Journal articles: 'Shift of axis'

1

Wen-Jun, Xie, and Wei Bing-Bo. "Resonance Shift of Single-Axis Acoustic Levitation." Chinese Physics Letters 24, no. 1 (January 2007): 135–38. http://dx.doi.org/10.1088/0256-307x/24/1/037.

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Kawasaki, Makoto, Ryuji Nagamine, Weijia Chen, Yuan Ma, Akinori Sakai, and Toru Suguro. "Proximal tibia vara involves the medial shift of the tibial articular surface." Journal of Orthopaedic Surgery 28, no. 1 (January 1, 2020): 230949902090259. http://dx.doi.org/10.1177/2309499020902592.

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Purpose: According to the concept of the constitutional varus, the tibial articular surface (TAS) has varus inclination. On the other hand, it has been reported that proximal tibia vara involved medial shift of the TAS. However, it has not been assessed whether varus inclination of the TAS has a correlation with the medial shift. We investigated whether varus inclination of the TAS has a correlation with the medial shift. If there is a correlation between two parameters, the influence of the medial shift of the TAS on the value of the hip–knee–ankle (HKA) angle and the femorotibial angle should be considered. Methods: A total of 112 patients who underwent total knee arthroplasty had anteroposterior view tibia digital radiograph on which five parameters were analyzed. Varus angle of the TAS, the distance between the mechanical axis and the anatomical axis on the articular surface, and the width of the articular surface were measured. Results: The more the proximal tibia had varus deformity, the more the TAS shift medially would be. Therefore, the mechanical axis does not match the anatomical axis. Because the HKA angle was assessed based on the concept that the mechanical and anatomical axes match on the tibia, this angle may not express the true alignment of the lower extremity in knees with proximal tibia vara. Conclusion: In varus knees, the proximal tibia has a medial shift of the TAS that may influence the value of the HKA angle.

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Andrés, P., M. Martínez-Corral, and J. Ojeda-Castañeda. "Off-axis focal shift for rotationally nonsymmetric screens." Optics Letters 18, no. 16 (August 15, 1993): 1290. http://dx.doi.org/10.1364/ol.18.001290.

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Wachsberg, Ronald H., Donald G. Mitchell, Matthew D. Rifkin, Simon Vinitski, and Talin A. Tasciyan. "Chemical shift artifact along the section-select axis." Journal of Magnetic Resonance Imaging 2, no. 5 (September 1992): 589–91. http://dx.doi.org/10.1002/jmri.1880020518.

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Monroe, Michael H., and Laszlo Littmann. "Repetitive QRS axis shift: what is the cause?" Journal of Electrocardiology 44, no. 4 (July 2011): 415. http://dx.doi.org/10.1016/j.jelectrocard.2010.11.018.

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Koc, S., VO Bozkaya, and AB Yikilgan. "Electrocardiographic QRS axis shift, rotation and COVİD-19." Nigerian Journal of Clinical Practice 25, no. 4 (2022): 415. http://dx.doi.org/10.4103/njcp.njcp_9_21.

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Wang, Feng Hui, Kang Lou, and Yong Jun Wang. "Effect of Residual Stresses on Bending Test in Bilayer of SOFC." Applied Mechanics and Materials 83 (July 2011): 104–8. http://dx.doi.org/10.4028/www.scientific.net/amm.83.104.

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When to test the failure stress of Solid Oxide Fuel Cell system, bending approach is consider as one of the convenient ways. The failure stresses are calculated by the elasticity multi -layered theory, in which the neutral axis is determined by the mechanical properties of materials and the thickness of the layers. When cooling from the sintered temperature, residual stresses arise in the multi-layered system due to the mismatch of the thermal expansion coefficients, in this case, the thermal elastic theory point out that the neutral axis depends on residual stress. In this paper, the effect of residual stress on the shift of neutral axis and consequently the failure stress of SOFCs presented, the finite element method was also employed to calculate the SOFCs before and after reduction. The results show that the residual stresses has a distribution along the thickness of the layers, the neutral axis also shifts with the residual stress and the external bending moment, when to test and value the bending stress, the shift of neutral axis should be considered.

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TAKAYAMA, Yoshiaki, Akira SEKI, Kouji IMATAKA, and Jun FUJII. "Exercise-induced QRS axis shift and its clinical significance." Japanese Heart Journal 27, no. 1 (1986): 17–23. http://dx.doi.org/10.1536/ihj.27.17.

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Abe, Tetsuya, and Sumio Kogoshi. "Helical Heliac Coil Device with Large Coil Axis Shift." IEEJ Transactions on Industry Applications 111, no. 9 (1991): 794–95. http://dx.doi.org/10.1541/ieejias.111.794.

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Zapata-Rodrı́guez, Carlos J., Genaro Saavedra, and Manuel Martı́nez-Corral. "Focal shift in optical waves with off-axis focus." Optics Communications 216, no. 1-3 (February 2003): 11–17. http://dx.doi.org/10.1016/s0030-4018(02)02280-0.

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Shimizu, Kimiya, Akiko Misawa, and Yoko Suzuki. "Toric intraocular lenses: Correcting astigmatism while controlling axis shift." Journal of Cataract & Refractive Surgery 20, no. 5 (September 1994): 523–26. http://dx.doi.org/10.1016/s0886-3350(13)80232-5.

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Cantor, A., N. Hendler, and N. Cristal. "Shift from left to right axis deviation during ischemia." Journal of Electrocardiology 25, no. 3 (July 1992): 237–41. http://dx.doi.org/10.1016/0022-0736(92)90009-o.

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13

Medendorp, W. P., B. J. M. Melis, C. C. A. M. Gielen, and J. A. M. Van Gisbergen. "Off-Centric Rotation Axes in Natural Head Movements: Implications for Vestibular Reafference and Kinematic Redundancy." Journal of Neurophysiology 79, no. 4 (April 1, 1998): 2025–39. http://dx.doi.org/10.1152/jn.1998.79.4.2025.

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Medendorp, W. P., B.J.M. Melis, C.C.A.M. Gielen, and J.A.M. Van Gisbergen. Off-centric rotation axes in natural head movements: implications for vestibular reafference and kinematic redundancy. J. Neurophysiol. 79: 2025–2039, 1998. Until now, most studies concerning active head movements in three dimensions have used the classical rotation vector description. Although this description yields both the orientation of the head rotation axis and the amount of rotation, it is incomplete because it cannot specify the location of this rotation axis in space. The latter is of importance for a proper picture of the vestibular consequences of active head movements and has relevance for the problem of how the brain deals with the inherent kinematic redundancy of the multijoint head-neck system. With this in mind, we have extended the rotation vector description by applying the helical axes approach, which yields both the classical rotation vector as well as the location of the rotation axis in space. Subjects ( n = 7), whose head movements were recorded optically, were instructed to shift gaze naturally to targets in 12 different directions at an eccentricity of 40°. The results demonstrate that the axes for these head movements occupy consistently different spatial locations. For purely horizontal movements, the rotation axis is located near a point midway between the two ear canals. For gaze shifts in other directions, the rotation axes are located below the ear canals along two circles, one for movements with an upward component (up circle), the other (typically larger in size) for movements with a downward component (down circle). Purely vertical movement (up and down) axes were located on the lower pole of the up and down circles, respectively. It was found that both circles, the upper poles of which coincided, became larger in size as movement amplitude increased, which means that the axis location shifts to lower and more eccentric locations with respect to the skull for larger flexion and extension movements. Although this pattern could be recognized in most subjects, there were consistent intersubject differences in the absolute size of the circles, their increase with movement amplitude, and in the relative sizes of the up and down circles. Because multiple vertebrae are involved in head movements, there are theoretically many possibilities to execute a certain head movement. The differences in circle patterns among subjects indicate different strategies in resolving this kinematic redundancy problem, a fact that was not apparent from the classical rotation vector part of our description, which yielded a rather uniform picture. A simple model suggests that the downward shift of the location of the rotation axis requires a modulation in vestibulo-ocular reflex gain of ≤10% to maintain fixation of a near target during vertical head movement. The involvement of the otolith system in this process remains to be determined.

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Shin, Y. J., W. J. Kim, H. Y. Kim, and W. Bahng. "Dislocation Analysis of 4H-/6H-SiC Single Crystals Using Micro-Raman Spectroscopy." Materials Science Forum 740-742 (January 2013): 481–84. http://dx.doi.org/10.4028/www.scientific.net/msf.740-742.481.

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Micro-Raman spectroscopy is an excellent non-destructive analysis method, which compensates for disadvantages of KOH method. Raman shift of A1(LO) and E1(TO) band at threading screw dislocation(TSD) were investigated in n-type on/off-axis 4H- and 6H-SiC single crystal wafers by Micro-Raman scattering at room temperature. The results showed that A1(LO) band were shifted toward higher frequency while the E1(TO) band were shifted toward lower frequency on the on-axis wafers. The shifts are caused by increasing electron concentration and lattice disorder near the dislocation core, respectively. In the off-axis wafers, no shifts were observed possibly due to the measurement geometry which does not contain whole dislocation core.

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Yaw, Alexandra M., Autumn Mclane-Svoboda, Duong Nguyen, Thu Van Quynh Duong, and Hanne Mette Hoffmann. "A Mouse Model of Shiftwork Reveals Sex-Specific Impairments in Circadian Behavior and Reproductive Tissue Timekeeping." Journal of the Endocrine Society 5, Supplement_1 (May 1, 2021): A530—A531. http://dx.doi.org/10.1210/jendso/bvab048.1080.

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Abstract Approximately 21 million Americans are employed in nighttime or rotating shiftwork, which is linked with numerous health risks, including reduced reproductive success. While there is a strong body of clinical evidence associating shift workers with deficits in fertility, very little is known about the mechanisms by which shiftwork produces reproductive dysfunction. One important feature of shiftwork is extensive exposure to light at night. Light is one of the strongest timing cues for the circadian system, where exposure to mistimed light (light at night) can disrupt timekeeping throughout the body, leading to a mistiming of physiological processes and resulting in disease development. Our goal is to determine if a light-based model of rotating shiftwork (shift-light), composed of an alternating 6 hour phase advance or delay every 4 days for 5-10 weeks, disrupts circadian rhythms in the reproductive hypothalamic-pituitary-gonadal (HPG) axis, leading to mis-timed tissue rhythms and reduced fertility. We hypothesize that shift-light disrupts wheel running behavior and underlying cellular circadian rhythms in the HPG axis, resulting in reduced reproductive function. Using the validated circadian Per2:luciferase reporter mice, we assessed wheel-running behavior and Per2:luciferase rhythms in tissue explants from males and females. Behavioral data revealed that both sexes adapt their wheel running to shift-light paradigm; however, females, but not males, displayed a significant deficit in their ability to entrain to phase advances following 4 shifts. This sex-specific disruption was supported by preliminary tissue explant Per2:luciferase rhythms, which suggest that shift-light alters tissue level circadian phase synchrony in female, but not male, HPG axis tissues. Importantly, females exhibited shortened estrous cycling during shift-light, suggesting the altered HPG axis synchrony could be directly impacting reproductive function. We are currently working to extend this work to determine how this desynchrony impacts hormone release, including luteinizing hormone and follicle stimulating hormone. Together, this work provides insight into how shiftwork may influence circadian rhythms in reproductive tissues and suggests that females may have increased vulnerability to reproductive deficits from shiftwork.

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Schmid, Peter, and Harald Rose. "Outline of a variable-axis lens with arbitrary shift of the axis in one direction." Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures 19, no. 6 (2001): 2555. http://dx.doi.org/10.1116/1.1418408.

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CHEN, Wenjin, Zhiwei MA, Haowei ZHANG, Wei ZHANG, and Longwen YAN. "Free-boundary plasma equilibria with toroidal plasma flows." Plasma Science and Technology 24, no. 3 (March 1, 2022): 035101. http://dx.doi.org/10.1088/2058-6272/ac48de.

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Abstract Magnetohydrodynamic equilibrium schemes with toroidal plasma flows and scrape-off layer are developed for the ‘divertor-type’ and ‘limiter-type’ free boundaries in the tokamak cylindrical coordinate. With a toroidal plasma flow, the flux functions are considerably different under the isentropic and isothermal assumptions. The effects of the toroidal flow on the magnetic axis shift are investigated. In a high beta plasma, the magnetic shifts due to the toroidal flow are almost the same for both the isentropic and isothermal cases and are about 0.04a 0 (a 0 is the minor radius) for M 0 = 0.2 (the toroidal Alfvén Mach number on the magnetic axis). In addition, the X-point is slightly shifted upward by 0.0125a 0. But the magnetic axis and the X-point shift due to the toroidal flow may be neglected because M 0 is usually less than 0.05 in a real tokamak. The effects of the toroidal flow on the plasma parameters are also investigated. The high toroidal flow shifts the plasma outward due to the centrifugal effect. Temperature profiles are noticeable different because the plasma temperature is a flux function in the isothermal case.

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Moore, Steven T., Eishi Hirasaki, Theodore Raphan, and Bernard Cohen. "Instantaneous rotation axes during active head movements." Journal of Vestibular Research 15, no. 2 (April 1, 2005): 73–80. http://dx.doi.org/10.3233/ves-2005-15203.

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Rotation axes were calculated during active head movements using a motion analysis system. The mean rotation axis for 1 Hz head pitch when seated was posterior (6 mm) and inferior (21 mm) to the interaural axis, shifting 16 mm downwards when standing. During seated 2 Hz head pitch the rotation axis was close to the interaural axis, shifting downwards 15 mm when standing. This downward shift suggests that cervical vertebrae were recruited during head pitch with the trunk unsupported. The proximity of the pitch axis to the otoliths implies minimal otolith activation during small-amplitude, high-frequency pitch rotations, such as those encountered during locomotion. The mean rotation axis for 1 Hz yaw rotation was located slightly posterior (10 mm) to the interaural axis at the midpoint between the vestibular labyrinths when both seated and standing. In addition, the orientation of the plane of yaw rotation relative to the stereotaxic horizontal plane (pitched 5° nose-down) was essentially fixed in head coordinates, regardless of the pitch orientation of the head, suggesting that yaw movements occur about an axis restricted by the mechanical structure of the atlanto-axial joint. The results demonstrate that the instantaneous rotation axes technique overcomes the inherent instability of the helical-axis representation for small head movements.

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Pan, Liu Zhan, Chao Liang Ding, Zhi Guo Zhao, and Xiao Yuan. "Influence of Polarization on the Spectral Changes of Stochastic Electromagnetic Pulsed Beams." Materials Science Forum 663-665 (November 2010): 113–17. http://dx.doi.org/10.4028/www.scientific.net/msf.663-665.113.

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An analytical expression for the spectrum of stochastic spatially and temporally partially coherent electromagnetic Gaussian Schell-model pulsed (GSMP) beams is derived, and used to study the spectral changes of electromagnetic GSMP beams in free space. The influence of polarization on the on-axis relative spectral shift is emphasized. It is shown that the on-axis relative spectral shift increases with increasing the degree of polarization of source P0 for the case of δxx≠δyy, i.e. the spatial coherence length δxx of x component of the electric field at the source is not equal to that of y component. For δxx=δyy or δxx→∞ and δyy→∞, the on-axis relative spectral shift is independent of P0.

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20

Sagie, Alex, Samuel Sclarovsky, Boris Strasberg, Danny Kert, and Aviv Mager. "Significance of Rightward Axis Shift in Anterior Acute Myocardial Infarction." American Journal of Noninvasive Cardiology 5, no. 4 (1991): 229–34. http://dx.doi.org/10.1159/000470447.

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21

Nicola, S. De. "On-axis focal shift effects in focused truncated Bessel beams." Pure and Applied Optics: Journal of the European Optical Society Part A 5, no. 6 (November 1996): 827–31. http://dx.doi.org/10.1088/0963-9659/5/6/008.

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22

Borden, Jonathan A., Jen-san Tsai, and Anita Mahajan. "Effect of subpixel magnetic resonance imaging shifts on radiosurgical dosimetry for vestibular schwannoma." Journal of Neurosurgery 97 (December 2002): 445–49. http://dx.doi.org/10.3171/jns.2002.97.supplement_5.0445.

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Object. The purpose of this study was to evaluate subpixel magnetic resonance (MR) imaging shifts of intracanalicular vestibular schwannomas (VSs) with respect to the internal auditory canal (IAC) as documented on computerized tomography (CT) scanning and to investigate the source of imaging-related localization errors in radiosurgery as well as the effect of such shifts on the dosimetry for small targets. Methods. A shift of the stereotactic coordinates of intracanalicular VSs between those determined on MR imaging and those on CT scanning represents an error in localization. A shift vector places the tumor within the IAC and measures the CT scan/MR image discrepancy. The shift vectors were measured in a series of 15 largely intracanalicular VSs (all < 1.5 cm3 in volume). Using dose volume histogram measurements, the overlap between shifted and unshifted tumors and radiosurgical treatment plans were measured. Using plastic and bone phantoms and thermoluminescent dosimetry measurements, the correspondence between CT and MR imaging targets and treatments delivered using the Leksell gamma knife were measured. Combining these measurements, the correspondence between intended and actual treatments was measured. Conclusions. The delivery of radiation to CT-imaged targets was accurate to the limits of measurement (∼ 0.1 mm). The MR imaging shifts seen in the y axis averaged 0.9 mm and in the z axis 0.8 mm. The corresponding percentage of tumor coverage with respect to apparent target shift decreased from 98 to 77%. This represents a significant potential error when targets are defined solely by MR imaging.

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Bendefy, András, and Péter Horák. "Cylindrical Gears with Changing Ratio." Periodica Polytechnica Mechanical Engineering 61, no. 2 (March 2, 2017): 130. http://dx.doi.org/10.3311/ppme.9870.

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Changing ratio gears are noncircular. It means that if they are combined with a conventional cylindrical gear a changing axis distance will be given. Changing axis distance can generate a lot of difficulties and additional costs in the construction. Our goal was to create changing ratio gears that have cylindrical geometry and interlock with conventional cylindrical gears at a constant axis distance. This can be achieved by applying continuously changing profile shift. Profile shift modifies the diameter of the gears, however it does not have any effect on the ratio; regardless if that is constant or changing. The point of our calculation is that some gears with noncircular rolling curves can have circular pitch curve with the help of changing profile shift.

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Weingarten, H. P., A. Duong, and D. Elston. "Interpretation of sham feeding data: curve-shift studies." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 271, no. 4 (October 1, 1996): R1009—R1016. http://dx.doi.org/10.1152/ajpregu.1996.271.4.r1009.

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We explored the possibility that quantitative analysis of the relationship between sucrose concentration and sham intake differentiated how various treatments affected the intake of sweet solutions. Rats were sham fed sucrose solutions varying in concentration from 0.03125 to 1.5 M. Under different treatment conditions, intake concentration functions were generated that plotted amount sham fed against sucrose concentration. Sucrose concentration that yielded 50% maximal sham intake were calculated to indicate the position of the concentration-intake function on the x-axis. Quinine adulteration of sucrose solutions and injection of 0.5 mg/kg i.p. of the dopamine antagonist pimozide reduced sham intake and shifted the concentration-intake function to the right. Lithium chloride (60 mg/kg i.p.) injected 30 min before sham feeding, a reduction of food deprivation from 18 to 6 h before sham feeding, and 6 micrograms/kg cholecystokinin octapeptide reduced sham intake equivalent amounts but did not shift the concentration-intake functions along the x-axis. The data indicate that of several factors that reduce sham feeding, only some also shift the position of concentration-intake curves, and these curve shifts may identify intake changes mediated by alterations in the processing of the taste input.

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Wang, Zhiguo, Yi Zhang, Xiang Zhan, Qiyuan Jiang, and Hui Luo. "Cross-Axis Coupling Effects in Single-Axis Nuclear Magnetic Resonance Gyroscopes." Sensors 20, no. 3 (January 29, 2020): 734. http://dx.doi.org/10.3390/s20030734.

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Nuclear magnetic resonance gyroscopes (NMRGs) may be operated in an environment with violent vibration that usually contains both linear components and angular components. To analyze the influence of angular vibration on an NMRG, cross-axis coupling effects are studied. The cross-axis rotation rates induce an equivalent magnetic field. Its influence can be described by the Bloch equations. The approximate frequency shift and amplitude of the spin oscillator with an equivalent magnetic field in the cross-axis were obtained, which was validated by numerical simulation. The findings show that the angular vibration component leads to a remarkable error for the NMRG. When the angular vibration frequency is near the Larmor frequency, the oscillation frequency of the spins may be locked to the angular vibration frequency, destroying the NMRG’s ability to measure rotation rates. The cross-axis coupling problem should be considered in the design of an NMRG and corresponding inertial navigation systems.

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Yaw, Alexandra, Autumn McLane-Svoboda, and Hanne Hoffmann. "Shiftwork and Light at Night Negatively Impact Molecular and Endocrine Timekeeping in the Female Reproductive Axis in Humans and Rodents." International Journal of Molecular Sciences 22, no. 1 (December 30, 2020): 324. http://dx.doi.org/10.3390/ijms22010324.

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Shiftwork, including work that takes place at night (nightshift) and/or rotates between day and nightshifts, plays an important role in our society, but is associated with decreased health, including reproductive dysfunction. One key factor in shiftwork, exposure to light at night, has been identified as a likely contributor to the underlying health risks associated with shiftwork. Light at night disrupts the behavioral and molecular circadian timekeeping system, which is important for coordinated timing of physiological processes, causing mistimed hormone release and impaired physiological functions. This review focuses on the impact of shiftwork on reproductive function and pregnancy in women and laboratory rodents and potential underlying molecular mechanisms. We summarize the negative impact of shiftwork on female fertility and compare these findings to studies in rodent models of light shifts. Light-shift rodent models recapitulate several aspects of reproductive dysfunction found in shift workers, and their comparison with human studies can enable a deeper understanding of physiological and hormonal responses to light shifts and the underlying molecular mechanisms that may lead to reproductive disruption in human shift workers. The contributions of human and rodent studies are essential to identify the origins of impaired fertility in women employed in shiftwork.

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Shan, Ming-Guang, Xiang-Yu Liu, Cheng Pang, Zhi Zhong, Lei Yu, Bin Liu, and Lei Liu. "Off-axis digital holographic decarrier phase recovery algorithm combined with linear regression." Acta Physica Sinica 71, no. 4 (2022): 044202. http://dx.doi.org/10.7498/aps.71.20211509.

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Benefitting from the high measurement efficiency, off-axis digital holography (DH) has become a most powerful DH technique for fast and high-accuracy measurement. Owing to the carrier frequency, the real image can be isolated easily in the Fourier spectrum of one off-axis hologram, so that the Fourier transform algorithm (FTA) is the most widely used algorithm for off-axis DH to realize the phase retrieval. In the FTA, one of the most important tasks is to figure out the accurate peak position of the real image and then shift the real image to the center of spectrum to remove the carrier. However, owing to the digitalization of the hologram, the peak position of the real spectrum is always not located at an integral pixel position in the practical applications, resulting in carrier residuals, thereby lowering the retrieval quality. Much work on accurately determining the peak position has been conducted to suppress the carrier residuals, such as by using the spectrum centroid method and zero padding. However, those estimation algorithms can achieve only satisfied accuracy in some situations. Then, spatial carrier phase shift (SCPS) is utilized to expand the utilization of space-bandwidth and avoid the spectrum leakage caused by band-pass filtering. The SCPS decomposes one off-axis hologram into several sub-holograms, in which the carrier induces the phase shifts between sub-holograms. Many on-axis phase retrieval algorithms are combined with SCPS to retrieve the phase from one off-axis hologram. However, the retrieved phase is usually composed of the sample phase and the carrier, so the accurate carrier information is also required to remove the carrier and obtain the correct reconstructed phase. In this paper, an accurate phase retrieval with carrier removal from single off-axis hologram by using the linear regression is proposed to achieve the simultaneous phase retrieval and carrier removal. In this method, four phase-shifted sub-holograms are extracted first from one off-axis hologram by SCPS. Since the phase shift between sub-holograms is linearly proportional to the carrier, the linear regression can be combined with least-square method to retrieve the phase and carrier simultaneously. Both the simulation and experimental results show that the proposed method can determine the carrier accurately and obtain correct phase without carrier. We believe that this proposed method can be applied to practical measurement.

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McCarthy, R. J., and M. P. Kowaleski. "Geometric analysis evaluating the effect of tibial plateau leveling osteotomy position on postoperative tibial plateau slope." Veterinary and Comparative Orthopaedics and Traumatology 17, no. 01 (January 2004): 30–34. http://dx.doi.org/10.1055/s-0038-1632797.

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SummaryThe tibial plateau leveling osteotomy procedure is designed to neutralize cranial tibial thrust by precisely reducing tibial plateau slope. Despite accurate intraoperative measurement and proximal tibial plateau segment rotation, postoperative assessment of tibial plateau slope frequently reveals a measured angle differing from the expected postoperative angle of 5.0 degrees. The effect of osteotomy placement on postoperative tibial plateau slope was evaluated by analysing its effect on the points utilized in tibial plateau slope measurement. Four osteotomy placements, encompassing the point dividing the intercondylar tubercles and an osteotomy centred on this point, were evaluated. The effect of centreing the osteotomy distal to the intercondylar tubercles was more closely evaluated. Formulae to determine the distance the intercondylar tubercles move, the angular shift of the tibial long axis after proximal tibial plateau segment rotation, and the relation of the final and intended tibial plateau slope were derived. Osteotomy placement centred on the proximal tibial long axis point results in a lack of movement or angular shift of the tibial long axis, after proximal tibial plateau segment rotation. Other osteotomy placements result in movement of the intercondylar tubercles, tibial long axis shift, and deviation from the expected postoperative tibial plateau slope. Centreing the tibial plateau leveling osteotomy on the proximal tibial long axis point is the mathematically correct position.

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Shawki, G. S. A., and S. A. R. Naga. "On the Mechanics of Grey Cast Iron Under Pure Bending." Journal of Engineering Materials and Technology 108, no. 2 (April 1, 1986): 141–46. http://dx.doi.org/10.1115/1.3225851.

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This paper presents the results of experiments conducted on lamellar graphite grey cast iron of rectangular section subjected to pure bending. Strain measurements confirm the traditional speculation that plane sections remain plane under strain. Owing to the nonlinear relationship between stress and strain, however, the neutral axis of a loaded specimen is shown to shift away from the centroidal axis. This shift is evidently amplified with increased loading. A computer program is herein specially devised for calculating the shift in neutral axis through satisfaction of the conditions of equilibrium together with checking for possible crack initiation at the extension side. While the simple flexural formula holds very nearly true for the compression side, it fails, however, to predict stresses on the extension side, the situation being further aggravated by higher bending moments. The apparent high bending strength of grey cast iron is fully accounted for.

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Kim, Jung-Wook, Sun-Wook Choi, Ki-Han Kim, Sung-Tae Shin, and Tae-Hoon Yoon. "Vertical Alignment Liquid Crystal Device With Reduced Off-Axis Gamma Shift." Journal of Display Technology 9, no. 10 (October 2013): 779–82. http://dx.doi.org/10.1109/jdt.2013.2277891.

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Kasyutich, Vasili L., Philip A. Martin, and Robert J. Holdsworth. "Phase-shift off-axis cavity-enhanced absorption detector of nitrogen dioxide." Measurement Science and Technology 17, no. 4 (March 23, 2006): 923–31. http://dx.doi.org/10.1088/0957-0233/17/4/044.

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Cojocaru, E., V. Draganescu, and N. Herisanu. "Astigmatism together with longitudinal focal shift in off-axis optical systems." Applied Optics 29, no. 28 (October 1, 1990): 4208. http://dx.doi.org/10.1364/ao.29.004208.

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Cui, Zhiqiang, Longsheng Pan, Huifang Song, Xin Xu, Bainan Xu, Xinguang Yu, and Zhipei Ling. "Intraoperative MRI for optimizing electrode placement for deep brain stimulation of the subthalamic nucleus in Parkinson disease." Journal of Neurosurgery 124, no. 1 (January 2016): 62–69. http://dx.doi.org/10.3171/2015.1.jns141534.

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OBJECT The degree of clinical improvement achieved by deep brain stimulation (DBS) is largely dependent on the accuracy of lead placement. This study reports on the evaluation of intraoperative MRI (iMRI) for adjusting deviated electrodes to the accurate anatomical position during DBS surgery and acute intracranial changes. METHODS Two hundred and six DBS electrodes were implanted in the subthalamic nucleus (STN) in 110 patients with Parkinson disease. All patients underwent iMRI after implantation to define the accuracy of lead placement. Fifty-six DBS electrode positions in 35 patients deviated from the center of the STN, according to the result of the initial postplacement iMRI scans. Thus, we adjusted the electrode positions for placement in the center of the STN and verified this by means of second or third iMRI scans. Recording was performed in adjusted parameters in the x-, y-, and z-axes. RESULTS Fifty-six (27%) of 206 DBS electrodes were adjusted as guided by iMRI. Electrode position was adjusted on the basis of iMRI 62 times. The sum of target coordinate adjustment was −0.5 mm in the x-axis, −4 mm in the y-axis, and 15.5 mm in the z-axis; the total of distance adjustment was 74.5 mm in the x-axis, 88 mm in the y-axis, and 42.5 mm in the z-axis. After adjustment with the help of iMRI, all electrodes were located in the center of the STN. Intraoperative MRI revealed 2 intraparenchymal hemorrhages in 2 patients, brain shift in all patients, and leads penetrating the lateral ventricle in 3 patients. CONCLUSIONS The iMRI technique can guide surgeons as they adjust deviated electrodes to improve the accuracy of implanting the electrodes into the correct anatomical position. The iMRI technique can also immediately demonstrate acute changes such as hemorrhage and brain shift during DBS surgery.

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Kusumi, Ryosuke, Fumiko Kimura, and Tsunehisa Kimura. "Single Crystal Solid-State NMR of Magnetically Oriented Powder." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1086. http://dx.doi.org/10.1107/s205327331408913x.

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Solid-state NMR spectroscopy is one of the most widely used methods for investigating crystal structures, along with the X-ray and neutron diffraction methods. Solid-state NMR can provide structural information including isotropic chemical shift, dipolar and quadrupolar couplings, spin diffusion, and chemical shift tensor. Among these, the chemical shift tensor is of particular significance because the electronic environment around a nucleus is directly reflected on the chemical shift tensor. However, full information of the chemical shift tensor, including principal values and axes, is difficult to obtain experimentally because a large single crystal is required for the measurement. On the other hand, we have proposed the use of a magnetically oriented microcrystal array (MOMA) as an alternative to a single crystal.[1,2] A MOMA is a composite in which microcrystals are aligned three-dimensionally, prepared by using a time-dependent magnetic field. We recently demonstrated that the13C chemical shift tensors of L-alanine crystal can be completely determined by application of the standard procedure in the single-crystal rotation method to a MOMA of L-alanine microcrystals,[3] as shown in Figure 1. The L-alanine MOMA produces sharp resonance peaks without resolution enhancement by magic angle spinning (MAS). In addition, we observed that the positions of the13C resonance peaks vary systematically as a function of the angle ψ that is the sample-rotation angle about the axis inclined by the magic angle with respect to the NMR magnetic field. From the ψ-dependence of the chemical shifts,13C chemical shift tensor was completely determined. We confirmed that the combination of MOMA with the single-crystal rotation method can be applied to other nuclei such as31P and15N. These results clearly show that the MOMA method is a powerful tool for obtaining full information of the chemical shift tensor from a microcrystalline powder without MAS.

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Linck, Martin, Hannes Lichte, and Michael Lehmann. "Off-axis electron holography: Materials analysis at atomic resolution." International Journal of Materials Research 97, no. 7 (July 1, 2006): 890–98. http://dx.doi.org/10.1515/ijmr-2006-0144.

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Abstract In high-resolution off-axis electron holography, the correction of coherent aberrations allows the quantitative interpretation of the amplitude and phase of the object wave up to the information limit of the electron microscope. Since the measured object phase is directly related to the projected atomic potential for sufficiently thin samples, off-axis electron holography is expected to allow distinguishing of different elements in the reconstructed phase image (“holographic materials analysis”). This has already been verified with the example of Ga and As. However, simulations of the atomic phase shift reveal that the interpretation of the measured phase shift in terms of atomic species is generally rather complex. The findings suggest that, in some cases, the requirements as to lateral resolution and phase detection limit will be met only by electron microscopes of the next generation.

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Karelin, Oleksandr, and Anna Tarasenko. "On Factorization of Functional Operators with Reflection on the Real Axis." WSEAS TRANSACTIONS ON MATHEMATICS 20 (April 9, 2021): 171–77. http://dx.doi.org/10.37394/23206.2021.20.18.

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Problems of factorization of matrix functions are closely connected with the solution of matrix Riemann boundary value problems and with the solution of vector singular integral equations. In this article, we study functional operators with orientation-reversing shift reflection on the real axes. We introduce the concept of multiplicative representation of functional operators with shift and its partial indices. Based on the classical notion of matrix factorization, the correctness of the definitions is shown. A theorem on the relationship between factorization of functional operators with reflection and factorization of the corresponding matrix functions is proven.

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Stiefvater, Otto L. "The Triply Determined Substitution Structure of 1,3,4-Thiadiazole by DRM Microwave Spectroscopy." Zeitschrift für Naturforschung A 44, no. 1 (January 1, 1989): 29–40. http://dx.doi.org/10.1515/zna-1989-0108.

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Double Resonance Modulation (DRM) microwave spectroscopy has allowed the determination of the complete substitution structure of normal, mono-deuterated and perdeuterated 1,3.4-thiadiazole (N2C2H2S). The shift of the centre of gravity between the normal and the d2-form and the swing of inertia! axes relative to the C2v symmetrical forms in the 2-d1-species have been used to revise the small coordinates of hydrogen and deuterium atoms.Bond lengths (in Å) and bond angles (in degrees), with uncertainties covering all three molecular forms, are found as follows: The results suggest that the shift and the swing of inertial axes between different ‘parent’ forms, which can both be determined from the moments of multiply substituted molecular isotopes, may be used with advantage to refine the position of near-axis atoms.

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Aravindh Kumar, S. M., and E. Rathakrishnan. "Characteristics of a supersonic elliptic jet." Aeronautical Journal 120, no. 1225 (March 2016): 495–519. http://dx.doi.org/10.1017/aer.2016.7.

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ABSTRACTComparative mixing of a Mach 2 elliptical free jet from a convergent-divergent elliptic nozzle with an aspect ratio of 2:1 in the presence of adverse and marginally favourable pressure gradients has been studied experimentally. It is found that the mixing of the elliptical jet is higher than that for the equivalent circular jet at all the levels of expansion. The decay of elliptic jet is significantly higher than the equivalent circular jet in all three zones of the jet field – the core, characteristic decay and fully developed regions. The reason for the faster decay of the elliptic jet is found to be the continuous variation in the size of the mixing-promoting vortices shed from the nozzle exit owing to its azimuthal asymmetry. The evolution of the jet and its axis-switching phenomenon has been studied using iso-pitot pressure contours taken at different axial locations in the plane normal to the jet axis. As expected, the elliptic jet spreads faster along the minor axis plane than the major axis plane, leading to axis-switching at all the levels of expansion studied. The axis-switching of the elliptic jet shifts upstream with increase in nozzle pressure ratio (NPR) from 4 to 5; from 5 to 7, it shifts downstream. But at marginally under-expanded condition of NPR 8, the axis-switching is found to shift slightly upstream. The occurrence of axis-switching in the elliptic jet indicates enhanced near-field mixing, compared to the equivalent circular jet. The shadowgraph pictures of the jet reveal that the waves prevailing in the elliptic jet are significantly weaker than those in the circular jet.

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OKAMURA, Shoichi. "Configuration Optimization of a Planar-Axis Stellarator with a Reduced Shafranov Shift." Plasma and Fusion Research 8 (2013): 2402029. http://dx.doi.org/10.1585/pfr.8.2402029.

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Kasyutich, Vasili L., and Philip A. Martin. "On quantitative measurements in phase-shift off-axis cavity-enhanced absorption spectroscopy." Chemical Physics Letters 446, no. 1-3 (September 2007): 206–11. http://dx.doi.org/10.1016/j.cplett.2007.08.032.

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Bruns, Donald G. "Using Arago’s spot to monitor optical axis shift in a Petzval refractor." Applied Optics 56, no. 8 (March 3, 2017): 2074. http://dx.doi.org/10.1364/ao.56.002074.

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CARNABUCI, Cristina, Rosalba TOGNETTI, Tommaso VEZZOSI, Federica MARCHESOTTI, Valentina PATATA, and Oriol DOMENECH. "Left shift of the ventricular mean electrical axis in healthy Doberman Pinschers." Journal of Veterinary Medical Science 81, no. 4 (2019): 620–25. http://dx.doi.org/10.1292/jvms.18-0699.

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Sherwood, Mark H., D. W. Alderman, and David M. Grant. "Two-dimensional chemical-shift tensor correlation spectroscopy. Multiple-axis sample-reorientation mechanism." Journal of Magnetic Resonance (1969) 84, no. 3 (October 1989): 466–89. http://dx.doi.org/10.1016/0022-2364(89)90114-5.

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Klayaubol, Warut, and Monsak Pimsarn. "Design of opener shape for improving gimbal tongue shift on y-axis." IOP Conference Series: Materials Science and Engineering 1137, no. 1 (May 1, 2021): 012047. http://dx.doi.org/10.1088/1757-899x/1137/1/012047.

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Mohawk, Jennifer A., Katherine Cashen, and Theresa M. Lee. "Inhibiting cortisol response accelerates recovery from a photic phase shift." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 288, no. 1 (January 2005): R221—R228. http://dx.doi.org/10.1152/ajpregu.00272.2004.

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Jetlag results when a temporary loss of circadian entrainment alters phase relationships among internal rhythms and between an organism and the outside world. After a large shift in the light-dark (LD) cycle, rapid recovery of entrainment minimizes the negative effects of internal circadian disorganization. There is evidence in the existing literature for an activation of the hypothalamic-pituitary-adrenal (HPA) axis after a photic phase shift, and it is possible that the degree of HPA-axis response is a determining factor of reentrainment time. This study utilized a diurnal rodent, Octodon degus, to test the prediction that the alteration of cortisol levels would affect the reentrainment rate of circadian locomotor rhythms. In experiment 1, we examined the effects of decreased cortisol (using metyrapone, an 11β-hydroxylase inhibitor) on the rate of running-wheel rhythm recovery after a 6-h photic phase advance. Metyrapone treatment significantly shortened the length of time it took animals to entrain to the new LD cycle (11.5% acceleration). In experiment 2, we examined the effects of increased cortisol on the rate of reentrainment after a 6-h photic phase advance. Increasing plasma cortisol levels increased the number of days (8%) animals took to reentrain running-wheel activity rhythms, but this effect did not reach significance. A third experiment replicated the results of experiment 1 and also demonstrated that suppression of HPA activity via dexamethasone injection is capable of accelerating reentrainment rates by ∼33%. These studies provide support for an interaction between the stress axis and circadian rhythms in determining the rate of recovery from a phase shift of the LD cycle.

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Friedman, Y., E. Yudkin, I. Nowik, I. Felner, H. C. Wille, R. Röhlsberger, J. Haber, et al. "Synchrotron radiation Mössbauer spectra of a rotating absorber with implications for testing velocity and acceleration time dilation." Journal of Synchrotron Radiation 22, no. 3 (April 3, 2015): 723–28. http://dx.doi.org/10.1107/s1600577515001411.

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Many Mössbauer spectroscopy (MS) experiments have used a rotating absorber in order to measure the second-order transverse Doppler (TD) shift, and to test the validity of the Einstein time dilation theory. From these experiments, one may also test the clock hypothesis (CH) and the time dilation caused by acceleration. In such experiments the absorption curves must be obtained, since it cannot be assumed that there is no broadening of the curve during the rotation. For technical reasons, it is very complicated to keep the balance of a fast rotating disk if there are moving parts on it. Thus, the Mössbauer source on a transducer should be outside the disk. Friedman and Nowik have already predicted that the X-ray beam finite size dramatically affects the MS absorption line and causes its broadening. We provide here explicit formulas to evaluate this broadening for a synchrotron Mössbauer source (SMS) beam. The broadening is linearly proportional to the rotation frequency and to the SMS beam width at the rotation axis. In addition, it is shown that the TD shift and the MS line broadening are affected by an additional factor assigned as thealignment shiftwhich is proportional to the frequency of rotation and to the distance between the X-ray beam center and the rotation axis. This new shift helps to align the disk's axis of rotation to the X-ray beam's center. To minimize the broadening, one must focus the X-ray on the axis of the rotating disk and/or to add a slit positioned at the center, to block the rays distant from the rotation axis of the disk. Our experiment, using the57Fe SMS, currently available at the Nuclear Resonance beamline (ID18) at the ESRF, with a rotating stainless steel foil, confirmed our predictions. With a slit installed at the rotation axis (reducing the effective beam width from 15.6 µm to 5.4 µm), one can measure a statistically meaningful absorption spectrum up to 300 Hz, while, without a slit, such spectra could be obtained up to 100 Hz only. Thus, both the broadening and the alignment shift are very significant and must be taken into consideration in any rotating absorber experiment. Here a method is offered to measure accurately the TD shift and to test the CH.

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McCain, E. R., and D. R. McClay. "The establishment of bilateral asymmetry in sea urchin embryos." Development 120, no. 2 (February 1, 1994): 395–404. http://dx.doi.org/10.1242/dev.120.2.395.

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Although much is known about the specification and determination of the two primary axes (animal/vegetal and dorsoventral or oral/aboral) in a number of embryos, little is understood about bilaterality. In the sea urchin, left/right asymmetry is crucial to normal development as the echinus or adult rudiment is positioned on the left side of the larva. We examined the establishment of bilateral asymmetry in Lytechnis variegatus embryos by determining the relationship of the first cleavage planes to the left/right axis. Embryos were bisected at different times to determine when the bilateral axis is committed. These lineage tracing and cell separation experiments demonstrated that the first cleavage plane divides the embryo into left and right halves, although this is conditional until after late blastula stage. The relationship between the specification of the dorsoventral axis and the bilateral axis was examined experimentally. In other species when the dorsal and ventral halves of early echinoderm embryos (preblastula) are separated, the dorsal half often reverses (180°) its dorsoventral axis. We asked whether those larvae with an inverted dorsoventral axis would shift the position of the echinus rudiment from the original left side to the new left side. If so, it would demonstrate that the larval asymmetry is dependent upon specification of the dorsoventral axis. Using a combination of lineage tracing and cell separation techniques, we show that the left/right asymmetry is specified with respect to the dorsoventral axis.

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Chow, James C. L., Grigor N. Grigorov, and Kathryn Ross. "Dosimetric changes induced by positional uncertainty of cutout in electron radiotherapy." Journal of Radiotherapy in Practice 7, no. 3 (September 2008): 133–40. http://dx.doi.org/10.1017/s1460396908006353.

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AbstractDosimetric changes caused by the positional uncertainty of centring a small electron cutout to the machine central beam axis (CAX) of the linear accelerator (linac) were investigated. First, six circular cutouts with 4 cm diameter were made with their centres shifted off from the machine CAX for 0, 2, 4, 6, 8 and 10 mm using the 6 × 6 cm2 applicator. Then, the percentage depth doses (PDDs) at the machine CAX and cutout centre were measured using the 4, 9 and 16 MeV clinical electron beams produced by a Varian 21 EX linac. The cross- and in-line axis beam profiles were measured at depth of maximum dose (dm) and source-to-surface distance equal to 100 cm using a scanning water tank system and diode detector. When the cutout centre was shifted away from machine CAX for the electron beam with low energy of 4 MeV, the dm, depths of the 80 (R80) and 90% (R90) depth dose at the machine CAX had no significant change (<0.1 mm). For higher energies of 9 and 16 MeV beams, the dm were reduced with 0.45 and 1.63 mm per mm off-axis shift between the cutout centre and the machine CAX, respectively. The R80 and R90 were reduced with 0.7 mm per mm off-axis shift for both energies. When there was a 4 mm off-axis shift, the relative output factors for the 4, 9 and 16 MeV beams were reduced with 0.8, 1.6 and 0.5%, respectively. The isodose coverage of the in-line axis beam profile was reduced when the cutout centre was shifted away from machine CAX. It is important for radiation oncologists, dosimetrists, therapists and physicists to note such dosimetric changes in the electron radiotherapy to the patient, because such positional uncertainty is unavoidable in fabricating an electron cutout in the mould room.

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Şaka, I., Ö. Tezel, and A. Gençten. "A Theoretical Application of 3D J-Resolved NMR Spectroscopy for ISnKm (I = 1/2, S = 1/2 and 1, K = 3/2) Spin Systems." Zeitschrift für Naturforschung A 58, no. 2-3 (March 1, 2003): 139–43. http://dx.doi.org/10.1515/zna-2003-2-311.

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In 3D J-resolved NMR spectroscopy, the chemical shift along one axis and the spin-spin coupling parameters along the two other different axes are resolved. Product operator theory is used for the analytical description of multi-dimensional NMR experiments on weakly coupled spin systems. In this study, the product operator description of heteronuclear 3D J-resolved NMR spectroscopy of weakly coupled ISn Km (I = 1/2, S = 1/2 and 1, K = 3/2) spin systems is presented.

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Roth, S., and T. Schupbach. "The relationship between ovarian and embryonic dorsoventral patterning in Drosophila." Development 120, no. 8 (August 1, 1994): 2245–57. http://dx.doi.org/10.1242/dev.120.8.2245.

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In Drosophila, the dorsoventral asymmetry of the egg chamber depends on a dorsalizing signal that emanates from the oocyte. This signal is supplied by the TGF alpha-like gurken protein whose RNA is localized to the dorsal-anterior corner of the oocyte, gurken protein is the potential ligand of the Drosophila EGF receptor homolog (torpedo), which is expressed in the follicular epithelium surrounding the oocyte. Here, we describe how changes in the dorsalizing germ-line signal affect the embryonic dorsoventral pattern. A reduction in strength of the germ-line signal as produced by mutations in gurken or torpedo does not change the slope of the embryonic dorsoventral morphogen gradient, but causes a splitting of the gradient ventrally. This leads to embryos with two partial dorsoventral axes. A change in distribution of the germ-line signal as caused by fs(1)K10, squid and orb mutations leads to a shift in the orientation of the embryonic dorsoventral axis relative to the anterior-posterior axis. In extreme cases, this results in embryos with a dorsoventral axis almost parallel to the anterior-posterior axis. These results imply that gurken, unlike other localized cytoplasmic determinants, is not directly responsible for the establishment of cell fates along a body axis, but that it restricts and orients an active axis-forming process which occurs later in the follicular epithelium or in the early embryo.

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Journal articles on the topic 'Shift of axis'

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