• 한국경제지리학회지
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• 제11권2호
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• pp.251-271
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• 2008

멕시코의 마낄라도라산업은 1980년대 및 1990년대 멕시코의 경제위기로 인한 노동비의 감소, NAFTA 발효로 인한 멕시코의 북미시장으로의 진출 가능성의 제고 등으로 인해 성장하였다. 초기 마낄라도라산업은 멕시코의 북부 접경지역에서 젊은 여성 노동력을 바탕으로 섬유 및 전자 조립 부분을 중심으로 입지하기 시작하였으나 1980년대 이후 생산액 및 고용면에서 기계 및 전자 부문의 비중이 증가되었고 남성의 노동력 참여율도 높아졌으며 분포 지역 또한 25개 주로 확대되었다. 멕시코의 마낄라도라 산업에서 가장 주요한 지역은 치와와와 바하 칼리포르니아 주이며 주요 도시는 씨우다드 후아레스와 티후아나이다. 마낄라도라산업은 1990년대 후반 생산액과 고용면에서 비약적인 증가를 하여 2000년을 전후하여 전성기를 맞았으나, 이후 생산액 측면에서는 약간의 감소가, 고용측면에서는 비교적 큰 감소가 나타났다. 마낄라도라산업의 입지 가능 범위는 멕시코 모든 지역으로 확대되었지만 아직도 대부분의 마낄라도라산업은 북부 접경 6개주를 중심으로 입지하고 있다. 섬유산업의 경우 마낄라도라산업의 대표적인 산업으로서 마낄라도라산업 성장의 초기에 해당하는 지역의 대부분이 섬유산업 중심이다. 따라서 섬유산업은 마낄라도라 산업 전반과 분포패턴이 유사하게 나타났다. 그러나 기계 및 전자 산업의 경우 북부 접경주로의 집중이 매우 두드러지며 기존 공업지대가 입지한 지역에 분포하는 특성이 나타났다. 산업별 고용 변화를 살펴본 결과 기계 및 전자 부문의 고용이 가장 많았고 섬유 부문이 그 뒤를 따랐다. 기타 부문 중 특기할 점은 서비스업의 꾸준한 증가이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.271-271
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• 2007

• 대한원격탐사학회지
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• 제27권3호
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• pp.235-258
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• 2011

The purpose of this study is to investigate climatological variations from the temporal and spatial surface particulate organic carbon (POC) estimates based on SeaWiFS spectral radiance, and to determine the physical mechanisms that affect the distribution of pac in the Gulf of Mexico. 7-year monthly mean values of surface pac concentration (Sept. 1997 - Dec. 2004) were estimated from Maximum Normalized Difference Carbon Index (MNDCI) algorithm using SeaWiFS data. Synchronous 7-year monthly mean values of remote sensing data (sea surface temperature (SST), sea surface wind (SSW), sea surface height anomaly (SSHA), precipitation rate (PR)) and recorded river discharge data were used to determine physical forcing factors. The spatial pattern of POC was related to one or more factors such as river runoff, wind-derived current, and stratification of the water column, the energetic Loop Current/Eddies, and buoyancy forcing. The observed seasonal change in the POC plume's response to wind speed in the western delta region resulted from seasonal changes in the upper ocean stratification. During late spring and summer, the low-density river water is heated rapidly at the surface by incoming solar radiation. This lowers the density of the fresh-water plume and increases the near-surface stratification of the water column. In the absence of significant wind forcing, the plume undergoes buoyant spreading and the sediment is maintained at the surface by the shallow pycnocline. However, when the wind speed increases substantially, wind-wave action increases vertical motion, reducing stratification, and the sediment were mixed downward rather than spreading laterally. Maximum particle concentrations over the outer shelf and the upper slope during lower runoff seasons were related to the Loop Current/eddies and buoyancy forcing. Inter-annual differences of POC concentration were related to ENSO cycles. During the El Nino events (1997-1998 and 2002-2004), the higher pac concentrations existed and were related to high runoffs in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico. During La Nina conditions (1999-2001), low Poe concentration was related to normal or low river discharge, and low PM/nutrient waters in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico.

• Nutrition Research and Practice
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• 제15권sup1호
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• pp.32-40
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• 2021

BACKGROUND/OBJECTIVES: Considering the high number of deaths from coronavirus disease 2019 (COVID-19) in Latin American countries, together with multiple factors that increase the prevalence of vitamin D deficiency, we aimed to determine 25-hydroxyvitamin D (25[OH]D) levels and its association with mortality in patients with critical COVID-19. SUBJECTS/METHODS: This was a prospective observational study including adult patients with critical COVID-19. Data, including clinical characteristics and 25(OH)D levels measured at the time of intensive care unit admission, were collected. All patients were followed until hospital discharge or in-hospital death. The patients were divided into those surviving and deceased patient groups, and univariate and multivariate logistic regression analyses were performed to determine independent predictors of in hospital mortality. RESULTS: The entire cohort comprised 94 patients with critical COVID-19 (males, 59.6%; median age, 61.5 years). The median 25(OH)D level was 12.7 ng/mL, and 15 (16%) and 79 (84%) patients had vitamin D insufficiency and vitamin D deficiency, respectively. The median serum 25(OH)D level was significantly lower in deceased patients compared with surviving (12.1 vs. 18.7 ng/mL, P < 0.001). Vitamin D deficiency was present in 100% of the deceased patients. Multivariate logistic regression analysis revealed that age, body mass index, other risk factors, and 25(OH)D level were independent predictors of mortality. CONCLUSIONS: Vitamin D deficiency was present in 84% of critical COVID-19 patients. Serum 25(OH)D was independently associated with mortality in critical patients with COVID-19.

• Parasites, Hosts and Diseases
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• 제55권1호
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• pp.81-84
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• 2017

Trypanosoma cruzi is the etiological agent of Chagas disease. Epimastigote forms of T. cruzi can be readily cultured in axenic conditions. Ethanol and dimethyl sulfoxide (DMSO) are commonly used solvents employed as vehicles for hydrophobic compounds. In order to produce a reference plot of solvent dependent growth inhibition for T. cruzi research, the growth of epimastigotes was analyzed in the presence of different concentrations of ethanol (0.1-4.0%) and DMSO (0.5-7.5%). The ability of the parasites to resume growth after removal of these solvents was also examined. As expected, both ethanol and DMSO produced a dose-dependent inhibition of cellular growth. Parasites could recover normal growth after 9 days in up to 2% ethanol or 5% DMSO. Since DMSO was better tolerated than ethanol, it is thus recommended to prefer DMSO over ethanol in the case of a similar solubility of a given compound.

• Parasites, Hosts and Diseases
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• 제52권4호
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• pp.429-433
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• 2014

To identify sequences of Entamoeba histolytica associated with the development of amebic liver abscess (ALA) in hamsters, subtractive hybridization of cDNA from E. histolytica HM-1:IMSS under 2 growth conditions was performed: 1) cultured in axenic medium and 2) isolated from experimental ALA in hamsters. For this procedure, 6 sequences were obtained. Of these sequences, the mak16 gene was selected for amplification in 29 cultures of E. histolytica isolated from the feces of 10 patients with intestinal symptoms and 19 asymptomatic patients. Only 5 of the 10 isolates obtained from symptomatic patients developed ALA and amplified the mak16 gene, whereas the 19 isolates from asymptomatic patients did not amplify the mak16 gene nor did they develop ALA. Based on the results of Fisher's exact test (P<0.001), an association was inferred between the presence of the mak16 gene of E. histolytica and the ability to develop ALA in hamsters and with the patient's symptoms (P=0.02). The amplification of the mak16 gene suggests that it is an important gene in E. histolytica because it was present in the isolates from hamsters that developed liver damage.

• Smart Structures and Systems
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• 제5권4호
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• pp.483-494
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• 2009

Damage detection has been proven to be a challenging task in structural health monitoring (SHM) due to the fact that damage cannot be measured. The difficulty associated with damage detection is related to electing a feature that is sensitive to damage occurrence and evolution. This difficulty increases as the damage size decreases limiting the ability to detect damage occurrence at the micron and submicron length scale. Damage detection at this length scale is of interest for sensitive structures such as aircrafts and nuclear facilities. In this paper a new photonic sensor based on photonic crystal (PhC) technology that can be synthesized at the nanoscale is introduced. PhCs are synthetic materials that are capable of controlling light propagation by creating a photonic bandgap where light is forbidden to propagate. The interesting feature of PhC is that its photonic signature is strongly tied to its microstructure periodicity. This study demonstrates that when a PhC sensor adhered to polymer substrate experiences micron or submicron damage, it will experience changes in its microstructural periodicity thereby creating a photonic signature that can be related to damage severity. This concept is validated here using a three-dimensional integrated numerical simulation.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.914-920
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• 2011

Vibrio cholerae utilizes mannitol through an operon of the phosphoenolpyruvate-dependent phosphotransferase (PTS) type. A gene, mtlD, encoding mannitol-1-phosphate dehydrogenase was identified within the 3.9 kb mannitol operon of V. cholerae. The mtlD gene was cloned from V. cholerae O395, and the recombinant enzyme was functionally expressed in E. coli as a $6{\times}$His-tagged protein and purified to homogeneity. The recombinant protein is a monomer with a molecular mass of 42.35 kDa. The purified recombinant MtlD reduced fructose 6-phosphate (F6P) using NADH as a cofactor with a $K_m$ of $1.54{\pm}0.1$ mM and $V_{max}$ of $320.8{\pm}7.81\;{\mu}mol$/min/mg protein. The pH and temperature optima for F6P reduction were determined to be 7.5 and $37^{\circ}C$, respectively. Using quantitative real-time PCR analysis, mtlD was found to be constitutively expressed in V. cholerae, but the expression was up-regulated when grown in the presence of mannitol. The MtlD expression levels were not significantly different between V. cholerae O1 and non-O1 strains.

• Advances in concrete construction
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• 제5권6호
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• pp.563-573
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• 2017

Transparency, excellent toughness, thermal stability and a very good dimensional stability make Polycarbonate (PC) one of the most widely used engineering thermoplastics. Polycarbonate market include electronics, automotive, construction, optical media and packaging. One alternative for reducing the environmental pollution caused by polycarbonate from electronic waste (e-waste), is to use it in cement concretes. In this work, physical and chemical characterization of recycled polycarbonate from electronic waste was made, through the analysis by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM). Then cement concrete was made with Portland cement, sand, gravel, water, and this recycled polycarbonate. Specimens without polycarbonate were produced for comparison purposes. The effect of the particle sizes and concentrations of recycled polycarbonate within the concrete, on the compressive strength and density was studied. Results show that compressive strength values and equilibrium density of concrete depend on the polycarbonate particle sizes and its concentrations; particularly the highest compressive strength values were 20% higher than that for concrete without polycarbonate particles. Moreover, morphological, structural and crystallinity characteristics of recycled polycarbonate, are suitable for to be mixed into concrete.

• Archives of Plastic Surgery
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• 제48권3호
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• pp.254-260
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• 2021

Background Myelomeningocele is a frequently seen condition at tertiary care hospitals. Its treatment involves a variety of plastic reconstructive techniques. Herein, we present a series of myelomeningocele patients treated using keystone flaps. Methods We gathered information regarding soft tissue reconstruction and the use of bilateral keystone flaps to treat myelomeningocele patients. We obtained data from clinical records and recorded the demographic characteristics of mothers and children with the condition. The size, level of defect, and complications detected during the follow-up were analyzed. Results A series of seven patients who underwent bilateral keystone flaps for myelomeningocele closure was analyzed. There were no cases of midline or major dehiscence, flap loss, necrosis, surgical site infections, or cerebrospinal fluid leakage. No revision procedures were performed. Minor complications included one case with minimal seroma and three cases with areas of peripheral dehiscence that healed easily using conventional measures. Conclusions The use of keystone flaps is an adequate option for closure of dorsal midline soft tissue defects related to myelomeningocele. This technique offers predictable results with an acceptable spectrum of complications. Robust blood flow can be predicted based upon anatomical knowledge.