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1.
J Cancer Res Clin Oncol ; 150(2): 34, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277078

RESUMO

PURPOSE: The study aims to develop and validate a combined model for predicting 3-year cancer-specific survival (CSS) in lung cancer patients treated with stereotactic body radiation therapy (SBRT) by integrating clinical and radiomic parameters. METHODS: Clinical data and pre-treatment CT images were collected from 102 patients treated with lung SBRT. Multivariate logistic regression and the least absolute shrinkage and selection operator were used to determine the clinical and radiomic factors associated with 3-year CSS. Three prediction models were developed using clinical factors, radiomic factors, and a combination of both. The performance of the models was assessed using receiver operating characteristic curve and calibration curve. A nomogram was also created to visualize the 3-year CSS prediction. RESULTS: With a 36-month follow-up, 40 patients (39.2%) died of lung cancer and 62 patients (60.8%) survived. Three clinical factors, including gender, clinical stage, and lymphocyte ratio, along with three radiomic features, were found to be independent factors correlated with 3-year CSS. The area under the curve values for the clinical, radiomic, and combined model were 0.839 (95% CI 0.735-0.914), 0.886 (95% CI 0.790-0.948), and 0.914 (95% CI 0.825-0.966) in the training cohort, and 0.757 (95% CI 0.580-0.887), 0.818 (95% CI 0.648-0.929), and 0.843 (95% CI 0.677-0.944) in the validation cohort, respectively. Additionally, the calibration curve demonstrated good calibration performance and the nomogram created from the combined model showed potential for clinical utility. CONCLUSION: A clinical-radiomic model was developed to predict the 3-year CSS for lung cancer patients treated with SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Humanos , Neoplasias Pulmonares/radioterapia , 60570 , Calibragem , Morte
2.
Clin Lung Cancer ; 24(8): e323-e331.e2, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37648569

RESUMO

BACKGROUND: The study aims to identify the risk factors and develop a model for predicting grade ≥2 radiation pneumonitis (RP) for lung cancer patients treated with stereotactic body radiation therapy (SBRT). MATERIALS AND METHODS: Clinical data, dosimetric data, and laboratory biomarkers from 186 patients treated with lung SBRT were collected. Univariate and multivariate logistic regression were performed to determine the predictive factors for grade ≥2 RP. Three models were developed by using the clinical, dosimetric, and combined factors, respectively. RESULTS: With a median follow-up of 36 months, grade ≥2 RP was recorded in 13.4% of patients. On univariate logistic regression analysis, clinical factors of age and lung volume, dosimetric factors of treatment durations, fractional dose and V10, and laboratory biomarkers of neutrophil, PLT, PLR, and Hb levels were significantly associated with grade ≥2 RP. However, on multivariate analysis, only age, lung volume, fractional dose, V10, and Hb levels were independent factors. AUC values for the clinical, dosimetric, and combined models were 0.730 (95% CI, 0.660-0.793), 0.711 (95% CI, 0.641-0.775) and 0.830 (95% CI, 0.768-0.881), respectively. The combined model provided superior discriminative ability than the clinical and dosimetric models (P < .05). CONCLUSION: Age, lung volume, fractional dose, V10, and Hb levels were demonstrated to be significant factors associated with grade ≥2 RP for lung cancer patients after SBRT. A novel model combining clinical, dosimetric factors, and laboratory biomarkers improved predictive performance compared with the clinical and dosimetric model alone.


Assuntos
Neoplasias Pulmonares , Pneumonite por Radiação , Radiocirurgia , Humanos , Neoplasias Pulmonares/cirurgia , Pneumonite por Radiação/diagnóstico , Pneumonite por Radiação/epidemiologia , Pneumonite por Radiação/etiologia , Radiocirurgia/efeitos adversos , Pulmão , Biomarcadores
3.
Cell Oncol (Dordr) ; 46(4): 1049-1067, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37012514

RESUMO

PURPOSE: Gastric cancer (GC) is a malignant tumour with high mortality, and liver metastasis is one of the main causes of poor prognosis. SLIT- and NTRK-like family member 4 (SLITRK4) plays an important role in the nervous system, such as synapse formation. Our study aimed to explore the functional role of SLITRK4 in GC and liver metastasis. METHODS: The mRNA level of SLITRK4 was evaluated using publicly available transcriptome GEO datasets and Renji cohort. The protein level of SLITRK4 in the tissue microarray of GC was observed using immunohistochemistry. Cell Counting Kit-8, colony formation, transwell migration assays in vitro and mouse model of liver metastasis in vivo was performed to investigate the functional roles of SLITRK4 in GC. Bioinformatics predictions and Co-IP experiments were applied to screen and identify SLITRK4-binding proteins. Western blot was performed to detect Tyrosine Kinase receptor B (TrkB)-related signaling molecules. RESULTS: By comparing primary and liver metastases from GC, SLITRK4 was found to be upregulated in tissues of GC with liver metastasis and to be closely related to poor clinical prognosis. SLITRK4 knockdown significantly abrogated the growth, invasion, and metastasis of GC in vitro and in vivo. Further study revealed that SLITRK4 could interact with Canopy FGF Signalling Regulator 3 (CNPY3), thus enhancing TrkB- related signaling by promoting the endocytosis and recycling of the TrkB receptor. CONCLUSION: In conclusion, the CNPY3-SLITRK4 axis contributes to liver metastasis of GC according to the TrkB-related signaling pathway. which may be a therapeutic target for the treatment of GC with liver metastasis.


Assuntos
Neoplasias Hepáticas , Neoplasias Gástricas , Animais , Camundongos , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , Transdução de Sinais , Neoplasias Hepáticas/patologia , Endocitose , Proliferação de Células/genética
4.
Materials (Basel) ; 16(7)2023 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-37048917

RESUMO

High-temperature body-centered cubic (BCC) γ-U is effectively stablized by γ-(U,Zr) alloys that also make it feasible to use it as a nuclear fuel. However, relatively little research has focused on γ-(U,Zr) alloys due to their instability at room temperature. The effect of Zr composition on its mechanical properties is not clear yet. Herein, we perform molecular dynamics simulations to investigate the mechanical and dynamical stabilities of γ-(U,Zr) alloys under high temperatures, and we calculate the corresponding lattice constants, various elastic moduli, Vickers hardness, Debye temperature, and dynamical structure factor. The results showed that γ-U, ß-Zr, and γ-(U,Zr) are all mechanically and dynamically stable at 1200 K, which is in good agreement with the previously reported high-temperature phase diagram of U-Zr alloys. We found that the alloying treatment on γ-U with Zr can effectively improve its mechanical strength and melting points, such as Vickers hardness and Debye temperature, making it more suitable for nuclear reactors. Furthermore, the Zr concentrations in γ-(U,Zr) alloys have an excellent effect on these properties. In addition, the dynamical structure factor reveals that γ-U shows different structural features after alloying with Zr. The present simulation data and insights could be significant for understanding the structures and properties of UZr alloy under high temperatures.

5.
Small ; 19(18): e2300419, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36725302

RESUMO

All-Mn-based Li-rich cathodes Li2 MnO3 have attracted extensive attention because of their cost advantage and ultrahigh theoretical capacity. However, the unstable anionic redox reaction (ARR), which involves irreversible oxygen releases, causes declines in cycling capacity and intercalation potential, thus hindering their practical applications. Here, it is proposed that introducing stacking-fault defects into the Li2 MnO3 can localize oxygen lattice evolutions and stabilize the ARR, eliminating oxygen releases. The thus-made cathode has a highly reversible capacity (320 mA h g-1 ) and achieves excellent cycling stability. After 100 cycles, the capacity retention rate is 86% and the voltage decay is practically eliminated at 0.19 mV per cycle. Attributing to the stable ARR, samples show reduced stress-strain and phase transitions. Neutron pair distribution function (nPDF) measurements indicate that there is a structure response of localized oxygen lattice distortion to the ARR and the average oxygen lattice framework is well-preserved which is a prerequisite for the high cycle reversibility.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-986036

RESUMO

In this paper, the clinical data of a case of accidental poisoning of dimethylformamide in a traffic accident was analyzed. The patient was trapped in the driving room, his limbs were soaked in dimethylformamide for a long time, and dimethylformamide was inhaled at the same time. After 4 days of treatment in a local hospital, he was transferred to the Department of Poisoning & Occupational Diseases, Emergency Medicine of Qilu Hospital of Shandong University for treatment. The main clinical manifestation of the patient was liver damage and intractable abdominal pain, which was cured by active treatment.


Assuntos
Masculino , Humanos , Dimetilformamida , Dor Abdominal , Doenças Profissionais/complicações , Intoxicação
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979217

RESUMO

ObjectiveTo establish a mutation library of rifampicin resistance gene rpoB. MethodsThe ΔrpoB attB::rpoB strain of Mycobacterium smegmatis (M. smegmatis) be constructed by homologous recombination and L5 attB phage integration site exchange. Based on the L5 attB plasmid exchange system and resistance selection medium, 48 clones are selected to verify plasmid replacement efficiency. Degenerate primers are designed every 3 bases in the rifampicin resistance determining region (RRDR), and a full-coverage mutation library of 81 bases in RRDR region is obtained by PCR amplification. The library fragments are seamlessly cloned into the vector and transformed into Escherichia coli (E. coli)to form an E. coli mutation library. Based on the principle of plasmid exchange, the mutant plasmid library is transformed into the M. smegmatis strain ΔrpoB attB::rpoB, and the original L5 attB site plasmid is replaced to form the M. smegmatis mutant library. The genotype of the library are determined by genome extraction, library construction and high-throughput sequencing. ResultsCompared with the wild-type rpoB gene (5 600 bp), the amplified fragment of the rpoB knockout strain is 2 200 bp, which proved that the ΔrpoB attB::rpoB conditional knockout strain of M. smegmatis is successfully constructed. The success rate of plasmid replacement is 100%. There were 540 kinds of single amino acid mutations in both E. coli library and M. smegmatis library, 5 301 kinds of multi-point mutations in E. coli library, and 853 kinds of multi-point mutations in M. smegmatis library. The correlation coefficient between E. coli library and M. smegmatis library is 0.84. ConclusionsWe have developed a strategy to construct a library of mutants targeting the essential mycobacterial gene rpoB, and successfully established a mutant library of rifampicin resistance gene rpoB.

8.
Phys Chem Chem Phys ; 25(1): 580-589, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36484277

RESUMO

Theoretically and experimentally, MXenes consisting of Mo and C have aroused much interest due to superconductivity in their films and even monolayer forms. Here, based on first-principles calculations, we systematically calculate the electronic structure, phonon dispersion, and electron-phonon coupling (EPC) of monolayer Mo2C (both T- and H-phases), Mo3C2, and Mo3C3. The results show that H-MoxCy (x = 2 or 3, y = 1-3) always have lower total energies than their corresponding T phase and other configurations. All these two-dimensional (2D) molybdenum carbides are metals and some of them display weak phonon-mediated superconductivity at different superconducting transition temperatures (Tc). The Mo 4d-orbitals play a critical role in their electronic properties and the Mo atomic vibrations play a dominant role in their low-frequency phonons, EPC, and superconductivity. By comparison, we find that increasing the Mo content can enhance the EPC and Tc. Besides, we further explore the impact of strain engineering on their superconducting related physical quantities. With increasing biaxial stretching, the phonon dispersions are gradually softened to form some soft modes, which can trigger some peaks of α2F(ω) in the low-frequency region and evidently increase the EPC λ. The Tc of H-Mo2C can be increased up to 11.79 K. Upon further biaxial stretching, charge density waves may appear in T-Mo2C, H-Mo3C2, and H-Mo3C3.

9.
Materials (Basel) ; 15(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36363044

RESUMO

At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance.

10.
World J Clin Cases ; 10(28): 10201-10207, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36246832

RESUMO

BACKGROUND: Pipeline dredging agents are new household deep cleaning products used to dredge blockages in kitchen and bathroom pipeline caused by grease, hair, vegetable residue, paper cotton fibre, and other organic substances. Pipeline dredging agents are corrosive chemicals that can cause poisoning through corrosive damage to the digestive tract; however, this has not been reported clinically. Therefore, this report emphasises that oral pipeline dredging agent poisoning can cause corrosive damage to the digestive tract and may have serious health consequences. CASE SUMMARY: A 68-year-old man consumed liquor (200 mL) at approximately 13:00 on April 22, 2021. At approximately 16:00, his family found him unresponsive with blackened lips, blood spots in the corners of the mouth, and blood stains on the ground, as well as an empty bottle of a pipeline dredging agent. One hour later, he was admitted to the emergency department of a local hospital. Considering the empty bottle, he was suspected to have sustained severe corrosive damage to the digestive tract and was transferred to our department at 23:15 on April 22, 2021. He developed dysphagia and intermittent fever and experienced difficulty in opening his mouth throughout his hospital stay. The patient's condition gradually stabilised. However, he suddenly developed respiratory failure on day 12, and endotracheal intubation and ventilator-assisted ventilation were performed. However, the patient died after 1.5 h despite emergency rescue efforts. CONCLUSION: Pipeline dredging agents are highly corrosive and may cause corrosive damage to the digestive tract and asphyxia upon consumption.

11.
Phys Chem Chem Phys ; 24(35): 21261-21269, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36040434

RESUMO

In layered materials with the stacking axis perpendicular to the basal plane, anharmonicity strongly affects phonon propagation due to weak interlayer coupling, which is helpful to reduce the lattice thermal conductivity and improve the thermoelectric (TE) performance significantly. By combining first-principles calculations and the Boltzmann transport equation, we systematically analyzed and evaluated the lattice thermal conductivity and TE properties of LaMOCh (M = Cu, Ag; Ch = S, Se). The results indicate that these layered materials exhibit ultralow lattice thermal conductivities of 0.24-0.37 W m-1 K-1 along the interlayer direction at room temperature. The low lattice thermal conductivities have been analyzed from some inherent phonon properties, such as low acoustic phonon group velocity, large Grüneisen parameters, and a short phonon relaxation time. Originating from their natural layered crystal structure, the thermal and electronic transports (i.e., thermal conductivity, Seebeck coefficient, and electrical conductivity) are both highly anisotropic between their intralayer and interlayer directions. Finally, we obtained ZT values of 1.17 and 1.26 at 900 K along the interlayer direction for n-type LaCuOSe and LaAgOSe, respectively. Generally, LaMOSe exhibit larger anisotropy than LaMOS, in both n- and p-types of doping. Our findings of low thermal conductivities and large anisotropic TE performances of these layered systems should stimulate much attention in BiCuOSe and alike layered TE families.

12.
Oper Neurosurg (Hagerstown) ; 23(4): 334-341, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36001745

RESUMO

BACKGROUND: MRI-guided laser interstitial thermal therapy (MRgLITT) is a novel treatment modality for focal cortical dysplasia (FCD). However, identifying the location and extent of subtle FCD by visual analysis during MRgLITT remains challenging. OBJECTIVE: To introduce voxel-based morphometric MRI postprocessing into the procedure of MRgLITT for FCD-suspected lesions and assess the complementary value of the MRI postprocessing technique for the trajectory design and thermal parameter setting of MRgLITT. METHODS: Junction and normalized fluid-attenuated inversion recovery signal intensity images were used to detect the gray-white matter junction blurring and cortical fluid-attenuated inversion recovery hyperintensity, respectively. According to the 2 postprocessing images, the region of interest (ROI) for ablation was drawn. The main principle of presurgical planning is that the trajectory of the laser fiber was designed as far as possible along the long axis of the ROI while the extent of planned ablation covered the entire ROI. The subsequent intraoperative procedure was performed under the guidance of the presurgical plan. RESULTS: Nine patients with epilepsy with FCD-suspected lesions underwent MRgLITT with the assistance of MRI postprocessing images. Among them, 4 patients were junction positive, 2 patients were normalized fluid-attenuated inversion recovery signal intensity positive, and the remaining 3 patients were positive for both. Postsurgical MRI demonstrated that the ROIs were ablated entirely in 7 patients. Engel Ia, Ib, and IV scores were obtained at 1-year follow-up for 6, 1, and 2 patients, respectively. CONCLUSION: MRI postprocessing provides complementary information for designing the laser fiber trajectory and subsequent ablation for FCDs.


Assuntos
Epilepsia , Terapia a Laser , Malformações do Desenvolvimento Cortical , Epilepsia/cirurgia , Humanos , Lasers , Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/cirurgia
13.
Phys Chem Chem Phys ; 24(30): 18419-18426, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35880864

RESUMO

Materials with superconductivity and a nontrivial band structure near the Fermi level are promising candidates in realizing topological superconductivity. Using first-principles calculations, we systematically investigated the stability, mechanical properties, superconductivity, electronic structures, and topological states of hexagonal TaC and NbC. The results show that they are stable and have excellent mechanical properties. We predicted that these two carbides are strong electron-phonon coupling superconductors with superconducting transition temperatures of 14.8 and 17.1 K, respectively. Strong coupling is mainly dominated by in-plane Ta/Nb atomic vibrations and in-plane Ta/Nb-dxy/dx2-y2 electronic orbitals. The electronic structure calculations demonstrate that a nodal line and a triply degenerate point coexist when not including the spin-orbit coupling (SOC) effect. After including the SOC effect, the nodal line is gapped. The complicated surface states are also calculated and need further experiments to verify. The present results indicate that the hexagonal TaC and NbC are potential candidates as topological superconductors, and pave the way towards exploring the superconductivity and topological materials in condensed matter systems.

14.
Nanoscale ; 14(27): 9754-9761, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35766045

RESUMO

Monolayer borophenes tend to be easily oxidized, while thicker borophenes have stronger antioxidation properties. Herein, we proposed four novel metallic boron crystals by stacking the experimentally synthesized borophenes, and one of the crystals has been reported in our previous experiments. Bilayer units tend to act as blocks for crystals as determined by bonding analyses. Their kinetic, thermodynamic and mechanical stabilities are confirmed by our calculated phonon spectra, molecular dynamics and elastic constants. Our proposed allotropes are more stable than the boron α-Ga phase below 1000 K at ambient pressure. Some of them become more stable than the α-rh or γ-B28 phases at appropriate external pressure. More importantly, our calculations show that three of the proposed crystals are phonon-mediated superconductors with critical temperatures of about 5-10 K, higher than those of most superconducting elemental solids, in contrast to typical boron crystals with significant band gaps. Our study indicates a novel preparation method for metallic and superconducting boron crystals dispensing with high pressure.

15.
Nano Lett ; 22(13): 5592-5599, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35729076

RESUMO

The number of semiconducting MXenes with direct band gaps is extremely low; thus, it is highly desirable to broaden the MXene family beyond carbides and nitrides to expand the palette of desired chemical and physical properties. Here, we theoretically report the existence of the single-layer (SL) dititanium oxide 2H-Ti2O MOene (MXene-like 2D transition oxides), showing an Ising superconducting feature. Moreover, SL halogenated 2H- and 1T-Ti2O monolayers display tunable semiconducting features and strong light-harvesting ability. In addition, the external strains can induce Weyl fermions via quantum phase transition in 2H-Ti2OF2 and Ti2OCl2 monolayers. Specifically, 2H- and 1T-Ti2OF2 are direct semiconductors with band gaps of 0.82 and 1.18 eV, respectively. Furthermore, the carrier lifetimes of SL 2H- and 1T-Ti2OF2 are evaluated to be 0.39 and 2.8 ns, respectively. This study extends emerging phenomena in a rich family of 2D MXene-like MOene materials, which provides a novel platform for next-generation optoelectronic and photovoltaic fields.

16.
Materials (Basel) ; 15(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683314

RESUMO

Strain engineering has attracted extensive attention as a valid method to tune the physical and chemical properties of two-dimensional (2D) materials. Here, based on first-principles calculations and by solving the semi-classical Boltzmann transport equation, we reveal that the tensile strain can efficiently enhance the thermoelectric properties of the GeS2 monolayer. It is highlighted that the GeS2 monolayer has a suitable band gap of 1.50 eV to overcome the bipolar conduction effects in materials and can even maintain high stability under a 6% tensile strain. Interestingly, the band degeneracy in the GeS2 monolayer can be effectually regulated through strain, thus improving the power factor. Moreover, the lattice thermal conductivity can be reduced from 3.89 to 0.48 W/mK at room temperature under 6% strain. More importantly, the optimal ZT value for the GeS2 monolayer under 6% strain can reach 0.74 at room temperature and 0.92 at 700 K, which is twice its strain-free form. Our findings provide an exciting insight into regulating the thermoelectric performance of the GeS2 monolayer by strain engineering.

17.
Sensors (Basel) ; 22(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35632054

RESUMO

Slip-induced falls, responsible for approximately 40% of falls, can lead to severe injuries and in extreme cases, death. A large foot-floor contact angle (FFCA) during the heel-strike event has been associated with an increased risk of slip-induced falls. The goals of this feasibility study were to design and assess a method for detecting FFCA and providing cues to the user to generate a compensatory FFCA response during a future heel-strike event. The long-term goal of this research is to train gait in order to minimize the likelihood of a slip event due to a large FFCA. An inertial measurement unit (IMU) was used to estimate FFCA, and a speaker provided auditory semi-real-time feedback when the FFCA was outside of a 10-20 degree target range following a heel-strike event. In addition to training with the FFCA feedback during a 10-min treadmill training period, the healthy young participants completed pre- and post-training overground walking trials. Results showed that training with FFCA feedback increased FFCA events within the target range by 16% for "high-risk" walkers (i.e., participants that walked with more than 75% of their FFCAs outside the target range) both during feedback treadmill trials and post-training overground trials without feedback, supporting the feasibility of training FFCA using a semi-real-time FFCA feedback system.


Assuntos
Acidentes por Quedas , Marcha , Acidentes por Quedas/prevenção & controle , Fenômenos Biomecânicos , Estudos de Viabilidade , Retroalimentação , Marcha/fisiologia , Humanos
18.
Sensors (Basel) ; 22(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35591203

RESUMO

Intensive balance and coordination training is the mainstay of treatment for symptoms of impaired balance and mobility in individuals with hereditary cerebellar ataxia. In this study, we compared the effects of home-based balance and coordination training with and without vibrotactile SA for individuals with hereditary cerebellar ataxia. Ten participants (five males, five females; 47 ± 12 years) with inherited forms of cerebellar ataxia were recruited to participate in a 12-week crossover study during which they completed two six-week blocks of balance and coordination training with and without vibrotactile SA. Participants were instructed to perform balance and coordination exercises five times per week using smartphone balance trainers that provided written, graphic, and video guidance and measured trunk sway. The pre-, per-, and post-training performance were assessed using the Scale for the Assessment and Rating of Ataxia (SARA), SARAposture&gait sub-scores, Dynamic Gait Index, modified Clinical Test of Sensory Interaction in Balance, Timed Up and Go performed with and without a cup of water, and multiple kinematic measures of postural sway measured with a single inertial measurement unit placed on the participants' trunks. To explore the effects of training with and without vibrotactile SA, we compared the changes in performance achieved after participants completed each six-week block of training. Among the seven participants who completed both blocks of training, the change in the SARA scores and SARAposture&gait sub-scores following training with vibrotactile SA was not significantly different from the change achieved following training without SA (p>0.05). However, a trend toward improved SARA scores and SARAposture&gait sub-scores was observed following training with vibrotactile SA; compared to their pre-vibrotacile SA training scores, participants significantly improved their SARA scores (mean=−1.21, p=0.02) and SARAposture&gait sub-scores (mean=−1.00, p=0.01). In contrast, no significant changes in SARA scores and SARAposture&gait sub-scores were observed following the six weeks of training without SA compared to their pre-training scores immediately preceding the training block without vibrotactile SA (p>0.05). No significant changes in trunk kinematic sway parameters were observed as a result of training (p>0.05). Based on the findings from this preliminary study, balance and coordination training improved the participants' motor performance, as captured through the SARA. Vibrotactile SA may be a beneficial addition to training regimens for individuals with hereditary cerebellar ataxia, but additional research with larger sample sizes is needed to assess the significance and generalizability of these findings.


Assuntos
Ataxia Cerebelar , Transtornos Neurológicos da Marcha , Modalidades de Fisioterapia , Transtornos das Sensações , Adulto , Ataxia Cerebelar/etiologia , Ataxia Cerebelar/terapia , Estudos Cross-Over , Retroalimentação , Feminino , Marcha , Transtornos Neurológicos da Marcha/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural , Autocuidado , Transtornos das Sensações/terapia , Smartphone/instrumentação , Telerreabilitação/instrumentação , Tato , Vibração
19.
Materials (Basel) ; 15(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35591480

RESUMO

Using density functional theory and semiclassical Boltzmann transport equation, the lattice thermal conductivity and electronic transport performance of monolayer SnI2 were systematically investigated. The results show that its room temperature lattice thermal conductivities along the zigzag and armchair directions are as low as 0.33 and 0.19 W/mK, respectively. This is attributed to the strong anharmonicity, softened acoustic modes, and weak bonding interactions. Such values of the lattice thermal conductivity are lower than those of other famous two-dimensional thermoelectric materials such as MoO3, SnSe, and KAgSe. The two quasi-degenerate band valleys for the valence band maximum make it a p-type thermoelectric material. Due to its ultralow lattice thermal conductivities, coupled with an ultrahigh Seebeck coefficient, monolayer SnI2 possesses an ultrahigh figure of merits at 800 K, approaching 4.01 and 3.34 along the armchair and zigzag directions, respectively. The results indicate that monolayer SnI2 is a promising low-dimensional thermoelectric system, and would stimulate further theoretical and experimental investigations of metal halides as thermoelectric materials.

20.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35459000

RESUMO

Vibrotactile sensory augmentation (SA) decreases postural sway during real-time use; however, limited studies have investigated the long-term effects of training with SA. This study assessed the retention effects of long-term balance training with and without vibrotactile SA among community-dwelling healthy older adults, and explored brain-related changes due to training with SA. Sixteen participants were randomly assigned to the experimental group (EG) or control group (CG), and trained in their homes for eight weeks using smart-phone balance trainers. The EG received vibrotactile SA. Balance performance was assessed before, and one week, one month, and six months after training. Functional MRI (fMRI) was recorded before and one week after training for four participants who received vestibular stimulation. Both groups demonstrated significant improvement of SOT composite and MiniBESTest scores, and increased vestibular reliance. Only the EG maintained a minimal detectable change of 8 points in SOT scores six months post-training and greater improvements than the CG in MiniBESTest scores one month post-training. The fMRI results revealed a shift from activation in the vestibular cortex pre-training to increased activity in the brainstem and cerebellum post-training. These findings showed that additional balance improvements were maintained for up to six months post-training with vibrotactile SA for community-dwelling healthy older adults.


Assuntos
Equilíbrio Postural , Vestíbulo do Labirinto , Idoso , Nível de Saúde , Humanos , Vida Independente , Equilíbrio Postural/fisiologia , Smartphone
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