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1.
Cell Mol Biol Lett ; 29(1): 50, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38594618

RESUMEN

BACKGROUND: Melanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma. METHODS: We evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy. RESULTS: Our results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway. CONCLUSION: These findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.


Asunto(s)
Antineoplásicos , Imidazoles , Inmunoconjugados , Melanoma , Oximas , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Neoplasias Cutáneas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Fosfatidilinositol 3-Quinasas , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Inmunoconjugados/genética , Inmunoconjugados/uso terapéutico , Mutación
2.
Opt Express ; 31(11): 17480-17493, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37381480

RESUMEN

Coherent optical links are becoming increasingly attractive for intra-data center applications as data rates scale. Realizing the era of high-volume short-reach coherent links will require substantial improvements in transceiver cost and power efficiency, necessitating a reassessment of conventional architectures best-suited for longer-reach links and a review of assumptions for shorter-reach implementations. In this work, we analyze the impact of integrated semiconductor optical amplifiers (SOAs) on link performance and power consumption, and describe the optimal design spaces for low-cost and energy-efficient coherent links. Placing SOAs after the modulator provide the most energy-efficient link budget improvement, up to 6 pJ/bit for large link budgets, despite any penalties from nonlinear impairments. Increased robustness to SOA nonlinearities makes QPSK-based coherent links especially attractive, and larger supported link budgets enable the inclusion of optical switches, which could revolutionize data center networks and improve overall energy efficiency.

3.
Phys Chem Chem Phys ; 24(16): 9384-9393, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35383793

RESUMEN

The emerging semiconductor boron arsenide (BAs) with high thermal conductivity has attracted much attention recently, due to its promising application to overcome the bottleneck of high-density heat generated in power electronics and optoelectronic devices. In this work, based on first-principles calculations, we find that cubic BAs possesses high intrinsic electron/hole mobilities and the ionized impurity scattering plays a more important role in carrier scattering, compared with other scattering processes. The mobilities can be significantly enhanced by 14.9% and 76.2% for electrons and holes, respectively, by strain engineering. The investigation of the optoelectronic properties of indirect semiconductor cubic BAs by considering the many-body excitonic effects reveals that the contribution from finite-momentum excitons to optical properties is larger for photon energy ranging from 2.25 eV to 3.50 eV, compared with that from zero-momentum excitons. Finally, we observe that the phonon-electron couplings to total lattice thermal conductivities are non-trivial at low temperatures. These findings provide new insight into the transport and optoelectronic properties of cubic BAs, which are beneficial for the acceleration of the application of this revolutionary thermal management material.

4.
PLoS Biol ; 16(7): e2004921, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30001322

RESUMEN

Spicy foods elicit a pungent or hot and painful sensation that repels almost all mammals. Here, we observe that the tree shrew (Tupaia belangeri chinensis), which possesses a close relationship with primates and can directly and actively consume spicy plants. Our genomic and functional analyses reveal that a single point mutation in the tree shrew's transient receptor potential vanilloid type-1 (TRPV1) ion channel (tsV1) lowers its sensitivity to capsaicinoids, which enables the unique feeding behavior of tree shrews with regards to pungent plants. We show that strong selection for this residue in tsV1 might be driven by Piper boehmeriaefolium, a spicy plant that geographically overlaps with the tree shrew and produces Cap2, a capsaicin analog, in abundance. We propose that the mutation in tsV1 is a part of evolutionary adaptation that enables the tree shrew to tolerate pungency, thus widening the range of its diet for better survival.


Asunto(s)
Especias , Tupaia/fisiología , Adaptación Fisiológica , Aminoácidos/genética , Animales , Capsaicina/farmacología , Capsicum , Secuencia Conservada , Mutación/genética , Nociceptores/metabolismo , Canales Catiónicos TRPV/agonistas , Canales Catiónicos TRPV/metabolismo
5.
J Neurovirol ; 26(3): 391-403, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32301037

RESUMEN

Herpes simplex virus type I (HSV-1) infection causes inflammation in the cornea known as herpes simplex virus keratitis (HSK), a common but serious corneal disease. It is not entirely clear whether the virus during recurring infection comes from the trigeminal ganglia or the eye tissue, including the retina and ciliary ganglion. Because the tree shrew is closely related to primates and tree shrew eye anatomic structures are similar to humans, we studied HSV-1 corneal infection in the tree shrew. We found that HSK symptoms closely mimic those found in human HSK showing typical punctiform and dendritic viral keratitis during the acute infection period. Following the HSV-specific lesions, complications such as stromal scarring, corneal thickening (primary infection), opacity, and neovascularization were observed. In the tree shrew model, following ocular inoculation, the cornea becomes infected, and viral protein can be detected using anti-HSV-1 antibodies in the epithelial layer and retina neuronal ganglion cells. The HSV-1 transcripts, ICP0, ICP4, and LAT can be detected at 3 days post-infection (dpi), peaking at 5 dpi. After 2 weeks, ICP4 and ICP0 transcripts are reduced to a basal level, but the Latency Associated Transcripts (LATs) continue to accumulate. Interestingly, after the acute infection, we still detected abundant active HSV-1 in tree shrew eyes. Further, we found HSV-1 persistent in the ciliary ganglion and cornea. These findings are discussed in support of the tree shrew as a non-human primate HSK model, which could be useful for mechanistic studies of HSK.


Asunto(s)
Córnea/virología , Regulación Viral de la Expresión Génica , Herpes Simple/virología , Herpesvirus Humano 1/genética , Queratitis Herpética/virología , Neovascularización Patológica/virología , Animales , Córnea/patología , Modelos Animales de Enfermedad , Femenino , Ganglios Parasimpáticos/patología , Ganglios Parasimpáticos/virología , Herpes Simple/patología , Herpesvirus Humano 1/crecimiento & desarrollo , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/patogenicidad , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Queratitis Herpética/patología , MicroARNs/genética , MicroARNs/metabolismo , Neovascularización Patológica/patología , Neuronas/patología , Neuronas/virología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ganglio del Trigémino/patología , Ganglio del Trigémino/virología , Tupaia , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Latencia del Virus
6.
Chemphyschem ; 21(6): 568-574, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-31773853

RESUMEN

The electron transport properties of polycyclic aromatic hydrocarbons (PAHs) with different numbers of benzene rings tethered to narrow zigzag graphene nanoribbon (ZGNR) electrodes have been investigated. Results show that the transport properties of PAHs are dependent on whether the number of benzene rings in the width direction is odd or even. This effect is strong for narrow width PAHs, but its strength decreases as the width of the PAH is increased. PAHs with an odd number of rings exhibit poor transport properties, whereas the ones having an even number of rings show excellent transport properties coupled with a negative differential resistance (NDR) effect. Moreover, the linkage points and the structure of the molecules have a noticeable effect on the transport properties of the PAH, making the odd-even effect weaker or disappear entirely. Although the PAH with three benzene rings displays poor transport capabilities, it shows excellent rectification behavior compared to the other examined molecules. These studies present a feasible avenue for designing molecular devices with enhanced performance by the careful manipulation of the PAH molecular structure.

7.
Opt Express ; 27(4): 5203-5216, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30876122

RESUMEN

Here we demonstrate an 8x4 multi-wavelength selective ring resonator based crossbar switch matrix implemented in a 220-nm silicon photonics foundry for interconnecting electronic packet switches in scalable data centers. This switch design can dynamically assign up to two wavelength channels for any port-port connection, providing almost full connectivity with significant reduction in latency, cost and complexity. The switch unit cell insertion loss was measured at 0.8 dB, with an out-of-band rejection of 32 dB at 400 GHz channel separation. All the ring resonator heaters were thermally tuned, with heaters controlled by a custom 64-channel DAC driver. Detailed measurements on the whole switch showed standard deviation of 2 dB in losses across different paths, standard deviation of 0.33 nm in resonant wavelength and standard deviation of 0.01 nm/mW in ring heater tuning efficiency. Data transmission experiments at 40 Gbps showed negligible penalty due to crosstalk paths through the switch.

8.
Sensors (Basel) ; 19(18)2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31487933

RESUMEN

: Location information is a key issue for applications of the Internet of Things. In this paper, we focus on mobile wireless networks with moving agents and targets. The positioning process is divided into two phases based on the factor graph, i.e., a prediction phase and a joint self-location and tracking phase. In the prediction phase, we develop an adaptive prediction model by exploiting the correlation of trajectories within a short period to formulate the prediction message. In the joint positioning phase, agents calculate the cooperative messages according to variational message passing and locate themselves. Simultaneously, the average consensus algorithm is employed to realize distributed target tracking. The simulation results show that the proposed prediction model is adaptive to the random movement of nodes. The performance of the proposed joint self-location and tracking algorithm is better than the separate cooperative self-localization and tracking algorithms.

9.
J Virol ; 90(2): 790-804, 2016 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-26512084

RESUMEN

UNLABELLED: Studies of herpes simplex virus (HSV) infections of humans are limited by the use of rodent models such as mice, rabbits, and guinea pigs. Tree shrews (Tupaia belangeri chinensis) are small mammals indigenous to southwest Asia. At behavioral, anatomical, genomic, and evolutionary levels, tree shrews are much closer to primates than rodents are, and tree shrews are susceptible to HSV infection. Thus, we have studied herpes simplex virus 1 (HSV-1) infection in the tree shrew trigeminal ganglion (TG) following ocular inoculation. In situ hybridization, PCR, and quantitative reverse transcription-PCR (qRT-PCR) analyses confirm that HSV-1 latently infects neurons of the TG. When explant cocultivation of trigeminal ganglia was performed, the virus was recovered after 5 days of cocultivation with high efficiency. Swabbing the corneas of latently infected tree shrews revealed that tree shrews shed virus spontaneously at low frequencies. However, tree shrews differ significantly from mice in the expression of key HSV-1 genes, including ICP0, ICP4, and latency-associated transcript (LAT). In acutely infected tree shrew TGs, no level of ICP4 was observed, suggesting the absence of infection or a very weak, acute infection compared to that of the mouse. Immunofluorescence staining with ICP4 monoclonal antibody, and immunohistochemistry detection by HSV-1 polyclonal antibodies, showed a lack of viral proteins in tree shrew TGs during both acute and latent phases of infection. Cultivation of supernatant from homogenized, acutely infected TGs with RS1 cells also exhibited an absence of infectious HSV-1 from tree shrew TGs. We conclude that the tree shrew has an undetectable, or a much weaker, acute infection in the TGs. Interestingly, compared to mice, tree shrew TGs express high levels of ICP0 transcript in addition to LAT during latency. However, the ICP0 transcript remained nuclear, and no ICP0 protein could be seen during the course of mouse and tree shrew TG infections. Taken together, these observations suggest that the tree shrew TG infection differs significantly from the existing rodent models. IMPORTANCE: Herpes simplex viruses (HSVs) establish lifelong infection in more than 80% of the human population, and their reactivation leads to oral and genital herpes. Currently, rodent models are the preferred models for latency studies. Rodents are distant from primates and may not fully represent human latency. The tree shrew is a small mammal, a prosimian primate, indigenous to southwest Asia. In an attempt to further develop the tree shrew as a useful model to study herpesvirus infection, we studied the establishment of latency and reactivation of HSV-1 in tree shrews following ocular inoculation. We found that the latent virus, which resides in the sensory neurons of the trigeminal ganglion, could be stress reactivated to produce infectious virus, following explant cocultivation and that spontaneous reactivation could be detected by cell culture of tears. Interestingly, the tree shrew model is quite different from the mouse model of HSV infection, in that the virus exhibited only a mild acute infection following inoculation with no detectable infectious virus from the sensory neurons. The mild infection may be more similar to human infection in that the sensory neurons continue to function after herpes reactivation and the affected skin tissue does not lose sensation. Our findings suggest that the tree shrew is a viable model to study HSV latency.


Asunto(s)
Herpesvirus Humano 1/fisiología , Transcripción Genética , Ganglio del Trigémino/virología , Tupaiidae/virología , Latencia del Virus , Replicación Viral , Animales , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Herpesviridae , Ratones Endogámicos BALB C , Proteínas Virales/biosíntesis , Esparcimiento de Virus
10.
Opt Lett ; 42(23): 4934-4937, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29216149

RESUMEN

We present an on-chip wavelength reference with a partial drop ring resonator and germanium photodetector. This approach can be used in ring-resonator-based wavelength-selective switches where absolute wavelength alignment is required. We use the temperature dependence of heater resistance as a temperature sensor. Additionally, we discuss locking speed, statistical variation of heater resistances, and tuning speed of the switches.

11.
J Neurovirol ; 22(3): 293-306, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26501779

RESUMEN

Herpes Simplex Virus type I (HSV-1) latently infects peripheral nervous system (PNS) sensory neurons, and its reactivation leads to recurring cold sores. The reactivated HSV-1 can travel retrograde from the PNS into the central nervous system (CNS) and is known to be causative of Herpes Simplex viral encephalitis. HSV-1 infection in the PNS is well documented, but little is known on the fate of HSV-1 once it enters the CNS. In the murine model, HSV-1 genome persists in the CNS once infected through an ocular route. To gain more details of HSV-1 infection in the CNS, we characterized HSV-1 infection of the tree shrew (Tupaia belangeri chinensis) brain following ocular inoculation. Here, we report that HSV-1 enters the tree shrew brain following ocular inoculation and HSV-1 transcripts, ICP0, ICP4, and LAT can be detected at 5 days post-infection (p.i.), peaking at 10 days p.i. After 2 weeks, ICP4 and ICP0 transcripts are reduced to a basal level, but the LAT intron region continues to be expressed. Live virus could be recovered from the olfactory bulb and brain stem tissue. Viral proteins could be detected using anti-HSV-1 antibodies and anti-ICP4 antibody, during the acute stage but not beyond. In situ hybridization could detect LAT during acute infection in most brain regions and in olfactory bulb and brain stem tissue well beyond the acute stage. Using a homogenate from these tissues' post-acute infection, we did not recover live HSV-1 virus, supporting a latent infection, but using a modified explant cocultivation technique, we were able to recover reactivated virus from these tissues, suggesting that the HSV-1 virus latently infects the tree shrew CNS. Compared to mouse, the CNS acute infection of the tree shrew is delayed and the olfactory bulb contains most latent virus. During the acute stage, a portion of the infected tree shrews exhibit symptoms similar to human viral encephalitis. These findings, together with the fact that tree shrews are closely related to primates, provided a valuable alternative model to study HSV-1 infection and pathogenesis in the CNS.


Asunto(s)
Encefalitis por Herpes Simple/virología , Regulación Viral de la Expresión Génica , Herpesvirus Humano 1/genética , Ganglio del Trigémino/virología , Activación Viral , Latencia del Virus , Animales , Tronco Encefálico/metabolismo , Tronco Encefálico/patología , Tronco Encefálico/virología , Modelos Animales de Enfermedad , Encefalitis por Herpes Simple/genética , Encefalitis por Herpes Simple/metabolismo , Encefalitis por Herpes Simple/patología , Femenino , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/patogenicidad , Especificidad del Huésped , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Ratones , Ratones Endogámicos BALB C , MicroARNs/genética , MicroARNs/metabolismo , Bulbo Olfatorio/metabolismo , Bulbo Olfatorio/patología , Bulbo Olfatorio/virología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Técnicas de Cultivo de Tejidos , Ganglio del Trigémino/metabolismo , Ganglio del Trigémino/patología , Tupaiidae , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
12.
Pharm Res ; 31(11): 3201-10, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24831313

RESUMEN

PURPOSE: Pulsatile delivery of proteins, in which release occurs over a short time after a period of little or no release, is desirable for many applications. This paper investigates the effect of biodegradable polymer shell thickness on pulsatile protein release from biodegradable polymer microcapsules. METHODS: Using precision particle fabrication (PPF) technology, monodisperse microcapsules were fabricated encapsulating bovine serum albumin (BSA) in a liquid core surrounded by a drug-free poly(lactide-co-glycolide) (PLG) shell of uniform, controlled thickness from 14 to 19 µm. RESULTS: When using high molecular weight PLG (Mw 88 kDa), microparticles exhibited the desired core-shell structure with high BSA loading and encapsulation efficiency (55-65%). These particles exhibited very slow release of BSA for several weeks followed by rapid release of 80-90% of the encapsulated BSA within 7 days. Importantly, with increasing shell thickness the starting time of the pulsatile release could be controlled from 25 to 35 days. CONCLUSIONS: Biodegradable polymer microcapsules with precisely controlled shell thickness provide pulsatile release with enhanced control of release profiles.


Asunto(s)
Cápsulas/química , Poliglactina 910/química , Proteínas/química , Plásticos Biodegradables/química , Composición de Medicamentos/métodos , Peso Molecular , Tamaño de la Partícula , Polímeros/química , Albúmina Sérica Bovina/química
13.
Heliyon ; 10(4): e25677, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38370207

RESUMEN

Reducing carbon emissions while maintaining simultaneous economic growth has been the focus of agricultural and environmental management research in recent times. To examine the influence of agricultural environmental regulations and related factors on agricultural carbon emissions efficiency, the entropy method was utilized to weigh each index and develop an index system for evaluating agricultural environmental regulations. This study utilizes the Super Slacked-Based Measure model that takes into account undesirable outputs. The research data used spans the years 2010-2019 and covers 31 provinces in China to calculate the efficiency of agricultural carbon emissions. A spatial Durbin model was employed to investigate the influence of environmental regulations and other influential factors on the efficiency of agricultural carbon emissions. The efficiency levels in the eastern region of China have consistently exceeded the national average, whereas the central region has demonstrated the lowest efficiency levels across the nation. Both the efficiency of agricultural carbon emissions and the intensity of agri-environmental regulations measured in this paper are strongly spatially autocorrelated between provinces. The environmental regulations index on local agricultural carbon emissions efficiency is significantly positive, while the effect on the agricultural carbon emissions efficiency in adjacent areas is not significant. Overall, agricultural environmental regulations effectively enhance agricultural carbon emissions efficiency, which in turn promotes technological innovation and economic growth. At the same time, local governments should actively adopt targeted strategies based on the actual situation of different regions in terms of their resource endowments and differences in the production characteristics of different crops.

14.
J Pediatr Urol ; 20(2): 227-236, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38000951

RESUMEN

BACKGROUND: This meta-analysis aimed to evaluate the difference in postoperative complications as urethrocutaneous fistula or glans dehiscence, in children undergoing primary hypospadias repair with caudal block (CB) versus non-caudal block (NCB). METHODS: Data were obtained from MEDLINE, Embase, Web of Science, and the Cochrane Library. Comparative studies of CB versus NCB were identified, with reports of complications published or presented until October 2022. Subgroup analyses were performed based on study type, meatal location (distal only), type of NCB, surgeon and technique, and concentration and dose of anesthetics. RESULTS: Compared to the reference group of NCB, CB was not significantly associated with the development of complications following primary hypospadias repair (OR 1.40, 95 % CI 0.88-2.23). After adjusting for confounding factors, such as type of study(OR 1.51, 95%CI: 0.29-7.91), type of NCB[PB (OR 1.82, 95 % CI: 0.87-3.84), GA (OR 1.26, 95 % CI: 0.39-4.04)], meatal location (distal only) (OR 1.22, 95 % CI: 0.61-2.43), surgeon and technique (OR 1.37, 95 % CI: 0.59-3.14) and concentration and dose of anesthetics(OR 2.74, 95 % CI: 0.82-9.20), subgroup analyses revealed no significant association between CB and NCB (P > 0.05). DISCUSSION: Previous studies have found a correlation between CB and increased incidence of postoperative complications (urethrocutaneous fistula or glans dehiscence) of hypospadias, but different literature have suggested that surgical technique, surgical duration and the severity of hypospadias, rather than CB, are closely related to the occurrence of complications. In order to reduce confounding factors, subgroup analyses were conducted. The results showed that no correlation could be found in postoperative complications and CB. CONCLUSIONS: This meta-analysis compared the incidence of urethrocutaneous fistula or glans dehiscence in the CB and NCB groups for primary hypospadias repair in children, indicating that no clear correlation could be found in postoperative complications and CB. Subgroup analyses on study type, type of NCB, meatal location (distal only), surgeon and technique, and regional anesthetic concentration and dose supported this conclusion.

15.
ACS Nano ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38320191

RESUMEN

The electron-phonon interaction (EPI) and phonon-phonon interactions are ubiquitous in promising two-dimensional (2D) semiconductors, determining both electronic and thermal transport properties. In this work, based on ab initio calculations, the effects of intervalley scattering on EPI and higher-order four-phonon interactions of α-Te and ß-Te are investigated. Through the proposed selection rules for scattering channels and calculations of full electron-phonon scattering rates, we demonstrate that multiple nearly degenerate local valleys/peaks produce more scattering channels, resulting in stronger intervalley scattering over intravalley scattering. The lattice thermal conductivities of α-Te and ß-Te are decreased by as much as 10.9% and 30.8% by considering EPI under the carrier concentration of 2 × 1013 cm-2 (n-type) at 300 K compared to those limited by three-phonon scattering, respectively. However, when further considering four-phonon scattering, EPI reduces the lattice thermal conductivities by 2.6% and 19.4% for α-Te and ß-Te, respectively. Furthermore, it is revealed that the four-phonon interaction is more dominant in phonon transport for α-Te than that for ß-Te due to the presence of an acoustic-optical phonon gap in α-Te. Finally, we demonstrate strong intervalley scattering induces significant renormalization effects from EPI on all the constituent parameters of thermoelectric performance. Our results show the contributions of intervalley scattering to the electronic properties as well as thermal transport properties in band-convergent thermoelectric materials are essential and highlight the potential of monolayer tellurium as a promising candidate for advanced thermoelectric applications.

16.
Adv Sci (Weinh) ; 11(18): e2307691, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38454650

RESUMEN

The 2D semiconductors are an ideal platform for exploration of bosonic fluids composed of coupled photons and collective excitations of atoms or excitons, primarily due to large excitonic binding energies and strong light-matter interaction. Based on first-principles calculations, it is demonstrated that the phonon polaritons formed by two infrared-active phonon modes in monolayer MoSi2N4 and WSi2N4 possess ultra-high confinement factors of around ≈105 and 103, surpassing those of conventional polaritonic thin-film materials by two orders of magnitude. It is observed that the first bright exciton possesses a substantial binding energies of 750 and 740 meV in these two monolayers, with the radiative recombination lifetimes as long as 25 and 188 ns, and the Rabi splitting of the formed cavity-exciton polaritons reaching 373 and 321 meV, respectively. The effective masses of the cavity exciton polaritons are approximately 10-5me, providing the potential for high-temperature quantum condensation. The ultra-confined and ultra-low-loss phonon polaritons, as well as strongly-coupled cavity exciton polaritons with ultra-small polaritonic effective masses in these two monolayers, offering the flexible control of light at the nanoscale, probably leading to practical applications in nanophotonics, meta-optics, and quantum materials.

17.
Int J Psychophysiol ; 191: 1-8, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37348762

RESUMEN

OBJECTIVES: To investigate the changes in sleep quality, heart rate variability (HRV) and resting-state electroencephalogram (rsEEG) in patients with major depressive disorder (MDD), and to explore whether HRV and rsEEG may be served as more convenient tools to assess sleep quality in MDD patients. METHOD: We included a total of 91 subjects (46 healthy controls and 45 MDD patients) and compared their sleep quality, HRV and power spectra of rsEEG. Correlation analyses were conducted to discuss the relationship between HRV and seven factors of PSQI. Multiple linear regression model was used to examine whether absolute band power could predict sleep quality in MDD patients. RESULTS: We found higher PSQI scores and lower levels of HRV in depressive individuals compared with healthy controls. In MDD patients, sleep latency was negatively correlated with RMSSD and HF. Delta, theta, and alpha band power of rsEEG were higher in MDD patients. Regression analyses showed delta band power of TP8, as well as theta, alpha band power of AF3 predicts PSQI score of MDD patients. CONCLUSIONS: The findings of our study show that some aspects of sleep problems had negative correlations with parasympathetic activity and the regression model supports that the band power of rsEEG may be used as a potential indicator to evaluate the sleep quality in MDD patients. SIGNIFICANCE: Cortical hyperarousal may be one of the reasons leading to poor sleep quality of MDD patients. And resting-state EEG can be used as a potential indicator for clinical assessment of MDD patients' sleep quality.


Asunto(s)
Trastorno Depresivo Mayor , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Trastorno Depresivo Mayor/complicaciones , Calidad del Sueño , Electroencefalografía , Análisis de Regresión , Frecuencia Cardíaca/fisiología
18.
Brain Sci ; 13(8)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37626530

RESUMEN

Early adverse life events (EALs) increase susceptibility to depression and impair cognitive performance, but the physiological mechanisms are still unclear. The target of this article is to clarify the impact of adverse childhood experiences on emotional and cognitive performance from the perspective of the heart-brain axis. We used the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to test cognitive function and the Childhood Trauma Questionnaire (CTQ) to assess adverse childhood experiences. Heart rate variability (HRV) and electroencephalograms (EEG) were acquired at rest. We observed that subjects with depression had experienced more traumatic events during their childhood. Furthermore, they exhibited lower heart rate variability and higher power in the delta, theta, and alpha frequency bands. Moreover, heart rate variability partially mediated the association between childhood trauma exposure and depressive symptoms. Our findings suggested that adverse life events in childhood could influence the development of depression in adulthood, which might be linked to cardiac autonomic dysfunction and altered brain function.

19.
Front Plant Sci ; 14: 1201759, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37396636

RESUMEN

Objective: Nutrient resorption efficiency and stoichiometric ratios are important strategies for understanding plants. The present study examined whether or not the nutrient resorption process of plant petals is similar to that of leaves and other vegetative organs, as well as the nutrient restriction status of the whole flowering process of plants in urban ecosystems. Methods: Four Rosaceae tree species, Prunus yedoensis Matsum, Prunus serrulata var. lannesiana, Malus micromalus Makino, and Prunus cerasifera 'Atropurpurea', were selected as urban greening species to analyze the contents of C, N, P, and K elements in the petals and their stoichiometric ratios and nutrient resorption efficiencies. Results: The results show interspecific differences in nutrient contents, stoichiometric ratios, and nutrient resorption efficiency of the fresh petals and petal litter of the four Rosaceae species. The nutrient resorption process was similar to that of the leaves before the petals fell. The nutrient contents of petals were higher than that of leaves at the global level, but the stoichiometric ratio and nutrient resorption efficiency of petals were lower. According to the "relative resorption hypothesis", N was limiting during the entire flowering period. The nutrient resorption efficiency of petals was positively correlated with nutrient variation. The correlation between the nutrient resorption efficiency of petals with nutrient content and stoichiometric ratio of petal litter was stronger. Conclusion: The experimental results provide scientific basis and theoretical support for the selection, scientific maintenance and fertilization management of Rosaceae tree species in urban greening.

20.
J Texture Stud ; 54(3): 394-409, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36111886

RESUMEN

Meat is the main source of protein nutrition for humans. However, given the increasing population and environmental pressure, a shortage of meat is expected in the future. The preparation of plant-based (meat) products using existing processing methods represents a breakthrough to solve the shortage of traditional animal meat in the future, and texture is a key issue determining whether plant-based (meat) products can replace traditional animal meat. Therefore, this review highlights recent progress in the texture of plant-based (meat) products. First, the texture changes in plant-based (meat) products were reviewed based on components (proteins, starch, lipids, food additives) and processing methods (processing factors, instrumental factors). Then, the current methods used to analyze the texture of plant-based (meat) products were summarized based on sensory evaluation and instrumental analysis (mechanical analysis, spectral analysis, and image analysis). Finally, this review outlined methods to improve the texture quality of plant-based (meat) products and analytical evaluation methods and provided an outlook on future research priorities.


Asunto(s)
Aditivos Alimentarios , Carne , Humanos , Animales , Carne/análisis
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