A pnCCD-based, fast direct single electron imaging camera for TEM and STEM

Three-Dimensional Visualization of Whole Synapses by Stem Tomography

Simulators are being used to teach laparoscopic skills before residents get to the operating room. It is unknown whether the use of three-dimensional (3D) vision will facilitate laparoscopic training. Therefore, our objective was to compare the effectiveness of using 3D imaging over the traditional two-dimensional (2D) imaging to teach laparoscopic simulator skills to novice individuals and assess whether 3D imaging ameliorates laparoscopic performance for surgeons who have already adapted to working within a 2D surgical environment. This prospective study involved 36 surgical residents and students. Inexperienced participants included medical students and first- and second-year surgical residents (n = 25). Experienced participants included third- and fifth-year surgical residents (n = 11). Participants were tested on six laparoscopic skills using 2D or 3D imaging systems and then retested about 3 months later using the opposing imaging system. Evaluation of performance was based on the time elapsed to task completion and the errors committed during that time. The experienced participants performed better than the inexperienced participants regardless of the imaging system. Inexperienced participants initially tested using 2D imaging required significantly more time and/or made more errors to complete five of the six laparoscopic tasks compared to those initially tested using 3D imaging (p < 0.05). After initial testing on 3D imaging, inexperienced participants retested using 2D imaging performed significantly better on five of six tasks compared to the scores of inexperienced participants initially tested on 2D imaging (p < 0.05). In contrast, the inexperienced participants' retested on 3D after initial 2D imaging did not improve on any laparoscopic task compared to the scores of inexperienced participants initially tested on 3D imaging. Among the experienced participants, no significant difference in time or errors to task completion was observed under 2D imaging compared to 3D imaging during the first or second testing session. Our study indicates that 3D imaging offers significant advantages in the teaching of laparoscopic skills to inexperienced individuals.

On the measurement of surface step heights by low-loss imaging in stem

Objective To evaluate the accuracy of surgical navigation for localization and orientation of the femoral stem component in total hip arthroplasty, nethods In the hypothesized space, 3-D images of femoral stem were reconstructed. The coronal, sagittal and horizontal axes and scale divisions were established to calculate the displacement and rotation of the stem. Matching between the stem and its 3-D images was performed while the stem was moved in various distances and angles on the digital motion-platform. Then the actual change in the position of the implant and the caleulative data obtained from the navigation system were compared to evaluate the accuracy. Results The mean difference in displacement between the measurements and the actual changes was (1.01 ±0.47) mm, and the mean difference in the measured and actual angles was 1.09°±0.62°. The duplicate test found no significant difference (t = 0.238, P > 0.05). Conclusion Precise placement of the stem in the desired location and orientation can be achieved by the navigation system in the total hip arthroplasty. Key words: Arthroplasty, replacement, hip; Prosthesis fitting; Surgery, computer-assisted

In this chapter three fully integrated optical receivers down to 40 nm CMOS are described. In addition two optical receivers with off-chip photodiode follow. Finally optical sensors are introduced to complete the application spectrum of optoelectronic nanometer CMOS circuits: one two-dimensional (2D) image sensor, two three-dimensional (3D) image sensors and a positron-emission tomography (PET) sensor for medical applications.

According to the statistic data of cancer in China, breast cancer has the highest incidence in female residents in cities of China. Although the traditional therapies, including surgery, radiation therapy, chemotherapy and hormone therapy have led to the increased 5-year and 10-year survival, there are still a small number of cancer cells survived from treatment, causing cancer recurrence and/or metastasis. Around 70% of survived breast cancer can metastasize to the lung, 60% to the bone and liver and 15% to the brain. Breast cancer stem cells, a subpopulation of breast cancer cells carrying stem cell properties, have strong ability to regenerate tumor and natural resistance to radiation and chemotherapy, which may be responsible for cancer recurrence and metastasis. The strategies targeting at cancer stem cell bring new hope for the treatment of cancer in the near future. In human breast cancer tissues, ALDH positive cells and CD44+ CD24- Lin- cells have been identified as breast cancer stem cells. In this review, we discussed the identification, origin, properties, regulatory mechanism of breast cancer stem cells and the resistance against radiation and chemotherapy, as well as the advances of clinical targeted therapy. Key words: Breast neoplasms; Neoplastic stem cells; Radiotherapy; Chemotherapy; Drug resistance

Complex aortic atherosclerotic plaques (AAPs) carry a significant risk of embolism. Currently, two-dimensional (2D) transoesophageal echocardiography (TOE) is the principal diagnostic tool of AAPs. However, we hypothesized that the data obtained from three-dimensional (3D) imaging may improve AAPs' spatial assessment. The study included 67 patients (aged 70 ± 15 years, 35 men), who had routine TEE studies. The thoracic aorta was studied from arch to distal descending aorta, using the x-plane mode (simultaneous short- and long-axis views). If focal intimal thickening (suggestive of AAP) was detected, the 3D zoom algorithm was exercised on the specific site with further post-processing on a Q-lab workstation to measure its thickness in the X, Y, and Z dimensions. The AAP contour was defined qualitatively as regular or irregular in each mode. A total of 100 AAPs were investigated. The AAP thickness estimation was significantly greater in the 3D mode than in the 2D mode (0.51 ± 0.33 vs. 0.28 ± 0.20 cm, P < 0.001). The rate of complex AAPs (defined by AAP thickness of ≥4 mm) was two-fold higher with 3D imaging than with 2D imaging (27% with 2D imaging alone vs. 53% with the addition of 3D imaging). The rate of irregular AAPs increased from 29 to 65% when assessed with 3D imaging compared with 2D imaging. This study has shown a significant difference in the estimation of AAPs between 2D and 3D TEE. The significant shift to a more complex AAPs profile may suggest that 3D imaging is preferable for the assessment of aortic atherosclerosis burden.

Although most research on human facial attractiveness has used front-facing two-dimensional (2D) images, our primary visual experience with faces is in three dimensions. Because face coding in the human visual system is viewpoint-specific, faces may be processed differently from different angles. Thus, results from perceptual studies using front-facing 2D facial images may not be generalizable to other viewpoints. We used rotating three-dimensional (3D) images of women's faces to test whether men's attractiveness ratings of women's faces from 2D and 3D images differed. We found a significant positive correlation between men's judgments of women's facial attractiveness from 2D and 3D images (r = 0.707), suggesting that attractiveness judgments from 2D images are valid and provide similar information about women's attractiveness as do 3D images. We also found that women's faces were rated significantly more attractive in 3D images than in 2D images. Our study verifies a novel method using 3D facial images, which may be important for future research on viewpoint-specific social perception. This method may also be valuable for the accurate measurement and assessment of facial characteristics such as averageness, identity, attractiveness, and emotional expression.

In this chapter, the basic principles of atomic resolution scanning transmission electron microscopy (STEM) will be described. Particular attention will be paid to the benefits of the incoherent Z-contrast imaging technique for structural determination and the benefits of aberration correction for improved spatial resolution and sensitivity in the acquired images. In addition, the effect that the increased beam current in aberration corrected systems has on electron beam-induced structural modifications of inorganic systems will be discussed. Procedures for controlling the electron dose will be described along with image processing methods that enable quantified information to be extracted from STEM images. Several examples of the use of aberration-corrected STEM for the study of nanoscale systems will be presented; a quantification of vacancies in clathrate systems, a quantification of N doping in GaAs, a quantification of the size distribution in nanoparticle catalysts, and an observation of variability in dislocation core composition along a low-angle grain boundary in SrTiO3. The potential for future standardized methods to reproducibly quantify structures determined by STEM and/or high-resolution TEM will also be discussed.

Signal modeling for two-dimensional image structures

Three-dimensional (3D) Image quality assessment (IQA) is becoming one of hot research area recently. 3D image refers to a technique for enhancing the illusion of depth and protrusion in an image by presenting two offset images separately to the left and right eye of the viewer. These two-dimensional images are combined in the brain to give the perception of 3D depth and protrusion. With the advent of visual revolution, 3D visual becoming more and more important to us, but how could we enjoy an excellent effect 3D image or video? This is the question that we would like to solve in this paper, and the answer is an assessment of 3D image system based on objective and subjective method was built and in this paper we discussed the result comprehensively.

To study the cancer stem cell populations in esophageal cancer cell lines KYSE150 and TE1 and identify whether resulting stem-like cell spheres display radiation resistance characteristics. Serum-free medium (SFM) suspension was used to culture the esophageal cancer stem cell lines and enrich the esophageal stem-like cell spheres. RT-PCR assay was used to detect the stem cell gene expression in the sphere cells. Radiosensitivity of the sphere cells and parental cells were evaluated by clone formation assay. Different cells after irradiation at different doses were tested to evaluate the changes of sphere formation, and cell cycle and CD44(+)CD271(+) expression of the sphere cells were also analyzed by flow cytometry before and after irradiation. Cancer stem-like cell spheres were generated from KYSE150 and TE1 cells and enriched by culture in serum-free medium, and the number of spheres was increasing alone with the increase of cell passages. The numbers of spheres formed from the 1st, 2nd and 3rd generations of KYSE150 cells were 25 ± 2, 37 ± 2 and 47 ± 3, respectively. The numbers of spheres formed from the 1st, 2nd and 3rd generations of TE1 cells were 15 ± 3, 24 ± 3 and 36 ± 4, respectively. Certain doses of radiation increased the sphere formation rate. The average survival fraction (SF2) of the suspension-cultured KYSE150 stem-like cell spheres after 2 Gy irradiation were 0.81 ± 0.03 and 0.69 ± 0.04, while that of TE1 parental cells were 0.87 ± 0.01 and 0.80 ± 0.03 (P < 0.05 for all). In the esophageal parental KYSE150 and TE1 cells, arrest at G2 phase was induced after irradiation. After the same dose of irradiation, the inhibition of proliferation of the cancer stem cells was lower than that of the parent cells (P < 0.05). After 0, 4 and 8 Gy irradiation, the CD44(+)CD271(+) cell percentage of KYSE150 parental cells were (1.08 ± 0.03)%, (1.29 ± 0.07)% and (1.11 ± 0.09)%; the CD44(+)CD271(+) cell percentage of TE1 parental cells were (1.16 ± 0.11)%, (0.97 ± 0.08)% and (1.45 ± 0.35)% (P > 0.05 for all). After 0, 4 and 8 Gy irradiation, the percentage of CD44(+)CD271(+) cells of KYSE150 stem cell-like spheres were (35.83 ± 1.23)%, (44.90 ± 1.67)% and (57.77 ± 1.88)%, and that of TE1 stem cell-like spheres were (16.07 ± 0.91)%, (22.67 ± 1.12)% and (33.27 ± 1.07)%. Compared the 4 Gy and 8 Gy irradiated KYSE150 and TE1 stem-like cell spheres with the 0 Gy irradiated spheres, the differences were statistically significant (P < 0.05 for all). The cancer stem cells in KYSE150 and TE1 spheres are more radio-resistant than their parental cells. It may suggest that cancer stem cell populations in the esophageal cancer cells are related to the mechanism of occurrence of radioresistance.

Additional data on the magnetic properties of the rare-earth metal Eu have been obtained from neutron diffraction data utilizing an improved powder sample consisting of metal filings. Previous diffraction data on Eu, obtained from a rolled metal foil sample, indicated that the metal became antiferromagnetic at a Néel temperature of 87°K. Information regarding the magnetic moment could not be obtained from the metal foil since the diffraction peak intensities indicated the sample had a preferred orientation; also, the magnetic structure determination was uncertain. The present data verify the transition to an antiferromagnetic state below 91°K which consists of a helical spin structure with the magnetic moments lying parallel to a cube face and with the screw axis directed perpendicular to the moments or along the [100] direction. This structure is based upon the facts that the diffraction data show a single pair of magnetic satellite reflections equally spaced in reciprocal lattice space about each nuclear reflection and, in particular, the [000±] reflection from the magnetic cell is observed. Information regarding the period of the helical structure was obtained from the separation of the satellite reflections. The separation was observed to change very little with temperature and corresponds to a period of 3.5a at T/TN = 1 and increases to 3.6a at T/TN = 0.05, where a is the lattice spacing. The intense [000±] magnetic reflection occurring at a scattering angle of 4.8° permits a calculation of the ordered magnetic moment in Eu. If one takes the magnetic form factor equal to 1 at the above small scattering angle, the experimental saturated ordered moment is 5.9±0.4 μB. Assuming that the magnetic constituent of metallic Eu is a Eu++ ion and is, therefore, characterized by an 8S7/2 state having spin only, the theoretical ordered moment should be gJ = gS = 7 μB. The smaller value of the measured ordered moment as compared to the maximum theoretical value is also characteristic of other rare earth metals. Data on the product of magnetic moment times magnetic form factor (μf) can be obtained from the magnetic satellite diffraction peaks occurring at various scattering angles. These values from Eu are in reasonable agreement with similar values of μf obtained from the compound EuO in earlier work. The intensity of the magnetic diffraction peaks as a function of temperature deviates from the usual Brillouin pattern. Instead, the magnetic intensity variation with temperature is proportional to (TN−T)½ over a considerable region below the Néel temperature; this same temperature dependence was also observed in the rolled foil sample. Data taken on the intensity of the nuclear peaks at four different sample temperatures above the Néel temperature over the range from 100° to 293°K indicate an apparent Debye temperature variation from about 70° to 122°K, respectively. We expect to publish the above results giving more details in another journal in the near future.

Single-particle reconstruction can be used to perform three-dimensional (3D) imaging of homogeneous populations of nano-sized objects, in particular viruses and proteins. Here, it is demonstrated that it can also be used to obtain 3D reconstructions of heterogeneous populations of inorganic nanoparticles. An automated acquisition scheme in a scanning transmission electron microscope is used to collect images of thousands of nanoparticles. Particle images are subsequently semi-automatically clustered in terms of their properties and separate 3D reconstructions are performed from selected particle image clusters. The result is a 3D dataset that is representative of the full population. The study demonstrates a methodology that allows 3D imaging and analysis of inorganic nanoparticles in a fully automated manner that is truly representative of large particle populations.

We assessed whether an inexpensive, three-dimensional (3D) ultrasound (US) imaging system could produce clinically useful 3D images, without causing patient discomfort. Five patients were examined. The 3D US system consisted of a transducer holder containing a mechanical motor, and a microcomputer. During data acquisition the transducer was mechanically rotated for 22 seconds, while 200 two-dimensional (2D) US images were collected and formed into a 3D image by the computer. The 3D image was viewed on the computer monitor. The 3D images correlated with the clinical and radiological findings. The new perspectives were helpful in diagnosing eye abnormalities and no patient discomfort occurred. The device was easy to use. It is concluded that, as good-quality 3D and 2D US images were produced quickly, with no patient discomfort, and the device is inexpensive, uncomplicated, and easily attached to existing ultrasound machines, it will probably be useful in clinical practice.