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This study focused on the equation of motion, hydrodynamic derivatives, and course stability with respect to ship maneuvering in a canal. Based on the potential theory, a consistent linearized equation of motion was derived when a ship maneuvers near the center line of a canal with a symmetrical cross-section and uniform length. In the new equation of motion, hydrodynamic derivatives for the lateral force and yaw moment with respect to ship heading angle ψ ( Y ψ , N ψ ) appear, which have not been considered in existing studies. Y ψ and N ψ are measured by captive tests using a container ship model in a canal model, and they are significant. Furthermore, the course stability criterion for ships in the canal was derived by considering the Y ψ and N ψ , and the course stability was investigated. As a result, we found that the effect of Y ψ and N ψ on course stability cannot be neglected when the water depth becomes shallower. In case of the studied container ship, the consideration of Y ψ and N ψ causes the ship to shift to the course stable direction.

In this study, we conducted turning tests with rudder angles ± 35 ∘ and ± 20 ∘ / 20 ∘ zig-zag maneuver tests in deep and shallow water using a model of a 3,600 TEU container ship called KCS. Through the comparison of these test results with the free-running test results of three other ships, the shallow-water effect on the maneuverability was investigated. The shallow-water effects obtained during the turning and zig-zag maneuvers are as follows: Turning: The advance ( A D ) decreases slightly when the water depth-to-ship draft ratio ( h / d ) is approximately 2.0 and increases significantly as the water depth decreases. The tactical diameter ( D T ) (up to h / d = 2.0 ) is approximately the same as that in deep water and becomes significantly larger when h / d becomes smaller than 2.0. Thus, there is a slight difference in the appearance of the shallow-water effects in A D and D T . Zig-zag maneuvers: The overshoot angle increases slightly near h / d = 2.0 compared with that in deep water and becomes significantly smaller as the water depth becomes shallower. The forward distance ( l 20 ), until reaching the heading + 20 ∘ / - 20 ∘ after steering, was approximately the same as that in deep water or decreased slightly, until approximately h / d = 2.0 . Furthermore, it increased as the water depth decreased. This is because the course stability of the ship deteriorated at approximately h / d = 2.0 .

BACKGROUND AND AIMS: Epigenetics is defined as mechanisms that regulate gene expression without base sequence alteration. One molecular basis is considered to be DNA cytosine methylation, which reversibly modifies DNA or chromatin structures. Although its correlation with epigenetic inheritance over generations has been circumstantially shown, evidence at the gene level has been limited. The present study aims to find genes whose methylation status directly correlates with inheritance of phenotypic changes. METHODS: DNA methylation in vivo was artificially reduced by treating rice (Oryza sativa ssp. japonica) seeds with 5-azadeoxycytidine, and the progeny were cultivated in the field for > 10 years. Genomic regions with changed methylation status were screened by the methylation-sensitive amplified polymorphysm (MSAP) method, and cytosine methylation was directly scanned by the bisulfite mapping method. Pathogen infection with Xanthomonas oryzae pv. oryzae, race PR2 was performed by the scissors-dip method on mature leaf blades. KEY RESULTS: The majority of seedlings were lethal, but some survived to maturity. One line designated as Line-2 showed a clear marker phenotype of dwarfism, which was stably inherited by the progeny over nine generations. MSAP screening identified six fragments, among which two were further characterized by DNA blot hybridization and direct methylation mapping. One clone encoding a retrotransposon gag-pol polyprotein showed a complete erasure of 5-methylcytosines in Line-2, but neither translocation nor expression of this region was detectable. The other clone encoded an Xa21-like protein, Xa21G. In wild-type plants, all cytosines were methylated within the promoter region, whereas in Line-2, corresponding methylation was completely erased throughout generations. Expression of Xa21G was not detectable in wild type but was constitutive in Line-2. When infected with X. oryzae pv. oryzae, against which Xa21 confers resistance in a gene-for-gene manner, the progeny of Line-2 were apparently resistant while the wild type was highly susceptible without Xa21G expression. CONCLUSIONS: These results indicated that demethylation was selective in Line-2, and that promoter demethylation abolished the constitutive silencing of Xa21G due to hypermethylation, resulting in acquisition of disease resistance. Both hypomethylation and resistant trait were stably inherited. This is a clear example of epigenetic inheritance, and supports the idea of Lamarckian inheritance which suggested acquired traits to be heritable.

An equivalent single rudder (ESR) model is presented for maneuvering simulations of twin-propeller and twin-rudder ships within the framework of the maneuvering modeling group (MMG) method Yasukawa (J Marine Sci Technol 20:37–52, 2015). It eliminates the complexity of a mathematical model by treating a port and starboard rudders as a single rudder located at the center of the ship hull. Specifically, an expression for the rudder force is presented using the ESR model. As examples, the results of captive model tests for a twin-screw ferry in deep and shallow water and the analysis results are presented, and maneuvering simulations are conducted using the hydrodynamic force coefficients obtained from the analysis. The simulation results of turning and zig–zag maneuvers agree with the results of free-running model tests, in regard to practical application. The maneuvering simulation method using the ESR model is validated for twin-propeller and twin-rudder ships in deep and shallow water.

In this randomized trial involving patients with mild cognitive impairment, vitamin E did not reduce the rate of progression to Alzheimer's disease. Although an initial benefit of donepezil was observed during the first year, over the course of the three-year study the rate of progression to Alzheimer's disease was similar in patients treated with donepezil and those treated with placebo. The side effects of donepezil included diarrhea, nausea, muscle cramps, and insomnia. In patients with mild cognitive impairment, vitamin E did not reduce the rate of progression to Alzheimer's disease. Over the course of the three-year study the rate of progression to Alzheimer's disease was similar in patients treated with donepezil and those treated with placebo. Mild cognitive impairment represents a transitional state between the cognitive changes of normal aging and the earliest clinical features of Alzheimer's disease. 1 Amnestic mild cognitive impairment refers to the subtype that has a primary memory component, either alone (single domain) or in conjunction with other cognitive-domain impairments (multiple domain), but of insufficient severity to constitute dementia. 2 – 6 Previous research has shown that the rate of progression to clinically diagnosable Alzheimer's disease is 10 to 15 percent per year among persons who meet the criteria for the amnestic form of mild cognitive impairment, in contrast to a rate of 1 to . . .

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disorder most commonly associated with repetitive traumatic brain injury (TBI) and characterized by the presence of neurofibrillary tangles of tau protein, known as a tauopathy. Currently, the diagnosis of CTE can only be definitively established postmortem. However, a new positron emission tomography (PET) ligand, [ 18 F]T807/AV1451, may provide the antemortem detection of tau aggregates, and thus various tauopathies, including CTE. Our goal was to examine [ 18 F]T807/AV1451 retention in athletes with neuropsychiatric symptoms associated with a history of multiple concussions. Here we report a 39-year-old retired National Football League player who suffered 22 concussions and manifested progressive neuropsychiatric symptoms. Emotional lability and irritability were the chief complaints. Serial neuropsychological exams revealed a decline in executive functioning, processing speed and fine motor skills. Naming was below average but other cognitive functions were preserved. Structural analysis of longitudinally acquired magenetic resonance imaging scans revealed cortical thinning in the left frontal and lateral temporal areas, as well as volume loss in the basal ganglia. PET with [ 18 F]florbetapir was negative for amyloidosis. The [ 18 F]T807/AV1451 PET showed multifocal areas of retention at the cortical gray matter–white matter junction, a distribution considered pathognomonic for CTE. [ 18 F]T807/AV1451 standard uptake value (SUV) analysis showed increased uptake (SUVr⩾1.1) in bilateral cingulate, occipital, and orbitofrontal cortices, and several temporal areas. Although definitive identification of the neuropathological underpinnings basis for [ 18 F]T807/AV1451 retention requires postmortem correlation, our data suggest that [ 18 F]T807/AV1451 tauopathy imaging may be a promising tool to detect and diagnose CTE-related tauopathy in living subjects.

Lightly etched single-walled carbon nanotubes are chemically reacted to form rings. The rings appear to be fully closed as opposed to open coils, as ring-opening reactions did not change the structure of the observed rings. The average diameter of the rings was 540 nanometers with a narrow size distribution. The nanotubes in solution were modeled as wormlike polymer chains, yielding a persistence length of 800 nanometers. Nanotubes shorter than this length behave stiffly and stay nearly straight in solution. However, nanotubes longer than the Kuhn segment length of 1600 nanometers undergo considerable thermal fluctuation, suggesting a greater flexibility of these materials than is generally assumed.

Single, severe traumatic brain injury (TBI) which elevates CNS amyloid, increases the risk of Alzheimer’s disease (AD); while repetitive concussive and subconcussive events as observed in athletes and military personnel, may increase the risk of chronic traumatic encephalopathy (CTE). We describe two clinical cases, one with a history of multiple concussions during a career in the National Football League (NFL) and the second with frontotemporal dementia and a single, severe TBI. Both patients presented with cognitive decline and underwent [ 18 F]-Florbetapir positron emission tomography (PET) imaging for amyloid plaques; the retired NFL player also underwent [ 18 F]-T807 PET imaging, a new ligand binding to tau, the main constituent of neurofibrillary tangles (NFT). Case 1, the former NFL player, was 71 years old when he presented with memory impairment and a clinical profile highly similar to AD. [ 18 F]-Florbetapir PET imaging was negative, essentially excluding AD as a diagnosis. CTE was suspected clinically, and [ 18 F]-T807 PET imaging revealed striatal and nigral [ 18 F]-T807 retention consistent with the presence of tauopathy. Case 2 was a 56-year-old man with personality changes and cognitive decline who had sustained a fall complicated by a subdural hematoma. At 1 year post injury, [ 18 F]-Florbetapir PET imaging was negative for an AD pattern of amyloid accumulation in this subject. Focal [ 18 F]-Florbetapir retention was noted at the site of impact. In case 1, amyloid imaging provided improved diagnostic accuracy where standard clinical and laboratory criteria were inadequate. In that same case, tau imaging with [ 18 F]-T807 revealed a subcortical tauopathy that we interpret as a novel form of CTE with a distribution of tauopathy that mimics, to some extent, that of progressive supranuclear palsy (PSP), despite a clinical presentation of amnesia without any movement disorder complaints or signs. A key distinguishing feature is that our patient presented with hippocampal involvement, which is more frequently seen in CTE than in PSP. In case 2, focal [ 18 F]-Florbetapir retention at the site of injury in an otherwise negative scan suggests focal amyloid aggregation. In each of these complex cases, a combination of [ 18 F]-fluorodeoxyglucose, [ 18 F]-Florbetapir and/or [ 18 F]-T807 PET molecular imaging improved the accuracy of diagnosis and prevented inappropriate interventions.