Reduction of the cardiac pulsation artifact and improvement of lesion conspicuity in flow-compensated diffusion images in the liver-A quantitative evaluation of postprocessing algorithms.

PURPOSE: To enhance image quality of flow-compensated diffusion-weighted liver MRI data by increasing the lesion conspicuity and reducing the cardiac pulsation artifact using postprocessing algorithms. METHODS: Diffusion-weighted image data of 40 patients with liver lesions had been acquired at 1.5 T. These data were postprocessed with 5 different algorithms (weighted averaging, p-mean, percentile, outlier exclusion, and exception set). Four image properties of the postprocessed data were evaluated for optimizing the algorithm parameters. These properties were the lesion to tissue contrast-to-noise ratio (CNR), the reduction of the cardiac pulsation artifact, the data consistency, and the vessel darkness. They were combined into a total quality score ( Q total , $$ {Q}_{\mathrm{total}}, $$ set to 1 for the trace-weighted reference image), which was used to rate the image quality objectively. RESULTS: The weighted averaging algorithm performed best according to the total quality score ( Q total = 1.111 ± 0.067 $$ {Q}_{\mathrm{total}}=1.111\pm 0.067 $$ ). The further ranking was outlier exclusion algorithm ( Q total = 1.086 ± 0.061 $$ {Q}_{\mathrm{total}}=1.086\pm 0.061 $$ ), p-mean algorithm ( Q total = 1.045 ± 0.049 $$ {Q}_{\mathrm{total}}=1.045\pm 0.049 $$ ), percentile algorithm ( Q total = 1.012 ± 0.049 $$ {Q}_{\mathrm{total}}=1.012\pm 0.049 $$ ), and exception set algorithm ( Q total = 0.957 ± 0.027 $$ {Q}_{\mathrm{total}}=0.957\pm 0.027 $$ ). All optimized algorithms except for the exception set algorithm corrected the pulsation artifact and increased the lesion CNR. Changes in Q total $$ {Q}_{\mathrm{total}} $$ were significant for all optimized algorithms except for the percentile algorithm. Liver ADC was significantly reduced (except for the exception set algorithm), particularly in the left lobe. CONCLUSION: Postprocessing algorithms should be used for flow-compensated liver DWI. The proposed weighted averaging algorithm seems to be suited best to increase the image quality of artifact-corrupted flow-compensated diffusion-weighted liver data.

A new isotopic reference material for stable hydrogen and oxygen isotope-ratio measurements of water - USGS50 Lake Kyoga Water.

RATIONALE: As a result of the need for isotopic reference waters having high δ(2) HVSMOW-SLAP and δ(18) OVSMOW-SLAP values for daily use, especially for tropical and equatorial-zone freshwaters, a new secondary isotopic reference material for international distribution was prepared from water collected from Lake Kyoga, Uganda. METHODS: This isotopic reference lakewater was filtered through a membrane with 0.2-µm pore size, homogenized, loaded into glass ampoules that were sealed with a torch and autoclaved to eliminate biological activity, and measured by dual-inlet isotope-ratio mass spectrometry. This reference material is available in a case of 144 glass ampoules each containing 5 mL of water. RESULTS: The δ(2) H and δ(18) O values of this reference material are +32.8 ± 0.4 and +4.95 ± 0.02 mUr (milliurey = 0.001 = 1 ‰), respectively, relative to VSMOW, on scales normalized such that the δ(2) H and δ(18) O values of SLAP reference water are, respectively, -428 and -55.5 mUr. Each uncertainty is an estimated expanded uncertainty (U = 2uc ) about the reference value that provides an interval that has about a 95 % probability of encompassing the true value. CONCLUSIONS: This isotopic reference material, designated as USGS50, is intended as one of two reference waters for daily normalization of stable hydrogen and oxygen isotopic analysis of water with an isotope-ratio mass spectrometer or a laser absorption spectrometer, of use especially for isotope-hydrology laboratories analyzing freshwater samples from equatorial and tropical regions.

Biscayne aquifer drinking water (USGS45): a new isotopic reference material for δ2H and δ18O measurements of water.

RATIONALE: As a result of the scarcity of isotopic reference waters for daily use, a new secondary isotopic reference material for international distribution has been prepared from drinking water collected from the Biscayne aquifer in Ft. Lauderdale, Florida. METHODS: This isotopic reference water was filtered, homogenized, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity, and measured by dual-inlet isotope-ratio mass spectrometry. This reference material is available by the case of 144 glass ampoules containing either 4 mL or 5 mL of water in each ampoule. RESULTS: The δ(2)H and δ(18)O values of this reference material are -10.3 ± 0.4‰ and -2.238 ± 0.011‰, respectively, relative to VSMOW, on scales normalized such that the δ(2)H and δ(18)O values of SLAP reference water are, respectively, -428 and -55.5‰. Each uncertainty is an estimated expanded uncertainty (U = 2uc ) about the reference value that provides an interval that has about a 95% probability of encompassing the true value. CONCLUSIONS: This isotopic reference material, designated as USGS45, is intended as one of two isotopic reference waters for daily normalization of stable hydrogen and oxygen isotopic analysis of water with an isotope-ratio mass spectrometer or a laser absorption spectrometer. Published in 2014. This article is a U.S. Government work and is in the public domain in the USA.

Lake Louise water (USGS47): a new isotopic reference water for stable hydrogen and oxygen isotope measurements.

RATIONALE: Because of the paucity of isotopic reference waters for daily use, a new secondary isotopic reference material has been prepared from Lake Louise water from Alberta, Canada, for international distribution. METHODS: This water was filtered, homogenized, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity, and measured by dual-inlet isotope-ratio mass spectrometry. This isotopic reference water is available by the case of 144 glass ampoules containing 5 mL of water in each ampoule. RESULTS: The δ(2)H and δ(18)O values of this reference water are -150.2 ± 0.5‰ and -19.80 ± 0.02‰, respectively, relative to VSMOW, on scales normalized such that the δ(2)H and δ(18)O values of SLAP reference water are, respectively, -428 and -55.5‰. Each uncertainty is an estimated expanded uncertainty (U = 2uc) about the reference value that provides an interval that has about a 95% probability of encompassing the true value. CONCLUSIONS: This isotopic reference material, designated as USGS47, is intended as one of two isotopic reference waters for daily normalization of stable hydrogen and stable oxygen isotopic analysis of water with a mass spectrometer or a laser absorption spectrometer. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

Feature-guided deep learning reduces signal loss and increases lesion CNR in diffusion-weighted imaging of the liver.

PURPOSE: This research aims to develop a feature-guided deep learning approach and compare it with an optimized conventional post-processing algorithm in order to enhance the image quality of diffusion-weighted liver images and, in particular, to reduce the pulsation-induced signal loss occurring predominantly in the left liver lobe. METHODS: Data from 40 patients with liver lesions were used. For the conventional approach, the best-suited out of five examined algorithms was chosen. For the deep learning approach, a U-Net was trained. Instead of learning "gold-standard" target images, the network was trained to optimize four image features (lesion CNR, vessel darkness, data consistency, and pulsation artifact reduction), which could be assessed quantitatively using manually drawn ROIs. A quality score was calculated from these four features. As an additional quality assessment, three radiologists rated different features of the resulting images. RESULTS: The conventional approach could substantially increase the lesion CNR and reduce the pulsation-induced signal loss. However, the vessel darkness was reduced. The deep learning approach increased the lesion CNR and reduced the signal loss to a slightly lower extent, but it could additionally increase the vessel darkness. According to the image quality score, the quality of the deep-learning images was higher than that of the images obtained using the conventional approach. The radiologist ratings were mostly consistent with the quantitative scores, but the overall quality ratings differed among the readers. CONCLUSION: Unlike the conventional algorithm, the deep-learning algorithm increased the vessel darkness. Therefore, it may be a viable alternative to conventional algorithms.

[Expected education deficiencies from Covid-related school-lockdowns in spring 2020-empirical evidence on family-education resources using nonlinear regression]. / Erwartete Schulprobleme als Folge der Corona-Schulschließungen im Frühjahr 2020 ­ Empirische Evidenz zur Bedeutung familialer Ressourcen mittels nichtlinearer Modellierung.

In light of the Covid-19-related school lockdowns in Germany in 2020 schools, families and the students were faced with the major challenge to continue instruction at home. This paper examines the expectations of the parents that their children will experience school-related problems as a result to the lockdown-induced homeschooling within the next six months. For our explorative analysis, we choose a nonlinear regression approach. In the course of this, we introduce nonlinear models and highlight their added value compared to methods commonly used in empirical educational research. For the analysis we combine data from the National Educational Panel Study (NEPS) with additional data sources like the COVID-19-Dashboard of the Robert-Koch-Institut (RKI). Our results show that parental expectations of future school problems were particularly prevalent among those parents whose children had low reading competencies and low diligence as an aspect of school effort. In addition, we find a relationship between a lower occupational status (ISEI) and higher parental expectations of school-related problems. Furthermore, parents' short-term and long-term concerns about Covid-19 show a positive association, making school problems more likely in the eyes of the parents. The purpose of this paper, in addition to applying and explaining nonlinear models for the first time in empirical educational research, is to analyze expectations regarding problems of homeschooling in the first lockdown from a parents' perspective and to explore variables that influence these parental expectations.

A phase I trial of the single-chain immunotoxin SGN-10 (BR96 sFv-PE40) in patients with advanced solid tumors.

PURPOSE: Our purpose in the study was to establish the maximum tolerated dose and toxicity profile of SGN-10 (or BR96 sFv-PE40), a single-chain immunotoxin. SGN-10 is composed of the fused gene products encoding the translocating and ADP-ribosylating domains of Pseudomonas exotoxin (PE40) and the variable heavy (V(H)) and variable light (V(L)) regions of BR96 monoclonal antibody. This antibody is specific for a Lewis(Y) (Le(Y))-related carbohydrate antigen expressed on multiple carcinomas. EXPERIMENTAL DESIGN: A total of 46 patients with Le(Y)-positive metastatic carcinoma were enrolled in a Phase I dose-escalation study in cohorts of three to six patients who received SGN-10 at doses ranging from 0.024 to 0.962 mg/m(2), administered on days 1, 4, 8, and 11, followed by 2 weeks of rest and a second cycle of therapy. Pharmacokinetics and human antibody response to SGN-10 were also determined. RESULTS: The maximum tolerated dose of SGN-10 was 0.641 mg/m(2) with gastrointestinal dose-limiting toxicity. Pharmacokinetic studies performed in eight patients at the 0.641-mg/m(2) dose revealed a t([1/2]) of 2.5 +/- 0.3 h and a C(max) of 389 +/- 112 ng/ml. Pharmacodynamic analyses demonstrated a rapid clearance of the drug by day 11 associated with an antitoxin human antitoxin antibody (HATA) response in most patients. Signs consistent with a modest vascular leak syndrome, specifically, transient hypoalbuminemia, were observed in patients treated with doses of > or =0.384 mg/m(2). No complete or partial tumor responses were observed at an 8-week evaluation, although 31% of patients had stable disease. CONCLUSIONS: The maximal tolerated dose of SGN-10 given twice weekly for 2 weeks is 0.641 mg/m(2) with gastrointestinal dose-limiting toxicity. The immunogenicity of the toxin moiety limits the ability of SGN-10 to circulate by day 11 of therapy. Studies are ongoing to evaluate strategies to ameliorate toxicities and to inhibit the development of the anti-SGN-10 immune response.

Recombinant baculoviruses used to study estrogen receptor function in human osteosarcoma cells.

We report that modified baculoviruses, termed BacMam viruses, can efficiently deliver multiple genes into mammalian cells to generate a heterologous transcription factor/reporter gene system. Using human estrogen receptor (ER) as a model nuclear receptor, we demonstrate how this approach can be successfully applied to assay development in Saos-2 human osteosarcoma cells. BacMam viruses containing full-length cDNAs were constructed for both human ER subtypes, ERalpha and ERbeta, and a third BacMam virus containing an ER-responsive reporter gene cassette. Using these viruses, we found that BacMam-ER expression/reporter constructs could be used to profile the effects of the agonist 17beta-estradiol and the partial agonist raloxifene in human Saos-2 cells. A comparison of assay data obtained with the BacMam-based system with that using standard DNA transfections demonstrates that the two systems are functionally equivalent, giving comparable EC(50) and IC(50) values for estrogen and estrogen plus raloxifene treatments, respectively. Our results indicate that BacMam-mediated gene transfer offers a novel and efficient method for delivery of nuclear receptors and associated genes for mammalian cell-based assay development.

Anosognosia in schizophrenia: hidden in plain sight.

OBJECTIVE: Poor insight is a cardinal symptom of schizophrenia that, while not universally and uniformly expressed in all patients, is among the most common of its manifestations. Available neurobiological and neurocognitive evidence linking the phenomenon to core pathophysiology of schizophrenia justifies extension of the anosognosia construct to schizophrenia-related insight deficits. Poor insight is a core attribute of schizophrenia, occurring in 57 to 98 percent of patients. Insight is an important outcome predictor, associated with treatment adherence, relapse frequency, symptom remission, psychosocial functioning, vocational attainment, and risk of violence toward self or others. Combined findings lend urgency to the importance of reducing psychotic relapse. This can only be achieved in the majority of patients with consistent medication adherence- something that is often exceedingly difficult in patients lacking belief in the fact of their illness. This article examines whether anosognosia, the unawareness of deficit or illness, should apply to our understanding of insight deficits in patients with schizophrenia. Although research in the field is limited at this time, there is hope that anosognosia as a symptom of schizophrenia will become a focus of further research and a critically important therapeutic target amenable to treatment. DESIGN: This article is a literature review and conceptualization. CONCLUSION: Limited research in the field gives cause for hope that anosognosia as a symptom of schizophrenia will become a critically important therapeutic target that is amendable to treatment.

USGS48 Puerto Rico precipitation - a new isotopic reference material for δ2H and δ18O measurements of water.

A new secondary isotopic reference material has been prepared from Puerto Rico precipitation, which was filtered, homogenised, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity, and calibrated by dual-inlet isotope-ratio mass spectrometry. This isotopic reference material, designated as USGS48, is intended to be one of two isotopic reference waters for daily normalisation of stable hydrogen (δ(2)H) and stable oxygen (δ(18)O) isotopic analysis of water with a mass spectrometer or a laser absorption spectrometer. The δ(2)H and δ(18)O values of this reference water are-2.0±0.4 and-2.224±0.012 ‰, respectively, relative to Vienna Standard Mean Ocean Water on scales normalised such that the δ(2)H and δ(18)O values of Standard Light Antarctic Precipitation reference water are-428 and-55.5 ‰, respectively. Each uncertainty is an estimated expanded uncertainty (U=2u(c)) about the reference value that provides an interval that has about a 95 % probability of encompassing the true value. This isotopic reference water is available by the case of 144 glass ampoules containing 5 mL of water in each ampoule.

Sacroiliac injuries in horses.

This article reviews the pathology, diagnosis, and treatment of sacroiliac joint injuries. These injuries can be acute or chronic and can involve soft tissue structures surrounding the joint or the bony structures of the joint. The several diagnostic modalities for sacroiliac injuries vary in usefulness and accessibility. Treatment of sacroiliac problems is usually supportive and nonspecific and includes the use of antiinflammatory medications and an appropriate exercise regimen. The prognosis depends on the cause, but severe injuries can limit a horse's future athletic activity.