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1.
Sensors (Basel) ; 24(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38894263

RESUMO

In order to improve the efficiency and accuracy of multitarget detection of soldering defects on surface-mounted components in Printed Circuit Board (PCB) fabrication, we propose a sample generation method using Stable Diffusion Model and ControlNet, as well as a defect detection method based on the Swin Transformer. The method consists of two stages: First, high-definition original images collected in industrial production and the corresponding prompts are input to Stable Diffusion Model and ControlNet for automatic generation of nonindependent samples. Subsequently, we integrate Swin Transformer as the backbone into the Cascade Mask R-CNN to improve the quality of defect features extracted from the samples for accurate detection box localization and segmentation. Instead of segmenting individual components on the PCB, the method inspects all components in the field of view simultaneously over a larger area. The experimental results demonstrate the effectiveness of our method in scaling up nonindependent sample datasets, thereby enabling the generation of high-quality datasets. The method accurately recognizes targets and detects defect types when performing multitarget inspection on printed circuit boards. The analysis against other models shows that our improved defect detection and segmentation method improves the Average Recall (AR) by 2.8% and the mean Average Precision (mAP) by 1.9%.

2.
Sensors (Basel) ; 24(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203139

RESUMO

A novel label-free optical fiber biosensor, based on a microcavity fiber Mach-Zehnder interferometer, was developed and practically demonstrated for DNA detection. The biosensor was fabricated using offset splicing standard communication single-mode fibers (SMFs). The light path of the sensor was influenced by the liquid sample in the offset open cavity. In the experiment, a high sensitivity of -17,905 nm/RIU was achieved in the refractive index (RI) measurement. On this basis, the probe DNA (pDNA) was immobilized onto the sensor's surface using APTES, enabling real-time monitoring of captured complementary DNA (cDNA) samples. The experimental results demonstrate that the biosensor exhibited a high sensitivity of 0.32 nm/fM and a limit of detection of 48.9 aM. Meanwhile, the sensor has highly repeatable and specific performance. This work reports an easy-to-manufacture, ultrasensitive, and label-free DNA biosensor, which has significant potential applications in medical diagnostics, bioengineering, gene identification, environmental science, and other biological fields.


Assuntos
Engenharia Biomédica , Comércio , DNA Complementar , Fibras Ópticas
3.
J Wound Ostomy Continence Nurs ; 51(2): 111-116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527319

RESUMO

PURPOSE: The primary aims of this study were to evaluate the prevalence of wound-related pain (WRP) in patients with chronic wounds and assess the use of pain relief measures. DESIGN: A cross-sectional study. SUBJECTS AND SETTING: A convenience sample of patients with chronic wounds was recruited from outpatient clinics of 12 hospitals covering 7 of 13 cities in the Jiangsu province located in eastern China from July 10 to August 25, 2020. The sample comprised 451 respondents, and their mean age was 54.85 (SD 19.16) years; 56.1% (253/451) patients were male. METHODS: An investigator-designed questionnaire was used to collect pain-related information from patients. The questionnaire consisted of 4 parts: (1) basic demographic and clinical information (patient and wound characteristics); (2) wound baseline pain; (3) wound-related procedural pain and pain relief method; and (4) the effect of WRP on the patient. Pain was assessed using the Numerical Rating Scale (NRS) scored from 0 (no pain) to 10 (worst pain). Severity of pain was based on NRS scores' classification as mild (1-3), moderate (4-6), and severe (7-10). The survey was conducted from July 10 to August 25, 2020. Participants were instructed on use of the NRS and then completed the questionnaire following dressing change independently. RESULTS: The 3 most common types of chronic wounds were traumatic ulcers, surgical wounds, and venous leg ulcers. The 3 most prevalent locations were lower limbs, feet, and thorax/abdomen. Of all patients, 62.5% (282/451) and 93.8% (423/451) patients experienced wound baseline pain and wound-related procedural pain, respectively. The mean score of wound baseline pain was 3.76 (SD 1.60) indicating moderate pain. During wound management, the highest pain score was 6.45 (SD 2.75) indicating severe pain; the most severe pain scores were associated with debridement. The use of drugs to relieve wound pain was low, while the use of nondrug-based analgesia was relatively high. Because of WRP, patients with chronic wounds feared dressing changes, hesitated to move, and showed a decline in sleep quality. CONCLUSIONS: Wound baseline pain and wound-related procedural pain were very common in patients with chronic wounds. In the future, targeted intervention plans should be developed by combining drug-based and nondrug-based analgesia according to pain severity.


Assuntos
Dor Processual , Úlcera Varicosa , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Transversais , Dor , Inquéritos e Questionários , Infecção da Ferida Cirúrgica
4.
Int Wound J ; 20(6): 1903-1910, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36526600

RESUMO

Chronic wounds are very common wound types in clinics which have a prolonged and painful healing process. Chronic wounds affect health-related quality of life (HRQoL) on patients. However, there is no specific instrument to measure the HRQoL in Chinese patients with chronic wounds. Wound-QoL is a questionnaire targeted the experience of health-related life to patients with chronic wounds. The study aims to translate and cross-culturally adapt the Wound-QoL into Chinese and to evaluate its psychometric properties (validity, reliability, floor, and ceiling effect) in a convenience sample of 203 Chinese outpatients with chronic wounds. Reliability was good, with internal consistency of 0.798-0.960 and test-retest reliability of 0.720-0.838. Criterion-related validity was assessed by the correlation coefficient between Wound-QoL and generic European QoL instrument- EQ-5D-5L, which was found statistically significant (P<.001). No signs of floor or ceiling effect could be detected. Further, confirmatory factor analysis (CFA) was used to verify the reliability and validity of the instrument in this study. In conclusion, the Chinese Wound-QoL is a valid and reliable tool for measuring HRQoL in populations with chronic wounds.


Assuntos
Psicometria , Qualidade de Vida , Ferimentos e Lesões , Humanos , População do Leste Asiático/psicologia , Reprodutibilidade dos Testes , Inquéritos e Questionários , Ferimentos e Lesões/psicologia
5.
Appl Opt ; 57(9): 2033-2039, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29603990

RESUMO

In this work, a high-sensitivity and low-cost sensing scheme for measuring intrinsic and induced fiber birefringence change is reported based on a polarimetric fiber laser sensor interrogated by the beat frequency technique. The fiber birefringence measurement is achieved by an external applied strain method. A detailed theoretical analysis of the principle for fiber birefringence measurement is carried out. Two alternative equations are given for determining the change of fiber birefringence, which make it very convenient for users to choose different order beat signals. To verify the performance of the sensing system, the external applied strain-induced fiber birefringence change is measured experimentally. The experiment result shows that the fiber birefringence experiences a linear increase with the increase of applied strain. A strain response coefficient of 4.646×10-11/µÏµ is obtained. Furthermore, the repeatability and stability performances of the polarimetric fiber laser sensor are also investigated.

6.
Opt Lett ; 42(1): 159-162, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28059203

RESUMO

The Letter describes a hybrid multiplexing scheme for a multi-longitudinal-mode fiber laser sensor array by combining wavelength-division multiplexing and frequency-division multiplexing techniques. The proposed multiplexing system consists of many subgroups, each of which has many fiber laser sensors with approximately equal laser-operating wavelengths but different cavity lengths. Each sensor in one subgroup can be interrogated by using frequency-division multiplexing technology because of different sensors with different beat frequencies. For different subgroups, they are characteristic of different laser-operating wavelengths. Each subgroup can be divided into the designed channel by dense wavelength-division multiplexers. At last, a 4×4 sensor multiplexing system was experimentally validated. The strain or temperature applied on each sensor was successfully extracted. The proposed multiplexing system provides a dramatic increase in the number of multiplexed sensors. It greatly reduces the weight, volume, and cost of each sensor and offers a competitive solution for a large-scale monitoring system.

7.
Foods ; 13(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38928766

RESUMO

Food non-denatured processes, such as freeze-drying and grinding, are commonly applied to raw materials with good bioactive functions. Although the functional components are maintained, whether structural and physical changes impact the in vivo function is often ignored in practical situations. Brasenia schreberi mucilage (BSM) has a significant alleviation effect on DSS-induced colitis. This work focused on the influence of non-denatured manufacture on the colonic benefits of BSM-based products. First, three forms of products including fresh mucilage (FM), freeze-dried products (FS), and freeze-dried powder (FP) were prepared. Then, their in vitro physiochemical properties were compared, analyzing their influence on the gut inflammation degree, microbial composition, and SCFA production in mice. The results suggested that the water retention rate of FS and FP was decreased to 34.59 ± 3.85%, and 9.93 ± 1.76%. The viscosity of FM, FS, and FP was 20.14 Pa∙s, 4.92 Pa∙s, and 0.41 Pa∙s, respectively. The freeze-drying and grinding process also damaged the lamellar microstructure of BSM. Then, animal tests showed that colitis mice intervened with FM, FS, and FP had disease activity scores of 2.03, 3.95, and 4.62. Meanwhile, FM notably changed the gut microbial composition and significantly increased propionate and butyrate levels. It seemed that the distinct colitis alleviation efficacy of BSM-based products is attributed to different hydrodynamic properties in the gut. FM had relatively higher viscosity and correspondingly high nutritional density in the gut lumen, which stimulates Firmicutes growth and promotes butyrate production, and thereby exhibited the best efficiency on protecting from colitis.

8.
Foods ; 13(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38397495

RESUMO

Brasenia schreberi J.F. Gmel (BS) is rich in mucilage, which has diverse biological activities, and is utilized in the food and pharmaceutical industries due to its nutritional value. Proteomics analysis was employed to investigate the cause of mucilage disappearance in BS and its effect on nutrient accumulation. Among the 2892 proteins identified, 840 differentially expressed proteins (DEPs) were found to be involved in mucilage development. By comparing the expression patterns and functions and pathway enrichment, the DEPs mainly contributed to carbon and energy metabolism, polysaccharide metabolism, and photosynthesis. Our study also revealed positive correlations between mucilage accumulation and tryptophan metabolism, with high levels of indole-3-acetic (IAA) contributing to mucilage accumulation. Furthermore, environmental changes and particularly excessive nutrients were found to be detrimental to mucilage synthesis. Overall, in the absence of various stimuli in the growing environment, BS accumulates more nutrients within the plant itself instead of producing mucilage.

9.
J Nanosci Nanotechnol ; 13(8): 5580-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882798

RESUMO

Highly ordered TiO2 nano-tube arrays (TNTAs) photoelectrodes were prepared through anodization method, followed by annealing treatment. Morphologies and structures of the as-prepared TNTAs samples were investigated through scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, the optical and photoelectrochemical (PECH) properties were investigated through ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) and transient photocurrent response. Furthermore, the photodecomposition performances were investigated through the yield of hydroxyl (*OH) radicals and photocatalytic (PC) degradation of RhB under Xenon light irradiation. Results indicated that the TNTAs samples annealed at 723 K exhibited the highest photocurrent response, PC performance and yield of *OH radicals, in which 60.8% of RhB could be degraded by PC degradation within 60 min. The high PC performance could mainly be attributed to the anatase structure, high crystallinity and highly ordered nano-tubular structure, which favored the transfer and separation of photoinduced charge carriers. This study suggests that highly ordered nano-structure could provide superior pathway for the charge transfer and separation.

10.
Food Funct ; 14(8): 3564-3575, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36946057

RESUMO

Ulcerative colitis (UC) is a growing health concern in humans, but it can be prevented by using special dietary strategies. Young stems and leaves of Brasenia schreberi (BS) are coated with a special polysaccharide hydrogel (BS mucilage) which can be beneficial for colon health. The aim of this study was to investigate the preventive effects of BS mucilage against UC in a DSS-treated mouse model. Although containing only 0.3% solid content, our research showed that BS mucilage effectively attenuated the disease activity index (DAI) and the spleen index and downregulated IL-1ß, IL-18, IL-6 and CAT mRNA levels in DSS-treated mice, which is a promising UC alleviation function. Additionally, BS mucilage also improved the propionate and butyrate levels in mouse feces and alleviated the imbalanced gut microbiota induced by DSS. The abundance of pro-inflammatory and colorectal cancer related bacteria, such as Prevotella, Ruminococcus, Acutalibacter and Christensenella, was decreased by BS mucilage feeding, whereas the abundance of anti-inflammatory and SCFA-producing bacteria including Alistipes and Odoribacter was increased. In conclusion, the current study shows that the daily consumption of BS mucilage could be an effective way to prevent UC in mice, via modulation of gut microbiota.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Hidrogéis , Colo , Polissacarídeos/farmacologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Colite/induzido quimicamente , Camundongos Endogâmicos C57BL
11.
Metabolism ; 144: 155376, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36521551

RESUMO

BACKGROUND: Renal interstitial fibrosis (RIF) is one of the main features of diabetic nephropathy (DN), but the molecular mechanisms mediating RIF in DN has yet been fully understood. S100A8 and S100A9 are the proteins associated with immune and inflammation response. Here we reported the expression of S100A8 and S100A9 were significantly increased on tubular epithelial cells in diabetic kidneys through a proteomic analysis. METHODS: We detected the expression of S100A8/A9 in diabetic kidneys by using immunoblotting, real-time PCR and immunostaining. RNA silencing and overexpression were performed by using S100A8/A9 expression/knockdown lentivirus to investigate the connection between S100A8/A9 and epithelial to mesenchymal transition (EMT) process. We also identify the expression of TLR4/NFκB pathway-related molecules in the case mentioned above. Afterwards a CO-IP assay was used to verify that compound AB38b ameliorates the EMT by interfering S100A8/A9 expression. RESULTS: The expression of S100A8 and S100A9 were significantly increased on tubular epithelial cells in diabetic kidneys. S100A8/A9 knocking-down alleviate and over-expression promote the renal interstitial fibrosis of diabetic mice. Mechanically, high levels of S100A8/A9 expression in tubular epithelial cells during diabetic condition activated the TLR4/NF-κB signal pathway which promoted the EMT process and finally led to RIF progression. S100A8/A9 knockdown ameliorated RIF of diabetic mice. Further experiments revealed that compound AB38b inhibited the EMT progression of tubular epithelial cells induced by S100A8/A9 through interfering the expressions of S100A8/A9. CONCLUSIONS: Our study suggest that abnormal expression of S100A8/A9 in the disease condition promotes EMT process and RIF through TLR4/NF-κB signal pathway. Using small molecular inhibitor AB38b to inhibit the abnormal expressions of S100A8/A9 might be a novel therapeutic strategy in treating DN.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Camundongos , Animais , Nefropatias Diabéticas/metabolismo , NF-kappa B/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Transição Epitelial-Mesenquimal , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Proteômica , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Fibrose
12.
Front Med (Lausanne) ; 8: 719958, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047519

RESUMO

Objective: To identify novel immune-related genes expressed in primary Sjögren's syndrome (pSS). Methods: Gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were screened. The differences in immune cell proportion between normal and diseased tissues were compared, weighted gene co-expression network analysis was conducted to identify key modules, followed by a protein-protein interaction (PPI) network generation and enrichment analysis. The feature genes were screened and verified using the GEO datasets and quantitative real-time PCR (RT-qPCR). Results: A total of 345 DEGs were identified, and the proportions of gamma delta T cells, memory B cells, regulatory T cells (Tregs), and activated dendritic cells differed significantly between the control and pSS groups. The turquoise module indicated the highest correlation with pSS, and 252 key genes were identified. The PPI network of key genes showed that RPL9, RBX1, and RPL31 had a relatively higher degree. In addition, the key genes were mainly enriched in coronavirus disease-COVID-2019, hepatitis C, and influenza A. Fourteen feature genes were obtained using the support vector machine model, and two subtypes were identified. The genes in the two subtypes were mainly enriched in the JAK-STAT, p53, and toll-like receptor signaling pathways. The majority of the feature genes were upregulated in the pSS group, verified using the GEO datasets and RT-qPCR analysis. Conclusions: Memory B cells, gamma delta T cells, Tregs, activated dendritic cells, RPL9, RBX1, RPL31, and the feature genes possible play vital roles in the development of pSS.

13.
Biochem Pharmacol ; 192: 114675, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252407

RESUMO

Podocyte injury following abnormal podocyte autophagy plays an indispensable role in diabetic nephropathy (DN), therefore, restoration of podocyte autophagy is considered as a feasible strategy for the treatment of DN. Here, we investigated the preventive effects of sarsasapogenin (Sar), the main active ingredient in Anemarrhena asphodeloides Bunge, on the podocyte injury in diabetic rats, and tried to illustrate the mechanisms underlying the effects in high glucose (HG, 40 mM)-treated podocytes (MPs). Diabetes model was established in rats with single streptozocin (60 mg· kg-1) intraperitoneal administration. The rats were then treated with Sar (20, 60 mg· kg-1· d-1, i.g.) or a positive control drug insulin (INS) (40 U· kg-1· d-1, i.h.) for 10 weeks. Our results showed that both Sar and insulin precluded the decreases of autophagy-related proteins (ATG5, Beclin1 and LC3B) and podocyte marker proteins (podocin, nephrin and synaptopodin) in the diabetic kidney. Furthermore, network pharmacology was utilized to assess GSK3ß as the potential target involved in the action of Sar on DN and were substantiated by significant changes of GSK3ß signaling in the diabetic kidney. The underlying protection mechanisms of Sar were explored in HG-treated MPs. Sar (20, 40 µM) or insulin (50 mU/L) significantly increased the expression of autophagy- related proteins and podocyte marker proteins in HG-treated MPs. Furthermore, Sar or insulin treatment efficiently regulatedphosphorylation at activation and inhibition sites of GSK3ß. To sum up, this study certifies that Sar meliorates experimental DN through targeting GSK3ß signaling pathway and restoring podocyte autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Nefropatias Diabéticas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Glicogênio Sintase Quinase 3 beta/metabolismo , Podócitos/efeitos dos fármacos , Espirostanos/administração & dosagem , Animais , Autofagia/fisiologia , Nefropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Podócitos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
14.
Front Pharmacol ; 12: 792777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069207

RESUMO

Podocytes injury is one of the leading causes of proteinuria in patients with diabetic nephropathy (DN), and is accompanied by podocytes apoptosis and the reduction of podocyte markers such as synaptopodin and nephrin. Therefore, attenuation of podocyte apoptosis is considered as an effective strategy to prevent the proteinuria in DN. In this study, we evaluated the anti-podocyte-apoptosis effect of quercetin which is a flavonol compound possessing an important role in prevention and treatment of DN and verified the effect by using db/db mice and high glucose (HG)-induced mouse podocytes (MPs). The results show that administration of quercetin attenuated the level of podocyte apoptosis by decreasing the expression of pro-apoptotic protein Bax, cleaved caspase 3 and increasing the expression of anti-apoptotic protein Bcl-2 in the db/db mice and HG-induced MPs. Furthermore, epidermal growth factor receptor (EGFR) was predicted to be the potential physiological target of quercetin by network pharmacology. In vitro and vivo experiments confirmed that quercetin inhibited activation of the EGFR signaling pathway by decreasing phosphorylation of EGFR and ERK1/2. Taken together, this study demonstrates that quercetin attenuated podocyte apoptosis through inhibiting EGFR signaling pathway, which provided a novel approach for further research of the mechanism of quercetin in the treatment of DN.

15.
Nanomaterials (Basel) ; 10(4)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235628

RESUMO

Bi(NO3)3·5H2O and (NH4)6Mo7O24·4H2O were used as precursors to synthesize flaky γ-Bi2MoO6 samples by a hydrothermal method, and Pt/γ-Bi2MoO6 samples with different mass fractions were prepared by an NaBH4 reduction method. Alpha alkylation of benzyl alcohol and acetophenone with photocatalysts under visible light irradiation was performed, and the activity of 4 wt % Pt/γ-Bi2MoO6 (γ-Bi2MoO6 was prepared by a nitric acid method, pH = 9, and reaction temperature 180 °C) was the best. The photocatalytic reaction conditions were optimized by changing various kinds of variables, such as the type of catalyst, solvent, and base, and the amount of base, catalyst, and reactant. The optimal conditions for the organic reaction were 75 mg 4 wt % Pt/γ-Bi2MoO6, 6 mL n-heptane, 1.2 mmol NaOH, 1 mmol acetophenone, and 3 mmol benzyl alcohol. Under the optimal reaction conditions, the effects of different light wavelengths and light intensities on the reaction were measured, and the cycling ability of the photocatalyst was tested. After five cycles, the photochemical properties of the catalyst were relatively stable. Finally, the active substances were identified (such as electrons (e-), holes (h+), hydroxyl radicals (•OH), and superoxide radicals (•O2-).

16.
Oncol Lett ; 20(4): 74, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32863907

RESUMO

Hepatocellular carcinoma (HCC) is a malignant tumor with high incidence and high risk. Study of the role and mechanism of miRNAs are a hot spot of research providing new treatment ideas in malignant tumors. The effect of miR-642a on HCC progression and the underlying molecular mechanism were investigated. Expression of miR-642a and SEMA4C was measured by western blot analysis and RT-PCR. miR-642a expression was elevated while SEMA4C expression was attenuated in HCC tissues and cells. Results of luciferase reporter and western blot analyses show that miR-642a modulated SEMA4C expression by binding to its 3'UTR. Moreover, miR-642a negatively regulated SEMA4C expression. HCC cell migration and invasion was tested by Transwell assays. The findings revealed that the number of migrated and invaded cells were reduced by miR-642a mimic and raised by miR-642a inhibitor, indicating that miR-642a showed a suppression effect on HCC cell migration and invasion. Additionally, the migration and invasion of HCC cells were inhibited by SEMA4C siRNA, and SEMA4C reversed miR-642a effect on HCC migration and invasion. Furthermore, p38 MAPK signaling pathway was proven to be inhibited by miR-642a mimic, whereas facilitated by miR-642a inhibitor and SEMA4C siRNA could overturn the promotion effect of miR-642a inhibitor. Briefly, miR-642a targeted SEMA4C to repress HCC cell migration and invasion through p38 MAPK signaling pathway providing a new strategy for treatment of HCC patients.

17.
Appl Opt ; 48(11): 2171-7, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19363557

RESUMO

A method for testing the physical and optical properties of hydrogel thin films is reported based on using long-period fiber gratings. For humidity levels from 50% to 70% RH, a wavelength decrease of 11.0 nm is observed, with a sensitivity of 0.6 nm/%RH. For humidity levels from 70% to 98% RH, a wavelength increase of 6.3 nm is seen, with a sensitivity of 0.2 nm/%RH. For humidity levels greater than 60% RH, the transmission loss at resonance increases rapidly, showing a high degree of sensitivity of 0.5 dB/% RH. The blueshift of the wavelength was seen to be due to a thickening of the overlay, while the redshift of wavelength is due to the contribution of the drop in refractive index of the overlay. The results match well with what is expected theoretically.

18.
BMC Genomics ; 8: 366, 2007 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17925038

RESUMO

BACKGROUND: The nucleotide compositional asymmetry between the leading and lagging strands in bacterial genomes has been the subject of intensive study in the past few years. It is interesting to mention that almost all bacterial genomes exhibit the same kind of base asymmetry. This work aims to investigate the strand biases in Chlamydia muridarum genome and show the potential of the Z curve method for quantitatively differentiating genes on the leading and lagging strands. RESULTS: The occurrence frequencies of bases of protein-coding genes in C. muridarum genome were analyzed by the Z curve method. It was found that genes located on the two strands of replication have distinct base usages in C. muridarum genome. According to their positions in the 9-D space spanned by the variables u1 - u9 of the Z curve method, K-means clustering algorithm can assign about 94% of genes to the correct strands, which is a few percent higher than those correctly classified by K-means based on the RSCU. The base usage and codon usage analyses show that genes on the leading strand have more G than C and more T than A, particularly at the third codon position. For genes on the lagging strand the biases is reverse. The y component of the Z curves for the complete chromosome sequences show that the excess of G over C and T over A are more remarkable in C. muridarum genome than in other bacterial genomes without separating base and/or codon usages. Furthermore, for the genomes of Borrelia burgdorferi, Treponema pallidum, Chlamydia muridarum and Chlamydia trachomatis, in which distinct base and/or codon usages have been observed, closer phylogenetic distance is found compared with other bacterial genomes. CONCLUSION: The nature of the strand biases of base composition in C. muridarum is similar to that in most other bacterial genomes. However, the base composition asymmetry between the leading and lagging strands in C. muridarum is more significant than that in other bacteria. It's supposed that the remarkable strand biases of G/C and T/A are responsible for the appearance of separate base or codon usages in C. muridarum. On the other hand, the closer phylogenetic distance among the four bacterial genomes with separate base and/or codon usages is necessary rather than occasional. It's also shown that the Z curve method may be more sensitive than RSCU when being used to quantitatively analyze DNA sequences.


Assuntos
Pareamento de Bases , Chlamydia muridarum/genética , Genes Bacterianos , Códon , DNA Bacteriano/genética
19.
J Virol Methods ; 146(1-2): 389-92, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17716751

RESUMO

Using the Z curve method, the protein-coding genes in AmEPV genome are re-predicted. On the basis of the parameters trained on the experimentally validated genes, all of the 30 experimentally validated genes and 67 putative genes are predicted correctly as coding genes. The sensitivities of the present method for self-test and cross-validation are all 100% based on these test sets. Thirty-eight annotated conserved and hypothetical genes are predicted as non-coding ORFs. The number of re-predicted protein-coding genes in AmEPV is 256. It is significantly less than the number 294 reported in the original annotation. After extending the present method trained in AeEPV genome to the other entomopoxvirus genome, it is found that 116 of the 123 known and putative genes are predicted correctly as coding. Six of the seven falsely missed genes are less than 300bp. The present method could be extended to other poxvirus genomes with or without adaptation of training sets.


Assuntos
Algoritmos , Biologia Computacional , Entomopoxvirinae/genética , Genes Virais , Genoma Viral , Proteínas Virais/genética , Bases de Dados de Ácidos Nucleicos , Fases de Leitura Aberta/genética
20.
J Environ Sci (China) ; 18(1): 33-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-20050545

RESUMO

By using a self-made carbon/polytetrafluoroethylene (C/PTFE) O2-fed as cathode and Ti/IrO2/RuO2 as anode, the effects of electrochemical oxidation of phenol and the coal-gas wastewater containing phenol were studied. The terylene diaphragm which kept pH >12 in cathodic compartment and pH < 1 in the anodic compartment was selected in the experiment in comparison with the other types of diaphragm. Furthermore, hydroxyl radical (HO*) was determined in the cathodic compartment of the diaphragm cell by electron spin resonance spectrum (ESR) and the fluorescence spectra. Compared with pH, the accumulated H2O2 and the COD removal of the no-diaphragm cell, the mechanism of electrochemical oxidation in the terylene diaphragm cell was supposed. The degradation of phenol was supposed to be cooperative oxidation by direct or indirect electrochemical oxidation at the anode and H2O2, HO* produced by oxygen reduction at the cathode. The mineralization of phenol in the diaphragm cell was better than that in the no-diaphragm cell. When the coal-gas wastewater was treated by the electrolysis system with terylene diaphragm, the average removal efficiency of the volatile phenol and COD were 100% and 79.6%, respectively.


Assuntos
Eletroquímica , Polietilenotereftalatos/química , Espectroscopia de Ressonância de Spin Eletrônica , Oxirredução , Espectrometria de Fluorescência
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