Deviation of Latitude Cut: A Simple Sign to Differentiate Total Hip Arthroplasty from Hemiarthroplasty in Radiography.

This study aims to propose latitude cut deviation for differentiating hip arthroplasty types and evaluate its diagnostic utility in distinguishing total hip arthroplasty (THA) from hemiarthroplasty using radiography. After assessing various cup designs from top manufacturers for THA and hemiarthroplasty, we conducted a retrospective study on 40 patients (20 THA and 20 hemiarthroplasty). Three readers independently evaluated the radiographs, assessing acetabular sparing, cup-bone interface texture, and latitude cut deviation. Diagnostic performance and inter-observer agreement were compared using receiver operating characteristic curves and the Fleiss kappa coefficient. Latitude cut deviation measured on implant designs ranged from 19% to 42% in hemiarthroplasty and from -12% to 9% in THA. The sensitivity, specificity, and accuracy used to distinguish THA from hemiarthroplasty were 60-85%, 55-95%, and 62.5-77.5% for acetabular sparing; 100%, 50-80%, and 75-90% for cup-bone interface texture; and 100%, 90-100%, and 95-100% for latitude cut deviation. Inter-observer agreement for acetabular sparing, cup-bone interface texture, and latitude cut deviation ranged from moderate to excellent (κ = 0.499, 0.772, and 0.900, respectively). The latitude cut deviation exhibited excellent diagnostic performance and inter-reader agreement in distinguishing hemiarthroplasty from THA on radiographs, offering a concise way to identify hip arthroplasty type.

The diagnostic performance and clinical value of deep learning-based nodule detection system concerning influence of location of pulmonary nodule.

BACKGROUND: The deep learning-based nodule detection (DLD) system improves nodule detection performance of observers on chest radiographs (CXRs). However, its performance in different pulmonary nodule (PN) locations remains unknown. METHODS: We divided the CXR intrathoracic region into non-danger zone (NDZ) and danger zone (DZ). The DZ included the lung apices, paramediastinal areas, and retrodiaphragmatic areas, where nodules could be missed. We used a dataset of 300 CXRs (100 normal and 200 abnormal images with 216 PNs [107 NDZ and 109 DZ nodules]). Eight observers (two thoracic radiologists [TRs], two non-thoracic radiologists [NTRs], and four radiology residents [RRs]) interpreted each radiograph with and without the DLD system. The metric of lesion localization fraction (LLF; the number of correctly localized lesions divided by the total number of true lesions) was used to evaluate the diagnostic performance according to the nodule location. RESULTS: The DLD system demonstrated a lower LLF for the detection of DZ nodules (64.2) than that of NDZ nodules (83.2, p = 0.008). For DZ nodule detection, the LLF of the DLD system (64.2) was lower than that of TRs (81.7, p < 0.001), which was comparable to that of NTRs (56.4, p = 0.531) and RRs (56.7, p = 0.459). Nonetheless, the LLF of RRs significantly improved from 56.7 to 65.6 using the DLD system (p = 0.021) for DZ nodule detection. CONCLUSION: The performance of the DLD system was lower in the detection of DZ nodules compared to that of NDZ nodules. Nonetheless, RR performance in detecting DZ nodules improved upon using the DLD system. CRITICAL RELEVANCE STATEMENT: Despite the deep learning-based nodule detection system's limitations in detecting danger zone nodules, it proves beneficial for less-experienced observers by providing valuable assistance in identifying these nodules, thereby advancing nodule detection in clinical practice. KEY POINTS: • The deep learning-based nodule detection (DLD) system can improve the diagnostic performance of observers in nodule detection. • The DLD system shows poor diagnostic performance in detecting danger zone nodules. • For less-experienced observers, the DLD system is helpful in detecting danger zone nodules.

Differentiation of Vertebral Metastases From Focal Hematopoietic Marrow Depositions on MRI: Added Value of Proton Density Fat Fraction.

OBJECTIVE. The purpose of this study was to evaluate the added value of proton density fat fraction (PDFF) in differentiating vertebral metastases from focal hematopoietic marrow depositions. MATERIALS AND METHODS. The study included 44 patients with 30 vertebral metastases and 14 focal hematopoietic marrow depositions who underwent spinal MRI. The final diagnoses were based on histologic confirmation, follow-up MRI, or PET/CT. Two musculoskeletal radiologists with 1 and 15 years of experience independently interpreted both image sets (i.e., images from conventional MRI alone versus images from conventional MRI and PDFF combined). Using a 5-point scale, the readers scored their confidence in the malignancy of the vertebral lesions. The diagnostic performance (AUC) of the two image sets was assessed via ROC curve analyses. Sensitivities, specificities, and accuracies (for both image sets) were compared using the McNemar test. Kappa coefficients were calculated to assess interobserver agreement. RESULTS. Both readers showed improved diagnostic performance after PDFF was added (AUC, 0.840-0.912 and 0.805-0.895 for readers 1 and 2, respectively). However, adding PDFF did not significantly improve the sensitivity and specificity of either reader (p > .05). Interobserver agreement significantly improved from moderate (κ = 0.563) to excellent (κ = 0.947) after PDFF was added. CONCLUSION. The addition of PDFF to a conventional MRI protocol improved the diagnostic performance for differentiating vertebral metastases from focal hematopoietic marrow depositions but without resulting in significant improvement in sensitivity and specificity.

Fibrous adsorbent for removal of aqueous aromatic hydrocarbons.

Bundles of a strongly hydrophobic fibrous material (p-phenylene-2,6-benzobisoxazole; PBO; Zylon) were employed as an adsorbent for the removal of aqueous aromatic compounds, because the PBO fibers are too rigid to be woven and did not entrap suspended solids. The removal performance for nine kinds of polyaromatic hydrocarbons (PAHs) and di-(2-ethylhexyl) phthalate (DEHP) was evaluated. PAHs and DEHP at initial concentrations of 50 microg L(-1) were removed at 72.5-99.9% and ca. 95%, respectively, although the removal efficiencies were affected by the phase ratio (fiber weight/solution volume). The logarithm of the partition coefficient (log K) for planar PAHs was linearly correlated with the logarithm of the n-octanol/water partition coefficient (log P), but nonplanar PAHs, such as cis-stilbene, p-terphenyl, and o-terphenyl, showed significantly lower adsorption performance. The adsorbed PAHs were not desorbed effectively with CH3CN, CH2Cl2, and toluene. On the other hand, DEHP was effectively desorbed with methanol.

A spot test for ammonium ion by the color band formation method.

Removing nutrients from wastewaters is important in controlling eutrophication. Processes for removing nutrients require accurate control of operational conditions, and it is necessary to monitor nutrient concentrations during the removal process. For this purpose, a simple and accurate analytical method is especially important for small-scale wastewater treatment facilities. Here, we report a simple colorimetric method for determining NH(4)(+)-N in wastewater. The method is to detect NH(4)(+)-N by a color band length formed in a minicolumn, and similar methods for heavy metals detection were reported by Morosanova et al. In this study, the length of the color band of indonaphthol dye trapped on an adsorbent in a minicolumn was linearly correlated with NH(4)(+)-N concentration in the range 1-10mgNH(4)(+)-Nl(-1) under optimized conditions. This methods was developed on the basis of our previously reported color band methods for orthophosphate and nitrite determination, but the adsorbent used in this work consisted of an admixture of synthetic hydrotalcite particles and poly(vinyl chloride) particles coated with equal amounts of benzylcetyldimethylammonium chloride and biphenyl. When the method was applied to actual wastewaters, the results corresponded well with the results obtained by the standard method, and suspended solids (SS) and dissolved organic pollutants did not interfere with detection.

Visual determination of nitrite and nitrate in waters by color band formation method.

A spot test for aqueous nitrate and nitrite for controlling nitrogen removal performance in small-scale wastewater treatment facilities is proposed. In this method, NO(2)(-) ion in water samples was allowed to react with sulfanilic acid and 1-naphthol to form an anionic azo dye. The resulting colored solution was introduced onto a mini column (similar to a gas detecting tube) packed with PVC particles coated with benzyl cetyl dimethyl ammonium chloride (BCDMA) and biphenyl. The NO(2)(-)-N concentration was determined visually by measuring the color band length (CBL) in the column. The CBL correlates linearly with nitrite concentration in the 4-20 mg-N l(-1) range. The concentration of nitrite+nitrate was determined after reduction to nitrite with zinc. The concentration of NO(3)(-)-N species was calculated by difference. This method was used to visually determine the concentrations of NO(2)(-)-N and (NO(2)(-)+NO(3)(-))-N in domestic wastewater samples with maximum suspended solid (SS) and chemical oxygen demand (COD) concentrations of 114 mg l(-1) and 73.9 mg l(-1), respectively.

Phosphate removal and recovery with a synthetic hydrotalcite as an adsorbent.

Phosphate removal is important to control eutrophication and an ion exchange process is one of several treatment processes for this purpose. Hydrotalcite compounds (HTALs) are useful as adsorbents for phosphate removal because of their ion exchange properties. In this study, the adsorption properties of a granular synthetic HTAL for phosphate and the method of regeneration of the granular HTAL were examined. The adsorption isotherm of the granular HTAL was approximated by a modified Langmuir type, and the maximum adsorption capacity was 47.3 mg P g(-1), which corresponded to the content of HTAL in the granular one. Phosphate adsorbed on the HTAL was effectively desorbed with alkaline NaCl solutions and the HTAL was regenerated with 25 w/v% MgCl(2) solution. The regenerated HTAL could be reused repeatedly for the phosphate removal. Phosphate in the exhausted desorption solution was recovered as a precipitate of calcium phosphate by addition of CaCl(2), and the residual exhausted desorption solution could be also reused after supplying NaOH. The results suggest the possibility of an effective system for phosphate removal and recovery, which includes the following processes: adsorption, desorption, recovery of phosphate, and regeneration of the HTAL and the desorption solution.

Coupling of sequencing batch reactor and mesh filtration: operational parameters and wastewater treatment performance.

Wastewater treatment performance of the combined process of sequencing batch reactor (SBR) and mesh filtration bio-reactor was investigated with a synthetic wastewater. In this system, the filtration was performed only by the water level difference between the reactor and the effluent port, with the help of a sludge layer which accumulated on the mesh filter. A half volume of the mixed liquor was filtrated for ca. 1 h, and the filtration time was not affected by the initial pressure within the range of 0.5-2.0 m-H2O. Since the mesh filter could effectively reject the biomasses in the reactor, the effluents contained SS of less than 1 mg/L and BOD of less than 10 mg/L under continuous or intermittent aeration conditions. Nitrogen was also removed effectively with the adjustment of aeration time under the intermittent aeration conditions. The results obtained in this work indicate that mesh filtration could be effectively combined with SBR and improve the performance of SBR. In addition, it was shown that the performance of the mesh filtration such as filtration time and solids separation was influenced significantly by the saccharide content in the exocellular polymer of the activated sludge.

A spot test for aqueous phosphate by color band formation.

Phosphate is generally analyzed by color intensity of phosphoantimonylmolybdenum blue (PAMB): especially by a spot test based on spectrophotometric or visual determination. Visual determination is one of the simplest and most inexpensive methods; however, it is believed to be of low precision. In this work, we have developed an alternative phosphate spot test, where phosphate concentration is measured by the color band length of PAMB formed in a detection tube similar to a gas detection tube. The color band is formed by the entrapment of the hydrophobic ion pair of PAMB and quaternary ammonium ions in the column; we demonstrated that this color band length correlates quantitatively with the phosphate concentration. In order to optimize the measurement performance, systematic investigations have been carried out for various experimental parameters such as phosphate concentration, preparation conditions of the column packing material, the type of support material (either silica-gel or PVC), the solution feeding conditions (filtration or penetration), and volume of the sample solution. The effects from some co-existing components were also studied for the measurement of real samples. Determination of phosphate concentrations in actual wastewaters was successfully carried out by this method, indicating that the quantification range achievable was of 3-18 mg PO(4) L(-1) without dilution prior to the analysis. No interference was observed from suspended solid (SS) and organic pollutants (COD, TOC) during the wastewater analysis. Because of the simplicity and rapid processing of the samples (not requiring any special instruments) this newly developed method can be applied to the on-site analysis of wastewater.