ライフサイエンスコーパス: phase contrast

1 complementary information in attenuation and phase contrast.

2 ill be measured accurately, obtaining strong phase contrast.

3 ith BF at rest and validated using real-time phase-contrast.

4 nally introduced with visible light, Zernike phase contrast(1) is a well-established technique in ful

5 It is intrinsically trimodal, delivering phase contrast, absorption contrast, and scattering ("da

6 ing a time-resolved three-dimensional radial phase-contrast acquisition.

7 The 4D phase-contrast acquisitions were performed, on average,

8 ortic velocity curves created on three axial phase-contrast acquisitions.

9 rtual noncontrast (VNC) images from a single-phase contrast agent-enhanced examination, potentially r

10 ) with routine nonenhanced and portal venous phase contrast agent-enhanced liver CT imaging with thic

11 ct volumetric cardiac and respiratory motion phases, contrast-agent dynamics, and blood flow velocity

12 classical physicochemical characterization, phase contrast and confocal laser scaning microscopy, an

13 elated with optical microscopy (differential phase contrast and confocal microscopy of mutant strains

14 Here, we use phase contrast and fluorescence microscopy to observe gi

15 imuli were confirmed with alamar blue assay, phase contrast and fluorescence microscopy.

16 Quantitative values for attenuation and phase contrast and image noise were determined.

17 contributions increase at a higher rate than phase contrast and inelastic scattering.

18 These confounds are now overcome, using phase contrast and time-lapse videography to reveal the

19 This protocol describes a method combining phase-contrast and fluorescence microscopy, Raman spectr

20 Using these substrates, both phase-contrast and NIMS images of phospholipids from a s

21 -beat BF time history derived from real-time phase-contrast and VMHD was highly correlated using a Sp

22 covery platforms, for example, bright-field, phase contrast, and fluorescence microscopies, are unabl

23 we demonstrate that absorption, dark-field, phase contrast, and two orthogonal differential phase co

24 erebral oxygen delivery was calculated using phase contrast angiography and pre-ductal pulse oximetry

25 aphic techniques, such as time of flight and phase contrast, are considered and their advantages and

26 Ultrahigh-field MRI and, especially, phase contrast, are highly sensitive to tissue changes i

27 y, many attempts have been made to image the phase contrast based on a concept of the beam being defl

28 Using near-field spectral phase contrast based on the Amide I resonance of the pro

29 This technique is successfully applied to phase contrast, bright field, fluorescence microscopy an

30 ude-based contrast mechanisms), we show that phase contrast can actually disappear with extreme tissu

31 or in oximetry-derived flow parameters using phase-contrast cardiac MRI (CMR) as a reference.

32 vious studies demonstrated the usefulness of phase-contrast cardiovascular magnetic resonance (PC-CMR

33 Each participant underwent phase-contrast cardiovascular magnetic resonance measure

34 the first time, time-lapse synchrotron X-ray phase contrast computed tomography (CT) has been used to

35 rt a method for three-dimensional (3D) X-ray phase contrast computed tomography (CT) which gives quan

36 and small intestine) were imaged with x-ray phase contrast computed tomography (PC-CT).

37 Synchrotron radiation phase-contrast computed nanotomography (nano-CT) and two

38 Grating-based phase-contrast computed tomography (PCCT) is a promising

39 We used cryo-electron tomography and Zernike phase contrast cryo-electron tomography to visualize pop

40 Grating-based phase-contrast CT allows differentiation of simulated si

41 results of this study indicate that ex vivo phase-contrast CT can help identify and quantify atheros

42 nd sensitivity, specificity, and accuracy of phase-contrast CT for plaque detection and the potential

43 Applying these criteria, phase-contrast CT had a good sensitivity for the detecti

44 Although not yet applicable in vivo, phase-contrast CT may become a valuable tool to monitor

45 s scanned with an experimental grating-based phase-contrast CT setup consisting of a Talbot-Lau inter

46 Finally, phase-contrast CT uses x-ray refraction properties to im

47 resolution (UHR) CT, photon-counting CT, and phase-contrast CT.

48 ng injury, using high-resolution synchrotron phase-contrast CT.

49 Under these conditions, we show that the phase contrast derives primarily from a unique energy fl

50 ans prefer intrinsic contrast in the form of phase-contrast, differential-interference contrast, or H

51 thin-film samples by combining differential phase contrast (DPC) magnetic imaging with in situ heati

52 its host cell, Synechococcus, using Zernike phase contrast electron cryo-tomography (cryoET).

53 have used the emerging technique of Zernike phase-contrast electron cryomicroscopy to enhance the im

54 LSN scores from portal venous phase contrast-enhanced thick-section CT images had sign

55 Using synchrotron X-ray phase contrast-enhanced tomography we show exemplar data

56 e compared during the pancreatic parenchymal phase: contrast enhancement for the aorta, the pancreas,

57 4D flow was in better agreement with 2D cine phase-contrast flow (95% limits of agreement: -8.8 and 9

58 of growth and parasite-host interactions by phase contrast, fluorescence in situ hybridization, and

59 Phase contrast, fluorescence, and atomic force microscop

60 However, absorption often is negligible and phase contrast has not been easily available.

61 n provide comparable contributions to tissue phase contrast; however, the sign of iron and lipid cont

62 s obtained include (1) the brightness of the phase contrast image of an individual dormant spore is p

63 90% detection efficiency for brightfield and phase contrast images and provides a new open-source pla

64 , the training data sets of the differential phase contrast images at a pair of sample positions, one

65 se contrast, and two orthogonal differential phase contrast images can simultaneously be generated by

66 terative algorithms to recover amplitude and phase contrast images from diffraction intensity data.

67 chmark our software capability in processing phase contrast images from other laboratories against ot

68 ween the sharpness and spatial resolution in phase contrast images of this eutectic alloy obtained vi

69 ndividual bacterial and mammalian cells from phase contrast images without the need for a fluorescent

70 ne capable of reliable detection of cells in phase contrast images.

71 pairwise comparison of the attenuation- and phase-contrast images and both images simultaneously.

72 Contrary to the common assumption, phase-contrast images in liquids using soft microcantile

73 Using this source, high quality phase-contrast images of biological specimens with a 5-m

74 we precisely quantify these properties using phase-contrast images of hESC colonies of different size

75 Three-dimensional phase-contrast images of the live mouse retina were crea

76 Cartesian two-dimensional (2D) cine phase-contrast images were also acquired in the portal v

77 Standard attenuation- and phase-contrast images were reconstructed from the raw pr

78 cal tweezers; (iii) simultaneously measuring phase-contrast images, Raman spectra and fluorescence im

79 age 29 virions in buffer solutions using the phase-contrast images.

80 ed by a specimen, the so-called differential phase contrast imaging (DPC).

81 ities of synchrotron Propagation-based X-Ray Phase Contrast Imaging (PB-X-PCI) to study a wide range

82 X-ray phase contrast imaging (XPCI) is an innovative imaging t

83 X-ray phase contrast imaging (XPCI) is more sensitive to densi

84 Concomitant phase contrast imaging allowed us to extract a linear de

85 Non-destructive X-ray phase contrast imaging and tomography of heterogeneous m

86 This method relies on the use of phase contrast imaging at high defocus to improve inform

87 es of this eutectic alloy obtained via X-ray phase contrast imaging at the Swiss Light Source (SLS) s

88 X-ray phase contrast imaging has overcome the limitations of X

89 X-ray phase contrast imaging offers a way to visualize the int

90 With tunicamycin or mutant SFTPC expression, phase contrast imaging revealed a change to a fibroblast

91 Grating-based differential phase contrast imaging techniques are compatible with co

92 Here we use synchrotron X-ray phase contrast imaging to study cold hardiness-related c

93 ficient for phase recovery than conventional phase contrast imaging.

94 ed quantitatively whilst in flow using x-ray phase contrast imaging.

95 in pulmonary artery (PA) was quantified with phase contrast imaging.

96 were also observed by Live-Dead staining and phase contrast imaging.

97 he development of a phase plate for in-focus phase contrast imaging.

98 X-ray phase-contrast imaging (XPCI) can dramatically improve s

99 After histologic processing, phase-contrast imaging and histopathologic data were mat

100 tive measurements of FC, NC, and CAs between phase-contrast imaging and histopathologic findings (R >

101 were used to determine the agreement between phase-contrast imaging and histopathologic findings for

102 Phase-contrast imaging at a range of energies provided h

103 Hard X-ray phase-contrast imaging characterizes the electron densit

104 X-ray phase-contrast imaging has recently led to a revolution

105 VCG-derived BF was performed using real-time phase-contrast imaging in 7 healthy subjects (n=7) durin

106 TEM has not been regarded as optimal for the phase-contrast imaging necessary for efficient imaging o

107 In previous phase-contrast imaging studies with betatron sources, si

108 ical dipole trap created using a generalized phase-contrast imaging technique.

109 In this study, we used synchrotron x-ray phase-contrast imaging to visualize the tracheal system

110 Phase-contrast imaging using X-ray sources with high spa

111 High-temporal-resolution phase-contrast imaging was performed in the main and rig

112 Phase-contrast imaging was performed to quantify the deg

113 Values for phase-contrast imaging were substantially distinguishabl

114 a way for the application of high resolution phase-contrast imaging with stable betatron sources usin

115 n asymmetric mask concept that enables X-ray phase-contrast imaging without requiring any movement in

116 Here, with ultrafast X-ray phase-contrast imaging, we show that the formation of vo

117 the optical pump pulse using magnified x-ray phase-contrast imaging.

118 , and swim at speeds detectable by real-time phase-contrast imaging.

119 wide range of liquids, using ultrafast X-ray phase-contrast imaging.

120 ved in the epidermis of Smed-TTBK-d(RNAi) by phase contrast, immunofluorescence, and transmission ele

121 We study the physical origins of phase contrast in dynamic atomic force microscopy (dAFM)

122 We also show that the phase contrast in multiple sclerosis lesions could be al

123 Moreover, we predict that the sign of phase contrast in multiple sclerosis lesions indicates t

124 Contrary to an expectation that the phase contrast in multiple sclerosis lesions should alwa

125 we demonstrate the implementation of Zernike phase contrast in scanning X-ray microscopy, revealing s

126 ng, we have evaluated the x-ray differential phase contrast in view of the projected electron density

127 hy underwent CMR to measure planimetric AVA, phase-contrast indexed stroke volume, LV mass, and focal

128 accumulation of dark material observed using phase contrast light microscopy (indicative of a change

129 Simultaneous acquisition of phase-contrast light microscopy and fluorescently labele

130 ional hemodynamic effects were quantified by phase contrast magnetic resonance angiography at baselin

131 embolization on blood flow as quantified by phase contrast magnetic resonance imaging and hypothesiz

132 atients underwent SPC flow quantification by phase contrast magnetic resonance imaging, including qua

133 imaged vascular structure, leveraging modern phase contrast magnetic resonance imaging, the virtual w

134 idate the capability of navigator-echo-gated phase-contrast magnetic resonance (MR) imaging for measu

135 Aortic arch PWV was measured with phase-contrast magnetic resonance (MR) imaging in a popu

136 thoracoabdominal, and neck vessels by using phase-contrast magnetic resonance (MR) imaging in childr

137 idate caval subtraction two-dimensional (2D) phase-contrast magnetic resonance (MR) imaging measureme

138 ients and control subjects who had undergone phase-contrast magnetic resonance (MR) imaging were incl

139 Quantitative flow was measured by phase-contrast magnetic resonance angiography of the cer

140 has expended due to numerous applications of phase-contrast magnetic resonance imaging (PC-MRI) in CS

141 Cine phase-contrast magnetic resonance imaging can be used to

142 Cine phase-contrast magnetic resonance imaging examinations w

143 easured cerebral blood flow by 2-dimensional phase-contrast magnetic resonance imaging in participant

144 Cine phase-contrast magnetic resonance imaging may be a valua

145 Cine phase-contrast magnetic resonance imaging measurement of

146 atio to assess kidney function and performed phase-contrast magnetic resonance imaging of basilar and

147 patients with acute kidney injury using cine phase-contrast magnetic resonance imaging.

148 ham-operated rats, were examined by cine and phase-contrast magnetic resonance imaging.

149 d calibrated versus aortic BF measured using phase-contrast magnetic resonance in 10 subjects (n=10)

150 Baseline arterial phase contrast material-enhanced (CE) MR imaging was use

151 Purpose To determine whether single-phase contrast material-enhanced dual-energy material at

152 oracic junction is achieved with a quadruple-phase contrast media injection protocol.

153 Phase-contrast micro-CT achieved cellular resolution of

154 nerated by either CLT or DMM, we showed that phase-contrast micro-CT distinguished control and OA car

155 sion This work demonstrated the use of x-ray phase-contrast micro-CT for detailed volumetric anatomic

156 ord and column by comparing quality of x-ray phase-contrast micro-CT images of nondissected Thiel-emb

157 nd then employ monochromatic and propagation phase-contrast micro-CT imaging to enable the imaging of

158 The x-ray phase-contrast micro-CT of formalin-fixed boneless cords

159 Results The x-ray phase-contrast micro-CT of Thiel-embalmed samples result

160 o evaluate the viability of postmortem x-ray phase-contrast micro-CT to provide tissue-conserving, hi

161 Propagation-based x-ray phase-contrast micro-CT was used with monochromatic 60-k

162 ould also be observed in images generated by phase-contrast micro-CT.

163 Phase contrast microCT of chemically fixed yet unstained

164 phology of isolated MLECs were observed with phase contrast microscope.

165 sent a new approach for retrieving halo-free phase contrast microscopy (hfPC) images by upgrading the

166 ic acid and Ca(2+) (CaDPA) were monitored by phase contrast microscopy and Raman spectroscopy, respec

167 Phase contrast microscopy assesses changes in refractili

168 Fluorescence and phase contrast microscopy revealed characteristic apopto

169 ology that combines fluorescence microscopy, phase contrast microscopy, and laser tweezers Raman spec

170 opy with simultaneous patch-clamp recording, phase contrast microscopy, and traction force microscopy

171 wth factor-beta1 (TGF-beta1) was analyzed by phase contrast microscopy, immunofluorescence, quantitat

172 d of the rapid drop in spore refractility by phase contrast microscopy, precisely corresponds to the

173 present a methodology that combines external phase contrast microscopy, Raman spectroscopy, and optic

174 ation and vegetative outgrowth by time lapse phase contrast microscopy, transmission electron microsc

175 ifferential interference contrast (DIC), and phase contrast microscopy, we tracked the movement of MT

176 imaging techniques such as fluorescence and phase contrast microscopy.

177 terns were linked in real-time to high power phase contrast microscopy.

178 erior vitreous detachment were examined with phase-contrast microscopy and confocal microscopy after

179 e periods on the order of weeks by utilizing phase-contrast microscopy and show that these cells acqu

180 ellar motion, visualizing the cell bodies by phase-contrast microscopy and the flagellar filaments by

181 Phase-contrast microscopy and Wright staining showed mor

182 rulent NAP1 strain using optical density and phase-contrast microscopy assays.

183 Phase-contrast microscopy consistently identified a crea

184 specimens were processed as flat mounts for phase-contrast microscopy followed by immunolabeling for

185 at combines the automated image analysis for phase-contrast microscopy movies with an easy-to-use int

186 pted to use multi-trap Raman spectroscopy or phase-contrast microscopy of spores adhered on a cover s

187 nveloping membranous structure identified on phase-contrast microscopy to show positive stain results

188 The experiments were videorecorded (phase-contrast microscopy), and PMN adhesion/migration w

189 pseudoholes (14 eyes) using interference and phase-contrast microscopy, immunocytochemistry, and tran

190 py and the motion of the underlying cells by phase-contrast microscopy.

191 NK cells and FLS were studied by time-lapse phase-contrast microscopy.

192 ten requires the use of transmitted light or phase-contrast microscopy.

193 ect diatoms on two-channel (fluorescence and phase-contrast) microscopy images by predicting bounding

194 Here we present a phase-contrast microtomogram of a biological sample usin

195 ii by means of propagation X-Ray Synchrotron phase contrast microtomography using both holotomography

196 X-ray phase-contrast microtomography (XPCmuT) is a label-free,

197 measured in infants with CHD (n = 49) using phase contrast MR imaging and the relationship between C

198 The phase-contrast MR images obtained in five of the eight p

199 red with caval subtraction and direct inflow phase-contrast MR imaging (mean difference, -1.3 mL/min/

200 ty-encoded MR imaging and that measured with phase-contrast MR imaging (mean ICC, 0.96 +/- 0.03 vs 0.

201 ty-encoded MR imaging and that measured with phase-contrast MR imaging (mean ICC, 0.97 +/- 0.02 vs 0.

202 ificantly larger than that with conventional phase-contrast MR imaging (mean, 0.75 +/- 0.23 vs 0.65 +

203 hose obtained from two separate conventional phase-contrast MR imaging acquisitions, one optimized fo

204 pulmonary artery that is determined by using phase-contrast MR imaging allows accurate estimation of

205 good agreement between PV flow measured with phase-contrast MR imaging and that measured with transit

206 hom went on to undergo ETV, were imaged with phase-contrast MR imaging at 1.5 T to determine rates of

207 Phase-contrast MR imaging can be combined with navigator

208 spective study, healthy volunteers underwent phase-contrast MR imaging in a fasting state and again a

209 al, and neck vessels were estimated by using phase-contrast MR imaging in healthy volunteers to allow

210 Aortic arch PWV measured with phase-contrast MR imaging is a highly significant indepe

211 Conclusion Caval subtraction phase-contrast MR imaging is a simple and clinically via

212 nge, as required for conventional sequential phase-contrast MR imaging measurements.

213 catheterization (RHC) and three-directional phase-contrast MR imaging of the main pulmonary artery.

214 Fifteen Sprague-Dawley rats underwent 2D phase-contrast MR imaging of the portal vein (PV) and in

215 8.3 years +/- 1.4) against directly measured phase-contrast MR imaging PV and proper hepatic arterial

216 Thereafter, consistency of caval subtraction phase-contrast MR imaging-derived TLBF and hepatic arter

217 es in a phantom and to prospectively use the phase-contrast MR sequence to measure three-directional

218 40 late-gestation normal human fetuses using phase-contrast MRI (mean gestational age, 37 [SD=1.1] we

219 ary hypertension by high temporal resolution phase-contrast MRI (PC-MRI) and to correlate the results

220 at the age of 9 years using velocity-encoded phase-contrast MRI and related to maternal oily fish con

221 Strain was measured using high-resolution phase-contrast MRI in 9 adult male rats with myocardial

222 Phase-contrast MRI with metric-optimized gating is a pro

223 Phase-contrast MRI, in combination with measurement of p

224 ploiting technical advances toward real-time phase-contrast MRI, the current work analyzed directions

225 combining X-ray fluorescence tomography and phase contrast nanotomography on the same cell with sub-

226 Phase-contrast OCT enables three-dimensional visualizati

227 of information about a 3D structure from the phase contrast of a single hologram acquired using a con

228 ion micro-computed tomography (micro-CT) and phase-contrast optics followed by quantitative analyses.

229 An electron microscope equipped with Zernike phase-contrast optics produces images with markedly incr

230 etting of optimal illumination necessary for phase contrast or the use of high magnification upright

231 t-tissue visibility with grating-based X-ray phase contrast (PC), we have developed a first preclinic

232 echnique yields attenuation, scattering, and phase-contrast (PC) images from a single exposure.

233 Phase-contrast (PC) MR imaging was performed as the refe

234 In addition to differential phase contrast projection images, the method allows the

235 resulting shear waves are imaged by using a phase-contrast pulse sequence with motion-encoding gradi

236 Utilising multi-MHz phase contrast radiography, extended sequences of the co

237 -phase atomic force microscopy with enhanced phase contrast revealed that the misfolding and folding

238 RI sequence and the conventional single-echo phase-contrast (SEPC) MRI sequence, E, E (m), and E/E (m

239 , the compressed-sensing parallel-imaging 4D phase-contrast sequence can augment conventional cardiac

240 hom a compressed-sensing parallel-imaging 4D phase-contrast sequence was performed as part of routine

241 Phase contrast sequences in the aorta and pulmonary arte

242 ed simulator that can accurately capture the phase-contrast signal from a human-scaled numerical phan

243 ll as a dark-field signal in addition to the phase-contrast signal.

244 ssessment of their distinct attenuation- and phase-contrast signal.

245 he data presented here, each cross-sectional phase-contrast slice resulted from five images of 100 or

246 Two radiologists independently reviewed 4D phase-contrast studies for each of 34 patients (mean age

247 Among 123 valves seen in 34 4D phase-contrast studies, 29 regurgitant valves were ident

248 cope for simultaneous amplitude-contrast and phase-contrast surface plasmon resonance imaging (SPRi).

249 utively imaged at 1.5-minute intervals using phase-contrast synchrotron imaging, at positive end-expi

250 Using propagation phase-contrast synchrotron microtomography (PPC-SRmuCT)

251 We used phase-contrast synchrotron X-ray imaging and transmissio

252 greatly facilitate the translation of X-ray phase contrast techniques into mainstream applications.

253 ed tissue can be enhanced using staining and phase contrast techniques.

254 Phase-contrast techniques, such as differential interfer

255 iews, with over an order-of-magnitude higher phase contrast than current near-field grating interfero

256 independently assessed vessel conspicuity on phase-contrast three-dimensional angiograms.

257 n) enable quantitative automated analysis of phase-contrast time-lapse images of cultured neural stem

258 We have used high-resolution, phase-contrast time-lapse microscopy and developed sophi

259 or; (iii) monitoring the division process by phase-contrast time-lapse microscopy; and (iv) processin

260 The power of phase contrast to resolve subtle changes, such as those

261 We combine phase contrast tomographic microscopy (down to 3.3 mum v

262 gated tissue, we exploited synchrotron X-ray phase contrast tomography (XPCT), providing virtual slic

263 idated against independent measurements from phase contrast tomography and electron backscatter diffr

264 Edge illumination x-ray phase contrast tomography is a recently developed imagin

265 High energy X-ray phase contrast tomography is tremendously beneficial to

266 low electron doses comparable to traditional phase-contrast transmission electron microscopy.

267 As a proof-of-concept, an X-ray phase contrast under bending conditions was constructed

268 R imaging was performed by using a 4D radial phase-contrast vastly undersampled isotropic projection

269 Respiratory-gated phase-contrast vastly undersampled isotropic projection

270 viation]) were imaged with respiratory-gated phase-contrast vastly undersampled isotropic projection

271 CMR RVol(AR) was calculated by phase-contrast velocity mapping at the aortic sinuses an

272 using regurgitant fraction (RF) measured by phase-contrast velocity mapping CMR at a median of 40 da

273 and performs well on live-cell, time-lapse, phase contrast video microscopy of hundreds of cells in

274 Phase-contrast video microscopy demonstrated that in the

275 Phase-contrast video microscopy was used to record the m

276 ays using mouse lung slices and confocal and phase-contrast video microscopy.

277 he unenhanced MR angiographic technique with phase-contrast VIPR allows for accurate noninvasive asse

278 es, and overall image quality scores between phase-contrast VIPR and contrast-enhanced MR angiographi

279 tative assessment included evaluation of the phase-contrast VIPR and contrast-enhanced MR angiographi

280 etween the noninvasive TSPG measurement with phase-contrast VIPR and invasive TSPG measurement for me

281 Phase-contrast VIPR images were successfully acquired in

282 the segmental renal arteries were higher for phase-contrast VIPR than for contrast-enhanced MR angiog

283 Although the noise scores were higher with phase-contrast VIPR than with contrast-enhanced MR angio

284 The imaging duration for phase-contrast VIPR was 10 minutes and provided magnitud

285 The vessel diameters measured with phase-contrast VIPR were slightly greater than those mea

286 Velocities measured with phase-contrast VIPR were used to calculate TSPGs by usin

287 The phase-contrast VIPR-derived TSPG measures were slightly

288 tenosis was too small to determine TSPG with phase-contrast VIPR.

289 ing reports, which were generated without 4D phase-contrast visualization.

290 emonstrates the feasibility of grating-based phase contrast with a rotating gantry for the first time

291 nsit (MCT) measurement that uses synchrotron phase contrast X-ray imaging (PCXI) to non-invasively me

292 By combining phase contrast X-ray imaging with an image reconstructio

293 een demonstrated as a valuable capability of phase contrast x-ray imaging.

294 Here we report a high-resolution, low-dose phase contrast X-ray tomographic method for 3D diagnosis

295 oof-of-concept study, we propose multi-scale phase contrast x-ray tomography as a tool to unravel the

296 logy and histopathology based on multi-scale phase contrast x-ray tomography, and use this to investi

297 sition time by ~74% relative to conventional phase contrast X-ray tomography, while maintaining high

298 we have developed theory for absorption- and phase-contrast X-ray imaging.

299 stem tetrapod Ichthyostega using propagation phase-contrast X-ray synchrotron microtomography.

300 when hRSV viruses were imaged using Zernike phase contrast (ZPC) cryo-electron tomography.