1
|
Kubo R, Asanuma Y, Fujimoto E, Okuyama H, Ono M, Takahashi JI. Cross-mating between the alien bumblebee Bombus terrestris and two native Japanese bumblebees, B. hypocrita sapporensis and B. cryptarum florilegus, in the Nemuro Peninsula, Japan. Sci Rep 2023; 13:11506. [PMID: 37460583 PMCID: PMC10352366 DOI: 10.1038/s41598-023-38631-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 07/12/2023] [Indexed: 07/20/2023] Open
Abstract
The rapid naturalization of Bombus terrestris across the Nemuro Peninsula has led to a decline in two closely related native Japanese species, namely Bombus hypocrita sapporensis and Bombus cryptarum florilegus, both belonging to the common subgenus Bombus. Although it is widely believed that cross-mating of native and non-native species is influenced by the common male sex pheromone in this region, no study has been conducted to substantiate this claim. Thus, we investigated the cross-activities of male sex pheromones between native and non-native bumblebees, as well as the frequencies of cross-mating, using chemical and DNA assays. Our gas chromatography-electroantennographic detector analyses and behavioral tests revealed the presence of sex pheromonal cross-activities between B. terrestris and the two Japanese bumblebees species. Furthermore, DNA analyses revealed the occurrence of cross-mating between native and non-native species in the Nemuro Peninsula. Overall, these results indicate the immediate need for conservation measures to safeguard Japanese bumblebee populations in the Nemuro Peninsula.
Collapse
Affiliation(s)
- Ryohei Kubo
- Honeybee Science Research Center, Tamagawa University, 6-1-1, Tamagawagakuen, Machida, Tokyo, Japan
| | - Yuine Asanuma
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-Ku, Kyoto, Japan
| | - Erina Fujimoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-Ku, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-Ku, Kyoto, Japan
| | - Masato Ono
- Honeybee Science Research Center, Tamagawa University, 6-1-1, Tamagawagakuen, Machida, Tokyo, Japan
| | - Jun-Ichi Takahashi
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-Ku, Kyoto, Japan.
| |
Collapse
|
2
|
Kobayashi K, Ise JI, Aoki R, Kinoshita M, Naito K, Udo T, Kunwar B, Takahashi JI, Shibata H, Mita H, Fukuda H, Oguri Y, Kawamura K, Kebukawa Y, Airapetian VS. Formation of Amino Acids and Carboxylic Acids in Weakly Reducing Planetary Atmospheres by Solar Energetic Particles from the Young Sun. Life (Basel) 2023; 13:life13051103. [PMID: 37240748 DOI: 10.3390/life13051103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 05/28/2023] Open
Abstract
Life most likely started during the Hadean Eon; however, the environmental conditions which contributed to the complexity of its chemistry are poorly known. A better understanding of various environmental conditions, including global (heliospheric) and local (atmospheric, surface, and oceanic), along with the internal dynamic conditions of the early Earth, are required to understand the onset of abiogenesis. Herein, we examine the contributions of galactic cosmic rays (GCRs) and solar energetic particles (SEPs) associated with superflares from the young Sun to the formation of amino acids and carboxylic acids in weakly reduced gas mixtures representing the early Earth's atmosphere. We also compare the products with those introduced by lightning events and solar ultraviolet light (UV). In a series of laboratory experiments, we detected and characterized the formation of amino acids and carboxylic acids via proton irradiation of a mixture of carbon dioxide, methane, nitrogen, and water in various mixing ratios. These experiments show the detection of amino acids after acid hydrolysis when 0.5% (v/v) of initial methane was introduced to the gas mixture. In the set of experiments with spark discharges (simulation of lightning flashes) performed for the same gas mixture, we found that at least 15% methane was required to detect the formation of amino acids, and no amino acids were detected in experiments via UV irradiation, even when 50% methane was used. Carboxylic acids were formed in non-reducing gas mixtures (0% methane) by proton irradiation and spark discharges. Hence, we suggest that GCRs and SEP events from the young Sun represent the most effective energy sources for the prebiotic formation of biologically important organic compounds from weakly reducing atmospheres. Since the energy flux of space weather, which generated frequent SEPs from the young Sun in the first 600 million years after the birth of the solar system, was expected to be much greater than that of GCRs, we conclude that SEP-driven energetic protons are the most promising energy sources for the prebiotic production of bioorganic compounds in the atmosphere of the Hadean Earth.
Collapse
Affiliation(s)
- Kensei Kobayashi
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Jun-Ichi Ise
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Ryohei Aoki
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Miei Kinoshita
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Koki Naito
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Takumi Udo
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Bhagawati Kunwar
- Chubu Institute of Advanced Studies, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501, Japan
| | - Jun-Ichi Takahashi
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Hiromi Shibata
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Ibaraki 567-0047, Japan
| | - Hajime Mita
- Department of Life, Environment and Applied Chemistry, Faculty of Engineering, Fukuoka Institute of Technology, Fukuoka 811-0295, Japan
| | - Hitoshi Fukuda
- Open Facility Center, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Yoshiyuki Oguri
- Institute of Innovative Research, Tokyo Institute of Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Kimitaka Kawamura
- Chubu Institute of Advanced Studies, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501, Japan
| | - Yoko Kebukawa
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Vladimir S Airapetian
- NASA Goddard Space Flight Center/Sellers Exoplanetary Environments Collaboration, Greenbelt, MD 20771, USA
- Department of Physics, American University, Washington, DC 20016, USA
- Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
3
|
Kishimoto Y, Okuyama H, Takahashi JI. Complete mitochondrial DNA sequence of the Japanese endemic catfish Silurus biwaensis (Siluriformes: Siluridae) from Lake Biwa. Mitochondrial DNA B Resour 2021; 6:2482-2483. [PMID: 34395882 PMCID: PMC8354177 DOI: 10.1080/23802359.2021.1920487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The Japanese endemic catfish Silurus biwaensis is distributed only in Lake Biwa and Yodo river drainages. There are four species of the genus Silurus in Japan, of which S. biwaensis has a most limited distribution. This catfish needs to be collected for DNA data owing to the lack of information related to its phylogenetic relationship. Here, the complete mitochondrial genome of the S. biwaensis from Lake Biwa in Japan was analyzed using next-generation sequencing. The mitochondrial genome of S. biwaensis was identified as a 16,531 bp circular molecule containing 13 protein-coding genes (PCGs), 22 tRNA genes, and 2 rRNA genes, along with one A + T-rich control region. The AT content was 55.83%. The heavy (H)-strand was predicted to have 12 PCGs, 14 tRNA, and 2 rRNA genes, whereas the light (L)-strand was predicted to contain one PCG and eight tRNA genes. The start codons ATG, ATC, and GTG were found in 13 PCGs. The stop codons TAA, TAG, and AGA were observed in all PCGs, except CytB and COX3. All tRNA genes formed typical cloverleaf secondary structures. The molecular phylogenetic relationships estimated using 13 PCGs (maximum-likelihood method) indicated that S. biwaensis is genetically distinct from the sympatric species S. asotus and S. lithophilus. This result clearly indicated that S. biwaensis is a valid species.
Collapse
Affiliation(s)
- Yuu Kishimoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | | |
Collapse
|
4
|
Kishimoto Y, Okuyama H, Takahashi JI. Complete mitochondrial DNA sequence of the Japanese endemic catfish Silurus lithophilus (Siluriformes: Siluridae). Mitochondrial DNA B Resour 2021; 6:2559-2561. [PMID: 34377829 PMCID: PMC8344260 DOI: 10.1080/23802359.2021.1920486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Japanese endemic catfish Silurus lithophilus is distributed only in Lake Biwa, Lake Yogo, and their river drainages. There are four species of the genus Silurus in Japan, of which S. lithophilus has a limited distribution. This catfish needs to be collected for DNA data owing to the lack of information related to its conservation. Here, the complete mitochondrial genome of the S. lithophilus from Lake Biwa in Japan was analyzed using next-generation sequencing. The mitochondrial genome of S. lithophilus was identified as a 16,524 bp circular molecule containing 13 protein-coding genes (PCGs), 22 tRNA genes, and 2 rRNA genes, along with one A + T-rich control region. The AT content was 55.89%. The heavy (H)-strand was predicted to have 12 PCGs and 15 tRNA, and 2 rRNA genes, whereas the light (L)-strand was predicted to contain one PCG and seven tRNA genes. The start codons ATG and GTG were found in 13 PCGs. The stop codons TAA, TAG, and AGA were observed in all PCGs, except CytB. All tRNA genes formed typical cloverleaf secondary structures. The molecular phylogenetic relationship, inferred using 13 PCGs (based on the maximum likelihood), was consistent with that reported in previous studies, which predicted a sister relationship between S. lithophilus and S. asotus. The results also clearly indicated that S. lithophilus is a valid species.
Collapse
Affiliation(s)
- Yuu Kishimoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | | |
Collapse
|
5
|
Nakasako J, Okuyama H, Ohba S, Takahashi JI. Complete mitochondrial DNA sequence of the giant water bug Kirkaldyia deyrolli (Hemiptera: Belostomatidae). Mitochondrial DNA B Resour 2020; 5:3739-3740. [PMID: 33367081 PMCID: PMC7671606 DOI: 10.1080/23802359.2020.1833774] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Giant water bugs (genus Kirkaldyia and Lethocerus) are well known species from aquatic habitats throughout the world’s subtropical and tropical areas. Only one species of the Kirkaldyia deyrolli is distributed in Japan. K. deyrolli has been designated as second category rare species according Law for Conservation of Endangered Species of Wild Fauna and Flora in Japan, in 2019. We analyzed, for the first time, the complete mitochondrial genomes of the giant water bug K. deyrolli from Japan using next-generation sequencing. The mitochondrial genome was a circular and 15,579 bp molecule that included 13 protein-coding genes (PCGs), 22 tRNA genes, and two ribosomal RNA genes, along with one AT-rich control region. The AT content value was 69.55%. The heavy strand was predicted to have nine PCGs and 15 tRNA genes, whereas the light strand was predicted to contain four PCGs, seven tRNA genes, and two rRNA genes. Start codons were variable for all PCGs: four ATA, three ATC, four ATG, two ATT genes as the start codon. Stop codons were of two types: TAA for 12 genes and TAG for one gene. Incomplete stop codon T was identified. The molecular phylogenetic relationship, inferred using 13 PCGs, was consistent with that reported in previous studies, which predicted a sister relationship to the genus Lethocerus.
Collapse
Affiliation(s)
- Juiki Nakasako
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Shinya Ohba
- Biological Laboratory, Faculty of Education, Nagasaki University, Nagasaki, Japan
| | | |
Collapse
|
6
|
Taniwaki T, Hiroshima M, Imakita M, Kishimoto Y, Okuyama H, Takahashi JI. Complete mitochondrial DNA sequence of the East Asian minnow, Pungtungia herzi (Actinopterygii: Cypriniformes). Mitochondrial DNA B Resour 2020; 5:3127-3129. [PMID: 33458083 PMCID: PMC7782132 DOI: 10.1080/23802359.2020.1800423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Some populations of the East Asian minnow Pungtungia herzi Herzenstein, 1892, which are naturally distributed in western Japan, have declined and are considered endangered. However, P. herzi has become a domestic invasive species in eastern Japan. Thus, knowledge of genetic features and phylogenetic relationships of P. herzi is important for conservation of this species and understanding its impact on ecosystems. We analyzed the complete mitochondrial genome using next generation sequencing of the East Asian minnow P. herzi from Yodo River, Osaka Prefecture, Japan. The mitochondrial genome of P. herzi consists of a circular molecule of 16,599 bp that includes 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one control region. The heavy (H)-strand was predicted to have 12 PCGs, 14 tRNA, and two rRNA genes, while the light (L)-strand was predicted to contain one PCGs and eight tRNA genes. The average AT content was 57.68%. The genes ATP8 and ATP6, ATP6 and COIII, ND4L and ND4, and ND5 and ND6 shared seven, one, seven, and four nucleotides, respectively. The initiation codons ATG and GTG were found in 12 and one genes, respectively. The termination codons TAA, TAG, incomplete TA–, and single T–– were observed in nine, one, one, and two genes, respectively. All the tRNA genes possessed a cloverleaf secondary structure. The phylogenetic relationships inferred using 13 PCGs (based on the maximum likelihood) were consistent with previous studies that predicted interrelationships of Cypriniformes.
Collapse
Affiliation(s)
- Teppei Taniwaki
- Osaka High School, Osaka, Japan.,Osaka High School Science Research Club, Osaka, Japan
| | | | | | - Yuu Kishimoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Jun-Ichi Takahashi
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| |
Collapse
|
7
|
Harada R, Yoshioka M, Okuyama H, Kato M, Martin SJ, Takahashi JI. Complete mitochondrial DNA sequence of the parasitic honey bee mite Varroa destructor (Mesostigmata: Varroidae). Mitochondrial DNA B Resour 2020; 5:635-636. [PMID: 33366680 PMCID: PMC7748463 DOI: 10.1080/23802359.2019.1711219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Varroa destructor is a parasite mite of the eastern honey bee Apis cerana, which is native to Asia. The European honey bee Apis mellifera was imported to Asia from Europe and the USA for apiculture in the 19th century. In a short period of time, V. destructor parasitized the artificially introduced honey bees. Varroa destructor was estimated to have spread around the world with A. mellifera when it was exported from Asia to locations worldwide about 50 years ago. The mitochondrial DNA of the parasitic honey bee mite V. destructor was analyzed using next-generation sequencing. The complete mitochondrial genome of V. destructor was identified as a 16,476-bp circular molecule containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one AT-rich control region. The heavy strand was predicted to have nine PCGs and 13 tRNA genes, whereas the light strand was predicted to contain four PCGs, nine tRNA genes, and two rRNA genes. All PCGs began with ATA as the start codon, except COIII and CytB, which had ATG as the start codon. Stop codons were of two types: TAA for eight genes and TAG for five genes. Molecular phylogenetic analysis revealed that V. destructor from Japan was genetically distant from that of France. A high base substitution rate of 2.82% was also confirmed between the complete mitochondrial DNA sequences of V. destructor from Japan and the USA, suggesting that one Varroa mite strain found in the USA is not from Japan.
Collapse
Affiliation(s)
- Reona Harada
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Masato Yoshioka
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | | | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | | |
Collapse
|
8
|
Okuyama H, Kiyoshi T, Takahashi JI, Tsubaki Y. A comparison of complete mitochondrial DNA sequences of Mnais costalis Selys, 1869 (Odonata: Calopterygidae) from three different populations (one allopatric and two sympatric). Mitochondrial DNA B Resour 2019; 4:3104-3105. [PMID: 33365872 PMCID: PMC7707004 DOI: 10.1080/23802359.2019.1667888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 08/16/2019] [Indexed: 10/29/2022] Open
Abstract
In Japan, two closely-related damselflies, Mnais costalis Selys, 1869 (Odonata: Calopterygidae) and M. pruinosa Selys-Longchamps (Odonata: Calopterygidae), 1853, coexist, and they exhibit geographic variations in wing color, body size, and habitat preference. In this study, we analyzed the complete mitochondrial genome of M. costalis from Saga Prefecture, Japan (sympatric populations that exhibit wing color polymorphism), and compared the genome with M. costalis that exhibit monomorphic orange wing color. The mitochondrial genome of M. costalis from Saga Prefecture was identified as a circular molecule of 15,488 bp, similar to that found in other M. costalis populations. It was predicted to contain 13 protein-coding (PCG), 22 tRNA, and two rRNA genes, along with one A + T-rich control region. Among the PCGs, ATP8 and ATP6, ATP6 and COIII, ND4 and ND4L, and ND6 and Cytb shared seven, one, seven, and one nucleotides, respectively. The initiation codon ATG was found in eight genes, ATC in four, and ATT in one, while the termination codons TAA, TAG, TA, and T were observed in seven, one, two, and three genes, respectively. All the tRNA genes possessed a cloverleaf secondary structure, except for tRNA-His that lacks the TΨC loop. The average AT content of mitochondrial genome was 66.06%. From a phylogenetic analysis, the loss of wing color polymorphism in monomorphic sympatric populations is likely to occur with the coexistence of two Mnais species.
Collapse
Affiliation(s)
- Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Takuya Kiyoshi
- Department of Zoology, National Museum of Nature and Science, Tokyo, Japan
| | | | | |
Collapse
|
9
|
Okuyama H, Kiyoshi T, Takahashi JI, Tsubaki Y. Complete mitochondrial genome sequence of the broad-winged damselfly, Mnais pruinosa Selys, 1853 (Odonata: Calopterygidae). Mitochondrial DNA B Resour 2019; 4:3101-3103. [PMID: 33365871 PMCID: PMC7706464 DOI: 10.1080/23802359.2019.1667887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In this study, we analyzed the complete mitochondrial genome of the Mnais pruinosa Selys, 1853 from Saga Prefecture, Japan. The mitochondrial genome of M. pruinosa was identified as a circular molecule of 15,494 bp, and was found to be similar to that of other damselfly species. It was predicted to contain 13 protein-coding (PCG), 22 tRNA, and two rRNA genes, as well as one A + T-rich control region. The genes ATP8 and ATP6 shared seven nucleotides, ATP6 and COIII shared one nucleotide, ND4 and ND4L shared seven nucleotides, and ND6 and Cytb shared one nucleotide. The initiation codon ATG was found in eight genes, ATC in four, and ATT in one; the termination codons TAA, TAG, incomplete TA, and single T were observed in seven, one, two, and three genes, respectively. All the tRNA genes possessed a cloverleaf secondary structure, except for tRNA-His that lacks the TΨC loop. The average AT content of mitochondrial genome was 66.18%.
Collapse
Affiliation(s)
- Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Takuya Kiyoshi
- Department of Zoology, National Museum of Nature and Science, Tokyo, Japan
| | | | | |
Collapse
|
10
|
Yamasaki K, Takahashi R, Harada R, Matsuo Y, Nakamura M, Takahashi JI. Reproductive interference by alien hornet Vespa velutina threatens the native populations of Vespa simillima in Japan. Naturwissenschaften 2019; 106:15. [PMID: 30989338 DOI: 10.1007/s00114-019-1609-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/25/2019] [Accepted: 03/15/2019] [Indexed: 10/27/2022]
Abstract
The yellow-legged hornet Vespa velutina has become one of the major alien species in European and East Asian countries. As in its homeland, the invading V. velutina is reported as the major predator of honeybees and is becoming a threat to beekeeping in Europe. However, it remains unknown how V. velutina might affect native hornets when it invades Asia, where a large number of Vespa species are distributed. Thus, by analyzing the mitochondrial cytochrome c oxidase subunit I gene, we investigated whether interspecific mating occurs between V. velutina and Japanese native Vespa spp. Our results showed that the alien V. velutina causes reproductive interference in Japanese native hornet Vespa simillima. Forty-three percent of native V. simillima queens had the sperm of V. velutina males, and among the all V. simillima queens analyzed, 28% only had V. velutina sperm. We did not find evidence of V. velutina queens having the sperm of V. simillima males. These findings suggest that reproductive interference by V. velutina males poses a threat to the native V. simillima populations. A decline of V. simillima may also negatively affect other insects that interact with V. simillima.
Collapse
Affiliation(s)
- Kazuhisa Yamasaki
- Institute for Sustainable Agro-ecosystem Services, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Japan.,Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Ryoichi Takahashi
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Reona Harada
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Yuya Matsuo
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Masao Nakamura
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan
| | - Jun-Ichi Takahashi
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo, Motoyama, Kita-ku, Kyoto, Japan.
| |
Collapse
|
11
|
Maeda M, Nakagawa I, Chikano M, Okuyama H, Murray R, Takahashi JI. The complete mitochondrial genome of the dusky brown-gray-colored honeybee, Apis mellifera (insecta: Hymenoptera: Apidae) of New Zealand. Mitochondrial DNA B Resour 2018; 3:996-997. [PMID: 33474393 PMCID: PMC7800894 DOI: 10.1080/23802359.2018.1507641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/29/2018] [Indexed: 11/19/2022] Open
Abstract
We analyzed the complete mitochondrial genome of the dusky brown-gray-colored honeybee Apis mellifera, collected from North Island, New Zealand. We determined that the mitochondrial genome was a 16,336 bp and predicted 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. The start codon ATA was found in two genes, ATG in four genes, ATT in six genes, and ATC in one gene, whereas the termination codon TAA was observed in all PCGs. The non-coding regions of tRNA-Leu and COII were consistent with the C haplotype of A. mellifera carnica. Phylogenetic analysis suggests a close relationship with the European A. mellifera.
Collapse
Affiliation(s)
- Mito Maeda
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Ikumi Nakagawa
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Mao Chikano
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | | | | |
Collapse
|
12
|
Takahashi R, Okuyama H, Minoshima YN, Takahashi JI. Complete mitochondrial DNA sequence of the alien hornet Vespa velutina (Insecta: Hymenoptera) invading Kyushu Island, Japan. Mitochondrial DNA B Resour 2018; 3:179-181. [PMID: 33474110 PMCID: PMC7799621 DOI: 10.1080/23802359.2018.1437823] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 02/01/2018] [Indexed: 11/23/2022] Open
Abstract
We analyzed the complete mitochondrial genome of the invasive Asian hornet Vespa velutina from Kyushu Island, Japan. The mitochondrial genome of V. velutina was identified as a circular molecule of 16,388 bp. We predicted that the genome contains 13 protein-coding genes (PCGs), 22 tRNA genes, and 2 rRNA genes, along with one A + T-rich control region. The average AT content is 81.68%. Molecular phylogenetic analysis using the 13 mitochondrial PCGs from 11 closely related taxa of Vespidae indicated that the V. velutina invading the Japanese Islands of Kyushu and Tsushima have a common origin.
Collapse
Affiliation(s)
| | - Hisashi Okuyama
- Faculty of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | | | | |
Collapse
|
13
|
Nakagawa I, Maeda M, Chikano M, Okuyama H, Murray R, Takahashi JI. The complete mitochondrial genome of the yellow coloured honeybee Apis mellifera (Insecta: Hymenoptera: Apidae) of New Zealand. Mitochondrial DNA B Resour 2018; 3:66-67. [PMID: 33474068 PMCID: PMC7800568 DOI: 10.1080/23802359.2017.1422401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 12/26/2017] [Indexed: 12/02/2022] Open
Abstract
The complete mitochondrial genome of the yellow coloured honeybee Apis mellifera from North Island, New Zealand was analyzed using next-generation sequencing. The mitochondrial genome was a 16,349bp circular molecule and was predicted to contain 13 protein-coding genes (PCGs), 22 tRNA genes and two rRNA genes. The initiation codon ATA was found in two genes, ATG in four genes, ATT in six genes, and ATC in one gene, while the termination codon TAA was observed in all the PCGs. Phylogenetic analysis using the sequence of 23 closely related taxa suggested a sister relationship with the Italian strain A. mellifera ligustica.
Collapse
Affiliation(s)
- Ikumi Nakagawa
- Faculty of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Mito Maeda
- Faculty of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Mao Chikano
- Faculty of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | | | | |
Collapse
|
14
|
Okuyama H, Martin SJ, Takahashi JI. Complete mitochondrial DNA sequence of the tropical hornet Vespa affinis (Insecta, Hymenoptera). Mitochondrial DNA B Resour 2017; 2:776-777. [PMID: 33473977 PMCID: PMC7800416 DOI: 10.1080/23802359.2017.1398622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 10/26/2017] [Indexed: 11/07/2022] Open
Abstract
We analyzed the complete mitochondrial genome of the Asian tropical hornet Vespa affinis from Ishigaki Island, Japan. It consisted of a circular molecule with 19,109 bp, which is larger to other hornet species e.g. V. velutina. We predicted the genome contained 13 protein-coding, 22 tRNA, and two rRNA genes, along with one A + T-rich control region. The repetitive sequences were confirmed at multiple positions in the non-coding genes. The initiation codons ATA was found in one, ATG in seven, and ATT in five genes, while the termination codons TAA and TAG were observed 11 and two genes, respectively. The average AT content of the genome was 78.4%.
Collapse
Affiliation(s)
- Hisashi Okuyama
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Stephen J. Martin
- School of Environment & Life Sciences, University of Salford, Manchester, UK
| | | |
Collapse
|
15
|
Takahashi JI, Tingek S, Okuyama H. The complete mitochondrial DNA sequence of endemic honeybee Apis nuluensis (Insecta: Hymenoptera: Apidae) inhabiting Mount Kinabalu in Sabah Province, Borneo Island. Mitochondrial DNA B Resour 2017; 2:585-586. [PMID: 33473910 PMCID: PMC7799508 DOI: 10.1080/23802359.2017.1372714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 08/24/2017] [Indexed: 11/18/2022] Open
Abstract
The cavity-nesting honeybee Apis nuluensis inhabits only the highlands of Mount Kinabalu of Sabah, Borneo Island. The mitochondrial genome is a circular molecule of approximately 1.6 kb that includes 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one AT-rich control region. The average AT content was 84.5%. The start codons ATC, ATG, and ATT were found in one, three, and nine genes, respectively, whereas the stop codon TAA was observed in all genes. The phylogenetic relationship, inferred using 13 PCGs, was consistent with that reported in previous studies that predicted a sister taxon relationship between A. nuluensis and A. cerana.
Collapse
Affiliation(s)
| | | | - Hisashi Okuyama
- Department of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| |
Collapse
|
16
|
Takahashi R, Okuyama H, Kiyoshi T, Takahashi JI. Complete mitochondrial DNA sequence of the invasive hornet Vespa velutina (Insecta, Hymenoptera) found in Japan. Mitochondrial DNA B Resour 2017; 2:143-144. [PMID: 33473746 PMCID: PMC7799611 DOI: 10.1080/23802359.2017.1289353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
In this study, we analyzed the complete mitochondrial genome of the invasive Asian hornet Vespa velutina from Japan. The mitochondrial genome of V. velutina was identified as a circular molecule of 16,765 bp, similar to that in other hornet species. It was predicted to contain 13 protein-coding, 20 tRNA, and two rRNA genes, along with one A + T-rich control region. The initiation codons ATC was found in one, ATG in four, ATT in five, and ATA in three genes, while TAA was the termination codon in all these genes. The average AT content of 13 protein-coding was 82%.
Collapse
Affiliation(s)
| | - Hisashi Okuyama
- Department of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Takuya Kiyoshi
- Department of Zoology, National Museum of Nature and Science, Tokyo, Japan
| | | |
Collapse
|
17
|
Inoue S, Seyama M, Miura T, Horiuchi T, Iwasaki Y, Takahashi JI, Hayashi K, Tamechika E. A reliable aptamer array prepared by repeating inkjet-spotting toward on-site measurement. Biosens Bioelectron 2016; 85:943-949. [PMID: 27315520 DOI: 10.1016/j.bios.2016.05.089] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/14/2016] [Accepted: 05/30/2016] [Indexed: 10/21/2022]
Abstract
A preparation protocol is proposed for a reliable aptamer array utilizing an ink-jet spotter. We accumulated streptavidin and biotinylated-aptamer in this order on a biotinylated-polyethylene glycol-coated gold substrate to prepare an aptamer array. The aptamer array was prepared with an alternate spotting structure where each aptamer spot was placed between reference spots formed with blocking solution thus suppressing contamination from neighboring spots during the blocking and washing processes. Four aptamer spots were prepared in a small area of 1×4.8mm(2) with five reference spots made of blocking solution. We evaluated the thrombin binding ability of the spotted aptamer array using a multi-analysis surface plasmon resonance sensor. We prepared a disposable capillary-driven flow chip designed for on-site measurement (Miura et al., 2010) with our aptamer array and detected thrombin from phosphate-buffered saline at concentrations of 50ngmL(-1) and 1μgmL(-1) (equivalent to 1.35 and 27nM, respectively). A correlation was observed between the refractive index shift and thrombin concentration. This implies that our array preparation protocol meets the requirement for the preparation of a one-time-use chip for on-site measurement.
Collapse
Affiliation(s)
- Suzuyo Inoue
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Michiko Seyama
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan.
| | - Toru Miura
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Tsutomu Horiuchi
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Yuzuru Iwasaki
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Jun-Ichi Takahashi
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Katsuyoshi Hayashi
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| | - Emi Tamechika
- NTT Device Technology Laboratories, Nippon Telegraph and Telephone Corporation, 3-1 Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
| |
Collapse
|
18
|
Takahashi JI, Wakamiya T, Kiyoshi T, Uchiyama H, Yajima S, Kimura K, Nomura T. The complete mitochondrial genome of the Japanese honeybee, Apis cerana japonica (Insecta: Hymenoptera: Apidae). Mitochondrial DNA B Resour 2016; 1:156-157. [PMID: 33473444 PMCID: PMC7800529 DOI: 10.1080/23802359.2016.1144108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In this study, we analyzed the complete mitochondrial genome of the Japanese honeybee Apis cerana japonica. The mitochondrial genome of A. c. japonica is a circular molecule of 15 917 bp and is similar to that of A. c. cerana. It contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes and one A + T-rich control region. All protein-coding genes are initiated by ATT and ATG codons and are terminated by the typical stop codon TAA or TAG, except for the start codon of ATP8 which ends with C. All tRNA genes typically form a cloverleaf secondary structure, except for tRNA-Ser (AGN).
Collapse
Affiliation(s)
| | - Takeshi Wakamiya
- Department of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Takuya Kiyoshi
- Department of Zoology, National Museum of Nature and Science, Tokyo, Japan
| | - Hironobu Uchiyama
- NODAI Genome Research Center, Tokyo University of Agriculture, Tokyo, Japan
| | - Shunsuke Yajima
- NODAI Genome Research Center, Tokyo University of Agriculture, Tokyo, Japan.,Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Kiyoshi Kimura
- Honeybee Research Group, Animal Breeding and Reproduction Research Team, National Institute of Livestock and Grassland Science, Tsukuba, Japan
| | - Tetsuro Nomura
- Department of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| |
Collapse
|
19
|
Martin SJ, Takahashi JI, Ono M, Drijfhout FP. Is the social parasite Vespa dybowskii using chemical transparency to get her eggs accepted? J Insect Physiol 2008; 54:700-707. [PMID: 18342329 DOI: 10.1016/j.jinsphys.2008.01.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Accepted: 01/22/2008] [Indexed: 05/26/2023]
Abstract
Both avian and insect cuckoos must trick their hosts into accepting foreign eggs. In birds this is achieved through egg mimicry. Within the hornets the only known social parasite is the rare Vespa dybowskii. We investigated how the V. dybowskii queen induces tens or hundreds of host workers to accept her eggs and offspring. Since hydrocarbons function as recognition cues in social insects, we investigated these compounds from the surface of eggs and workers of V. dybowskii, both host species (V. simillima and V. crabro) and an additional four non-host species. We found that chemical mimicry of the hosts' colony odour and their eggs normally associated with wasps was not being employed by V. dybowskii. Chemical insignificance is also unlikely as the amounts of hydrocarbons extracted from parasite, host and non-host eggs were similar. Eggs of V. dybowskii may survive in part due to being chemically transparent, as methyl-branched compounds only represent a tiny proportion (<1%) of the parasites hydrocarbon profile but a large proportion (26-41%) in both host species. However, the functions of various hydrocarbon groups need to be investigated in the hornets before this new acceptance mechanism of parasite eggs and adults is understood.
Collapse
Affiliation(s)
- Stephen J Martin
- Laboratory of Apiculture and Social Insects, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
| | | | | | | |
Collapse
|
20
|
Kanzaki N, Kosaka H, Sayama K, Takahashi JI, Makino S. Sphaerularia vespae sp. nov. (Nematoda, Tylenchomorpha, Sphaerularioidea), an endoparasite of a common Japanese hornet, Vespa simillima Smith (Insecta, Hymenoptera, Vespidae). Zoolog Sci 2008; 24:1134-42. [PMID: 18348615 DOI: 10.2108/zsj.24.1134] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 07/08/2007] [Indexed: 11/17/2022]
Abstract
Sphaerularia vespae sp. nov., an endoparasite of a common Japanese hornet, Vespa simillima is described from Hokkaido, Japan, and its molecular sequence profiles are given. This newly discovered nematode appears to belong to the genus Sphaerularia, judging from its characteristic parasitic form, the uterium, which looks like a sausage with many verrucae on its surface. Sphaerularia vespae sp. nov. is distinguished from S. bombi, the only other nominal species of the genus, by the morphology of the male bursa, female tail, and anterior end of parasitic juveniles. SSU, ITS, and D2D3 (LSU) DNA sequences were determined for S. vespae sp. nov. and compared with those from related nematodes obtained from the GenBank database. The sequences from S. vespae sp. nov. were close to those of S. bombi and several another tylenchid entomoparasitic nematodes. Sphaerularia vespae sp. nov. parasitizes overwintering gynes of the hornet and practically sterilizes them, as S. bombi does for bumblebee gynes.
Collapse
Affiliation(s)
- Natsumi Kanzaki
- Forest Pathology Laboratory, Department of Forest Microbiology, Forestry and Forest Products Research Institute, Tsukuba, Ibaraki, Japan.
| | | | | | | | | |
Collapse
|
21
|
Takahashi JI. Parametric amplification of Raman-inactive lattice oscillations induced by two-color cross-beam excitation. Opt Express 2006; 14:2831-2838. [PMID: 19516419 DOI: 10.1364/oe.14.002831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The second-order Raman bands of SrTiO(3) are excited under two-color cross-beam configuration using femto-second laser pulses. Raman-inactive one-phonon waves are generated by the coherently excited large amplitude two-phonon wave. The one-phonon waves are observed as a train of visible light spots, the frequency steps of which are coincident with the frequencies of the one-phonon modes. In order to understand the mechanism, a model of three-wave interaction among one two-phonon wave and two one-phonon waves is proposed.
Collapse
|
22
|
Yamada K, Tsuchizawa T, Watanabe T, Takahashi JI, Fukuda H, Takahashi M, Shoji T, Uchiyama S, Tamechika E, Itabashi SI, Morita H. Silicon wire waveguiding system: Fundamental characteristics and applications. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/ecjb.20210] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
23
|
Fukuda H, Yamada K, Shoji T, Takahashi M, Tsuchizawa T, Watanabe T, Takahashi JI, Itabashi SI. Four-wave mixing in silicon wire waveguides. Opt Express 2005; 13:4629-4637. [PMID: 19495378 DOI: 10.1364/opex.13.004629] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report the observation of four-wave mixing phenomenon in a simple silicon wire waveguide at the optical powers normally employed in communications systems. The maximum conversion efficiency is about -35 dB in the case of a 1.58-cm-long silicon wire waveguide. The nonlinear refractive index coefficient is found to be 9x10-18 m2/W. This value is not negligible for dense wavelength division multiplexing components, because it predicts the possibility of large crosstalk. On the other hand, with longer waveguide lengths with smaller propagation loss, it would be possible to utilize just a simple silicon wire for practical wavelength conversion. We demonstrate the wavelength conversion for data rate of 10-Gbps using a 5.8-cm-long silicon wire. These characteristics are attributed to the extremely small core of silicon wire waveguides.
Collapse
|
24
|
Takahashi JI, Kawabe Y, Hanamura E. Generation of a broadband spectral comb with multiwave mixing by exchange of an impulsively stimulated phonon. Opt Express 2004; 12:1185-1191. [PMID: 19474937 DOI: 10.1364/opex.12.001185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A broadband spectral comb is generated around the third harmonics of incident light with the nondegenerate, impulsively stimulated Raman scattering technique using ultrashort light pulses. The comb has a spectral width of more than 4000 cm(-1), and its envelope becomes smooth as the light powers are increased. It consists of discrete lines, the spacing of which is equal to the frequency of the Raman-active phonon mode, even though the frequency of the phonon mode is far smaller than the frequency difference between the two incident light pulses. The multiline structure is generated with multiwave mixing by exchange of the impulsively stimulated phonon among the signals.
Collapse
|
25
|
Hikichi T, Kitaya N, Takahashi JI, Ishiko S, Mori F, Yoshida A. Association of preoperative photoreceptor displacement and improved central scotoma after idiopathic macular hole surgery. Ophthalmology 2002; 109:2160-4. [PMID: 12414433 DOI: 10.1016/s0161-6420(02)01224-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
OBJECTIVE To investigate the relationship between preoperative photoreceptor displacement and postoperative scotoma after unilateral idiopathic macular hole surgery. DESIGN Prospective nonrandomized comparative self-controlled trial. PARTICIPANTS Twenty patients who underwent successful surgery for unilateral idiopathic macular hole participated in the study. METHODS Kinetic perimetry using red and green filter glasses, black binocular fixation targets, and red and green selective monocular stimuli was performed preoperatively. Scanning laser ophthalmoscope (SLO) microperimetry was performed preoperatively and postoperatively. RESULTS Sixteen patients had photoreceptor displacement preoperatively. In preoperative SLO microperimetry, all eyes with a macular hole had a scotoma; postoperatively, 12 of 16 had no scotoma. All four eyes with no preoperative photoreceptor displacement were noted to have a postoperative scotoma. The prevalence of postoperative scotoma in patients with preoperative photoreceptor displacement (4 of 16; 25%) was significantly lower than that in patients without preoperative photoreceptor displacement (4 of 4; 100%) (P = 0.03). CONCLUSIONS The presence or absence of photoreceptor displacement preoperatively should affect postsurgical visual function. Photoreceptor damage may occur in eyes without photoreceptor displacement preoperatively, resulting in scotoma postoperatively.
Collapse
Affiliation(s)
- Taiichi Hikichi
- Department of Ophthalmology, Asahikawa Medical College, Asahikawa, Japan.
| | | | | | | | | | | |
Collapse
|
26
|
Takahashi JI, Hagita K, Kohn K, Tanabe Y, Hanamura E. Anomalously broad Raman scattering spectrum due to two-magnon excitation in hexagonal YMnO3. Phys Rev Lett 2002; 89:076404. [PMID: 12190539 DOI: 10.1103/physrevlett.89.076404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2001] [Indexed: 05/23/2023]
Abstract
A strong and broad Raman scattering (RS) spectrum is observed from two-magnon processes in YMnO3. The spectrum is analyzed by taking account (i) the magnon-exciton interaction and (ii) the magnon-phonon coupling in the intermediate state. Anomalous broadening of the RS is attributed to the large superexchange interaction between manganite ions and subsequent modification of magnons under the presence of the exciton and phonons in the intermediate state.
Collapse
Affiliation(s)
- Jun-Ichi Takahashi
- Japan Science and Technology Corporation (CREST), 758-65 Bibi, Chitose, Hokkaido 066-8655, Japan
| | | | | | | | | |
Collapse
|
27
|
Takano Y, Kaneko T, Kobayashi K, Takahashi JI, Pizzarello S, Cronin JR. [Formation of asymmetric (correction of asymmetic) bioorganics by synchrotron radiation]. Biol Sci Space 2001; 15:236-7. [PMID: 11997620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- Y Takano
- Department of Chemistry and Biotechnology, Yokohama National University
| | | | | | | | | | | |
Collapse
|
28
|
Kobayashi K, Masuda H, Ushio KI, Ohashi A, Yamanashi H, Kaneko T, Takahashi JI, Hosokawa T, Hashimoto H, Saito T. Formation of bioorganic compounds in simulated planetary atmospheres by high energy particles or photons. Adv Space Res 2001; 27:207-215. [PMID: 11605633 DOI: 10.1016/s0273-1177(01)00049-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Various types of organic compounds have been detected in Jupiter, Titan, and cometary coma. It is probable that organic compounds were formed in primitive Earth and Mars atmospheres. Cosmic rays and solar UV are believed to be two major energy sources for organic formation in space. We examined energetics of organic formation in simulated planetary atmospheres. Gas mixtures including a C-source (carbon monoxide or methane) and a N-source (nitrogen or ammonia) was irradiated with the followings: High energy protons or electrons from accelerators, gamma-rays from 60Co, UV light from a deuterium lamp, and soft X-rays or UV light from an electron synchrotron. Amino acids were detected in the products of particles, gamma-rays and soft X-rays irradiation from each gas mixture examined. UV light gave, however, no amino acid precursors in the gas mixture of carbon monoxide, nitrogen and nitrogen. It gave only a trace of them in the gas mixture of carbon monoxide, ammonia and water or that of methane, nitrogen and water. Yield of amino acid precursors by photons greatly depended on their wavelength. These results suggest that nitrogen-containing organic compounds like amino acid precursors were formed chiefly with high energy particles, not UV photons, in Titan or primitive Earth/Mars atmospheres where ammonia is not available as a predominant N-source.
Collapse
Affiliation(s)
- K Kobayashi
- Department of Chemistry and Biotechnology, Yokohama National University, Hodogaya-ku, Yokohama 240-8501, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Utsumi Y, Takahashi JI, Hosokawa T. Synchrotron-radiation-induced formation of salt particles on an X-ray lithography mask. J Synchrotron Radiat 1998; 5:1141-1143. [PMID: 15263772 DOI: 10.1107/s0909049597017603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/21/1997] [Indexed: 05/24/2023]
Abstract
The suppression and removal of contaminants on X-ray masks are required for the application of X-ray lithography to practical semiconductor production, because contamination is easily transferred to the replicated resist patterns and degrades the LSI patterns. In order to study contamination of a Ta/SiN X-ray mask, its growth process was investigated using an atmospheric reaction chamber and in situ observation apparatus for gases at atmospheric pressure. It was found that the contamination particles were ammonium sulfate and oxalate. The sources of the salt particle were also identified.
Collapse
Affiliation(s)
- Y Utsumi
- NTT System Electronics Laboratories, 3-1, Morinosato-Wakamiya, Atsugi, Kanagawa 243-01, Japan
| | | | | |
Collapse
|
30
|
Takahashi JI, Utsumi Y, Hosokawa T, Ushiki J, Tadano T. A beamline for photochemical processes at atmospheric pressure. J Synchrotron Radiat 1998; 5:548-550. [PMID: 15263574 DOI: 10.1107/s0909049597017585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/21/1997] [Indexed: 05/24/2023]
Abstract
A beamline especially designed for atmospheric photochemical reactions has been constructed at the NTT synchrotron radiation facility. By inserting a buffer helium chamber with Be and Si(3)N(4) partition windows between the beamline and the reaction chamber, studies can be performed without the differential pumping systems normally used in existing photochemistry beamlines. The reaction chamber is equipped with a gas supply system and analysis systems to investigate gas-phase and surface reactions. Purging using dry purified gases in combination with water-bubbling gives effective control of water concentration in the reaction chamber.
Collapse
Affiliation(s)
- J I Takahashi
- NTT System Electronics Laboratories, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-01, Japan
| | | | | | | | | |
Collapse
|
31
|
Urisu T, Takahashi JI, Utsumi Y, Akazawa H. Synchrotron radiation-stimulated photochemical reaction and its application to semiconductor processes. Appl Organomet Chem 1991. [DOI: 10.1002/aoc.590050405] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|