high-resolution MR images and plastination slices, as expressed by a good comparison of anatomic detail of the small syndesmotic recess. Conclusions: Images of the distal tibiofibular syndesmosis obtained with plastination arthrography correlated well with images acquired by MR arthrography when performed in a two-step procedure
The interRAI CHESS Scale is Comparable to the Palliative Performance Scale in Predicting 90-day Mortality in a Palliative Home Care Population
Background: Prognostic accuracy is important throughout all stages of the illness trajectory as it has implications for the timing of important conversations and decisions around care. Physicians often tend to over-estimate prognosis and may under-recognize palliative care (PC) needs. It is therefore essential that all relevant stakeholders have as much information available to them as possible when estimating prognosis.
Aims: The current study examined whether the interRAI Changes in Health, End-Stage Disease, Signs and Symptoms (CHESS) Scale is a good predictor of mortality in a known PC population and to see how it compares to the Palliative Performance Scale (PPS) in predicting 90-day mortality.
Methods: This retrospective cohort study used data from 2011 to 2018 on 80,261 unique individuals receiving palliative home care and assessed with both the interRAI Palliative Care instrument and the PPS. Logistic regression models were used to evaluate the relationship between the main outcome, 90-day mortality and were then replicated for a secondary outcome examining the number of nursing visits. Comparison of survival time was examined using Kaplan-Meier survival curves.
Results: The CHESS Scale was an acceptable predictor of 90-day mortality (c-statistic = 0.68; p \u3c 0.0001) and was associated with the number of nursing days (c = 0.61; p \u3c 0.0001) and had comparable performance to the PPS (c = 0.69; p \u3c 0.0001). The CHESS Scale performed slightly better than the PPS in predicting 90-day mortality when combined with other interRAI PC items (c = 0.72; p \u3c 0.0001).
Conclusion: The interRAI CHESS Scale is an additional decision-support tool available to clinicians that can be used alongside the PPS when estimating prognosis. This additional information can assist with the development of care plans, discussions, and referrals to specialist PC teams
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