Absolute Value Of Difference Research Articles

Determination of hydroxyl value of vegetable oils‐based polyols through ring‐preopening, solvent‐extraction, and acetylation method

AbstractVegetable oils‐based polyols prepared by epoxidation‐hydroxylation often have the phenomenon of the coexistence of epoxy and hydroxyl groups due to different ring‐opening degrees. The acylation method recommended by the American Society of Testing Materials (ASTM) standard (D1957‐86) and the Association of Official Analytical Chemists (AOAC) standard (965.32) is applicable only to fatty alcohols in oils and fats and their derivatives but not to vegetable oils‐based polyols since the residual epoxy groups in vegetable oils‐based polyols lead the tested hydroxyl value (OHV) to be higher than the actual OHV. A method combining ring‐preopening of residual epoxy groups, ether extraction of ring‐preopened vegetable oils‐based polyols, and subsequent acetylation by acetic anhydride‐acetic acid was established for OHV determination of vegetable oils‐based polyols. The accuracy of the method was verified by the known theoretical OHVs of short‐chain alcohols and simulated vegetable oils‐based polyols. The absolute values of relative deviations for OHVs of short‐chain alcohols and simulated vegetable oils‐based polyols were within 1.0% and 3.1%, respectively, which indicates the feasibility of the established method in eliminating the negative effects of residual epoxy groups in vegetable oils‐based polyols on OHV determination as well as accurately determining and evaluating the OHV of vegetable oils‐based polyols. The method can broaden the range of OHV determination up to 1800 mg KOH/g. The ratio of acetic anhydride and acetic acid and reaction time are key factors affecting the complete degree of acetylation, which can be regulated mutually in accurately determining the OHV of vegetable oils‐based polyols according to the practice. It is the first time, to our best knowledge, to establish a method to eliminate the negative effects of residual epoxy groups in vegetable oils‐based polyols on OHV determination. The established method provides a feasible method for polyol industry to accurately evaluate the product quality of vegetable oils‐based polyols.

Optic nerve head factors associated with initial central visual field defect in primary open-angle glaucoma

We investigated optic nerve head factors associated with initial parafoveal scotoma (IPFS) in primary open-angle glaucoma. Eighty (80) patients with an IPFS and 84 patients with an initial nasal step (INS) were compared. Central retinal vascular trunk (CRVT) deviation from the Bruch’s membrane opening (BMO) center was measured as a surrogate of lamina cribrosa (LC)/BMO offset, and its obliqueness was defined as the absolute value of angular deviation from the fovea-BMO axis. Proximity of retinal nerve fiber layer defect (RNFLD) was defined as the angular deviation of the inner RNFLD margin from the fovea-BMO axis. Microvasculature dropout (MvD) was defined as a focal sectoral capillary dropout with no visible microvascular network identified in the choroidal layer. Factors associated with IPFS, as compared with INS, were assessed using logistic regression analyses and conditional inference tree analysis. The IPFS group had more oblique CRVT offset (P < 0.001), RNFLD closer to the fovea (P < 0.001), more MvD (P < 0.001), and more LC defects (P < 0.001) compared to the INS group. In logistic regression analyses, obliqueness of CRVT offset (P = 0.002), RNFLD proximity (P < 0.001), and MvD (P = 0.001) were significant factors influencing the presence of IPFS. Conditional inference tree analysis showed that RNFLD closer to the fovea (P < 0.001) in the upper level, more oblique CRVT offset (P = 0.013) and presence of MvD (P = 0.001) in the lower level were associated with the probability of having IPFS. IPFS was associated with closer RNFLD location to the fovea when assessed from the BMO. Oblique LC/BMO offset may not only mask RNFLD proximity to the fovea due to a deviated funduscopic disc appearance, but also potentiate IPFS via focal LC defect and MvD.

Adsorptive uptake of thymol blue from aqueous medium using calcined snail shells: equilibrium, kinetic, thermodynamic, neuro-fuzzy and DFT studies

ABSTRACTS The spontaneous discharge of pollutants or toxicants into the ecosystem as a result of various anthropogenic activities is alarming, this necessitates a drastic cheap, and eco-friendly clean-up approach. Out of all the methods, adsorption has proven to be the most effective. The batch adsorptive removal of Thymol Blue (TB) dye from aqueous solutions is examined in this study utilizing calcined snail shells (CalSS). With the aid of SEM, EDS, XRD, and FTIR, the synthesized adsorbent was examined for different physicochemical characteristics. A machine learning model namely Adaptive Neuro-Fuzzy Inference System (ANFIS) was developed to assess the TB adsorption process while taking into account the important adsorption parameters contact time, temperature, pH, adsorbent dosage, then initial adsorbate concentration. Adsorbent pHpzc was also evaluated. EDX and FTIR confirm the formation of CaO with sharp peaks at 547 cm−1 and C–O and O–H are present. SEM and XRD show an irregularly shaped highly crystalline adsorbent material having a typical particle size of 65 ± 2.81 nm and lattice parameter value of 8.611617 Å. The pHpzc value is 11.04, indicating basic surface characteristics. The pH of 3.0, an adsorbent dose of 10 mg and the highest achievable adsorption efficiency were measured to be 98.75% at 20 °C. The findings from the study fit nicely onto Brouser Sotolongo with q BS = 259.4887 mg/g and R 2 = 0.9888. The pseudosecond order model (PSOM) recorded the least error value of 0.3336 and R 2 = 0.9952. This indicates chemisorption and multilayer adsorption processes. The thermodynamic parameters ΔH° and ΔG° demonstrate the exothermic and spontaneous nature of the adsorption process. The ANFIS model for the TB sequestration was evaluated using relevant statistical metrics, giving Root Mean Square Error (RMSE) value of 1.4644, Mean Absolute Deviation (MAD) value of 0.576, Mean Absolute Error (MAE) value of 1.2974 and Mean Absolute Percentage Error (MAPE) value of 1.5141. This outcome revealed that the ANFIS model and experimental findings are in good agreement. The efficacy of calcined snail shell in removing Thymol Blue dye from aqueous solution was also examined using in-silico technique which was in accordance to the value of the calculated descriptors obtained from the adsorbent as well as the calculated binding affinity. The elimination of TB-polluted wastewater using calcined snail shells is demonstrated in this study to be a successful and environmentally benign process.

Global mapping of fractional tree cover for forest cover change analysis

Fractional tree cover facilitates the characterization of forest cover changes using satellite data. However, there are still substantial challenges in generating fractional tree cover datasets that satisfy the requirements of interannual stability for forest cover change monitoring. In this study, a global annual fractional tree cover dataset, named as GLOBMAP Fractional Tree Cover, was generated from MODIS observations with a resolution of 250 m during the period of 2000–2022. The tree cover estimation was improved relative to conventional global tree cover mapping methods by developing highly discriminative input features and near global sampling training data. MODIS annual observations were realigned at the pixel level to eliminate phenological differences among regions. The realigned annual series were condensed into twelve features showing high separability between trees and herbaceous vegetation to reduce the dimension of features. A global covering training dataset, comprising 465.88 million sample points, was extracted across the globe through the aggregation and combination of forest/land cover maps from ESA WorldCover, GlobeLand30, PALSAR FNF, and ESRI Land Cover to improve the representativeness of training data. A feed-forward neural network was calibrated to predict fractional tree cover from MODIS data. The spatial pattern of the estimation results was generally consistent with the CGLS-LC100 product at global scale, with the average MAE in global vegetated areas of 12.50 %, while our dataset provided extended temporal coverage. The interannual stability of the estimated tree cover series was improved compared to MODIS vegetation continuous fields products for deciduous broadleaf forests, evergreen broadleaf forests, and mixed forests, with the global average value of mean absolute deviation (MAD) in tree cover series reduced by 5.8 %, 46.9 %, and 18.3 %, respectively. The estimation results were assessed using globally distributed validation data around BELMANIP 2.1 sites and those derived from the USGS circa 2010 global land cover reference dataset, leading to the R2 values of 0.93 and 0.73, MAE of 4.24 % and 10.55 %, and RMSE of 11.45 % and 17.98 %, respectively. This dataset could enhance the capability to monitor forest cover changes, particularly gradual changes such as forest recovery.

Effect of Low-Dose Recombinant Interleukin-2 Therapy on Immunocyte Subsets in Children with Solid Tumor

To evaluate the effect of low-dose recombinant interleukin-2 (rIL-2) therapy on immunocyte subsets and its side effects in children with solid tumor. A total of 22 children (11 males and 11 females) with solid tumor in our department from December 2012 to November 2017 were selected, with a median age of 9 (3-16) years old when starting IL-2 therapy. ALL surgeries and chemotherapy of children had been completed before low-dose rIL-2 therapy, and 17 cases achieved complete remission (CR) and 5 cases achieved partial remission (PR). A low-dose rIL-2 therapy was given 1 month after chemotherapy for 1 year: 4×105 IU/(m2·d), s.c. for every other day, 3 times per week. The immunocyte subsets were detected every 3 months until the end of treatment, meanwhile, disease condition and therapy-related side effects were followed up. After low-dose rIL-2 therapy in 22 children, the absolute values of CD3+ T cells, CD3-CD56+ natural killer cells, CD3+CD4+ helper T cells (Th) and CD3+CD8+ cytotoxic T cells were up-regulated remarkably, as well as Th/suppressor T cells (all P < 0.05). While, there were no significant differences in absolute value and proportion of CD4+CD25+CD127- Treg cells during therapy. Among the 17 children who achieved CR before rIL-2 therapy, 14 cases continued to maintain CR after therapy, while 3 cases relapsed, and with 2 died after treatment abandonment. The 5 children who achieved PR before low-dose rIL-2 therapy were evaluated CR by PET/CT scan after treatment. In the early stage of low-dose rIL-2 therapy, 1 child developed skin rashes at the injection sites, and 2 children ran a slight to mild transient fever. Their symptoms disappeared without any organ damage after symptomatic treatment. Low-dose rIL-2 therapy has good drug tolerance, and changes the distribution of anti-tumor immune-cell subgroup in peripheral blood of children with solid tumor remarkably without up-regulation of absolute value and ratio of Treg cells.

The effect of the back optic zone diameter on the treatment zone area and axial elongation in orthokeratology.

To investigate the influence of corneal parameters on the treatment zone area (TZA) after Corneal Refractive Therapy (CRT) with a 5.0-mm back optical zone diameter (BOZD) were worn and to compare changes in the axial length (AL) with traditional 6.0-mm BOZD lenses. This retrospective study involved 146 subjects (7-12years) who wore orthokeratology (ortho-K) lenses for one year: 86 subjects were treated with CRT 5.0-mm lenses, and 60 subjects were treated with CRT 6.0-mm lenses. The TZA was measured after one year of ortho-K treatment. Both TZA and AL elongation after wearing the two kinds of lenses was compared. The parameters were recorded in the CRT 5.0 group: flat K, steep K, corneal toricity, e value, and anterior corneal elevation values at the 3-, 4-, and 5-mm chords along the principal meridians of the superior, inferior, nasal, and temporal sides. The relationships between these data and the TZA were analyzed. The TZA was 12.90±5.15mm2 and 20.61±4.54mm2, and the AL elongation was 0.15±0.18mm and 0.26±0.18mm in the CRT 5.0 group and the CRT 6.0 group, respectively (all p<0.001). The one-year AL elongation was significantly associated with initial age and the TZA (r=-0.394, 0.393; all p<0.001) in the CRT 5.0 group. The following corneal parameters were found to have statistically significant correlations with the TZA: the e value, difference in corneal elevation (nasal-temporal at the 3-, 4-, and 5-mm chord), and the absolute value of elevation difference (nasal-temporal at the 3- and 4-mm chord and inferior-superior at the 3-, 4-, and 5-mm chord). The e value was the only relevant factor for the TZA by multiple regression analysis (unstandardized β=14.219, p=0.008). In the CRT 6.0 group, the one-year AL elongation was statistically significantly associated only with initial age (r=-0.605, p=0.005), but not with the TZA (p=0.161). A smaller TZA induced by a smaller BOZD may be beneficial for retarding AL elongation in children undergoing ortho-K treatment. The morphology and eccentricity of the cornea may show effects on the TZA.

Effects of Accelerated Rehabilitation Exercise on the Senior Fitness Test (SFT), Isometric Muscle strength, and Blood Profile in Older Adult Women with Degenerative Knee Osteoarthritis

PURPOSE This study aimed to investigate the effects of accelerated rehabilitation exercise on physical fitness, lower extremity isometric strength, and blood variables in older adult women diagnosed with degenerative osteoarthritis.METHODS A total of 29 older adult women diagnosed with degenerative osteoarthritis residing in G city participated in the study, and 19 participants, excluding dropouts, took part in the experiment. They underwent exercise twice a week for 60 minutes per session over a period of 12 weeks. Pre- and post-experiment, the older adult fitness assessment (SFT), lower extremity isometric strength, and blood variables were measured. Data analysis was performed using SPSS 25.0, and paired sample t-tests were conducted to examine the effects before and after exercise.RESULTS The study results showed significant differences in body mass index (BMI) before and after exercise (p&lt;0.05), and the older adult fitness assessment (SFT) showed significant differences in all items (p&lt;0.01). Lower extremity isometric strength showed significant differences in absolute (Nm) and relative (%BW) values of 20° right flexion muscle (p&lt;0.01). In terms of blood variables, significant differences were observed in creatine and ESR before and after exercise (p&lt;0.01).CONCLUSIONS This study’s results suggest that regular physical activity and rehabilitation exercise programs can positively impact the muscular strength, cardiovascular endurance, exercise function, and blood composition of older adult women diagnosed with degenerative osteoarthritis. It is indicated that conducting future research, including periodic exercise programs, could be beneficial in promoting sustained exercise participation.

Clinical Result of One-Piece Aspheric Intraocular Lens in Mild Zonule-Weakness

Purpose: To compare the clinical outcomes of one-piece aspheric intraocular lens in the patient group with mild zonule weakness and control group.Method: Among the patients who underwent cataract surgery since 2017, 30 patients (average age of 68.26 ± 8.99 years, 14 men, 16 women) and 35 eyes were selected. Prior to surgery, information on LOCS staging, endothelial cell count, intraocular pressure, axial length, and corneal refractive index were analyzed retrospectively. The average follow-up period after surgery was 3 months. The absolute value of the difference between the spherical equivalent value and the target refractive value in the patient group and the control group at 1 month and 3 months after surgery was compared.Results: The absolute value of the difference in refractive value after 1 month in the patient group was found was 0.61 ± 0.41 Diopters and 0.51 ± 0.42 Diopters in the control group, showing no statistically significant difference (&lt;i&gt;p&lt;/i&gt; &gt; 0.05). After 3 months, the absolute value of the refractive value difference was 0.46 ± 0.27 Diopters in the patient group and 0.46 ± 0.32 Diopters in the control group, indicating no statistically significant difference (&lt;i&gt;p&lt;/i&gt; &gt; 0.05).Conclusions: The one-piece aspheric intraocular lens enVista MX60 does not show statistically significant clinical difference in the difference between the postoperative refractive value and the target refractive value in the patient group, so it may be actively considered for use in the patient with mild zonule weakness.

Clinical application of real-time continuous glucose monitoring system during postoperative enteral nutrition therapy in esophageal cancer patients.

Enteral nutrition (EN) support therapy increases the risk of abnormal blood glucose (BG). The aim of this study is to evaluate the clinical value of a real-time continuous glucose monitoring (rt-CGM) system in BG monitoring during postoperative EN support therapy in patients with esophageal cancer. Patients without diabetes mellitus (DM) with esophageal cancer who planned to receive postoperative EN were enrolled. With the self-monitoring of BG value as the reference BG, the accuracy of rt-CGM was evaluated by the mean absolute relative difference (MARD) value, correlation efficient, agreement analysis, and Parkes and Clarke error grid plot. Finally, paired t tests were used to compare the differences in glucose fluctuations between EN and non-EN days and slow and fast days. The total MARD value of the rt-CGM system was 13.53%. There was a high correlation between interstitial glucose and fingertip capillary BG (consistency correlation efficient = 0.884 [95% confidence interval, 0.874-0.894]). Results of 15/15%, 20/20%, 30/30% agreement analysis were 58.51%, 84.71%, and 99.65%, respectively. The Parkes and Clarke error grid showed that the proportion of the A and B regions were 100% and 99.94%, respectively. The glucose fluctuations on EN days vs non-EN days and on fast days vs slow days were large, and the difference was statistically significant (P < 0.001). The rt-CGM system achieved clinical accuracy and can be used as a new option for glucose monitoring during postoperative EN therapy. The magnitude of glucose fluctuation during EN therapy remains large, even in the postoperative population without DM.

Rheological Study on Blend Solutions of Non-mulberry Silk Fibroin and Gelatin Biopolymers

In current research work, we have studied the blending effect of non-mulberry silk fibroin (10% weight/volume basis) and gelatin (20% weight/volume basis) in formic acid. Several blends as SF10G0, SF2G8, SF3G7, SF5G5 and SF0G10 have been made and their rheological behaviour was investigated. The blend solutions were subjected to a steady shear rheological study in the variety of range of shear rates, namely 0.01–500 sec-1 and the viscosities of blend solutions were noticed to decrease in comparison to pure silk solution. The frequency sweep was employed in dynamic rheological tests to determine complex viscosity of these solutions from range of angular sweep 0.1–100 rad/sec. The consistent shear-thinning behaviour was noted for all the blends. The difference in numerical values of shear and complex viscosities indicated disobedience of Cox-Merz rule. Such analysis can be utilised for tailoring the properties of solution prior to processing them to create a versatile range of materials.

EFFECT OF STRATIFIED DOSE OF NOREPINEPHRINE ON CELLULAR IMMUNE RESPONSE IN PATIENTS WITH SEPTIC SHOCK AND THE CONSTRUCTION OF A PROGNOSTIC RISK MODEL.

Objective: To explore the effect of a stratified dose of norepinephrine (NE) on cellular immune response in patients with septic shock, and to construct a prognostic model of septic shock. Methods: A total of 160 patients with septic shock (B group) and 58 patients with sepsis (A group) were given standard cluster therapy. Patients with septic shock were divided into four groups (B1-B4 groups: 0.01-0.2, 0.2-0.5, 0.5-1.0, and >1 μg/kg/min) according to the quartile method of the early (72 h) time-weighted average dose of NE and clinical application. The cellular immune indexes at 24 h (T0) and 4-7 days (T1) after admission were collected. The difference method was used to explore the effect of NE stratified dose on cellular immune effect in patients with septic shock. A multivariate COX proportional risk regression model was used to analyze the independent prognostic risk factors, and a prognostic risk model was constructed. Results: The differences of ΔIL-1β, ΔIL-6, ΔIL-10, absolute value difference of T lymphocyte (ΔCD3+/CD45+#) and Th helper T cell (ΔCD3+ CD4+/CD45+#), CD64 infection index difference, ΔmHLA-DR, regulatory T lymphocyte ratio difference (ΔTregs%) between group A, B1, B2, B3, and B4 were statistically significant ( P < 0.05). There was a nonlinear relation between the stratified dose of NE and ΔIL-6, ΔIL-10, ΔCD3+/CD45+#, ΔmHLA-DR%. The threshold periods of NE-induced proinflammatory and anti-inflammatory immune changes were 0.3-0.5 μg/kg/min. Multivariate COX model regression analysis showed that age, nutritional patterns, weighted average dose of norepinephrine, IL-6, absolute value of T lymphocytes, and mHLA-DR were independent risk factors affecting the prognosis of patients with septic shock ( P < 0.05). The prognostic risk model was constructed (AUC value = 0.813, 95% CI: 0.752-0.901). Conclusion: NE has a certain inhibitory effect on cellular immune function in patients with septic shock. A prognostic risk model was constructed with stronger prediction efficiency for the prognosis of patients with septic shock.

Factors Affecting the Integrity of Financial Statements with Company Size as a Moderation Variable

This study aims to examine the effect of audit quality, audit committee, leverage, and independent commissioners on the integrity of financial statements in manufacturing companies listed on the Indonesia Stock Exchange in 2019-2021. This study also examines whether company size can moderate the respective relationship between audit quality, audit committee, leverage, and independent commissioners on the integrity of financial statements. This study used a quantitative approach with a comparative causal type. The population in this study is all manufacturing companies listed on the Indonesia Stock Exchange in 2019-2021. The sampling technique uses purposive sampling. The data used in this study is secondary data accessed through the IDX website. Data analysis uses multiple regression analysis for audit quality hypothesis, audit committee, leverage, and the independent commissioner as well as absolute difference value analysis for audit quality, audit committee, leverage, and independent commissioner on financial statement integrity with company size as a moderation variable. The results of this study show that the quality of audits, audit committees, leverage, and independent commissioners have a positive and significant effect on the integrity of financial statements. The moderation variable is the size of the company able to moderate the relationship between audit quality, audit committee, and leverage on the integrity of financial statements.

Variable Performance of D-dimer Testing by Hemostasis Laboratories: The Australasian/Asia-Pacific Experience.

D-dimers represent the breakdown products of fibrin. Thus, elevated plasma D-dimers will arise following a thrombotic event, such as a deep vein thrombosis or a pulmonary embolism, and therefore, a nonelevated D-dimer is used to effectively exclude such events. D-dimers are also elevated in a range of other conditions, for example, during disseminated intravascular coagulation. D-dimer levels may also be associated with prognostic value. For example, highly raised D-dimer levels can be associated with worsening clinical features in coronavirus disease 2019. Thus, D-dimer testing represents a commonly requested hemostasis test, often performed in 24/7 laboratories. Unfortunately, D-dimer testing is neither standardized nor harmonized across manufacturers or laboratories. Indeed, considering reporting units and the magnitude of units, up to 28 different combinations may be reported by laboratories. We provide updated findings for D-dimer testing in our geographic region, using recent data from the Royal College of Pathologists of Australasia Quality Assurance Programs, an international external quality assessment program, currently with over 450 participants in the D-dimer module. Data show a wide variety of assays in use and variable outcomes in reported numerical values when assessing proficiency samples. D-dimer testing mostly comprised reagents from three main manufacturing suppliers, with a small number of users of reagents from other manufacturers. Reported results showed important differences in numerical values for the same homogeneous tested samples when normalized to a single reporting unit (e.g., mg/L). Nevertheless, despite using different test reagents and reporting, most participants uniformly identified D-dimer values as below or above a "detection" cut-off for samples that were constructed to be below or above most cut-off values. As expected, mixed findings were reported for samples containing levels around expected cut-off values. We hope that our findings, reflecting on the heterogeneity of test reagents and test data, help improve diagnostic testing for D-dimer testing and facilitate harmonization and standardization, in the future.

The Effect of Material Flow Cost Accounting on Company Sustainability: Moderating Role of Green Accounting in Consumer Goods Industry Companies

This study analyzes the influence of material flow cost accounting in improving company sustainability. Material flow cost accounting. This research uses proxies for production costs, factory area, and output or production value. The population used in this research is all goods and consumption companies listed on the IDX for the 2015-2021 period. Through Purposive sampling, the samples obtained were 6 companies in that period, so 42 data were obtained. Data processing in this research was carried out using multiple regressions and moderated regression methods with an absolute difference value approach. This research concludes that MFCA (production costs) negatively and significantly affects company sustainability. This means that reducing production costs to get higher profits will increase the company's sustainability. Meanwhile, MFCA (factory area and output or production value) positively and significantly influences company sustainability. This shows that the wider the company's area and every time there is an increase in production results, the company's sustainability can increase. Besides, green accounting cannot moderate material flow cost accounting on company sustainability.

Is epidural analgesia non-inferior to intrathecal fentanyl as initiation for neuraxial analgesia in early non-spontaneous labour?

Intrathecal fentanyl, using the combined spinal-epidural (CSE) technique, provides rapid analgesia during early labour. Because of the technique's more complex and invasive nature, as its replacement we assessed the use of epidural analgesia in primiparous parturients with induced labour. The study was registered at www. gov (NCT04645823). The aim was to compare the efficacy, duration of analgesia and maternal satisfaction. The primary outcome was the difference in pain visual analogue scale (VAS) between the interventions at 20 min after the analgesia administration. Sixty volunteering parturients were randomly allocated in 1:1 ratio to receive either intrathecal fentanyl 20 μg or epidural analgesia (fentanyl 100 μg and lidocaine 80 mg). Contraction pain and maternal satisfaction were assessed by 0-100 mm VAS for 30 min, respectively. Foetal heart rate abnormalities, the time to first epidural dose and the incidence of pruritus were recorded. Non-inferiority margin for mean (95% CI) VAS after epidural analgesia was set at 20 mm above the VAS value for intrathecal fentanyl at 20 min. The contraction pain VAS fell from (median [interquartile range, IQR]) 82 (14) to 13 (20) mm and 76 (17) to 12 (27) mm in 20 min following the intrathecal fentanyl and epidural analgesia, respectively. The absolute mean difference (epidural-intrathecal fentanyl) in the VAS values was 3.3(-0.06 to 6.66) mm indicating non-inferiority. The median time to reach VAS <30 mm was 10 min in both groups. The duration until request for supplemental analgesia was 82(69-95) and 91(75-106) min after intrathecal fentanyl and epidural analgesia, respectively. The difference for the duration (epidural-intrathecal fentanyl) was 9 (6-12) min and for satisfaction-VAS 0.3 (-3.0 to 3.7) mm. There were no differences between the groups in the incidence of foetal heart rate abnormalities, while pruritus was more common after intrathecal fentanyl. After 20 min, epidural analgesia by lidocaine and fentanyl was within the non-inferior threshold compared with intrathecal fentanyl in efficacy. The duration of action was not shorter than that of intrathecal fentanyl and maternal satisfaction was also similar.

Simulation and pre-planning omitted radiotherapy (SPORT): a feasibility study for prostate cancer

This study explored the feasibility of on-couch intensity modulated radiotherapy (IMRT) planning for prostate cancer (PCa) on a cone-beam CT (CBCT)-based online adaptive RT platform without an individualized pre-treatment plan and contours. Ten patients with PCa previously treated with image-guided IMRT (60 Gy/20 fractions) were selected. In contrast to the routine online adaptive RT workflow, a novel approach was employed in which the same preplan that was optimized on one reference patient was adapted to generate individual on-couch/initial plans for the other nine test patients using Ethos emulator. Simulation CTs of the test patients were used as simulated online CBCT (sCBCT) for emulation. Quality assessments were conducted on synthetic CTs (sCT). Dosimetric comparisons were performed between on-couch plans, on-couch plans recomputed on the sCBCT and individually optimized plans for test patients. The median value of mean absolute difference between sCT and sCBCT was 74.7 HU (range 69.5–91.5 HU). The average CTV/PTV coverage by prescription dose was 100.0%/94.7%, and normal tissue constraints were met for the nine test patients in on-couch plans on sCT. Recalculating on-couch plans on the sCBCT showed about 0.7% reduction of PTV coverage and a 0.6% increasing of hotspot, and the dose difference of the OARs was negligible (<0.5 Gy). Hence, initial IMRT plans for new patients can be generated by adapting a reference patient’s preplan with online contours, which had similar qualities to the conventional approach of individually optimized plan on the simulation CT. Further study is needed to identify selection criteria for patient anatomy most amenable to this workflow.

Exploring Alternate Methods for the Calculation of High-Level Vibrational Corrections of NMR Spin-Spin Coupling Constants.

Traditional nuclear magnetic resonance (NMR) calculations typically treat systems with a Born-Oppenheimer-derived electronic wave function that is solved for a fixed nuclear geometry. One can numerically account for this neglected nuclear motion by averaging over property values for all nuclear geometries with a vibrational wave function and adding this expectation value as a correction to an equilibrium geometry property value. Presented are benchmark coupled-cluster singles and doubles (CCSD) vibrational corrections to spin-spin coupling constants (SSCCs) computed at the level of vibrational second-order perturbation theory (VPT2) using the vibrational averaging driver of the CFOUR program. As CCSD calculations of vibrational corrections are very costly, cheaper electronic structure methods are explored via a newly developed Python vibrational averaging program within the Dalton Project. Namely, results obtained with the second-order polarization propagator approximation (SOPPA) and density functional theory (DFT) with the B3LYP and PBE0 exchange-correlation functionals are compared to the benchmark CCSD//CCSD(T) and experimental values. CCSD//CCSD(T) corrections are also combined with literature CC3 equilibrium geometry values to form the highest-order vibrationally corrected values available (i.e., CC3//CCSD(T) + CCSD//CCSD(T)). CCSD//CCSD(T) statistics showed favorable statistics in comparison to experimental values, albeit at an unfavorably high computational cost. A cheaper CCSD//CCSD(T) + B3LYP method showed quite similar mean absolute deviation (MAD) values as CCSD//CCSD(T), concluding that CCSD//CCSD(T) + B3LYP is optimal in terms of cost and accuracy. With reference to experimental values, a vibrational correction was not worth the cost for all of the other methods tested. Finally, deviation statistics showed that CC3//CCSD(T) + CCSD//CCSD(T) vibrational-corrected equilibrium values deteriorated in comparison to CCSD//CCSD(T) attributed to the use of a smaller basis set or lack of solvation effects for the CC3 equilibrium calculations.

Reproducibility of 3D pH-weighted chemical exchange saturation transfer contrast in the healthy cervical spinal cord.

Spinal cord ischemia and hypoxia can be caused by compression, injury, and vascular alterations. Measuring ischemia and hypoxia directly in the spinal cord noninvasively remains challenging. Ischemia and hypoxia alter tissue pH, providing a physiologic parameter that may be more directly related to tissue viability. Chemical exchange saturation transfer (CEST) is an MRI contrast mechanism that can be made sensitive to pH. More specifically, amine/amide concentration independent detection (AACID) is a recently developed endogenous CEST contrast that has demonstrated sensitivity to intracellular pH at 9.4 T. The goal of this study was to evaluate the reproducibility of AACID CEST measurements at different levels of the healthy cervical spinal cord at 3.0 T incorporating B1 correction. Using a 3.0 T MRI scanner, two 3D CEST scans (saturation pulse train followed by a 3D snapshot gradient-echo readout) were performed on 12 healthy subjects approximately 10 days apart, with the CEST volume centered at the C4 level for all subjects. Scan-rescan reproducibility was evaluated by examining between and within-subject coefficients of variation (CVs) and absolute AACID value differences. The C4 level of the spinal cord demonstrated the lowest within-subject CVs (4.1%-4.3%), between-subject CVs (5.6%-6.3%), and absolute AACID percent difference (5.8-6.1%). The B1 correction scheme significantly improved reproducibility (adjusted p-value = 0.002) compared with the noncorrected data, suggesting that implementing B1 corrections in the spinal cord is beneficial. It was concluded that pH-weighted AACID measurements, incorporating B1-inhomogeneity correction, were reproducible within subjects along the healthy cervical spinal cord and that optimal image quality was achieved at the center of the 3D CEST volume.

Estimation of size-specific dose estimate (SSDE) of CT scans using an effective diameter electron density

ObjectiveAn assessment of the effective diameter of a patient’s body using electron densities of tissues inside the scan area (Deffρe) was proposed to overcome challenges associated with the estimation of water-equivalent diameter (Dw), which is used for size-specific dose estimate (SSDE). The aims of this study were to (1) investigate the Deffρe method in two different forms using a wide range of patient sizes and scanning protocols, and (2) compare between four methods used to estimate the patient size for SSDE. Materials and methodsUnder IRB approval, a total of 350 patients of varying sizes have been collected retrospectively from the Hospital. The Dw values were assessed over six different CT body protocols: (1) chest with contrast media, (2) chest High-Resolution Computed Tomography (HRCT) without contrast media, (3) abdomen-pelvis with contrast media, (4) abdomen-pelvis without contrast media, (5) chest-abdomen-pelvis with contrast media, and (6) pelvis without contrast media. A MATLAB-based code was developed in-house to assess the size of each patient using the conventional effective diameter method (Deff), Deffρe by correcting either both the lateral (LAT) and anterior-posterior (AP) dimensions (Deff,LAT+APρe) or LAT only (Deff,LATρe), and Dw at the mid-CT slice of the patient images. ResultsThe results of Deff,LAT+APρe and Deff,LATρe provided a better estimation for the chest protocols with the averages of absolute percentage difference (PD) values in the range of 3 – 7 % for all patient sizes as compared to the Dw method, whereas the averages of PD values for the Deff method were 9 – 15 %. However, Deff gave a better estimation for Dw values for the other body protocols, with differences of 2 – 4 %, which were lower than those obtained with the Deff,LAT+APρe and Deff,LATρe methods. For the chest protocols, statistically significant differences were found between Deff and the other methods, but there were no significant differences between all the methods for the other scanning protocols. The results show that the correction of both dimensions, LAT and AP, did not improve the accuracy of the Deffρe method, and, for most protocols, Deff,LAT+APρe gave larger range differences compared to those based on correction of the LAT dimension only. ConclusionIf the Dw cannot be assessed, the Deff,LATρe method may only be considered for the chest protocols as an alternative approach. The Deff method may also be used for all regions taking into account the application of a correction factor for the chest protocols to avoid a significant under or overestimation of the patient dose.

Does matrix transducer technology improve quality and repeatability of four-dimensional tricuspid annular plane systolic excursion and mitral annular plane systolic excursion measurements?

Novel ultrasound technology and software processing allow offline evaluation of tricuspid annular plane systolic excursion and mitral annular plane systolic excursion measurements. We wished to compare both novel 4D matrix (eM6C) and conventional (RAB6-D) transducers with variable settings (electronic spatiotemporal image correlation, spatiotemporal image correlation and four-dimensional real time) to determine if there was a significant difference in absolute value, quality and repeatability of the resultant reconstructed image and M-mode trace. A blinded prospective cross-sectional study of normal fetuses from 23 to 38 weeks' gestation were recruited. After routine sonography, four-dimensional volumes were stored and analysed using GE 4DView™ software. Statistical analysis explored variability, correlations and repeatability of the measurements with chi-square analysis, intraclass correlations and the Bland-Altman comparison plots. A scoring system was devised for image quality. Eighteen participants generated 282 data volumes. Absolute values demonstrated some inconsistencies for both tricuspid annular plane systolic excursion and mitral annular plane systolic excursion measurements with variations between transducers: the highest for the RAB6-D/spatiotemporal image correlation setting and the lowest for the four-dimensional real-time settings. The RAB6-D/spatiotemporal image correlation setting was the most repeatable combination (intraclass correlation coefficient = 0.85). Poorest image quality (M-mode trace, four-chamber view, annuli) came from the RAB6-D/four-dimensional real-time combination with the eM6C/electronic spatiotemporal image correlation and RAB6-D/spatiotemporal image correlation settings being nearly identical. We show that transducer and setting combinations influence absolute tricuspid annular plane systolic excursion/mitral annular plane systolic excursion measurements, so need to be articulated in future research. The transducer setting (electronic spatiotemporal image correlation/spatiotemporal image correlation/four-dimensional real time) was a more significant factor than the type of transducer (conventional vs matrix). Subjective image evaluation does not correlate well with repeatability of image acquisition. Further studies are needed to compare measurements using four-dimensional post-processing tools against conventional real-time measurements.