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Measurement of the dwell time and moving speed of a high-activity iridium-192 (Ir-192) source used for high-dose-rate (HDR) brachytherapy is important for estimating the precise dose delivery to a tumor. For this purpose, we used a cerium-doped yttrium aluminum perovskite (YA1OGamma photon imaging was conducted using the gamma camera in list mode for the Ir-192 source of HDR brachytherapy with fixed dwell times and positions. The acquired list-mode images were sorted to millisecond-order interval time sequential images to evaluate the dwell time at each position. Time count rate curves were derived to calculate the dwell time at each source position and moving speed of the source.We could measure the millisecond-order time sequential images for the Ir-192 source. The measured times for the preset dwell times of 2 s and 10 s were 1.98 to 2.00 s full width at half maximum (FWHM) and 10.0 s FWHM, respectively. The dwell times at the first dwell position were larger than those at other positions. We also measured the moving speeds of the source after the dwells while moving back to the afterloader and found the speed increased with the distance from the edge of the field of view to the last dwell position.We conclude that millisecond-order time sequential imaging of the Ir-192 source is possible by using a gamma camera and is useful for evaluating the dwell times and moving speeds of the Ir-192 source.

Purpose We developed a novel and simple method to measure the source positions in applicators directly for high-dose-rate (HDR) brachytherapy based on Cherenkov emission imaging, and evaluated the performance. Methods The light emission from plastic applicators used in cervical cancer treatments, irradiated by an 192 Ir γ-ray source, was captured using a charge-coupled device camera. Moreover, we attached plastics of different shapes, including tapes, tubes, and plates to a metal applicator, to use as screens for the Cherenkov imaging. We determined the source positions and dwell intervals from the light profiles along with the applicator and compared these with preset values and dummy marker measurements. Results The source positions and dwell intervals measured from the light images were comparable to the dummy marker measurements and preset values. The distance from the applicator tip to the first source positions agreed with the dummy marker measurements within 0.2 mm for the plastic tandem. The dwell intervals measured using the Cherenkov method agreed with the preset values within 0.6 mm. The distances measured with three plastic types on the metal applicator also agreed with the dummy marker measurements within 0.2 mm. The dwell intervals measured using the plastic tape agreed with the preset values within 0.7 mm. Conclusions The proposed method should be suitable for rapid and easy quality assurance (QA) investigations in HDR brachytherapy, as it enables source position using a single image. The method allows for real-time, filmless measurements of the source positions to be obtained and is useful for rapid feedback in QA procedures.

To perform complete mesocolic excision with central vessel ligation, it is important to recognize the vessel anomaly and the location of the tumor. For left-sided colon cancer, the variations in the course of the left colic artery and accessary middle colic artery must be recognized preoperatively. Here, we describe our experience with a 57-year-old man who was diagnosed with sigmoid colon cancer with complicated inter-mesenteric connections between the inferior mesenteric artery (IMA) and superior mesenteric artery (SMA), possibly due to median arcuate ligament syndrome. We performed laparoscopic sigmoidectomy with low ligation of the IMA to preserve the extremely enlarged left colic artery. The total operative time was 155 minutes, and the estimated total blood loss was 10 mL. The patient was discharged on postoperative day 9 without any postoperative complications. For patients with vascular anomalies in the left-sided mesocolon, preoperatively ruling out SMA stenosis by using angiography and 3-D CT might be important.

Objective Addiction-like eating (AE) is characterized by food cravings and loss of control over excessive food consumption. This study investigated the associations among emotional factors, personality traits, and AE symptoms in Asian young adults. Method This study included 6,823 Asian university students in South Korea, China, Singapore, Hong Kong/Macao, Japan, and Taiwan. Participants completed the modified Yale Food Addiction Scale (mYFAS) and scales on the Big-Five personality traits, impulsivity, anxiety, and depression. Results 6.2% of the participants met the mYFAS (DSM-IV-TR) food addiction diagnostic threshold. Participants from South Korea (7.9%) had the highest rate of food addiction, while participants from Japan (5.1%) and Taiwan (4.1%) reported the lowest rates. Emotional factors of anxiety and depression were the most robust correlates of AE symptoms, followed by country/region and personality factors of higher impulsivity, higher extraversion, and lower agreeableness. Personality correlates were region-specific. Higher impulsivity was a significant correlate for participants from South Korea and Taiwan, higher extraversion for participants from Singapore and Japan, and lower agreeableness for participants from China and Taiwan. Gender was also a significant correlate for participants from South Korea, Hong Kong/Macao, and Taiwan. Discussion Emotional and personality factors are important correlates of AE symptoms among Asian young adults.

Background Although 18 F-FDG-PET/CT is a widely used diagnostic tool for several malignancies, its efficacy in diagnosing pancreatic neuroendocrine tumors is reported to be controversial because of the short-term follow-up. Methods We retrospectively compared demographics and pathological features between 18 F-FDG-positive and -negative diseases. Additionally, we evaluated whether the avidity of 18 F-FDG-PET/CT affected earlier recurrence after curative treatment of non-functioning tumors. The median duration of observation was 65.6 months. Results Seventy-two patients were enrolled. 18 F-FDG-positive diseases were pathologically advanced and significantly associated with metastatic behavior. In a multivariate analysis, metastatic behavior and WHO tumor grade was independently associated with 18 F-FDG accumulation. Only 25% of functional tumors (4/16) and 8% of insulinomas (1/12) were 18 F-FDG-positive. In a Kaplan-Meier analysis in patients with non-functioning tumors (n = 56), 18 F-FDG-positivity was significantly correlated with poorer recurrence-free survival (RFS) but had no correlation with overall survival. In univariate analysis of factors associated with shorter RFS, male gender, prevalence of nodal metastasis, WHO tumor grade ≥G2, or 18 F-FDG-positive disease were significantly higher in patients with shorter RFS, whereas only 18 F-FDG-positivity was associated with shorter RFS in multivariate analyses. Conclusions The avidity of 18 F-FDG-PET/CT was associated with metastatic behavior of pancreatic neuroendocrine tumors and recurrence after treatment of non-functioning tumors.

The broadening in species' thermal tolerance limits and breadth from tropical to temperate latitudes is proposed to reflect spatial gradients in temperature seasonality, but the importance of seasonal shifts in thermal tolerances within and across locations is much less appreciated. We performed thermal assays to examine the maximum and minimum critical temperatures (CTmax and CTmin , respectively) of a mosquito community across their active seasons. Mosquito CTmin tracked seasonal shifts in temperature, whereas CTmax tracked a countergradient pattern with lowest heat tolerances in summer. Mosquito thermal breadth decreased from spring to summer and then increased from summer to autumn. We show a temporal dichotomy in thermal tolerances with thermal breadths of temperate organisms in summer reflecting those of the tropics ("tropicalization") that is sandwiched between a spring and autumn "temperatization." Therefore, our tolerance patterns at a single temperate latitude recapitulate classical patterns across latitude. These findings highlight the need to understand the temporal and spatial components of thermotolerance variation better, including plasticity and rapid seasonal selection, and the potential for this variation to affect species responses to climate change. With summers becoming longer and increasing winter nighttime temperatures, we expect increasing tropicalization of species thermal tolerances in both space and time.

Computed tomography (CT) data are required to calculate the dose distribution in a patient’s body. Generally, there are two CT number calibration methods for commercial radiotherapy treatment planning system (RTPS), namely CT number‐relative electron density calibration (CT‐RED calibration) and CT number‐mass density calibration (CT‐MD calibration). In a previous study, the tolerance levels of CT‐RED calibration were established for each tissue type. The tolerance levels were established when the relative dose error to local dose reached 2%. However, the tolerance levels of CT‐MD calibration are not established yet. We established the tolerance levels of CT‐MD calibration based on the tolerance levels of CT‐RED calibration. In order to convert mass density (MD) to relative electron density (RED), the conversion factors were determined with adult reference computational phantom data available in the International Commission on Radiological Protection publication 110 (ICRP‐110). In order to validate the practicability of the conversion factor, the relative dose error and the dose linearity were validated with multiple RTPSes and dose calculation algorithms for two groups, namely, CT‐RED calibration and CT‐MD calibration. The tolerance levels of CT‐MD calibration were determined from the tolerance levels of CT‐RED calibration with conversion factors. The converted RED from MD was compared with actual RED calculated from ICRP‐110. The conversion error was within ±0.01 for most standard organs. It was assumed that the conversion error was sufficiently small. The relative dose error difference for two groups was less than 0.3% for each tissue type. Therefore, the tolerance levels for CT‐MD calibration were determined from the tolerance levels of CT‐RED calibration with the conversion factors. The MD tolerance levels for lung, adipose/muscle, and cartilage/spongy‐bone corresponded to ±0.044, ±0.022, and ±0.045 g/cm3, respectively. The tolerance levels were useful in terms of approving the CT‐MD calibration table for clinical use.

To identify novel therapeutic targets for non-small cell lung cancer (NSCLC), we conducted an integrative study in the following 3 stages: (i) identification of potential target gene(s) through shRNA functional screens in 2 independent NSCLC cell lines; (ii) validation of the clinical relevance of identified gene(s) using public databases; and (iii) investigation of therapeutic potential of targeting the identified gene(s) in vitro. A semi-genome-wide shRNA screen was performed in NCI-H358 cells, and was integrated with data from our previous screen in NCI-H460 cells. Among genes identified in shRNA screens, 24 were present in both NCI-H358 and NCI-H460 cells and were considered potential targets. Among the genes, we focused on eIF2β, which is a subunit of heterotrimeric G protein EIF2 and functions as a transcription initiation factor. The eIF2β protein is highly expressed in lung cancer cell lines compared with normal bronchial epithelial cells, and gene copy number analyses revealed that eIF2β is amplified in a subset of NSCLC cell lines. Gene expression analysis using The Cancer Genome Atlas (TCGA) dataset revealed that eIF2β expression is significantly upregulated in lung cancer tissues compared with corresponding normal lung tissues. Furthermore, high eIF2β expression was correlated with poor survival in patients with lung adenocarcinoma, as shown in other cohorts using publicly available online tools. RNAi-mediated depletion of eIF2β suppresses growth of lung cancer cells independently of p53 mutation status, in part through G1 cell cycle arrest. Our data suggest that eIF2β is a therapeutic target for lung cancer.

Building on the literature of the political economy of taxation, this article explores the relationship between political competition and tax revenues using a sample of 89 developing countries from 1988 to 2010. Owing to the inertia of tax variables, we estimate a dynamic panel data model using the Blundell and Bond two†step System†general method of moments. The analysis led to the following results: political competition positively and significantly affects total tax revenues. However, this general pattern slightly differs across the type of taxes; and the net effect of political competition on tax revenues is negative for countries that have adopted fiscal rules. © 2018 UNU†WIDER. Journal of International Development published by John Wiley & Sons, Ltd.

Nonreducible lead-free (Ba,Ca)TiO3 piezoceramics were fabricated by controlling the level of Mn doping. Similar to Mn-doped (Ba0.85Ca0.15)TiO3 ceramics sintered in air, stable dielectric properties with temperature change were achieved for the nonreducible sample by stabilizing the tetragonal phase of BaTiO3 over a wide temperature range. In addition, optimization of the level of Mn doping was very effective in improving the sintered density and electrical resistivity for (Ba0.85Ca0.15)TiO3 ceramics sintered under a low oxygen partial pressure. The valence state of doped Mn in nonreducible (Ba,Ca)TiO3 after sintering was confirmed to be Mn2+ or Mn3+ by electron spin resonance analysis. Sintered bodies of 1 mol% Ba excess and 1 mol% Mn-doped (Ba0.85Ca0.15)TiO3, which were sintered at 1350°C in a H2(0.3%)/Ar atmosphere, exhibited sufficient sintered density and resistivity to allow the characterization of several electrical properties. The ferroelectric, field-induced strain, and piezoelectric properties of the nonreducible (Ba0.85Ca0.15)TiO3 ceramics sintered in the reducing atmosphere were comparable with those of (Ba0.85Ca0.15)TiO3 samples sintered in air.

Tetraethylenepentamine (TEPA) components are separated by fractional distillation, and the structure of each fraction is established using spectroscopic methods. Then, solid sorbents incorporating these components are prepared, and the capacities and rates of CO2 absorption of the sorbents are evaluated to elucidate how the molecular structure affects the absorption performance.

Exploiting exogenous and endogenous stimulus-responsive degradable nanoparticles as drug carriers can improve drug delivery systems (DDSs). The use of hollow nanoparticles may facilitate degradation, and combination of DDS with photodynamic therapy (PDT) and photothermal therapy (PTT) may enhance the anticancer effects of treatments. Here, a one-pot synthetic method is presented for an anticancer drug (doxorubicin [DOX]) and photosensitizer-containing hollow hybrid nanoparticles (HNPs) with a disulfide and siloxane framework formed in response to exogenous (light) and endogenous (intracellular glutathione [GSH]) stimuli. The hollow HNPs emit fluorescence within the near-infrared window and allow for the detection of tumors in vivo by fluorescence imaging. Furthermore, the disulfides within the HNP framework are cleaved by intracellular GSH, deforming the HNPs. Light irradiation facilitates penetration of GSH into the HNP framework and leads to the collapse of the HNPs. As a result, DOX is released from the hollow HNPs. Additionally, the hollow HNPs generate singlet oxygen (1O2) and heat in response to light; thus, fluorescence imaging of tumors combined with trimodal therapy consisting of DDS, PDT, and PTT is feasible, resulting in superior therapeutic efficacy. Thus, this method may have several applications in imaging and therapeutics in the future.

Objectives The objectives of this study were to establish a magnetic resonance imaging-based classification system for canine hyperadrenocorticism according to pituitary gland extension, determine indications for trans-sphenoidal hypophysectomy, and clarify the prognosis for each disease grade. Methods A 5-point classification system (Grades 1 to 5) was developed based on tumour extension in dorsal and cranio–caudal directions. Cases were then classified as Type A: no arterial circle of Willis or cavernous sinus involvement and Type B: cases in which these blood vessels were involved. Results Medical records and magnetic resonance imaging data of 37 cases with hyperadrenocorticism were reviewed. Thirty-three cases underwent surgery; 4 Grade 5 cases did not have appropriate indications for surgery, and other therapies were used. Complete resection was achieved for 3, 3, 22 and 1 Grade 1A, 2A, 3A and 3B cases, respectively. Resection was incomplete in 1, 1 and 2 Grade 3A, 3B and 4B cases, respectively. Remission was achieved in 29 cases. Recurrence occurred in 4 cases, all of which were classified as Grade 3. Clinical Significance Dogs with Type A, Grade 1 to 3 hyperadrenocorticism had a good prognosis following trans-sphenoidal hypophysectomy. Grade 3B, 4 and 5 cases may not be suitable for this surgery.

Tracheo‐innominate artery fistula (TIF) is a rare but life‐threatening complication of tracheostomy. We describe a 44‐year‐old man who was admitted for a pressure ulcer infection with a third tracheostomy in place. He showed massive hemoptysis from the TIF, followed by cardiopulmonary arrest. The cuff of the tube was hyperinflated; however, even a slight movement of the tube resulted in recurrent massive hemorrhage. Thus, an endovascular stent graft was placed. Our case shows that sentinel bleeding may be found prior to TIF, and an endovascular repair can be a lifesaving temporizing option, when the hemorrhage was not controlled by hyperinflating the cuff of the tube.

This paper aims at assessing the relationship between infrastructure development and competitiveness in North Africa. Based on the World Bank data, we analyze the infrastructure indicators of four North African countries over the period 1996–2012 and estimate the elasticity of competitiveness with respect to infrastructure development. We ?rst argue that competitiveness could be improved by investing more on infrastructure. Although comparison with sub-Saharan Africa reveals that important progress has been made in North Africa in terms of quantity, countries need to improve the infrastructure quality by investing in green energy, in maintenance, in public private partnerships and in regional infrastructure. Econometric analysis con?rms that a 1 percent increase in infrastructure quality raises competitiveness by 0.64 percent. Country speci?c elasticity is respectively 0.22 in Algeria, 1.42 in Egypt, 0.36 in Tunisia and 0.56 in Morocco. Based on these results, appropriate policy recommendations are discussed.

La presente etude fournit l’evidence de l’ef?cacite de l’aide en faisant usage d’un echantillon de 34 pays d’Afrique sub-saharienne sur la periode 1990–2010. Apres prise en compte de l’endogeneite de l’aide, les resultats de l’estimation revelent que l’aide a un effet positif sur la croissance uniquement lorsque l’estimation est controlee du niveau de la gouvernance. La dynamique comparative quant 'a elle montre que la gouvernance et l’education sont les principaux canaux de transmission de l’aide 'a la croissance en environnement stable. En revanche, en environnement de post con?it, l’aide affecte la croissance via l’investissement en capital public (infrastructure). En?n, l’approche de decomposition d’Oaxaca-Blinder montre que l’ecart en termes de montants d’aide recus n’explique pas les differences de croissance observees entre pays stables et pays en situation de post con?it. Sur la base de ces resultats, les implications de politiques economiques sont discutees en conclusion.