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High-density single nucleotide polymorphisms (SNPs) can detect distant relatives even in the context of pairwise kinship analysis. Although DNA microarrays conveniently generate genome-wide SNP data, they require large quantities of high-quality DNA. Genotyping data obtained from low-quantity and low-quality samples are likely unreliable owing to the incidence of no-called or mistyped SNPs. In this study, we examined the effects of insufficient sample densities and sample degradation on the efficacy of kinship analysis. While low DNA amounts had a minor effect, DNA degradation led to a significant increase in no-call rates and error rates. Posterior probabilities of kinship determination, calculated using the index of chromosomal sharing, were markedly lower in proportion to the no-call rates and error rates. We also investigated the effect of genotype imputation to complement the no-called genome data utilizing SNPs reference panels. We found that the posterior probability of the relative-assumed person increased with genotype complementation in case of mild degradation, even with mistyped genotypes. Therefore, DNA microarray with imputation is a promising method for analyzing forensic DNA samples taken from situations where DNA quantity and quality may be compromised, such as disaster victim identification using pairwise kinship analysis.

This study aimed to develop the Grief State Scale for Nurses to measure the level of nurses' grief and to identify items influencing grief levels among Indonesian nurses. A total of 267 questionnaires were analyzed and interpreted. Statistical analyses were performed using descriptive statistics and exploratory factor analysis. Items influential in increasing nurses' grief were relating death with personal loss; patient's age/illness similar to nurse's family members; and having rapport with patients. Time and place to express grief, allocation of grieving time, and sharing collegial emotional expressions were items found to decrease levels of nurses' grief.

The symptoms of attention deficit hyperactivity disorder (ADHD) are inattention, hyperactivity, and impulsiveness. Physicians often prescribe methylphenidate (MPH) for children with ADHD for long periods of time. The purpose of the present study was to investigate the usefulness of near-infrared spectroscopy (NIRS) for evaluating drug effects and improvements in medication adherence in children with ADHD. Subjects were 10 male children diagnosed with ADHD : average age, 9.3 years, and 10 boys with typical development : average age 9.5 years. Children with intellectual disability, autism, and obvious depressive symptoms were excluded. The present study revealed that in the ADHD group, oxy-Hb concentrations in the left and right lateral prefrontal cortex significantly increased during the execution of the Stroop color-word test in both channels when taking MPH. This method was considered to be useful for assessing drug effects on ADHD because NIRS is an objective indicator for evaluating ADHD executive dysfunction and visualizes the activation of frontal lobe function by MPH. A pediatric neurologist explained the results of NIRS while presenting images to the ADHD group, and medication adherence and the drug-taking ratio both markedly improved. Therefore, this therapeutic explanation is an effective strategy for improving medication compliance and adherence among patients. J. Med. Invest. 68 : 53--58, February, 2021.

Dieulafoy lesions are rare vascular malformations of the gastrointestinal tract; however, they can lead to fatal vascular bleeding. Immunoglobulin G4-related disease (IgG4-RD) is a rare systemic fibroinflammatory disease involving multiple organs, including the vasculature. To date, no autopsy reports of Dieulafoy lesions with IgG4-RD have been described in the literature. A 48-year-old man was found dead in his home with hematochezia. Postmortem computed tomography revealed high-density gastric contents and an enlarged iso-density area in the pancreas, indicating gastric hemorrhage and mass-forming lesions. Macroscopic and histological examinations revealed an ulcer of the body of the stomach with a large amount of hemorrhage from the enlarged artery in the submucosal layer, confirming the rupture of the Dieulafoy lesion. Moreover, lymphocyte infiltrations with increased IgG4 positive cells were found in the pancreas, thyroid gland, and arteries in non-ulcer regions of the stomach, suggesting IgG4-RD. Serum biochemical analysis showed elevated levels of inflammatory mediators, such as IgE, soluble-interleukin-2 receptor, and C-reactive protein. These findings suggest that systemic inflammation caused by IgG4-RD could, at least in part, contribute to the development of Dieulafoy lesions and fatal rupture of the lesion. This case report highlights the importance of autopsy research focusing on Dieulafoy lesions and IgG4-RD to promote awareness and a better understanding of the relationships between these treatable diseases to establish earlier and effective interventional strategies for better patient outcomes.

Aim This study aimed to describe the interactions between healthcare robots and older persons in two selected institutions. Methods A qualitative descriptive analysis study using simultaneous observations of healthcare robot and older person interactions was conducted at two healthcare institutions in Japan. The Pepper robot equipped with Care Prevention Gymnastics Exercise programs was used in two situations: (a) exercise regimen led by Pepper; and (b) interactive dialogue between Pepper and older persons during the exercise process. These interactions were recorded using audiovisual equipment and analyzed using content analysis thereby revealing four thematic categories. Interpretation and discussion were structured based on assumptions of the Transactive Relationship Theory of Nursing. Results The analysis revealed four thematic categories: (a) intermediary participation of healthcare practitioners; (b) technologies of care for practice; (c) human-robot interactions involving artificial intelligence; and (d) valuing safety in nursing through technology. Conclusion Interactions between healthcare robots and older persons may improve quality of care. However, issues regarding fidelity and functionality of dialogic conversations, and ensuring safety and security of using healthcare robots are recognized as critical nursing practice concerns in healthcare robot use in institutional settings.

Background: The effects of the COVID-19 pandemic are not limited to physical aspects among infected people, but also include psychological aspects among uninfected people, such as community people and health care workers. The study aimed to describe the current mental health conditions prevalent among communities and health care workers during the COVID-19 pandemic. Method: An integrative review was conducted following the steps and framework of Whittemore and Knafl. Relevant articles were obtained from electronic databases, such as Science Direct, Scopus, PubMed, and Google Scholar using the keywords: “mental health”, “Stress”, “Depression”, “COVID-19”, “SARS-CoV-2”, “health care workers”, and “community people”. Eighteen articles were selected that met the inclusion criteria: full text, written in English, published in 2020, original research and review articles discussing mental health conditions among health care workers and the community during the COVID-19 pandemic. Results: Mental health conditions among community people included lower psychological well-being, anxiety, depression/depressive symptoms, fear, stress including acute stress reaction; psychological distress; COVID-19 related stress; and stress symptoms, and grief among patients’ family members. Among health care workers, mental health conditions were identified as anxiety, depression/depressive symptoms, fear, insomnia, poor sleep quality, isolation, emotional disturbances, moral injury, post-traumatic disorder, burnout, and secondary traumatization. Conclusion: Findings of this integrative review were expected to provide evidence of the mental health conditions among groups of uninfected persons and describe how they managed their health during the pandemic. Identifying mental health conditions among community people and health care workers is essential to prevent adverse psychological conditions. Mental health support practices should be made accessible to at risk persons and discriminatory actions toward frontline workers should be eliminated. Various strategies are proposed to manage mental health conditions such as rapid access to counseling, accessing information from reliable sources, maintaining healthy lifestyle and strengthening adequate coping patterns.

Extracellular histones are a damage-associated molecular pattern (DAMP) involved in the pathogenesis of various diseases. The mechanisms of histone-mediated injury in certain organs have been extensively studied, but an understanding of the pathophysiological role of histone-mediated injury in multiple organ injury remains elusive. To elucidate this role, we systemically subjected C57BL/6 mice to various doses of histones and performed a chronological evaluation of the morphological and functional changes in the lungs, liver, and kidneys. Notably, histone administration ultimately led to death after a dose-dependent aggravation of multiple organ injury. In chronological studies, pulmonary and hepatic injuries occurred within 15 minutes, whereas renal injuries presented at a later phase, suggesting that susceptibility to extracellular histones varies among organs. Histones bound to pulmonary and hepatic endothelial cells immediately after administration, leading to endothelial damage, which could be ameliorated by pretreatment with heparin. Furthermore, release of another DAMP, high-mobility group protein box 1, followed the histone-induced tissue damage, and an antibody against the molecule ameliorated hepatic and renal failure in a late phase. These findings indicate that extracellular histones induce multiple organ injury in two progressive stages-direct injury to endothelial cells and the subsequent release of other DAMPs-and that combination therapies against extracellular histones and high-mobility group protein box 1 may be a promising strategy for treating multiple organ injury.

In forensic science, DNA mixture interpretation is traditionally based on a binary model, which does not account for peak-height information in DNA profiles. In recent years, some countries have adopted a continuous model in which peak heights are used and stochastic effects are considered to enable rigorous calculation of likelihood ratios. However, this model requires certain biological parameters which affect the expected allelic and stutter peak heights. In this paper, we focused on estimating the distribution of the stutter ratio (SR) in 15 short tandem repeat loci in relation to the allele repeat number. We estimated the SR values of 234 single-source DNA samples by using a commercially available kit. In all loci except for D8S1179, D21S11, and D2S1338, a simple log-normal distribution model was fitted to the variability of SR. For D21S11, we developed a new distribution model in which distinct log-normal distributions between complete and incomplete repeat units are used (a separate log-normal distribution model). For D8S1179 and D2S1338, we developed another new distribution model that mixes two log-normal distributions to explain two types of repeat structures appearing within the same number of allele repeats. These two models were fitted to the observed SR values more accurately than the simple log-normal distribution model. We expected these new SR models to be applied to DNA mixture interpretation based on a continuous model.

Kupffer cells (KCs) are key players in maintaining tissue homeostasis and are involved in various liver diseases. However, the roles of KCs in the pathogenesis of cholangiopathy are largely unknown. We aimed to investigate the precise roles of KCs in both the progression and regression phases of the 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced cholangiopathy model. In the early phase of DDC-induced cholangiopathy, the number of KCs significantly increased over time. Moreover, KCs were associated with abnormal phenotypic changes in other liver cells, such as hepatocytes, biliary epithelial cells, liver sinusoidal endothelial cells, and hepatic stellate cells. In contrast, KC depletion by clodronate administration suppressed the progression of the disease, and maintained the phenotypes of other cells. In the regression phase, the numbers of KCs significantly decreased, and the cells redifferentiated to their quiescent state. In contrast, KC depletion delayed the recovery of cells by maintaining other liver cells in an active state. These findings suggest that KCs play detrimental roles in the progression phase; however, they are beneficial in the regression phase by mediating interactions between other liver cells. Our data provide new insights into the roles of KCs in the pathogenesis of cholangiopathy.

Bilateral spontaneous pneumothorax secondary to disease is rare and seldom encountered in forensic autopsies; however, traumatic bilateral pneumothorax occurs often. Herein, we present a forensic case involving a 50-year-old woman who died 4 days after ingesting a wristwatch. Postmortem computed tomography and autopsy findings demonstrated that the wristwatch was lodged at the pharyngoesophageal junction, that she had a bilateral pneumothorax unaccompanied by any thoracic wound, and that macular hemorrhagic lesions on the lung surfaces were responsible for the pneumothorax. A histological examination of the macular lesions revealed that they were aspiration pneumonia foci with many birefringent foreign materials. Furthermore, a necrotic process secondary to aspiration pneumonia with a one way check-valve hyperinflation caused by foreign materials in the bronchioles was the most probable pathogenesis of her pneumothorax. To our knowledge, this is the first reported case of a bilateral secondary spontaneous pneumothorax caused by a large foreign body at the pharyngoesophageal junction leading to death.

Objectives An ectopic cervical thymus (ECT) is regarded as a rare congenital anomaly; therefore, the optimal diagnostic and therapeutic strategy remains a debatable matter. We designed a study to elucidate the clinicopathological characteristics of ECTs in consecutive, unselected infant autopsies, to help guide case management. Methods We searched for ECTs in all of the 21 consecutive, unselected infant autopsy cases performed at our institution over a period of 3 years, and all ECT consensus diagnoses were confirmed by histological examination. The following clinical characteristics were evaluated in cases with ECTs: age, gender, birth week and weight, clinical symptoms due to the ECT(s), position on discovery of death, cause of death, ECT contribution to the cause of death, and concomitant congenital disorders. The anatomical features evaluated included the location, number, size, color, shape, and margins of the ECTs, and the presence of a mediastinal thymus. Histological findings of the ECT(s) and the mediastinal thymus were compared within each individual. Fusion of the parathyroid and the ECT was also investigated histologically. Spearman's rank correlation coefficient (ρ) and the corresponding P value were calculated to determine if there was an association between ECT diameter and age. Results We detected 10 ECT lesions in seven cases (33%) among the 21 infant autopsy cases. The ECT cases involved five boys and two girls, with ages ranging from 1 day to 4 months. There were no reports of a positive family history of sudden death or antemortem clinical symptoms due to ECT in any of the cases. The ECTs were considered incidental regarding the cause of death, with the exception of one case that was extremely rare. Most ECTs were localized to the inferior thyroid, ranging from 0.4 to 1.9 cm in size. Size demonstrated a significant negative correlation with age (ρ = −0.75 and P = 0.034). Conclusions This study revealed that ECT is an essentially benign anomaly that occurs frequently during the development of the thymus, and may disappear over the first few years of life. These results suggest a conservative approach to the management of ECTs would be appropriate.

An ectopic cervical thymus is a rare congenital anomaly that can be located anywhere along the developmental pathway of thymic descent. Most lesions manifest as a cystic mass and have an indolent course. Two fatal cases associated with ectopic cervical thymus in the form of a solid mass are presented in conjunction with a review of the clinicopathological characteristics of the solid form. This report emphasizes the importance of considering a diagnosis of ectopic cervical thymus in infants with neck masses, with or without obstructive symptoms, to prevent possibly fatal outcomes.

Compounds which can be formed over the course of roasting coffee beans were investigated and isolated. One of these compounds was identified as 3-hydroxy-6-methylpyridine (3,6-Py). 3,6-Py and the coffee prepared from light-roasted coffee beans which contain this compound tended to suppress increases in plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities induced by carbon tetrachloride in mice, indicating that 3,6-Py formed during the roasting of coffee beans may be able to mitigate liver injury. The amounts of 3,6-Py were higher in French-roasted than light-roasted coffee beans of the Brazil Santos and Colombia Excelso varieties, suggesting that this compound might be produced under a more severe roasting condition. However, suppressive activity against liver injury was stronger in coffee from light-roasted than French-roasted beans. As the amounts of chlorogenic acid, which is known to have hepatoprotective activity, were higher in coffee from the light-roasted than French-roasted beans, stronger hepatoprotective activity in the coffee from light-roasted beans might be mainly concerned with its higher content of chlorogenic acid.

The pathogenesis of renal impairment in chronic liver diseases (CLDs) has been primarily studied in the advanced stages of hepatic injury. Meanwhile, the pathology of renal impairment in the early phase of CLDs is poorly understood, and animal models to elucidate its mechanisms are needed. Thus, we investigated whether an existing mouse model of CLD induced by 3, 5-diethoxycarbonyl-1, 4-dihydrocollidine (DDC) shows renal impairment in the early phase. Renal injury markers, renal histology (including immunohistochemistry for tubular injury markers and transmission electron microscopy), autophagy, and oxidative stress were studied longitudinally in DDC- and standard diet-fed BALB/c mice. Slight but significant renal dysfunction was evident in DDC-fed mice from the early phase. Meanwhile, histological examinations of the kidneys with routine light microscopy did not show definitive morphological findings, and electron microscopic analyses were required to detect limited injuries such as loss of brush border microvilli and mitochondrial deformities. Limited injuries have been recently designated as sublethal tubular cell injury. As humans with renal impairment, either with or without CLD, often show almost normal tubules, sublethal injury has been of particular interest. In this study, the injuries were associated with mitochondrial aberrations and oxidative stress, a possible mechanism for sublethal injury. Intriguingly, two defense mechanisms were associated with this injury that prevent it from progressing to apparent cell death: autophagy and single-cell extrusion with regeneration. Furthermore, the renal impairment of this model progressed to chronic kidney disease with interstitial fibrosis after long-term DDC feeding. These findings indicated that DDC induces renal impairment with sublethal tubular cell injury from the early phase, leading to chronic kidney disease. Importantly, this CLD mouse model could be useful for studying the pathophysiological mechanisms of sublethal tubular cell injury.

The tensile strength of α-Si 3 N 4 whiskers synthesized by reacting amorphous Si 3 N 4 and TiO 2 at 1490°C under a N 2 pressure of 700 torr was measured using a microbalance, and the diameter dependence of the strength was investigated. The Si 3 N 4 whiskers had diameters of 0.04 and 0.8 μm and dominant [1011] and [1010] growth directions. Chemical analysis showed that they contained Ti and O impurities. The tensile strength of six Si 3 N 4 whiskers increased from 17 to 59 GPa with decreasing whisker diameter.

The flexural strength of porous Si{sub 3}N{sub 4} ceramics with a variety of microstructures and porosities were evaluated, and the effect of microstructure on the flexural strength was investigated to obtain machinable Si{sub 3}N{sub 4} ceramics having both high strength and high thermal shock resistance. Porous Si{sub 3}N{sub 4} having three types of microstructure, consisting of (1) only spherical grains, (2) combinations of spherical and columnar grains, and (3) only columnar {beta}-grains connected randomly in three dimensions, were readied as specimens. Their mean pore diameters and porosities were 0.2 to 0.3 {mu}m and 8% to 59%, respectively. The flexural strength of the porous Si{sub 3}N{sub 4} (3) was much larger than that of the porous Si{sub 3}N{sub 4} having the other microstructures, and the maximum flexural strength was 455 MPa at a porosity of 38.3%. The thermal shock resistance ({Delta}T), which was determined by a water quench test, of porous SI{sub 3}N{sub 4} with such microstructure and a porosity of 50% was 980 K. All of the porous Si{sub 3}N{sub 4} (3) was easily machined with cemented carbide drills.

Liver sinusoidal endothelial cells (LSECs) are involved in the transport of nutrients, lipids, and lipoproteins, and LSEC injury occurs in various liver diseases including nonalcoholic fatty liver disease (NAFLD). However, the association between LSEC injury and NAFLD progression remains elusive. Accordingly, in this study, we aimed to elucidate the precise role of LSEC in the pathophysiology of NAFLD using two different mouse models, namely the choline-deficient, L-amino acid-defined and high-fat diet models. Administration of these diets resulted in liver metabolic dysregulation mimicking human NAFLD, such as steatosis, ballooning, lobular inflammation, and fibrosis, as well as central obesity, insulin resistance, and hyperlipidemia. LSEC injury appeared during the simple steatosis phase, and preceded the appearance of activated Kupffer cells and hepatic stellate cells (HSCs). These results indicate that LSEC injury may have a 'gatekeeper' role in the progression from simple steatosis to the early nonalcoholic steatohepatitis (NASH) stage, and LSEC injury may be necessary for the activation of Kupffer cells and HSCs, which in turn results in the development and perpetuation of chronic liver injuries. Taken together, our data provide new insights into the role of LSEC injury in NAFLD/NASH pathogenesis., Advance online publication 27 July 2015

Aluminum-silicon carbide composite heat spreaders having high thermal conductivity were successfully fabricated by a hot-forging technique, and the effect of an interfacial reaction between Al and SiC on the thermal conductivity of the composites was quantified by X-ray diffraction and theoretical calculations. Al-SiC composites with SiC dispersions were fabricated by forging pure Al-SiC powder compacts at a variety of temperatures, under a high pressure of 900MPa. At forging temperatures below the melting point of Al, porous specimens were obtained, resulting in low thermal conductivity. In contrast, fully-densified specimens having high thermal conductivity were obtained at forging temperatures above the melting point. The interfacial reaction between the Al matrix and the SiC particles produced an interfacial reaction layer of Al4C3, the thickness of which increased with increasing forging temperature. Calculation of the theoretical thermal conductivities of the composites using the Hasselman's model suggests that the increased forging temperature decreases the thermal barrier conductance of the Al-SiC interface, decreasing the overall thermal conductivity of the Al-SiC composites.

The grain size distributions (diameter and aspect ratio) of porous Si3N4 ceramics composed of elongated β-Si3N4 grains were evaluated statistically, and their effect on the pore size distribution and the flexural strength of the porous Si3N4 was investigated. Porous Si3N4 ceramics having porosities of 27 to 43% and median pore diameters of 0.56 to 0.96 μm were used as specimens. The grain diameter distribution was well correlated to the pore size distribution of the porous Si3N4 ceramics. We concluded that the strength of the porous Si3N4 ceramics increased with increasing grain length of β-Si3N4 as well as with decreasing porosity.

In this report, the wettability of molten Al alloys with SiC powder is discussed using mercury porosimetric analysis. Al-SiC powder compacts with a composition of SiC-30mass%Al are used as the starting materials. Wettability can be evaluated from their pore size distribution after heating. In the pure Al-SiC system, the increase in temperature increases the open-pore size and the open-porosity of specimens, resulting in high wettability. The addition of a slight amount of Mg to Al significantly increases the wettability. We conclude that the decrease in surface tension of molten Al alloys is seriously effective to improve the wettability.

The effect of metal oxides addition in the preparation of Si 3 N 4 whiskers by reacting amorphous Si 3 N 4 and metal oxides was investigated experimentally and thermodynamically. The compacted bodies of amorphous Si 3 N 4 and a variety of metal oxides were heated at 1490°C, 700 torr in N 2 . Of all the metal oxides, the addition of TiO 2 , Cr 2 O 3 and Fe 2 O 3 produced a silicide and nitrides such as TiN, CrN and FeSi in the compacted bodies after heating, and produced large mass loss of the compacted bodies. α-Si 3 N 4 whiskers were formed in only the TiO 2 addition system, and a Ti impurity was included in the whiskers. Thermodynamic calculation indicated that the decrease in Si 3 N 4 amount and the increase in SiO (gas) amount with increasing temperature were pronounced with the three systems, and that TiO gas was formed in the system of TiO 2 addition. From these results, it was concluded that high affinity of metal atoms in additives with Si 3 N 4 resulted in high partial pressure of SiO gas for nucleation of Si 3 N 4 whiskers. Furthermore, it was presumed that nitridation of the transported TiO gas and the condensation of SiO gas on the resulting TiN nucleus produced Si 3 N 4 whiskers.

Silicon nitride (Si3N4) whiskers were coated on a porous Si3N4 substrate, which was coated with SiO2-Al2O3-Y2O3 oxides, by gas phase processing using amorphous Si3N4 and TiO2 powders as source materials. Coating was carried out in the interval 1350-1550°C in N2. At temperatures below the melting point of the oxides, α-Si3N4 whiskers of high aspect ratio were coated with weak adhesion to the substrate. At temperatures above the melting point, β-Si3N4 whiskers with diameters of 0.02 to 0.07μm (low aspect ratio) were coated with strong adhesion to the substrate. When the Si3N4 substrates coated with the β-Si3N4 whiskers were used as membrane filters, it could separate particles as fine as 0.05μm in diameter.

The separation–permeation performance of porous silicon nitride (Si3N4) ceramics (consisting of columnar grains connected at random in three dimensions) as membrane filters was evaluated, and compared with commercial Al2O3 membranes having a three-layer structure. Si3N4 membranes separate particles with diameters much less than their pore diameters. The permeability of Si3N4 membranes with separability values the same as those of the Al2O3 membranes was about 1.3–2.4 times as large as the Al2O3 membranes. Dead-end filtration examination, using Al2O3 particles with a particle size distribution, indicated that the Si3N4 membrane filtration mechanism obeyed the cake filtration mechanism although the particle size was smaller than the pore size of the Si3N4 membranes.

In forensic genetics, increasing the number of short tandem repeat (STR) loci is an efficient strategy to achieve a high likelihood ratio (LR) for sibship determination. However, as the number of loci increases, the effect of linkage among the loci may become more pronounced. Hence, we evaluated the effect of linkage on sibship determination when analyzing multiple loci including linked loci. We investigated LR value variation in two linked loci by changing the recombination rate and allele frequencies. We then compared LR values with values calculated without considering linkage, using computationally generated genotypes of sibling pairs. These results suggested that the effect of linkage on LR values in sibship determination is affected by the identity by state of the loci, allele frequencies, and number of loci. Therefore, linkage must be considered to calculate rigorous LR values.

Amorphous Si3N4/TiO2 compacted bodies were heated at 1490°C, for 1 to 10 hr under N2 pressures of 0.92 and 1000 atm, and the effect of N2 pressure on the resulting grain refining was investigated, to clarify the role of TiO2 in the grain-refined mechanism. Thermodynamic calculation performed prior to experiments indicated that high N2 pressure inhibited the formation of SiO gas and new formation of Si3N4 by its re-nitridation. Crystallized phases after heating were α-Si3N4, Si2N2O and TiN. Although both N2 pressures formed the fine grains having a diameter of about 30 nm, high pressure accelerated the grain refining and crystallization of amorphous Si3N4 to a-Si3N4. From these results, the fine grains were considered to be formed not through re-nitridation of SiO gas but through crystallization of amorphous Si3N4.

Carbon fibre reinforced SiC matrix composites (C/SiC composites) were fabricated using an electrodeposition/sintering method and the control of properties such as flexural strength. Young's modulus and thermal expansion coefficient was investigated in order to fabricate C/SiC-based functionally gradient materials. By means of choosing the condition of electrodeposition and sintering, C/SiC composites with volume fraction of fibre (Vf) ranging from 45 to 78% were fabricated. Maximum flexural strength and Young's modulus were 185 MPa and 47.5 GPa with Vf of 75%, but both properties decreased with the decrease in Vf. Conversely, the thermal expansion coefficient increased with the decrease in Vf; the value varied from 0.2 to 2.75 × 10−6K−1.

Background Little is known about the relationship between splenic arteriolar hyaline and cause of death. The purpose of this retrospective study was to evaluate the clinicopathological significance of splenic arteriolar hyaline in autopsy cases and estimate the applicability of hyaline for diagnosing the cause and rapidity of death. Methods Archival data and histological slides from 82 cases were reviewed retrospectively. One section of each spleen was evaluated microscopically. The tinctorial pattern of splenic arteriolar hyaline was examined with Heidenhain’s Azan trichrome stain, and the relationships between this pattern and age, cause of death, and rapidity of death were investigated. Results Fifty-four cases demonstrated hyaline change, with 3 different tinctorial patterns: red, blue, and a combination of red and blue. The 3 patterns coexisted in various proportions in each tissue section. Frequency of the blue pattern increased with age (P P Conclusions Estimation of splenic arteriolar hyaline with Heidenhain’s Azan trichrome stain is useful for assessment of the cause and rapidity of death. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1132441651796836

Pituitary abscess is a rare disease presenting with nonspecific clinical symptoms, and diagnosis is often difficult. This disease is potentially life-threatening, but most cases have a chronic and indolent course. We report a case of a 60-year-old man with a pituitary abscess associated with pituitary adenoma who died 5 days after the onset of clinical symptoms without a definitive diagnosis. Postmortem computed tomography and autopsy findings revealed a sellar mass with cystic change and extension toward the optic chiasm. Histopathology of the lesion demonstrated an abscess with suppurative meningitis and encephalitis. The disturbance of the cardiac autonomic nervous system because of hypothalamus involvement was suggested as the cause of rapid progression and death. This case provides useful information for clinicians to avoid a lethal outcome.

We present here analytical data using the 15 STR typing (Identifiler) kit regarding heterozygote balance in experimental DNA samples including one or two persons. Surprisingly, the allelic imbalance was observed even in samples consisting of only one person but adequate DNA for the standard protocol. The variance of heterozygote balance was more expanded in two-person mixtures than in one-person samples. Therefore, it is not suitable to use allelic peak heights/areas for estimating the genotypes of the contributors such as the quantitative analysis. We also reevaluated the effectiveness of qualitative analysis by simulation, i.e. consideration of the probability of all possible genotype combinations from the typing results of a mixed DNA sample. As demonstrated, the qualitative analysis using 15 STR loci is still extremely effective even in a mixture from two or three individuals.

Carbon nanotubes (CNT) are predicted to have an extremely high thermal conductivity along the tube axis of 6600 W/mK (Berber, 2000) while experimental results (Fujii et al., 2005; Kim et al., 2001) have produced values of 2000~3000 W/mK. However, only a few studies have investigated CNTs for use as thermal interface materials (TIMs) (Biercuk et al., 2002; Liu et al., 2004; Huang et al., 2005). In this study, we focus on the heat-release structure of a central processing unit (CPU). Figure 1 shows the schematic diagram of the typical heatrelease structure.

The effect of interfacial reactions between Al and SiC on the thermal conductivity of SiC-particle-dispersed Al-matrix composites was investigated by X-ray diffraction and transmission electron microscopy (TEM), and the thermal barrier conductance (h c ) of the interface in the Al-SiC composites was quantified using a rule of mixture regarding thermal conductivity. Al-SiC composites with a composition of Al (pure Al or Al-11 vol% Si alloy)-66.3 vol% SiC and a variety of SiC particle sizes were used as specimens. The addition of Si to an Al matrix increased the thermal barrier conductance although it decreased overall thermal conductivity. X-ray diffraction showed the formation of Al 4 C 3 and Si as byproducts in addition to Al and SiC in some specimens. TEM observation indicated that whiskerlike products, possibly Al 4 C 3 , were formed at the interface between the SiC particles and the Al matrix. The thermal barrier conductance and the thermal conductivity of the Al-SiC composites decreased with increasing Al 4 C 3 content. The role of Si addition to an Al matrix was concluded to be restraining an excessive progress of the interfacial reaction between Al and SiC.

X-Ray stress measurement was applied to TiC and SiC monolithic films and TiC/SiC composite films coated by CVD process on graphite substrates. Textures of films were examined by the X-ray diffraction method. TiC coating had preferential growth of the (2 2 0) plane. SiC coating had preferential growth of the (1 1 1) plane. TiC/SiC composite coating showed a strong texture of the (2 2 0) plane perpendicular to the substrate surface. The diffractions from TiC (3 3 1) and SiC (3 3 1) planes by Fe-Kα characteristic X-rays are suited for X-ray residual stress measurement in thin films. In TiC/SiC composite coating, X-ray diffraction profiles from the TiC phase and SiC phase overlap. These line profiles were separated into TiC and SiC line profiles by the modified DFP method. Phase stresses in the TiC phase and SiC phase in TiC/SiC composite coating showed a triaxial stress state. The measured residual stress of the TiC phase is tensile and that of the SiC phase is compressive. Although the surface residual stress in SiC monolithic coating with thicknesses below 30μm was compressive, the residual stress was tensile for thick coating, and increased with increasing film thickness.

Oxidation-resistant coating using chemical vapor deposition on continuous fiber reinforced ceramics having lower thermal expansion coefficient (α) than the coated layer (SiC) was studied. A SiC-fiber reinforced TiC matrix composite (SiC/TiC composite, α=5.6×10-6K-1) was used as a substrate and the TiC-SiC system was chosen as a coating. The CVD was carried out in TiCl4-SiCl4-CH4-H2 system at deposition temperature of 1350°C and total gas pressure of 60 Torr. Compositionally gradient TiC-SiC layers were formed by stepwise change of the Ti/(Ti+Si) ratio in the feed gas. Peeling occurred along the edges of the coating in the case of SiC coating, but it did not occur at all in a TiC-SiC coating with an optimum gradient composition. These results agreed with the thermal stress analysis using F. E. M.

Fracture toughness (KIC) of CVD⋅TiC-SiC composites with columnar structure was measured by the indentation microfracture method. In order to explain the resulting high fracture toughness, residual stress in the composites was measured by the X-ray diffraction method (2θ-sin2Ψ method). Crack deflection was observed in both surfaces perpendicular and parallel to columnar structure of TiC-SiC composites, more pronounced with the latter. The KIC values were about three to four times as large as that of monolithic SiC or TiC, and were about twice as large as sinterd TiC-SiC composites with TiC-dispersed type of structure. It was presumed that the residual stress in the CVD⋅TiC-SiC composites was much larger than that in monolithic SiC or TiC, and the values parallel to the columnar structure of the composites was larger than that perpendicular. From above result, it was considerd that the high fracture toughness of CVD⋅TiC-SiC composites was achieved by crack deflection, the effect of which depended on the residual stress in the composites.

Composites with several compositions in TiC-SiC system were fabricated by chemical vapor deposition and several properties were measured. The CVD conditions used were, TiCl4-SiCl4-CH4-H2 system, deposition temperature of 1350°C and total gas pressure of 60Torr. The TiC-SiC composites with various compositions were fabricated by stepwise change in the Ti/(Ti+Si) ratio in the feed gas on the basis of thermodynamic calculation for the system. The obtained composites were fully dense with columnar structure perpendicular to the substrate plane and had (220) orientation on parallel there to. Thermal expansion coefficients of the TiC-SiC composites parallel to substrate ranged from 4.5 to 7.4×10-6K-1 and Young's Modulus perpendicular to the substrate ranged from 220 to 467GPa depending on the composition. These measured values agreed with that calculated from some rules of mixture in composite.