Geological Research on the Bottom Sediments Sampled by the Fifth Japanese Antarctic Research Expedition

Results of soundings carried out during five Japanese Antarctic Research Expeditions are summarized. The bottom sediments collected by the 5th Expedition were analyzed concerning the grain size distribution, chemical composition, gravel composition, heavy mineral association, clay mineral composition and organic matters. The area studied is divisible into at least four sedimentary petrographic subprovinces on the basis of gravel composition, heavy mineral association and clay mineral composition. It is probable that these sediments were transported to the present sites from different sources without much sorting effects. The occurrence of trioctahedral illite in clay fraction may be the result of weak chemical weathering in the Antarctic region

Should We Still Subcategorize Helicobacter pylori-Associated Dyspepsia as Functional Disease?

Functional dyspepsia is a group of disorders featuring symptoms believed to be derived from the stomach and duodenum such as upper abdominal discomfort, pain, postprandial fullness and early satiety. A key diagnostic requisite is the absence of organic, metabolic, or systemic disorders to explain "dyspeptic symptoms." Therefore, when peptic ulcer diseases (including scars), erosive esophagitis and upper gastrointestinal malignancies are found at endoscopic examinations, the diagnosis of functional dyspepsia is excluded. One notable exception, however, is Helicobacter pylori infection. According to the Rome III definition, H. pylori infection is included in functional dyspepsia. This is an obvious deviation from the diagnostic principle of functional dyspepsia, since H. pylori infection is a definite cause of mucosal inflammation, which affects a number of important gastric physiologies such as acid secretion, gastric endocrine function and motility. The chronic persistent nature of infection also results in more dramatic mucosal changes such as atrophy or intestinal metaplasia, the presence of which in the esophagus (Barrett's esophagus) precludes the diagnosis of functional dyspepsia. Since careful endoscopic examination can diagnose reliably H. pylori infection not only in Japan but also in Western contries, it is now feasible and more logical to exclude patients with chronic gastritis caused by H. pylori infection as having dyspeptic symptoms. It is time to establish the Asian consensus to declare that H. pylori infection should be separated from functional dyspepsia

Transition from Positive to Neutral in Mutation Fixation along with Continuing Rising Fitness in Thermal Adaptive Evolution

It remains to be determined experimentally whether increasing fitness is related to positive selection, while stationary fitness is related to neutral evolution. Long-term laboratory evolution in Escherichia coli was performed under conditions of thermal stress under defined laboratory conditions. The complete cell growth data showed common continuous fitness recovery to every 2°C or 4°C stepwise temperature upshift, finally resulting in an evolved E. coli strain with an improved upper temperature limit as high as 45.9°C after 523 days of serial transfer, equivalent to 7,560 generations, in minimal medium. Two-phase fitness dynamics, a rapid growth recovery phase followed by a gradual increasing growth phase, was clearly observed at diverse temperatures throughout the entire evolutionary process. Whole-genome sequence analysis revealed the transition from positive to neutral in mutation fixation, accompanied with a considerable escalation of spontaneous substitution rate in the late fitness recovery phase. It suggested that continually increasing fitness not always resulted in the reduction of genetic diversity due to the sequential takeovers by fit mutants, but caused the accumulation of a considerable number of mutations that facilitated the neutral evolution

Stretchable and transparent electrodes based on in-plane structures

Stretchable electronics has attracted great interest with compelling potential applications that require reliable operation under mechanical deformation. Achieving stretchability in devices, however, requires a deeper understanding of nanoscale materials and mechanics beyond the success of flexible electronics. In this regard, tremendous research efforts have been dedicated toward developing stretchable electrodes, which are one of the most important building blocks for stretchable electronics. Stretchable transparent thin-film electrodes, which retain their electrical conductivity and optical transparency under mechanical deformation, are particularly important for the favourable application of stretchable devices. This minireview summarizes recent advances in stretchable transparent thin-film electrodes, especially employing strategies based on in-plane structures. Various approaches using metal nanomaterials, carbon nanomaterials, and their hybrids are described in terms of preparation processes and their optoelectronic/mechanical properties. Some challenges and perspectives for further advances in stretchable transparent electrodes are also discussed. © 2015 The Royal Society of Chemistry.open0

Knockdown of the Drosophila Fused in Sarcoma (FUS) Homologue Causes Deficient Locomotive Behavior and Shortening of Motoneuron Terminal Branches

Mutations in the fused in sarcoma/translated in liposarcoma gene (FUS/TLS, FUS) have been identified in sporadic and familial forms of amyotrophic lateral sclerosis (ALS). FUS is an RNA-binding protein that is normally localized in the nucleus, but is mislocalized to the cytoplasm in ALS, and comprises cytoplasmic inclusions in ALS-affected areas. However, it is still unknown whether the neurodegeneration that occurs in ALS is caused by the loss of FUS nuclear function, or by the gain of toxic function due to cytoplasmic FUS aggregation. Cabeza (Caz) is a Drosophila orthologue of human FUS. Here, we generated Drosophila models with Caz knockdown, and investigated their phenotypes. In wild-type Drosophila, Caz was strongly expressed in the central nervous system of larvae and adults. Caz did not colocalize with a presynaptic marker, suggesting that Caz physiologically functions in neuronal cell bodies and/or their axons. Fly models with neuron-specific Caz knockdown exhibited reduced climbing ability in adulthood and anatomical defects in presynaptic terminals of motoneurons in third instar larvae. Our results demonstrated that decreased expression of Drosophila Caz is sufficient to cause degeneration of motoneurons and locomotive disability in the absence of abnormal cytoplasmic Caz aggregates, suggesting that the pathogenic mechanism underlying FUS-related ALS should be ascribed more to the loss of physiological FUS functions in the nucleus than to the toxicity of cytoplasmic FUS aggregates. Since the Caz-knockdown Drosophila model we presented recapitulates key features of human ALS, it would be a suitable animal model for the screening of genes and chemicals that might modify the pathogenic processes that lead to the degeneration of motoneurons in ALS

(Table 1) Types of carbonate sediments and origin of carbonate constituents at DSDP Leg 57 Holes

Petrographic and mineralogical studies using optical and scanning electron microscopes and X-ray diffraction and X-ray microprobe analyzers on 137 samples of Pleistocene to Upper Cretaceous sediments at Sites 438 and 439 off northeast Honshu in northwest Pacific yielded the following major results: 1) Sites 438 and 439 are characterized by carbonate-free terrigenous and diatomaceous sediments throughout the Pleistocene to the Upper Cretaceous. However, carbonate concretions, thin limestone beds, and carbonate-cemented sandstones are sporadically intercalated. Moreover, terrigenous and diatomaceous sediments occasionally contain significant amounts of carbonates. 2) Carbonate minerals encountered include calcite, dolomite, ankerite, and siderite. Calcite and dolomite are either of authigenic or detrital origin. Biogenic calcite grains are not uncommon. Ankerite and siderite are of detrital origin. 3) Authigenic calcite ranges in chemical composition from high Mg calcite in the Pleistocene sediments to Fe calcite in the uppermost Oligocene sediments through FeMg calcite in the Miocene sediments. Composition is probably controlled by diagenetic alteration of initially precipitated high Mg calcite during burial. 4) Mg ions released from high Mg calcite during the transformation seem to cause dolomitization. 5) The transformation and dolomitization in the uppermost Oligocene sandstone were probably accelerated by the recharge of fresh or brackish water from the underlying subaerially formed conglomerate and/or from the nearby Oyashio ancient landmass