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1.
Mol Cell ; 69(3): 385-397.e8, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29336876

RESUMO

Heterochromatin plays important roles in transcriptional silencing and genome maintenance by the formation of condensed chromatin structures, which determine the epigenetic status of eukaryotic cells. The trimethylation of histone H3 lysine 9 (H3K9me3), a target of heterochromatin protein 1 (HP1), is a hallmark of heterochromatin formation. However, the mechanism by which HP1 folds chromatin-containing H3K9me3 into a higher-order structure has not been elucidated. Here we report the three-dimensional structure of the H3K9me3-containing dinucleosomes complexed with human HP1α, HP1ß, and HP1γ, determined by cryogenic electron microscopy with a Volta phase plate. In the structures, two H3K9me3 nucleosomes are bridged by a symmetric HP1 dimer. Surprisingly, the linker DNA between the nucleosomes does not directly interact with HP1, thus allowing nucleosome remodeling by the ATP-utilizing chromatin assembly and remodeling factor (ACF). The structure depicts the fundamental architecture of heterochromatin.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Heterocromatina/metabolismo , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/genética , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/genética , Microscopia Crioeletrônica/métodos , DNA/metabolismo , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Metilação , Nucleossomos/metabolismo , Ligação Proteica , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
2.
Nanotechnology ; 35(24)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38387088

RESUMO

The recombination of photoexcited electron-hole pairs greatly limits the degradation performance of photocatalysts. Ultrasonic cavitation and internal electric field induced by the piezoelectric effect are helpful for the separation of electron-hole pairs and degradation efficiency. The activated foam carbon (AFC) owing to its high surface area is often used as the substrate to grow catalysts to provide more reactive active sites. In this work, CuO@BaTiO3(CuO@BTO) heterostructure is prepared by hydrothermal method on the surface of AFC to investigate the ultrasonic piezoelectric catalysis effect. X-ray diffraction (XRD), Raman spectroscopy, energy dispersive x-ray spectroscopy (EDS) and scanning electron microscopy (SEM) were used to analyze the structure and morphology of CuO-BTO/AFC composite. It is found that the CuO-BTO/AFC composite exhibits excellent piezo-catalytic performance for the degradation of organics promoted by ultrasonic vibration. The CuO-BTO/AFC composite can decompose methyl orange and methylene blue with degradation efficiency as high as 93.9% and 97.6% within 25 min, respectively. The mechanism of piezoelectricity enhanced ultrasound supported catalysis effect of system CuO-BTO/AFC is discussed. The formed heterojunction structure between BTO and CuO promotes the separation of positive and negative charges caused by the piezoelectric effect.

3.
Prev Sci ; 25(4): 673-684, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38748316

RESUMO

Parenting programs have been shown to empower parents and prevent mental health problems in children. However, few programs are designed to promote wellbeing, which led to the development of the Swedish-promotive universal program, "All Children in Focus" (ACF). This study aimed to understand the effects of parents' participation in the ACF program on parents' emotion regulation and parenting practices over a 6-month follow-up and if intervention-produced changes predict child wellbeing (CW). Parental self-efficacy (PSE) was also included to assess the relation with parental outcomes and CW. This is an evaluation of a multicenter randomized waitlisted control trial conducted in Stockholm County, Sweden, with parents of children aged 3 to 12 years (n = 621) in 2012. Parents were randomized 1:1 to enter the program or to a waitlist. Questionnaires were completed by parents at baseline, post-intervention, and 6 months post-baseline. We used generalized mixed modeling to test effects on parental outcomes over time and regression analyses to study the predictive role of parental outcomes on CW. From baseline to the post- and to the 6-month follow-ups, parents in the intervention group reported greater levels of emotion regulation skills, cognitive reappraisal, and positive parenting than did parents in the control group. A decrease in negative and harsh parenting was evident in both groups, although it was greater in the intervention group. An increase in PSE was associated with high negative parenting at baseline in the intervention group. Child gender moderated positive parenting, suggesting that parents of girls in the intervention group had more favorable development of positive strategies. The findings indicate that a change in PSE predicts a change in CW at 6 months. The ACF program can be used to strengthen and develop parenting. This study advances our knowledge about the potential advantages of using a health-promoting approach to strengthen the wellbeing of families in the general population. Clinical trial registration: ISRCTN70202532 Current Controlled Trials.


Assuntos
Poder Familiar , Humanos , Suécia , Feminino , Masculino , Pré-Escolar , Criança , Seguimentos , Inquéritos e Questionários , Adulto
4.
Environ Res ; 222: 115303, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36642126

RESUMO

The synthesis of multifunctional cathode with high-efficiency and stable catalytic activity for simultaneously producing and activating H2O2 is an effective way for promoting the performance of heterogeneous electro-Fenton process (HEF). In addition, accelerating mass transfer by adopting a flow-through reactor is also great importance because of its better utilization of catalysts and adequate contact of the contaminant with the oxidants generated on the electrode surface. Herein, a novel flow-through HEF (FHEF) system was designed for the degradation of trimethoprim (TMP) using bifunctional cathode with a sandwich structure FeOCl nanosheets loaded onto carbon cloth (CC) and activated carbon fiber (ACF) (FeOCl/CC/ACF). The cathode exhibited excellent performance in activating H2O2 for the in-situ generation of hydroxyl radicals (•OH). The electron spin resonance (ESR) measurements and radical quenching tests proved that the high production of •OH in the FHEF process was favorable to the high catalytic efficiency. 25 mg L-1 TMP was entirely degraded after 60 min, with the TOC removal of 62.6% (180 min) at pH 6.8, 9.0 mA cm-2, and flux rate 210 mL min-1. Moreover, the degradation rate still could reach 83% (60 min) after 10 cycles without obvious valence and crystal phase changes. Simultaneously, the current utilization rate has also been greatly enhanced, with an average current efficiency of 69.9% and a low energy consumption of 0.28 kWh kg-1. The reasonable degradation pathways for TMP were proposed based on the UPLC-QTOF-MS/MS results. Finally, the results of toxicological simulation showed a declining trend in the toxicity of the samples during TMP degradation. These results claim that the FeOCl/CC/ACF-FHEF system is an efficient and economical technology for the treatment of organic contaminants in effluents.


Assuntos
Trimetoprima , Poluentes Químicos da Água , Carvão Vegetal , Poluentes Químicos da Água/análise , Peróxido de Hidrogênio/química , Fibra de Carbono , Espectrometria de Massas em Tandem , Oxirredução , Eletrodos , Concentração de Íons de Hidrogênio
5.
Sensors (Basel) ; 23(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37112232

RESUMO

Spot detection has attracted continuous attention for laser sensors with applications in communication, measurement, etc. The existing methods often directly perform binarization processing on the original spot image. They suffer from the interference of the background light. To reduce this kind of interference, we propose a novel method called annular convolution filtering (ACF). In our method, the region of interest (ROI) in the spot image is first searched by using the statistical properties of pixels. Then, the annular convolution strip is constructed based on the energy attenuation property of the laser and the convolution operation is performed in the ROI of the spot image. Finally, a feature similarity index is designed to estimate the parameters of the laser spot. Experiments on three datasets with different kinds of background light show the advantages of our ACF method, with comparison to the theoretical method based on international standard, the practical method used in the market products, and the recent benchmark methods AAMED and ALS.

6.
J Environ Sci (China) ; 127: 641-651, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522093

RESUMO

Non-thermal plasma (NTP) surface modification technology is a new method to control the surface properties of materials, which has been widely used in the field of environmental protection because of its short action time, simple process and no pollution. In this study, Cu/ACF (activated carbon fiber loaded with copper) adsorbent was modified with NTP to remove H2S and PH3 simultaneously under low temperature and micro-oxygen condition. Meanwhile, the effects of different modified atmosphere (air, N2 and NH3), specific energy input (0-13 J/mL) and modification time (0-30 min) on the removal of H2S and PH3 were investigated. Performance test results indicated that under the same reaction conditions, the adsorbent modified by NH3 plasma with 5 J/mL for 10 min had the best removal effect on H2S and PH3. CO2 temperature-programmed desorption and X-ray photoelectron spectroscopy (XPS) analyzes showed that NH3 plasma modification could introduce amino functional groups on the surface of the adsorbent, and increase the types and number of alkaline sites on the surface. Brunauer-Emmett-Teller and scanning electron microscopy showed that NH3 plasma modification did not significantly change the pore size structure of the adsorbent, but more active components were evenly exposed to the surface, thus improving the adsorption performance. In addition, X-ray diffraction and XPS analysis indicated that the consumption of active components (Cu and Cu2O) and the accumulation of sulfate and phosphate on the surface and inner pores of the adsorbent are the main reasons for the deactivation of the adsorbent.


Assuntos
Gases em Plasma , Adsorção , Carvão Vegetal , Óxidos de Enxofre , Espectroscopia Fotoeletrônica
7.
BMC Genomics ; 23(1): 601, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982422

RESUMO

BACKGROUND: Due to the prolonged usage of Bt-based biopesticides and Bt-transgenic crops worldwide, insects are continually developing resistance against Cry toxins. This resistance may occur if any mechanistic step in the insecticidal process is disrupted possibly because of the alteration in Cry-receptor binding affinity due to mutation in receptor genes. Compared to other lepidopteran insects, Cry receptor-related research has made asymmetric progress in the model insect Galleria mellonella. RESULTS: Present study describes the molecular characterization and functional analysis of five Cry toxin receptor-related genes (prohibitin, GLTP, α-amylase, ADAM and UDP-GT) and a gut repair gene (arylphorin) from the gut tissues of G. mellonella. Protein-protein docking analysis revealed that Cry1AcF putatively binds with all the five candidate proteins, suggesting their receptor-like function. These receptor-like genes were significantly overexpressed in the gut tissues of fourth-instar G. mellonella larvae upon early exposure to a sub-lethal dose of Cry1AcF toxin. However, targeted knockdown (by using bacterially-expressed dsRNAs) of these genes led to variable effect on insect susceptibility to Cry1AcF toxin. Insects pre-treated with prohibitin and α-amylase dsRNA exhibited significant reduction in Cry1AcF-induced mortality, suggesting their probable role as Cry receptor. By contrast, insects pre-treated with GLTP, ADAM and UDP-GT dsRNA exhibited no significant decline in mortality. This maybe explained by the possibility of RNAi feedback regulation (as few of the receptors belong to multigene family) or redundant role of GLTP, ADAM and UDP-GT in Cry intoxication process. CONCLUSION: Since the laboratory culture of G. mellonella develop Bt resistance quite rapidly, findings of the current investigation may provide some useful information for future Cry receptor-related research in the model insect.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Proteínas de Bactérias/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Larva/genética , Mariposas/genética , Mariposas/metabolismo , Proibitinas , Interferência de RNA , Difosfato de Uridina/metabolismo , Difosfato de Uridina/farmacologia , alfa-Amilases/genética , alfa-Amilases/metabolismo , alfa-Amilases/farmacologia
8.
Insect Mol Biol ; 31(4): 434-446, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35266587

RESUMO

Crystal (Cry) toxins produced from the soil bacterium, Bacillus thuringiensis (Bt), have gained worldwide attention for long due to their insecticidal potential. A number of receptor proteins located on the epithelial cells of the larval midgut were shown to be crucial for Cry intoxication in different insect pests belonging to order Lepidoptera, Diptera and Coleoptera. A beehive pest, Galleria mellonella, serves as an excellent insect model for biochemical research. However, information on the Cry receptor-like genes in G. mellonella is limited. In the present study, the full-length sequences of four putative Cry receptor genes (ABC transporter, alkaline phosphatase, aminopeptidase N and cadherin) were cloned from G. mellonella. All these receptor genes were substantially upregulated in the midgut tissue of fourth-instar G. mellonella larvae upon early exposure (6 h) to a sub-lethal dose of Cry1AcF toxin. Oral and independent delivery of bacterially-expressed dsRNAs corresponding to four receptor genes in G. mellonella suppressed the transcription of target receptors which in turn significantly reduced the larval sensitivity to Cry1AcF toxin. As the laboratory populations of G. mellonella develop Bt resistance in a relatively short time, molecular characterization of Cry receptor genes in G. mellonella performed in the present study may provide some useful information for future research related to the genetic basis of Bt resistance in the model insect.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Bacillus thuringiensis/química , Bacillus thuringiensis/genética , Proteínas de Bactérias/química , Endotoxinas/metabolismo , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Insetos/metabolismo , Larva/genética , Larva/metabolismo , Mariposas/genética , Mariposas/metabolismo , Receptores de Superfície Celular
9.
Chem Eng J ; 430: 132845, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36569380

RESUMO

Glucocorticoids (GCs) have drawn great concern due to their widespread contamination in the environment and application in treating patients with COVID-19. Due to the lack of data about GC removal using advanced treatment processes, a novel Paralleling and bubbling corona discharge reactor (PBCD) combined with iron-loaded activated-carbon fibre (Fe-ACF) was addressed in this study to degrade GCs represented by Hydrocortisone (HC) and Betamethasone (BT). The results showed that the PBCD-based system can degrade GCs effectively and can achieve effective sterilization. The removal rates of GCs were ranked as PBCD/Fe-ACF > PBCD/ACF > PBCD. The concentration of E. coli was reduced from 109 to 102 CFU/mL after 60 min of PBCD-based system treatment. The abundance of bacteria in actual Hospital wastewater (HWW) was significantly reduced. Plasma changed the physical and chemical properties of ACF and Fe-ACF by etching axial grooves and enhancing stretching vibrations of surface functional groups, thus promoting adsorption and catalytic degradation. For GC degradation, the functional reactive species were identified as •OH, 1O2, and •O2 radicals. Possible degradation pathways for HC and BT were proposed, which mainly included defluorination, keto acid decarboxylation, demethylation, intramolecular cyclization, cleavage and ester hydrolysis, indicating a reduction in GC toxicity. Since GCs are widely used in patients with COVID-19 and their wastewater needs to be sterilized simultaneously, the intensive and electrically driven PBCD-based system is promising in GC pollution control and sterilization in terminal water treatment facilities.

10.
Sensors (Basel) ; 22(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35898059

RESUMO

An acoustic matching layer is an essential component of an ultrasound transducer to achieve maximum ultrasound transmission efficiency. Here, we develop a flexible printed circuit board (FPCB) with a composite structure consisting of multiple polyimide and copper layers and demonstrate it as a novel acoustic matching layer. With a flexible substrate and robust ACF bonding, the FPCB not only serves as an acoustic matching layer between piezoelectric elements and the surrounding medium but also as a ground for the electrical connection between the transducer array elements and the folded substrate. A 1D linear ultrasound transducer array with the FPCB matching layer exhibits larger output pressure, wider -3dB bandwidth, and higher ultrasound beam intensity compared to that of an ultrasound transducer array with the alumina/epoxy matching layer, which is one of the most commonly applied composite matching layers. The enhanced transmission performance verifies that the proposed FPCB is an excellent matching layer for 1D linear ultrasound transducer arrays.


Assuntos
Acústica , Transdutores , Impedância Elétrica , Desenho de Equipamento , Ultrassonografia
11.
Medicina (Kaunas) ; 58(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36556972

RESUMO

Background and Objectives: Aberrant crypt foci (ACF) are one of the earliest putative preneoplastic and, in some cases, neoplastic lesions in human colons. Many studies have confirmed the reduction of ACFs and colorectal adenomas after treatment with acetylsalicylic acid (ASA) commonly referred to as ASA; however, the minimum effective dose of ASA and the duration of use has not been fully elucidated. The objective of our study was to assess the significance of low dose ASA (75-mg internally once daily) to study the chemopreventive effect of ASA in ACF and adenomas development in patients taking this drug for a minimum period of 10 years. Materials and Methods: Colonoscopy, combined with rectal mucosa staining with 0.25% methylene blue, was performed on 131 patients. The number of rectal ACF in the colon was divided into three groups: ACF < 5; ACF 5−10; and ACF > 10. Patients were divided into two groups: the "With ASA" group (the study group subjects taking ASA 75-mg daily for 10 years); and "Without ASA" group (control group subjects not taking ASA chronically). The incidence of different types of rectal ACF and colorectal polyps in both groups of subjects was analysed and ascertained. Results: Normal ACF was found in 12.3% in the study group vs. 87.7% control group, hyperplastic 22.4% vs. 77.6%, dysplastic 25% vs. 75%, mixed 0% vs. 100%. Treatment with ASA affects the occurrence of colorectal adenomas. The amount of dysplastic ACFs was lower in the study group than in the control group. The increase in dysplastic ACFs decreases with age in both groups, with the increase greater in those not taking ASA. Conclusions: Patients who take persistent, chronic (>10 years) low doses of ASA have a lower total number of all types of rectal ACFs and adenomas compared to the control group.


Assuntos
Focos de Criptas Aberrantes , Adenoma , Neoplasias Colorretais , Humanos , Focos de Criptas Aberrantes/tratamento farmacológico , Focos de Criptas Aberrantes/epidemiologia , Focos de Criptas Aberrantes/patologia , Aspirina/uso terapêutico , Reto , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/tratamento farmacológico , Adenoma/prevenção & controle , Adenoma/patologia
12.
Comput Econ ; 60(3): 901-923, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34334954

RESUMO

Scientific and effective tail risk measurement and early warning are key points and difficulties in the identification and control of major risks in capital markets. In this paper, we use the autoregressive conditional Fréchet model (AcF) to construct a tail risk measurement index for the capital market in China. The tail risk status identified by the scientific index method is used as a monitoring anchor to construct and optimize a tail risk early warning model based on machine learning algorithms. The study yields three findings. (1) The AcF model can overcome the shortcomings of traditional models in tail risk measurement and significantly improve the tail risk measurement efficiency of the capital market. (2) Tail risk synergies between equity and bond markets are significantly stronger than yield synergies, and the tail risk measure index has the role of a leading indicator of significant risk in capital markets. (3) Based on the joint test of risk status and crisis identification efficiency, the Logit model of crisis identification fails whereas the tail risk warning model optimized by machine learning algorithms can accurately identify crises and significant risks. The optimal early warning model pairings for the stock market and bond market are the oversampling-random forest algorithm and the double sampling-random forest algorithm, respectively, with out-of-sample crisis warning accuracies of 81.94% and 90.20%, respectively.

13.
Am J Hum Genet ; 103(6): 1009-1021, 2018 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-30471716

RESUMO

To date, mutations in 15 actin- or microtubule-associated genes have been associated with the cortical malformation lissencephaly and variable brainstem hypoplasia. During a multicenter review, we recognized a rare lissencephaly variant with a complex brainstem malformation in three unrelated children. We searched our large brain-malformation databases and found another five children with this malformation (as well as one with a less severe variant), analyzed available whole-exome or -genome sequencing data, and tested ciliogenesis in two affected individuals. The brain malformation comprised posterior predominant lissencephaly and midline crossing defects consisting of absent anterior commissure and a striking W-shaped brainstem malformation caused by small or absent pontine crossing fibers. We discovered heterozygous de novo missense variants or an in-frame deletion involving highly conserved zinc-binding residues within the GAR domain of MACF1 in the first eight subjects. We studied cilium formation and found a higher proportion of mutant cells with short cilia than of control cells with short cilia. A ninth child had similar lissencephaly but only subtle brainstem dysplasia associated with a heterozygous de novo missense variant in the spectrin repeat domain of MACF1. Thus, we report variants of the microtubule-binding GAR domain of MACF1 as the cause of a distinctive and most likely pathognomonic brain malformation. A gain-of-function or dominant-negative mechanism appears likely given that many heterozygous mutations leading to protein truncation are included in the ExAC Browser. However, three de novo variants in MACF1 have been observed in large schizophrenia cohorts.


Assuntos
Orientação de Axônios/genética , Movimento Celular/genética , Sequência Conservada/genética , Proteínas dos Microfilamentos/genética , Mutação/genética , Neurônios/patologia , Zinco/metabolismo , Adolescente , Tronco Encefálico/patologia , Criança , Pré-Escolar , Cílios/genética , Feminino , Humanos , Lisencefalia/genética , Masculino , Microtúbulos/genética , Malformações do Sistema Nervoso/genética
14.
Toxicol Appl Pharmacol ; 426: 115618, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126112

RESUMO

WHO suggests that colon cancer incidences are rising steadily, propelling researchers to search for novel chemotherapeutic options. Metal-based chemotherapy is a potential forte to explore ruthenium-based complexes, exhibiting the capability to influence a variety of cellular targets. We discovered the chemotherapeutic effects of ruthenium-rifampicin complex on HT-29 and HCT-116 human colorectal cell lines and on a chemically developed murine colorectal cancer model. Complex was synthesized and characterized by analytical techniques and evaluation of antioxidant potential along with DNA binding capabilities. The complex minimizes cellular propagation and initiates apoptotic events in the colon cancer cell lines of HT-29 and HCT-116. The results of the in vivo study suggest that the complex has been successful in minimizing the wide spectrum of aberrant crypt foci and hyperplastic lesions, as well as encouraging elevated amounts of CAT, SOD and glutathione. Along with that, p53 could be modulated by the ruthenium-rifampicin complex to interfere with apoptosis in colon carcinoma, initiated by the intrinsic apoptotic trail facilitated through Bcl2 and Bax, thus controlling the Akt/mTOR/VEGF pathway coupled through the WNT/ß-catenin trail. Ruthenium-rifampicin chemotherapy could interrupt, retract or interrupt the progression of colorectal cancer through modifying intrinsic apoptosis including the antiangiogenic pathway, thereby achieving the function of a potential contender in chemotherapy in the near future.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Rifampina/uso terapêutico , Compostos de Rutênio/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Combinação de Medicamentos , Feminino , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Rifampina/farmacologia , Rifampina/toxicidade , Compostos de Rutênio/farmacologia , Compostos de Rutênio/toxicidade , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
J Micromech Microeng ; 31(4)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35592766

RESUMO

Flexible electronics require more compact interconnects for next-generation devices. Polymer devices can be bonded to integrated circuit chips, but combining flexible and rigid substrates poses unique technical challenges. Existing technologies either cannot achieve the density required for modern chips or employ specialized equipment and complex processes to do so. Here, we adapt several approaches to achieve fine-pitch bonding between rigid and flexible substrates including epoxy, ultrasonic wire, and anisotropic conductive film bonding and also introduce a novel technique called polymer ultrasonic on bump (PUB) bonding. Using Parylene C devices and various rigid substrates as our model testbed systems, we investigate these four methods across a range of bond pad size and pitch by measuring yield and resistance and by subjecting devices to thermomechanical reliability tests. We demonstrate that all methods are capable of bonding fine pitch interconnects (100 µm) at low temperature (<100 °C). Additionally, we focus on PUB bonding and join a packaged chip and a bare die to Parylene devices.

16.
Molecules ; 26(21)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34770816

RESUMO

Active carbon-based sorbents are well known and are used in analytical chemistry. Activated carbon fibers (ACFs) are mainly used as abatement systems in industrial emission pollution control. The objective of this study was to extend the use of ACFs in analytical chemistry for the analysis of polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (PCBs), and chlorobenzenes (CBs). For this purpose, the extraction efficiency was evaluated based on the QA/QC criteria defined by EPA/ISO reference methods on 13C-standards recovery rates. The procedures tested were ultrasonic assisted extraction (UAE), Soxhlet extraction (SE), accelerated solvent extraction (ASE), and microwave-assisted extraction (MAE). Each experiment was performed in triplicate to ensure the repeatability of the results, and a second extraction assessed the complete extraction. The comparison of the results of each set of experiments with the minimum requirements of the reference methods for each class of compounds led to SE being chosen as the best technique. SE with toluene resulted in a reduction of time and costs and with respect to the other investigated techniques. The present work demonstrated that ACFs can be used in environmental fields means of both prevention and control (exploiting the adsorbent characteristics) and for analytical purposes (exploiting the desorption) for the described chlorinated classes of pollutants.

17.
Appl Soft Comput ; 103: 107161, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33584158

RESUMO

Most countries are reopening or considering lifting the stringent prevention policies such as lockdowns, consequently, daily coronavirus disease (COVID-19) cases (confirmed, recovered and deaths) are increasing significantly. As of July 25th, there are 16.5 million global cumulative confirmed cases, 9.4 million cumulative recovered cases and 0.65 million deaths. There is a tremendous necessity of supervising and estimating future COVID-19 cases to control the spread and help countries prepare their healthcare systems. In this study, time-series models - Auto-Regressive Integrated Moving Average (ARIMA) and Seasonal Auto-Regressive Integrated Moving Average (SARIMA) are used to forecast the epidemiological trends of the COVID-19 pandemic for top-16 countries where 70%-80% of global cumulative cases are located. Initial combinations of the model parameters were selected using the auto-ARIMA model followed by finding the optimized model parameters based on the best fit between the predictions and test data. Analytical tools Auto-Correlation function (ACF), Partial Auto-Correlation Function (PACF), Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) were used to assess the reliability of the models. Evaluation metrics Mean Absolute Error (MAE), Mean Square Error (MSE), Root Mean Square Error (RMSE) and Mean Absolute Percent Error (MAPE) were used as criteria for selecting the best model. A case study was presented where the statistical methodology was discussed in detail for model selection and the procedure for forecasting the COVID-19 cases of the USA. Best model parameters of ARIMA and SARIMA for each country are selected manually and the optimized parameters are then used to forecast the COVID-19 cases. Forecasted trends for confirmed and recovered cases showed an exponential rise for countries such as the United States, Brazil, South Africa, Colombia, Bangladesh, India, Mexico and Pakistan. Similarly, trends for cumulative deaths showed an exponential rise for countries Brazil, South Africa, Chile, Colombia, Bangladesh, India, Mexico, Iran, Peru, and Russia. SARIMA model predictions are more realistic than that of the ARIMA model predictions confirming the existence of seasonality in COVID-19 data. The results of this study not only shed light on the future trends of the COVID-19 outbreak in top-16 countries but also guide these countries to prepare their health care policies for the ongoing pandemic. The data used in this work is obtained from publicly available John Hopkins University's COVID-19 database.

18.
BMC Cancer ; 20(1): 133, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075595

RESUMO

BACKGROUND: The importance of ACF is not fully explained, however, their number may be a good predictor of synchronous and metachronic adenoma or other polyps whose removal reduces the risk of CRC. Due to the epidemiological and genetic association of ACF with pre-cancer lesions, they may be a potential CRC biomarker. The aim of our study was to show that the number and type of rectal ACF may be a good predictive factor for the presence of polyps located proximally from the splenic flexure and that the type and number of ACF can correlate with the number and specific types of polyps in the large intestine. METHODS: The study included 131 patients who underwent colonoscopy combined with rectal mucosa staining with 0.25% methylene blue. The number of rectal ACF was determined and bioptats were sampled for histopathological examination to assess the type of ACF. Endoscopic ACF assessment criteria given by L. Roncucci were used. The obtained material was subjected to statistical analysis using probability distribution, U-test, t-student test, and chi 2 as well as the Statistica 7.1 software package. RESULTS: The study population was divided into three subgroups according to the number of ACF observed, i.e. ACF < 5, 5-10 and > 10. ACF < 5 were found in 35 patients (29.41%), 5-10 ACF in 70 (58.82%) and ACF > 10 in 14 individuals (11.76%). The study revealed the presence of normal ACF (p = 0.49), hyperplastic ACF (p = 0.34), dysplastic ACF (p = 0.11), and mixed ACF (p = 0.06). A single type of ACF was most commonly observed (n = 88, p = 0.74). In the researched group a larger number of ACF is concurrent with adenomas and hyperplastic polyps. The number of ACF clearly correlates with the dysplasia advancement in the adenoma and the number of polyps found. CONCLUSIONS: Rectal ACF are a useful marker for the presence of cancerous lesions in the proximal and distal sections of the large intestine.


Assuntos
Focos de Criptas Aberrantes/patologia , Adenoma/patologia , Biomarcadores Tumorais/análise , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Intestino Grosso/patologia , Lesões Pré-Cancerosas/patologia , Adenoma/cirurgia , Idoso , Pólipos do Colo/cirurgia , Colonoscopia/métodos , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/cirurgia , Fatores de Risco
19.
Can J Physiol Pharmacol ; 98(3): 147-155, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31614098

RESUMO

This study aimed to investigate the underlying mechanisms in anti-tumorigenesis effects of exercise through evaluation of inflammation and apoptosis. Twenty-four Wistar rats were divided into control, exercise, 1,2-dimethylhydrazine (DMH), and DMH + exercise. After a week, rats in the DMH group were given DMH twice a week for 2 weeks. Animals in the exercise groups performed exercise on a treadmill 5 days/week for 8 weeks. After 8 weeks of training, levels of COX-2, PCNA, Bax, Bcl-2, and procaspase-3/cleaved caspase-3 were assessed. Histological changes, number of aberrant crypt foci (ACF), and serum levels of TNF-α and IL-6 were also analyzed. ACF number was significantly decreased following the exercise program. Protein levels of COX-2 and PCNA and serum levels of IL-6 and TNF-α were significantly elevated in the rats receiving DMH and downregulated after performing the exercise program (P < 0.05). Exercise upregulated apoptosis, which was evident from the increased Bax/Bcl2 ratio, and enhanced the expression levels of activated caspase-3 as compared to the DMH group. The colonic architecture was improved in DMH + exercise. Exercise can effectively attenuate DMH-induced increase of inflammatory markers. Exercise induces apoptosis at the downstream of the inflammatory response. Therefore, exercise may play a role as a moderator of inflammation to exert protective effects against colon cancer.


Assuntos
1,2-Dimetilidrazina/toxicidade , Focos de Criptas Aberrantes/terapia , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Colorretais/terapia , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Condicionamento Físico Animal , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/metabolismo , Focos de Criptas Aberrantes/patologia , Animais , Apoptose , Carcinógenos/toxicidade , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Ratos , Ratos Wistar
20.
Sensors (Basel) ; 20(16)2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764301

RESUMO

This paper presents an experimental evaluation of real-time pedestrian detection algorithms and their tuning using the proposed universal performance index. With this index, the precise choice of various parameters is possible. Moreover, we determined the best resolution of the analysis window, which is much lower than the initial window. By such means, we can speed-up the processing (i.e., reduce the classification time by 74%). There are cases in which we increased both the processing speed and the classification accuracy. We made experiments with various baseline detectors and datasets in order to confirm versatility of the proposed ideas. The analyzed classifiers are those typically applied to detection of pedestrians, namely: aggregated channel feature (ACF), deep convolutional neural network (CNN), and support vector machine (SVM). We used a suite of five precisely chosen night (and day) IR vision datasets.

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