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1.
Nanotechnology ; 32(14): 145603, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33339016

RESUMO

SnO2 nanofibers with uniform diameters were obtained by wet spinning using ordered anodic porous alumina as a spinneret, followed by heat treatment. Ordered alumina through-hole membrane is a suitable spinneret material for nanofiber spinning owing to its nanohole array structure with uniform-sizes holes. A polymer solution containing a Sn salt was used as a precursor solution for the wet spinning. Polymer nanofibers containing the Sn salt were continuously formed as the precursor passed through the alumina holes into a coagulating solution. Monodisperse nanofiber structures were successfully maintained, even after heat treatment at 600 °C. This process enabled the preparation of monodisperse SnO2 nanofibers with diameters below 100 nm, as well as the precise control of fiber diameter by changing the hole size of the porous alumina spinneret. The obtained SnO2 nanofibers will be useful in various functional devices.

2.
Opt Express ; 26(21): 27865-27872, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469844

RESUMO

An efficient preparation process for Al hole array structures emitting wavelength-selective thermal radiation that is based on the anisotropic anodic etching of Al was demonstrated. The formation of an ordered hole array was achieved by a masking process prior to the anodic etching. The present process allows the preparation of large samples because the masking of the Al foil has a high throughput owing to the simple printing process using a flexible stamp. The thermal radiation properties of the Al hole array could be controlled by adjusting the depth and aperture size of the holes.

3.
Mol Ecol ; 26(19): 5074-5085, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28749031

RESUMO

Elucidating the physiological mechanisms of the irregular yet concerted flowering rhythm of mass flowering tree species in the tropics requires long-term monitoring of flowering phenology, exogenous and endogenous environmental factors, as well as identifying interactions and dependencies among these factors. To investigate the proximate factors for floral initiation of mast seeding trees in the tropics, we monitored the expression dynamics of two key flowering genes, meteorological conditions and endogenous resources over two flowering events of Shorea curtisii and Shorea leprosula in the Malay Peninsula. Comparisons of expression dynamics of genes studied indicated functional conservation of FLOWERING LOCUS T (FT) and LEAFY (LFY) in Shorea. The genes were highly expressed at least 1 month before anthesis for both species. A mathematical model considering the synergistic effect of cool temperature and drought on activation of the flowering gene was successful in predicting the observed gene expression patterns. Requirement of both cool temperature and drought for floral transition suggested by the model implies that flowering phenologies of these species are sensitive to climate change. Our molecular phenology approach in the tropics sheds light on the conserved role of flowering genes in plants inhabiting different climate zones and can be widely applied to dissect the flowering processes in other plant species.


Assuntos
Dipterocarpaceae/genética , Flores/fisiologia , Proteínas de Plantas/genética , Mudança Climática , Dipterocarpaceae/fisiologia , Secas , Flores/genética , Florestas , Regulação da Expressão Gênica de Plantas , Malásia , Modelos Teóricos , Temperatura , Fatores de Transcrição/genética
4.
Am J Bot ; 103(11): 1912-1920, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27797714

RESUMO

PREMISE OF THE STUDY: In tropical rainforests of Southeast Asia, a highly fecund thrips (Thrips spp.) responds rapidly to the mass flowering at multiple-year intervals characteristic of certain species such as the canopy tree studied here, Shorea acuminata, by feeding on flower resources. However, past DNA analyses of pollen adherent to thrips bodies revealed that the thrips promoted a very high level of self-pollination. Here, we identified the pollinator that contributes to cross-pollination and discuss ways that the pollination system has adapted to mass flowering. METHODS: By comparing the patterns of floral visitation and levels of genetic diversity in adherent pollen loads among floral visitors, we evaluated the contribution of each flower visitor to pollination. KEY RESULTS: The big-eyed bug, Geocoris sp., a major thrips predator, was an inadvertent pollinator, and importantly contributed to cross-pollination. The total outcross pollen adhering to thrips was approximately 30% that on the big-eyed bugs. Similarly, 63% of alleles examined in S. acuminata seeds and seedlings occurred in pollen adhering to big-eyed bugs; about 30% was shared with pollen from thrips. CONCLUSIONS: During mass flowering, big-eyed bugs likely travel among flowering S. acuminata trees, attracted by the abundant thrips. Floral visitation patterns of big-eyed bugs vs. other insects suggest that these bugs can maintain their population size between flowering by preying upon another thrips (Haplothrips sp.) that inhabits stipules of S. acuminata throughout the year and quickly respond to mass flowering. Thus, thrips and big-eyed bugs are essential components in the pollination of S. acuminata.


Assuntos
Dipterocarpaceae/fisiologia , Polinização , Tisanópteros/fisiologia , Animais , Dipterocarpaceae/genética , Dipterocarpaceae/parasitologia , Flores/genética , Flores/parasitologia , Flores/fisiologia , Variação Genética , Técnicas de Genotipagem , Repetições de Microssatélites/genética , Pólen/genética , Pólen/parasitologia , Pólen/fisiologia , Densidade Demográfica , Floresta Úmida , Reprodução , Plântula/genética , Plântula/parasitologia , Plântula/fisiologia , Sementes/genética , Sementes/fisiologia , Árvores
6.
J Imaging ; 10(4)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38667986

RESUMO

A gait is a walking pattern that can help identify a person. Recently, gait analysis employed a vision-based pose estimation for further feature extraction. This research aims to identify a person by analyzing their walking pattern. Moreover, the authors intend to expand gait analysis for other tasks, e.g., the analysis of clinical, psychological, and emotional tasks. The vision-based human pose estimation method is used in this study to extract the joint angles and rank correlation between them. We deploy the multi-view gait databases for the experiment, i.e., CASIA-B and OUMVLP-Pose. The features are separated into three parts, i.e., whole, upper, and lower body features, to study the effect of the human body part features on an analysis of the gait. For person identity matching, a minimum Dynamic Time Warping (DTW) distance is determined. Additionally, we apply a majority voting algorithm to integrate the separated matching results from multiple cameras to enhance accuracy, and it improved up to approximately 30% compared to matching without majority voting.

7.
Mol Ecol ; 22(8): 2264-79, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23432376

RESUMO

Tropical rainforests in South-East Asia have been affected by climatic fluctuations during past glacial eras. To examine how the accompanying changes in land areas and temperature have affected the genetic properties of rainforest trees in the region, we investigated the phylogeographic patterns of a widespread dipterocarp species, Shorea leprosula. Two types of DNA markers were used: expressed sequence tag-based simple sequence repeats and chloroplast DNA (cpDNA) sequence variations. Both sets of markers revealed clear genetic differentiation between populations in Borneo and those in the Malay Peninsula and Sumatra (Malay/Sumatra). However, in the south-western part of Borneo, genetic admixture of the lineages was observed in the two marker types. Coalescent simulation based on cpDNA sequence variation suggested that the two lineages arose 0.28-0.09 million years before present and that following their divergence migration from Malay/Sumatra to Borneo strongly exceeded migration in the opposite direction. We conclude that the genetic structure of S. leprosula was largely formed during the middle Pleistocene and was subsequently modified by eastward migration across the subaerially exposed Sunda Shelf.


Assuntos
Dipterocarpaceae/genética , Evolução Molecular , Especiação Genética , Filogeografia , Bornéu , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Genética Populacional , Haplótipos , Indonésia , Malásia , Dados de Sequência Molecular , Análise de Sequência de DNA , Clima Tropical
8.
Sci Rep ; 13(1): 12408, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524745

RESUMO

I developed a simple crystal growth process to obtain a single Ga crystal. The crystal orientation of a Ga plate could be controlled by a crystal growth process using a seed Ga crystal. By anodizing a [100]-direction highly oriented Ga plate, I realized the formation of a highly ordered array of high-aspect-ratio straight nanoholes. It was observed that the nanohole growth direction depends on the crystal orientation of a Ga plate. To date, this dependence has yet to be observed in materials other than porous Ga oxide obtained by an anodization process. The present fabrication process is expected to be applied to the fabrication of various functional devices requiring a porous Ga oxide with high-aspect-ratio straight nanoholes, such as hydrogen formation devices and functional filters.

9.
Front Plant Sci ; 14: 1213496, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636106

RESUMO

Global warming-induced climate change causes significant agricultural problems by increasing the incidence of drought and flooding events. Waterlogging is an inevitable consequence of these changes but its effects on oil palms have received little attention and are poorly understood. Recent waterlogging studies have focused on oil palm seedlings, with particular emphasis on phenology. However, the transcriptomic waterlogging response of mature oil palms remains elusive in real environments. We therefore investigated transcriptomic changes over time in adult oil palms at plantations over a two-year period with pronounced seasonal variation in precipitation. A significant transcriptional waterlogging response was observed in the oil palm stem core but not in leaf samples when gene expression was correlated with cumulative precipitation over two-day periods. Pathways and processes upregulated or enriched in the stem core response included hypoxia, ethylene signaling, and carbon metabolism. Post-waterlogging recovery in oil palms was found to be associated with responses to heat stress and carotenoid biosynthesis. Nineteen transcription factors (TFs) potentially involved in the waterlogging response of mature oil palms were also identified. These data provide new insights into the transcriptomic responses of planted oil palms to waterlogging and offer valuable guidance on the sensitivity of oil palm plantations to future climate changes.

10.
PeerJ ; 11: e16368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047035

RESUMO

Climatic factors have commonly been attributed as the trigger of general flowering, a unique community-level mass flowering phenomenon involving most dipterocarp species that forms the foundation of Southeast Asian tropical rainforests. This intriguing flowering event is often succeeded by mast fruiting, which provides a temporary yet substantial burst of food resources for animals, particularly frugivores. However, the physiological mechanism that triggers general flowering, particularly in dipterocarp species, is not well understood largely due to its irregular and unpredictable occurrences in the tall and dense forests. To shed light on this mechanism, we employed ecological transcriptomic analyses on an RNA-seq dataset of a general flowering species, Shorea curtisii (Dipterocarpaceae), sequenced from leaves and buds collected at multiple vegetative and flowering phenological stages. We assembled 64,219 unigenes from the transcriptome of which 1,730 and 3,559 were differentially expressed in the leaf and the bud, respectively. Differentially expressed unigene clusters were found to be enriched with homologs of Arabidopsis thaliana genes associated with response to biotic and abiotic stresses, nutrient level, and hormonal treatments. When combined with rainfall data, our transcriptome data reveals that the trees were responding to a brief period of drought prior to the elevated expression of key floral promoters and followed by differential expression of unigenes that indicates physiological changes associated with the transition from vegetative to reproductive stages. Our study is timely for a representative general flowering dipterocarp species that occurs in forests that are under the constant threat of deforestation and climate change as it pinpoints important climate sensitive and flowering-related homologs and offers a glimpse into the cascade of gene expression before and after the onset of floral initiation.


Assuntos
Dipterocarpaceae , Transcriptoma , Animais , Transcriptoma/genética , Dipterocarpaceae/genética , Flores/genética , Perfilação da Expressão Gênica , Reprodução/genética
11.
Nanomaterials (Basel) ; 13(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37368324

RESUMO

Herein, we give an overview of several less explored structural and optical characterization techniques useful for biomaterials. New insights into the structure of natural fibers such as spider silk can be gained with minimal sample preparation. Electromagnetic radiation (EMR) over a broad range of wavelengths (from X-ray to THz) provides information of the structure of the material at correspondingly different length scales (nm-to-mm). When the sample features, such as the alignment of certain fibers, cannot be characterized optically, polarization analysis of the optical images can provide further information on feature alignment. The 3D complexity of biological samples necessitates that there be feature measurements and characterization over a large range of length scales. We discuss the issue of characterizing complex shapes by analysis of the link between the color and structure of spider scales and silk. For example, it is shown that the green-blue color of a spider scale is dominated by the chitin slab's Fabry-Pérot-type reflectivity rather than the surface nanostructure. The use of a chromaticity plot simplifies complex spectra and enables quantification of the apparent colors. All the experimental data presented herein are used to support the discussion on the structure-color link in the characterization of materials.

12.
Proc Biol Sci ; 279(1738): 2652-61, 2012 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-22398168

RESUMO

Livistona mariae is an endemic palm localized in arid central Australia. This species is separated by about 1000 km from its congener L. rigida, which grows distantly in the Roper River and Nicholson-Gregory River catchments in northern Australia. Such an isolated distribution of L. mariae has been assumed to have resulted from contraction of ancestral populations as Australia aridified from the Mid-Miocene (ca 15 Ma). To test this hypothesis at the population level, we examined the genetic relationships among 14 populations of L. mariae and L. rigida using eight nuclear microsatellite loci. Our population tree and Bayesian clustering revealed that these populations comprised two genetically distinct groups that did not correspond to the current classification at species rank, and L. mariae showed closest affinity with L. rigida from Roper River. Furthermore, coalescent divergence-time estimations suggested that the disjunction between the northern populations (within L. rigida) could have originated by intermittent colonization along an ancient river that has been drowned repeatedly by marine transgression. During that time, L. mariae populations could have been established by opportunistic immigrants from Roper River about 15 000 years ago, concurrently with the settlement of indigenous Australians in central Australia, who are thus plausible vectors. Thus, our results rule out the ancient relic hypothesis for the origin of L. mariae.


Assuntos
Arecaceae/genética , DNA de Plantas/genética , Clima Desértico , Evolução Molecular , Fósseis , Genética Populacional , Arecaceae/classificação , Austrália , Teorema de Bayes , Repetições de Microssatélites/genética , Filogeografia , Especificidade da Espécie
13.
J Microbiol Methods ; 192: 106375, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34793853

RESUMO

Caldimonas manganoxidans is a Gram-negative, thermophilic, bioplastic-producing bacterium that is a promising strain to overcome the drawbacks of existing bioplastic manufacturing methods. However, genetic manipulation of this species has not previously been studied. Here, we developed an optimized electrotransformation protocol for C. manganoxidans by screening conditions, including the bacterial growth phase, electroporation buffer, pulse strength, and recovery time. The optimized transformation protocol obtained (3.1 ± 0.78) × 108 colony-forming units/µg DNA of plasmid pBBR1MCS-2. High transformation efficiency was observed when using plasmid DNA isolated from C. manganoxidans. The DNA methylases of Escherichia coli did not affect the transformation efficiency of C. manganoxidans. The electrotransformation technique proposed here will be beneficial for the genetic manipulation of thermophilic Caldimonas species.


Assuntos
Comamonadaceae/genética , Eletroporação/métodos , Transformação Bacteriana/genética , DNA Bacteriano/genética , Plasmídeos/genética
14.
Rinsho Ketsueki ; 52(7): 563-9, 2011 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-21821991

RESUMO

A 70-year-old man was admitted to our hospital with fever, generalized lymphadenopathy and hypoxia in October 2009. Blood examination demonstrated leukocytosis, anemia, thrombocytopenia and hyper γ-globulinemia. Peripheral blood and bone marrow smear showed marked plasma cell proliferation mimicking plasma cell leukemia. However, flow cytometric analysis showed that plasma cells were of polyclonal origin and M-protein was not detected by immunofixation of serum protein. Elevations of soluble interleukin 2 receptor and serum IL-6 were observed. A heavy Epstein-Barr viral load was detected in serum by real-time PCR. Biopsy was obtained from the right inguinal lymph node. The pathological diagnosis was angioimmunoblastic T-cell lymphoma (AITL) and rearrangement of the T-cell receptor Cß1 gene was detected. The patient was treated with CHOP therapy, and all clinical manifestations, including fever, lymphadenopathy, anemia, thrombocytopenia, hyper γ-globulinemia, plasmacytosis and hypoxia, were improved. Only a few reported cases have demonstrated AITL with marked polyclonal plasmacytosis. Although pathological mechanisms of plasmacytosis in AITL patients have not been fully elucidated, it is suggested that IL-6 and IL-10 were involved in its pathogenesis in the present case.


Assuntos
Medula Óssea/patologia , Linfadenopatia Imunoblástica/sangue , Linfadenopatia Imunoblástica/patologia , Linfoma de Células T/sangue , Linfoma de Células T/patologia , Plasmócitos/patologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Linfadenopatia Imunoblástica/tratamento farmacológico , Linfadenopatia Imunoblástica/etiologia , Interleucina-10 , Interleucina-6 , Leucemia Plasmocitária , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/etiologia , Masculino , Prednisolona/administração & dosagem , Resultado do Tratamento , Vincristina/administração & dosagem
15.
RSC Adv ; 11(4): 2096-2102, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35424176

RESUMO

Anodic porous alumina templates with controlled microscale geometrical structures were prepared by a process combining mask formation and subsequent selective etching of the alumina layer. In this process, the anisotropic etching of anodic porous alumina allows the preparation of anodic porous alumina with microhole array patterns having high aspect ratios. The electrodeposition of Ni using the obtained alumina templates generated an array of Ni micropillars with high aspect ratios. The height of Ni micropillars could also be controlled by adjusting the thickness of the anodic porous alumina. The obtained Ni micropillar array with a high aspect ratio was applied as a mold for imprinting. The ordered microstructures of TiO2 with high aspect ratios were prepared by imprinting using the Ni mold.

16.
Rinsho Ketsueki ; 51(3): 189-95, 2010 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-20379113

RESUMO

Factors that affect the response of multiple myeloma patients to thalidomide were evaluated in 40 patients who were not eligible for chemotherapy (untreated: 14, relapse/refractory: 26). The complete response (CR) rate was 2.5%; partial response (PR) 50.0%; minimal response (MR) 25.0%; no change (NC) 12.5%; and progressive disease 10.0%. The response to thalidomide could be evaluated after four weeks of treatment. Significantly higher responses were associated with untreated patients, patients with combined use of thalidomide plus dexamethasone, and patients with kappa light chain. Patients who responded well to thalidomide showed a significantly higher progression-free survival (PFS) rate. In patients with kappa light chain, PFS and overall survival rates were significantly higher than those with lambda light chain. Frequent adverse reactions were numbness (47.5%), constipation (32.5%), and eruption (30.0%). In patients previously treated with vincristine, numbness occurred in a significantly higher percentage of patients.


Assuntos
Mieloma Múltiplo/tratamento farmacológico , Talidomida/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Constipação Intestinal/induzido quimicamente , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Toxidermias/etiologia , Quimioterapia Combinada , Feminino , Humanos , Hipestesia/induzido quimicamente , Cadeias kappa de Imunoglobulina , Cadeias lambda de Imunoglobulina , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Talidomida/efeitos adversos , Resultado do Tratamento
17.
J Imaging ; 6(5)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-34460730

RESUMO

Crowd counting is a challenging task dealing with the variation of an object scale and a crowd density. Existing works have emphasized on skip connections by integrating shallower layers with deeper layers, where each layer extracts features in a different object scale and crowd density. However, only high-level features are emphasized while ignoring low-level features. This paper proposes an estimation network by passing high-level features to shallow layers and emphasizing its low-level feature. Since an estimation network is a hierarchical network, a high-level feature is also emphasized by an improved low-level feature. Our estimation network consists of two identical networks for extracting a high-level feature and estimating the final result. To preserve semantic information, dilated convolution is employed without resizing the feature map. Our method was tested in three datasets for counting humans and vehicles in a crowd image. The counting performance is evaluated by mean absolute error and root mean squared error indicating the accuracy and robustness of an estimation network, respectively. The experimental result shows that our network outperforms other related works in a high crowd density and is effective for reducing over-counting error in the overall case.

18.
RSC Adv ; 10(62): 37657-37661, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-35515160

RESUMO

Ideally ordered TiO2 through-hole membranes were obtained by a combination of Ti substrate pre-patterning and two-layer anodization. The Ti substrate was pre-patterned by Ar ion milling using ideally ordered porous alumina as an etching mask. Each concave pit formed by dry etching acted as an initiation site for hole development during anodization, and ideally ordered anodic porous TiO2 was produced by anodization using an electrolyte containing fluoride ions. Two-layered anodic porous TiO2 samples with different solubilities were formed by heat treatment for the crystallization of the first anodized oxide layer and a subsequent second anodization. The selective dissolution of the lower part of the two-layered porous TiO2 produced an ideally ordered TiO2 through-hole membrane. Using the present process, the repeated preparation of ideally ordered TiO2 membranes can be conducted because the ideally ordered concave array, which corresponds to the hole arrangement at the bottom of the detached TiO2 membrane, is maintained even after detaching the membrane. The obtained samples can be applied to various functional devices, such as photonic crystals and filtration membranes with photocatalytic properties.

19.
Sci Rep ; 10(1): 650, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959766

RESUMO

Oil palm is an important crop for global vegetable oil production, and is widely grown in the humid tropical regions of Southeast Asia. Projected future climate change may well threaten palm oil production. However, oil palm plantations currently produce large amounts of unutilised biological waste. Oil palm stems - which comprise two-thirds of the waste - are especially relevant because they can contain high levels of non-structural carbohydrates (NSC) that can serve as feedstock for biorefineries. The NSC in stem are also considered a potent buffer to source-sink imbalances. In the present study, we monitored stem NSC levels and female reproductive growth. We then applied convergent cross mapping (CCM) to assess the causal relationship between the time-series. Mutual causal relationships between female reproductive growth and the stem NSC were detected, with the exception of a relationship between female reproductive organ growth and starch levels. The NSC levels were also influenced by long-term cumulative temperature, with the relationship showing a seven-month time lag. The dynamic between NSC levels and long-term cumulative rainfall showed a shorter time lag. The lower temperatures and higher cumulative rainfall observed from October to December identify this as a period with maximum stem NSC stocks.


Assuntos
Arecaceae/crescimento & desenvolvimento , Arecaceae/metabolismo , Metabolismo dos Carboidratos , Mudança Climática , Óleo de Palmeira , Reprodução , Amido/metabolismo , Chuva , Estações do Ano , Temperatura
20.
RSC Adv ; 8(4): 2041-2047, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35542576

RESUMO

Nanoporous alumina spheres with an ordered hole arrangement were prepared through a two-step anodization of small Al particles. The hole periodicity in the ordered anodic porous alumina could be controlled by adjusting the anodizing conditions. Nanoporous hollow spheres were also obtained by removal of residual Al in an etchant. Additionally, nanoporous spheres loaded with Au nanoparticles on their surfaces were obtained through electrochemical or chemical deposition of Au nanoparticles. The obtained Au/alumina composite hollow spheres were used as a substrate for surface-enhanced Raman scattering measurements.

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