• Ocean Systems Engineering
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• 제2권2호
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• pp.99-113
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• 2012

Steel Catenary Risers (SCR) are the simplest and often the most economic solution compared to other riser types such as flexible pipe, riser towers, top tensioned risers, etc. The top of a SCR is connected to the host platform riser porch. The other end of the SCR connects to flowlines from subsea wells. The riser touchdown point (TDP), which is the location along the riser where contact with the sea floor first occurs, exhibits complex behaviors and often results in compression and fatigue related issues. Heave dynamic responses of semisubmersibles in extreme and operating sea states are crucial for feasibility of SCR application. Recent full field measurement results of a deep draft semisubmersible in Hurricane Gustav displayed the considerable discrepancies in heave responses characteristics between the measured and the simulated results. The adequacy and accuracy of the simulated results from recognized commercial software should be examined. This finding raised the awareness of shortcomings of current commercial software and potential risk in mega investment loss and environmental pollutions due to SCR failures. One main objective of this paper is to attempt to assess the importance and necessity of accounting for viscous effects during design and analysis by employing indicator of viscous parameter. Since viscous effects increase with nearly third power of significant wave height, thus newly increased metocean criteria per API in central Gulf of Mexico (GoM) and even more severe environmental conditions in Western Australia (WA) call for fundamental enhancements of the existing analysis tools to ensure reliable and robust design. Furthermore, another aim of this paper is to address the impacts of metocean criteria and design philosophy on semisubmersible hull sizing in WA and GoM.

• Mycobiology
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• 제46권2호
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• pp.92-100
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• 2018

The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3805-3809
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• 2014

Background: In Mexico, breast cancer (BCa) is the leading type of cancer in women. Cytochrome P450 (CYP450) is a superfamily of major oxidative enzymes that metabolize carcinogens and many antineoplastic drugs. In addition, these enzymes have influence on tumor development and tumor response to therapy. In this report, we analyzed the protein expression in patients with BCa and in healthy women. Links with some clinic-pathological characteristic were also assessed. Materials and Methods: Immunohistochemical analyses were conducted on 48 sets of human breast tumors and normal breast tissues enrolled in Hospital Militar de Especialidades de la Mujer y Neonatologia and Hospital Central Militar, respectively, during the time period from 2010 to 2011. Informed consent was obtained from all participants. Statistical analysis was performed using ${\chi}^2$ or Fisher exact tests to estimate associations and the Mann Whitney U test for comparison of group means. Results: We found a significant CYP3A4 overexpression in BCa stroma and gland regions in comparison with healthy tissue. A significant association between protein expression with smoking, alcoholism and hormonal contraceptives use was also observed. Additionally, we observed estrogen receptor (ER) and progesterone receptor (PR) positive association in BCa. Conclusions: We suggest that CYP3A4 expression promotes BCa development and can be used in the prediction of tumor response to different treatments. One therapeutic approach may thus be to block CYP3A4 function.

• 한국지역지리학회지
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• 제11권2호
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• pp.291-311
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• 2005

스페인의 전통 토지운영 체제의 하나였던 대농장은 1520년대 신대륙 개척기에 제국군대, 성직자, 상인은 물론 구대륙 생태계의 구성요소인 다양한 동식물과 함께 멕시코를 비롯한 현재의 중남미에 이식되었다. 중세기 스페인 남부의 대농체제인 라티푼디오의 전통과 신대륙의 자연환경이 접목된 아시엔다는 미국 남부의 플랜테이션에 비유되며 식민지시대가 막을 내리는 1821년에 이미 멕시코 농촌의 보편적인 경관으로 자리잡기에 이른다. 아시엔다는 식민지시대 멕시코를 일컫는 뉴-스페인 중부지방에 집중적으로 분포하였고, 입지결정에는 건조한 환경에서 필수적으로 요구되는 식수 및 농업용수가 깊이 관여하였으며, 수행하는 내부 경제출동의 종류에 따라 곡물아시엔다, 가축아시엔다, 광산아시엔다, 아네킨아시엔다 등 다양한 유형으로 분류된다. 대토지소유자, 농장관리자, 임노동 소작인을 주요 구성원으로 하는 아시엔다는 준 자급자족적 취락으로서 주거는 물론 종교, 농업, 문화전파 등 다양한 기능을 수행하였다. 식민지시대 멕시코의 아시엔다는 자본주의의 확산과 함께 전환기를 맞게되고 이를 계기로 내부적으로 대대적인 변형을 경험하는데, 축소된 형태이지만 오늘날 대농장과 영세농지를 특징으로 하는 멕시코 농촌경관의 일부로 잔존해 있다.

• Journal of Forest and Environmental Science
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• 제37권4호
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• pp.292-303
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• 2021

Studies that relate the structure of tropical regrowth vegetation to soil properties are generally lacking in the literature. This study proposes three indices for assessing the structural regeneration of secondary forests. They are: (1) the tree diameter class, (2) the plant life form and (3) the woody/herbaceous plants ratio indices. They were applied to assess the regeneration status of forest regrowth vegetation (aged 1-10 years), derived savanna regrowth vegetation in south western Nigeria, and to secondary forests in different stages of succession in Columbia and Venezuela, Bolivia, Mexico in South and Central America and semi-arid savanna in Ethiopia and seasonal deciduous forest successional stages in India. In all the cases, the indices increased with increasing age of regrowth vegetation and hence, with increasing structural complexity of regenerating vegetation. The tree diameter class index increased from 32.1% in a 9-year secondary forest to 69.0% in an 80-year-old secondary forest in Columbia and Venezuela and from 0.4% in a 1-year fallow to 20.9% in 10-year regrowth vegetation in southwestern Nigeria. In semi-arid savanna in northern Ethiopia, the woody/herbaceous plants ratio index increased from 18.1% in a 5-year protected grazing enclosure to 75.1% in 15-year protected enclosure, relative to the status of 20-year enclosure. The indices generally had correlations of 0.6-0.90 with species richness and Simpson's/Margalef's species diversity, implying that they are appropriate measures of ecosystem development over time. The proposed indices also had strong and positive correlations with soil organic carbon and nutrients. They are therefore, significant indicators of fertility status.

• Fisheries and Aquatic Sciences
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• 제27권5호
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• pp.306-313
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• 2024

The genus Chirostoma is endemic from the Mesa Central of Mexico. It is conformed of 18 species and six subspecies. Five species are in some category of risk, because of this, Chirostoma jordani is an excellent model species to implement biotechnologies like gametes cryopreservation. Aim of present study was to evaluate fertilizing capacity of cryopreserved C. jordani sperm, as alternative to conservation and assisted reproduction in this specie and genus. Males and females were collected from wild Atlangatepec dam stock, Tlaxcala State, Mexico. Seminal quality was evaluated in fresh and cryopreserved semen with three cryoprotective agents (CPAs): 10% dimethyl sulfoxide (DMSO), 10% methanol (MeOH), 14% ethylene glycol (EG) and it was determined its post-thaw fertilizing capacity. Sperm motility percentage decreased during cryopreservation process (p < 0.05). There were not significant differences in post-thaw motility percentage between EG (53.5 ± 1.9%) and MeOH (53.3 ± 1.3%), but DMSO (50.3 ± 0.5%) was significantly different (p < 0.05). Results showed that 0.2 μL fresh semen were enough to fertilize 100% oocytes (n = 60). 10 μL DMSO and 5 μL MeOH and EG cryopreserved semen were necessary to fertilize oocytes 100% (n = 60) (p < 0.05). Cryopreservation and fertilization protocol for C. jordani sperm was efficient and it could be used for its assisted reproduction.

• 천문학논총
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• 제30권2호
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• pp.163-167
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• 2015

We have carried out integral field unit (IFU) spectroscopy of $H{\alpha}$, [$N{\small{II}}$] and [$O{\small{III}}$] emission lines for a sample of Galactic planetary nebulae (PNe) with Wolf-Rayet (WR) stars and weak emission-line stars (wels). Comparing their spatially-resolved kinematic observations with morpho-kinematic models allowed us to disentangle their three-dimensional gaseous structures. Our results indicate that these PNe have axisymmetric morphologies, either bipolar or elliptical. In many cases the associated kinematic maps for the PNe around hot central stars also reveal the presence of so-called fast low-ionization emission regions.

• 식물분류학회지
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• 제53권1호
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• pp.60-64
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• 2023

Ipomoea cristulata Hallier f. (Convolvulaceae), native to the desert regions of the central USA to Mexico, was newly found in Gojeong-ri, Deokgwa-myeon, Namwon-si, Jeollabuk-do. This species can be distinguished from I. coccinea by leaves with 3-5 lobes, hirsute distributed adaxially, and corolla entirely red or orange-red. Its Korean name is 'Nabi-ip-yu-hong-cho' based on its butterfly-shaped leaves. We provide a detailed description, photographs, habitat details, and a taxonomic key to related taxa.

• 대한지리학회지
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• 제40권5호
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• pp.571-583
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• 2005

본 연구에서는 중부 멕시코 바히오 지방에 위치한 바예 데 산티아고 시의 마르 호수 중 하나인 호야 산 니콜라스에서 채취한 시료를 분석하여 고환경을 복원하였다. 마르 호수 퇴적물은 고해상의 고환경 복원이 가능하기 때문에 널리 이용되고 있다. 연구방법으로 화분, 동위원소, 지화학적 분석 등을 시도하였다. 분석결과를 보면, 11,000년 전에서 8,900년 전까지 기후는 건조하였고, 8,900 년 전부터 7,000 년 전까지는 습했으며, 7,000년 전부터 4,000 년 전까지 건조하였고, 4,000년 전부터 현재까지는 다시 습했다. 두 건조한 기간(ca. 11,000 - ca. 8,900 cal yr B.P., ca. 7,000 - ca. 4,000 cal yr B.P.)에 소나무 화분이 비율이 아주 높게 나온다. 이는 건조한 기후로 호수가 마르면서 전체적으로 화분이 파괴되었음 의미한다. 다시 말하면, 가장 단단한 화분중의 하나인 소나무 화분은 건조한 상태에서 다른 화분보다 상대적으로 잘 버티므로 소나무 화분의 높은 비율은 기후가 건조했음을 뜻한다고 볼 수 있다. 두 건조 시기에는 호숫물이 말라 퇴적이 중단된 기간이 있었을 것으로 사료된다.

• 한국초지조사료학회지
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• 제36권2호
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• pp.142-149
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• 2016

'신성'은 2015년에 농촌진흥청 국립식량과학원에서 육성되었다. 계통은 1998년 멕시코의 국제밀옥수수연구소(CIMMYT)에서 'ASNO'와 'ARDI_3'의 잡종에 'RIZO_7'을 교잡한 잡종과 'RONDO'과 'ERIZO_11'를 교잡한 잡종에 'KISSA_4'를 교잡한 잡종 간의 복교잡을 실시하여 작성되었으며, 고세대 계통인 'CTSS98Y00019S-0MXI-B-3-3-5'는 2010년부터 2012년까지 3년간 생산력검정시험을 실시하였다. 이 계통은 숙기가 빠르고 건물수량이 많아 '익산47호'로 계통명을 부여하고 2013년부터 2015년까지 3년간에 걸쳐 제주, 익산, 청원, 예산, 강진, 대구 및 진주 등 7개 지역에서 지역적응시험을 실시하였다. 그 결과 '익산47호'는 기존품종에 비해 출수가 빠르고, 도복과 습해 등 내재해성이 강하며, 종실 생산성이 우수하여 2015년 8월 농촌진흥청 농작물 직무육성 신품종선정위원회에서 직무육성품종으로 결정되었고, 품종명이 '신성'으로 명명되었으며, 그 특성은 다음과 같다. 신품종 '신성'은 담녹색 잎, 황색 줄기, 갈색의 종실을 가졌다. 출수기가 전국 평균 4월 24일로 표준품종인 '신영' 보다 3일 빨랐다. '신성'은 '신영'과 대등하게 한해와 도복에 강하였으며, 습해, 흰가루병 및 잎녹병 등에 저항성이었다. 건물수량은 ha당 평균 15톤으로 15.5톤인 '신영'에 비해 3% 낮았다. '신성'은 '신영'에 비해 조단백질 함량이 6.7%로 높았으며, NDF, ADF 및 TDN도 각각 34.6%, 58.6%, 61.6%으로 '신영'과 대등한 수준이었다. '신성'은 '신영'에 비해 1수립수, $m^2$당 수수가 많고 $1{\ell}$중이 무거워 종실수량이 ha당 7.2톤으로 '신영'의 5.8톤 보다 25%가 많았다. 적응지역은 1월 최저평균기온이 $-10^{\circ}C$ 이상인 지역이면 전국 어느 곳에서나 재배가 가능하다.