501 research outputs found

    Oxygen and light element synthesis by neutron-capture reactions in metal-free and extremely metal-poor AGB stars

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    The metal-free (Pop. III) and extremely metal-poor (EMP) stars of low- and intermediate-masses experience mixing of hydrogen into the helium convection during the early TP-AGB phase, differently from the meal-rich stars. We study the nucleosynthesis in the helium convective zone with 13C formed from mixed protons as neutron source by using a nuclear network from H through S. In the absence or scarcity of the pristine metals, the neutron-recycling reactions, 12C(n,g)13C(a,n)16O and also 16O(n,g)17O(a,n)20Ne promote the synthesis of O and light elements, including their neutron-rich isotopes and the odd atomic number elements. Based on the results, we demonstrate that the peculiar abundance patterns of C through Al observed for the three most iron-deficient, carbon-rich stars can be reproduced in terms of the nucleosynthesis in Pop. III, AGB stars in the different mass range. We argue that these three stars were born as the low-mass members of Pop. III binaries and later subject to the surface pollution by the mass transfer in the binary systems. It is also shown that the AGB nucleosynthesis with hydrogen mixing explains the abundances of C, O, Na, Mg and Al observed for most of carbon-enhanced EMP (CEMP) stars, including all CEMP-s stars with s-process elements. In addition the present results are used to single out other nucleosynthetic signatures of early generations of stars.Comment: 46 pages, 13 figures, accepted for PAS

    Distributed Quantum Interactive Proofs

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    The study of distributed interactive proofs was initiated by Kol, Oshman, and Saxena [PODC 2018] as a generalization of distributed decision mechanisms (proof-labeling schemes, etc.), and has received a lot of attention in recent years. In distributed interactive proofs, the nodes of an n-node network G can exchange short messages (called certificates) with a powerful prover. The goal is to decide if the input (including G itself) belongs to some language, with as few turns of interaction and as few bits exchanged between nodes and the prover as possible. There are several results showing that the size of certificates can be reduced drastically with a constant number of interactions compared to non-interactive distributed proofs. In this paper, we introduce the quantum counterpart of distributed interactive proofs: certificates can now be quantum bits, and the nodes of the network can perform quantum computation. The first result of this paper shows that by using distributed quantum interactive proofs, the number of interactions can be significantly reduced. More precisely, our result shows that for any constant k, the class of languages that can be decided by a k-turn classical (i.e., non-quantum) distributed interactive protocol with f(n)-bit certificate size is contained in the class of languages that can be decided by a 5-turn distributed quantum interactive protocol with O(f(n))-bit certificate size. We also show that if we allow to use shared randomness, the number of turns can be reduced to three. Since no similar turn-reduction classical technique is currently known, our result gives evidence of the power of quantum computation in the setting of distributed interactive proofs as well. As a corollary of our results, we show that there exist 5-turn/3-turn distributed quantum interactive protocols with small certificate size for problems that have been considered in prior works on distributed interactive proofs such as [Kol, Oshman, and Saxena PODC 2018, Naor, Parter, and Yogev SODA 2020]. We then utilize the framework of the distributed quantum interactive proofs to test closeness of two quantum states each of which is distributed over the entire network

    Brief Announcement: Distributed Quantum Interactive Proofs

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    The study of distributed interactive proofs was initiated by Kol, Oshman, and Saxena [PODC 2018] as a generalization of distributed decision mechanisms (proof-labeling schemes, etc.), and has received a lot of attention in recent years. In distributed interactive proofs, the nodes of an n-node network G can exchange short messages (called certificates) with a powerful prover. The goal is to decide if the input (including G itself) belongs to some language, with as few turns of interaction and as few bits exchanged between nodes and the prover as possible. There are several results showing that the size of certificates can be reduced drastically with a constant number of interactions compared to non-interactive distributed proofs. In this brief announcement, we introduce the quantum counterpart of distributed interactive proofs: certificates can now be quantum bits, and the nodes of the network can perform quantum computation. The main result of this paper shows that by using quantum distributed interactive proofs, the number of interactions can be significantly reduced. More precisely, our main result shows that for any constant k, the class of languages that can be decided by a k-turn classical (i.e., non-quantum) distributed interactive protocol with f(n)-bit certificate size is contained in the class of languages that can be decided by a 5-turn distributed quantum interactive protocol with O(f(n))-bit certificate size. We also show that if we allow to use shared randomness, the number of turns can be reduced to 3-turn. Since no similar turn-reduction classical technique is currently known, our result gives evidence of the power of quantum computation in the setting of distributed interactive proofs as well

    Autotransplantation of Hepatic Granulomas into the Skin of Mice with Schistosoma mansoni Infection

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    Hepatic egg granulomas of mice infected with Schistosoma mansoni were transplanted into the skin of the same animal and changes occurring to macrophages, eosinophils, and mast cells over time were studied by light and electron microscopy and by autoradiographic techniques. Disappearance of cellular components about the egg granulomas occurred within 1week; the entire implant became encapsulated by inflammatory cells and stroma. By 3weeks monomuclear cells and macrophages reorganized the granulomas around the eggs and neutrophils disappeared. Activated macrophages contained both secretory rough endoplasmic reticulum and lysosomal-dense bodies. Granuloma size increased up to 5weeks after implantation and mast cells and cosinophils tended to migrate into the granulomas. The mast cell index always remained lower than in the original hepatic granulomas, while eosinophils were seen in large numbers. During 3 to 8weeks after implantation mononuclear cells undergoing DNA synthesis in the granulomas ranged from 2.9–4.8%. Some 3-week-old autotransplants were injected with 3H-thymidine and biopsied from 1 to 21days later. Labeled mononuclear cells peaked in the granulomas by 10days (24%) and the numbers fell off sharply after that.These findings indicate that autologously implanted schistosome egg granulomas can be maintained successfully in the skin for prolonged periods with marked ingress of macrophages and eosinophils. The autoradiographic data suggest lesions are high turnover granulomas

    Distributed Merlin-Arthur Synthesis of Quantum States and Its Applications

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    The generation and verification of quantum states are fundamental tasks for quantum information processing that have recently been investigated by Irani, Natarajan, Nirkhe, Rao and Yuen [CCC 2022] and Rosenthal and Yuen [ITCS 2022] under the term \emph{state synthesis}. This paper studies this concept from the viewpoint of quantum distributed computing, and especially distributed quantum Merlin-Arthur (dQMA) protocols. We first introduce a novel task, on a line, called state generation with distributed inputs (SGDI). In this task, the goal is to generate the quantum state UψU\ket{\psi} at the rightmost node of the line, where ψ\ket{\psi} is a quantum state given at the leftmost node and UU is a unitary matrix whose description is distributed over the nodes of the line. We give a dQMA protocol for SGDI and utilize this protocol to construct a dQMA protocol for the Set Equality problem studied by Naor, Parter and Yogev [SODA 2020]. Our second contribution is a technique, based on a recent work by Zhu and Hayashi [Physical Review A, 2019], to create EPR-pairs between adjacent nodes of a network without quantum communication. As an application of this technique, we prove a general result showing how to convert any dQMA protocol on an arbitrary network into another dQMA protocol where the verification stage does not require any quantum communication.Comment: 20 page

    Distributed Quantum Interactive Proofs

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    The study of distributed interactive proofs was initiated by Kol, Oshman, and Saxena [PODC 2018] as a generalization of distributed decision mechanisms (proof-labeling schemes, etc.), and has received a lot of attention in recent years. In distributed interactive proofs, the nodes of an nn-node network GG can exchange short messages (called certificates) with a powerful prover. The goal is to decide if the input (including GG itself) belongs to some language, with as few turns of interaction and as few bits exchanged between nodes and the prover as possible. There are several results showing that the size of certificates can be reduced drastically with a constant number of interactions compared to non-interactive distributed proofs. In this paper, we introduce the quantum counterpart of distributed interactive proofs: certificates can now be quantum bits, and the nodes of the network can perform quantum computation. The first result of this paper shows that by using quantum distributed interactive proofs, the number of interactions can be significantly reduced. More precisely, our result shows that for any constant~kk, the class of languages that can be decided by a kk-turn classical (i.e., non-quantum) distributed interactive protocol with f(n)f(n)-bit certificate size is contained in the class of languages that can be decided by a 55-turn distributed quantum interactive protocol with O(f(n))O(f(n))-bit certificate size. We also show that if we allow to use shared randomness, the number of turns can be reduced to 3-turn. Since no similar turn-reduction \emph{classical} technique is currently known, our result gives evidence of the power of quantum computation in the setting of distributed interactive proofs as well.Comment: 25 page

    イオンクロマトグラフィーの高機能化の開発に関する基礎的研究

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    取得学位:博士(学術),学位授与番号:博乙第116号,学位授与年月日:平成8年3月25日,学位授与年:199

    Liver Sarcoidosis with Unique MRI Images Using Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid

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    Sarcoidosis is a systemic disease characterized by the formation of non-caseating granulomas in multiple organs. In the diagnosis of sarcoidosis, imaging modalities such as ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) are useful;however, there are few reports of MRI imaging using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB) MRI. A 46-year-old Japanese female with suspected pulmonary sarcoidosis was admitted to our hospital because low-density mottles in the liver were observed incidentally by chest CT. The low-density mottles were not enhanced at the arterial phase or portal phase by abdominal CT and MRI, and decreased uptake was observed in the hepatobiliary phase of Gd-EOB MRI. No hematological disorder was observed except for a slight increase of biliary enzymes. The lesion was diagnosed as liver sarcoidosis by the liver biopsy. Since the patient refused steroid therapy, we prescribed ursodeoxycholic acid (UDCA). 600mg/day. The serum levels of biliary enzymes were normalized and the abdominal CT findings gradually improved after the initiation of UDCA medication. Gd-EOB MRI showed unique hypointense areas in the liver at the hepatobiliary phase, which might be useful in the diagnosis of liver sarcoidosis
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