Synthesis and luminescence of Sr2CeO4 fine particles

Fine particles of a blue emission phosphor Sr₂CeO₄ have been synthesized using a chemical co-precipitation technique, and the textual and luminescent properties were compared with the one synthesized by the conventional solid-state reaction method. Particle size and distribution of the Sr₂CeO₄ fine powder prepared by the co-precipitation process were smaller and narrower than those obtained by the samples prepared from the conventional one. The emission intensity of the fine particles was equal to that of the larger particles prepared from the solid-state reaction, on the contrary to the general tendency that emission intensity decrease with particle size reduction. Although no Ce³⁺ peaks were observed in EPR measurements, X-ray photoelectron spectra of the samples clearly elucidated the existence of Ce³⁺ only on the surface of Sr₂CeO₄.     

Post-lunch nap as a worksite intervention to promote alertness on the job.

A worksite study was conducted to examine whether a 15-min nap during a post-lunch rest period would affect subsequent alertness, performance, and nocturnal sleep in eight factory workers under a 3-week protocol. Subjects were asked to take the nap at 12:30 h on a reclining chair during the nap week, and to remain awake during the no-nap week. The order of these 2 weeks was counterbalanced between the subjects. During the third, follow-up week, each subject determined whether or not she/he would nap. Alertness on the job and nocturnal sleep were assessed using a sleep diary. Wrist activity was also recorded during sleep at night. Choice reaction time task (RT) was performed at 10:00 and 15:00 h every day of the nap week and every other day of the no-nap and follow-up weeks. Perceived alertness was significantly higher in the afternoon after nap than after no nap at the end of the week. Similar effects were observed during the follow-up week where almost half of the subjects napped. No significant differences between the three weeks were found for RT performance or nocturnal sleep. Workers' attitudes toward the nap were favourable. Although further intervention research is required, our results suggest that post-lunch napping may have the potential to promote daytime alertness at work.     

Chronic myelomonocytic leukemia with repeated respiratory failure associated with leukocytosis following splenic arterial embolization and splenectomy

A 32-year-old female was admitted due to splenomegaly and leukocytosis in September, 1993. The leukocyte count was 26,900/microliter with 29% monocytes (7,800/microliter). A diagnosis of the chronic phase of chronic myelomonocytic leukemia was made. On November 19, 1993, splenic arterial embolization was performed. After the embolization, the leukocyte count rapidly increased, and acute respiratory failure developed. The respiratory condition was improved by methylprednisolone (m-PRED) pulse therapy. Subsequently, the effectiveness of chemotherapy gradually decreased, and there was an increase in the leukocyte count. Respiratory failure developed again but was successfully treated with m-PRED pulse therapy in addition to aclarubicin. On July 4, 1995, splenectomy was performed. The leukocyte count rapidly increased, and acute respiratory failure again developed. She did not respond to m-PRED pulse therapy, but the respiratory condition was markedly improved by leukoplasmapheresis. The respiratory failure in this patient may be associated with capillary leak syndrome due to neutrophilia. In addition, stasis of increased monocytes in the pulmonary capillaries and their infiltration into the pulmonary parenchyma and alveoli was thought to have occurred.     

Local Epidermal Endocrine Estrogen Protects Human Melanocytes against Oxidative Stress,a Novel Insight into Vitiligo Pathology

As the outermost barrier of the body, skin is a major target of oxidative stress. In the brain, estrogen has been reported synthesized locally and protects neurons from oxidative stress. Here, we explored whether estrogen is also locally synthesized in the skin to protect from oxidative stress and whether aberrant local estrogen synthesis is involved in skin disorders. Enzymes and estrogen receptor expression in skin cells were examined first by quantitative real-time PCR and Western blot analyses. Interestingly, the estrogen synthesis enzyme was mainly localized in epidermal keratinocytes and estrogen receptors were mainly expressed in melanocytes among 13 kinds of cultured human skin cells. The most abundant estrogen synthesis enzyme expressed in the epidermis was 17β-hydroxysteroid dehydrogenase 1 (HSD17β1) localized in keratinocytes, and the most dominant estrogen receptor expressed in the epidermis was G protein-coupled estrogen receptor 1 (GPER1) in melanocytes. To investigate whether keratinocyte-derived estradiol could protect melanocytes from oxidative stress, cultured human primary epidermal melanocytes (HEMn-MPs) were treated with H₂O₂ in the presence or absence of 17β estradiol or co-cultured with HSD17β1 siRNA-transfected keratinocytes. Keratinocyte-derived estradiol exhibited protective effects against H₂O₂-induced cell death. Further, reduced expression of HSD17β1 in the epidermis of skin from vitiligo patients was observed compared to the skin from healthy donors or in the normal portions of the skin in vitiligo patients. Our results suggest a possible new target for interventions that may be used in combination with current therapies for patients with vitiligo.     

Microstructure of TiO2 and ZnO Films Fabricated by the Sol-Gel Method

Titanium dioxide and zinc oxide films were fabricated by spin-on and dip-coating methods. Both types of films exhibited columnar grains when the single coating was thin, ∼10 nm. The columnar TiO₂ films were dense, as confirmed by their density values calculated from the refractive index and TEM results. The addition of Al cations into the ZnO suppressed grain growth, because Zn had a lower diffusivity in the doped films. The doped ZnO films had nearly the same electrical resistivity as that of the undoped films.     

Reconstructing the World’s Museums

Virtual exploration tools for large indoor environments (e.g. museums) have so far been limited to either blueprint-style 2D maps that lack photo-realistic views of scenes, or ground-level image-to-image transitions, which are immersive but ill-suited for navigation. On the other hand, photorealistic aerial maps would be a useful navigational guide for large indoor environments, but it is impossible to directly acquire photographs covering a large indoor environment from aerial viewpoints. This paper presents a 3D reconstruction and visualization system for automatically producing clean and well-regularized texture-mapped 3D models for large indoor scenes, from ground-level photographs and 3D laser points. The key component is a new algorithm called “inverse constructive solid geometry (CSG)” for reconstructing a scene with a CSG representation consisting of volumetric primitives, which imposes powerful regularization constraints. We also propose several novel techniques to adjust the 3D model to make it suitable for rendering the 3D maps from aerial viewpoints. The visualization system enables users to easily browse a large-scale indoor environment from a bird’s-eye view, locate specific room interiors, fly into a place of interest, view immersive ground-level panorama views, and zoom out again, all with seamless 3D transitions. We demonstrate our system on various museums, including the Metropolitan Museum of Art in New York City—one of the largest art galleries in the world.     

Studying re-opened bugs in open source software

Bug fixing accounts for a large amount of the software maintenance resources. Generally, bugs are reported, fixed, verified and closed. However, in some cases bugs have to be re-opened. Re-opened bugs increase maintenance costs, degrade the overall user-perceived quality of the software and lead to unnecessary rework by busy practitioners. In this paper, we study and predict re-opened bugs through a case study on three large open source projects—namely Eclipse, Apache and OpenOffice. We structure our study along four dimensions: (1) the work habits dimension (e.g., the weekday on which the bug was initially closed), (2) the bug report dimension (e.g., the component in which the bug was found) (3) the bug fix dimension (e.g., the amount of time it took to perform the initial fix) and (4) the team dimension (e.g., the experience of the bug fixer). We build decision trees using the aforementioned factors that aim to predict re-opened bugs. We perform top node analysis to determine which factors are the most important indicators of whether or not a bug will be re-opened. Our study shows that the comment text and last status of the bug when it is initially closed are the most important factors related to whether or not a bug will be re-opened. Using a combination of these dimensions, we can build explainable prediction models that can achieve a precision between 52.1–78.6 % and a recall in the range of 70.5–94.1 % when predicting whether a bug will be re-opened. We find that the factors that best indicate which bugs might be re-opened vary based on the project. The comment text is the most important factor for the Eclipse and OpenOffice projects, while the last status is the most important one for Apache. These factors should be closely examined in order to reduce maintenance cost due to re-opened bugs.     

A control method with pheromone information for a transport system

Since the control methods of a transport system between processing machines are specialized for each layout of the system, it is difficult to design prompt schedules and control logic for new complicated systems, especially in cases of machine faults or restructuring the system to modify the layout. In this article, we describe a multiagent transport control system which utilizes pheromone information. Each element of the system acts as an agent and estimates the appropriate path and time to drive out the products using information obtained by communication with other elements as well as pheromone information deposited on the tracks of the products.