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Sex and chronological age estimation are crucial in forensic investigations and research on individual identification. Although manual methods for sex and age estimation have been proposed, these processes are labor-intensive, time-consuming, and error-prone. The purpose of this study was to estimate sex and chronological age from panoramic radiographs automatically and robustly using a multi-task deep learning network (ForensicNet). ForensicNet consists of a backbone and both sex and age attention branches to learn anatomical context features of sex and chronological age from panoramic radiographs and enables the multi-task estimation of sex and chronological age in an end-to-end manner. To mitigate bias in the data distribution, our dataset was built using 13,200 images with 100 images for each sex and age range of 15–80 years. The ForensicNet with EfficientNet-B3 exhibited superior estimation performance with mean absolute errors of 2.93 ± 2.61 years and a coefficient of determination of 0.957 for chronological age, and achieved accuracy, specificity, and sensitivity values of 0.992, 0.993, and 0.990, respectively, for sex prediction. The network demonstrated that the proposed sex and age attention branches with a convolutional block attention module significantly improved the estimation performance for both sex and chronological age from panoramic radiographs of elderly patients. Consequently, we expect that ForensicNet will contribute to the automatic and accurate estimation of both sex and chronological age from panoramic radiographs. [ABSTRACT FROM AUTHOR]

The locus coeruleus (LC), our main source of norepinephrine (NE) in the brain, declines with age and is a potential epicentre of protein pathologies in neurodegenerative diseases (ND). In vivo measurements of LC integrity and function are potentially important biomarkers for healthy ageing and early ND onset. In the present study, high-resolution functional MRI (fMRI), a reversal reinforcement learning task, and dedicated post-processing approaches were used to visualise age differences in LC function (N = 50). Increased LC responses were observed during emotionally and task-related salient events, with subsequent accelerations and decelerations in reaction times, respectively, indicating context-specific adaptive engagement of the LC. Moreover, older adults exhibited increased LC activation compared to younger adults, indicating possible compensatory overactivation of a structurally declining LC in ageing. Our study shows that assessment of LC function is a promising biomarker of cognitive aging. Functional locus coeruleus (LC) imaging revealed that older adults exhibited increased LC activation compared to younger adults, indicating possible compensatory overactivation of a structurally declining LC in ageing. [ABSTRACT FROM AUTHOR]

Stroke is one of the major causes of death worldwide, and is closely associated with atherosclerosis of the carotid artery. Panoramic radiographs (PRs) are routinely used in dental practice, and can be used to visualize carotid artery calcification (CAC). The purpose of this study was to automatically and robustly classify and segment CACs with large variations in size, shape, and location, and those overlapping with anatomical structures based on deep learning analysis of PRs. We developed a cascaded deep learning network (CACSNet) consisting of classification and segmentation networks for CACs on PRs. This network was trained on ground truth data accurately determined with reference to CT images using the Tversky loss function with optimized weights by balancing between precision and recall. CACSNet with EfficientNet-B4 achieved an AUC of 0.996, accuracy of 0.985, sensitivity of 0.980, and specificity of 0.988 in classification for normal or abnormal PRs. Segmentation performances for CAC lesions were 0.595 for the Jaccard index, 0.722 for the Dice similarity coefficient, 0.749 for precision, and 0.756 for recall. Our network demonstrated superior classification performance to previous methods based on PRs, and had comparable segmentation performance to studies based on other imaging modalities. Therefore, CACSNet can be used for robust classification and segmentation of CAC lesions that are morphologically variable and overlap with surrounding structures over the entire posterior inferior region of the mandibular angle on PRs. [ABSTRACT FROM AUTHOR]

The bone mineral density (BMD) measurement is a direct method of estimating human bone mass for diagnosing osteoporosis, and performed to objectively evaluate bone quality before implant surgery in dental clinics. The objective of this study was to validate the accuracy and reliability of BMD measurements made using quantitative cone-beam CT (CBCT) image based on deep learning by applying the method to clinical data from actual patients. Datasets containing 7500 pairs of CT and CBCT axial slice images from 30 patients were used to train a previously developed deep-learning model (QCBCT-NET). We selected 36 volumes of interest in the CBCT images for each patient in the bone regions of potential implants sites on the maxilla and mandible. We compared the BMDs shown in the quantitative CBCT (QCBCT) images with those in the conventional CBCT (CAL_CBCT) images at the various bone sites of interest across the entire field of view (FOV) using the performance metrics of the MAE, RMSE, MAPE (mean absolute percentage error), R2 (coefficient of determination), and SEE (standard error of estimation). Compared with the ground truth (QCT) images, the accuracy of the BMD measurements from the QCBCT images showed an RMSE of 83.41 mg/cm3, MAE of 67.94 mg/cm3, and MAPE of 8.32% across all the bone sites of interest, whereas for the CAL_CBCT images, those values were 491.15 mg/cm3, 460.52 mg/cm3, and 54.29%, respectively. The linear regression between the QCBCT and QCT images showed a slope of 1.00 and a R2 of 0.85, whereas for the CAL_CBCT images, those values were 0.32 and 0.24, respectively. The overall SEE between the QCBCT images and QCT images was 81.06 mg/cm3, whereas the SEE for the CAL_CBCT images was 109.32 mg/cm3. The QCBCT images thus showed better accuracy, linearity, and uniformity than the CAL_CBCT images across the entire FOV. The BMD measurements from the quantitative CBCT images showed high accuracy, linearity, and uniformity regardless of the relative geometric positions of the bone in the potential implant site. When applied to actual patient CBCT images, the CBCT-based quantitative BMD measurement based on deep learning demonstrated high accuracy and reliability across the entire FOV. [ABSTRACT FROM AUTHOR]

The objective of this study was to automatically classify surgical plans for maxillary sinus floor augmentation in implant placement at the maxillary posterior edentulous region using a 3D distance-guided network on CBCT images. We applied a modified ABC classification method consisting of five surgical approaches for the deep learning model. The proposed deep learning model (SinusC-Net) consisted of two stages of detection and classification according to the modified classification method. In detection, five landmarks on CBCT images were automatically detected using a volumetric regression network; in classification, the CBCT images were automatically classified as to the five surgical approaches using a 3D distance-guided network. The mean MRE for landmark detection was 0.87 mm, and SDR for 2 mm or lower, 95.47%. The mean accuracy, sensitivity, specificity, and AUC for classification by the SinusC-Net were 0.97, 0.92, 0.98, and 0.95, respectively. The deep learning model using 3D distance-guidance demonstrated accurate detection of 3D anatomical landmarks, and automatic and accurate classification of surgical approaches for sinus floor augmentation in implant placement at the maxillary posterior edentulous region. [ABSTRACT FROM AUTHOR]

Objectives: The statistical shape model (SSM) is a model of geometric properties of a set of shapes based on statistical shape analysis. The SSM develops an average model of several objects using an automated algorithm that excludes the operator's subjectivity. The aim of this study was to develop a three-dimensional (3D) SSM of normal dentition to provide virtual templates for efficient treatment. Materials and methods: Dental casts were obtained from participants with normal dentition. After acquiring the 3D models, the SSMs of the individual teeth and whole dental arch were generated by an iterative closest point (ICP)-based rigid registration and point correspondences, respectively. Then, the individual tooth SSM was aligned to the whole dental arch SSM using ICP-based registration to generate an average model of normal dentition. Results: The generated 3D SSM showed specific morphological features of normal dentition similar to those previously reported. Moreover, on measuring the arch dimensions, all values in this study were similar to those previously reported using normal dentition. Conclusions: The 3D SSM of normal dentition may increase the diagnostic efficiency of orthodontic treatments by providing a visual objective. It can be also used as a 3D template in various fields of dentistry. Clinical relevance: Our SSM of normal dentition provides both quantitative and qualitative information on the 3D morphology of teeth and dental arches, which may provide valuable information on 3D virtual-setup, bracket fabrication, and aligner treatment. [ABSTRACT FROM AUTHOR]

The purpose of this study was to propose a continuity-aware contextual network (Canal-Net) for the automatic and robust 3D segmentation of the mandibular canal (MC) with high consistent accuracy throughout the entire MC volume in cone-beam CT (CBCT) images. The Canal-Net was designed based on a 3D U-Net with bidirectional convolutional long short-term memory (ConvLSTM) under a multi-task learning framework. Specifically, the Canal-Net learned the 3D anatomical context information of the MC by incorporating spatio-temporal features from ConvLSTM, and also the structural continuity of the overall MC volume under a multi-task learning framework using multi-planar projection losses complementally. The Canal-Net showed higher segmentation accuracies in 2D and 3D performance metrics (p < 0.05), and especially, a significant improvement in Dice similarity coefficient scores and mean curve distance (p < 0.05) throughout the entire MC volume compared to other popular deep learning networks. As a result, the Canal-Net achieved high consistent accuracy in 3D segmentations of the entire MC in spite of the areas of low visibility by the unclear and ambiguous cortical bone layer. Therefore, the Canal-Net demonstrated the automatic and robust 3D segmentation of the entire MC volume by improving structural continuity and boundary details of the MC in CBCT images. [ABSTRACT FROM AUTHOR]

Diagnosing osteosarcoma (OS) is very challenging and OS is often misdiagnosed as osteomyelitis (OM) due to the nonspecificity of its symptoms upon initial presentation. This study investigated the possibility of detecting OS-induced trabecular bone changes on panoramic radiographs and differentiating OS from OM by analyzing fractal dimensions (FDs) and degrees of anisotropy (DAs). Panoramic radiographs of patients with histopathologically proven OS and OM of the jaw were obtained. A total of 23 patients with OS and 40 patients with OM were enrolled. To investigate whether there was a microarchitectural difference between OS lesions and normal trabecular areas in each patient, two regions of interest (ROIs) were located on the CT images. Three microarchitectural parameters (box-counting FD, fast Fourier transform-based FD, and DA) were calculated. For both OS and OM, significant differences were found for all three microarchitectural parameters. Compared to normal trabecular bone, trabecular bone affected by OS and OM became isotropic and more complex. When comparing OS and OM, a statistically significant difference was found only in DA. Trabecular bones affected by OS became more isotropic than those affected by OM. Microarchitectural analysis, especially DA, could be useful for detecting OS-induced trabecular alterations and differentiating OS from OM. [ABSTRACT FROM AUTHOR]

Leaf spot (Pestalotiopsis microspora) is one of the major fungal diseases in blueberry (Vaccinium corymbosum L.) production and if not treated promptly that can eventually lead to plant death. To prevent and control leaf spot effectively, we selected BABA (beta-aminobutyric acid) as an inducer, "Canlan" in blueberries of rabbit eyes varieties as experimental material and then induced and inoculated leaf spot on blueberries as an experimental group and used uninduced blueberries inoculated with leaf spot as the control group. A transcriptome sequencing library was built, allowing identification of disease resistance and transcriptome analysis. The results showed that the resistance of blueberry to leaf spot was significantly increased after induction by BABA, which can increase the activity of the enzymes PPO, POD, PAL and and β-1,3-glucanase in blueberry leaves, inducing disease resistance of blueberries to leaf spot. Transcriptome sequencing results showed that there are 3953 genes participating in the processing of disease in KEGG metabolic pathways. Among the transcripts annotated to diseases, 1115 were involved in plant-pathogen interactions and 35 were involved in anthocyanin synthesis. Differential expression results showed that there were 900 upregulated differential genes and 531 downregulated differential genes, there were 70 genes highly expressed in the library. The results of Blast2PHI database revealed that among the genes related to leaf spot disease in blueberry, there were 727 transcription factors, 200 involved in disease prevention, 45 associated with cell circulation, effector proteins and 7 pathogenic genes controlling the biosynthesis of a-(1,3)-glucan. [ABSTRACT FROM AUTHOR]

The purpose of this study was to directly and quantitatively measure BMD from Cone-beam CT (CBCT) images by enhancing the linearity and uniformity of the bone intensities based on a hybrid deep-learning model (QCBCT-NET) of combining the generative adversarial network (Cycle-GAN) and U-Net, and to compare the bone images enhanced by the QCBCT-NET with those by Cycle-GAN and U-Net. We used two phantoms of human skulls encased in acrylic, one for the training and validation datasets, and the other for the test dataset. We proposed the QCBCT-NET consisting of Cycle-GAN with residual blocks and a multi-channel U-Net using paired training data of quantitative CT (QCT) and CBCT images. The BMD images produced by QCBCT-NET significantly outperformed the images produced by the Cycle-GAN or the U-Net in mean absolute difference (MAD), peak signal to noise ratio (PSNR), normalized cross-correlation (NCC), structural similarity (SSIM), and linearity when compared to the original QCT image. The QCBCT-NET improved the contrast of the bone images by reflecting the original BMD distribution of the QCT image locally using the Cycle-GAN, and also spatial uniformity of the bone images by globally suppressing image artifacts and noise using the two-channel U-Net. The QCBCT-NET substantially enhanced the linearity, uniformity, and contrast as well as the anatomical and quantitative accuracy of the bone images, and demonstrated more accuracy than the Cycle-GAN and the U-Net for quantitatively measuring BMD in CBCT. [ABSTRACT FROM AUTHOR]

The purpose of the retrospective study was to investigate the long-term result of implant-induced injury on the adjacent tooth. The subjects of this retrospective study were patients who had received implants and had tooth injury; direct invasion of root (group I), root surface contact (group II), or < 1 mm distance of the implant from the root (group III). Clinical and pathological changes were periodically examined using radiographs and intra-oral examinations. Paired t-tests and chi-square tests were used to evaluate the implant stability quotient (ISQ) of implant and tooth complications, respectively (α = 0.05). A total of 32 implants and teeth in 28 patients were observed for average 122.7 (± 31.7, minimum 86) months. Seven teeth, three of which were subsequently extracted, needed root canal treatment. Finally, 90.6% of the injured teeth remained functional. Complications were significant and varied according to the group, with group I showing higher events than the others. The ISQs increased significantly. One implant in group I resulted in osseointegration failure. The implant survival rate was 96.9%. In conclusion, it was found even when a tooth is injured by an implant, immediate extraction is unnecessary, and the osseointegration of the invading implant is also predictable. [ABSTRACT FROM AUTHOR]

We developed an automatic method for staging periodontitis on dental panoramic radiographs using the deep learning hybrid method. A novel hybrid framework was proposed to automatically detect and classify the periodontal bone loss of each individual tooth. The framework is a hybrid of deep learning architecture for detection and conventional CAD processing for classification. Deep learning was used to detect the radiographic bone level (or the CEJ level) as a simple structure for the whole jaw on panoramic radiographs. Next, the percentage rate analysis of the radiographic bone loss combined the tooth long-axis with the periodontal bone and CEJ levels. Using the percentage rate, we could automatically classify the periodontal bone loss. This classification was used for periodontitis staging according to the new criteria proposed at the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. The Pearson correlation coefficient of the automatic method with the diagnoses by radiologists was 0.73 overall for the whole jaw (p < 0.01), and the intraclass correlation value 0.91 overall for the whole jaw (p < 0.01). The novel hybrid framework that combined deep learning architecture and the conventional CAD approach demonstrated high accuracy and excellent reliability in the automatic diagnosis of periodontal bone loss and staging of periodontitis. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to examine whether dyslipidemia is associated with periodontitis according to age, sex, smoking, and harmful alcohol use in a representative sample of Korean adults who participated in the Sixth Korea National Health and Nutrition Examination Survey (KNHANES VI-3). Materials and methods: We examined 3987 subjects aged 19 to 79 years who participated in the KNHANES VI-3. Dyslipidemia was defined according to the definition proposed by the Korean Society of Lipidology and Atherosclerosis. The periodontal status of the patients was assessed using the community periodontal index. Multivariate logistic regression analysis was carried out and adjusted for sociodemographic variables, oral and general health behaviors, and oral health status. All analyses considered a complex sampling design, and multivariate analysis was performed in the age, sex, smoking, and harmful alcohol use subgroups. Results: Multivariate logistic regression analysis revealed significant associations between periodontitis and dyslipidemia including hypertriglyceridemia and hypo-high-density lipoprotein (HDL) cholesterolemia. In the subgroup analysis, periodontitis was significantly associated with hypo-HDL cholesterolemia in subjects older than 40 years, males, heavy smokers, and hazardous and harmful alcohol users. Moreover, periodontitis was significantly associated with hypercholesterolemia in hazardous and harmful alcohol users. Conclusions: The prevalence of periodontitis (CPI 3, 20.7%; CPI 4, 9.0%) was 29.7% in Korea. Hyper-TG and hypo-HDL-C were associated with periodontitis in all subjects. In the subgroup analysis, the association of periodontitis with hyper-TC and pre-hyper-TC was further confirmed in harmful alcohol users and males, respectively. Clinical relevance: This study reaffirmed that periodontitis is associated with dyslipidemia, especially with hyper-TG and hypo-HDL-C. As the association of periodontitis with hypo-HDL-C, hyper-TC, and pre-hyper-TC was found differently in subgroups according to age, gender, smoking, and alcohol drinking, researchers need to consider effect modifiers in further studies on the association between periodontitis and dyslipidemia. [ABSTRACT FROM AUTHOR]

NdNbO4−x MgO (x = 0.5, 1.0, 2.0, 3.0, 4.0) ceramics with high Q × ƒ values were prepared via the conventional solid-state reaction. The effects of MgO additive on the microstructures and microwave dielectric properties of NdNbO4 ceramics were investigated through various approaches. Microscopic analysis showed that the NdNbO4 phase and MgO phase were coexisted, and the crystal structure of the two phases did not changed with the additional amount of MgO. The dielectric constant could be explained by bulk density as a function of sintering temperature and satisfied with the Lichtenecker logarithmic superposition rule. The Q × ƒ value increased quickly when the phase composition changed from single phase to multiphase and was afterwards linked to the grain growth. The change in the temperature coefficient of resonant frequency was not large and was consistent with that in the dielectric constant. When x = 3.0, MgO additive effectively stepped up the Q × ƒ value of NdNbO4 to 1,35,000 GHz, which was fourfold of pure phase. [ABSTRACT FROM AUTHOR]

Pulmonary delivery of sildenafil for the treatment of pulmonary arterial hypertension could overcome the limitations of intravenous and oral administration routes, such as poor patient compliance and systemic side effects. In this study, a carrier-free dry powder inhaler (DPI) formulation was developed, using spray drying technique and L-leucine as a dispersibility enhancer. Sildenafil citrate salt and sildenafil free base were evaluated for drug transport using a Calu-3 cell model, and their suitability for DPI production by spray drying was tested. Characteristics of the resultant carrier-free DPI powders were examined, namely crystallinity, morphology, size distribution, density, zeta potential, and aerodynamic performance. A Box-Behnken design was adopted to optimize the formulation and process conditions, including leucine amount, fraction of methanol in spraying solvent, and inlet temperature. While both sildenafil forms exhibited sufficient permeability for lung absorption, only sildenafil base resulted in DPI powders which were stable for 6 months. The introduction of leucine into the formulations effectively enhanced aerodynamic performance of the powders and particles with favorable size, shape, and density were produced. The optimal DPI formulation determined from experimental design possesses excellent aerodynamic performance with 89.39% emitted dose and 80.08% fine particle fraction, indicating the possibility of incorporating sildenafil into carrier-free DPIs for pulmonary delivery. [ABSTRACT FROM AUTHOR]

Background: The prognosis of wide implants tends to be controversial. While wider implants were initially expected to result in a larger osseointegration area and have higher levels of primary stability, they were reported to have a relatively high rate of failure. The clinical outcome of ultrawide implants of more than 6 mm in diameter was evaluated through a retrospective study. Methods: The investigation was conducted on patients who had received ultrawide implant (≥6 mm diameter) placements in Seoul National University Bundang Hospital from January 2008 to December 2013. Complications were investigated during the maintenance period, and marginal bone loss was measured using periapical radiography. Primary stability immediately after the implant placement and second stability after second surgery or during impression were measured using Osstell Mentor (Osstell, Sweden) as an implant stability quotient (ISQ). Results: Fifty-eight implants were placed in 53 patients (30 male, 23 female), and they were observed for an average of 50.06 ± 23.49 months. The average ISQ value increased from 71.22 ± 10.26 to 77.48 ± 8.98 ( P < 0.005). The primary and secondary stability shows significantly higher at the mandible than at the maxilla ( P < 0.001). However, mean survival rate shows 98.28 %. Average marginal bone loss of 0.018 and 0.045 mm were measured at 12 and 24 months after the loading and 0.14 mm at final follow-up date (mean 46.25 months), respectively. Also in this study, the bone loss amount was noticeably small compared to regular implants reported in previous studies. Conclusions: The excellent clinical outcome of ultrawide implants was confirmed. It was determined that an ultrawide implant can be used as an alternative when the bone quality in the posterior teeth is relatively low or when a previous implant has failed. [ABSTRACT FROM AUTHOR]

This work was also supported by the Korea Medical Device Development Fund Grant funded by the Korean Government (The Ministry of Science and ICT, The Ministry of Trade, Industry, and Energy, The Ministry of Health & Welfare, and The Ministry of Food and Drug Safety) (Project Number: 1711174552, KMDF PR 20200901 0147 and Project Number: 1711174543, RS-2020-KD000011)." This work was also supported by a Seoul National University Research Grant in 2021." now reads: "This work was supported by a Seoul National University Research Grant in 2021. [Extracted from the article]

Familial gigantiform cementoma (FGC) is a rare autosomal dominant, benign fibro-cemento-osseous lesion of the jaws that can cause severe facial deformity. True FGC with familial history is extremely rare and there has been no literature regarding the radiological follow-up of FGC. We report a case of recurrent FGC in an Asian female child who has been under our observation for 6 years since she was 15 months old. After repeated recurrences and subsequent surgeries, the growth of the tumor had seemed to plateau on recent follow-up CT images. The transition from an enhancing soft tissue lesion to a homogeneous bony lesion on CT may indicate decreased growth potential of FGC. [ABSTRACT FROM AUTHOR]

A method for the synthesis of high quality indium-doped zinc oxide (In-doped ZnO) nanocrystals was developed using a one-step ester elimination reaction based on alcoholysis of metal carboxylate salts. The resulting nearly monodisperse nanocrystals are well-crystallized with typically crystal structure identical to that of wurtzite type of ZnO. Structural, optical, and elemental analyses on the products indicate the incorporation of indium into the host ZnO lattices. The individual nanocrystals with cubic structures were observed in the 5% In–ZnO reaction, due to the relatively high reactivity of indium precursors. Our study would provide further insights for the growth of doped oxide nanocrystals, and deepen the understanding of doping process in colloidal nanocrystal syntheses. [ABSTRACT FROM AUTHOR]

In order to robustly analyze the gait of Parkinson’s disease (PD) patients, a new gait phase discrimination method was developed for analyzing the three-axis accelerations of the ankle during walking. The magnitude of acceleration was compared with the lowpass-filtered signal of itself and pseudo foot-flat phases were determined. Four narrow windows were made sequentially and adaptively from the pseudo foot-flat phases. Each window contained a characteristic peak that discriminated the gait phases. From these windows, the initial contact (IC) point and end contact (EC) point were determined by finding the maximal point in the proximal–distal acceleration. Seven healthy individuals and 17 PD patients were subjected to a walking test on level ground for a distance of 6.5 m with the wearable activity monitoring system (W-AMS). Foot pressure and movement images were simultaneously recorded as references. The ICs and ECs detected by the proposed algorithm were compared with the manually marked events in the foot pressure signals. In healthy subjects, all the ICs and ECs were correctly detected. In the PD group, the detection accuracy was 97.6% for the ICs and 99.4% for the ECs. Based on these results, this novel method holds promise for use in monitoring temporal gait parameters continuously in PD patients, which will subsequently allow for the evaluation of motor fluctuations in PD patients. [ABSTRACT FROM AUTHOR]

A paucity of data exists to corroborate the few studies that report immune suppression after exposure to perfluorooctanesulfonate (PFOS). In this study, adult male C57BL/6 mice were exposed to PFOS daily via gavage for 60 days [0, 0.5, 5, 25, 50, or 125 mg/kg total administered dose (TAD)]. The results showed that liver mass was significantly increased at ≥5 mg PFOS/kg TAD and in a dose-dependent manner. Lymphocyte proliferation and natural killer cell activity were altered in male mice. Plaque forming cell (PFC) response was suppressed beginning at 5 mg/kg TAD. Based on the liver mass and PFC response, the no observed adverse effect level and lowest observed adverse effect level for male mice exposed PFOS for 60 days was 0.5 and 5 mg/kg TAD, respectively. Measured PFOS serum concentrations at these dose levels were 0.674 ± 0.166 and 7.132 ± 1.039 mg/l, respectively. These results indicate that PFOS exposure can affect the immunity function in mice at levels approximately 50-fold for highly exposed human populations. [ABSTRACT FROM AUTHOR]

Perfluorooctanesulfonate (PFOS) is a widespread contaminant in the environment, as well as in wildlife and in humans. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, there is little information about the effect of PFOS on immune system. In this study, adult male C57BL/6 mice were given by gavage 0, 5, 20 or 40 mg PFOS/kg day−1 for 7 days. The results showed that PFOS exposure decreased food intake and body weight and increased liver mass and serum corticosterone levels in a dose-dependent manner. Flow cytometry analysis showed that the number of lymphocytic subpopulation cells decreased significantly in 20 or 40 mg PFOS/kg day−1 group in comparison with normal C57BL/6 mice. Treatment with PFOS also markedly depressed the natural killer (NK) cell activity, lymphocyte proliferation and the plaque-forming cell (PFC) response. These results indicate that PFOS exposure can affect the immunity function in mice. [ABSTRACT FROM AUTHOR]

The no-wait flow shop scheduling that requires jobs to be processed without interruption between consecutive machines is a typical NP-hard combinatorial optimization problem, and represents an important area in production scheduling. This paper proposes an effective hybrid algorithm based on particle swarm optimization (PSO) for no-wait flow shop scheduling with the criterion to minimize the maximum completion time (makespan). In the algorithm, a novel encoding scheme based on random key representation is developed, and an efficient population initialization, an effective local search based on the Nawaz-Enscore-Ham (NEH) heuristic, as well as a local search based on simulated annealing (SA) with an adaptive meta-Lamarckian learning strategy are proposed and incorporated into PSO. Simulation results based on well-known benchmarks and comparisons with some existing algorithms demonstrate the effectiveness of the proposed hybrid algorithm. [ABSTRACT FROM AUTHOR]

Experiments were conducted to study the role of micro-electrolysis in removing chromaticity and COD and improving the biodegradability of pharmaceutical wastewater. The results showed that the use of micro-electrolysis technology could remove more than 90% of chromaticity and more than 50% of COD and greatly improved the biodegradability of pharmaceutical wastewater. Lower initial pH could be advantageous to the removal of chromaticity. A retention time of 30 minutes was recommended for the process design of microelectrolysis. [ABSTRACT FROM AUTHOR]

6-Arylamino-7-halo-5,8-quinolinediones ( 4a-4k, 5a-5b) were tested for in vitro cytotoxicity against human solid tumor cell lines such as A 549 (non-small cell lung), SK-OV-3 (ovarian), SK-MEL-2 (melanoma), HCT-15 (colon) and XF 498 (CNS) by SRB assay. The arylamino-7-chloro-5,8-quinolinediones 4 were also evaluated for cyclin-dependent kinase (CDK2 and CDK4) inhibitory effect. Among them, the 5,8-quinolinediones 4a and 5a with 7-(4-fluorophenyl)amino group were found to be potent cytotoxic against HCT 15, SKOV-3 and XF 498, and the compounds 4f and 4i showed inhibitory activities for the CDK4. [ABSTRACT FROM AUTHOR]

The work on metal organic chemical vapour deposition (MOCVD) and molecular beam epitaxy (MBE) in China dates from the early seventies. This paper reviews the recent progress of MOCVD and BME, including the equipment, technique and materials, such as IV, III-V and II-VI compound semiconductors, in a number of Institutes and Universities in China. The first part describes the design and construction of a fully automatic computer-controlled MOCVD equipment by Shanghai Institute of Metallurgy, Academia Sinica, preparation of SiGaAs/GaAlAs and GaInAs/InP superlattice, GaAs/GaAlAs heterojunction and quantum well structures and HgCdTe/CdTe/GaAs multilayer heterojunction materials and fabrication of photocathode, low noise MESFET and quantum well lasers. The second part reviews the development of MBE systems in China, preparation of GaAs/Si and CdTe/GaAs heterostructures, GaAlAs/GaAs quantum well, modulating heterostructures and superlattices and the fabrication of multiquantum well (MQW) heterojunction lasers and MQW F-P bistable operated logic devices. It can be seen that the MOCVD and MBE work in China is of a preliminary nature and only make a little contribution to the field of MOCVD and MBE semiconductors. [ABSTRACT FROM AUTHOR]

Panoramic radiography is the most commonly used equipment in the dental field, but there is no comprehensive standard about how to evaluate the spatial resolution of panoramic radiography. In this study, panorama resolution phantoms were developed for evaluation of horizontal and vertical resolution reflecting unique characteristics of panoramic radiography. Four horizontal resolution phantoms of staircase shape were designed to obtain images of horizontal lead line pairs in a 52 mm width. Four vertical resolution phantoms with vertical lead line pairs placed at an oblique angle were also designed. A phantom stand was made. Three machines were evaluated twice by two oromaxillofacial radiologists. The horizontal lead line pairs were readable over the entire measured area at the values of 1.88, 2.32, and 2.58 lp/mm for all machines. A readable area of horizontal 3.19 lp/mm was observed in the lingual side. In the vertical resolution phantoms, it was possible to read a narrower range. By using the panorama resolution phantoms and phantom stand, it was possible to evaluate the resolution of a wide buccolingual width in four significant areas. By evaluating the resolution of the vertical and horizontal compartments separately, it was possible to gain a better understanding of the obtained images. [ABSTRACT FROM AUTHOR]

Monte Carlo (MC) simulation is a simpler radiation dose assessment method than the conventional method, thermoluminescent dosimetry (TLD). MC simulation and TLD were compared as tools to evaluate the effective dose from paediatric panoramic radiography. Various exposure conditions and machine geometries were simulated using the MC method to investigate factors resulting in effective dose reduction. The effective dose of paediatric panoramic radiography was obtained using an MC simulation and its reliability was verified by a comparison with the value obtained using TLD. Next, 7 factors determining the effective dose in the MC simulation were input with 6 equally-spaced values, and a total of 36 simulations were performed to obtain effective dose values. The correlations between each dose-determining factor and the resulting effective dose were evaluated using linear regression analysis. The TLD-measured dose was 3.850 µSv, while the MC simulation yielded a dose of 3.474 µSv. Beam height was the factor that most strongly influenced the effective dose, while rotation angle and focus-to-patient distance were the least influential factors. MC simulation is comparable to TLD for obtaining effective dose values in paediatric panoramic radiography. Obtaining panoramic radiography with a short beam height can effectively reduce the dose in paediatric patients. [ABSTRACT FROM AUTHOR]

To study the relationship between ulcer recurrence and Helicobacter Pylori. 147 patients with peptic ulcer were divided into H. Pylori infected group and H. pylori uninfected group by rapid urease test serum antibody examination and histopathology of gastric biopsy specimens. We assigned all patients to receive dual oral therapy with omeprazole 40 mg/day for 4 weeks and amoxicillin 2000 mg/day for 2 weeks. To all patients, repeated gastroscope was performed at 8 weeks and one-year after beginning therapy to record whether the ulcer was cured. Endoscopic biopsy was also performed to determine H. pylori status. One year later, H. pylori positive patients had a higher ulcer recurrent rate than H. pylori negative patients (23. 33% vs 2. 70%; P=0.001). Ulcer recurrence was closely related to H. pylori infection. H. pylori was the risk factor for ulcer relapse. [ABSTRACT FROM AUTHOR]