Topkapı Sarayı Müzesinde Türk saatleri

Taha Toros Arşivi, Dosya No: 114-Müzelerİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Formation of an Ultracarbonaceous Antarctic Micrometeorite through Minimum Aqueous Alteration in a Small Porous Icy Body

A comprehensive study of the organic chemistry and mineralogy of an ultracarbonaceous micrometeorite (UCAMM D05IB80) collected from near the Dome Fuji Station, Antarctica, was carried out to understand the genetic relationship among organic materials, silicates, and water. The micrometeorite is composed of a dense aggregate of ∼5 µm-sized hollow ellipsoidal organic material containing submicrometer-sized phases such as glass with embedded metal and sulfides (GEMS) and mineral grains. There is a wide area of organic material (∼15 × 15 μm) in its interior. Low-Ca pyroxene is much more abundant than olivine and shows various Mg/(Mg + Fe) ratios ranging from ∼1.0 to 0.78, which is common to previous works on UCAMMs. By contrast, GEMS grains in this UCAMM have unusual chemical compositions. They are depleted in both Mg and S, which suggests that these elements were leached out from the GEMS grains during very weak aqueous alteration, without the formation of phyllosilicates. The organic materials have two textures—smooth and globular with an irregular outline—and these are composed of imine, nitrile and/or aromatic nitrogen heterocycles, and amide. The ratio of nitrogen to carbon (N/C) in the smooth region of the organics is ∼0.15, which is five times higher than that of insoluble organic macromolecules in types 1 and 2 carbonaceous chondritic meteorites. In addition, the UCAMM organic materials are soluble in epoxy and are thus hydrophilic; this polar nature indicates that they are very primitive. The surface of the material is coated with an inorganic layer, a few nanometers thick, that consists of C, O, Si, S, and Fe. Sulfur is also contained in the interior, implying the presence of organosulfur moieties. There are no isotopic anomalies of D, 13C, or 15N in the organic material. Interstellar photochemistry alone would not be sufficient to explain the N/C ratio of the UCAMM organics; therefore, we suggest that a very small amount of fluid on a comet must have been necessary for the formation of the UCAMM. The GEMS grains depleted in Mg and S in the UCAMM prove a very weak degree of aqueous alteration; weaker than that of carbonaceous chondrites. Short-duration weak alteration probably caused by planetesimal shock locally melted cometary ice grains and released water that dissolved the organics; the fluid would likely have not mobilized because of the very low thermal conductivity of the porous icy body. This event allowed the formation of the large organic puddle of the UCAMM, as well as organic matter sulfurization, formation of thin membrane-like layers of minerals, and deformation of organic nanoglobules.アクセプト後にタイトル・アブストラクト等変更あり、著者最終稿は変更前のタイトル"Formation of an Ultracarbonaceous Antarctic Micrometeorite through Minimum Aqueous Alteration in a Small Porous Icy Body"This work was supported by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Culture, Sports, Science and Technology (No. 22224010, PI: H. Nagahara). The STXM facility at the beamline 5.3.2.2, ALS, is supported by the Department of Energy, Basic Energy Sciences Program

Sugar Scrub Effects on Skin Barrier Function and Heat Retention in Low Birth Weight Infants

Objective: This investigation sought to compare changes in body heat after using a sugar scrub to bathe lowbirth weight infants (< 2,500 g), compared with those bathed using conventional baby soap, and to evaluatethe relationship between skin barrier function and changes in body heat.Design: Non-Randomized clinical trialsSetting: A neonatal intensive care unit in a university hospital in JapanParticipants: 22 Low birth weight infants for whom bathing was permittedMethods: Sebum quantity and skin temperature were each measured before and after bathing for a control groupbathed with conventional baby soap and a group bathed with a sugar scrub skin care product. Ethical approvalfor this study was obtained from Aino university of Ethics committee review board (Approval number/27)Results: The results demonstrated that both sebum quantity and skin temperature increased significantly afterbathing in the sugar scrub group compared with the baby soap group.Conclusion: Increases in sebum quantity are thought to influence the normal barrier function of skin and to helpretain skin temperature. This study suggests that the use of this skin care product can be expected to effectivelyhelp maintain body temperature in low birth weight infants, who are prone to low body temperature

Organic chemical variation between hydrous and anhydrous Antarctic micrometeorites

第6回極域科学シンポジウム[OA] 南極隕石11月17日（火）　国立国語研究所 2階 講

Enhanced Nogo-P3 amplitudes of mothers compared with non-mother women during an emotional Go/Nogo task

Background: It is known that emotion regulatory responses of humans are changed by the experiences they have, but in particular, they are changed by becoming a mother. A recent study has found how a woman&apos;s emotion regulatory response to a child&apos;s crying changes after becoming a mother. However, mothers&apos; emotion regulatory responses other than those to children and the association between emotion regulatory response and parental stress are still unknown. Methods: Eighteen healthy Japanese females (nine mothers and nine non-mothers) participated in the experiment. They performed an emotional Go/Nogo task, with facial expressions of others (angry, happy, and neutral faces) used as emotional stimuli. The percentage of correct responses, response time, and event-related potentials (ERPs) during the task was measured. Results: This comparison revealed that the mother group had a larger P3 (Nogo-P3) amplitude than the non-mother group when Nogo trials were held. This indicates that in mothers, there was greater activation of the behavioral inhibition-related brain areas than in non-mother women when they inhibited inappropriate behavior following recognition of facial expressions of others. In addition, in the mother group, there was a negative correlation between parental stress levels and Nogo-P3 amplitudes evoked by angry faces. This suggests that there is a relation between the level of parental stress of mothers and their emotion regulatory responses to angry faces. Conclusions: Our results demonstrate that mothers&apos; emotion regulatory processes may differ from those of non-mothers in response, not only to a child&apos;s crying but also to expressions of emotions by others, and also suggest that the inhibitory recognition activity of mothers can be affected by parental stres

A serine proteinase from the sarcoplasmic fraction of red sea bream Pagrus major is possibly derived from blood

Collagen degradation is known to be involved in the post mortem tenderization of fish muscle. A serine proteinase that is assumed to be related to collagen degradation after fish death was purified from the sarcoplasmic fraction of red sea bream Pagrus major by ammonium sulfate fractionation and column chromatography on Sephacryl S-300, Q Sepharose and Phenyl Sepharose CL-4B. The enzyme hydrolyzed gelatin and was obtained as a protein band of approximately 38 kDa upon sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions. The N-terminal amino acid sequence of the enzyme was determined for 32 residues. A protein that had the same N-terminal amino acid sequence as the enzyme for ten residues was purified from the serum of red sea bream and showed the same characteristics as the enzyme. Therefore, it is suggested that the serine proteinase migrates from the blood to muscle and degrades muscle proteins after the death of the fish

Decreased circulating branched-chain amino acids are associated with development of Alzheimer’s disease in elderly individuals with mild cognitive impairment

BackgroundNutritional epidemiology has shown that inadequate dietary protein intake is associated with poor brain function in the elderly population. The plasma free amino acid (PFAA) profile reflects nutritional status and may have the potential to predict future changes in cognitive function. Here, we report the results of a 2-year interim analysis of a 3-year longitudinal study following mild cognitive impairment (MCI) participants.MethodIn a multicenter prospective cohort design, MCI participants were recruited, and fasting plasma samples were collected. Based on clinical assessment of cognitive function up to 2 years after blood collection, MCI participants were divided into two groups: remained with MCI or reverted to cognitively normal (“MCI-stable,” N = 87) and converted to Alzheimer’s disease (AD) (“AD-convert,” N = 68). The baseline PFAA profile was compared between the two groups. Stratified analysis based on apolipoprotein E ε4 (APOE ε4) allele possession was also conducted.ResultsPlasma concentrations of all nine essential amino acids (EAAs) were lower in the AD-convert group. Among EAAs, three branched-chain amino acids (BCAAs), valine, leucine and isoleucine, and histidine (His) exhibited significant differences even in the logistic regression model adjusted for potential confounding factors such as age, sex, body mass index (BMI), and APOE ε4 possession (p &lt; 0.05). In the stratified analysis, differences in plasma concentrations of these four EAAs were more pronounced in the APOE ε4-negative group.ConclusionThe PFAA profile, especially decreases in BCAAs and His, is associated with development of AD in MCI participants, and the difference was larger in the APOE ε4-negative population, suggesting that the PFAA profile is an independent risk indicator for AD development. Measuring the PFAA profile may have importance in assessing the risk of AD conversion in the MCI population, possibly reflecting nutritional status.Clinical trial registration[https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000025322], identifier [UMIN000021965]