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1.
J Am Chem Soc ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39257223

RESUMEN

Rational regulation of the electrochemical CO2 reduction reaction (CO2RR) pathway to produce desired products is particularly interesting, yet designing economical and robust catalysts is crucial. Here, we report an antimony-modified copper (CuSb) catalyst capable of selectively producing both CO and multicarbon (C2+) products in the CO2RR. At a current density of 0.3 A/cm2, the faradaic efficiency (FE) of CO was as high as 98.2% with a potential of -0.6 V vs reversible hydrogen electrode (RHE). When the current density increased to 1.1 A/cm2 at -1.1 V vs RHE, the primary products shifted to C2+ compounds with a FE of 75.6%. Experimental and theoretical studies indicate that tuning the potential could manipulate the oxygen species on the CuSb surface, which determined the product selectivity in the CO2RR. At a more positive potential, the existence of oxygen species facilitates the potential-limiting step involving *COOH formation and reduces the adsorption of *CO intermediates, thereby promoting CO production. At a more negative potential, the localized high CO concentration coupled with the enhanced adsorption of *CO intermediates due to Sb incorporation facilitates C-C coupling and deep hydrogenation processes, resulting in an increased C2+ selectivity.

2.
Nat Mater ; 22(12): 1463-1469, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37828101

RESUMEN

Twist angle between two-dimensional layers is a critical parameter that determines their interfacial properties, such as moiré excitons and interfacial ferro-electricity. To achieve better control over these properties for fundamental studies and various applications, considerable efforts have been made to manipulate twist angle. However, due to mechanical limitations and the inevitable formation of incommensurate regions, there remains a challenge in attaining perfect alignment of crystalline orientation. Here we report a thermally induced atomic reconstruction of randomly stacked transition metal dichalcogenide multilayers into fully commensurate heterostructures with zero twist angle by encapsulation annealing, regardless of twist angles of as-stacked samples and lattice mismatches. We also demonstrate the selective formation of R- and H-type fully commensurate phases with a seamless lateral junction using chemical vapour-deposited transition metal dichalcogenides. The resulting fully commensurate phases exhibit strong photoluminescence enhancement of the interlayer excitons, even at room temperature, due to their commensurate structure with aligned momentum coordinates. Our work not only demonstrates a way to fabricate zero-twisted, two-dimensional bilayers with R- and H-type configurations, but also provides a platform for studying their unexplored properties.

3.
Chemistry ; 30(3): e202303316, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37926692

RESUMEN

Balgacyclamide A-C are a family of cyanobactin natural products isolated from freshwater cyanobacteria Microcystis aeruginosa. These macrocyclic peptides are characterized by their oxazoline-thiazole core, their 7 or 8 stereocenters, and their antiparasitic activities. Balgacyclamide B is known for its activity towards Plasmodium falciparum chloroquine-resistant strain K1, Trypanosoma brucei rhodesiense, and Leishmania donovani. In this report, the first total synthesis of Balgacyclamide B is described in a 17-steps pathway and a 2 % overall yield. The synthetic pathway toward balgacyclamide B can be adapted for the future syntheses of balgacyclamide A and C. In addition, a brief history background of oxazolines syntheses is shown to emphasize the importance of the cyclization conditions used to interconvert or retain configuration of ß-hydroxy amides via dehydrative cyclization.


Asunto(s)
Antiparasitarios , Leishmania donovani , Péptidos Cíclicos , Pruebas de Sensibilidad Parasitaria , Trypanosoma brucei rhodesiense , Plasmodium falciparum
4.
Nano Lett ; 23(2): 677-684, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36648125

RESUMEN

Understanding the phase transition mechanisms in two-dimensional (2D) materials is a key to precisely tailor their properties at the nanoscale. Molybdenum ditelluride (MoTe2) exhibits multiple phases at room temperature, making it a promising candidate for phase-change applications. Here, we fabricate lateral 2H-Td interfaces with laser irradiation and probe their phase transitions from micro- to atomic scales with in situ heating in the transmission electron microscope (TEM). By encapsulating the MoTe2 with graphene protection layers, we create an in situ reaction cell compatible with atomic resolution imaging. We find that the Td-to-2H phase transition initiates at phase boundaries at low temperatures (200-225 °C) and propagates anisotropically along the b-axis in a layer-by-layer fashion. We also demonstrate a fully reversible 2H-Td-2H phase transition cycle, which generates a coherent 2H lattice containing inversion domain boundaries. Our results provide insights on fabricating 2D heterophase devices with atomically sharp and coherent interfaces.

5.
Int Heart J ; 65(4): 770-774, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39010227

RESUMEN

The clinical manifestations of licorice-induced pseudoaldosteronism include muscle weakness, periodic paralysis, hypokalemia, and hypertension. Excessive licorice consumption can lead to adverse reactions affecting multiple systems, including the endocrine, cardiovascular, nervous, digestive, and immune systems. Although licorice is a frequently used Chinese herbal medicine, life-threatening adverse reactions have been reported among its users. This article presents a case of severe hypokalemia, torsade de pointes, severe hypertension, and exacerbation of manic symptoms resulting from an overdose of compound licorice tablets. This study aimed to enhance the understanding of the causes of hypokalemia and raise awareness on the potentially fatal adverse reactions associated with licorice drugs.


Asunto(s)
Glycyrrhiza , Hipopotasemia , Torsades de Pointes , Humanos , Glycyrrhiza/efectos adversos , Torsades de Pointes/inducido químicamente , Torsades de Pointes/diagnóstico , Hipopotasemia/inducido químicamente , Masculino , Electrocardiografía , Hipertensión/tratamiento farmacológico , Comprimidos , Medicamentos Herbarios Chinos/efectos adversos , Persona de Mediana Edad
6.
J Cardiovasc Pharmacol ; 81(6): 423-433, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36888974

RESUMEN

ABSTRACT: Epidemic of obesity accelerates the increase in the number of patients with obesity cardiomyopathy. Thioredoxin interacting protein (TXNIP) has been implicated in the pathogenesis of multiple cardiovascular diseases. However, its specific role in obesity cardiomyopathy is still not well understood. Here, we evaluated the role of TXNIP in obesity-induced cardiomyopathy by feeding wild-type and txnip gene knockout mice with either normal diet or high-fat diet (HFD) for 24 weeks. Our results suggested that TXNIP deficiency improved mitochondrial dysfunction via reversing the shift from mitochondrial fusion to fission in the context of chronic HFD feeding, thus promoting cardiac fatty acid oxidation to alleviate chronic HFD-induced lipid accumulation in the heart, and thereby ameliorating the cardiac function in obese mice. Our work provides a theoretical basis for TXNIP exerting as a potential therapeutic target for the interventions of obesity cardiomyopathy.


Asunto(s)
Cardiomiopatías , Dieta Alta en Grasa , Ratones , Animales , Técnicas de Inactivación de Genes , Dieta Alta en Grasa/efectos adversos , Ratones Noqueados , Cardiomiopatías/genética , Cardiomiopatías/prevención & control , Obesidad/genética , Obesidad/metabolismo , Ácidos Grasos/metabolismo , Mitocondrias/metabolismo , Ratones Endogámicos C57BL , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
7.
Acta Biochim Biophys Sin (Shanghai) ; 55(12): 1950-1960, 2023 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-37850269

RESUMEN

Myocardial infarction (MI) results in high mortality. The size of fibrotic scar tissue following MI is an independent predictor of MI outcomes. Thioredoxin-interacting protein (TXNIP) is involved in various fibrotic diseases. Its role in post-MI cardiac fibrosis, however, remains poorly understood. In the present study, we investigate the biological role of TXNIP in post-MI cardiac fibrosis and the underlying mechanism using mouse MI models of the wild-type (WT), Txnip-knockout ( Txnip-KO) type and Txnip-knock-in ( Txnip-KI) type. After MI, the animals present with significantly upregulated TXNIP levels, and their fibrotic areas are remarkably expanded with noticeably impaired cardiac function. These changes are further aggravated under Txnip-KI conditions but are ameliorated in Txnip-KO animals. MI also leads to increased protein levels of the fibrosis indices Collagen I, Collagen III, actin alpha 2 (ACTA2), and connective tissue growth factor (CTGF). The Txnip-KI group exhibits the highest levels of these proteins, while the lowest levels are observed in the Txnip-KO mice. Furthermore, Txnip-KI significantly upregulates the levels of transforming growth factor (TGF)B1, p-Smad3, NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), Cleaved Caspase-1, and interleukin (IL)1B after MI, but these effects are markedly offset by Txnip-KO. In addition, after MI, the Smad7 level significantly decreases, particularly in the Txnip-KI mice. TXNIP may aggravate the progression of post-MI fibrosis and cardiac dysfunction by activating the NLRP3 inflammasome, followed by IL1B generation and then the enhancement of the TGFB1/Smad3 pathway. As such, TXNIP might serve as a novel potential therapeutic target for the treatment of post-MI cardiac fibrosis.


Asunto(s)
Inflamasomas , Infarto del Miocardio , Animales , Ratones , Colágeno , Fibrosis , Inflamasomas/metabolismo , Ratones Endogámicos NOD , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
8.
Pestic Biochem Physiol ; 190: 105337, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36740331

RESUMEN

Precocene I is a juvenile hormone antagonist that needs to be activated via oxidative biotransformation catalyzed by cytochrome P450 (CYP). NADPH-cytochrome P450 reductase (CPR) supplies CYP with electrons in the oxidation-reduction process; however, its functional role in the activation of precocene I remains unexplored. Here, the representative characteristics of CPRs were analyzed in the CPR gene of Locusta migratoria (LmCPR), the result of model docking indicated that the hydrogen bonds were formed between reduced nicotinamide adenine dinucleotide phosphate (NADPH), flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN) and NADPH-, FAD-, FMN-domains of LmCPR, respectively. Treating the fourth-instar nymphs with precocene I decreased the juvenile hormone titers of nymphs to 0.55-fold of that in acetone-treated controls, and extended the interval time between fourth- and fifth-instar nymphs. 68.75% of the treated fourth-instar nymphs developed into precocious adults in the fifth-instar. LmCPR knockdown decreased the response to precocene I in the nymphs, the occurrence rate of precocious adults induced by precocene I treatment reduced by 23.11%. Therefore, LmCPR may be involved in the activation of precocene I in L. migratoria. In addition, we generated an active recombinant LmCPR protein using a prokaryotic expression system, its activity in reducing cytochrome c was 33.13 ± 11.50 nmol CytCred/min/µg protein. This study lays the foundation for further research on the role of LmCPR in precocene I activation.


Asunto(s)
Locusta migratoria , NADPH-Ferrihemoproteína Reductasa , Animales , NADPH-Ferrihemoproteína Reductasa/genética , NADPH-Ferrihemoproteína Reductasa/metabolismo , Locusta migratoria/genética , Locusta migratoria/metabolismo , NADP/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
9.
Pestic Biochem Physiol ; 196: 105627, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37945261

RESUMEN

BACKGROUND: The cap 'n' collar (Cnc) belongs to the Basic Leucine Zipper (bZIP) transcription factor super family. Cap 'n' collar isoform C (CncC) is highly conserved in the animal kingdom. CncC contributes to the regulation of growth, development, and aging and takes part in the maintenance of homeostasis and the defense against endogenous and environmental stress. Insect CncC participates in the regulation of various kinds of stress-responsive genes and is involved in the development of insecticide resistance. RESULTS: In this study, one full-length CncC sequence of Locusta migratoria was identified and characterized. Upon RNAi silencing of LmCncC, insecticide bioassays showed that LmCncC played an essential role in deltamethrin and imidacloprid susceptibility. To fully investigate the downstream genes regulated by LmCncC and further identify the LmCncC-regulated genes involved in deltamethrin and imidacloprid susceptibility, a comparative transcriptome was constructed. Thirty-five up-regulated genes and 73 down-regulated genes were screened from dsLmCncC-knockdown individuals. We selected 22 LmCncC-regulated genes and verified their gene expression levels using RT-qPCR. Finally, six LmCYP450 genes belonging to the CYP6 family were selected as candidate detoxification genes, and LmCYP6FD1 and LmCYP6FE1 were further validated as detoxification genes of insecticides via RNAi, insecticide bioassays, and metabolite identification. CONCLUSIONS: Our data suggest that the locust CncC gene is associated with deltamethrin and imidacloprid susceptibility via the regulation of LmCYP6FD1 and LmCYP6FE1, respectively.


Asunto(s)
Insecticidas , Locusta migratoria , Humanos , Animales , Insecticidas/farmacología , Insecticidas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Locusta migratoria/genética , Locusta migratoria/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
10.
Pestic Biochem Physiol ; 196: 105620, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37945256

RESUMEN

Cytochrome P450 monooxygenases (P450s) are a superfamily of multifunctional heme-containing proteins and could function as odorant-degrading enzymes (ODEs) in insect olfactory systems. In our previous study, we identified a P450 gene from the antennal transcriptome of Locusta migratoria, LmCYP6MU1, which could be induced by a variety of volatiles. However, the regulatory mechanisms of this gene in response to volatiles remain unknown. In current study, we investigated the tissues and development stages expression patterns of LmCYP6MU1 and determined its olfactory function in the recognition of the main host plant volatiles which induced LmCYP6MU1 expression. The results showed that LmCYP6MU1 was antenna-rich and highly expressed throughout the antennal developmental stages of locusts. LmCYP6MU1 played important roles in the recognition of trans-2-hexen-1-al and nonanal. Insect CncC regulates the expression of P450 genes. We tested whether LmCncC regulates LmCYP6MU1 expression. It was found that LmCncC knockdown in the antennae resulted in the downregulation of LmCYP6MU1 and repressed the volatiles-mediated induction of LmCYP6MU1. LmCncC knockdown reduced the electroantennogram (EAG) and behavioral responses of locusts to volatiles. These results suggested that LmCncC could regulate the basal and volatiles-mediated inducible expression of LmCYP6MU1 responsible for the recognition of trans-2-hexen-1-al and nonanal. These findings provide an original basis for understanding the regulation mechanisms of LmCncC on LmCYP6MU1 expression and help us better understand the LmCncC-mediated olfactory plasticity.


Asunto(s)
Locusta migratoria , Animales , Locusta migratoria/genética , Locusta migratoria/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma , Regulación de la Expresión Génica , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Antenas de Artrópodos/metabolismo
11.
Heart Surg Forum ; 26(5): E463-E469, 2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37920092

RESUMEN

BACKGROUND: Drugs are the first choice of treatment for atrial fibrillation (AF), but there is currently a lack of efficient drug treatment options. The aim of this study was to investigate a combination drug treatment plan which may serve as a reference for the treatment of AF. METHODS: A total of 316 AF patients admitted to Jiaozhou Central Hospital in Qingdao from October 2020 to October 2022 were selected for this retrospective study. They were divided into a control group (CG, metoprolol, n = 156) and an observation group (OG, moracizine combined with metoprolol, n = 160) based on the treatment they received. The CG and OG groups were compared for clinical efficacy, occurrence of AF, cardiac output (CO), cardiac indexes (CI), stroke volume (SV), stroke indexes (SI) and improvement in QOL. RESULTS: The OG had a better effective rate of treatment, higher levels of CO, CI, SV and SI, and higher QOL scores compared to the CG, as well as a lower AF recurrence rate and AF burden (all p < 0.05). CONCLUSION: Moracizine combined with metoprolol is an effective treatment for AF patients. This drug combination was found to reduce the AF recurrence rate and burden in AF patients, and to improve their hemodynamic indices and QOL.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Humanos , Metoprolol/uso terapéutico , Fibrilación Atrial/epidemiología , Moricizina/uso terapéutico , Calidad de Vida , Antiarrítmicos/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Volumen Sistólico , Atrios Cardíacos
12.
Cancer Cell Int ; 22(1): 4, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986838

RESUMEN

BACKGROUND: Serine/threonine protein kinase 25 (STK25) plays an important role in regulating glucose and insulin homeostasis and in ectopic lipid accumulation. It directly affects the progression and prognosis of nonalcoholic fatty liver disease (NAFLD). However, the effects of STK25 on lipid metabolism in hepatocellular carcinoma (HCC) remain unexplored. The aim of this study was to investigate the role of STK25 in HCC and to elucidate the underlying mechanisms. METHODS: Immunohistochemistry was used to measure the expression of STK25 in hepatic tissues of HCC patients, and public datasets were used as supplementary material for predicting the expression of STK25 and the prognosis of patients with HCC. The interaction between STK25 and striatin (STRN) was determined by the STRING database, immunohistochemistry and western blot analyses. The involved signaling pathway was detected by the KEGG database and western blot. Moreover, the biological behaviors of the HCC cells were detected by wound healing assays, Transwell invasion assays and oil red O staining. Finally, it was verified again by xenograft model. RESULTS: STK25 is highly expressed in HCC patients and is associated with poor prognosis. STK25 knockdown inhibited the HCC cell invasion and proliferation, promotes apoptosis. Consistently, STK25 knockdown inhibited tumor growth in xenograft mouse model. Besides, STK25 deficiency decreased lipid synthesis, energy reserve, epithelial-mesenchymal transition (EMT) by down-regulating lipid metabolism signaling pathway. STRN could reverse the change of lipid metabolism. CONCLUSIONS: Our results demonstrated that STK25 interacted with STRN to regulates the energy reserve and EMT via lipid metabolism reprogramming. Accordingly, high expression of STK25 may be associated with HCC patients and poor prognosis, which implicates STK25 could be a potential target for lipid metabolism in cancer therapy.

13.
J Chem Phys ; 157(18): 180903, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36379784

RESUMEN

The spatial and energy resolutions of state-of-the-art transmission electron microscopes (TEMs) have surpassed 50 pm and 5 meV. However, with respect to the time domain, even the fastest detectors combined with the brightest sources may only be able to reach the microsecond timescale. Thus, conventional methods are incapable of resolving the myriad fundamental ultrafast (i.e., attosecond to picosecond) atomic-scale dynamics. The successful demonstration of femtosecond (fs) laser-based (LB) ultrafast electron microscopy (UEM) nearly 20 years ago provided a means to span this nearly 10-order-of-magnitude temporal gap. While nanometer-picosecond UEM studies of dynamics are now well established, ultrafast Å-scale imaging has gone largely unrealized. Further, while instrument development has rightly been an emphasis, and while new modalities and uses of pulsed-beam TEM continue to emerge, the overall chemical and materials application space has been only modestly explored to date. In this Perspective, we argue that these apparent shortfalls can be attributed to a simple lack of data and detail. We speculate that present work and continued growth of the field will ultimately lead to the realization that Å-scale fs dynamics can indeed be imaged with minimally modified UEM instrumentation and with repetition rates (frep) below-and perhaps even well below-1 MHz. We further argue that the use of low frep, whether for LB UEM or for chopped/bunched beams, significantly expands the accessible application space. This calls for systematically establishing modality-specific limits so that especially promising technologies can be pursued, thus, ultimately facilitating broader adoption as individual instrument capabilities expand.


Asunto(s)
Rayos Láser , Microscopía Electrónica de Transmisión , Microscopía Electrónica
14.
Langenbecks Arch Surg ; 407(1): 267-275, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34549336

RESUMEN

BACKGROUND: Anastomotic leakages (ALs) are one of the most serious complications following gastrointestinal anastomosis. Currently, very few operative measures are available for the prevention of ALs. This pilot study aimed to evaluate the safety and efficacy of tube enterostomy (T-E) for the prevention of ALs in patients with high-risk intestinal anastomosis. METHODS: In this retrospective study, demographic data and postoperative outcomes were compared among patients who received T-E and two historical cohorts: one group that underwent primary anastomosis without T-E (non-T-E group) and another that underwent conventional stoma construction without anastomosis (stoma group). The operative procedures were selected according to a scoring system that quantitatively evaluated risk of Als (Zhongnan score). RESULTS: From March 2017 to March 2020, a total of 45 consecutive patients were enrolled in the T-E group. Among these patients, 53.3% (24/45) were diagnosed with Crohn's disease (CD), and 66.7% (30/45) of them underwent emergency surgery. After propensity score matching, the demographic data were comparable among the three groups. One case of AL (2.2%) occurred in the T-E group, while four cases of ALs (8.9%, 4/45) were found in the non-T-E group (p = 0.13). Tube feeding was provided to 33.3% (15/45) of the T-E patients. Major tube-related complications included one tube dislocation (2.2%) and 3 (6.7%) minor leakages after tube withdrawal (treated conservatively). One death occurred in the stoma group. In the subgroup analysis of CD patients, lower rates of ALs and abdominal abscesses were observed in the T-E group than in the non-T-E and stoma subgroups, but the differences were not significant. CONCLUSIONS: T-E seems to be a safe and feasible operative method for the protection of high-risk intestinal anastomosis, can be reversed and can provide enteral feeding with acceptable tube-related complications. Further studies are needed to validate the role of T-E.


Asunto(s)
Fuga Anastomótica , Enterostomía , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/epidemiología , Fuga Anastomótica/etiología , Fuga Anastomótica/prevención & control , Humanos , Proyectos Piloto , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos
15.
Pestic Biochem Physiol ; 188: 105255, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464360

RESUMEN

Cytochrome P450 monooxygenases (P450s) are a large superfamily of heme-thiolate proteins and play a vital role in the biosynthesis and inactivation of endogenous substances as well as the detoxification of exogenous substances. They also function as odor-degrading enzymes (ODEs) in insect olfactory sensory systems. In the present study, a P450 gene was obtained from the antennae of Locusta migratoria and named as CYP6FD5. Multiple alignment of P450 proteins revealed that LmCYP6FD5 contained five conserved motifs, including the helix C motif, an oxygen-binding site, helix K motif, a meander region, and the haem-binding motif. The expression of LmCYP6FD5 in various tissues and antennal development stages was determined by using RT-qPCR. Our results showed that LmCYP6FD5 was antenna-specific and highly expressed throughout the antennal developmental stages of female and male locusts. Furthermore, the role of LmCYP6FD5 in the perception of host plant volatiles was assessed using RNAi in combination with electroantennogram (EAG) and behavioral responses. Our findings showed that after silencing LmCYP6FD5, the EAG responses of female and male locusts to the main volatiles of gramineous plants, including trans-2-Hexen-1-al, cis-3-Hexenyl acetate, and decanal, were significantly diminished. Moreover, a significant decrease in EAG response of male antennae to benzaldehyde was also observed. In addition, behavioral assay showed that the locust response to single volatile from host plant or wheat remained unchanged after the silencing of LmCYP6FD5. Antenna-specific expression and EAG responses of locusts to host plant volatiles still suggested that LmCYP6FD5 was potentially involved in host plant recognition, although no behavioral changes were observed.


Asunto(s)
Locusta migratoria , Animales , Locusta migratoria/genética , Sitios de Unión , Bioensayo
16.
Sensors (Basel) ; 22(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35684862

RESUMEN

The human body is an incredible and complex sensing system. Environmental factors trigger a wide range of automatic neurophysiological responses. Biometric sensors can capture these responses in real time, providing clues about the underlying biophysical mechanisms. In this prototype study, we demonstrate an experimental paradigm to holistically capture and evaluate the interactions between an environmental context and physiological markers of an individual operating that environment. A cyclist equipped with a biometric sensing suite is followed by an environmental survey vehicle during outdoor bike rides. The interactions between environment and physiology are then evaluated though the development of empirical machine learning models, which estimate particulate matter concentrations from biometric variables alone. Here, we show biometric variables can be used to accurately estimate particulate matter concentrations at ultra-fine spatial scales with high fidelity (r2 = 0.91) and that smaller particles are better estimated than larger ones. Inferring environmental conditions solely from biometric measurements allows us to disentangle key interactions between the environment and the body. This work sets the stage for future investigations of these interactions for a larger number of factors, e.g., black carbon, CO2, NO/NO2/NOx, and ozone. By tapping into our body's 'built-in' sensing abilities, we can gain insights into how our environment influences our physical health and cognitive performance.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Cognición , Monitoreo del Ambiente , Humanos , Material Particulado/análisis
17.
Nano Lett ; 21(17): 7332-7338, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34406014

RESUMEN

Step edges are an important and prevalent topological feature that influence catalytic, electronic, vibrational, and structural properties arising from modulation of atomic-scale force fields due to edge-atom relaxation. Direct probing of ultrafast atomic-to-nanoscale lattice dynamics at individual steps poses a particularly significant challenge owing to demanding spatiotemporal resolution requirements. Here, we achieve such resolutions with femtosecond 4D ultrafast electron microscopy and directly image nanometer-variant softening of photoexcited phonons at individual surface steps. We find large degrees of softening precisely at the step position, with a thickness-dependent, strain-induced frequency modulation extending tens of nanometers laterally from the atomic-scale discontinuity. The effect originates from anisotropic bond dilation and photoinduced incoherent atomic displacements delineated by abrupt molecular-layer cessation. The magnitude and spatiotemporal extent of softening is quantitatively described with a finite-element transient-deformation model. The high spatiotemporal resolutions demonstrated here enable uncovering of new insights into atomic-scale structure-function relationships of highly defect-sensitive, functional materials.


Asunto(s)
Fonones , Microscopía Electrónica
18.
J Obstet Gynaecol ; 42(6): 2272-2281, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35421318

RESUMEN

This meta-analysis aimed to determine the accuracy of transvaginal ultrasound (TVS) and pelvic magnetic resonance imaging (MRI) in diagnosing urinary tract endometriosis (UTE). A comprehensive search of the Pubmed and Embase was conducted between January 1989 and June 2020. Studies that described the accuracy of MRI or TVS for the diagnosis of UTE using surgical data as the reference standard were included. Of the 913 citations identified, 23 studies were analysed. For detection of endometriosis in bladder endometriosis (BE), the overall pooled sensitivities of TVS and MRI were 72% and 68% respectively, and their specificities were 99% and 100% respectively. For detection of endometriosis in the ureteral endometriosis (UE), the overall pooled sensitivities of TVS and MRI were 97% and 87% respectively, and their specificities were both 100%. In conclusion, both TVS and MRI provide good accuracy with specific strong points in diagnosing UTE and seem useful first-line methods from a clinical perspective. Besides, pelvic MRI and TVS are more accurate for predicting UTE localised in the ureter than bladder, especially in terms of sensitivity.IMPACT STATEMENTWhat is already known on this subject? Previous studies have confirmed high diagnostic value of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) on bladder endometriosis (BE) respectively. However, high heterogeneity was found for both sensitivity and specificity and no meta-analysis has yet been performed to test the diagnostic value of TVS and MRI for ureteral endometriosis (UE).What the results of this study add? In this meta-analysis, we firstly confirmed high diagnostic value of TVS and MRI on UE respectively. For detection of UE, the overall pooled sensitivities of TVS and MRI were 97% and 87% respectively, and their specificities were both 100%.What the implications are of these findings for clinical practice and/or further research? Early preoperative diagnosis and accurate understanding of the widespread distribution of endometriosis are prerequisites for radical surgical in UTE. In the present study, we updated the previous results on the accuracy of TVS and MRI for the diagnosis of BE and firstly confirmed high diagnostic value of TVS and MRI on UE. Both TVS and MRI provide good accuracy with specific strong points in diagnosing UTE and seem useful first-line methods from a clinical perspective.


Asunto(s)
Endometriosis , Enfermedades de la Vejiga Urinaria , Enfermedades Urológicas , Endometriosis/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Sensibilidad y Especificidad , Ultrasonografía/métodos , Enfermedades de la Vejiga Urinaria/diagnóstico por imagen , Enfermedades Urológicas/diagnóstico por imagen , Vagina/diagnóstico por imagen
19.
Sensors (Basel) ; 21(18)2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34577466

RESUMEN

Sunlight incident on the Earth's atmosphere is essential for life, and it is the driving force of a host of photo-chemical and environmental processes, such as the radiative heating of the atmosphere. We report the description and application of a physical methodology relative to how an ensemble of very low-cost sensors (with a total cost of <$20, less than 0.5% of the cost of the reference sensor) can be used to provide wavelength resolved irradiance spectra with a resolution of 1 nm between 360-780 nm by calibrating against a reference sensor using machine learning. These low-cost sensor ensembles are calibrated using machine learning and can effectively reproduce the observations made by an NIST calibrated reference instrument (Konica Minolta CL-500A with a cost of around USD 6000). The correlation coefficient between the reference sensor and the calibrated low-cost sensor ensemble has been optimized to have R2> 0.99. Both the circuits used and the code have been made publicly available. By accurately calibrating the low-cost sensors, we are able to distribute a large number of low-cost sensors in a neighborhood scale area. It provides unprecedented spatial and temporal insights into the micro-scale variability of the wavelength resolved irradiance, which is relevant for air quality, environmental and agronomy applications.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Calibración , Monitoreo del Ambiente , Aprendizaje Automático , Material Particulado/análisis
20.
Molecules ; 26(12)2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34205583

RESUMEN

In this study, we explore a new method based on color variation data to derive the kinetics of the entire process of the hydration of alkali-activated slag (AAS). Using this image analysis technique, we can monitor the induction period that cannot be observed using conventional microcalorimetry techniques. Color variation was recorded across a sequence of 9999 images, which were processed via MATLAB software package. Further, an average pixel value (APV) was determined to represent the color in each image. Reaction parameters, such as color variation velocity v(t), reaction speed ε(t), and hydration degree α(t), that govern the entire hydration process were determined. On the basis of the reaction parameters and a Krstulovic-Dabic kinetic model, integral and differential equations were derived to simulate the three basic processes of AAS hydration. Equations describing the reaction kinetics of AAS with solutions of three different concentrations of NaOH were extracted using this method.

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