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High sperm cryotolerance is crucial to the successful cryopreservation of boar sperm. Evaluating the cryotolerance of boar sperm by using a rapid and convenient technique can enhance the commercial viability of these sperm. This study investigated the correlation between sperm parameters for three sample subsets--fresh sperm, sperm with H2O2-induced oxidative damage (hereinafter referred to as H2O2-induced sperm), and frozen-thawed sperm--to identify the potential of these correlations to predict cryotolerance. A total of 64 sperm samples were obtained from 64 Duroc boars. The sperm parameters of the three subsets, where the frozen-thawed sperm were analysed at 30 or 180 min after thawing, were determined, and the coefficients of correlation between these parameters were calculated. The results indicated that H2O2-induced oxidative stress resulted in decreases in various sperm parameters--including total motility (TM), viability (VIA), mitochondrial membrane potential (MMP), and live sperm with MMP (LMP)--but increased their coefficients of variation. Receiver operating characteristic (ROC) curve analysis revealed that the kinematic parameters of the H2O2-induced sperm effectively predicted those of the frozen-thawed boar sperm at 30 min after thawing; the corresponding area under the ROC curve (AUC) was 0.8667 for TM and 0.8733 for progressive motility in the H2O2-induced sperm. For measurement at 180 min after thawing, the sperm membrane and mitochondrial parameters of the H2O2-induced sperm effectively predicted the LMP of the frozen-thawed boar sperm; the corresponding AUC was 0.8489 for VIA, 0.8289 for MMP, and 0.8444 for LMP. To our knowledge, this is the first study to directly establish a strong correlation between post-thaw boar sperm quality and H2O2-induced oxidative stress before freezing. Our proposed technique can serve as a valuable reference for the development of practical applications aimed at enhancing techniques for cryopreserving boar sperm. [ABSTRACT FROM AUTHOR]

Objectives: Oscillatory exercises using flexible poles, such as the Flexi-bar, were recommended as rehabilitation programs to increase trunk muscles strength; however, the strategy to enhance the training effects is under investigations. The aim of this study was to characterize the trunk movements and muscle activation patterns when performing an oscillation exercise with flexible poles in different weights. Methods: Twelve healthy male participants performed oscillation exercises with flexible poles of different weights. The center of mass, as well as surface electromyography for 10 trunk muscles were assessed while participants performed oscillation exercises. Results: The participants' trunks showed rhythmic anterior-posterior movement during oscillation exercises using flexible poles. The center-of-mass movement distances were 20.32 (6.73) mm, 25.33 (5.31) mm, 32.40 (9.94) mm, and 37.28 (21.59) mm for the Flexi-bar, light pole, medium pole, and heavy pole, respectively. Erector spinae, internal obliques, multifidus, and external obliques revealed significant activation levels during oscillation exercises. The participants who could perform steady and smooth oscillation with heavy pole for 30 seconds revealed phasic sequential muscle activation. Conclusion: The present study suggested that oscillation exercises with flexible poles were associated with a concomitant trunk movement in anterior-posterior direction and an effective activation of trunk muscles. [ABSTRACT FROM AUTHOR]

It is assessed in detail both experimentally and theoretically how the interlayer coupling of transition metal dichalcogenides controls the electronic properties of the respective devices. Gated transition metal dichalcogenide structures show electrons and holes to either localize in individual monolayers, or delocalize beyond multiple layers--depending on the balance between spin-orbit interaction and interlayer hopping. This balance depends on the layer thickness, momentum space symmetry points, and applied gate fields. The design range of this balance, the effective Fermi levels, and all relevant effective masses is analyzed in great detail. A good quantitative agreement of predictions and measurements of the quantum confined Stark effect in gated MoS2 systems unveils intralayer excitons as the major source for the observed photoluminescence. [ABSTRACT FROM AUTHOR]

The diagnosis of primary hepatocellular carcinoma (HCC) in high risk patients, such as those with chronic hepatitis B or C with/without cirrhosis of the liver, can be made with relevant image studies alone; however, morphologic confirmation by cytology or histopathology is essential to the diagnosis of metastatic HCC because the treatment of the latter differs from that of primary extrahepatic malignancy. Although both cytology and histopathology are important tools in the diagnosis of malignancy, histopathology almost always plays a confirmatory and pivotal role, and also a gold standard in cyto-histological correlation. We present two patients of metastatic HCC to rare sites; endobronchus in one, and neck lymph nodes, face and the abdominal wall in the other. Repeated bronchial biopsy in the first patient and excisional biopsy from the metastatic sites of the second patient failed to make a conclusive diagnosis of metastatic HCC. However, bronchial brushing in the first patient and fine needle aspiration cytology from the respective metastatic sites of the second patient consistently showed characteristic HCC features and provided clinicians with the rationale for ongoing treatment. The diagnostic issues and possible pitfalls are discussed. Cytology and histopathology appear equipollent; sometimes cytology can play a diagnostic role when histopathology fails its expected role in this scenario. [ABSTRACT FROM AUTHOR]

Objective Opioids are frequently used in spine surgeries despite their adverse effects, including physical dependence and addiction. Gender difference is an important consideration for personalized treatment. There is no review assessing the prevalence of opioid use between men and women before spine surgeries. Design We compared the prevalence of preoperative opioid use between men and women. Setting Spine surgery. Subjects Comparison between men and women. Methods PubMed, Embase, and Cochrane were searched from inception to November 9, 2018. Clinical characteristics and prevalence of preoperative opioid use were collected. Where feasible, data were pooled from nonoverlapping studies using random-effects models. Results Four studies with nonoverlapping populations were included in the meta-analysis (one prospective, three retrospective cohorts). The prevalence of preoperative opioid use was 0.64 (95% CI = 0.40–0.83). Comparing men with women, no statistically significant difference in preoperative opioid use was detected (relative risk [RR] = 0.99, 95% CI = 0.96–1.02). Surgery location (cervical, lumbar) and study duration (more than five years or five years or less) did not modify this association. All involved open spine surgery. Only one secondary analysis provided data on both pre- and postoperative opioid use stratified by gender, which showed a borderline significantly higher prevalence of postoperative use in women than men. Conclusions The prevalence of opioid use before spine surgery was similar between men and women, irrespective of surgery location or study duration. More studies characterizing the pattern of opioid use between genders are still needed. [ABSTRACT FROM AUTHOR]

This study investigated the effectiveness of a 20-week Simulated Developmental Horse-Riding Program (SDHRP) by using an innovative exercise equipment (Joba®) on the motor proficiency and sensory integrative functions in 60 children with autism (age: 6 years, 5 months to 8 years, 9 months). In the first phase of 20 weeks, 30 children received the SDHRP in addition to their regular occupational therapy while another 30 children received regular occupational therapy only. The arrangement was reversed in the second phase of another 20 weeks. Children with autism in this study showed improved motor proficiency and sensory integrative functions after 20-week SDHRP (p < .01). In addition, the therapeutic effect appeared to be sustained for at least 24 weeks (6 months). [ABSTRACT FROM AUTHOR]

Century eggs (also known as pídàn) are a widely used preserved food product in Taiwanese cuisine. Due to their peculiar appearance, pungent odor, and unusual texture, several consumers have raised concerns. Actually, some metallic additives are employed to control the quality of gelation of protein during the production of century eggs. Therefore, a method involving microwave plasma-atomic emission spectrometer and microwave-assisted digestion was proposed in this study. In addition, to clarify distribution information of metallic additives in century eggs, detailed analyses based on the egg structure were adopted. The linearities for Fe and Zn were obtained in the range of 0.1-5, and 0.02-1 mg L-1 for Cu and Pb. The method detection limits for test metals were 0.06-0.036 mg L-1. The measured values for the RM EGGS-1 sample agreed reasonably well with the reference values, demonstrating that the developed method is practical for routine analysis with lower instrument procurement/running cost. The analytical results for century eggs collected from local markets revealed diverse distributions of metal ions in different parts. Remarkably, this method can readily identify the metallic additives used during the production processes even in the presence of complicated matrices. [ABSTRACT FROM AUTHOR]

Background and Aim: Esophageal squamous cell neoplasia (ESCN) is predominant in Asia. Endoscopic mucosal resection and endoscopic submucosal dissection (ESD) have both been recommended worldwide, however the application of endoscopic radiofrequency ablation (RFA) for treatment of early superficial ESCN remains inconclusive. We conducted a meta-analysis to study the effectiveness of RFA for early superficial ESCN. Methods: Three major bibliographic databases were reviewed for the enrollment of case series and cohort trials prior to August 23, 2023. We included adults diagnosed with early superficial ESCN who had been receiving endoscopic RFA or ESD if the treatments were available. Our focus was on the 12-month histological complete response rate (CR) and 3-month histological CR, as well as the acute and late postoperative adverse events (AEs) rate during the at follow-up periods. Results: Nine studies were enrolled for qualitative synthesis of narrative review, with eight trials involving a total of 447 participants for analysis. The pooled 12-month and 3-month histological CR were 0.83 (95% CI, 0.59–0.94, I2 = 80%) and 0.74 (95% CI, 0.67–0.80, I2 = 0%), respectively. As for safety, the acute and late postoperative AEs were 0.11 (95% CI, 0.05–0.26, I2 = 68%) and 0.19 (95% CI, 0.14–0.26, I2 = 0%), respectively. In subgroup analysis, the incidence of bleeding, laceration and perforation after endoscopic RFA showed 0.06, 0.06 and 0.02, respectively. When compared with ESD, RFA showed lower acute AEs and late AEs without any obvious significance. Conclusions: For early superficial ESCN, endoscopic RFA achieved both higher 12-month complete remission and late complication postoperatively when compared to 3-month histological CR and acute AEs separately, while the stricture was encountered most commonly. The choice between endoscopic RFA and ESD remains inconclusive. [ABSTRACT FROM AUTHOR]

Background: Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable indolent growth with malignant potential and late recurrence. Approximately 95% are of adult type. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult granulosa cell tumor. Our previous case report showed that unique FOXL2 402C > G mutation and defective DNA mismatch repair system are associated with the development of adult granulosa cell tumor. Findings: In this study, the DNA sequences of four genes, MSH2, MLH1, MSH6, and PMS2, in the DNA mismatch repair system were determined via direct sequencing to elucidate the exact mechanism for the development of this granulosa cell tumor. The results showed that two missense germline mutations, T485K and N775L, inactivate the PMS2 gene. Conclusions: The results of this case study indicated that although FOXL2 402C > G mutation determines the development of granulosa cell tumor, PMS2 mutation may be the initial driver of carcinogenesis. Immunohistochemistry-based tumor testing for mismatch repair gene expression may be necessary for granulosa cell tumors to determine their malignant potential or if they are part of Lynch syndrome. [ABSTRACT FROM AUTHOR]

Background: Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to 15% of cases and multiple cystic teratomas may be present in one ovary. The aim of this study is to clarify if development of mature cystic teratomas of the ovaries in a single host is metachronous or due to autoimplant or recurrence. Case presentation: We report a woman with bilateral mature cystic teratomas of the ovaries. DNA profiles of these teratomas were investigated via short tandem repeat (STR) analysis and methylation statuses were determined via methylation sensitive multiplex ligation-dependent probe amplification methods. The results showed that the cystic teratomas originated from different stages of oogonia or primary oocyte before germinal vesicle stage failure of meiosis I in female gametogenesis. Potentially relevant literature was searched in PubMed database. Cases of bilateral or multiple mature cystic teratomas of the ovaries were analyzed. To date, there has been no reported case of multiple mature cystic teratomas in which clarification of the origin was achieved using molecular genetic methods. Conclusions: The results of this case study provide evidence of metachronous development of mature cystic teratomas of the ovaries and may serve as a reference in the management of patients following laparoscopic cystectomy. [ABSTRACT FROM AUTHOR]

This paper studies the problem of optimal aircraft takeoff and landing sequencing at congested airports. The objective is to minimize the makespan for all the aircraft to land at or depart from the airport. This paper presents a novel approach to deal with aircraft separation constraints. The separation time is considered as the combination of the turbulence generated by the preceding aircraft and the ability of the succeeding aircraft to resist turbulence. With this novel concept, the separation constraints are more flexible with aircraft types and are linear with the decision variables. When the sequencing matrix is used as the decision variable, the required number of separation constraints grows linearly with the number of aircraft instead of the quadratic growth with existing formulations. The current formulation also considers the problem of minimizing the deviation from scheduled arriving and departing times. The result provides the speed advisories for each aircraft to air traffic controllers. With the current optimization process, the final result can meet both optimal sequence and minimal time variation requirements. Finally, several simulation results are used to demonstrate the effectiveness of this approach. [ABSTRACT FROM AUTHOR]

This paper describes the design and fabrication of a "pop-up" electrochemical paper-based analytical device (pop-up-EPAD) to measure beta-hydroxybutyrate (BHB)--a biomarker for diabetic ketoacidosis--using a commercial combination BHB/glucometer. Pop-up-EPADs are inspired by pop-up greeting cards and children's books. They are made from a single sheet of paper folded into a three-dimensional (3D) device that changes shape, and fluidic and electrical connectivity, by simply folding and unfolding the structure. The reconfigurable 3D structure makes it possible to change the fluidic path and to control timing; it also provides mechanical support for the folded and unfolded structures that enables good registration and repeatability on folding. A pop-up-EPAD designed to detect BHB shows performance comparable to commercially available plastic test strips over the clinically relevant range of BHB in blood when used with a commercial glucometer that integrates the ability to measure glucose and BHB (combination BHB/glucometer). With simple modifications of the electrode and the design of the fluidic path, the pop-up-EPAD also detects BHB in buffer using a simple glucometer--a device that is more available than the combination BHB/glucometer. Strategies that use a "3D pop-up"--that is, large-scale changes in 3D structure and fluidic paths--by folding/unfolding add functionality to EPADs (e.g., controlled timing, fluidic handling and path programming, control over complex sequences of steps, and alterations in electrical connectivity) and should enable the development of new classes of paper-based diagnostic devices. [ABSTRACT FROM AUTHOR]

Background: Endoscopic band ligation (EBL) and radiofrequency ablation (RFA) have emerged as alternative therapies of gastric antral vascular ectasia (GAVE) in addition to endoscopic thermal therapy (ETT), but the optimum choice remains inconclusive. Aim: We conducted a meta-analysis in order to compare these three treatments for GAVE. Methods: We searched the electronic databases of PubMed, Embase and Cochrane Central Register of Controlled Trials without any language restrictions and also performed a manual literature search of bibliographies located in both retrieved articles and published reviews for eligible publications prior to December 8, 2021. We included comparative trials which had evaluated the efficacy and safety of interventions in adults (aged ≥ 18 years) diagnosed with symptomatic GAVE and was confirmed according to clinical backgrounds and upper gastrointestinal endoscopy. We included reports that compared three interventions, ETT, EBL, and RFA. The study was comprised of adults diagnosed with GAVE and focused on overall mortality, bleeding cessation, endoscopic improvement, complications, hospitalization, hemoglobin improvement, number of sessions and transfusion requirements. Results: Twelve studies were performed involving a total of 571 participants for analysis. When compared with ETT, EBL achieved better bleeding cessation (OR 4.48, 95% CI 1.36–14.77, p = 0.01), higher hemoglobin improvement (MD 0.57, 95% CI 0.31–0.83, p < 0.01) and lower number of sessions (MD − 1.44, 95% CI − 2.54 to − 0.34, p = 0.01). Additionally, EBL was superior to ETT in endoscopic improvement (OR 6.00, 95% CI 2.26–15.97, p < 0.01), hospitalization (MD − 1.32, 95% CI − 1.91 to − 0.74, p < 0.01) and transfusion requirement (MD − 2.66, 95% CI − 4.67 to − 0.65, p = 0.01) with statistical significance, with the exception of mortality (OR 0.58, 95% CI 0.19–1.77, p = 0.34) and complication rate (OR 5.33, 95% CI 0.58–48.84, p = 0.14). Conclusion: For GAVE, we suggest that EBL be initially recommended, and APC and RFA be used as alternative treatment choices based upon a very low quality of evidence. [ABSTRACT FROM AUTHOR]

Background: Cycling hypoxia is a well-recognized phenomenon within animal and human solid tumors. It contributes to the resistance to cytotoxic therapies through anti-apoptotic effects. However, the mechanism underlying cycling hypoxia-mediated anti-apoptosis remains unclear.Methods: Reactive oxygen species (ROS) production, activation of the hypoxia-inducible factor-1 alpha (HIF-1α) and nuclear factor-κB (NF-κB) signaling pathways, B-cell lymphoma extra-long (Bcl-xL) expression, caspase activation, and apoptosis in in vitro hypoxic stress-treated glioblastoma cells or tumor hypoxic cells derived from human glioblastoma xenografts were determined by in vitro ROS analysis, reporter assay, western blotting analysis, quantitative real-time PCR, caspase-3 activity assay, and annexin V staining assay, respectively. Tempol, a membrane-permeable radical scavenger, Bcl-xL knockdown, and specific inhibitors of HIF-1α and NF-κB were utilized to explore the mechanisms of cycling hypoxia-mediated resistance to temozolomide (TMZ) in vitro and in vivo and to identify potential therapeutic targets.Results: Bcl-xL expression and anti-apoptotic effects were upregulated under cycling hypoxia in glioblastoma cells concomitantly with decreased responses to TMZ through ROS-mediated HIF-1α and NF-κB activation. Tempol, YC-1 (HIF-1 inhibitor), and Bay 11-7082 (NF-κB inhibitor) suppressed the cycling hypoxia-mediated Bcl-xL induction in vitro and in vivo. Bcl-xL knockdown and Tempol treatment inhibited cycling hypoxia-induced chemoresistance. Moreover, Tempol treatment of intracerebral glioblastoma-bearing mice combined with TMZ chemotherapy synergistically suppressed tumor growth and increased survival rate.Conclusions: Cycling hypoxia-induced Bcl-xL expression via ROS-mediated HIF-1α and NF-κB activation plays an important role in the tumor microenvironment-promoted anti-apoptosis and chemoresistance in glioblastoma. Thus, ROS blockage may be an attractive therapeutic strategy for tumor microenvironment-induced chemoresistance. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the extensive invasion of tumor cells into normal brain tissue, a life-threatening feature of malignant gliomas. How invasive tumor cells migrate into normal brain tissue and form a secondary tumor structure remains to be elucidated. In the present study, the morphological and phenotypic changes of glioma cells during invasion in a C6 glioma model were investigated. C6 glioma cells were stereotactically injected into the right putamen region of adult Sprague-Dawley rats. The brain tissue sections were then subjected to hematoxylin and eosin, immunohistochemical or immunofluorescent staining. High magnification views of the tissue sections revealed that C6 cells formed tumor spheroids following implantation and marked invasion was observed shortly after spheroid formation. In the later stages of invasion, certain tumor cells invaded the perivascular space and formed small tumor clusters. These small tumor clusters exhibited certain common features, including tumor cell multilayers surrounding an arteriole, which occurred up to several millimeters away from the primary tumor mass; a high proliferation rate; and similar gene expression profiles to the primary tumor. In conclusion, the present study revealed that invading tumor cells are capable of forming highly proliferative cell clusters along arterioles near the tumor margin, which may be a possible cause of the recurrence of malignant glioma. [ABSTRACT FROM AUTHOR]

Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable late recurrent and malignant behavior. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult-type granulosa cell tumor. In this study, we report an 80-year-old woman with a granulosa cell tumor arising from ovary. She presented with a huge pelvic mass with postmenopausal bleeding. No obvious intraperitoneal tumor implants were observed during operation. Final diagnosis was granulosa-theca cell tumor without capsule invasion. No recurrent disease was noted during 3-year post-operation follow-up period. Molecular studies showed a heterozygous FOXL2 402C > G mutation in the tumor by direct gene sequencing. In addition, DNA replication error, on analysis of the lengths of CAG repeats in androgen receptor gene, revealed defective DNA mismatch repair system in the granulosa cell tumor. We propose that the 402C > G mutation in FOXL2 is critical to the development of adult granulosa cell tumor. However, the malignant behavior of this tumor is driven by DNA mismatch repair deficiency. Unequal DNA copy numbers were noted on array comparative genomic hybridization. This implies that there is malignant potential even in the early stage of the granulosa cell tumor. Late malignant recurrence may be a late event of DNA repair function disability, not directly related to pathognomonic FOXL2 mutation. [ABSTRACT FROM AUTHOR]

Background: Renal cell carcinoma, a common malignant tumor arising from the kidney, occurs in 3.62 and 1.95 cases per one hundred thousand people among men and women, respectively, in Taiwan each year. Approximately 80% of cases are classified as clear-cell renal cell carcinoma. Inactivation of the von Hippel-Lindau tumor suppressor gene has been implicated in the tumorigenic pathway of renal cell carcinoma. Two single nucleotide polymorphisms, rs779805 and rs1642742, located in the promoter and 3′ untranslated regions of the von Hippel-Lindau gene are informative and implicated in the occurrence of renal cell carcinoma worldwide. The aim of this study is to clarify whether these polymorphisms are associated with renal cell carcinoma in Taiwanese. Genomic DNA was isolated from normal and tumor tissues of 19 renal cell carcinoma patients. The samples were screened for allelic polymorphisms by restriction fragment length polymorphism with BsaJ I and Acc I digestion. Reconfirmation was carried out by direct sequencing. Results: Consistent with Knudson's two-hit theory, AA to AG somatic mutations were observed in rs779805. In addition, loss of heterozygosity in both rs779805 and rs1642742 was demonstrated in 10 out of 15 RCC patients aged 50 or over. The G allele or AG heterozygote frequencies at these two loci were much higher in patient germline DNA when compared with the control group. After adjusting for age, the frequency of the G allele in both loci was much higher for late onset renal cell carcinoma in the Taiwanese population. Conclusions: Our current results confirmed that the existence of G allele in both rs779805 and rs1642742 in the von Hippel-Lindau tumor suppressor gene is of importance in renal cell carcinoma tumorigenesis. However, more comprehensive and detailed research is needed to address the clinical relevance. Larger sample size is required to determine the exact power of correlation between these two genetic polymorphisms and renal cell carcinoma. [ABSTRACT FROM AUTHOR]

In a wireless sensor network (WSN), a great number of sensor nodes are deployed to gather sensed data. These sensor nodes are typically powered by batteries so their energy is restricted. Sensor nodes mainly consume energy in data transmission, especially over a long distance. Since the location of the base station (BS) is remote, the energy consumed by each node to directly transmit its data to the BS is considerable and the node will die very soon. A well-designed routing protocol is thus essential to reduce the energy consumption. In this paper, we propose a Cycle-Based Data Aggregation Scheme (CBDAS) for grid-based WSNs. In CBDAS, the whole sensor field is divided into a grid of cells, each with a head. We prolong the network lifetime by linking all cell heads together to form a cyclic chain so that the gathered data can move in two directions. For data gathering in each round, the gathered data moves from node to node along the chain, getting aggregated. Finally, a designated cell head, the cycle leader, directly transmits to the BS. CBDAS performs data aggregation at every cell head so as to substantially reduce the amount of data that must be transmitted to the BS. Only cell heads need disseminate data so that the number of data transmissions is greatly diminished. Sensor nodes of each cell take turns as the cell head, and all cell heads on the cyclic chain also take turns being cycle leader. The energy depletion is evenly distributed so that the nodes' lifetime is extended. As a result, the lifetime of the whole sensor network is extended. Simulation results show that CBDAS outperforms protocols like Direct, PEGASIS, and PBDAS. [ABSTRACT FROM AUTHOR]

This research work concerns the preparation of a bi-layer antifogging (AF) coating on a polycarbonate plastic substrate. The bottom layer, serving as a mechanical support, is an organic-inorganic composite that is formed by embedding colloidal silica in a crosslinked network of γ-glycidoxypropyltrimethoxysiline. Atop this layer, a coating formulation incorporating glycidyl methacrylate and poly(ethylene oxide)-based hydrophilic species was applied and then UV-cured to yield a film exhibiting the AF effect. Solid-state 29Si-NMR and FTIR were employed to investigate the evolution of chemical bonds during the sol-gel and the UV-curing processes. Contact angles of water on the coatings were measured to examine the hydrophilicity of the coatings. Furthermore, industrial tests such as pencil hardness, tape adhesion, and steam tests were carried out to evaluate the performance of the coatings. [ABSTRACT FROM AUTHOR]

We investigated the relationships among teacher support, peer conflict resolution, and emotional experiences at school in 2,782 students from 12 secondary schools in Shanghai, China. The results demonstrated that: a) most of the students had positive perceptions of teacher support, effective peer conflict resolution, happiness, and communication satisfaction in school context; b) males used more negative peer conflict resolution strategies than did females; c) in all school experiences, significant differences were found between students in different grade levels; and d) teacher support was found to have a positive influence on student happiness, satisfaction, and peer conflict resolution, and effective peer conflict resolution also had a positive influence on student happiness and satisfaction, but negative emotion was found to reduce happiness and satisfaction. [ABSTRACT FROM AUTHOR]

This paper applies a matrix-analytical approach to analyze the temporal behavior of Markovian-modulated batch-service queue with discrete-time batch Markovian arrival process (DBMAP). The service process is correlated and its structure is presented through discrete-time batch Markovian service process (DBMSP). We examine the temporal behavior of packet loss by means of conditional statistics with respect to congested and noncongested periods that occur in an alternating manner. The congested period corresponds to having more than a certain number of packets in the buffer; noncongested period corresponds to the opposite. All of the four related performance measures are derived, including probability distributions of a congested and noncongested periods, the probability that the system stays in a congested period, the packet loss probability during congested period, and the long term packet loss probability. Queueing systems of this type arise in the domain of wireless communications. [ABSTRACT FROM AUTHOR]

Shift work disrupts the sleep-wake cycle, leading to sleepiness, fatigue, and performance impairment, with implications for occupational health and safety. For example, aircraft maintenance crew work a 24-hour shift rotation under the job stress of sustaining the flight punctuality rate. If an error occurs during the aircraft maintenance process, this error may become a potential risk factor for flight safety. This paper focuses on optimal work shift scheduling to reduce the fatigue of shift workers. We proposed a conditional exponential mathematical model to represent the fatigue variation of workers. The fatigue model is integrated with the work shift scheduling problem with considerations of workers' preferences of days off, company or government regulations, and man power requirements. The combined problem is formulated as a mixed-integer program, in which the shift assignments are described by binary variables. Using the proposed method, we can find a feasible work shift schedule and also have a schedule that minimizes the peak fatigue of shift workers while satisfying their days off demands. Several examples are provided to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Fleet assignment is one of the four major steps in airline planning. The objective of the fleet assignment problem (FAP) is to determine which type of aircraft should fly on each flight leg while considering different characteristics and costs associated with different fleet types. This article proposes a multiphase approach to solving the FAP. Backward arcs were used to solve basic FAPs. Then the backward arcs were eliminated by using linear programming. By allowing backward time, our formulation has a similar level of flexibility as the fleet assignment model with time-window (FAMTW), but the problem size grows much slower than FAMTW. Examples using real data obtained from a major airline are included in this article. [ABSTRACT FROM AUTHOR]

Background: Obesity among young children in Hong Kong has become a public health problem. This study explored associations between Chinese parent reported children's quality of life (QoL), socio-demographics and young children's weight status from 27 preschool settings. Methods: A mixed-method approach, including quantitative and qualitative tools, was employed for this cross-sectional study. Quantitative data were collected from 336 Chinese parents of children aged 2-7 years. Paediatric Quality of Life Inventory 4.0 (PedsQL, v 4.0) and a questionnaire about parents' socio-demographics were used. In-depth interviews with mothers, teachers and children from a larger sample were the basis of 10 case studies. Quantitative data were analysed using chi-square analysis, one-way ANOVA and logistic regression. Qualitative data were analysed according to a multi-level framework that established linkages with quantitative data. Results: The children's Body Mass Index (BMI) ranged from 11.3 to 28.0 kg/m2 and was classified into four weight groups. ANOVAs showed that the normal-weight children had significantly higher PedsQL scores in Physical Functioning than obese children (mean difference = 14.19, p < .0083) and significantly higher scores in School Functioning than overweight children (mean difference = 10.15, p < .0083). Results of logistic regression showed that relative to normal-weight children, obese children had a 2-5 times higher odds of showing problems in Physical, Social Functioning and School Performance. Overweight children had 2 times higher odds of problems in Social Functioning, and underweight children had a 2 times higher odds of problems in Physical Functioning. Children's age (χ2 = 21.71, df = 3, p < 0.01), and housing (χ2 = 33.00, df = 9, p < 0.01) were associated with their weight. The case studies further act as a supplement to the quantitative data that children showed emotional problems across different abnormal weight statues; and the association between children's weight status and well-being might be affected by multiple childcare arrangements and familial immigration status. Conclusions: This study is one of only a few studies that have examined parents', teachers' and young children's own perceptions of the children's quality of life across different weight statuses. The results are discussed in terms of their implications for intervention. [ABSTRACT FROM AUTHOR]

Background: Dimethyl sulfoxide (DMSO) is an amphipathic molecule that displays a diversity of antitumor activities. Previous studies have demonstrated that DMSO can modulate AP-1 activity and lead to cell cycle arrest at the G1 phase. HLJ1 is a newly identified tumor and invasion suppressor that inhibits tumorigenesis and cancer metastasis. Its transcriptional activity is regulated by the transcription factor AP-1. However, the effects of DMSO on HLJ1 are still unknown. In the present study, we investigate the antitumor effects of DMSO through HLJ1 induction and demonstrate the mechanisms involved. Methods and Findings: Low-HLJ1-expressing highly invasive CL1-5 lung adenocarcinoma cells were treated with various concentrations of DMSO. We found that DMSO can significantly inhibit cancer cell invasion, migration, proliferation, and colony formation capabilities through upregulation of HLJ1 in a concentration-dependent manner, whereas ethanol has no effect. In addition, the HLJ1 promoter and enhancer reporter assay revealed that DMSO transcriptionally upregulates HLJ1 expression through an AP-1 site within the HLJ1 enhancer. The AP-1 subfamily members JunD and JunB were significantly upregulated by DMSO in a concentration-dependent manner. Furthermore, pretreatment with DMSO led to a significant increase in the percentage of UV-induced apoptotic cells. Conclusions: Our results suggest that DMSO may be an important stimulator of the tumor suppressor protein HLJ1 through AP-1 activation in highly invasive lung adenocarcinoma cells. Targeted induction of HLJ1 represents a promising approach for cancer therapy, which also implied that DMSO may serve as a potential lead compound or coordinated ligand for the development of novel anticancer drugs. [ABSTRACT FROM AUTHOR]

This study proposes a flow model using a modified Lighthill-Whitham-Richards highway model. The proposed model treats each aircraft on an airway as a continuous distribution of air collision probability, which is called the danger value distribution. With the proposed flow model, collision can be easily predicted by the peak value of the overlap of the danger value distribution of each aircraft. The study further proposes a velocity adjustment method that can be used to resolve the conflict. The proposed method can be applied for aircraft separation during the landing process, in which the separation time is different for different combinations of aircraft types. [ABSTRACT FROM AUTHOR]

Background and aim: The DNA repair gene Ku70, an important member of non-homologous end-joining repair system, is thought to play an important role in the repairing of DNA double strand breaks. It is known that defects in double strand break repair capacity can lead to irreversible genomic instability. However, the polymorphic variants of Ku70, have never been reported about their association with gastric cancer susceptibility. Methods: In this hospital-based case-control study, the associations of Ku70 promoter T-991C (rs5751129), promoter G-57C (rs2267437), promoter A-31G (rs132770), and intron 3 (rs132774) polymorphisms with gastric cancer risk in a Taiwanese population were investigated. In total, 136 patients with gastric cancer and 560 age- and gender-matched healthy controls recruited from the China Medical Hospital in Taiwan were genotyped. Results: As for Ku70 promoter T-991C, the ORs after adjusted by age and gender of the people carrying TC and CC genotypes were 2.41 (95% CI = 1.53-3.88) and 3.21 (95% CI = 0.96-9.41) respectively, compared to those carrying TT wild-type genotype. The P for trend was significant (P < 0.0001). In the dominant model (TC plus CC versus TT), the association between Ku70 promoter T-991C polymorphism and the risk for gastric cancer was also significant (adjusted OR = 2.48, 95% CI = 1.74-3.92). When stratified by age and gender, the association was restricted to those at the age of 55 or elder of age (TC vs TT: adjusted OR = 2.52, 95% CI = 1.37-4.68, P = 0.0139) and male (TC vs TT: adjusted OR = 2.58, 95% CI = 1.33-4.47, P = 0.0085). As for the other three polymorphisms, there was no difference between both groups in the distributions of their genotype frequencies. Conclusion: In conclusion, the Ku70 promoter T-991C (rs5751129), but not the Ku70 promoter C-57G (rs2267437), promoter A-31G (rs132770) or intron 3 (rs132774), is associated with gastric cancer susceptibility. This polymorphism may be a novel useful marker for gastric carcinogenesis. [ABSTRACT FROM AUTHOR]

A n-/p-SOI MOSFET capped with a standard 380 Å tensile contact etching stop layer (CESL) and a 700 Å compressive CESL and with SOI thicknesses of 500/700/900 Å were measured in this paper. Additionally, external uniaxial compressive stresses with both longitudinal and transverse directions up to 45.7 MPa were applied on the devices sitting on cut silicon bars. Temperature-induced threshold voltage shifts and input-referred voltage noise showed bigger depletion zones and higher noise in the device with compressive CESL. The measurement suggests that both SOI thickness and CESL type are critical for mobility enhancement or degradation of devices. The capped compressive CESL for n-/p-SOI MOSFETs demonstrated higher piezoresistive coefficient compared with tensile CESL under external uniaxial compressive stresses for both longitudinal and transverse configurations. [ABSTRACT FROM AUTHOR]

In next-generation networks, packet classification is used to categorize incoming packets into multiple forwarding classes based on pre-defined filters and make information accessible for quality of service or security handling in the network. To pursue better search performance, numerous algorithms of packet classification have been proposed and optimized for certain filter databases; however, these algorithms may not scale in either storage or speed performance or both for the filter databases with different characteristics. This paper presents an efficient algorithm by combining two complementary algorithms, Cross-producting and Pruned Tuple Space Search, to make packet classification both fast and scalable. Unlike the existing algorithms whose performance is contingent on the filter database attributes, our algorithm shows better scalability and feasibility. We evaluate the performance of our scheme with filter databases of varying sizes and characteristics. The experimental results demonstrate that the new algorithm improves the speed and storage performance simultaneously. We also introduce the procedure of incremental updates. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods yielded a wellcontrolled Type I error rate when tests did not contain any DIF items. M-ST and M-SP began to yield an inflated Type I error rate and a deflated power when tests contained 10% and 20% DIF items, respectively. M-PA maintained an expected Type I error rate and a high power even when tests contained as many as 40% DIF items. An iterative MIMIC procedure was proposed to select a small set of DIF-free items to serve as the anchor in M-PA. It was found in a series of simulations that this procedure yielded a very high rate of accuracy. Two simulated data sets were then analyzed to show applications of these MIMIC methods for DIF assessment in polytomous items. [ABSTRACT FROM AUTHOR]

Electrical stimulation of St. 36 (Zusanli) has been shown to enhance the regularity of gastric myoelectrical activity in healthy subjects. However, the underlying mechanism by which acupuncture alters gastric myoelectrical activity is still not clear. To elucidate the possible role of the autonomic nervous system in mediating the effect of acupuncture, we monitored heart rate variability (HRV), a widely used index of vagal discharge at the sinoatrial node of the heart before, during and after electroacupuncture. In this study, we applied two different frequencies (2 Hz and 100 Hz) of electrical stimulation at St. 36 (Zusanli) and LI. 10 (Shousanli) in 15 healthy volunteers. Low frequency (LF, sympathetic activity), high frequency (HF, vagal activity) and LF/HF ratio (sympathovagal balance) were analyzed and compared at the two different frequencies. The results showed an increase in the LF/HF ratio (indicating greater sympathetic activity) during the post-acupuncture period using 2 Hz of electrical stimulation at St. 36 (Zusanli). However, the overall change was not statistically significant. In addition, the power of LF and HF did not change significantly with electroacupuncture at St. 36 (Zusanli) and LI. 10 (Shousanli). In conclusion, applying 2 Hz or 100 Hz electroacupuncture at St. 36 (Zusanli) or LI. 10 (Shousanli) did not affect cardiovagal activity in normal volunteers. This phenomenon might be due to a difference in presentation in the autonomic nervous system between cardiac and abdominal vagal activity. [ABSTRACT FROM AUTHOR]

In this study, the authors extend the standard item response model with internal restrictions on item difficulty (MIRID) to fit polytomous items using cumulative logits and adjacent-category logits. Moreover, the new model incorporates discrimination parameters and is rooted in a multilevel framework. It is a nonlinear mixed model so that existing parameter estimation procedures and computer packages for non-linear mixed models can be directly adopted to estimate the parameters. Through simulations, it was found that the SAS NLMIXED procedure could recover the parameters fairly well and produce appropriate standard errors, except when the two-parameter adjacent-category logits MIRID was fit to data with a small sample size and a short test length; overall, cumulative logits yielded a better parameter recovery than adjacent-category logits. A real data set about guilt was analyzed with gender as a Level 2 predictor to illustrate applications and applications of the new model. Further model generalization is discussed. [ABSTRACT FROM AUTHOR]

This paper reports on the development and subsequent use of a packet switching communication model for monitoring of power transmission line systems. Modern fault detection and fault location techniques for EHV/UHV transmission networks usually work based on the data measured by a phasor measurement unit (PMU). Digital cameras have also been widely utilized to monitor the physical status of power transmission lines on electricity pylons. PMU measures voltage and current phasors with synchronized time stamps, and then transmits the measured data to a monitoring center for analysis. The transmission of these data is required to be very stable. For the sake of operation speed and system security, the development of an enhanced communication infrastructure that guarantees the quality of service (QoS) for the essential measured data is a crucial issue. We have developed an adaptive routing algorithm for packet switching networks to guarantee the QoS of important power system communications and have conducted computer simulations to demonstrate the effectiveness of the proposed algorithm. The proposed algorithm can minimize transmission delay and reduce the number of redundant transmissions caused by loss of packets. Hence, the simulation results show the feasibility of packet switching networks on monitoring power systems. [ABSTRACT FROM AUTHOR]

This article describes methods to improve the timing performance of solid-state photomultiplier (SSPM) based PET detectors in terms of readout electronics and device level optimization. Coincidence timing measurements based on coupling a 3 × 3 × 10 mm³ LYSO crystal to a Hamamatsu 50 μm 3 mm × 3 mm SSPM were performed. The effect of readout electronics' bandwidth to coincidence timing resolution was measured by applying analog filters with different cutoff frequencies to the SSPM timing circuitry. High pass filtering with a 160 MHz cutoff frequency improved the timing resolution from 269 ± 3.7 ps to 244 ± 3.5 ps. Timing resolution was degraded substantially when cutting off the high frequency components of the SSPM signal, showing a strong dependency of the timing resolution on the high frequency components of the SSPM signal. An SSPM equivalent circuit was described to explain that embedding a quenching capacitor in the quenching network would enhance the high frequency component of the SSPM single photoelectron response, thus improving the timing performance. [ABSTRACT FROM AUTHOR]

In this study, all the advantages of slope parameters, random weights, and latent regression are acknowledged when dealing with component and composite items by adding slope parameters and random weights into the standard item response model with internal restrictions on item difficulty and formulating this new model within a multilevel framework in which Level 2 predictors are added to account for variation in the latent trait. The resulting model is a nonlinear mixed model (NLMM) so that existing parameter estimation procedures and computer packages for NLMMs can be directly adopted to estimate the parameters. Through simulations, it was found that the SAS NLMIXED procedure could recover the parameters in the new model fairly well and produce appropriate standard errors. To illustrate applications of the new model, a real data set pertaining to guilt was analyzed with gender as a Level 2 predictor. Further model generalization is discussed. [ABSTRACT FROM AUTHOR]

The broadcast scheduling problem (BSP) in packet radio networks is a well-known NP-complete combinatorial optimization problem. The broadcast scheduling avoids packet collisions by allowing only one node transmission in each collision domain of a time division multiple access (TDMA) network. It also improves the transmission utilization by assigning one transmission time slot to one or more nodes; thus, each node transmits at least once in each time frame. An optimum transmission schedule could minimize the length of a time frame while minimizing the number of idle nodes. In this paper, we propose a new iterated local search (ILS) algorithm that consists of two special perturbation and local search operators to solve the BSPs. Computational experiments are applied to benchmark data sets and randomly generated problem instances. The experimental results show that our ILS approach is effective in solving the problems with only a few runtimes, even for very large networks with 2,500 nodes. [ABSTRACT FROM AUTHOR]

It is predicted that the number of internet-of-things (IoT) devices will be >28 billion in 2020. Due to the shortage of the conventional radio-frequency spectrum, using visible light communication (VLC) for IoT can be promising. IoT networks may only require very low-data rate communication for transmitting sensing or identity information. The implementation of a VLC link on existing computer communication standards and interfaces is important. Among the standards, universal asynchronous receiver/transmitter (UART) is very popular. We propose and demonstrate a VLC-over-UART system. Bit error rate analysis is performed. Different components and modules used in the proposed VLC-over-UART system are discussed. Then, we also demonstrate a real-time simultaneous temperature, humidity, and illuminance monitoring using the proposed VLC link. [ABSTRACT FROM AUTHOR]

This study implements a scale purification procedure onto the standard MIMIC method for differential item functioning (DIF) detection and assesses its performance through a series of simulations. It is found that the MIMIC method with scale purification (denoted as M-SP) outperforms the standard MIMIC method (denoted as M-ST) in controlling false-positive rates and yielding higher true-positive rates. Only when the DIF pattern is balanced between groups or when there is a small percentage of DIF items in the test does M-ST perform as appropriately as M-SP. Moreover, both methods yield a higher true-positive rate under the two-parameter logistic model than under the three-parameter model. M-SP is preferable to M-ST, because DIF patterns in real tests are unlikely to be perfectly balanced and the percentages of DIF items may not be small. [ABSTRACT FROM AUTHOR]

The Multi-Pixel Photon Counter (MPPC) is a Geiger-mode avalanche photo-diode (APD) developed by Hamamatsu Corp. We propose that it could be a suitable photo-sensor for next-generation time-of-flight PET detectors due to its high photon detection efficiency. We concentrate on the measurement of coincidence timing performance of various MPPCs in conjunction with LYSO crystal scintillators. With 3 mm × 3 mm devices of 50 μm sub-pixels coupled to 3 mm × 3 mm × 10 mm LYSO crystals, we have demonstrated a strong dependence of timing performance on over-voltage and temperature, and analyzed how changes in photon detection efficiency and dark counts would explain the measurements. The best coincidence timing resolution we have achieved between two identical LYSOIMPPC detectors was 240 Ps in FWHM. This was worse than the timing resolution of 220 ps obtained with a Hamamatsu H6533 fast PMT, and contradicted the expected improvement from higher photon detection efficiency. The contradiction could be explained by the slow rise-time of MPPC pulse shape, transit time spread, dark counts and electronic noise from the large capacitance of the MPPC. In particular, the slow rise-time of the MPPC pulse suggests the need for a very low trigger threshold on the timing circuit. Since this makes the detector system more sensitive to noise, this poses additional challenges for ganging multiple devices together into a commercially viable time-of-flight PET block detector. We will discuss this work in detail including other challenge imposed by MPPC characteristics. [ABSTRACT FROM AUTHOR]

Non-homologous end-joining (NHEJ) system is a major route in repairing double strand breaks (DSBs), and is important in maintaining the genome stability. The gene XRCC4 is a central role of the NHEJ system, and it is critical in carcinogenesis. In order to reveal the association between XRCC4 and lung cancer, we recruited 164 lung cancer patients and 649 healthy controls from central Taiwan, investigated seven novel polymorphic variants of XRCC4, includes C-1622T (rs7727691), G-1394T (rs6869366), G-652T (rs2075685), C-571T (rs2075686), intron3 DIP (rs28360071), S247A (rs3734091) and intron7 DIP (rs28360317), and analyzed the association of specific genotype with lung cancer susceptibility. The results showed that the XRCC4 G-1394T is significant in Taiwanese lung cancer and the GT genotype of G-1394T is an obvious risk factor of lung cancer susceptibility (P=0.0049), and the G allele is a risky factor (P=0.0087). As for XRCC4 C-1622T (rs7727691), G-652T (rs2075685), C-571T (rs2075686), intron3 DIP (rs28360071), S247A (rs3734091) and intron7 DIP (rs28360317) polymorphism sites, there was no difference in the distribution between the lung cancer and control groups. The analyzing results of joint effect for smoking habit and XRCC4 G-1394T polymorphism was that people with GT genotype and smoking habit present the highest risk of lung cancer than other groups (OR=2.31, 95% CI=1.43–3.72). The G allele of the XRCC4 G-1394T may be responsible for lung carcinogenesis and maybe useful in early detection and prevention of lung cancer. [ABSTRACT FROM AUTHOR]

Educational and psychological tests are often composed of multiple short subtests, each measuring a distinct latent trait. Unfortunately, short subtests suffer from low measurement precision, which makes the bandwidth-fidelity dilemma inevitable. In this study, the authors demonstrate how a multidimensional Rasch analysis can be employed to take into account the information about the correlation between latent traits such that the precision of each subtest measure can be improved and the correlation between latent traits can be accurately estimated. A real data set of the 13-scale Thinking Styles Inventory was analyzed with the traditional unidimensional approach and the multidimensional approach. The results demonstrate that in contrast to the unidimensional approach, the multidimensional approach yields a much higher level of measurement precision and a more appropriate estimate for the correlation between thinking styles. In conclusion, even short subtests can yield highly precise measures such that the bandwidth-fidelity dilemma is resolved. [ABSTRACT FROM AUTHOR]

Purpose The lengths of CAG repeats in two spinocerebellar ataxia genes, SCA1 and SCA3, were analyzed to determine whether such repeats exist in higher numbers in infertile males. Methods Blood samples were collected from healthy controls, oligozoospermia patients, and azoospermia patients. DNA fragments containing target CAG repeats were amplified by PCR with template DNA purified from the blood samples. CAG repeats in PCR fragments were determined, using ABI PRISM 310 Gene Analyzer. Results In SCA1, the distribution of CAG repeats in oligozoospermic males was different from that of the control group: More alleles had a repeat number that exceeded 32. Conversely, for SCA3, the examined oligozoospermia and azoospermia patients exhibited no differences in distribution of CAG repeats in comparison with the control group. [ABSTRACT FROM AUTHOR]

An effective course in power electronics should ideally contain hands-on design and experimental work as well as theory explanation and simulations. In this paper, a software-reconfigurable e-learning platform for power electronics courses is proposed. The aim of the proposed system is to realize a plat- form capable of constructing a wide range of circuit topologies and control techniques, thus enabling students to gain a better understanding of power electronics converters through practical experiments. The proposed platform consists of a reconfigurable power electronics testbed, a Web-based distance laboratory, and a user interactive e-learning platform. The reconfigurable power electronics testbed can be configured by the students via a Web- based interface to construct a wide variety of converters and inverters. The Internet accessible distance laboratory system permits the instructors and students to remotely conduct experiments over the Internet. The integrated interactive multimedia material can support the educational environment of power electronics courses and can be executed on any modern personal computer (PC) without additional hardware. The advantages of the pro- posed platform include flexibility, friendly user interface, allow for distance waveform measurements, and removal of laboratory time and space constraints. The positive response from students indicates that the proposed platform is extremely useful for power electronics courses. [ABSTRACT FROM AUTHOR]

Raju and Oshima (2005) proposed two prophecy formulas based on item response theory in order to predict the reliability of ability estimates for a test after change in its length. The first prophecy formula is equivalent to the classical Spearman-Brown prophecy formula. The second prophecy formula is misleading because of an underlying false assumption. It can yield negative reliability estimates, especially if the reliability of ability estimates for the old test is low and the new test is shorter. This article identifies the fallacy of the second prophecy formula and demonstrates the scope of its bias in predicting test reliability. [ABSTRACT FROM AUTHOR]

Over the past few decades, ultraviolet (UV) water treatment has become widely recognized and accepted by regulatory agencies as a proven disinfection process. With the increased awareness of health concerns and water quality, UV disinfection is quickly gaining popularity in the consumer market as a safe, effective, and economical approach to disinfection. In order to disinfect properly, conventional UV water-treatment systems keep their light intensity at maximum level regardless of the operating condition; this will result in unnecessary energy waste along with lamp-life-span reduction. In this paper, a new design of high- power-factor low-cost electronic ballast with intelligent control for UV water-treatment system is proposed. For the purposes of energy saving, an intelligent-control algorithm is proposed to dim the luminance of the UV lamp according to the measured water flow rate and UV light intensity. Accurate knowledge of the characteristics of the UV lamps is essential for the ballast design. Therefore, an automatic identification system is also proposed in this paper to obtain the characteristic parameters, which are the dynamic and steady-state profiles of the UV lamps. Systematic design procedures are then presented accordingly. The proposed UV water-treatment system boasts the advantages, such as compactness, low cost, and energy saving, and is suitable for residential users. According to the experimental results, the energy-saving capability of the proposed system is better than 50%. [ABSTRACT FROM AUTHOR]

Purpose - The following research seeks to focus on optimizing the fused deposition modeling (FDM) process of RP systems. Design/methodology/approach - Early stages of this study are based on the Taguchi method in establishing rapid prototyping building factors and their various levels. The ultimate tensile strength, dimension accuracy and surface roughness (SR), are analyzed. Through analysis of variance (ANOVA) and contribution approximation, significant building factors of each quality characteristic and optimal factors level combinations of each best quality characteristic are obtained. The main steps are setting the weight for each quality characteristic of the previous Taguchi method, obtaining the estimated multiple building quality characteristics through integrating the Gray theory, and obtaining a set of optimal building factors. Finally, the result is verified by the Gray theory and the technique for order preference by similarity to ideal solution (TOPSIS) evaluation method. Findings - It is proven that optimal multiple quality characteristic combinations of building factors can be obtained by integrating the Gray theory and the Taguchi method. The result is further verified by the TOPSIS evaluation method, showing that the model can acquire multiple building quality characteristics of rapid prototyping. Research limitations/implications - The method is only applied to FDM in this paper but a similar approach could be applied to other RP systems. Practical implications - RP system use is limited by low product strength, bad SR, and the high dimension errors. This research demonstrates how optimizing the FDM process can improve this situation. Originality/value - The originality of this paper lies in optimizing the rapid prototyping process by integrating the Taguchi method with the Gray relational analysis. [ABSTRACT FROM AUTHOR]

This study explores the effects of ignoring item interaction on item parameter estimation and the efficiency of using the local dependence index Q3 and the SAS NLMIXED procedure to detect item interaction under the three-parameter logistic model and the generalized partial credit model. Through simulations, it was found that ignoring positive item interaction led to overestimation for the discrimination parameters, underestimation for the difficulty parameters, and a Q3 much smaller than zero. As the guessing parameters approached zero, the overestimation for the discrimination parameters became more serious. In contrast, ignoring negative item interaction led to underestimation for the discrimination parameters, overestimation for the difficulty parameters, and a Q3 much larger than zero. As the guessing parameters approached zero, the underestimation for the discrimination parameters became less serious. A modification of posterior predictive p value for Q3 was proposed to detect item interaction and was found to work very well. Direct modeling of item interaction using NLMIXED was demonstrated. [ABSTRACT FROM AUTHOR]

In this study, the authors develop a generalized multilevel facets model, which is not only a multilevel and two-parameter generalization of the facets model, but also a multilevel and facet generalization of the generalized partial credit model. Because the new model is formulated within a framework of nonlinear mixed models, no efforts are needed to develop parameter estimation procedures, and existing computer programs can be directly applied. Through simulations, the authors found that the parameters in the generalized multilevel facets model could be recovered fairly well using the SAS NLMIXED procedure. To illustrate applications of the new model, a real data set about ratings of household appliances was analyzed with gender, age, and education level as the Level 2 predictors. Further model generalization is discussed. [ABSTRACT FROM AUTHOR]