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1.
Opt Express ; 32(7): 12276-12290, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571055

RESUMEN

Pre-pedestal generation is observed in a 0.35-PW laser front end coming from a post-pedestal via instantaneous gain and pump depletion in an optical parametric amplifier during chirped-pulse amplification. Generalized simulations show how this effect arises from gain nonlinearity and applies to all optical parametric chirped-pulse-amplification systems with a post-pedestal. An experiment minimizing the effect of B-integral is used to isolate and study the newly observed conversion of a continuous post-pedestal into a continuous pre-pedestal. Matching numerical simulations confirm experimental results and additionally reveal how third-order dispersion largely controls the slope of the generated pre-pedestal.

2.
Opt Express ; 31(15): 24785-24795, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37475297

RESUMEN

Optical parametric chirped-pulse amplification (OPCPA) using high-energy Nd:glass lasers has the potential to produce ultra-intense pulses (>1023 W/cm2). We report on the performance of the final high-efficiency amplifier in an OPCPA system based on large-aperture (63 × 63-mm2) partially deuterated potassium dihydrogen phosphate (DKDP) crystals. The seed beam (180-nm bandwidth, 110 mJ) was provided by the preceding OPCPA stages. A maximum pump-to-signal conversion efficiency of 41% and signal energy up to 13 J were achieved with a 52-mm-long DKDP crystal due to the flattop super-Gaussian pump beam profile and flat-in-time pulse shape.

3.
Rhinology ; 61(4): 338-347, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37083114

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by chronic eosinophilic inflammation and new bone formation (NBF). These processes may be associated with each other in the pathogenesis and influence the severity and prognosis of the disease. However, it is still unclear how eosinophilic inflammation is involved in the NBF. METHODOLOGY: Sinus bone cells were isolated from ethmoid bone tissues of patients with CRSwNP and controls. Transforming growth factor beta 1 (TGFß1) and alkaline phosphatase (ALP) expression in sinus bone cells was determined using quantitative RT-PCR, immunoblotting, and immunohistochemistry. The co-localization of TGFß1 with eosinophils was assessed by immunofluorescence staining. Sinus bone cells were co-cultured with eosinophils (Eol-1 cell line), which were differentiated with butyrate, to measure the osteoblast differentiation activity of sinus bone cells. RESULTS: TGFß1 expression was increased in sinus bone tissues and correlated with CT scores in CRSwNP. TGFß1 was also increased in the submucosa of CRSwNP and co-localized predominantly with eosinophils compared with neutrophils Differentiated Eol-1 cells-derived TGFß1 increased ALP expression in sinus bone cells. Treatment with a TGFß inhibitor attenuated TGFß1-induced ALP expression and staining in sinus bone cells of CRSwNP, leading to loss of bone formation. CONCLUSIONS: Eosinophil-derived TGFß1 was enriched in the submucosa of CRSwNP, which induced ALP expression in sinus bone cells and NBF. Therefore, eosinophil-derived TGFß1 may mediate aberrant bone remodeling in CRSwNP.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Eosinófilos , Rinitis/complicaciones , Rinitis/patología , Factor de Crecimiento Transformador beta , Pólipos Nasales/complicaciones , Pólipos Nasales/patología , Osteogénesis , Sinusitis/complicaciones , Sinusitis/patología , Inflamación/patología , Enfermedad Crónica
4.
Opt Express ; 30(8): 12995-13008, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35472923

RESUMEN

We present a theoretical and experimental analysis of the signal phase introduced by the pump-beam wavefront and spatial profile during optical parametric amplification (OPA) process. The theory predicts the appearance of an additional wavefront in the amplified signal beam that is proportional to the spatial derivative of the pump-beam wavefront. The effect of the pump-beam profile on the signal-beam wavefront is also investigated. Our experiments tested these theoretical predictions by comparing the wavefront of the signal beam before and after amplification in a multi-joule broadband OPA. The measured signal wavefront was shown to have the expected dependence on the pump-beam profile and wavefront. These results can be considered when designing petawatt-scale ultrabroadband optical parametric chirped-pulse-amplification systems.

5.
Opt Express ; 29(24): 40240-40258, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809370

RESUMEN

In optical parametric chirped-pulse amplification (OPCPA), pump temporal intensity modulation is transferred to the chirped-signal spectrum via instantaneous parametric gain and results in contrast degradation of the recompressed signal. We investigate, for the first time to our knowledge, the pump-to-signal noise transfer in a two-stage ultra-broadband OPCPA pumped by a single laser and show the dependence of pump-induced signal noise, characterized both before and after pulse compression, on the difference in pump-seed delay in the two stages. We demonstrate an up-to-15-dB reduction of the pump-induced contrast degradation via pump-seed delay optimization. Experiments and simulations show that, even when parametric amplifiers are operated in saturation, the pump-seed delay can be used to minimize the pump-induced contrast degradation that is attributed largely to the noises from the unsaturated edges of the pulse and that of the beam.

6.
Osteoporos Int ; 30(7): 1533-1536, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31016352

RESUMEN

This case report describes a case of an elderly woman diagnosed with acute osteoporotic vertebral compression fracture (OVCF) at thoracic spine after using an electrical automated massage chair (EAMC). Care should be taken when using an EAMC, especially by those with or at risk of developing osteoporosis. Osteoporotic vertebral compression fracture (OVCF) is a common problem among elderly population and presents a high burden to society. Osteoporotic fractures may occur after a minimal trauma of the vertebrae. Electrical automated massage chair (EAMC) is a device that uses a programmed algorithm to perform automated massage. The massage chair, a popular device among elderly with back pain, relies on friction and rhythmic tapping created by a motorized roller. However, research regarding the safety of this device is lacking, especially in the perspective of OVCF. We present a case of an elderly woman diagnosed with acute OVCF of the thoracic spine after using an EAMC. The patient had no risk factor for fragility fracture and experienced an abrupt onset of severe upper back pain while using EAMC. Imaging studies revealed an isolated acute compression fracture at T8 vertebra (AO classification type A1) while dual-energy X-Ray absorptiometry scan confirmed osteoporosis. The patient was treated with a plastic orthosis and oral medications for osteoporosis. After 6-months follow-up, the patient showed union of the fractured T8 vertebra and no remaining symptoms. This case highlights that OVCF can be induced by EAMC. Therefore, patients with or at risk for osteoporosis should be cautious while opting for deep tissue massage using EAMC.


Asunto(s)
Fracturas por Compresión/etiología , Masaje/efectos adversos , Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/etiología , Anciano , Femenino , Fracturas por Compresión/diagnóstico por imagen , Humanos , Masaje/instrumentación , Fracturas Osteoporóticas/diagnóstico por imagen , Radiografía , Fracturas de la Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones
7.
Phys Rev Lett ; 120(13): 136402, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694193

RESUMEN

Strong charge-spin coupling is found in a layered transition-metal trichalcogenide NiPS_{3}, a van der Waals antiferromagnet, from studies of the electronic structure using several experimental and theoretical tools: spectroscopic ellipsometry, x-ray absorption, photoemission spectroscopy, and density functional calculations. NiPS_{3} displays an anomalous shift in the optical spectral weight at the magnetic ordering temperature, reflecting strong coupling between the electronic and magnetic structures. X-ray absorption, photoemission, and optical spectra support a self-doped ground state in NiPS_{3}. Our work demonstrates that layered transition-metal trichalcogenide magnets are useful candidates for the study of correlated-electron physics in two-dimensional magnetic materials.

8.
Clin Radiol ; 73(4): 412.e9-412.e16, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29203094

RESUMEN

AIM: To compare the clinical effectiveness of percutaneous stent placement between T and criss-cross configuration techniques in patients with advanced malignant hilar biliary obstruction. MATERIALS AND METHODS: Between January 2009 and December 2014, 59 patients who underwent percutaneous stent placement for malignant hilar obstruction were included in this retrospective study. T-configured stent placement (T group) was performed in 33 patients and criss-cross configured stent placement (criss-cross group) in 26 patients. Technical and clinical success, complications, patient survival, and stent patency were compared between the two groups. RESULTS: Stent placement was technically successful in all patients of the two groups. Clinical success was achieved in 30 (90.9%) patients of T group and 25 (96.9%) of criss-cross group (p=0.62). Two patients in the T group (6.1%) required additional stent placement for internal drainage of undrained sector. There were no major complications. Median survival was not statistically different between the two groups (128 days in the T group versus 183 days in the criss-cross group; p=0.33). Stent occlusion occurred in 15 patients in the T group and seven patients in the criss-cross group. The stent patency of the criss-cross group (median 330 days) was longer than that of the T group (median 132 days; p=0.0007). CONCLUSIONS: Early clinical effectiveness is comparable between the two techniques; however, additional intervention is occasionally required for drainage of an undrained sector after T-configured stent placement. Stent placement with criss-cross configuration provides longer stent patency than T-configuration technique.


Asunto(s)
Neoplasias de los Conductos Biliares/complicaciones , Colestasis/etiología , Colestasis/terapia , Tumor de Klatskin/complicaciones , Cuidados Paliativos/métodos , Stents , Anciano , Conductos Biliares/diagnóstico por imagen , Pancreatocolangiografía por Resonancia Magnética , Colestasis/diagnóstico por imagen , Drenaje/métodos , Femenino , Humanos , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
J Eur Acad Dermatol Venereol ; 31(12): 1999-2009, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28681405

RESUMEN

Psoriasis can be a socially isolating disease due to debilitating physical symptoms and the stigma patients feel because of the appearance of their skin. Mental health comorbidities such as anxiety, depression and suicidal ideation and behaviour (SIB) are prevalent in patients with psoriasis. Patients with mild psoriasis can experience psychiatric comorbidities; however, disorders such as depression and SIB are more common in patients with severe psoriasis or psoriatic arthritis. Psychiatric disorders can both result from and contribute to progression of psoriasis, suggesting that psoriasis and psychiatric conditions, such as depression, may have overlapping biological mechanisms. Proinflammatory cytokines such as interleukin (IL)-1 and IL-6 are elevated in both psoriasis and depression, indicating that the inflammatory process may be involved in the progression of both diseases. Elevated cytokine levels in the central nervous system cause physiologic and biochemical changes that may contribute to the development of depression. In this review of the literature, we discuss the evidence that supports the association of psoriasis with mental health disorders and the tools used to detect the presence of these comorbidities. Additionally, we review the most prominent hypotheses on the mechanisms by which the inflammatory response and elevated cytokines can cause depression. These results highlight the role that systemic inflammation plays in the various mental health comorbidities associated with psoriasis, including depression and SIB.


Asunto(s)
Citocinas/fisiología , Depresión/etiología , Psoriasis/complicaciones , Ideación Suicida , Suicidio , Humanos , Psoriasis/etiología
10.
Epidemiol Infect ; 142(3): 484-93, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23806331

RESUMEN

To assess the prevalence and risk factors for colonization with Staphylococcus aureus in inmates entering two maximum-security prisons in New York State, USA, inmates (N=830) were interviewed and anterior nares and oropharyngeal samples collected. Isolates were characterized using spa typing. Overall, 50·5% of women and 58·3% of men were colonized with S. aureus and 10·6% of women and 5·9% of men were colonized with MRSA at either or both body sites. Of MSSA isolates, the major subtypes were spa type 008 and 002. Overall, risk factors for S. aureus colonization varied by gender and were only found in women and included younger age, fair/poor self-reported general health, and longer length of prior incarceration. Prevalence of MRSA colonization was 8·2%, nearly 10 times greater than in the general population. Control of epidemic S. aureus in prisons should consider the constant introduction of strains by new inmates.


Asunto(s)
Prisioneros , Infecciones Estafilocócicas/epidemiología , Adolescente , Adulto , Factores de Edad , Femenino , Estado de Salud , Humanos , Masculino , New York/epidemiología , Prevalencia , Factores de Riesgo , Factores Sexuales , Staphylococcus aureus/aislamiento & purificación , Encuestas y Cuestionarios
11.
Asian-Australas J Anim Sci ; 26(2): 266-74, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25049786

RESUMEN

The effect of different phytogenic feed additives on reducing odorous compounds in swine was investigated using in vitro fermentation and analyzed their microbial communities. Soybean meal (1%) added with 0.1% different phytogenic feed additives (FA) were in vitro fermented using swine fecal slurries and anaerobically incubated for 12 and 24 h. The phytogenic FAs used were red ginseng barn powder (Panax ginseng C. A. Meyer, FA1), persimmon leaf powder (Diospyros virginiana L., FA2), ginkgo leaf powder (Ginkgo biloba L., FA3), and oregano lippia seed oil extract (Lippia graveolens Kunth, OL, FA4). Total gas production, pH, ammonia-nitrogen (NH3-N), hydrogen sulfide (H2S), nitrite-nitrogen (NO2 (-)-N), nitrate-nitrogen (NO3 (-)-N), sulfate (SO4 (--)), volatile fatty acids (VFA) and other metabolites concentration were determined. Microbial communities were also analyzed using 16S rRNA DGGE. Results showed that the pH values on all treatments increased as incubation time became longer except for FA4 where it decreased. Moreover, FA4 incubated for 12 and 24 h was not detected in NH3-N and H2S. Addition of FAs decreased (p<0.05) propionate production but increased (p<0.05) the total VFA production. Ten 16S rRNA DGGE bands were identified which ranged from 96 to 100% identity which were mostly isolated from the intestine. Similarity index showed three clearly different clusters: I (FA2 and FA3), II (Con and FA1), and III (FA4). Dominant bands which were identified closest to Eubacterium limosum (ATCC 8486T), Uncultured bacterium clone PF6641 and Streptococcus lutetiensis (CIP 106849T) were present only in the FA4 treatment group and were not found in other groups. FA4 had a different bacterial diversity compared to control and other treatments and thus explains having lowest odorous compounds. Addition of FA4 to an enriched protein feed source for growing swine may effectively reduce odorous compounds which are typically associated with swine production.

12.
Asian-Australas J Anim Sci ; 25(2): 213-23, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25049554

RESUMEN

In this study, two experiments were conducted to evaluate the total mixed ration with fermented feed (TMRF) and total mixed ration (TMR) by rumen in vitro fermentation and their effects on the growth performance and blood characteristics of Hanwoo steers. In experiment 1, three Hanwoo steers (600±47 kg), each permanently fitted with a ruminal cannula were used. In this experiment, three diets designated as T1, TMRF (18.4% fermented feed, tall fescue, mammoth wild rye forage and whole crop barley); T2, TMRF (17.7% fermented feed, rice straw and whole crop barley); and T3, TMR (rice straw, whole crop barley and probiotics, but no fermented feed), which were subjected to rumen in vitro fermentation for 48 h. The results demonstrated that DM disappearance rate gradually increased with advancing fermentation time, but T1 and T2 were higher than the T3 (p<0.05) from 3 h to 12 h, but insignificant (p>0.05) at 24 and 48 h. None of the specific VFAs were affected except for acetic and non volatile lactic acids, which were produced more in T2 than in T1 and T3 at 24 h and 48 h of incubation. A/P was lower in T1 and T2 than inT3 at 24 h (p<0.05) and 48 h (p>0.05) of incubation. These results confirmed that TMRF-related treatment shows a superior performance to that of TMR during the ruminal fermentation period. In experiment 2, the three diets in experiment 1 plus 1 more control diet (concentrates, probiotics and 2% rice straw of body weight) were fed to the 48 Hanwoo steers (160±10 kg) for a period of 168 d. The results demonstrated that the daily and total live weight gain and feed efficiency were higher (p<0.05) in the TMRF and TMR groups than in the control group. SGOT, SGPT and BUN (p<0.05) were reduced in TMRF relative to the control and TMR groups by 168 d which confirmed that TMRF shows better blood profiles than the TMR and control groups. Overall, these results appear to show that TMRF has better in vitro ruminal characteristics than those of TMR; growth performance and blood profiles were also found to be superior in TMRF than in the TMR and control groups. Thus, our findings suggest that TMRF-based feed supplies are favorable for Hanwoo cattle.

13.
Asian-Australas J Anim Sci ; 25(5): 690-700, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-25049615

RESUMEN

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen (NH3-N) and H2S gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, NH3-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as NO2, NO3 and SO4 concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that NH3-N, H2S and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

14.
Arch Virol ; 156(6): 1025-30, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21340742

RESUMEN

It is important to investigate the prevalence of salmonid pathogens because they can affect the amount of release of salmonid fry and the migration rate of adult salmonids. In this study, routine surveys were conducted for investigating virus distribution in migrating chum salmon spawners (Oncorhynchus keta) and their offsprings at the Namdae River, Yangyang, Korea, during 2006-2008. Anterior kidneys were removed from chum salmon spawner individuals, homogenized with minimal essential medium, and centrifuged to make supernatants for conducting RT-PCR. Five offspring were pooled to for conducting RT-PCR. Infectious pancreatic necrosis virus (IPNV), infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicemia virus (VHSV) were the target viruses for monitoring. In 2006, only spawners were investigated, and 27.5% of fish (22/80) were found to be IHNV-positive by nested PCR. In 2007, 65.6% of pooled fry (21/32) were IHNV-positive, and 9.4% (3/32) were IPNV-positive by one-step PCR. When nested PCR was conducted, 84.4% (27/32) were IHNV-positive, and 28.1% (9/32) were IPNV-positive. However, only 1.3% of spawners (1/80) were IHNV-positive by nested PCR. In 2008, 25% (8/32) of pooled fry were IHNV-positive by one-step PCR, but 59.4% (19/32) were IHNV-positive and 12.5% (4/32) were IPNV-positive by nested PCR. All of the samples tested were VHSV-negative. Although all viruses detected in this study were from chum salmon, phylogenetic analysis showed that they possibly originated from rainbow trout or clustered with the rainbow trout isolates. More extensive long-term studies are needed to clarify the origins of these viruses and their potential effects on chum salmon migration in Korea.


Asunto(s)
Migración Animal , Virus de la Necrosis Pancreática Infecciosa/aislamiento & purificación , Novirhabdovirus/aislamiento & purificación , Oncorhynchus keta/virología , Animales , Riñón/virología , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , República de Corea
15.
J Phys Chem A ; 115(47): 13804-10, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22013917

RESUMEN

Remote sensing of CO(2) requires high-fidelity reference data of spectral line parameters to be successful. The 6360 cm(-1) region is commonly used by satellites, field campaigns, and point-source gas sensors because it contains well-characterized and relatively isolated transitions of appropriate line strengths for atmospheric applications. However, the presence of gases other than CO(2), N(2), and O(2) can be a source of uncertainty for atmospheric measurements. Near 6360 cm(-1), there are numerous H(2)O and HDO transitions. Water makes up approximately 1-4% of Earth's lower atmosphere and can interfere with remote sensing measurements by (1) appearing as a direct spectral interference or (2) acting as a foreign broadener for CO(2) lines. The primary goal of this work was to quantify H(2)O broadening of CO(2) through precision spectroscopy measurements on the R16e transition at 6359.967 cm(-1) and its two nearest neighbors. A secondary goal was to assess the accuracy of H(2)O reference line parameters in the HITRAN 2008 database for spectrally removing typical levels of moisture from air samples containing approximately 400 ppm of CO(2).


Asunto(s)
Dióxido de Carbono/química , Agua/química , Espectroscopía Infrarroja Corta
16.
J Nanosci Nanotechnol ; 11(5): 4328-32, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21780451

RESUMEN

In-situ synchrotron radiation photoemission spectroscopy and X-ray photoemission spectroscopy have been used to investigate the initial stages of Al2O3 growth on a Si(001) substrate by atomic layer deposition (ALD). The core level spectra of Si 2p, O 1s, and Al 2p as well as the valence band spectra were measured at every half reaction in the trimethylaluminum (TMA)-H2O ALD process. The line shape changes and binding energy shifts of the core level spectra reveal that Al2O3 is predominantly formed with a small amount of Si oxide in the initial stages without the formation of Al silicate. All core level spectra were alternately shifted toward higher and lower binding energies sides at every half ALD reaction. This can be explained by the band bending effect induced by different chemical species on the surface during the TMA-H2O ALD reaction. The valence band spectra showed that four cycles of ALD reactions were necessary to complete the electronic structure of the Al2O3 film with a valence band offset of 3.73 eV.

17.
Clin Exp Rheumatol ; 26(4): 646-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18799097

RESUMEN

OBJECTIVE: The presence of hypoxia in rheumatoid synovium has been well known, but exact correlation between hypoxia and synovitis is unclear. The aim of our study was to investigate the time and spatial relationship and the correlation of severity between hypoxia and synovitis in pre-arthritic or early stage of inflammatory joint disease. METHODS: DBA/1J mice were injected intradermally with type II collagen and adjuvant solution to induce arthritis; mice injected with only adjuvant were used as a control group. CIA and control mice were sacrificed weekly after the injection to evaluate serial pathological changes. H&E stain and hydroxyprobe-1 stain were performed to look at the status of inflammation and hypoxia. RESULTS: In serial observations of tissue pathology, we could note the inflammation of synovium developing a week after the injection of type II collagen. Hypoxic change, measured by the hydroxyprobe-1 stain, was also identified in synovium as early as 1 week after the collagen injection, prior to clinically evident arthritis. In addition, we could observe that inflammation and hypoxia co-localize in the synovium and there was a positive correlation between the severity of hypoxia and the degree of synovitis. CONCLUSION: Our results demonstrate that hypoxia takes place in synovium at the pre-arthritic stage of disease and have a close spatial relationship and a positive severity correlation with synovitis.


Asunto(s)
Artritis Reumatoide/fisiopatología , Hipoxia/fisiopatología , Sinovitis/fisiopatología , Animales , Artritis Experimental , Artritis Reumatoide/patología , Hipoxia/patología , Ratones , Sinovitis/patología
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(5 Pt 2): 056105, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18643134

RESUMEN

Weighted scale-free networks exhibit two types of degree-strength relationship: linear and nonlinear relationships between them. To understand the mechanism underlying such empirical relationships, theoretical evolution models for weighted scale-free networks have been introduced for each case. However, those models have not yet been tested with empirical data. In this study, we collect temporal records of several online bulletin board systems and a movie actor network. We measure the growth rates of degree and strength of each vertex and weight of each edge within the framework of preferential attachment (PA). We also measure the probability of creating new edges between unconnected pairs of vertices. Then, based on the measured rates, linear and nonlinear growth models are constructed. We find that indeed the dynamics of creating new edges and adding weight to existing edges in a nonlocal manner is essential to reproduce the nonlinear degree-strength relationship. We also find that the degree-driven PA rule is more appropriate to real systems rather than the strength-driven one used for the linear model.

19.
Sci Total Environ ; 402(1): 36-42, 2008 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-18502474

RESUMEN

BACKGROUND: Mercury is a global pollutant that affects neurodevelopment of children. OBJECTIVE: The objectives were to measure and evaluate mercury concentration of children and mothers, and its association with exposure. METHODS: A cross-sectional assessment was done using questionnaires and hair mercury were analysed by Cold Vapor Atomic Absorption Spectrometry in the National Institute for Minamata Disease in Japan. RESULTS: A total of 112 children and 111 mothers were included; mean age was 34 months and 32 years, respectively. 17.9% of children and 34.2% of mothers had concentrations greater than 1 parts per million (ppm) as reference level. Body weight at birth, feeding methods, maternal age, and maternal education level were significantly different in each group (p<.05). Mean maternal hair mercury level (0.91 ppm) was higher than children (0.74 ppm), and has a positive correlation between them (p<.05). 68.1% of children, 75% of pregnant period, 63.4% of lactating period, and 78.6% of last six months have been consuming fish. With multiple regression analysis, hair mercury levels in children aged less than 6 months had a linear relationship with body weight at birth, gestational weeks, feeding methods (breast- or bottle- feeding) and maternal educational level. While children aged over 6 months significantly differed with gender, frequency of fish servings per week, and frequency of maternal fish consumption in lactation period. And hair mercury levels had inverse linear relationship with maternal monthly income in this age group. Maternal mercury levels had linear relationship with maternal age. CONCLUSION: Mercury levels in children may be affected by their mothers due to similar dietary patterns. Further long-term large-scale and follow-up studies are needed.


Asunto(s)
Monitoreo del Ambiente , Productos Pesqueros , Cabello/efectos de los fármacos , Lactancia/efectos de los fármacos , Exposición Materna/efectos adversos , Mercurio , Contaminantes Químicos del Agua , Factores de Edad , Preescolar , Femenino , Productos Pesqueros/análisis , Productos Pesqueros/toxicidad , Contaminación de Alimentos , Cabello/química , Cabello/metabolismo , Humanos , Lactante , Corea (Geográfico) , Lactancia/metabolismo , Mercurio/análisis , Mercurio/metabolismo , Mercurio/toxicidad , Madres , Embarazo , Espectrofotometría Atómica , Encuestas y Cuestionarios , Factores de Tiempo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad
20.
Environ Technol ; 29(6): 633-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18702289

RESUMEN

This paper assesses the potential of magnetically modifiedzeolite (MMZ) for ammonia removal from aqueous solution. The effects of relevant parameters such as contact time, pH and initial ammonia concentration were examined. The results show that ammonium ion removal by MMZ occurs rapidly within the first five minutes, pH has an effect on ammonium ion removal efficiency, and the ammonium ion removal capacity of MMZ increases with increase in initial ammonium ion concentration. The Langmuir and Freundlich adsorption isotherms were used to determine the adsorption characteristics. Ammonium-laden MMZ seems to be regenerated completely by sodium chloride solution at pH 11-12.


Asunto(s)
Magnetismo , Compuestos de Amonio Cuaternario/química , Purificación del Agua/métodos , Agua/química , Zeolitas/química , Adsorción , Concentración de Iones de Hidrógeno , Compuestos de Amonio Cuaternario/aislamiento & purificación , Soluciones
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