Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 167
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Microsc ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38924561

RESUMO

This study investigates the influence of the sample inherent temperature on the line-scan profile for a silicon trapezoid line with different sidewall angles by Monte-Carlo simulation. This study demonstrates that the profile varies with temperature, particularly focusing on the 'shoulder', which becomes more pronounced with larger sidewall angles. The contrast of the secondary electron profile increases at low primary electron energy but decreases at relatively high PE energy as the temperature rises. The trend of the backscattering electron profile is similar but less noticeable. The underlying mechanism is discussed in detail. This study has potential to provide valuable insights into thermometry in nanostructures using SEMs.

2.
World J Urol ; 42(1): 62, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38285266

RESUMO

PURPOSE: To evaluate the cooling effect and other advantages of a novel circulation system for ureteroscopic holmium laser lithotripsy (URSL) in a standardized in vitro model. MATERIALS AND METHODS: The novel circulation system was assembled by connecting a 4Fr ureteral catheter and a filter. Trails were divided into a new URSL group and a conventional URSL group. First, different power settings (18-30 W) of the holmium laser and irrigation flow rates (20-50 mL/min) were used to evaluate the thermal effect on the lithotripsy site of all groups. Then, renal pelvic temperature and pressure were assessed during URSL at a power of 1.5 J/20 Hz and irrigation flow rates of (20-50 mL/min). Finally, the whole process of lithotripsy was performed at 1.5 J/20 Hz (operator duty cycle ODC: 50%) with an irrigation flow rate of 30 mL/min. The time required for lithotripsy, visual field clarity, and stone migration were observed. RESULTS: Temperature of the lithotripsy point was significantly lower in the new URSL group than in the conventional group (P < 0.05) with irrigation rates (20, 30 mL/min). The renal pelvic pressure of the new group was significantly lower than that of the conventional group in which intrarenal hypertension developed at an irrigation rate of 50 ml/min. The new group had better visual clarity and lesser stone upward migration when lithotripsy was performed at 1.5 J/20 Hz and 30 ml/min. CONCLUSION: The novel circulation system is more effective in reducing the thermal effects of URSL, pelvic pressure, stone upward migration, and improving the visual clarity of the operative field.


Assuntos
Hipertensão , Litotripsia a Laser , Litotripsia , Humanos , Ureteroscopia , Hólmio
3.
Angew Chem Int Ed Engl ; : e202412637, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044283

RESUMO

The dynamic structure evolution of heterogeneous catalysts during reaction has gained great attention recently. However, controllably manipulating dynamic process and then feeding back catalyst design to extend the lifetime remains challenging. Herein, we proposed an entropy variation strategy to develop a dynamic CuZn-Co/HEOs catalyst, in which the non-active Co nano-islands play a crucial role in controlling thermal effect via timely capturing and utilizing reaction heat generated on the adjacent active CuZn alloys, thus solving the deactivation problem of Cu-based catalysts. Specifically, heat sensitive Co nano-islands experienced an entropy increasing process of slowly redispersion during the reaction. Under such heat dissipation effect, the CuZn-Co/HEOs catalyst exhibited 95.7% ethylene selectivity and amazing long-term stability (>530 h) in the typical exothermic acetylene hydrogenation. Aiming at cultivating it as a catalyst with promising industrial potential, we proposed a simple regeneration approach via an entropy decreasing process.

4.
Small ; 19(52): e2306351, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635121

RESUMO

Ni-rich layered oxide cathode materials demonstrate high energy densities for Li-ion batteries, but the electrochemically driven thermal runaway and mechanical degradation remain their long-standing challenges in practical applications. Herein, it presents a novel ZrV2 O7  (ZVO) coating with negative thermal expansion properties along the secondary particles and primary particle grain boundaries (GBs), to simultaneously enhance the structural and thermal stability of LiNi0.8 Co0.1 Mn0.1 O2 (NCM811). It unveils that, such an architecture can significantly enhance the electronic conductivity, suppress the microcracks of GBs, alleviate the layered to spinel/rock-salt phase transformation, and meanwhile relieve the lattice oxygen loss by increasing the oxygen vacancy formation energy increased (1.43 vs 1.90 eV). Consequently, the ZVO-coated NCM811 material demonstrates a remarkable cyclability with 86.5% capacity retention after 100 cycles, and an outstanding rate performance of 30 C under a high-voltage of 4.6 V, outperforming the state-of-the-art literature. More importantly, the Li+ transportation can be readily blocked at 120 °C by the negative-thermal-expansion ZVO coating, thus avoiding the high-temperature thermal runaway.

5.
Nanotechnology ; 34(28)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37019098

RESUMO

Silicon-based gallium nitride lasers are considered potential laser sources for on-chip integration. However, the capability of on-demand lasing output with its reversible and wavelength tunability remains important. Herein, a Benz-shaped GaN cavity is designed and fabricated on a Si substrate and coupled to a Ni metal wire. Under optical pumping, excitation position-related lasing and exciton combination properties of pure GaN cavity are studied systematically. Under electrically driven, joule thermal of Ni metal wire makes it easy to change the temperature of the cavity. And then, we demonstrate a joule heat-induced contactless lasing mode manipulation in the coupled GaN cavity. The driven current, coupling distance, and excitation position influence the wavelength tunable effect. Compared with other positions, the outer ring position has the highest lasing properties and lasing mode tuning abilities. The optimized structures demonstrate clear wavelength tuning and an even mode switch. The thermal reduction of the band gap is identified to account for the modification of the lasing profile, but the thermo-optic effect is non-negligible under a high-driven current.

6.
Surg Endosc ; 37(5): 4084-4087, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36959398

RESUMO

BACKGROUND: Improving oncological curability and preserving urinary function must be established in robotic total mesorectal excision (TME) for rectal cancer. To achieve this, it is important to avoid nerve injury by sharp dissection of the avascular plane by the monopolar device and thermal spread. The aim of this study was to improve the robotic TME quality by focusing on the theory of fundamental use of surgical energy (FUSE) of the monopolar device and investigating the surgical procedure. METHODS: In this single-center retrospective study, 26 consecutive patients who underwent robotic TME for rectal cancer at Tokyo Medical University Hospital between June 2022 and August 2022 were included. All surgeries were performed by FUSE-certified surgeons in accordance with FUSE theory, which was, thermal effect = current density (current/area) squared × tissue resistance × contact time. RESULT: The median age of the patients was 64 years (range 40-79 years), and 17 patients were male. The median operative time was 287 min (range 229-430 min); median bleeding volume, 22 ml (range 5-223 ml); and the median number of harvested lymph nodes, 17 (range 4-40). The conversion rate to open surgery was 0%. A breakdown of Clavien-Dindo classification Grade ≥ II post-operative complications was as follows: surgical site infection, one patient (3.8%); ileus, one patient (3.8%); and urinary dysfunction, one patient (3.8%). No surgery-related or in-hospital deaths occurred. The pathological positive resection margin was not observed. CONCLUSIONS: Robotic TME for rectal cancer based on the theory of FUSE can be safely performed, making it a promising surgical procedure. It is suggested that robotic surgeons acquire surgical operation skills with monopolar devices based on the principles of FUSE, which may lead to an increased quality of robotic TME.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento , Estudos Retrospectivos , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia
7.
Skin Res Technol ; 29(3): e13305, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36973985

RESUMO

BACKGROUND: Laser technology has been widely used in the treatment of hypertrophic scar (HPS). Due to the lack of effective quantitative relationship between laser doses and thermal effect of lesion tissue, the selection of laser doses in clinical laser treatment of HPS is blind, which cannot guarantee the best treatment effect. MATERIALS AND METHODS: The photothermal model of HPS was established by using finite element method. The effects of laser dose parameters such as laser energy density, pulse width, and spot diameter on the thermal effects of laser treatment were analyzed. According to tissue temperature threshold and thermal damage degree of the simulation results, the optimal laser doses of HPS were selected for the laser treatment experiments of rabbit ear HPSs to verify the rationality of the quantitative photothermal model. RESULTS: The temperature rise and thermal damage degree of HPS following laser treatment were directly correlated to the laser doses, which grew with the increase of energy density and laser pulse width. For the different spot diameters, the temperature rise decreased with the increase of spot diameter, whereas the thermal damage degree worsened with the increase of spot diameter. Both simulation and experimental results show that the optimal treatment parameters of HPS were as follows: The laser energy density was 7.5 J/cm3 , the pulse width was 4 ms, and the spot diameter was 7 mm. CONCLUSION: The laser dose parameters optimized by the photothermal model have achieved good therapeutic effects in the rabbit ear HPS, indicating that the model can be used for quantitative evaluation of laser doses before clinical treatment.


Assuntos
Cicatriz Hipertrófica , Terapia a Laser , Terapia Fototérmica , Animais , Coelhos , Cicatriz Hipertrófica/radioterapia , Cicatriz Hipertrófica/terapia , Terapia a Laser/métodos , Temperatura , Terapia Fototérmica/métodos , Temperatura Alta
8.
Food Microbiol ; 111: 104208, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36681392

RESUMO

Induced electric field (IEF), as an alternative non-conventional processing technique, is utilized to sterilize liquid foods. In this study, the survival and sublethal injury of S. aureus under IEF were investigated in 0.85% normal saline, and the inactivation mechanism of IEF was expounded. The plate count results showed that the sublethal injury rates remained above 90% after IEF treatment for more than 8.4 s, and 7.1 log CFU/mL of S. aureus was completely inactivated after 14 s IEF treatment. Scanning electron microscopy and transmission electron microscope images showed that IEF caused the destruction of cell membrane and internal substructure, and the damage to intracellular substructure was more severe. Altered membrane integrity or permeability was demonstrated through flow cytometry and confocal laser scanning microscope analysis, and the different damage to cells was quantified by propidium iodide & 5-carboxy fluorescein diacetate single and double staining. In addition, IEF treatment also decreased the membrane potential and esterase activity of S. aureus cells. Putative inactivation mechanism of IEF against S. aureus is a complex process, and its apoptosis is the result of the combination of several factors, which provide a basis for understanding the inactivation mechanism of IEF.


Assuntos
Anti-Infecciosos , Staphylococcus aureus , Staphylococcus aureus/fisiologia , Membrana Celular , Microscopia Eletrônica de Varredura
9.
Lasers Med Sci ; 38(1): 263, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37952038

RESUMO

The objective of this study was to describe the histological artifacts caused by high-power laser use compared to cold scalpel surgery in oral soft tissue lesions. Clinical studies that evaluated and compared histological artifacts resulting from the use of high-power lasers and cold scalpels in oral soft tissue lesions biopsies were retrieved from seven databases and four grey literatures, up to July 2022. The risk of bias was investigated using the ROBINS-I tool. The certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Seven studies were eligible for qualitative analysis. Based on the results obtained, those four studies had a low risk of bias, and three studies had an unclear risk of bias. The certainty of the evidence was classified as low. Limited evidence showed that epithelial artifacts such as loss of intraepithelial and subepithelial adhesions, accompanied by pyknotic, fusiform, and/or hyperchromic nuclei, were more common when a high-power laser device was used. Four articles reported that the use of high-power lasers did not interfere with the histopathological diagnosis of oral soft tissue lesions. Due to the heterogeneity of the data, a meta-analysis was not performed. Compared to the use of cold scalpels, histological artifacts, particularly those observed in epithelial tissue, are more common when high-powered lasers are used in oral lesions biopsies. The eligibility criteria and adequate indications of high-power lasers in different oral soft tissue lesion treatments must be respected to avoid tissue artifacts that impair precise histopathological diagnosis.


Assuntos
Artefatos , Lasers , Administração Oral , Biópsia/métodos
10.
Lasers Med Sci ; 39(1): 3, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38082158

RESUMO

Palladium nanoparticles (Pd NPs) show significant promise as agents for the photothermal treatment of tumors due to their high photothermal conversion efficiency and thermal stability. theoretical calculations were conducted to investigate the electric field and solid heat conduction of Pd NPs with various sizes and particle distances, aiming to achieve the maximum photothermal conversion efficiency during laser irradiation. Subsequently, Pd NPs with optimal size and structure were synthesized. In vitro and in vivo experiments were conducted to evaluate photothermal conversion. The theoretical results indicated that a peak temperature of 90.12 °C is achieved when the side length is 30 nm with a distance of 2 nm. In vitro experiments demonstrated that the photothermal conversion efficiency of Pd NPs can reach up to 61.9%. in vivo experiments revealed that injecting Pd NPs into blood vessels can effectively reduce the number of laser pulses by 22.22%, thereby inducing obvious vasoconstriction.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Paládio/farmacologia , Paládio/química , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Análise de Elementos Finitos , Nanopartículas/química , Neoplasias/terapia , Luz , Fototerapia/métodos , Linhagem Celular Tumoral
11.
Nano Lett ; 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36190454

RESUMO

Plasmon-mediated chemical reactions have attracted intensive research interest as a means of achieving desirable reaction yields and selectivity. The energetic charge carriers and elevated local temperature induced by the nonradiative decay of surface plasmons are thought to be responsible for improving reaction outcomes. This study reports that the plasmoelectric potential is another key contributor in plasmon-mediated electrochemistry. Additionally, we disclose a convenient and reliable method for quantifying the specific contributions of the plasmoelectric potential, hot electrons, and photothermal heating to the electroreduction of oxygen at the plasmonic Ag electrode, revealing that the plasmoelectric potential is the dominating nonthermal factor under short-wavelength illumination and moderate electrode bias. This work elucidates novel mechanistic understandings of plasmon-mediated electrochemistry, facilitating high-performance plasmonic electrocatalyst design optimization.

12.
Int J Mol Sci ; 24(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37047212

RESUMO

Electromagnetic waves are widely used in both military and civilian fields, which could cause long-term and high-power exposure to certain populations and may pose a health hazard. The aim of this study was to simulate the long-term and high-power working environment of workers using special electromagnetic radiation occupations to clarify the radiation-induced stress response and cardiac damage and thus gain insights into the mechanisms of injuries caused by electromagnetic radiation. In this study, the combination of microwave and stress was an innovative point, aiming to broaden the research direction with regard to the effect and mechanism of cardiac injury caused by radiation. The myocardial structure was observed by optical and transmission electron microscope, mitochondrial function was detected by flow cytometry, oxidative-stress markers were detected by microplate reader, serum stress hormone was detected by radioimmunoassay, and heart rate variability (HRV) was analyzed by multichannel-physiological recorder. The rats were weighed and subjected to an open field experiment. Western blot (WB) and immunofluorescence (IF) were used to detect the expressions and distributions of JNK (c-Jun N-terminal kinase), p-JNK (phosphorylated c-Jun N-terminal kinase), HSF1 (heat shock factor), and NFATc4 (nuclear factor of activated T-cell 4). This study found that radiation could lead to the disorganization, fragmentation, and dissolution of myocardial fibers, severe mitochondrial cavitation, mitochondrial dysfunction, oxidative-stress injury in myocardium, increase to stress hormone in serum, significant changes in HRV, and a slow gain in weight. The open field experiment indicated that the rats experienced anxiety and depression and had decreased exercise capacity after radiation. The expressions of JNK, p-JNK, HSF1, and NFATc4 in myocardial tissue were all increased. The above results suggested that 30 mW/cm2 of S-band microwave radiation for 35 min could cause both physiological and psychological stress damage in rats; the damage was related to the activation of the JNK pathway, which provided new ideas for research on protection from radiation.


Assuntos
Traumatismos Cardíacos , Micro-Ondas , Ratos , Animais , Micro-Ondas/efeitos adversos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Fatores de Transcrição/metabolismo , Hormônios/metabolismo , Apoptose
13.
Chemphyschem ; 23(1): e202100670, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34643984

RESUMO

Laser induced thermal effect is inevitable in upconversion particle assisted near-infrared polymerization (UCAP). Herein, the influence of thermal effects on the polymerization behavior are investigated. The effects of up-conversion particles content and NIR laser intensity on the polymerization rate and surface oxygen inhibition were systematically investigated, and the temperature evolution and complex viscosity changes in the polymerization system during the polymerization process were also monitored. In addition, polymerization experiments conducted on a controlled temperature platform were used to study the effect of NIR heating on the polymerization behavior. The results show that the near-infrared thermal effect promotes the polymerization reaction, but also causes severe oxygen inhibition which has an adverse effect on polymerization. Finally, NIR curing materials with enhanced mechanical properties than those of conventional UV curing materials were obtained.


Assuntos
Lasers , Luz , Polimerização , Temperatura
14.
Virol J ; 19(1): 161, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224556

RESUMO

Pathogenic viral infections have become a serious public health issue worldwide. Viruses can infect all cell-based organisms and cause varying injuries and damage, resulting in diseases or even death. With the prevalence of highly pathogenic viruses, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it is urgent to develop efficient and safe approaches to inactivate pathogenic viruses. Traditional methods of inactivating pathogenic viruses are practical but have several limitations. Electromagnetic waves, with high penetration capacity, physical resonance, and non-contamination, have emerged as a potential strategy to inactivate pathogenic viruses and have attracted increasing attention. This paper reviews the recent literature on the effects of electromagnetic waves on pathogenic viruses and their mechanisms, as well as promising applications of electromagnetic waves to inactivate pathogenic viruses, to provide new ideas and methods for this inactivation.


Assuntos
COVID-19 , Viroses , Radiação Eletromagnética , Humanos , SARS-CoV-2
15.
World J Urol ; 40(7): 1867-1872, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35614278

RESUMO

PURPOSE: There isscarce evidence to date on how temperature develops during holmium laser enucleation of the prostate (HoLEP). We aimed to determine the potential heat generation during HoLEP under ex vivo conditions. METHODS: We developed two experimental setups. Firstly, we simulated HoLEP ex vivo using narrow-neck laboratory bottles mimicking enucleation cavities and a prostate resection trainer. Seven temperature probes were placed at different locations in the experimental setup, and the heat generation was measured separately during laser application. Secondly, we simulated high-frequency current-based coagulation of the vessels using a roller probe. RESULTS: We observed that the larger the enucleated cavity, the higher the temperature rises, regardless of the irrigation flow rate. The highest temperature difference with an irrigation flow was approximately + 4.5 K for a cavity measuring 100ccm and a 300 ml/min irrigation flow rate. The higher flow rate generates faster removal of the generated heat, thus cooling down the artificial cavity. Furthermore, the temperature differences at different irrigation flow rates (except at 0 ml/min) were consistently below 5 K. Within the resection trainer, the temperature increase with and without irrigation flow was approximately 0.5 K and 3.0 K, respectively. The mean depth of necrosis (1084 ± 176 µm) achieved by the roller probe was significantly greater when using 144 W energy. CONCLUSION: Carefully adjusted irrigation and monitoring during HoLEP are crucial when evacuating the thermal energy generated during the procedure. We believe this study of ours provides evidence with the potential to facilitate clinical studies on patient safety.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Hólmio , Humanos , Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Masculino , Próstata/cirurgia , Hiperplasia Prostática/cirurgia , Temperatura , Ressecção Transuretral da Próstata/métodos , Resultado do Tratamento
16.
World J Urol ; 40(1): 161-167, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34476596

RESUMO

PURPOSE: To objectively determine whether there is potential thermal tissue damage during Tm:YAG laser-based LUTS treatment. METHODS: Our experimental model was comprised of a prostatic resection trainer placed in a 37 °C water bath. In a hollowed-out central area simulating the urethral lumen, we placed a RigiFib 800 fibre, irrigation inflow regulated with a digital pump, and a type K thermocouple. A second thermocouple was inserted 0.5/1 cm adjacently and protected with an aluminum barrier to prevent it from urethral fluid. We investigated continuous and intermittent 120 W and 80 W laser application with various irrigation rates in eight measurement sessions lasting up to 14 min. Thermal measurements were recorded continuously and in real-time using MatLab. All experiments were repeated five times to balance out variations. RESULTS: Continuous laser application at 120 W and 125 ml/min caused a urethral ∆T of ~ 15 K and a parenchymal temperature increase of up to 7 K. With 50 ml/min irrigation, a urethral and parenchymal ∆T of 30 K and 15 K were reached, respectively. Subsequently and in absence of laser application, prostatic parenchyma needed over 16 min to reach baseline body temperature. At 80 W lower temperature increases were reached compared to similar irrigation but higher power. CONCLUSIONS: We showed that potentially harming temperatures can be reached, especially during high laser power and low irrigation. The heat generation can also be conveyed to the prostate parenchyma and deeper structures, potentially affecting the neurovascular bundles. Further clinical studies with intracorporal temperature measurement are necessary to further investigate this potentially harming surgical adverse effect.


Assuntos
Temperatura Alta/efeitos adversos , Lasers de Estado Sólido/efeitos adversos , Próstata , Prostatectomia/métodos , Humanos , Masculino , Modelos Teóricos
17.
Ecotoxicol Environ Saf ; 230: 113125, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34971997

RESUMO

OBJECTIVES: This study evaluated the associated biological effects of radio-frequency (RF) exposure at 16 T magnetic resonance imaging (MRI) on mice health. MATERIAL AND METHODS: A total of 48 healthy 8-week-old male C57BL/6 mice were investigated. A 16 T high static magnetic field (HiSMF) was generated by a superconducting magnet, and a radiofrequency (RF) electromagnetic field for hydrogen resonance at 16 T (700 MHz) was transmitted via a homemade RF system. The mice were exposed inside the 16 T HiSMF with the 700 MHz RF field for 60 min, and the body weight, organ coefficients, histomorphology of major organs, and blood indices were analyzed for the basal state of the mice on day 0 and day 14. The Heat Shock Protein 70 (HSP70), cyclooxygenase 2 (COX2), and interleukin- 6 (IL-6) were used to evaluate the thermal effects on the brain. Locomotor activity, the open field test, tail suspension test, forced swimming test, and grip strength test were used to assess the behavioral characteristics of the mice. RESULTS: The 16 T HiSMF with 700 MHz RF electromagnetic field exposure had no significant effects on body weight, organ coefficients, or histomorphology of major organs in the mice. On day 0, the expressions of HSP70 and COX2 in the brain were increased by 16 T HiSMF with 700 MHz RF electromagnetic field exposure. However, the expression of HSP70, COX2, and IL-6 had no significant difference compared with the sham group on day 14. Compared with the sham groups, the meancorpuscularvolume (MCV) on day 0 and the total protein (TP) on day 14 were increased significantly, whereas the other blood indices did not change significantly. The 16 T HiSMF with 700 MHz RF electromagnetic field exposure caused the mice to briefly circle tightly but had no effect on other behavioral indicators. CONCLUSIONS: In summary, 16 T HiSMF with 700 MHz RF electromagnetic field exposure for 60 min did not have severe effects on mice.

18.
J Therm Biol ; 109: 103320, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36195388

RESUMO

Little is known on the swimming activity and respiration rate of the cyclopoid copepod Cyclops vicinus. Here, the swimming speed and respiration rate of C. vicinus were measured at different temperatures using a high speed (up to 1200 frames per second) camera and a closed-system respirometry, respectively. For cruise and escape swimming, log-linear relationships were found between temperature (range 1-22 °C) and duration, speed, and frequency of locomotor acts, respectively. The respiration rate of immobilized and active individuals showed log-linear relationships with temperature (range of 2-20 °C) and a thermal coefficient Q10 ≈ 2 was found. The maximum respiration rate of swimming females was 7.8 and 6.4 times higher than that of immobilized individuals at 2 and 20 °C, respectively. To better understand how temperature affects the energy efficiency of copepod swimming, the mechanical energy of movement was estimated from sswimming speed and the metabolic energy was estimated from the amount of oxygen consumed during swimming. Linear relationships between swimming speed and mechanical and metabolic energy, respectively, were found at all experimental temperatures. At 20 °C, the maximum mechanical and metabolic energy costs for movement was 15.2 × 10-5 and 37.7 × 10-4 J h-1, respectively. In the range of 2-20 °C, the mechanical energy attributed to swimming represented only a small portion (4.0-8.2%) of the total metabolic energy. Cold-water specialization probably limited the increase of the swimming speed of C. vicinus at high temperatures compared to that of warm-water adapted species.


Assuntos
Copépodes , Natação , Animais , Metabolismo Energético , Feminino , Humanos , Oxigênio , Consumo de Oxigênio , Taxa Respiratória , Temperatura , Água
19.
Electromagn Biol Med ; 41(2): 121-128, 2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35098842

RESUMO

Doppler ultrasonography (DUSG) is widely used for fetal evaluations. This study investigated the effects of new generation Doppler ultrasound application at different frequencies during pregnancy on postnatal renal development. Six pregnant female rats were divided into three groups. No procedure was performed on the first (control) group. In the second group, transabdominal DUSG was performed continuously for 15 min every day from the first day of gestation until birth. In the third group, DUSG was applied for 15 min every two days. Twenty-four male pups were sacrificed after 60 days. Renal tissues were then collected and subjected to biochemical, histopathological, and immunohistochemical evaluation. Malondialdehyde, glutathione, urea, Ca, K, and Cl levels increased in the DUSG groups compared to the control group (p < .05). Histopathologically, tubular damage increased in the DUSG groups compared to the control group (p < .05). Immunohistochemically, an increase was determined in Caspase-3 expression in the DUSG groups compared to the control group (p > .05). The DUSG groups also exhibited an increase in the superficial areas of the proximal and distal tubules, although the difference compared to the control group was not significant (p > .05). Multiple administrations of new generation DUSG to pregnant rats resulted in deleterious effects on the development of postnatal renal tissue. This shows that DUSG should be applied for as short a time as possible and that re-exposure should be avoided.


Assuntos
Rim , Ultrassonografia Doppler , Animais , Feminino , Rim/diagnóstico por imagem , Masculino , Gravidez , Ratos
20.
Angew Chem Int Ed Engl ; 61(36): e202208574, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35841178

RESUMO

It remains a formidable challenge to realize thermo-rulable circularly polarized luminescence (CPL). Herein, we propose a new strategy by covalently "potting" the emitter into a flexible chiral macrocycle as an adaptive chiral [1]rotaxane to address this issue. Different from its included analogue, the potted emitter [DS] showed adaptive conformers with tunable CPL in varied solvents. Significantly, upon controlled self-assembly, [DS] formed a channel-type nanoarchitecture ([DS]A ), which exhibited an extraordinary thermo-rulable CPL between 25-100 °C. Impressively, the glum was large as 0.024 at 25 °C, which was amplified to 0.040 at 90 °C with a decrease of QY (from 92 % to 80 %). By comparison, the assemblies of cage-type [DS]B and the unpotted emitter showed irreversible or unanswered thermal behaviors. The work demonstrated the thermo-rulable and durable CPL for the first time and provided an insightful understanding of thermal effect on high-temperature and switchable CPL materials.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA