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1.
Neuroimage ; 295: 120650, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38768740

RESUMO

Exploring the relationship between sensory perception and brain responses holds important theoretical and clinical implications. However, commonly used methodologies like correlation analysis performed either intra- or inter- individually often yield inconsistent results across studies, limiting their generalizability. Representational similarity analysis (RSA), a method that assesses the perception-response relationship by calculating the correlation between behavioral and neural patterns, may offer a fresh perspective to reveal novel findings. Here, we delivered a series of graded sensory stimuli of four modalities (i.e., nociceptive somatosensory, non-nociceptive somatosensory, visual, and auditory) to/near the left or right hand of 107 healthy subjects and collected their single-trial perceptual ratings and electroencephalographic (EEG) responses. We examined the relationship between sensory perception and brain responses using within- and between-subject correlation analysis and RSA, and assessed their stability across different numbers of subjects and trials. We found that within-subject and between-subject correlations yielded distinct results: within-subject correlation revealed strong and reliable correlations between perceptual ratings and most brain responses, while between-subject correlation showed weak correlations that were vulnerable to the change of subject number. In addition to verifying the correlation results, RSA revealed some novel findings, i.e., correlations between behavioral and neural patterns were observed in some additional neural responses, such as "γ-ERS" in the visual modality. RSA results were sensitive to the trial number, but not to the subject number, suggesting that consistent results could be obtained for studies with relatively small sample sizes. In conclusion, our study provides a novel perspective on establishing the relationship between behavior and brain activity, emphasizing that RSA holds promise as a method for exploring this pattern relationship in future research.


Assuntos
Eletroencefalografia , Humanos , Masculino , Feminino , Eletroencefalografia/métodos , Adulto , Adulto Jovem , Encéfalo/fisiologia , Percepção Visual/fisiologia , Percepção Auditiva/fisiologia
2.
Chemphyschem ; 25(11): e202400008, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38514394

RESUMO

Structure-guided engineering of a CHMO from Amycolatopsis methanolica (AmCHMO) was performed for asymmetric sulfoxidation activity and stereoselectivity toward omeprazole sulfide. Initially, combinatorial active-site saturation test (CASTing) and iteratively saturation mutagenesis (ISM) were performed on 5 residues at the "bottleneck" of substrate tunnel, and MT3 was successfully obtained with a specific activity of 46.19 U/g and R-stereoselectivity of 99 % toward OPS. Then, 4 key mutations affecting the stereoselectivity were identified through multiple rounds of ISM on residues at the substrate binding pocket region, resulting MT8 with an inversed stereoselectivity from 99 % (R) to 97 % (S). MT8 has a greatly compromised specific activity of 0.08 U/g. By introducing additional beneficial mutations, MT11 was constructed with significantly increased specific activity of 2.29 U/g and stereoselectivity of 97 % (S). Enlarged substrate tunnel is critical to the expanded substrate spectrum of AmCHMO, while reshaping of substrate binding pocket is important for stereoselective inversion. Based on MD simulation, pre-reaction states of MT3-OPSproR, MT8-OPSproS, and MT11-OPSproS were calculated to be 45.56 %, 17.94 %, and 28.65 % respectively, which further confirm the experimental data on activity and stereoselectivity. Our results pave the way for engineering distinct activity and stereoselectivity of BVMOs toward bulky prazole thioethers.


Assuntos
Omeprazol , Oxigenases , Estereoisomerismo , Oxigenases/metabolismo , Oxigenases/química , Oxigenases/genética , Omeprazol/química , Omeprazol/metabolismo , Especificidade por Substrato , Actinomycetales/enzimologia , Actinomycetales/metabolismo , Domínio Catalítico
3.
Cereb Cortex ; 33(9): 5323-5335, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36320161

RESUMO

When anticipating future losses, people respond by exhibiting 1 of 2 starkly distinct behavioral decision patterns: the dread of future losses (DFL) and the preference of future losses (vs. immediate losses). Yet, how to accurately discriminate between those who exhibit dread vs. preference and uncover the potential neurobiological substrates underlying these 2 groups remain understudied. To address this, we designed a novel experimental task in which the DFL group was defined as selecting immediate-loss options >50% in the trials with approximate subjective value in immediate and delayed options (n = 16), otherwise coding as the preference of future losses (PFL). At the behavioral level, DFL exhibited higher weight for delayed losses than immediate losses via the logistic regression model. At the neural level, DFL manifested hypoactivations on subjective valuations of delayed losses, atypical brain pattern when choosing immediate-loss options, and decreased functional coupling between the valuation and choice-systems when making decisions related to immediate-loss alternatives compared with PFL. Moreover, both these brain activations subserving distinct decision processes and their interactions predicted individual decisions and behavioral preferences. Furthermore, morphological analysis also revealed decreased right precuneus volume in DFL compared with PFL, and brain activations related to valuation and choice process mediated the associations between this region volume and behavioral performances. Taken together, these findings help to clarify potential cognitive and neural mechanisms underlying the DFL and provide a clear discrimination strategy.


Assuntos
Encéfalo , Tomada de Decisões , Humanos , Mapeamento Encefálico , Recompensa
4.
Molecules ; 29(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39274952

RESUMO

The construction of anatase/rutile heterojunctions in TiO2 is an effective way of improving the CO2 photoreduction activity. Yet, the origin of the superior photocatalytic performance is still unclear. To solve this issue, the band edges between anatase and rutile phases were theoretically determined based on the three-phase atomic model of (112)A/II/(101)R, and simultaneously the CO2 reduction processes were meticulously investigated. Our calculations show that photogenerated holes can move readily from anatase to rutile via the thin intermediated II phase, while photoelectrons flowing in the opposite direction may be impeded due to the electron trapping sites at the II phase. However, the large potential drop across the anatase/rutile interface and the strong built-in electric field can provide an effective driving force for photoelectrons' migration to anatase. In addition, the II phase can better enhance the solar light utilization of (112)A/(100)II, including a wide light response range and an intensive optical absorption coefficient. Meanwhile, the mixed-phase TiO2 possesses negligible hydrogenation energy (CO2 to COOH*) and lower rate-limiting energy (HCOOH* to HCO*), which greatly facilitate CH3OH generation. The efficient charge separation, strengthened light absorption, and facile CO2 reduction successfully demonstrate that the anatase/rutile mixed-phase TiO2 is an efficient photocatalyst utilized for CO2 conversion.

5.
J Sci Food Agric ; 104(4): 2449-2457, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37961839

RESUMO

BACKGROUND: The shortage of water resources and the increase of greenhouse gas emissions from soil seriously restrict the sustainable development of agriculture. Under the premise of ensuring a stable yield of winter wheat through a reasonable irrigation scenario, identifying a suitable straw returning method will have a positive effect on agricultural carbon sequestration and emission reduction in North China Plain. RESULTS: Straw burying (SR) and straw mulching (SM) were adopted based on traditional tillage under in the winter wheat growing season of 2020-2021 and 2021-2022. Three irrigation scenarios were used for each straw returning method: no irrigation (I0), irrigation 60 mm at jointing stage (I1), and irrigation of 60 mm each at the jointing and heading stages (I2). Soil moisture, soil respiration rate, cumulative soil CO2 emissions, yield, water use efficiency (WUE) and soil CO2 emission efficiency (CEE) were mainly studied. The results showed that, compared to SM, SR improved the utilization of soil water and enhanced soil carbon sequestration. SR reduced soil respiration rate and cumulative soil CO2 emissions in two winter wheat growing seasons, and increased yield by increasing spike numbers. In addition, with an increase in the amount of irrigation, soil CO2 emissions and yield increased. Under SR-I1 treatment, WUE and CEE were the highest. SR-I1 increases crop yields at the same time as reducing soil CO2 emissions. CONCLUSION: The combination of SR and irrigation 60 mm at jointing stage is a suitable straw returning irrigation scenario, which can improve water use and reduce soil CO2 emission in NCP. © 2023 Society of Chemical Industry.


Assuntos
Solo , Triticum , Estações do Ano , Dióxido de Carbono/análise , Água , Carbono , Agricultura/métodos , China
6.
Water Sci Technol ; 88(11): 2849-2861, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38096073

RESUMO

Capacitive deionization (CDI) is considered a promising technology for desalination of sea or brackish water. In this study, a ZnS/g-C3N4 composite was synthesized through a one-step high-temperature method and used as the main material to fabricate CDI electrodes. The results of SEM and TEM showed that spherical-like nanoparticles of ZnS were uniformly distributed on the g-C3N4 sheet. The g-C3N4 phase facilitates the ZnS particles precipitate and restrain their agglomeration, which contributes to a high specific surface area of ZnS. Furthermore, the electrochemical test results indicated that ZnS/g-C3N4 composite had a good capacitance characteristic, low resistance, and high electrochemical stability. Finally, the desalinization performance of the ZnS/g-C3N4 composite electrodes was tested in traditional mode and membrane capacitive deionization (MCDI) mode. The results showed that ZnS/g-C3N4//ZnS/g-C3N4 (MCDI) exhibited an optimal desalination capacity. The adsorption amount was 27.65, 50.26, and 65.34 mg/g for NaCl initial concentration of 200, 400, and 600 mg/L, respectively, with the voltage of 1.2 V and flow rate of 5 mL/min. Increasing initial concentration enhanced the conductivity and ion migration rate so as to increase the NaCl adsorption amount. ZnS/g-C3N4 composite can be used as potential electrode material for high performance of MCDI.


Assuntos
Cloreto de Sódio , Purificação da Água , Purificação da Água/métodos , Condutividade Elétrica , Águas Salinas , Eletrodos
7.
Hum Brain Mapp ; 42(11): 3450-3469, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33934449

RESUMO

Numerous studies have examined the neural substrates of intertemporal decision-making, but few have systematically investigated separate neural representations of the two attributes of future rewards (i.e., the amount of the reward and the delay time). More importantly, no study has used the novel analytical method of representational connectivity analysis (RCA) to map the two dimensions' functional brain networks at the level of multivariate neural representations. This study independently manipulated the amount and delay time of rewards during an intertemporal decision task. Both univariate and multivariate pattern analyses showed that brain activity in the dorsomedial prefrontal cortex (DMPFC) and lateral frontal pole cortex (LFPC) was modulated by the amount of rewards, whereas brain activity in the DMPFC and dorsolateral prefrontal cortex (DLPFC) was modulated by the length of delay. Moreover, representational similarity analysis (RSA) revealed that even for the regions of the DMPFC that overlapped between the two dimensions, they manifested distinct neural activity patterns. In terms of individual differences, those with large delay discounting rates (k) showed greater DMPFC and LFPC activity as the amount of rewards increased but showed lower DMPFC and DLPFC activity as the delay time increased. Lastly, RCA suggested that the topological metrics (i.e., global and local efficiency) of the functional connectome subserving the delay time dimension inversely predicted individual discounting rate. These findings provide novel insights into neural representations of the two attributes in intertemporal decisions, and offer a new approach to construct task-based functional brain networks whose topological properties are related to impulsivity.


Assuntos
Mapeamento Encefálico , Desvalorização pelo Atraso/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Recompensa , Adulto , Córtex Pré-Frontal Dorsolateral/diagnóstico por imagem , Córtex Pré-Frontal Dorsolateral/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Fatores de Tempo , Adulto Jovem
8.
Nano Lett ; 20(1): 644-651, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31790260

RESUMO

Solar-blind deep ultraviolet photodetectors (DUVPDs) based on conventional inorganic ultrawide bandgap semiconductors (UWBS) have shown promising application in various civil and military fields and yet they can hardly be used in wearable optoelectronic devices and systems for lack of mechanical flexibility. In this study, we report a non-UWBS solar-blind DUVPD by designing ultrathin polymer nanofibrils with a virtual ultrawide bandgap, which was obtained by grafting P3HT with PHA via a polymerization process. Optoelectronic analysis reveals that the P3HT-b-PHA nanofibrils are sensitive to DUV light with a wavelength of 254 nm but are virtually blind to both 365 nm and other visible light illuminations. The responsivity is 120 A/W with an external quantum efficiency of up to 49700%, implying a large photoconductive gain in the photoresponse process. The observed solar-blind DUV photoresponse is associated with the resonant mode due to the leakage mode of the ultrathin polymer nanofibrils. Moreover, a flexible image sensor composed of 10 × 10 pixels can also be fabricated to illustrate their capability for image sensing application. These results signify that the present ultrathin P3HT-b-PHA nanofibrils are promising building blocks for assembly of low-cost, flexible, and high-performance solar-blind DUVPDs.

9.
Entropy (Basel) ; 23(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34573731

RESUMO

Bubble coalescence and breakup play important roles in physical-chemical processes and bubbles are treated in two groups in the interfacial area transport equation (IATE). This paper presents a review of IATE for bubble coalescence and breakup to model five bubble interaction mechanisms: bubble coalescence due to random collision, bubble coalescence due to wake entrainment, bubble breakup due to turbulent impact, bubble breakup due to shearing-off, and bubble breakup due to surface instability. In bubble coalescence, bubble size, velocity and collision frequency are dominant. In bubble breakup, the influence of viscous shear, shearing-off, and surface instability are neglected, and their corresponding theory and modelling are rare in the literature. Furthermore, combining turbulent kinetic energy and inertial force together is the best choice for the bubble breakup criterion. The reviewed one-group constitutive models include the one developed by Wu et al., Ishii and Kim, Hibiki and Ishii, Yao and Morel, and Nguyen et al. To extend the IATE prediction capability beyond bubbly flow, two-group IATE is needed and its performance is strongly dependent on the channel size and geometry. Therefore, constitutive models for two-group IATE in a three-type channel (i.e., narrow confined channel, round pipe and relatively larger pipe) are summarized. Although great progress in extending the IATE beyond churn-turbulent flow to churn-annual flow was made, there are still some issues in their modelling and experiments due to the highly distorted interface measurement. Regarded as the challenges to be addressed in the further study, some limitations of IATE general applicability and the directions for future development are highlighted.

10.
Dermatol Ther ; 33(4): e13690, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32468693

RESUMO

The aim of this study was to explore the main factors affecting the occurrence of dandruff in healthy people (nondisease-induced scalp desquamation). This study analyzed the fungal microbial diversity of the scalp in Chinese teenage volunteers and measured scalp sebum secretion, the scalp pH value, and scalp transepidermal water loss. The amount and size of dandruff were measured, and the main factors that influence dandruff in the normal population were identified using principal component analysis. The results showed that an increase in Malassezia restricta led to an increased amount of dandruff in the mild and moderate groups. Conversely, this was not found for individuals in the severe group, whose dandruff symptoms were influenced by scalp barrier function. In terms of dandruff area grouping, the pH value and the amount of sebum secretion were the main factors, with the barrier function and microbial diversity being secondary factors. Dandruff cosmetics should emphasize different treatments for different types of dandruff to achieve better antidandruff effects. The results of this study provide a new theoretical basis for the development of multiple targets for antidandruff agents aimed at the normal population.


Assuntos
Caspa , Malassezia , Adolescente , Caspa/diagnóstico , Análise Fatorial , Humanos , Couro Cabeludo
11.
Cytokine ; 119: 175-181, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30952064

RESUMO

The maturation state of dendritic cell (DC) plays an important role in immune activities. Previously we had found that NF-κB (p65) pathway could promote DC maturation and subsequent immune effects. But the upstream mechanism of this pathway was still unclear. Extracellular adenosine triphosphate (ATP) activating its receptor P2X7R has recently been considered as the fourth signal to activate T lymphocytes. Here we aimed to find out the connection between P2X7R and NF-κB (p65) pathway in DC maturation. Results showed that the expression of P2X7R and the intracellular ATP levels were increased along with the maturation of DC. P2X7R agonist stimulated the morphological changes of DCs into the appearance of mature DCs, and promoted the expression of NF-κB (p65), as well as the release of IFN-γ and IL-12. Whereas, P2X7R inhibitor had the opposite influences. Co-immunoprecipitation assay confirmed the binding of P2X7R and NF-κB (p65). Our study suggested that extracellular ATP could promote DC maturation and release of inflammatory cytokines through the binding of P2X7R and NF-κB (p65). This is the first study to show the P2X7R-NF-κB (p65) pathway in DC. Interference with this pathway may be able to regulate immune responses in areas like infectious diseases, inflammation, transplantation, tumor and autoimmune diseases. In addition, intracellular ATP level could be a new indicator of the maturation state of DC.


Assuntos
Trifosfato de Adenosina/metabolismo , Medula Óssea/metabolismo , Células Dendríticas/metabolismo , Receptores Purinérgicos P2/metabolismo , Transdução de Sinais/fisiologia , Fator de Transcrição RelA/metabolismo , Animais , Diferenciação Celular/fisiologia , Citocinas/metabolismo , Feminino , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Linfócitos T/metabolismo
12.
Nanoscale ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39376165

RESUMO

Silicon materials are irreplaceable in the modern information society because of their rich resource, low price, and mature manufacturing technology for optoelectronics. However, improving the responsivity and response speed of silicon-based photodetectors is still a challenge. Here, a double-heterojunction photodetector (PD) by coupling two-dimensional PtSe2 thin film with a graphene/silicon Schottky junction is proposed. The introduction of PtSe2 enhances the built-in electric field of the device, thus suppressing the dark-state current and promoting the separation of photogenerated electron-hole pairs. Under 808 nm laser illumination, the PtSe2/graphene/Si PD exhibits an optimal responsivity, specific detectivity, and response speed of 0.81 A W-1, 1.24 × 109 Jones, and 43.6/51.2 µs, respectively. These performance indexes are obviously better than the corresponding graphene/Si device. Furthermore, the PtSe2/graphene/Si PD has good environmental durability and photoresponse ability from the ultraviolet to near-infrared. This work will provide new possibilities for designing novel silicon-based photodetection devices with high performance and fast response.

13.
Biotechnol J ; 19(1): e2300483, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38041508

RESUMO

Rhodotorula toruloides can utilize crude glycerol as the low-cost carbon source for lipid production, but its growth is subjected to inhibition by methanol in crude glycerol. Here, transcriptome profiling demonstrated that 1004 genes were significantly regulated in the strain R. toruloides TO2 under methanol stress. Methanol impaired the function of membrane transport and subsequently weakened the utilization of glycerol, activities of the primary metabolism and functions of nucleus and ribosome. Afterwards the tolerance of TO2 to methanol was improved by using two-round adaptive laboratory evolution (ALE). The final strain M2-ale had tolerance up to 3.5% of methanol. 1 H NMR-based metabolome analysis indicated that ALE not only improved the tolerance of M2-ale to methanol but also tuned the carbon flux towards the biosynthesis of glycerolipid-related metabolites. The biomass and lipid titer of M2-ale reached 14.63 ± 0.45 g L-1 and 7.06 ± 0.44 g L-1 at 96 h in the crude glycerol medium, which increased up to 17.69% and 31.39%, respectively, comparing with TO2. Afterwards, an effective method for cell lysis was developed by combining sonication and enzymatic hydrolysis (So-EnH). The lytic effect of So-EnH was validated by using confocal imaging and flow cytometry. At last, lipid recovery rate reached 95.4 ± 2.7% at the optimized condition.


Assuntos
Glicerol , Rhodotorula , Glicerol/metabolismo , Metanol/metabolismo , Rhodotorula/genética , Rhodotorula/metabolismo , Biomassa , Lipídeos
14.
Environ Sci Pollut Res Int ; 31(11): 16274-16290, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342833

RESUMO

Electric arc furnace dust (EAFD) is a hazardous by-product of steel production. As global steel output increases, substantial amounts of EAFD are produced, which causes significant environmental issues. EAFD contains quantities of Fe and Zn, which could be reused as raw materials in the steelmaking process. However, zinc oxides can be reduced and vaporized during this process, forming zinc vapor that contaminates equipment surfaces and causes damage. Consequently, various pyrometallurgical methods have been proposed for zinc removal from EAFD. Due to the extensive usage of carbonaceous materials, these methods contribute to significant CO2, raising concerns about greenhouse gas emissions. Microwave heating offers an efficient, energy-saving, and environmentally friendly alternative to pyrometallurgical approaches. EAFD can generate heat under microwave irradiation without carbon addition, which means the CO2 emissions can be reduced by replacing the reductant in the microwave heating process. Furthermore, microwaves enhance zinc removal reactions to a certain extent, resulting in higher efficiency. Thus, employing microwave heating for EAFD processing has significant potential for future development. This paper reviews recent research on using microwave heating for zinc removal from EAFD, focusing on the heating behavior of EAFD in microwaves and the mechanisms of zinc removal. This review will be crucial for researchers working on processing EAFD using microwave heating and could help guide the development of more sustainable and efficient methods.


Assuntos
Poeira , Zinco , Poeira/análise , Micro-Ondas , Dióxido de Carbono , Calefação , Aço
15.
Adv Sci (Weinh) ; : e2407493, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287113

RESUMO

Triple negative breast cancer (TNBC) is the most aggressive subtype in breast tumors. When re-analyzing TCGA breast cancer dataset, we found cell adhesion molecules are highly enriched in differentially expressed genes in TNBC samples, among which Focal Adhesion Kinase (FAK) is most significantly associated with poor survival of TNBC patients. FAK is precisely modulated in the focal adhesion dynamics. To investigate whether lncRNAs regulate FAK signaling, we performed RNA immunoprecipitation sequencing and found FAISL (FAK Interacting and Stabilizing LncRNA) abundantly enriched in FAK-interacting lncRNAs and frequently overexpressed in TCGA TNBC tissues. FAISL promotes TNBC cell adhesion, cytoskeleton spreading, proliferation, and anchor-independent survival. FAISL doesn't affect FAK mRNA but positively regulates FAK protein level by blocking Calpain 2-mediated proteolysis. FAISL interacts with the C-terminus domain of FAK, whereby masks the binding site of Calpain 2 and prevents FAK cleavage. High level of FAISL correlates with FAK expression in tumor tissues and poor prognosis of TNBC patients. A siRNA delivery system targeting FAISL using reduction-responsive nanoparticles effectively inhibits tumor growth and metastasis in TNBC mouse models. Together, these findings uncover a lncRNA-mediated mechanism of regulating FAK proteolysis in the TNBC progression, and highlight the potential of targeting lncRNA FAISL for TNBC treatment.

16.
Adv Sci (Weinh) ; 11(19): e2309481, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477429

RESUMO

Diabetic ketoacidosis (DKA) is a life-threatening acute complication of diabetes characterized by the accumulation of ketone bodies in the blood. Breath acetone, a ketone, directly correlates with blood ketones. Therefore, monitoring breath acetone can significantly enhance the safety and efficacy of diabetes care. In this work, the design and fabrication of an InP/Pt/chitosan nanowire array-based chemiresistive acetone sensor is reported. By incorporation of chitosan as a surface-functional layer and a Pt Schottky contact for efficient charge transfer processes and photovoltaic effect, self-powered, highly selective acetone sensing is achieved. The sensor has exhibited an ultra-wide acetone detection range from sub-ppb to >100 000 ppm level at room temperature, covering those in the exhaled breath from healthy individuals (300-800 ppb) to people at high risk of DKA (>75 ppm). The nanowire sensor has also been successfully integrated into a handheld breath testing prototype, the Ketowhistle, which can successfully detect different ranges of acetone concentrations in simulated breath samples. The Ketowhistle demonstrates the immediate potential for non-invasive ketone monitoring for people living with diabetes, in particular for DKA prevention.


Assuntos
Acetona , Testes Respiratórios , Nanofios , Acetona/análise , Humanos , Testes Respiratórios/métodos , Testes Respiratórios/instrumentação , Cetoacidose Diabética/diagnóstico , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Quitosana/química , Desenho de Equipamento , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/sangue
17.
Ultrasonics ; 135: 107129, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37562285

RESUMO

Medium carbon steel is an excellent carbon structural steel, and is one of the most common materials for metal cutting. Little research has been done on the microstructural changes induced by thermal-force coupling. In this paper, a finite element simulation method based on the improved J-C model is used to predict the grain size, microstructure change depth and surface hardness of medium carbon steel surface induced by heat-assisted 3D-UVAT are studied. The numerical simulation results are compared with the experimental results, and the significant influence of turning conditions on them is analyzed. The results show that heat-assisted 3D-UVAT lowered the grain size of machined induced deformation zone. Numerical model foresees this case with a mean error of 9.4%. Microstructure and hardness measurements under different turning conditions show that the turning speed and feed rate contribute significantly to grain size and grain refinement layer depth in the area being machined.

18.
Gen Psychiatr ; 36(6): e101164, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38143714

RESUMO

Introduction: Virtual reality (VR) and transcutaneous electrical nerve stimulation (TENS) have emerged as effective interventions for pain reduction. However, their standalone applications often yield limited analgesic effects, particularly in certain painful conditions. Aims: Our hypothesis was that the combination of VR with TENS in a synchronous manner could produce the best analgesic effect among the four experimental conditions. Methods: To address this challenge, we proposed a novel pain modulation strategy that synchronously combines VR and TENS, aiming to capitalise on both techniques' complementary pain modulation mechanisms. Thirty-two healthy subjects participated in the study and underwent three types of interventions: VR alone, a combination of VR with conventional TENS, and a combination of VR with synchronous TENS. Additionally, a control condition with no intervention was included. Perceived pain intensity, pain unpleasantness, positive and negative affect scores, and electroencephalographic (EEG) data were collected before and after the interventions. To delve into the potential moderating role of pain intensity on the analgesic efficacy of VR combined with synchronous TENS, we incorporated two distinct levels of painful stimuli: one representing mild to moderate pain (ie, low pain) and the other representing moderate to severe pain (ie, high pain). Results: Our findings revealed that both combination interventions exhibited superior analgesic effects compared with the VR-alone intervention when exposed to low and high pain stimuli. Notably, the combination of VR with synchronous TENS demonstrated greater analgesic efficacy than the combination of VR with conventional TENS. EEG data further supported these results, indicating that both combination interventions elicited a greater reduction in event-related potential magnitude compared with the VR-alone intervention during exposure to low and high pain stimuli. Moreover, the synchronous combination intervention induced a more significant reduction in N2 amplitude than the VR-alone intervention during exposure to low pain stimuli. No significant differences in EEG response changes were detected between the two combination interventions. Both combination interventions resulted in a greater reduction in negative affect compared with the VR-alone intervention. Conclusions: Altogether, our study highlights the effectiveness of the synchronous combination of VR and TENS in enhancing pain modulation. These findings offer valuable insights for developing innovative pain treatments, emphasising the importance of tailored and multifaceted therapeutic approaches for various painful conditions.

19.
Adv Mater ; 35(12): e2207199, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36502280

RESUMO

The fast development of the Internet of Things (IoT) has driven an increasing consumer demand for self-powered gas sensors for real-time data collection and autonomous responses in industries such as environmental monitoring, workplace safety, smart cities, and personal healthcare. Despite intensive research and rapid progress in the field, most reported self-powered devices, specifically NO2 sensors for air pollution monitoring, have limited sensitivity, selectivity, and scalability. Here, a novel photovoltaic self-powered NO2 sensor is demonstrated based on axial p-i-n homojunction InP nanowire (NW) arrays, that overcome these limitations. The optimized innovative InP NW array device is designed by numerical simulation for insights into sensing mechanisms and performance enhancement. Without a power source, this InP NW sensor achieves an 84% sensing response to 1 ppm NO2 and records a limit of detection down to the sub-ppb level, with little dependence on the incident light intensity, even under <5% of 1 sun illumination. Based on this great environmental fidelity, the sensor is integrated into a commercial microchip interface to evaluate its performance in the context of dynamic environmental monitoring of motor vehicle exhaust. The results show that compound semiconductor nanowires can form promising self-powered sensing platforms suitable for future mega-scale IoT systems.

20.
Soc Cogn Affect Neurosci ; 18(1)2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35856605

RESUMO

Greed personality trait (GPT), characterized by the desire to acquire more and the dissatisfaction of never having enough, has been hypothesized to link with negative emotion/affect characteristics and aggressive behaviors. To describe its emotion-related features, we utilized a series of scales to measure corresponding emotion/affect and aggression (n = 411) and collected their neuroimaging data (n = 330) to explore underlying morphological substrates. Correlational analyses revealed that greedy individuals show more negative symptoms (e.g. depression, loss of interest, negative affect), lower psychological well-being and more aggression. Mediation analyses further demonstrated that negative symptoms and psychological well-being mediated greedy individuals' aggression. Moreover, exploratory factor analysis extracted factor scores across three factors (negative psychopathology, happiness, and motivation) from the measures scales. Negative psychopathology and happiness remained robust mediators. Importantly, these findings were replicated in an independent sample (n = 68). Voxel-based morphometry analysis also revealed that gray matter volumes (GMVs) in the prefrontal-parietal-occipital system were associated with negative psychopathology and happiness, and GMVs in the frontal pole and middle frontal cortex mediated the relationships between GPT and aggressions. These findings provide novel insights into the negative characteristics of dispositional greed, and suggest their mediating roles on greedy individuals' aggression and underlying neuroanatomical substrates.


Assuntos
Transtornos Mentais , Personalidade , Humanos , Emoções , Córtex Cerebral , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética
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