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The micromix (MMX) combustion concept is a DLN gas turbine combustion technology designed for high hydrogen content fuels. Multiple non-premixed miniaturized flames based on jet in cross-flow (JICF) are inherently safe against flashback and ensure a stable operation in various operative conditions. The objective of this paper is to investigate the influence of pressure on the micromix flame with focus on the flame initiation point and the NOx emissions. A numerical model based on a steady RANS approach and the Complex Chemistry model with relevant reactions of the GRI 3.0 mechanism is used to predict the reactive flow and NOx emissions at various pressure conditions. Regarding the turbulence-chemical interaction, the Laminar Flame Concept (LFC) and the Eddy Dissipation Concept (EDC) are compared. The numerical results are validated against experimental results that have been acquired at a high pressure test facility for industrial can-type gas turbine combustors with regard to flame initiation and NOx emissions. The numerical approach is adequate to predict the flame initiation point and NOx emission trends. Interestingly, the flame shifts its initiation point during the pressure increase in upstream direction, whereby the flame attachment shifts from anchoring behind a downstream located bluff body towards anchoring directly at the hydrogen jet. The LFC predicts this change and the NOx emissions more accurately than the EDC. The resulting NOx correlation regarding the pressure is similar to a non-premixed type combustion configuration.

Japan has reported 26 cases of coronavirus disease 2019 (COVID-19) linked to cruise tours on the River Nile in Egypt between March 5 and 15, 2020. Here, we characterized the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome of isolates from 10 travelers who returned from Egypt and from patients possibly associated with these travelers. We performed haplotype network analysis of SARS-CoV-2 isolates using genome-wide single-nucleotide variations. Our analysis identified two potential Egypt-related clusters from these imported cases, and these clusters were related to globally detected viruses in different countries.

Background The epidemiology of Kawasaki disease (KD) shows seasonal variations, although the etiology of KD is unknown. In this study, we compared the clinical epidemiology of KD onset in winter versus that in summer to identify its etiology, that is, infectious agents. Methods Epidemiologic features of KD were compared between two seasons with high incidence (January [winter] and July [summer]) using a dataset of the 22nd nationwide survey in Japan. Data on patients who visited hospital during 2011–2012 in Japan were analyzed after adjusting for age differences. Subgroup analysis was carried out for day of illness at the day of first hospital visit. Results The total number of KD patients reported in the survey was 26 691. The number of patients who visited hospital with KD for the first time in January and July was 2,812 and 2,302, respectively. The proportion of patients in the age group 15 months–3 years was 38.8% in January and 33.5% in July. Mean serum albumin was significantly lower in January than in July (at days 2–5 of illness, P

Sporadic cases of legionellosis have increased in Saitama Prefecture. This study aimed to understand the characteristics and incidence of legionellosis in Saitama Prefecture by studying the corresponding data from Tokyo and all over Japan. We analyzed cases of legionellosis registered from 2005 through 2009 in the annual reports of the Infectious Disease Surveillance Center. There were two peaks in the incidence of legionellosis in Japan between June and November, and a trough between February and May every year. Similar seasonal characteristics were observed in both Tokyo and Saitama. Proper management of risk factors-such as cooling towers and other aerosol-generating devices, before and during the seasonal increase in these incidences-is essential as a prophylactic measure against legionellosis.

Background: Kawasaki disease (KD) has been diagnosed in more than 60 countries. Seasonal trend of the patients with KD is observed in many countries. Little is known about the difference between the patient groups in the term of high incidence. Objective: The aim of this study was to characterize the two patient groups during the winter and summer seasons in Japan. Methods: Epidemiologic characteristics were compared between January and July, through the 22th nationwide survey included patients who visited hospitals during 2011-2012. The proportions of survey items were observed by age-adjustment. Results: The total number of patients during 2011-12 was 26,691, the number of patients was 2812 in January and 2302 in July, and the male/female ratio was 1.4, respectively. The patients Discussion: The difference in age distribution in the two patient groups diagnosed in January and July was observed. The symptom had a slight difference, too. These result do not contradict a hypothesis that onset of KD is concerned with plural infections with different seasonal trend and targeting for the specific age. The association between low levels of serum albumin and cardiac sequelae has been known. The association between this class and the patients in the specific season will be clear in future epidemiologic study. Conclusion: This study clarified part of the characteristic of the patient diagnosed in the different seasons.

Background: From January through September 2001, seven patients were admitted to Fukaya Red Cross Hospital with typical clinical manifestations of acute hepatitis. Six were outpatients of the clinic, which is located near the hospital. An extensive survey of clinic outpatients conducted by the local health department revealed six more new acute hepatitis cases during this period. Methods: A case control study was carried out to identify potential risk factors for infection. In total, 1946 outpatients with clinic records were scheduled to undergo hepatitis C virus (HCV)-antibody testing. For the HCV-Ab positive patients, HCV-RNA was subtyped and quantified, and sequences of HCV hypervariable region 1 were determined. Results: Ultimately, 12 patients with acute hepatitis and two asymptomatic subjects were found to be a part of this outbreak. HCV isolates were divided into three major groups using phylogenetic tree analysis. Only a past history of visiting the clinic was significantly associated with acute hepatitis. The timing of the parenteral medical procedure at the clinic and the onset of acute hepatitis strongly suggested association of the two events. Conclusions: Our findings suggest that nosocomial HCV infection can occur in an outpatient clinic, even in countries where post-transfusion hepatitis has been almost entirely eliminated.

The objective of this study was to assess the need for and usefulness of training programs for Local Infectious Disease Surveillance Center (LIDSC) staff.A structured questionnaire survey was conducted to assess the needs and usefulness of training programs. The subjects of the survey were participants of a workshop held after an annual conference for the LIDSC staff. Data on demographic information, the necessity of training programs for LIDSC staff, the themes and contents of the training program, self-assessment of knowledge on epidemiology and statistics were covered by the questionnaire.A total of 55 local government officials responded to the questionnaire (response rate: 100%). Among these, 95% of participants believed that the training program for the LIDSC staff was necessary. Basic statistical analysis (85%), descriptive epidemiology (65%), outline of epidemiology (60%), interpretation of surveillance data (65%), background and objectives of national infectious disease surveillance in Japan (60%), methods of field epidemiology (60%), and methods of analysis data (51%) were selected by over half of the respondents as suitable themes for training programs. A total of 34 LIDSC staff answered the self-assessment question on knowledge of epidemiology. A majority of respondents selected "a little" or "none" for all questions about knowledge. Only a few respondents had received education in epidemiology.The results of this study indicate that LIDSC staff have basic demands for fundamental and specialized education to improve their work. Considering the current situation regarding the capacity of LIDSC staff, these training programs should be started immediately.

Sporadic cases of legionellosis have increased in Saitama Prefecture. This study aimed to understand the characteristics and incidence of legionellosis in Saitama Prefecture by studying the corresponding data from Tokyo and all over Japan. We analyzed cases of legionellosis registered from 2005 through 2009 in the annual reports of the Infectious Disease Surveillance Center. There were two peaks in the incidence of legionellosis in Japan between June and November, and a trough between February and May every year. Similar seasonal characteristics were observed in both Tokyo and Saitama. Proper management of risk factors-such as cooling towers and other aerosol-generating devices, before and during the seasonal increase in these incidences-is essential as a prophylactic measure against legionellosis.

Maternal guinea pigs were injected with mercuric chloride (HgCl2; 1 mg Hg/kg body weight) or methylmercury (MeHg; 1 mg Hg/kg) 12 h after parturition, and exposure of the offspring to mercury (Hg) via breast milk were studied on days 3, 5 and 10 postpartum. Milk Hg concentrations were lower than maternal plasma Hg concentrations regardless of the form of Hg given to the dams. Milk Hg was higher in HgCl2-treated dams than in MeHg-treated dams. In MeHg-treated dams, MeHg was separately determined. While the ratio of MeHg to T-Hg decreased in the dams' plasma, it did not in the milk. There was a strong correlation between milk and plasma T-Hg concentrations in HgCl2 treated dams. In the milk of MeHg-treated dams, the plasma MeHg concentrations correlated better than did the plasma T-Hg concentrations. In the offspring, regardless of the chemical forms of Hg given to the dams, the highest Hg concentrations were found in the kidney, followed by the liver and the brain. Brain Hg concentrations were, however, significantly higher in the offspring of MeHg-treated dams than in those of HgCl2-treated dams. In addition, Hg levels in the major organs of the offspring of HgCl2-treated dams peaked on day 5 postpartum, while those of MeHg-treated dams did not show a significant decrease up to day 10 postpartum. These facts indicate that the two chemical forms of Hg were transferred to the offspring via the breast milk and were distributed differently, depending on the chemical form, to the offspring's tissues.

Blood and urine samples from cloisonne ware workers were assayed for Pb, Cr, Cd, Mn, Sb, Co and Cu for biological monitoring. Mean blood Pb levels were 47.8 +/- 27.3 micrograms/dl (111-13.3 micrograms/dl) for 49 cloisonne glaze workers, and 0.97 +/- 0.47 microgram/dl (2.4-0.6 microgram/dl) for 62 normal subjects. There was a distinct difference between the 2 groups, and slight differences (p0.01) in mean Cr, Cd and Mn levels. There was a distinct difference in mean urinary Pb level between the 2 groups, and slight differences (p0.01) in mean Cr, Cd and Mn levels. The correlation coefficient, r, between blood Pb and Cd levels was 0.631 (p0.01) for 132 subjects consisting of cloisonne ware workers and normal subjects. r between blood Pb and blood Cr levels was 0.501 (p0.01), and that between blood and urinary Pb levels, 0.794 (p0.01). The above assays showed that glaze workers at cloisonne plants suffer severe exposure to lead and slight exposure to Cd and Cr.

The influence of essential metals, like zinc, selenium, and calcium, on the nephrotoxicity of cadmium was studied in primary cultures of rat proximal tubular cells. Damage to kidney cells was assessed by measuring the release of lactate dehydrogenase (LDH), γ-glutamyltranspeptidase (GTP), and β-N-acetylglucosaminidase (NAG) from cells into the medium and the cellular concentration of protein. Incubation with 200 μM cadmium in the presence of equivalent molar or lower concentrations of zinc and selenium showed greater release of LDH and NAG than cadmium alone, indicating an enhanced effect. However, metallothionein (MT) induced by pretreatment with a nontoxic concentration of zinc decreased significantly the release of enzyme from cells and elevated cellular protein levels in response to MT levels. MT provided partial protection against the nephrotoxicity of cadmium. Decreased calcium levels in the incubation medium also resulted in markedly increased release of LDH and NAG from cells exposed to cadmium and reduced cellular protein levels. These findings suggest that variations in zinc and calcium intake may affect the development of cadmium-induced renal dysfunction.

Exposure to an exogenous chemical via milk causes superimposition on the body burden that might have already existed in the neonatal organism due to in utero exposure. Such exposure via breast milk is avoidable, although transplacental exposure cannot be avoided at present. In this paper, mercury exposure via breast milk was examined in an animal model. Maternal guinea pigs were shortly exposed to mercury vapor at the mean concentrations of 6-10 mg/m3 immediately after parturition. Newborn guinea pigs were then nursed by the natural mothers. Mercury concentrations in breast milk and tissue samples were determined on d 3, 5, and 10 postpartum. Mercury concentrations in breast milk were slightly lower than plasma mercury concentrations of the maternal guinea pigs over the observation period. However, the decrease in the mercury concentration in breast milk with time was slower than that in maternal plasma. Mercury concentrations in major organs of the neonates were highest in kidney, followed by liver and lung. In brain and whole blood, mercury concentrations were slightly elevated compared with the nonexposed control. Organ distribution of mercury in the suckling neonates indicated that they were exposed via breast milk to inorganic, not elemental, mercury.

Obesity in children seems to be a risk factor for chronic diseases in adulthood. From the viewpoint of preventive medicine, factors influencing the development of obese children should be removed early in life. The purpose of this study was to the elucidate relationship between obesity in 3-year-old children and both behavioral and environmental factors by conducting a case-control study. Subjects were selected from the Toyama study. Matched-pair comparisons were performed between obese children whose Kaup’s index was 18 or more (N=117) and control children (N=234) . Multivariate stepwised logistic regression analysis also applied to assess influence of confounding factors. The results indicated that the following 6 factors significantly influenced the development of obese 3-year-old children in exact Fisher’s method analysis (p

We investigated the background levels of total mercury in blood and urine samples from Japanese subjects without occupational exposure to mercury vapor. Blood and urine specimens were decomposed in sealed Teflon containers, and total mercury concentration was measured by reductive vaporization-gold amalgam capture-atomic absorption spectrophotometry. The mean total mercury concentration in the blood of 56 women aged 34-65 was 18.2 +/- 9.9 ng/ml (range 3.9-56.8 ng/ml). The mean total mercury concentration in the urine of 130 men aged 22-39 was 2.33 +/- 1.50 micrograms/l (range 0.27-10.26 micrograms/l). The mean total mercury concentration in urine adjusted by specific gravity was 2.19 +/- 1.15 micrograms/l (range 0.68-7.68 micrograms/l), and that adjusted by creatinine was 1.51 +/- 0.68 micrograms/g creatinine (range 0.39-4.21 micrograms/g creatinine). These concentrations did not differ greatly from those reported from Europe and Japan. In expressing the total mercury concentration in urine, the creatinine-adjusted range between the minimum and maximum values was smaller than the range adjusted by specific gravity.

(1)サーブレシーブに関して,主流である5人シフトでの成績と,スピード・コンビネーション攻撃を最重視した2人or3人シフトでの成績を比較検討した。(2)サーブレシーブに関しては,2人or3人シフトをとる島根クラブの方がA・B評価値が高く,このシフトでも,スピード・コンビネーションでの展開を狙っていくことが充分可能であるといえる。(3)バレーボールの試合は,対戦チームとの相対関係にあり,その要素は攻防において多種ある。この相対関係にあるということが,体力・技術のより高度化を生み出してきている。しかし,サーブ・サーブレシーブは,比較的画一的な関係にあるのでなおざりにされてきていたように思う。これからのサーブレシーブ・フォーメーションの方法として,経験的に1つの方法だけしかとらないということではなく,各チーム内のメンバー構成や技量及び攻撃パターン等をよくかんがみて,5人型から2人型までを随時取り入れ,より合理的に,又より確実にレシーブできるフォーメーションに積極的に取り組んでいく必要がある。本研究の要旨は,第35回日本体育学会(1984,鹿児島)において発表したものである。