Exploring metameric variation in human molars: A morphological study using morphometric mapping

Human molars exhibit a type of metameric variation, which is the difference in serially repeated morphology within an organism. Various theories have been proposed to explain how this variation is brought about in the molars. Actualistic data that support the theories, however, are still relatively scarce because of methodological limitations. Here we propose new methods to analyse detailed tooth crown morphologies. We applied morphometric mapping to the enamel-dentine junction of human maxillary molars and examined whether odontogenetic models were adaptable to human maxillary molars. Our results showed that the upper first molar is phenotypically distinct among the maxillary molars. The average shape of the upper first molar is characterized by four well-defined cusps and precipitous surface relief of the occlusal table. On the other hand, upper third molar is characterized by smooth surface relief of the occlusal table and shows greater shape variation and distinct distribution patterns in morphospace. The upper second molar represents an intermediate state between first and third molar. Size-related shape variation was investigated by the allometric vector analysis, and it appeared that human maxillary molars tend to converge toward the shape of the upper first molar as the size increases. Differences between the upper first molar and the upper second and third molar can thus be largely explained as an effect of allometry. Collectively, these results indicate that the observed pattern of metameric variation in human molars is consistent with odontogenetic models of molar row structure (inhibitory cascade model) and molar crown morphology (patterning cascade model). This study shows that morphometric mapping is a useful tool to visualize and quantify the morphological features of teeth, which can provide the basis for a better understanding of tooth evolution linking morphology and development

Hairball-Like Migration of “Onyx Threads” into the Draining Vein during Transarterial Embolization of a Dural Arteriovenous Fistula: A Case Report and Experimental Validation

Transarterial embolization using Onyx is a well-established treatment for dural arteriovenous fistulas (DAVFs). However, complications can arise when Onyx migrates into the venous side, impairing the draining veins. We encountered a case where Onyx, injected through the arterial side, strayed into the jugular vein, forming a hairball-like structure. Our study aimed to investigate the underlying mechanism of this unusual phenomenon. We postulated that Onyx precipitates into thread-like shapes when passing through extremely narrow openings. To test this, we extruded Onyx from a syringe through a 27-gauge needle into a silicone tube with flowing water. By varying the flow speed, we observed the hardening behavior of Onyx. Under slow flow, the extruded Onyx quickly solidified at the needle tip, forming a round mass. Conversely, high-speed flow resulted in Onyx being dispersed as small pieces. We successfully replicated the formation of “Onyx threads” under continuous slow flow conditions, similar to our case. This phenomenon occurs when Onyx unexpectedly migrates to the draining vein through a tiny opening during transarterial embolization for arteriovenous shunt diseases. Early recognition and appropriate measures are necessary to prevent occlusive complications in the draining veins and the pulmonary system

The value of big data analytics pillars in telecommunication industry

In the Big Data age, businesses in every industry must deal with vast volumes of data. Several experts and practitioners have lately emphasized the need of understanding how, why, and when Big Data Analytics (BDA) applications may be a valuable resource for businesses seeking a competitive edge. However, BDA pays off for some firms while failing to pay off for others due to the fact that investment in Big Data continues to present significant challenges due to the missing link between analytics capabilities and firm performance. According to a recent survey, many businesses spend the bulk of their time analyzing data, with only a tiny fraction employing Big Data Analytics to forecast outcomes and even fewer utilizing analytics apps to enhance processes and strategies. As a result, BDA is not widely used, and only a few companies have seen any benefit from it. To address this issue in the telecommunications domain and in light of the paucity of research on the subject, this study focused on the BDA Pillars (BDAP) in order to achieve benefits through increased revenues and cost savings. For the purpose of this research we have adopted qualitative approach with case study method, and technique of data collection includes semi-structure interview and document analysis. The Delphi technique and in-depth interviews conducted confirmed the existence of five critical elements that contribute to the sustainability of BDAPs and their impact on firm performance

Observation of gigantic spin conversion anisotropy in bismuth

Whilst the g-factor can be anisotropic due to the spin-orbit interaction (SOI), its existence in solids cannot be simply asserted from a band structure, which hinders progress on studies from such the viewpoints. The g-factor in bismuth (Bi) is largely anisotropic; especially for holes at T-point, the g-factor perpendicular to the trigonal axis is negligibly small (< 0.112), whereas the g-factor along the trigonal axis is very large (62.7). We clarified in this work that the large g- factor anisotropy gives rise to the gigantic spin conversion anisotropy in Bi from experimental and theoretical approaches. Spin-torque ferromagnetic resonance was applied to estimate the spin conversion efficiency in rhombohedral (110) Bi to be 17%, which is unlike the negligibly small efficiency in Bi(111). Harmonic Hall measurements supports the large spin conversion efficiency in Bi(110). This is the first observation of gigantic spin conversion anisotropy as the clear manifestation of the g-factor anisotropy. Beyond the emblematic case of Bi, our study unveiled the significance of the g-factor anisotropy in condensed-matter physics and can pave a pathway toward establishing novel spin physics under g-factor control.Comment: 28 pages, 7 figure

Response of a core coherent density oscillation on electron cyclotron resonance heating in Heliotron J plasma

We report properties of a coherent density oscillation observed in the core region and its response to electron cyclotron resonance heating (ECH) in Heliotron J plasma. The measurement was performed using a multi-channel beam emission spectroscopy system. The density oscillation is observed in a radial region between the core and the half radius. The poloidal mode number is found to be 1 (or 2). By modulating the ECH power with 100 Hz, repetition of formation and deformation of a strong electron temperature gradient, which is likely ascribed to be an electron internal transport barrier, is realized. Amplitude and rotation frequency of the coherent density oscillation sitting at the strong electron temperature gradient location are modulated by the ECH, while the poloidal mode structure remains almost unchanged. The change in the rotation velocity in the laboratory frame is derived. Assuming that the change of the rotation velocity is given by the background E × B velocity, a possible time evolution of the radial electric field was deduced

Current Performance and On-Going Improvements of the 8.2 m Subaru Telescope

An overview of the current status of the 8.2 m Subaru Telescope constructed and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of Japan is presented. The basic design concept and the verified performance of the telescope system are described. Also given are the status of the instrument package offered to the astronomical community, the status of operation, and some of the future plans. The status of the telescope reported in a number of SPIE papers as of the summer of 2002 are incorporated with some updates included as of 2004 February. However, readers are encouraged to check the most updated status of the telescope through the home page, http://subarutelescope.org/index.html, and/or the direct contact with the observatory staff.Comment: 18 pages (17 pages in published version), 29 figures (GIF format), This is the version before the galley proo

エナメル質の横紋形成メカニズムの解明

エナメル質の基本構造をなすエナメル小柱には横紋が観察される.この横紋は概日リズムを刻んだ成長線のひとつとして知られているが,形成メカニズムについては様々な説がある.非脱灰凍結切片で基質形成期のエナメル基質を抗アメロゲニン抗体で免疫染色すると横紋様パターンを示した.この結果から,横紋は基質形成期のアメロゲニンのタンパク量に依存した石灰化パターンであり,アメロゲニンの発現は概日的に変動するのではないかと推測した.そこで,アメロゲニンの発現に周期があるか観察するために,アメロゲニンプロモーターの下流にルシフェラーゼを繋いだコンストラクト(pGL3-1730-luc)をラットエナメル芽細胞株HAT7に遺伝子導入してアメロゲニンの転写活性を計測したところ,一定の周期をもって変動することが認められた.次に,プロモーター領域のDeletion-mutant (pGL3-464, -74, -48-luc)を作製して周期性の制御に関わる領域を検索した結果, C/EBPαのbindingモチーフが有力な候補と考えられた.その転写はMsx2によって制御を受けることが知られていることから, Msx2の発現ベクターを用いた強制発現の影響を調べたところ,そのリズムが消失した.またMsx2の遺伝子欠損マウスには基質形成の横紋様パターンが見られなかった.以上の結果から, Msx2がアメロゲニンの発現周期に影響していることが推測され,さらにアメロゲニンの発現量の周期的変化によって生じた基質形成パターンが,横紋形成に関与していると考えられた.In enamel rods, periodic bands referred to as \u27cross-striations\u27 are observed, and known as incremental lines of circadian rhythm. Though it is considered that the cross-striation is involved in the biological circadian rhythm during the secretion of enamel matrix protein by ameloblasts, the developmental mechanism involved has not been examined in detail. By immunostaining amelogenin in fresh frozen sections of mouse lower incisor, we could observe fluorescent periodic bands in the enamel matrix, which were identical to the pattern of these cross-striations. Accordingly, we focused on the biological rhythm in the section of amelogenin. We examined amelogenin mRNA transcriptional activity in an ameloblast cell line (HAT7) by using real-time luminescence microscopy. The results showed that amelogenin mRNA transcriptional activity exhibited periodic rhythmicity and that Msx2 over-expression led to the disappearance of the periodic change. Further, in the lower incisors of Msx2-deficient mice, the periodic bands were not observed. Taken together, our findings suggest that the formation of cross-striations in the enamel rods was associated with the expression of amelogenin regulated by the transcriptional activity