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1.
Nature ; 617(7961): 488-492, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37100906

RESUMEN

The newly discovered kagome superconductors represent a promising platform for investigating the interplay between band topology, electronic order and lattice geometry1-9. Despite extensive research efforts on this system, the nature of the superconducting ground state remains elusive10-17. In particular, consensus on the electron pairing symmetry has not been achieved so far18-20, in part owing to the lack of a momentum-resolved measurement of the superconducting gap structure. Here we report the direct observation of a nodeless, nearly isotropic and orbital-independent superconducting gap in the momentum space of two exemplary CsV3Sb5-derived kagome superconductors-Cs(V0.93Nb0.07)3Sb5 and Cs(V0.86Ta0.14)3Sb5-using ultrahigh-resolution and low-temperature angle-resolved photoemission spectroscopy. Remarkably, such a gap structure is robust to the appearance or absence of charge order in the normal state, tuned by isovalent Nb/Ta substitutions of V. Our comprehensive characterizations of the superconducting gap provide indispensable information on the electron pairing symmetry of kagome superconductors, and advance our understanding of the superconductivity and intertwined electronic orders in quantum materials.

2.
Nat Mater ; 21(10): 1111-1115, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35835819

RESUMEN

Room-temperature realization of macroscopic quantum phases is one of the major pursuits in fundamental physics1,2. The quantum spin Hall phase3-6 is a topological quantum phase that features a two-dimensional insulating bulk and a helical edge state. Here we use vector magnetic field and variable temperature based scanning tunnelling microscopy to provide micro-spectroscopic evidence for a room-temperature quantum spin Hall edge state on the surface of the higher-order topological insulator Bi4Br4. We find that the atomically resolved lattice exhibits a large insulating gap of over 200 meV, and an atomically sharp monolayer step edge hosts an in-gap gapless state, suggesting topological bulk-boundary correspondence. An external magnetic field can gap the edge state, consistent with the time-reversal symmetry protection inherent in the underlying band topology. We further identify the geometrical hybridization of such edge states, which not only supports the Z2 topology of the quantum spin Hall state but also visualizes the building blocks of the higher-order topological insulator phase. Our results further encourage the exploration of high-temperature transport quantization of the putative topological phase reported here.

3.
Phys Rev Lett ; 131(2): 026701, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505968

RESUMEN

In kagome metal CsV_{3}Sb_{5}, multiple intertwined orders are accompanied by both electronic and structural instabilities. These exotic orders have attracted much recent attention, but their origins remain elusive. The newly discovered CsTi_{3}Bi_{5} is a Ti-based kagome metal to parallel CsV_{3}Sb_{5}. Here, we report angle-resolved photoemission experiments and first-principles calculations on pristine and Cs-doped CsTi_{3}Bi_{5} samples. Our results reveal that the van Hove singularity (vHS) in CsTi_{3}Bi_{5} can be tuned in a large energy range without structural instability, different from that in CsV_{3}Sb_{5}. As such, CsTi_{3}Bi_{5} provides a complementary platform to disentangle and investigate the electronic instability with a tunable vHS in kagome metals.

4.
Sensors (Basel) ; 23(7)2023 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37050534

RESUMEN

Drowsiness poses a serious challenge to road safety and various in-cabin sensing technologies have been experimented with to monitor driver alertness. Cameras offer a convenient means for contactless sensing, but they may violate user privacy and require complex algorithms to accommodate user (e.g., sunglasses) and environmental (e.g., lighting conditions) constraints. This paper presents a lightweight convolution neural network that measures eye closure based on eye images captured by a wearable glass prototype, which features a hot mirror-based design that allows the camera to be installed on the glass temples. The experimental results showed that the wearable glass prototype, with the neural network in its core, was highly effective in detecting eye blinks. The blink rate derived from the glass output was highly consistent with an industrial gold standard EyeLink eye-tracker. As eye blink characteristics are sensitive measures of driver drowsiness, the glass prototype and the lightweight neural network presented in this paper would provide a computationally efficient yet viable solution for real-world applications.


Asunto(s)
Conducción de Automóvil , Dispositivos Electrónicos Vestibles , Fases del Sueño , Vigilia , Parpadeo
5.
Phys Rev Lett ; 129(20): 206402, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36461993

RESUMEN

Kagome metals AV_{3}Sb_{5} (A=K, Rb, and Cs) exhibit a characteristic superconducting ground state coexisting with a charge density wave (CDW), whereas the mechanisms of the superconductivity and CDW have yet to be clarified. Here we report a systematic angle-resolved photoemission spectroscopy (ARPES) study of Cs(V_{1-x}Nb_{x})_{3}Sb_{5} as a function of Nb content x, where isovalent Nb substitution causes an enhancement of superconducting transition temperature (T_{c}) and the reduction of CDW temperature (T_{CDW}). We found that the Nb substitution shifts the Sb-derived electron band at the Γ point downward and simultaneously moves the V-derived band around the M point upward to lift up the saddle point (SP) away from the Fermi level, leading to the reduction of the CDW-gap magnitude and T_{CDW}. This indicates a primary role of the SP density of states to stabilize the CDW. The present result also suggests that the enhancement of superconductivity by Nb substitution is caused by the cooperation between the expansion of the Sb-derived electron pocket and the recovery of the V-derived density of states at the Fermi level.

6.
Arch Microbiol ; 204(8): 477, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35829968

RESUMEN

Inositol phosphorylceramide (IPC) participates in hyphal growth and serves as a signaling molecule that enables fungi to adapt to diverse environments. Here, a gene, encodes IPC synthase, was identified from the Aspergillus oryzae 3.042 genome and designated AoAur1. The characteristics, phylogenetic evolution, and resistance to aureobasidin A of AoAur1 were analyzed. The expression pattern of AoAur1 was markedly downregulated under temperature stress. Additionally, an RNAi-AoAur1 strain in which the AoAur1 expression was inhibited had mycelial that grew more quickly, had a higher frequency of hyphal fusion, and was more resistant to high-temperature stress than the control. Gene expression profiles showed that the genes related to IPC biosynthesis were obviously downregulated, while AoCerS, which participates in dihydroceramide biosynthesis, increased in the RNAi-AoAur1 strain at the three temperature treatments. A metabolomic analysis revealed that the intracellular IPC content decreased, and the accumulation of dihydroceramide and galactosylceramide increased significantly in the RNAi-AoAur1 strain. Thus, the inhibition of AoAur1 reduced IPC level followed by an increase in the contents of dihydroceramide and galactosylceramide that promote mycelial growth and the formation of spores in the RNAi-AoAur1 strain. Interestingly, the inhibition of AoAur1 also induced the expression of hyphal fusion-related genes, which promote hyphal fusion, thus, contributing to the transduction of stress signal to enhance the ability of cells to adapt to temperature stress. Our results demonstrated that the downregulation of AoAur1 and a decrease in the accumulation of IPC is one of the mechanisms that enables A. oryzae to adapt low- and high-temperature stress.


Asunto(s)
Aspergillus oryzae , Adaptación Fisiológica , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Galactosilceramidas/metabolismo , Filogenia , Temperatura
7.
J Ind Microbiol Biotechnol ; 46(12): 1769-1780, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31541399

RESUMEN

The ZRT, IRT-like protein (ZIP) family exists in many species and plays an important role in many biological processes, but little is known about ZIP genes in Aspergillus oryzae. Here, 10 ZIP genes in A. oryzae were identified and these were classified into four groups based on phylogenetic analysis. The structures of these AoZip genes were determined, which indicated a great divergence of AoZip members from different groups. Synteny analysis revealed that AoZip7, AoZip8, and AoZip10 are conserved among Aspergillus species. We also found that the promoter regions of AoZip2, AoZip7, AoZip8, and AoZip10 contain multiple conserved response elements. Expression analysis revealed that AoZips exhibited different expression patterns in response to different metal treatments. Moreover, overexpression and RNA-interference (RNAi) of AoZip2 led to a decrease in mycelium growth diameter and inhibited conidia formation. AoZip2 overexpression and RNAi strains showed distinct sensitivity to severely Zn/Mn-depleted stress. In addition, kojic acid production was markedly lower in AoZip2 overexpression and RNAi strains than in the control strains, and the expression of kojA, kojR, and kojT was down-regulated in AoZip2 overexpression and RNAi strains. This study provides new insights into our understanding of ZIP genes and lays a foundation for further investigation of their roles in Aspergillus oryzae.


Asunto(s)
Aspergillus oryzae/metabolismo , Proteínas de Transporte de Catión/metabolismo , Proteínas Fúngicas/metabolismo , Pironas/metabolismo , Aspergillus oryzae/genética , Proteínas de Transporte de Catión/genética , Proteínas Fúngicas/genética , Filogenia
8.
Adv Sci (Weinh) ; : e2309003, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38828764

RESUMEN

Applying lattice strain to thin films, a critical factor to tailor their properties such as stabilizing a structural phase unstable at ambient pressure, generally necessitates heteroepitaxial growth to control the lattice mismatch with substrate. Therefore, while homoepitaxy, the growth of thin film on a substrate made of the same material, is a useful method to fabricate high-quality thin films, its application to studying strain-induced structural phases is limited. Contrary to this general belief, here the quasi-homoepitaxial growth of Cs and Rb thin films is reported with substantial in-plane compressive strain. This is achieved by utilizing the alkali-metal layer existing in bulk crystal of kagome metals AV3Sb5 (A = Cs and Rb) as a structural template. The angle-resolved photoemission spectroscopy measurements reveal the formation of metallic quantum well states and notable thickness-dependent quasiparticle lifetime. Comparison with density functional theory calculations suggests that the obtained thin films crystalize in the face-centered cubic structure, which is typically stable only under high pressure in bulk crystals. These findings provide a useful approach for synthesizing highly strained thin films by quasi-homoepitaxy, and pave the way for investigating many-body interactions in Fermi liquids with tunable dimensionality.

9.
Nat Commun ; 15(1): 2888, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605015

RESUMEN

Superconductivity is caused by electron pairs that are canonically isotropic, whereas some exotic superconductors are known to exhibit non-trivial anisotropy stemming from unconventional pairings. However, superconductors with hexagonal symmetry, the highest rotational symmetry allowed in crystals, exceptionally have strong constraint that is called emergent rotational symmetry (ERS): anisotropic properties should be very weak especially near the critical temperature Tc even for unconventional pairings such as d-wave states. Here, we investigate superconducting anisotropy of the recently-found hexagonal Kagome superconductor CsV3Sb5, which is known to exhibit various intriguing phenomena originating from its undistorted Kagome lattice formed by vanadium atoms. Based on calorimetry performed under accurate two-axis field-direction control, we discover a combination of six- and two-fold anisotropies in the in-plane upper critical field. Both anisotropies, robust up to very close to Tc, are beyond predictions of standard theories. We infer that this clear ERS violation with nematicity is best explained by multi-component nematic superconducting order parameter in CsV3Sb5 intertwined with symmetry breakings caused by the underlying charge-density-wave order.

10.
Nat Commun ; 15(1): 5038, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866771

RESUMEN

Transition metal compounds with kagome structure have been found to exhibit a variety of exotic structural, electronic, and magnetic orders. These orders are competing with energies very close to each other, resulting in complex phase transitions. Some of the phases are easily observable, such as the charge density wave (CDW) and the superconducting phase, while others are more challenging to identify and characterize. Here we present magneto-transport evidence of a new phase below ~ 35 K in the kagome topological metal CsV3Sb5 (CVS) thin flakes between the CDW and the superconducting transition temperatures. This phase is characterized by six-fold rotational symmetry in the in-plane magnetoresistance (MR) and is connected to the orbital current order in CVS. Furthermore, the phase is characterized by a large in-plane negative magnetoresistance, which suggests the existence of a three-dimensional, magnetic field-tunable orbital current ordered phase. Our results highlight the potential of magneto-transport to reveal the interactions between exotic quantum states of matter and to uncover the symmetry of such hidden phases.

11.
Sci Rep ; 14(1): 9580, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671053

RESUMEN

Kagome superconductors AV3Sb5 (A = K, Rb, and Cs) have attracted enormous interest due to the coexistence of charge density wave (CDW) order, unconventional superconductivity (SC) and anomalous Hall effect (AHE). In this paper, we reported an intensive investigation on Cs(V1-xTax)3Sb5 single crystals with systematic Ta doping. Ta was confirmed to be doped into V-site in the Kagome layer from both single crystal X-ray diffraction structural refinement and scanning transmission electron microscopy observation. The highest Ta doping level was found to be about 16%, which is more than twice as much as 7% in Nb-doped CsV3Sb5. With the increase of Ta doping, CDW order was gradually suppressed and finally vanished when the doping level reached to more than 8%. Meanwhile, superconductivity was enhanced with a maximum critical temperature (Tc) of 5.3 K, which is the highest Tc in the bulk crystal of this Kagome system at ambient pressure so far. The µ0Hc2(T) behavior demonstrates that the system is still a two-band superconductor after Ta doping. Based on the electrical transport measurement, a phase diagram was set up to exhibit the evolution of CDW and SC in the Cs(V1-xTax)3Sb5 system. These findings pave a new way to search for new superconductors with higher Tc in the AV3Sb5 family and establish a new platform for tuning and controlling the multiple orders and superconducting states.

12.
China CDC Wkly ; 6(3): 56-59, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38269358

RESUMEN

What is already known about this topic?: Fatal poisonings caused by wild mushrooms containing amanita toxins pose a significant threat in the southern regions of China. These toxins primarily induce gastrointestinal symptoms initially, which are then followed by potentially life-threatening acute liver damage. What is added by this report?: This report contributes to the existing knowledge on these cases of poisoning by documenting the second occurrences in Hebei Province and the first occurrences in Xingtai City. Five individuals reported consuming wild mushrooms from the same origin, and laboratory tests confirmed the presence of α-amanitin in their blood samples. What are the implications for public health practice?: This underscores the risk associated with the collection and consumption of amanita toxin-containing mushrooms in Hebei. It is important to note that the identification of toxic and non-toxic mushrooms should not solely rely on personal experience or appearance.

13.
Biophys J ; 104(10): 2282-94, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23708368

RESUMEN

The specification and maintenance of cell fates is essential to the development of multicellular organisms. However, the precise molecular mechanisms in cell fate selection are, to our knowledge, poorly understood due to the complexity of multiple interconnected pathways. In this study, model-based quantitative analysis is used to explore how to maintain distinguished cell fates between cell-cycle commitment and mating arrest in budding yeast. We develop a full mathematical model of an interlinked regulatory network based on the available experimental data. By theoretically defining the Start transition point, the model is able to reproduce many experimental observations of the dynamical behaviors in wild-type cells as well as in Ste5-8A and Far1-S87A mutants. Furthermore, we demonstrate that a moderate ratio between Cln1/2→Far1 inhibition and Cln1/2→Ste5 inhibition is required to ensure a successful switch between different cell fates. We also show that the different ratios of the mutual Cln1/2 and Far1 inhibition determine the different cell fates. In addition, based on a new, definition of network entropy, we find that the Start point in wild-type cells coincides with the system's point of maximum entropy. This result indicates that Start is a transition point in the network entropy. Therefore, we theoretically explain the Start point from a network dynamics standpoint. Moreover, we analyze the biological bistablity of our model through bifurcation analysis. We find that the Cln1/2 and Cln3 production rates and the nonlinearity of SBF regulation on Cln1/2 production are potential determinants for irreversible entry into a new cell fate. Finally, the quantitative computations further reveal that high specificity and fidelity of the cell-cycle and mating pathways can guarantee specific cell-fate selection. These findings show that quantitative analysis and simulations with a mathematical model are useful tools for understanding the molecular mechanisms in cell-fate decisions.


Asunto(s)
Ciclo Celular , Modelos Biológicos , Saccharomyces cerevisiae/citología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Ciclinas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
14.
Heliyon ; 9(4): e14941, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37025776

RESUMEN

Background: To construct and validate a simple and easily administered scoring tool for the prediction of short-term prognostic survival in adult patients with sepsis. Methods: This study is a retrospective and prospective cohort study. A total of 382 patients with sepsis. 274 sepsis patients from January 2020 to December 2020 were collected as the modeling group and 54 sepsis patients from January 2021 to December 2021 and April to May 2022 in the hospital were randomly collected as the validation group. They were divided into survival and non-survival groups according to the outcome. The receiver operating characteristic (ROC) curves were plotted with subgroup analysis. The resulting models were tested using the Hosmer-Lemeshow test. The prognostic value of the variables on prognosis was expressed using the area under the receiver operating characteristic curve (AUC). A scoring tool was constructed and tested for the prognostic value of this score in the validation group. Results: The model had an AUC of 0.880 [95% CI (0.838-0.922), P < 0.001], model sensitivity of 81.15%, and specificity of 80.26% for predicting short-term prognosis in patients with sepsis. Further simplifying the model scoring rules and adding the lactate variable, the AUCs was 0.876 [95% CI (0.833-0.918)], P < 0.001], sensitivity was 78.69%, specificity was 82.89%, and scoring criteria were established. the AUCs of the internally validated model in 2021 and 2022 were 0.968 [95% CI (0.916 to 1.000), P < 0.001] and 0.943 [95% CI (0.873 to 1.000), P < 0.001], indicating that the constructed scoring tool has a good predictive value for short-term survival outcomes in patients with sepsis. Conclusions: Age, shock, lactate, lactate/albumin ratio (L/A), and interleukin-6 (IL-6) are five risk factors for adult sepsis prognosis in an early emergency. This scoring tool is developed to quickly assess the short-term survival outcome in adult sepsis patients. It is straightforward and easy to administer. It also has a high prognostic predictive value.The Chinese Clinical Trial Registry (ChiCTR2200058375).

15.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(1): 61-65, 2023 Jan.
Artículo en Zh | MEDLINE | ID: mdl-36880240

RESUMEN

OBJECTIVE: To investigate the prognostic value of early serum lactate, albumin, and lactate/albumin ratio (L/A) on the 28-day prognosis of adult patients with sepsis. METHODS: A retrospective cohort study was conducted among adult patients with sepsis admitted to the First Affiliated Hospital of Xinjiang Medical University from January to December in 2020. Gender, age, comorbidities, lactate within 24 hours of admission, albumin, L/A, interleukin-6 (IL-6), procalcitonin (PCT), C-reactive protein (CRP) and 28-day prognosis were recorded. The receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of lactate, albumin and L/A for 28-day mortality in patients with sepsis. Subgroup analysis of patients was performed according to the best cut-off value, Kaplan-Meier survival curves were drawn, and the 28-day cumulative survival of patients with sepsis was analyzed. RESULTS: A total of 274 patients with sepsis were included, and 122 patients died at 28 days, with a 28-day mortality of 44.53%. Compared with the survival group, the age, the proportion of pulmonary infection, the proportion of shock, lactate, L/A and IL-6 in the death group were significantly increased, and albumin was significantly decreased [age (years): 65 (51, 79) vs. 57 (48, 73), pulmonary infection: 75.4% vs. 53.3%, shock: 37.7% vs. 15.1%, lactate (mmol/L): 4.76 (2.95, 9.23) vs. 2.21 (1.44, 3.19), L/A: 0.18 (0.10, 0.35) vs. 0.08 (0.05, 0.11), IL-6 (ng/L): 337.00 (97.73, 2 318.50) vs. 55.88 (25.26, 150.65), albumin (g/L): 27.68 (21.02, 33.03) vs. 29.62 (25.25, 34.23), all P < 0.05]. The area under the ROC curve (AUC) and 95% confidence interval (95%CI) of lactate, albumin, and L/A were 0.794 (95%CI was 0.741-0.840), 0.589 (95%CI was 0.528-0.647), 0.807 (95%CI was 0.755-0.852) for predicting 28-day mortality in sepsis patients. The optimal diagnostic cut-off value of lactate was 4.07 mmol/L, the sensitivity was 57.38%, the specificity was 92.76%. The optimal diagnostic cut-off value of albumin was 22.28 g/L, the sensitivity was 31.15%, the specificity was 92.76%. The optimal diagnostic cut-off of L/A was 0.16, the sensitivity was 54.92%, and the specificity was 95.39%. Subgroup analysis showed that the 28-day mortality of sepsis patients in the L/A > 0.16 group was significantly higher than that in the L/A ≤ 0.16 group [90.5% (67/74) vs. 27.5% (55/200), P < 0.001]. The 28-day mortality of sepsis patients in the albumin ≤ 22.28 g/L group was significantly higher than that in the albumin > 22.28 g/L group [77.6% (38/49) vs. 37.3% (84/225), P < 0.001]. The 28-day mortality in the group with lactate > 4.07 mmol/L was significantly higher than that in the group with lactate ≤ 4.07 mmol/L [86.4% (70/81) vs. 26.9% (52/193), P < 0.001]. The three were consistent with the analysis results of Kaplan-Meier survival curve. CONCLUSIONS: The early serum lactate, albumin, and L/A were all valuable in predicting the 28-day prognosis of patients with sepsis, and L/A was better than lactate and albumin.


Asunto(s)
Ácido Láctico , Sepsis , Adulto , Humanos , Interleucina-6 , Estudios Retrospectivos , Albúminas , Pronóstico , Sepsis/diagnóstico
16.
J Phys Condens Matter ; 35(23)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36913735

RESUMEN

Bi4Br4is a quasi-one-dimensional van der Waals topological insulator with novel electronic properties. Several efforts have been devoted to the understanding of its bulk form, yet it remains a challenge to explore the transport properties in low-dimensional structures due to the difficulty of device fabrication. Here we report for the first time a gate-tunable transport in exfoliated Bi4Br4nanobelts. Notable two-frequency Shubnikov-de Haas oscillations oscillations are discovered at low temperatures, with the low- and high-frequency parts coming from the three-dimensional bulk state and the two-dimensional surface state, respectively. In addition, ambipolar field effect is realized with a longitudinal resistance peak and a sign reverse in the Hall coefficient. Our successful measurements of quantum oscillations and realization of gate-tunable transport lay a foundation for further investigation of novel topological properties and room-temperature quantum spin Hall states in Bi4Br4.

17.
Sci Bull (Beijing) ; 68(4): 417-423, 2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36740530

RESUMEN

The bulk-boundary correspondence is a critical concept in topological quantum materials. For instance, a quantum spin Hall insulator features a bulk insulating gap with gapless helical boundary states protected by the underlying Z2 topology. However, the bulk-boundary dichotomy and distinction are rarely explored in optical experiments, which can provide unique information about topological charge carriers beyond transport and electronic spectroscopy techniques. Here, we utilize mid-infrared absorption micro-spectroscopy and pump-probe micro-spectroscopy to elucidate the bulk-boundary optical responses of Bi4Br4, a recently discovered room-temperature quantum spin Hall insulator. Benefiting from the low energy of infrared photons and the high spatial resolution, we unambiguously resolve a strong absorption from the boundary states while the bulk absorption is suppressed by its insulating gap. Moreover, the boundary absorption exhibits strong polarization anisotropy, consistent with the one-dimensional nature of the topological boundary states. Our infrared pump-probe microscopy further measures a substantially increased carrier lifetime for the boundary states, which reaches one nanosecond scale. The nanosecond lifetime is about one to two orders longer than that of most topological materials and can be attributed to the linear dispersion nature of the helical boundary states. Our findings demonstrate the optical bulk-boundary dichotomy in a topological material and provide a proof-of-principal methodology for studying topological optoelectronics.

18.
Biomed Res Int ; 2022: 9858820, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35872871

RESUMEN

Background: Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) has received increasing attention and application as an effective noninvasive mode of ventilation in the treatment of clinical anesthesia and critically ill patients. The conclusions reached in clinical studies of THRIVE and facemask oxygenation are still controversial, and the main objective of this systematic review is to determine the advantages of THRIVE over facemask oxygenation in intensive care units, respiratory medicine, and perioperative preoxygenation. Methods: PubMed, Embase, Web of Science, and Cochrane Library have search restrictions. The search library was full of English language articles from the first publication to 15 July 2021. Eligible randomized controlled study designs were included. 245 records were screened, and 5 studies met the inclusion criteria, enrolling a total of 235 patients. Results: Studying the THRIVE group compared to the facemask group, three studies analyzing intubation time showed that there is no difference in the effect of THRIVE and facemasks (MD -1.22, 95% CI -7.23 to 4.78, and P = 0.69 > 0.05). Three studies analyzing apnea showed that there was no difference between the two groups (SMD 1, 95% CI -0.76 to 2.76, and P = 0.27 > 0.05). Three studies analyzing PaO2 after preoxygenation showed that THRIVE is more effective than facemasks (MD 72.58, 95% CI 31.25 to 113.90, Z = 3.44, and P < 0.001). Two studies analyzing oxygen saturation SpO2 after successful intubation showed that there was no difference in the effectiveness (MD 0.09, 95% CI -1.03 to 1.22, and P = 0.87 > 0.05). Two studies analyzing PCO2 after complete paralysis or intubation preoxygenation showed that there was no difference between the two groups (MD 2.76, 95% CI -1.74 to 7.26, and P = 0.23 > 0.05). Conclusions: THRIVE does not have a greater advantage over a facemask in improving apnea time, oxygenation time, PCO2, and SpO2, but it has an advantage in improving arterial partial pressure of oxygen (PaO2) after preoxygenation, which can improve PaO2 well. This trial is registered with the protocol registration number CRD42021268143.


Asunto(s)
Insuflación , Apnea , Humanos , Insuflación/métodos , Máscaras , Oxígeno , Terapia por Inhalación de Oxígeno , Presión Parcial
19.
Medicine (Baltimore) ; 101(36): e30491, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36086783

RESUMEN

RATIONALE: Intentional or unintentional exposure to asphyxiating gases is a significant public health concern worldwide. Argon poisoning is fatal, and its onset is primarily due to neurological damage. PATIENT CONCERNS: A 22-year-old man was admitted to the hospital for argon gas poisoning. While working in a plant containing argon gas, he suddenly lost consciousness, recovered consciousness slightly after on-site treatment, answered questions, and had impaired memory, sensory dullness, normal cognition, and symptoms of dizziness and headache. DIAGNOSIS: Asphyxiating gas poisoning (argon gas poisoning), metabolic encephalopathy, and hepatic insufficiency. INTERVENTIONS: Immediately after admission, the patient was treated with nasal cannula oxygen 3 L/min and hyperbaric oxygen therapy once a day. Mecobalamin tablets 500 µg were given orally 3 times a day. Oral Ginkgo biloba extract tablets 40 mg 3 times a day. OUTCOME: The patient was discharged after treatment with hyperbaric oxygen therapy and nerve-nourishing drugs, with no discomfort, clear consciousness, and good memory, and was followed up by telephone for 2 consecutive months, and the patient is now in good condition with no discomfort. LESSON: This case describes the pathogenesis, neurological damage, and rescue process of argon gas poisoning. Argon poisoning was found to damage bilateral cerebellar hemispheres and bilateral hippocampal regions, affecting the patient's consciousness and memory, and was found to cause abnormal liver function and heart rate disorders.


Asunto(s)
Intoxicación por Monóxido de Carbono , Intoxicación por Gas , Oxigenoterapia Hiperbárica , Adulto , Argón , Intoxicación por Monóxido de Carbono/terapia , Intoxicación por Gas/complicaciones , Intoxicación por Gas/terapia , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Masculino , Oxígeno , Adulto Joven
20.
ACS Appl Mater Interfaces ; 14(31): 36227-36237, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35912486

RESUMEN

Flexible and stretchable humidity sensors for wearable purposes have become increasingly important in health care and physiological signal monitoring. However, to the authors' knowledge, there is no report on flexible and stretchable paper-based humidity sensors that are low-cost, easily fabricated, and environmentally friendly. In this work, for the first time, we propose a stretchable, textile-compatible paper-based origami humidity sensor (POHS). The POHS can achieve good stretchability by integrating origami folding structures with a paper substrate, in which an airlaid paper acts as both a sensing material and a sensor substrate. This sensor has high sensitivity, good response, and recovery properties with excellent stability during deformation. This sensor has proved to be capable of dynamically monitoring the breathing rate after 300 folding and unfolding cycles. The flexible and stretchable nature of our POHS ensures that it is compatible for textile attachment and its utility for wearable applications, including respiration rate monitoring and diaper wetting detection. The facile fabrication process and convenient disposal method of the POHS proposed in this study provide feasible solutions for the development of low-cost wearable humidity sensors.


Asunto(s)
Dispositivos Electrónicos Vestibles , Electrónica , Humedad , Monitoreo Fisiológico/métodos , Textiles
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