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1.
Sci Rep ; 14(1): 2059, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267507

RESUMO

Perceptions of current stimuli are sometimes biased toward or away from past perceptions. This phenomenon is called serial dependence. However, the strength of the effect of past responses on serial dependence has not been fully elucidated. We conducted experiments with a task in which participants estimated the number of dot arrays (numerosity estimation task) and directly compared whether the strength of serial dependence changed in the numerosity estimation task when participants responded or did not respond in the immediately preceding trial. We also examined whether the strength of serial dependence affected the accuracy of the numerosity estimation. We found that attractive serial dependence was stronger when participants responded in the immediately preceding trial than when they only saw the stimulus. The results suggest that the information from the previous stimulus must reach the higher-level processes associated with perceptual decisions to influence the estimation of the current stimulus. However, it is possible that the results of this study are specific to tasks in which participants respond with numeric symbols. The magnitude of the serial dependence effect was not observed to affect numerosity estimation performance, and no evidence was found that serial dependence enhances accuracy in the numerosity estimation task.


Assuntos
Conceitos Matemáticos , Humanos
2.
Sci Rep ; 13(1): 18359, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884564

RESUMO

Phototherapy converts lipophilic unconjugated bilirubin to hydrophilic bilirubin photoisomers, such as lumirubin. We comparatively used a blue light-emitting diode (LED) and a green fluorescent lamp (FL) as light sources for phototherapy of hyperbilirubinemic preterm neonates with the aim of examining potential differences in urinary lumirubin excretion between these two wavelengths. Urinary lumirubin levels were measured using a fluorescence assay with blue light exposure in the presence of the unconjugated bilirubin-inducible fluorescent protein UnaG, and denoted as urinary UnaG-bound bilirubin (UUB)/creatinine (Cr) (µg/mg Cr). Preterm neonates born at ≤ 33 weeks gestational age and treated with phototherapy were subjected to this study. The maximum UUB/Cr level during phototherapy per device intensity was compared between neonates treated with the blue LED and the green FL. A total of 61 neonates were examined to determine the maximum UUB/Cr levels. The median of maximum UUB/Cr excretion per light intensity of each device (µg/mg Cr/µW/cm2/nm) was 0.83 for the blue LED and 1.29 for the green FL (p = 0.01). Green light was found to be more effective than blue one for bilirubin excretion via urinary lumirubin excretion. This is the first spectroscopic study to compare the efficacy of phototherapy at different wavelengths using fluorescence assay.


Assuntos
Icterícia Neonatal , Icterícia , Recém-Nascido , Humanos , Fototerapia/métodos , Icterícia Neonatal/terapia , Bilirrubina/metabolismo
3.
Sci Rep ; 12(1): 20212, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418459

RESUMO

Perceptions of current stimuli are sometimes biased toward or away from past perceptions. This phenomenon is called serial dependence. However, it remains unclear whether serial dependence originates from lower-order perceptual processing, higher-order perceptual processing or cognitive processing. We examined the effects of serial dependence when participants estimated the total number of coins or the monetary value of coins displayed and found attractive effects in both tasks. The attractive effect observed in the value estimation task suggests that serial dependence occurs through higher-order cognitive processes during calculation. We also examined the effect of response history (i.e., the responses of participants on previous trials), with multiple regression analyses that simultaneously evaluated the effects of the previous stimuli and responses. In both number and value estimation tasks, the immediately prior response had an attractive effect on current responses, while the immediately prior stimuli exerted a repulsive effect. This pattern suggests that the attractive serial dependence found in the single regression analysis was due to the correlation between stimulus and response in the previous trials and that the effect of past stimuli per se may be an adaptation that increases sensitivity to current stimuli.


Assuntos
Asco , Numismática , Humanos , Aclimatação , Processos Mentais , Registros
4.
Nanoscale Adv ; 4(17): 3573-3584, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36134343

RESUMO

Low-dimensional titanate nanostructures are gaining attention as a promising material for various photocatalytic applications. However, these conventional titanium oxide-based materials cannot utilize visible light because of their wide bandgap, and their synthesis generally requires high-alkali (10 mol L-1) and high-temperature (160-200 °C) conditions. Here, we report facile bottom-up synthesis for the visible light-activated peroxo-titanate nanoribbon (PTNR). The use of the peroxo-titanium complex ion containing the potassium ion as a precursor can induce the formation of a layered potassium titanate structure (K2-x H x Ti2O5) based on the self-organization reaction between titanium complex ions and potassium ions under mild synthetic conditions (0.29-4.39 mol L-1 KOH, 100 °C). Furthermore, the requirement of potassium ions in the formation of layered potassium titanate was stoichiometrically examined. The layered titanate crystals could be grown anisotropically, which depended on the radius of the cation used. Our results newly revealed that the larger radius of the interlayer cation promotes anisotropic crystal growth. As a result, in the case of the potassium base, a nanoribbon structure with a higher aspect ratio and larger specific surface area than those of lithium and sodium bases was formed. The formed peroxo-titanium functional groups significantly reduced the bandgap of titanate to 2.64 eV. In a photocatalytic decolorization test, the PTNR showed excellent photocatalytic performance based on the large surface area and enhanced light absorption in the visible light range while still performing well under UV light. These findings show not only that the proposed synthetic process has a low environmental impact but also that it contributes to the development of highly functionalized materials for photochemical applications.

5.
Sci Rep ; 12(1): 11798, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821401

RESUMO

Lumirubin is the most prevalently excreted hydrophilic bilirubin photoisomer in phototherapy for neonatal jaundice caused by excess hydrophobic unconjugated bilirubin (ZZ-bilirubin). We developed a simple method to estimate the amount of lumirubin by monitoring the reverse photoisomerization of lumirubin to ZZ-bilirubin. Although lumirubin formation was long considered irreversible, exposure to blue light in the presence of the fluorescent protein UnaG, which binds specifically and tightly to ZZ-bilirubin, enables the reverse photoisomerization of lumirubin. This reaction was first detected using a fluorescence assay of neonatal urine sampled during phototherapy and purified lumirubin. The phenomenon of reverse photoisomerization of lumirubin was validated using liquid chromatography-mass spectrometry, which confirmed that lumirubin is reconverted to ZZ-bilirubin in the presence of UnaG. Analyses of 20 urine samples from 17 neonates revealed a significant correlation (correlation coefficient [r] = 0.978; 95% confidence interval 0.867-0.979; P < .001) between lumirubin and ZZ-bilirubin concentration before and after reverse photoisomerization. In general, the rate of photo-reconversion of lumirubin to ZZ-bilirubin is approximately 40%. In conclusion, we demonstrate here that lumirubin can be photo-reconverted to ZZ-bilirubin via exposure to blue light in the presence of UnaG. Utilizing this approach, urinary lumirubin levels can be estimated using an easy-to-perform fluorescence assay.


Assuntos
Icterícia Neonatal , Bilirrubina/metabolismo , Humanos , Recém-Nascido , Icterícia Neonatal/terapia , Luz , Espectrometria de Massas , Fototerapia/métodos
6.
Mater Sci Eng C Mater Biol Appl ; 129: 112377, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34579896

RESUMO

The immunomodulatory antibacterial activity and osteoimmunomodulatory properties of implantable biomaterials significantly influence bone regeneration. Various types of ultraviolet (UV) instrument are currently in use to greatly enhance the antibacterial activity and osteoconductive capability of titanium, it remains unclear how UV treatment modulates immune response. Compared to traditional UV treatment, the combination of low-dose ozone with UV irradiation is considered a new option to give benefits to surface modification and reduce the drawbacks of UV and ozone individually. Herein, the aim of this study was to elucidate the immune-modulatory properties of macrophages on UV/ozone-irradiated titanium that serve as defense against S. aureus and the crosstalk between immune cells and osteoblasts. Three different cell and bacteria co-culture systems were developed in order to investigate the race between host cells and bacteria to occupy the surface. In vitro immunological experiments indicated that UV/ozone irradiation significantly enhanced the phagocytic and bactericidal activity of macrophages against S. aureus. Further, in vitro and in vivo studies evidenced the favorable osteoimmune environment for osteogenic differentiation and bone formation. This research suggests vital therapeutic potential of UV/ozone irradiation for preventing the biomaterial-associated infections and achieving favorable bone formation simultaneously.


Assuntos
Ozônio , Titânio , Antibacterianos/farmacologia , Regeneração Óssea , Imunidade , Osteogênese , Ozônio/farmacologia , Staphylococcus aureus , Propriedades de Superfície , Titânio/farmacologia
7.
Regen Ther ; 14: 344-351, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32490060

RESUMO

INTRODUCTION: The objective of this study was to evaluate the cell viability of layered cell sheets, irradiated with 222 nm UV light. METHODS: UV transmittance of 222 nm and 254 nm was evaluated when the cell sheets of NCTC Clone 929 cells were irradiated UV light. Cell viability was evaluated after irradiation of 222 nm using 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. Following irradiation of two layered cell sheets at 500 mJ/cm2, the cell damage of lower layers was evaluated by a colony formation and MTT assays. RESULTS: The UV transmittance of 222 nm was 10 times less than that of 254 nm. A MTT assay revealed that cells of cell sheets irradiated at 222 nm was less damaged than those at 254 nm, when irradiated at 5 mJ/cm2. Cell colonies were formed for cells of lower layers irradiated at 222 nm whereas no colony formation was observed for those irradiated at 254 nm. Significantly higher MTT activity was observed for cells of lower layers irradiated at 222 nm than at 254 nm. CONCLUSIONS: It is concluded that 222 nm irradiation is biologically safe for cell viability.

8.
J Hosp Infect ; 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32243946

RESUMO

BACKGROUND: UVC has been used to inactivate several pathogens. Unlike the conventional 254-nm UVC, 222-nm UVC is harmless to mammalian cells. AIM: To investigate the disinfection efficacy of 222-nm UVC against human pathogens which are commonly found in the environment and healthcare facilities. METHODOLOGY: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica subsp. serovar Typhimurium, Campylobacter jejuni, Bacillus cereus (vegetative cells and endospores), Clostridium sporogenes (vegetative cells and endospores), Clostoridioides difficile (endospores), Candida albicans (yeast), Aspergillus niger (hyphae and spores), Trichophyton rubrum (hyphae and spores), feline calicivirus and influenza A virus were irradiated with 222-nm UVC at various doses. The remaining live bacterial and fungal cells, and the viral infectivity were evaluated. The efficiency of 222-nm UVC germicidal effect was compared to that of the conventional 254-nm UVC. RESULTS: The 222-nm UVC showed potent germicidal effect to vegetative bacterial cells, yeast and viruses as efficient as the 245-nm UVC. The 222-nm UVC exhibited more potent germicidal effect to bacterial endospores, compared with the 254-nm UVC. The fungicidal effect of 222-nm UVC against the fungal spores and hyphae was weaker than that of 254-nm UVC. CONCLUSIONS: The 222-nm UVC is able to inactivate a wide spectrum of microbial pathogens. In comparison with the conventional 254-nm UVC, the germicidal effect of 222-nm UVC to the fungal hyphae and spores is low, but the 222-nm UVC exhibits strong germicidal effect to the bacterial endospores.

9.
BMC Musculoskelet Disord ; 20(1): 292, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31208382

RESUMO

BACKGROUND: Titanium instrumentations are widely used in orthopedics; the metal bonds with bone in a process called osseointegration. Over time, hydrocarbons adhere to the instrumentation, which weakens the bone-binding ability. Ultraviolet photofunctionalization enhances the bone-binding ability of instrumentation by reducing hydrocarbons. The process has been proven effective in dentistry, but its effects in orthopedics are unverified. We aimed to determine the effect of ultraviolet photofunctionalization of titanium instrumentation used in lumbar fusion. METHODS: This was a non-randomized controlled trial. We prospectively enrolled 13 patients who underwent lumbar fusion surgery. We inserted two pure titanium cages into each intervertebral space; one cage had undergone ultraviolet photofunctionalization, while the other was untreated. The degree of osteosclerosis around both cages was then compared by measuring the densities around the cages on imaging at 2, 3, 6, and 12 months postoperatively compared with 1 month postoperatively. The carbon attachment of the titanium cages was measured using X-ray photoelectron spectroscopy. RESULTS: There was no significant difference between the degree of osteosclerosis (as assessed by the density) around the treated versus untreated cages at any timepoint. The ratio of carbon attachment of the titanium cages was only 20%, which was markedly less than the ratio of carbon attachment to titanium instrumentation previously reported in the dentistry field. CONCLUSIONS: The effect of ultraviolet photofunctionalization of titanium instrumentation in spine surgery is questionable at present. The biological aging of the titanium may be affected by differences in the manufacturing process of orthopedics instrumentation versus dentistry instrumentation. TRIAL REGISTRATION: UMIN Clinical Trials Registry (Identifier: UMIN000014103 ; retrospectively registered on June 1, 2014).


Assuntos
Interface Osso-Implante/efeitos da radiação , Osseointegração/efeitos da radiação , Fusão Vertebral/instrumentação , Titânio/efeitos da radiação , Raios Ultravioleta , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Osteosclerose/diagnóstico por imagem , Osteosclerose/prevenção & controle , Estudos Prospectivos , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Titânio/efeitos adversos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
PLoS One ; 13(7): e0201259, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30044862

RESUMO

Surgical site infections (SSIs) represent an important clinical problem associated with increased levels of surgical morbidity and mortality. UVC irradiation during surgery has been considered to represent a possible strategy to prevent the development of SSI. 254-nm UVC induces marked levels of DNA damage by generating cyclobutyl pyrimidine dimers (CPD) in microorganisms. However, this effect is elicited not only in microorganisms, but also in human cells, and chronic exposure to 254-nm UVC has been established to represent a human health hazard. In contrast, despite short wavelength-UVC light, especially 222-nm UVC, having been demonstrated to elicit a bactericidal effect, single irradiation with a high dose of 222-nm UVC energy has been reported to not induce mutagenic or cytotoxic DNA lesions in mammalian cells. However, the effect of chronic irradiation with a high dose of 222-nm UVC to mammalian cells has not been determined. In this study, it was demonstrated that large numbers of CPD-expressing cells were induced in the epidermis of mice following treatment with a small amount of single exposure 254-nm UVC, and then less than half of these cells reduced within 24 h. Chronic 254-nm UVC irradiation was revealed to induce sunburn and desquamation in mouse skin. Histological analysis demonstrated that small numbers of CPD-expressing cells were detected only in hyperkeratotic stratum corneum after chronic irradiation with a high dose of 254-nm UVC, and that significant hyperplasia and intercellular edema were also induced in the epidermis of mice. In contrast, chronic irradiation with 222-nm UVC light was revealed not to induce mutagenic or cytotoxic effects in the epidermis of mice. These results indicated that 222-nm UVC light emitted from the lamp apparatus (or device), which was designed to attenuate harmful light present in wavelengths of more than 230 nm, represents a promising tool for the reduction of SSI incidence in patients and hospital staff.


Assuntos
Dano ao DNA/efeitos da radiação , Epiderme/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , DNA/genética , Relação Dose-Resposta à Radiação , Epiderme/patologia , Feminino , Camundongos , Camundongos Pelados , Dímeros de Pirimidina/genética , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/radioterapia
12.
J Photochem Photobiol B ; 178: 10-18, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29101868

RESUMO

UVC radiation is known to be highly germicidal. However, exposure to 254-nm-UVC light causes DNA lesions such as cyclobutane pyrimidine dimers (CPD) in human cells, and can induce skin cancer after long-term repeated exposures. It has been reported that short wavelength UVC is absorbed by proteins in the membrane and cytosol, and fails to reach the nucleus of human cells. Hence, irradiation with 222-nm UVC might be an optimum combination of effective disinfection and biological safety to human cells. In this study, the biological effectiveness of 222-nm UVC was investigated using a mouse model of a skin wound infected with methicillin-resistant Staphylococcus aureus (MRSA). Irradiation with 222-nm UVC significantly reduced bacterial numbers on the skin surface compared with non-irradiated skin. Bacterial counts in wounds evaluated on days 3, 5, 8 and 12 after irradiation demonstrated that the bactericidal effect of 222-nm UVC was equal to or more effective than 254-nm UVC. Histological analysis revealed that migration of keratinocytes which is essential for the wound healing process was impaired in wounds irradiated with 254-nm UVC, but was unaffected in 222-nm UVC irradiated wounds. No CPD-expressing cells were detected in either epidermis or dermis of wounds irradiated with 222-nm UVC, whereas CPD-expressing cells were found in both epidermis and dermis irradiation with 254-nm UVC. These results suggest that 222-nm UVC light may be a safe and effective way to reduce the rate of surgical site and other wound infections.


Assuntos
Desinfecção/métodos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Infecções Estafilocócicas/terapia , Raios Ultravioleta , Cicatrização/efeitos da radiação , Animais , Dano ao DNA , Camundongos , Camundongos Endogâmicos BALB C , Pele/microbiologia , Pele/fisiopatologia , Pele/efeitos da radiação , Infecções Estafilocócicas/fisiopatologia
13.
Early Hum Dev ; 91(7): 381-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25984653

RESUMO

OBJECTIVE: Phototherapy using blue light-emitting diodes (LED) is effective against neonatal jaundice. However, green light phototherapy also reduces unconjugated jaundice. We aimed to determine whether mixed blue and green light can relieve jaundice with minimal oxidative stress as effectively as either blue or green light alone in a rat model. METHODS: Gunn rats were exposed to phototherapy with blue (420-520 nm), filtered blue (FB; 440-520 nm without<440-nm wavelengths, FB50 (half the irradiance of filtered blue), mixed (filtered 50% blue and 50% green), and green (490-590 nm) LED irradiation for 24h. The effects of phototherapy are expressed as ratios of serum total (TB) and unbound (UB) bilirubin before and after exposure to each LED. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured by HPLC before and after exposure to each LED to determine photo-oxidative stress. RESULTS: Values < 1.00 indicate effective phototherapy. The ratios of TB and UB were decreased to 0.85, 0.89, 1.07, 0.90, and 1.04, and 0.85, 0.94, 0.93, 0.89, and 1.09 after exposure to blue, filtered blue, FB50, and filtered blue mixed with green LED, respectively. In contrast, urinary 8-OHdG increased to 2.03, 1.25, 0.96, 1.36, 1.31, and 1.23 after exposure to blue, filtered blue, FB50, mixed, green LED, and control, indicating side-effects (> 1.00), respectively. CONCLUSIONS: Blue plus green phototherapy is as effective as blue phototherapy and it attenuates irradiation-induced oxidative stress. PRACTICE IMPLICATIONS: Combined blue and green spectra might be effective against neonatal hyperbilirubinemia.


Assuntos
Bilirrubina/sangue , Icterícia/terapia , Estresse Oxidativo/fisiologia , Fototerapia/métodos , 8-Hidroxi-2'-Desoxiguanosina , Animais , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Modelos Animais de Doenças , Humanos , Icterícia/sangue , Icterícia/urina , Masculino , Ratos , Ratos Gunn , Resultado do Tratamento
14.
Zoolog Sci ; 30(5): 386-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23646944

RESUMO

In Japan, rice paddies have acted as substitute habitats for pond-breeding frogs. However, frog populations are declining due to the loss of habitat and environmental changes in rice paddy areas. Frogs need both aquatic and terrestrial habitats to complete their life history; in rice paddy areas, levees that surround rice paddies provide terrestrial habitats for basking, foraging, and shelter from predators. Studying microhabitat use at levees is important to elucidating the ecological roles of levees and to properly managing them to support frog populations. In this study, we conducted surveys in lowland modernized rice paddy areas in Shiga Prefecture in which a common species, Hyla japonica, and an endangered species, Pelophylax porosa brevipoda, were found. We captured frogs at levees and recorded environmental factors related to levee vegetation, rice paddy conditions, and weather. We constructed generalized linear mixed models to examine the effects of environmental factors on juvenile and adult H. japonica and on small and large juveniles, females, and males of P. p. brevipoda. Our results showed distinct microhabitat uses at levees in different species, sexes, and body sizes. In general, abundance was high at levees with vegetation that provided shelter. The water depth in rice paddies negatively influenced juvenile H. japonica and large juvenile and small female P. p. brevipoda, and positively influenced small male P. p. brevipoda. The maintenance of a mosaic structure of levees was important not only to support frog populations but also to maintain frog diversity in the area.


Assuntos
Agricultura , Ecossistema , Ranidae/fisiologia , Animais , Feminino , Japão , Masculino
15.
Explore (NY) ; 9(2): 87-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23452710

RESUMO

BACKGROUND: Psycho-oncological care, including spiritual care, is essential for cancer patients. Integrated medicine, a therapy combining modern western medicine with various kinds of complementary and alternative medicine, can be appropriate for the spiritual care of cancer because of the multidimensional characteristics of the spirituality. In particular, therapies that enable patients to establish a deeper contact with nature, inspire feelings of life and growth of plants, and involve meditation may be useful for spiritual care as well as related aspects such as emotion. The purpose of the present study was to examine the effect of spiritual care of cancer patients by integrated medicine in a green environment. METHODS: The present study involved 22 cancer patients. Integrated medicine consisted of forest therapy, horticultural therapy, yoga meditation, and support group therapy, and sessions were conducted once a week for 12 weeks. The spirituality (the Functional Assessment of Chronic Illness Therapy-Spiritual well-being), quality of life (Short Form-36 Health Survey Questionnaire), fatigue (Cancer Fatigue Scale), psychological state (Profile of Mood States, short form, and State-Trait Anxiety Inventory) and natural killer cell activity were assessed before and after intervention. RESULTS: In Functional Assessment of Chronic Illness Therapy-Spiritual well-being, there were significant differences in functional well-being and spiritual well-being pre- and postintervention. This program improved quality of life and reduced cancer-associated fatigue. Furthermore, some aspects of psychological state were improved and natural killer cell activity was increased. CONCLUSIONS: It is indicated that integrated medicine performed in a green environment is potentially useful for the emotional and spiritual well-being of cancer patients.


Assuntos
Terapias Complementares , Meio Ambiente , Fadiga/prevenção & controle , Células Matadoras Naturais/metabolismo , Natureza , Neoplasias/terapia , Espiritualidade , Idoso , Doença Crônica , Emoções , Fadiga/etiologia , Feminino , Jardinagem , Humanos , Medicina Integrativa , Masculino , Meditação , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/imunologia , Neoplasias/psicologia , Cuidados Paliativos/métodos , Projetos Piloto , Psicoterapia de Grupo , Qualidade de Vida , Apoio Social , Árvores , População Urbana , Yoga
16.
Environ Monit Assess ; 185(5): 4117-24, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22972316

RESUMO

Drought-induced anomalies in vegetation condition over wide areas can be observed by using time-series satellite remote sensing data. Previous methods to assess the anomalies may include limitations in considering (1) the seasonality in terms of each vegetation-cover type, (2) cumulative damage during the drought event, and (3) the application to various types of land cover. This study proposed an improved methodology to assess drought impact from the annual vegetation responses, and discussed the result in terms of diverse landscape mosaics in the Mt. Kenya region (0.4° N 35.8° E ~ 1.6° S 38.4° E). From the 30-year annual rainfall records at the six meteorological stations in the study area, we identified 2000 as the drought year and 2001, 2004, and 2007 as the normal precipitation years. The time-series profiles of vegetation condition in the drought and normal precipitation years were obtained from the values of Enhanced Vegetation Index (EVI; Huete et al. 2002), which were acquired from Terra MODIS remote sensing dataset (MOD13Q1) taken every 16 days at the scale of 250-m spatial resolution. The drought impact was determined by integrating the annual differences in EVI profiles between drought and normal conditions, per pixel based on nearly same day of year. As a result, we successfully described the distribution of landscape vulnerability to drought, considering the seasonality of each vegetation-cover type at every MODIS pixel. This result will contribute to the large-scale landscape management of Mt. Kenya region. Future study should improve this method by considering land-use change occurred during the long-term monitoring period.


Assuntos
Secas , Plantas , Astronave , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Quênia , Tecnologia de Sensoriamento Remoto , Estações do Ano
17.
Zoolog Sci ; 29(9): 577-84, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22943781

RESUMO

In Japan, rice paddies play an important role as a substitute habitat for wetland species, and support rich indigenous ecosystems. However, since the 1950s, agricultural modernization has altered the rice paddy environment, and many previously common species are now endangered. It is urgently necessary to evaluate rice paddies as habitats for conservation. Among the species living in rice paddies, frogs are representative and are good indicator species, so we focused on frog species and analyzed the influence of environmental factors on their habitat use. We found four frog species and one subspecies (Hyla japonica, Pelophylax nigromaculatus, Glandirana rugosa, Lithobates catesbeianus, and Pelophylax porosa brevipoda) at our study sites in Shiga prefecture. For all but L. catesbeianus, we analyzed the influence of environmental factors related to rice paddy structure, water management and availability, agrochemical use, connectivity, and land use on breeding and non-breeding habitat use. We constructed generalized additive mixed models with survey date as the smooth term and applied Akaike's information criterion to choose the bestranked model. Because life histories and biological characteristics vary among species, the factors affecting habitat use by frogs are also expected to differ by species. We found that both breeding and non-breeding habitat uses of each studied species were influenced by different combinations of environmental factors and that in most cases, habitat use showed seasonality. For frog conservation in rice paddies, we need to choose favorable rice paddy in relation to surrounding land use and apply suitable management for target species.


Assuntos
Anuros/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Agricultura , Animais , Atividades Humanas , Japão
18.
Zoolog Sci ; 29(9): 599-603, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22943784

RESUMO

In Japan, rice paddies have acted as a substitute habitat for pond-breeding frogs. However, since the 1950s, agricultural modernization has altered the rice paddy environment, and pond-breeding frog populations have been decreasing. This agricultural modernization has led to rice paddy fragmentation via roadways and the construction of deep channels. To assess the influences of habitat fragmentation, we compared the distribution of two pond-breeding frogs, a common species, Hyla japonica, and an endangered species, Pelophylax porosa brevipoda, around a deep roadside ditch. In Shiga prefecture, we selected two rice paddies along a roadway and recorded the number of frogs and their snout-vent length (SVL) at the levee of a rice paddy, ditch, bank, and adjacent roadway. In total, we identified 1,293 P. p. brevipoda and 181 H. japonica. Most P. p. brevipoda were either at the levee or ditch, and the number of this species found in the ditch was much higher than in any other location in July and October. The SVLs of P. p. brevipoda found in the ditch in June were smaller than those in October. Most H. japonica were at the levee or bank, and there were no apparent temporal or spatial patterns of distribution. Our results suggest that the ditch acts as a barrier to juveniles in early summer and to all frogs during autumn for P. p. brevipoda but not for H. japonica. For long-term conservation, it is important to study the movement patterns related to life history and rice paddy management.


Assuntos
Agricultura/métodos , Migração Animal/fisiologia , Anuros/fisiologia , Animais , Demografia , Japão , Especificidade da Espécie
19.
Am J Bot ; 98(8): e233-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21821589

RESUMO

PREMISE OF THE STUDY: Microsatellite markers were developed to investigate genetic diversity and genetic structure of Euryale ferox, a vulnerable aquatic plant. METHODS AND RESULTS: Ten microsatellite loci were isolated and characterized for this species. Eight loci showed polymorphisms with two or three alleles per locus. As for the polymorphic markers, the expected and observed heterozygosities ranged from 0.00 to 0.08 and 0.17 to 0.64, respectively. CONCLUSIONS: The 10 microsatellite markers described here will be useful for investigating genetic diversity, genetic structure, and gene flow between populations of E. ferox.


Assuntos
DNA de Plantas/análise , Espécies em Perigo de Extinção , Genoma de Planta , Repetições de Microssatélites , Nymphaeaceae/genética , Alelos , Clonagem Molecular , DNA de Plantas/genética , Fluxo Gênico , Frequência do Gene , Biblioteca Gênica , Triagem de Portadores Genéticos/métodos , Heterozigoto , Japão , Nymphaeaceae/metabolismo , Folhas de Planta/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Polimorfismo Genético , Análise de Sequência de DNA , Especificidade da Espécie
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