Effect of dental metal artifact conversion volume on dose distribution in head‐and‐neck volumetric‐modulated arc therapy

Purpose: During treatment planning for head‐and‐neck volumetric‐modulated arc therapy (VMAT), manual contouring of the metal artifact area of artificial teeth is done, and the area is replaced with water computed tomography (CT) values for dose calculation. This contouring of the metal artifact areas, which is performed manually, is subject to human variability. The purpose of this study is to evaluate and analyze the effect of inter‐observer variation on dose distribution. Methods: The subjects were 25 cases of cancer of the oropharynx for which VMAT was performed. Six radiation oncologists (ROs) performed metal artifact contouring for all of the cases. Gross tumor volume, clinical target volume, planning target volume (PTV), and oral cavity were evaluated. The contouring of the six ROs was divided into two groups, small and large groups. A reference RO was determined for each group and the dose distribution was compared with those of the other radiation oncologists by gamma analysis (GA). As an additional experiment, we changed the contouring of each dental metal artifact area, creating enlarged contours (L), reduced contours (S), and undrawn contours (N) based on the contouring by the six ROs and compared these structure sets. Results: The evaluation of inter‐observer variation showed no significant difference between the large and small groups, and the GA pass rate was 100%. Similar results were obtained comparing structure sets L and S, but in the comparison of structure sets L and N, there were cases with pass rates below 70%. Conclusions: The results show that the artificial variability of manual artificial tooth metal artifact contouring has little effect on the dose distribution of VMAT. However, it should be noted that the dose distribution may change depending on the contouring method in cases where the overlap between PTV and metal artifact areas is large

Somatic cell reprogramming-free generation of genetically modified pigs

Genetically modified pigs for biomedical applications have been mainly generated using the somatic cell nuclear transfer technique; however, this approach requires complex micromanipulation techniques and sometimes increases the risks of both prenatal and postnatal death by faulty epigenetic reprogramming of a donor somatic cell nucleus. As a result, the production of genetically modified pigs has not been widely applied. We provide a simple method for CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing in pigs that involves the introduction of Cas9 protein and single-guide RNA into in vitro fertilized zygotes by electroporation. The use of gene editing by electroporation of Cas9 protein (GEEP) resulted in highly efficient targeted gene disruption and was validated by the efficient production of Myostatin mutant pigs. Because GEEP does not require the complex methods associated with micromanipulation for somatic reprogramming, it has the potential for facilitating the genetic modification of pigs

Captive Bottlenose Dolphins (Tursiops truncatus) Spontaneously Using Water Flow to Manipulate Objects

Several terrestrial animals and delphinids manipulate objects in a tactile manner, using parts of their bodies, such as their mouths or hands. In this paper, we report that bottlenose dolphins (Tursiops truncatus) manipulate objects not by direct bodily contact, but by spontaneous water flow. Three of four dolphins at Suma Aqualife Park performed object manipulation with food. The typical sequence of object manipulation consisted of a three step procedure. First, the dolphins released the object from the sides of their mouths while assuming a head-down posture near the floor. They then manipulated the object around their mouths and caught it. Finally, they ceased to engage in their head-down posture and started to swim. When the dolphins moved the object, they used the water current in the pool or moved their head. These results showed that dolphins manipulate objects using movements that do not directly involve contact between a body part and the object. In the event the dolphins dropped the object on the floor, they lifted it by making water flow in one of three methods: opening and closing their mouths repeatedly, moving their heads lengthwise, or making circular head motions. This result suggests that bottlenose dolphins spontaneously change their environment to manipulate objects. The reason why aquatic animals like dolphins do object manipulation by changing their environment but terrestrial animals do not may be that the viscosity of the aquatic environment is much higher than it is in terrestrial environments. This is the first report thus far of any non-human mammal engaging in object manipulation using several methods to change their environment

On the origin and evolution of the asteroid Ryugu: A comprehensive geochemical perspective

Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10’s of km), <2.6 Myr after CAI formation. Subsequently, the Ryugu progenitor planetesimal was fragmented and evolved into the current asteroid Ryugu through sublimation

Expressions of Purpose, Emotive Response, and Contrariness to Expectation--A Study of Japanese 'No Ni' Constructions.

Ph.D.LinguisticsUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/157218/1/7229118.pd

The 'pro'-head analysis of the Japanese internally-headed relative clause

The objective of this paper is two-fold. One is to advance the view (call it the pro-head analysis) that the so-called internally-headed relative clause (IHRC) in Japanese is a nonrestrictive relative clause whose external head position is occupied by pro functioning as an E-type pronoun. It demonstrates that this view provides a natural framework in terms of which sundry and significant phenomena associated with Japanese IHRCs can be accounted for, including their characteristic properties contrasting with the corresponding change relatives and the doubly-headed relatives. The pro-head analysis contradicts a currently popular claim propagated by a series of papers that rely on null operator movement leading to the thesis that: (i) Japanese IHRCs may exhibit a “change sub-variety” (i.e., “Change IHRC”) that is not reducible to gapless externally light-headed relatives; (ii) Japanese IHRCs are strictly island-sensitive; and (iii) they disallow definite referential semantic heads. The other objective of this paper, therefore, is to present this long overdue challenge by arguing that their claims (i) ~ (iii) are not empirically sustainable, although their claim (iii) presents some difficult issues that defy clear-cut treatment as yet

Anaphora in Japanese: Kare and Zibun

Published as Coyote Papers: Proceedings of the Arizona Conference on Japanese Linguistics: The Formal Grammar SessionsIn this paper I will present a preliminary examination of two forms that participate in anaphoric relation in Japanese, i.e., reflexive zibun 'self' and pronominal kare 'he'. As such, the objective is not so much to argue for or propose definite solutions to the problems any of them may pose, as to clarify the nature of the problems involved. Section 1 examines two properties which have been ascribed to zibun, one having to do with c- command relation as suggested by Hasegawa (1981a), and the other, the widely held subject- antecedent condition. Additionally we will also see how discourse factors affect the interpretation of zibun. Section 2 deals with kare in connection with Oshima's (1979) Disjoint Reference analysis of it, as well as to Chomsky's (1979a) Binding Theory.The Coyote Papers are made available by the Arizona Linguistics Circle at the University of Arizona and the University of Arizona Libraries. Contact [email protected] with questions about these materials

Mechanisms of productivity in word formation: Transitivity alternations in Japanese

The extensive system of Japanese transitivity alternations (TrAlt) has inspired a great number of noteworthy works. This paper, adopting the theoretical apparatus of the Strong Minimalist thesis and focusing on the “in-between voice” (i.e., between the idiosyncratic lexical and the morpho-syntactic) characteristics of the TrAlt, aims to explicate its productivity phenomena. The paper offers detailed and novel analyses of transitivity suffixes -'ar' (a lexical passive) and -'e' (which has sometimes been characterized as a “causative-passive” suffix), and delineates the mechanisms of productivity by closely examining the interactive functions of these two suffixes and the verbal roots (R’s) that host them