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High-voltage transmission electron microscopes (HVTEMs), which can visualize internal structures of micron thick samples, intrinsically have large instrument sizes because of the static voltage isolation. In this Letter, we develop a compact HVTEM, employing a linear accelerator, a subpicosecond beam chopper, and a linear decelerator. 100 kV electrons initially accelerated by a static field are accelerated at radio frequency (rf) up to 500 kV, transmitting through the sample and finally rf decelerated down to 200 kV to be imaged through a 200 kV energy filter. 500 kV imaging, as well as subnanometer resolution at 200 kV, have been demonstrated.
RESUMO
Integration of fluorescence light and transmission electron microscopy into the same device would represent an important advance in correlative microscopy, which traditionally involves two separate microscopes for imaging. To achieve such integration, the primary technical challenge that must be solved regards how to arrange two objective lenses used for light and electron microscopy in such a manner that they can properly focus on a single specimen. To address this issue, both lateral displacement of the specimen between two lenses and specimen rotation have been proposed. Such movement of the specimen allows sequential collection of two kinds of microscopic images of a single target, but prevents simultaneous imaging. This shortcoming has been made up by using a simple optical device, a reflection mirror. Here, we present an approach toward the versatile integration of fluorescence and electron microscopy for simultaneous imaging. The potential of simultaneous hybrid microscopy was demonstrated by fluorescence and electron sequential imaging of a fluorescent protein expressed in cells and cathodoluminescence imaging of fluorescent beads.
Assuntos
Microscopia Crioeletrônica/instrumentação , Microscopia Crioeletrônica/métodos , Microscopia Eletrônica de Transmissão/métodos , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Animais , Células Cultivadas , Elétrons , Fluorescência , Fótons , PotoroidaeRESUMO
College students in Japan are restricted from accessing the campus associated with promoting online classes during the COVID-19 pandemic; it would lead to less physical activity and poor relationships with others. Here, we measured 887 college students' amounts of physical activity, sitting time, self-reported cognitive and affective empathy, and perceived social support before and after easing campus entrance restrictions. The amounts of total activity, vigorous-intensity, and moderate-intensity activity in college students, both male and female, increased after easing restrictions of accessing the campus compared during restrictions. The amounts of walking activity were unchanged. Self-reported cognitive empathy scores significantly increased in female students after mitigating restrictions, but not in males. Furthermore, the total of physical activity's change amounts was positively correlated with changes in the scores of affective empathy and perceived family support. In addition, changes in the scores of affective empathy were positively correlated with perceived social help from family, friends, and close people. The current findings imply that increasing physical activity levels after easing restriction of access to the campus would lead to a better quality of life in young adults during the COVID-19 pandemic.
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COVID-19 , Empatia , Exercício Físico , Feminino , Humanos , Masculino , Pandemias , Qualidade de Vida , Apoio Social , Estudantes/psicologia , Universidades , Adulto JovemRESUMO
OBJECTIVES: The health benefits of resistance training for women have been well documented. However, few investigations have been reported on the immune responses to resistance training among young people. To determine the effects of resistance training on natural killer cell activity (NKCA) in young people, a study was conducted among healthy female university students. METHODS: The study was conducted with 22 healthy non athlete female university students (aged 19.8+/-1.3 years) who volunteered to participate in the study. Six women were assigned to exercise group (a) that carried out resistance training five or six times a week, another six women were assigned to exercise group (b) that carried out resistance training three or four times a week, and the remaining ten comprised, the control group (non exercise group). The exercise groups carried out resistance training for both the upper and lower parts of the body using ankle and wrist weights for 8 weeks. Blood samples were obtained at the onset of the study (before the start of any activity in the exercise groups) and at the conclusion of the training (8 weeks later) in order to determine NKCA. A physical fitness test and a muscle strength test were conducted on the subjects to assess the strength of the upper and lower parts of the body, muscular endurance, and flexibility. RESULTS: The mean NKCA at the conclusion of the training showed a significant increase in exercise group (b), even though there was no significant difference in NKCA in the non exercise group or in exercise group (a) between before and after the training. An improvement in physical fitness and muscle strength was observed in exercise group (a) and exercise group (b). CONCLUSIONS: This study showed that resistance training improved physical fitness, muscle strength, and NKCA in young female subjects. Regarding the effects of exercise frequency on NKCA, this study suggests that exercise carried out three of four times a week might be associated with an increase in NKCA.
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Exercício Físico/fisiologia , Células Matadoras Naturais/imunologia , Força Muscular/fisiologia , Aptidão Física/fisiologia , Adulto , Feminino , Humanos , Estudantes , UniversidadesRESUMO
AMG 531 is a novel thrombopoiesis-stimulating peptibody being investigated for the treatment of chronic immune thrombocytopenic purpura. This double-blind, phase I study evaluated the safety, pharmacodynamics, and pharmacokinetics of AMG 531 in healthy Japanese men. Thirty subjects were randomly assigned 4:1 (AMG 531/placebo) to receive 1 dose of AMG 531 (0.3, 1, or 2 microg/kg) or placebo by subcutaneous injection; subjects were evaluated for 6 weeks. AMG 531 was generally well tolerated, with adverse events similar to placebo. Treatment-related adverse events (headache, "feeling hot," malaise) were reported for 5 of 24 AMG 531-treated subjects. Platelets generated after exposure to AMG 531 functioned normally. Four of 8 subjects receiving 1 microg/kg and 7 of 8 receiving 2 microg/kg had platelet count increases > or =1.5-fold over baseline, an effect similar to that seen in non-Japanese subjects. Serum AMG 531 concentrations were below the lower limit of quantification in all but 2 subjects receiving 2 microg/kg.
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Proteínas de Transporte/farmacocinética , Adulto , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Cefaleia/induzido quimicamente , Humanos , Injeções Subcutâneas , Japão , Masculino , Contagem de Plaquetas , Receptores Fc/administração & dosagem , Proteínas Recombinantes de Fusão , TrombopoetinaRESUMO
OBJECTIVES: To determine the relationship between lifestyle and hemorheology among young people, a study was conducted among healthy university students. Because few investigations have been reported on the relationship between lifestyle factors and hemorheology by gender in young people, we analyzed the effects of lifestyle on hemorheology by administering an assessment questionnaire and by measuring whole blood passage time using MC-FAN (Micro Channel array Flow ANalyzer) and hematological and blood biochemical variables for female and male university students. METHODS: The study was conducted with 40 healthy nonathlete subjects (20 females aged 19.9+/-1.3 years and 20 healthy males aged 20.6+/-1.4 years) who volunteered to participate in the study. The smoking, alcohol drinking, eating, and other habits of the subjects were investigated using a questionnaire. Blood was obtained to determine whole blood passage time and hematological and blood biochemical variables. RESULTS: The mean value of whole blood passage time was significantly shorter in females (43.4+/-5.2 sec/100 microl) than in males (58.2+/-13.6 sec/100 microl). The mean values of RBC, Hb, Ht, MCHC, Alb, TG, Cr, UA, K, Ca, Fe, AST and ALT were significantly lower in females than in males, and the mean value of HDL-C was significantly higher in females than in males. In females, Spearman's correlation coefficient showed a positive correlation between whole blood passage time and RBC, and a negative correlation between whole blood passage time and TG It also showed a positive correlation between whole blood passage time and Plt, and a negative correlation between whole blood passage time and Alb in males. Among the lifestyle factors, the mean value of whole blood passage time in females who consumed salt lightly was significantly longer than that in females who consumed salt moderately. The mean value of whole blood passage time in males who liked sweets was significantly longer than that in males who were neutral to sweets. CONCLUSIONS: The present study showed that whole blood passage time is shorter in females than in males for young people. This conforms to the pattern shown in previous studies which investigated blood passage time among the elderly and people in their prime of life. It is conceivable that females have a higher fluidity than males in all age brackets. Regarding the effects of lifestyle on hemorheology, the present study suggests that several lifestyle factors are related to whole blood passage time and their effects differ according to gender.
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Hemorreologia , Estilo de Vida , Estudantes , Universidades , Adulto , Feminino , Humanos , Masculino , Descanso/fisiologia , Caracteres Sexuais , Inquéritos e QuestionáriosAssuntos
Empatia , Comportamento Sedentário , Exercício Físico , Nível de Saúde , Humanos , Autorrelato , Adulto JovemRESUMO
A fast multi-slice image simulation by parallelized computation using a graphics processing unit (GPU) has been developed.ãThe image simulation contains multiple sets of computing steps, such as Fourier transform and pixel-to-pixel operation. The efficiency of GPU varies depending on the type of calculation. In the effective case of utilizing GPU, the calculation speed is conducted hundreds of times faster than a central processing unit (CPU). The benchmark test of parallelized multi-slice was performed, and the results of contents, such as TEM imaging, STEM imaging and CBD calculation are reported. Some features of the simulation software are also introduced.
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A new fabrication method of carbon based phase plates for phase-contrast transmission electron microscopy is presented. This method utilizes colloidal masks to produce pores as well as disks on thin carbon membranes for phase modulation. Since no serial process is involved, carbon phase plate membranes containing hundreds of pores can be mass-produced on a large scale, which allows "disposal" of contaminated or degraded phase modulating objects after use. Due to the spherical shape of the mask colloid particles, the produced pores are perfectly circular. The pore size and distribution can be easily tuned by the mask colloid size and deposition condition. By using the stencil method, disk type phase plates can also be fabricated on a pore type phase plate. Both pore and disk type phase plates were tested by measuring amorphous samples and confirmed to convert the sinus phase contrast transfer function to the cosine shape.
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We have been developing a combination method for environmental TEM (E-TEM) and phase-plate TEM (P-TEM) that enables direct observations of the structure of biological molecules in aqueous solution. It is clearly demonstrated that the biological molecules in a water layer can be imaged by the combined method without any stain. The spatial resolution obtained in the present study was about 10nm. This should be improved by using energy filtering. The image contrast of the specimen in water was reduced in comparison with that in vacuum. A model calculation that includes the effects of beam broadening, intensity decrease, and background increase caused by scattering from the water layer around the specimen shows that an increase in the thickness of the water layer reduces the contrast, intensity, and resolution of the image.
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Microscopia Eletrônica de Transmissão/métodos , Músculo Esquelético/ultraestrutura , Miosinas/ultraestrutura , Água , Animais , Planejamento Ambiental , Ambiente Controlado , Microscopia de Contraste de Fase/métodos , Coelhos , SoluçõesRESUMO
A Zernike-type phase plate, which consisted of an amorphous carbon film, was developed for a 120 kV transmission electron microscope (TEM). The thickness of the film causes the scattered electrons to experience a pi/2 phase shift. The axial electrons pass through the central hole of the phase plate. The TEM was modified with an additional lens doublet, which allowed more flexibility in applying the phase plates. The doublet transfers the image from the back focal plane to a plane below the objective lens where a special phase plate holder, anticontaminator, and other necessary devices could be employed. The diameter of the central hole in the phase plate was 1 microm. The same mechanical system as in the specimen stage is used to align the axial beam into the hole. The use of a heating holder to protect the phase plate from contamination and consequential charging was investigated. Comparative diffractograms of amorphous carbon are shown with and without using a phase plate, demonstrating the change in phase contrast modulation from a sine to a cosine function when a phase plate is used. Images of biological specimens acquired using a phase plate are presented and the contrast enhancement due to the cosine transfer function is clearly demonstrated.