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起潮力はベクトルと周期性という2つの力学的特性をもつ。周期的な外力が物体に作用すると，一般にその物体は強制振動を起こす。起潮力は周期性をもつ外力であるので，潮汐は強制振動現象でなければならない。この論文では，潮汐の起源について3つの提案を行った。 (1) 海洋潮汐は水深によって3つのタイプに分類される。すなわち，「逆位相型（水深22000ｍ未満）」，「同位相型（水深22000ｍ以上）」，および「共振型（水深22000ｍ）」である。地球の海洋で発生する潮汐は逆位相型の潮汐である。一方，固体地球に起こる地球潮汐は同位相型である。 (2) それぞれの型の潮汐に見られる力学的運動像の違いを明らかにした。広く普及している潮汐論の説明とは違って，実際の潮汐に伴う海水面の変化は，月の位置に従って楕円形と円形を繰り返す楕円振動を行う。その結果，潮汐による海水面の上下動は赤道に沿って互いに90°離れた4領域で起こり，それらの間にはほとんど潮汐運動を起こさない無潮域が出現す る。 (3) 「潮汐バースト」という新しい概念を提唱し，その科学的意義について考察した。自転周期の遅れから推定すると，海洋に潮汐バーストによる巨大潮汐が発生するのは約45億年後と予想することができる。また，この理論を固体地球に適用すれば，原始地球の自転周期が約2時間より短いことはなかったと考えなければならない。, A tide –generating force has two dynamic properties. One of them is a property as a vector with magnitude and direction, the other is a periodicity of force acting with a cycle of about 12 hours. If the tide-generating force is a periodic external force, the tides must be a kind of forced oscillation phenomena. Three proposals regarding the origin of tides will be suggested in this article. (1) The ocean tides can be divided into three types by the depth. They are ‘out of phase’ type (shallower than 22,000m), ‘in phase’ type (deeper than 22,000m) and ‘resonance’ type (equal to 22,000m). The actual ocean tides are classified into the ‘out of phase’ type. On the other hand, the Earth tides occurring on the solid Earth are classified into the ‘in phase’ type. (2) Dynamic movement pictures of each type of tides have been determined. Unlike the widely accepted explanation, the global form of the ocean surface repeats an oval and a circle in turn according to the Moon’s position. As a result, the tidal movements of the ocean will occur in fixed four areas with an angular distance of 90 degrees apart along the equator, and four spots escaping any tidal movements will appear between them. (3) A new concept of ‘tide burst’ is deduced and its scientific meanings are discussed. Judging from the delay of Earth’s rotation period, the tide burst will happen in the ocean about 4.5 billion years from the present.

In this letter, we present a 3-dB power divider with isolated port. The input port is a rectangular waveguide and two output ports are microstrip lines. The measured results of the power divider show above 12-dB minimum isolation over 13-16 GHz, with an input return loss of better than 15 dB. The return loss of the output ports is better than 10 dB, with an insertion loss of lower than 0.35 dB. A maximum amplitude imbalance of about 0.15 dB is observed within 13-16 GHz, with a phase imbalance of better than 2.5°. The proposed power divider in this letter is compact and good integration with the monolithic microwave integrated circuit (MMIC) devices.

The effect of hepatic steatosis on the gradient-echo (GRE) based Modified Look-Locker Inversion Recovery (MOLLI) technique for T1 mapping has not been evaluated. The purpose of this study was to evaluate a GRE based MOLLI technique for hepatic T1 mapping and determine the relationship of T1 differences (ΔT1) on in-phase (IP) and out-of-phase (OP) to fat fraction (FF) measurement.3 T MRI included MOLLI T1 mapping with TE = 1.3 (OP), 2.4 (IP), and 1.8 ms, and chemical-shift-encoded sequence with spectral modeling of fat to generate FF map as a reference. Bloch simulations and oil/water phantoms were used to characterize the response of the MOLLI T1 in various FF 30% since MOLLI T1 estimation was erratic beyond this limit. Curve fit between ΔT1 and FF from simulation was applied to validate the phantom and the in-vivo results. Thirty-eight normal volunteers were included (16 women, Age 44 ± 12 years, BMI 27 ± 5.3 kg/mPhantom results were consistent with the Bloch simulations. The simulated relationship between FF (0-30%) and ΔT1 could be modeled precisely by a cubic equation with R2 = 1. In-vivo MOLLI ΔT1 and estimated FF were correlated to the reference FF (both R2 ≥ 0.96 and P 0.001). TE = 1.8 ms demonstrated less T1 bias (-1.34%) compared to TE = OP (5.32%) or IP (-3.8%, both P 0.001).At 3 T, TE of 1.8 ms can be used to reduce the T1 bias and deliver consistent T1 values when FF is30%.

During elite-level hammer throws, the vertical displacement of the centre of mass (COM) of the thrower and hammer are approximately 180° out of phase (the hammer's COM is at its high point when the thrower's COM is at its low point, and vice versa) prior to the hammer's release. This out-of-phase coordination pattern contributes to the velocity of the hammer, which ultimately contributes to the distance thrown. Several drills are used to improve coordination between the thrower's and hammer's COM, but it is not currently known if the out-of-phase pattern is present during these drills. This study examined the relative phase between the COM of the hammer and thrower during two different rotational drills: The Double Hammer Head and Single Arm drills. Using a 12-camera motion analysis system, COM kinematics for both the hammer and thrower were examined for seven NCAA Division I throwers during the two drills. Contrary to their purported purpose, the phase angles between thrower's and hammer's COM were significantly different from 180° during both drills. Further research should be conducted to examine the mechanical factors of hammer throwing drills, as well as the effect such drills have when implemented within training programs.

This study presents a comprehensive analysis of the synergistic impacts of the Atlantic multidecadal oscillation (AMO) and Pacific decadal oscillation (PDO) on the interdecadal variations of summer rainfall in Northeast Asia. Following the construction of four probable scenarios under various combinations of the AMO and PDO phases, it is found that when the AMO and PDO are out of phase, both of them induce a strong or weak East Asian summer monsoon and a low or high pressure system over Northeast Asia through atmospheric teleconnection, which results in significant wet or dry conditions over the whole of Northeast Asia through the effects of superimposition. In contrast, when the AMO and PDO are in-phase, they induce moderate and regional wet or dry conditions in Northeast Asia, and only a slightly strong or weak East Asian summer monsoon through the effects of cancellation. During the mid-1960s–1990s, a period of drought first began in Northeast Asia under a negative AMO and negative PDO in the mid-1960s, which then increased in severity under a negative AMO and positive PDO in the 1980s, before finally coming to an end under a positive AMO and negative PDO in the late 1990s. The interdecadal predictability of summer rainfall in Northeast Asia may reside in the interdecadal behavior of the North Atlantic and Pacific Oceans.

The fidelity of the eight Asia-Pacific Economic Cooperation (APEC) Climate Center (APCC) models in representing the inter-annual variability and decadal shift in the northeast monsoon (NEM; October–December) rainfall over Southern Peninsular India (SPI) is evaluated. The hindcast data is used for the period of 28 years from 1983 to 2010 based on September initial conditions. The observations showed a clear inter-annual and inter-decadal variability of NEM rainfall during the study period. The analysis suggests that most of the models exhibited poor skill in representing the inter-annual variability. Only APCC model rainfall is in phase with observed SPI rainfall variations on the inter-annual time scale. It is noticed from the observed NEM rainfall time series that the period 1990–1999 (first decade) displays an above-normal rainfall and the period 2000–2010 (second decade) displays a below normal rainfall over the SPI region. It is also evident from the observations that NEM rainfall for most of the years displayed negative anomalies in the second decade including El Nino and La Nina years, while in the first decade positive anomalies are noted, suggesting the presence of decadal variability in the NEM. Rainfall variations in most of the coupled models are in phase with the observations during the second decade but are out of phase during the first decade. As evidenced from the observations that the intensified deep convection over the Indo-western Pacific region results in too far southward movement of the intertropical convergence zone (ITCZ) during the second decade. The southward shift in the strong upper-level divergence associated with lower-level convergence over the south Indian Ocean caused negative rainfall anomalies over the SPI in this decade. Further, the difference between the second and first decade demonstrates that an anomalous anticyclonic circulation over the Indian subcontinent is accountable for the vigorous dry northerly flow towards the SPI region and the resultant decadal shift in the rainfall pattern. Though the southward shift in the rainfall and large-scale circulation patterns are mildly captured by some models from decade to decade, most of the models completely misrepresented it. This study suggests that the coupled models displayed a very limited skill not only in capturing the inter-annual variability but also in representing the decadal variability of NEM rainfall.

PURPOSE: This study aimed to (i) develop Magnetization-Prepared Golden-angle RAdial Sparse Parallel (MP-GRASP) MRI using a stack-of-stars trajectory for rapid free-breathing T1 mapping and (ii) extend MP-GRASP to multi-echo acquisition (MP-Dixon-GRASP) for fat/water-separated (water-specific) T1 mapping. METHODS: An adiabatic non-selective 180° inversion-recovery pulse was added to a gradient-echo-based golden-angle stack-of-stars sequence for magnetization-prepared 3D single-echo or 3D multi-echo acquisition. In combination with subspace-based GRASP-Pro reconstruction, the sequence allows for standard T1 mapping (MP-GRASP) or fat/water-separated T1 mapping (MP-Dixon-GRASP), respectively. The accuracy of T1 mapping using MP-GRASP was evaluated in a phantom and volunteers (brain and liver) against clinically accepted reference methods. The repeatability of T1 estimation was also assessed in the phantom and volunteers. The performance of MP-Dixon-GRASP for water-specific T1 mapping was evaluated in a fat/water phantom and volunteers (brain and liver). RESULTS: ROI-based mean T1 values are correlated between the references and MP-GRASP in the phantom (R(2) = 1.0), brain (R(2) = 0.96), and liver (R(2) = 0.73). MP-GRASP achieved good repeatability of T1 estimation in the phantom (R(2) = 1.0), brain (R(2) = 0.99), and liver (R(2) = 0.82). Water-specific T1 is different from in-phase and out-of-phase composite T1 (composite T1 when fat and water signal are mixed in phase or out of phase) both in the phantom and volunteers. CONCLUSION: This work demonstrated the initial performance of MP-GRASP and MP-Dixon-GRASP MRI for rapid 3D T1 mapping and 3D fat/water-separated T1 mapping in the brain (without motion) and in the liver (during free breathing). With fat/water-separated T1 estimation, MP-Dixon-GRASP could be potentially useful for imaging patients with fatty-liver diseases.

Background The aim of this study was to assess the added value of chemical shift imaging when used with routine MRI study in evaluation of bone marrow changes in SCD. Forty-two patients with SCD and bone pain were included in the study; they underwent CSI and routine MRI study on the symptomatic anatomic part of the skeleton. Results Four patterns of diffuse bone marrow changes were recognized; they varied from persistent red marrow to diffuse hypointense patterns with abnormal signal loss percentage on CSI that suggest presence of iron overload (n = 28, 66.6%). Serum ferritin level was increasing in accordance to the degree of signal changes found on CSI with significant high negative correlation between the percentage of signal loss on CSI obtained from IP-OP/IP formula and serum ferritin level. In focal marrow lesions, all T1 hyperintense lesions demonstrated corresponding hyperintensity on IP and OP; the detection frequency on CSI was relatively higher on OP compared with IP images. Conclusion CSI has high diagnostic performance in detecting diffuse marrow changes and development of iron overload in SCD. In SCD-related focal marrow lesions, CSI could have a complementary role in detection of T1 hyperintensity and lesion conspicuity.

Although acknowledged to be a simplification, the rate of sediment supply is usually assumed to be constant in sequence stratigraphic interpretations of clastic shelf systems. The simplified assumption taken in this work is that sediment supply can be represented by sine curves linked to climate changes driven by Milankovitch cycles. Three orders of sediment supply sine curves (amplitude and frequency scaled to order) are convolved with three orders of Milankovitch-forced eustatic sea-level sine curves and a constant rate of subsidence to generate curves for the ratio of rate of accommodation development to rate of sediment supply (δ A /δ S ). The relative-sea-level curve is then held constant whilst sediment supply is systematically changed from being constant to being cyclical across the three orders of Milankovitch frequencies and being in-phase, and out-of-phase with the eustatic cycles by 90°, 180°, and 270°. For each scenario, stratal architecture is then represented for sixty consecutive parasequences (fifth-order, regressive–transgressive shelf transit cycles) by converting the δ A /δ S curves into pseudo thickness / sandstone fraction plots (TSF plots). Constant sediment supply, in-phase sediment supply, and 180°-out-of-phase sediment supply produce symmetrical stratal geometries with equal periods of progradation, aggradation, and retrogradation. When sediment-supply cycles are 90°-out-of-phase (supply peak occurs later than sea-level peak), stratal geometries are asymmetrical with progradational architectures being dominant. When sediment-supply cycles are 270°-out-of-phase (supply peak occurs earlier than sea-level peak), stratal geometries are also asymmetrical but retrogradational architectures are dominant. These patterns are reproduced at all three orders of stratigraphic hierarchy (parasequence, sequence, and composite sequence). Comparison of these synthetic stratal geometries to real-world stratal geometries from Triassic to Neogene rocks across both the fifth-order (parasequence) and fourth-order (sequence) of stratal hierarchies suggests a consistently occurring asymmetrical, progradation-dominant motif. This indicates that 90°-out-of-phase sediment supply (supply peak occurs later than sea-level peak) may be a common occurrence through geological time. The work also corroborates the findings of earlier workers and suggests that sequence stratigraphic surfaces can change nature along depositional strike due to out-of-phase sediment supply and can thus also be diachronous. This work conceptually illustrates that Milankovitch climate-change-induced sinusoidal-sediment-supply cycles, out-of-phase with sinusoidal eustatic-sea-level cycles, may produce commonly observed asymmetrical stratal architectures and should be considered when invoking causal mechanisms for stratal architectures on clastic shelves.

In a conventional power divider, power dividing network and isolation network are usually independent of each other. To reduce the size of out-of-phase power divider with arbitrary power ratio, coupled microstrip lines are proposed to facilitate power dividing and isolation of a power divider simultaneously in this article. Formulations have been derived for the proposed out-of-phase power divider with arbitrary ratio. Two compact power dividers are implemented on the printed circuit board (PCB) with power ratio $k^{2} = 9$ and $k^{2} = 1000$ . It can be observed that there is a satisfactory agreement between the simulated and measured results.

Intra-medullary tumour length is accurately assessed on T1-weighted turbo spin echo (T1W TSE) MRI which can be relatively time consuming, whilst the gradient echo Dixon (T1W GrE Dixon) technique is a rapid sequence (imaging time ~ 30 s). The aim of this study was to determine if the out-of-phase Dixon (OP T1W GrE Dixon) sequence can produce equivalent measurements of intra-medullary tumour length compared to the T1W TSE sequence. Tumour length was assessed in 90 patients undergoing MRI for staging of primary bone tumours with both T1W TSE and OP T1W GrE Dixon MRI sequences at 3 T (n = 42) and 1.5 T (n = 48). Tumour length was measured independently by different observers allowing assessment of inter-observer correlation, and the correlation between measurements on T1W TSE and OP T1W GrE Dixon sequences was also determined. There were 53 males and 37 females (mean age 36.4 years; range 2–77 years). Inter-observer correlation for tumour length on both the T1W TSE and T1W OP GrE Dixon sequences was very good (ICC = 0.94–0.98), and measurement of tumour length comparing T1W TSE and T1W GrE Dixon was also very good (ICC = 0.91–0.99). In 4 cases, tumour length was significantly overestimated on T1W TSE images due to extensive reactive marrow oedema, but more accurately determined on the OP sequence when compared to resection specimens. The OP T1W GrE Dixon sequence is comparable to T1W TSE for assessment of the intra-medullary length of appendicular bone tumours, and more accurate in the presence of extensive reactive marrow oedema.

Purpose The purpose of this prospective study was to determine whether chemical shift gradient-echo magnetic resonance imaging (MRI) could predict glioma grade. Materials and methods A total of 69 patients with 69 gliomas were prospectively included. There were 41 men and 28 women with a mean age of 50 ± (SD) years (range: 16–82 years). All patients had MRI of the brain including chemical shift gradient-echo sequence, further referred to as in- and out-of phase sequence (IP/OP). Intravoxel fat content was estimated by signal loss ratio (SLR = [IP-OP]/2IP), between in- and out-of-phase images, using a region of interest placed on the viable portion of the gliomas. Association between SLR and glioma grade was searched for using Wilcoxon and Mann–Whitney U tests and diagnostic capabilities using area under the receiver operating characteristic (AUROC) curves. Results A significant association was found between SLR value and glioma grade (P 9‰ allowed complete discrimination between grade III and grade II glioma with 100% specificity (95% CI: 85–100%), 100% sensitivity (95% CI: 78–100%) and 100% accuracy (95% CI: 90–100%) (AUROC = 1). A SLR > 20‰ allowed discriminating between grade IV and grade III glioma with 75% specificity (95% CI: 57–89%), 73% sensitivity (95% CI: 45–92%) and 72% accuracy (95% CI: 57–84%) (AUC = 0.825, 95% CI: 0.702–0.948). The AUROC for the diagnosis of high-grade glioma (grade III and IV vs. grade II) was 1. Conclusion Chemical shift gradient echo MRI provides accurate grading of gliomas. This simple method should be used as a biomarker to predict glioma grade.

AC loss is an intractable and inevitable issue on high temperature superconducting (HTS) coils. In some HTS devices with the iron core, AC loss in HTS coils have been investigated. However, practically, partial distorted currents can flow in HTS coils, and the AC loss in this situation has rarely been conducted. Here, a normal and distorted current were respectively applied into a double-layer racetrack coil (DRC) to induce AC losses. The numerical and experimental results were obtained with and without laminated silicon steel sheets (LSSS), which showed that the AC loss of the DRC significantly increased when put on the LSSS. Furthermore, compared with the loss generated by the fundamental waveform, currents with 3rd harmonic in phase and 5th out of phase, both with 10% total harmonic distortion (THD) could increase AC loss by 9.3% and 7.8%, respectively. To reduce AC loss of the DRC on the LSSS, two methods are proposed, and it is found that increasing the 5 mm distance vertically and horizontally between the DRC and LSSS could significantly decrease the AC loss by 20.7% and 18.0%, respectively. This study could offer an indispensable reference for designing and operating HTS coils with the iron core for AC applications.

Out-of-phase ventilation occurs when local regions of the lung reach their maximum or minimum volumes at breathing phases other than the global end inhalation or exhalation phases. This paper presents the N-phase local expansion ratio (LER $_{N}$ ) as a surrogate for lung ventilation. A common approach to estimate lung ventilation is to use image registration to align the end exhalation and inhalation 3DCT images and then analyze the resulting correspondence map. This 2-phase local expansion ratio (LER2) is limited because it ignores out-of-phase ventilation and thus may underestimate local lung ventilation. To overcome this limitation, LER $_{N}$ measures the maximum ratio of local expansion and contraction over the entire breathing cycle. Comparing LER2 to LER $_{N}$ provides a means for detecting and characterizing locations of the lung that experience out-of-phase ventilation. We present a novel in-phase/out-of-phase ventilation (IOV) function plot to visualize and measure the amount of high-function IOV that occurs during a breathing cycle. Treatment planning 4DCT scans collected during coached breathing from 32 human subjects with lung cancer were analyzed in this study. Results show that out-of-phase breathing occurred in all subjects and that the spatial distribution of out-of-phase ventilation varied from subject to subject. For the 32 subjects analyzed, 50% of the out-of-phase regions on average were mislabeled as low-function by LER2 (high-function threshold of 1.1, IOV threshold of 1.05). 4DCT and Xenon-enhanced CT of four sheep showed that LER8 is more accurate than LER2 for measuring lung ventilation.

We investigate the multiphoton coherence effects on two weak probe-beam transitions in a five-level double-inverted Y system, where the two probe transitions are also affected by phase-dependent χ(3) processes occurring via Λ and Ξ channels. This system provides two channels to create each two-photon coherence and three-photon coherence. We show that quantum interference induced by the closed loop structure formed by excited states enhance the effect of two-photon coherence. Conditions on probe and control beam Rabi frequencies are provided to remove this quantum interference effect and achieve a balance between absorption induced by three-photon coherence and gain due to χ(3) processes either via two channels or via one channel. When the control beams forming double-Λ-configuration are out of phase with each other and so are the control beams forming double-Ξ-configuration, the probe beams are shown to undergo correlated absorption mainly due to χ(3) contribution. Also we present absorption profiles of both probe beams for moving atoms to show the multiphoton coherence effects.

Background/aim: CAIPIRINHA is a new technique in abdominal imaging. Pancreatic steatosis PS is a subject of increasing scientific interest. The aim of this study was to investigate the efficacy of the isotropic 3D-VIBE- CAIPIRINHA -DIXON technique on a new generation 3-tesla MR unit in the evaluation of PS.Materials and methods: In this retrospective study, the imaging findings of 49 patients with PS and 41 control subjects were examined. The pancreas-to-spleen ratio PSR , pancreas-to-muscle ratio PMR , and pancreatic signal intensity index PSII were defined as 3 new parameters and these indexes were calculated from the in-phase/out of phase 3D-VIBE- CAIPIRINHA-DIXON images. Results: The PSR, PMR, and PSII values were significantly different between the patient and control groups P = 0.001, P = 0.009, P < 0.001, respectively . Statistically significant differences were observed between patient and control groups for ROI measurements of fatty areas on these sequences/images: subtraction in-out P < 0.001 , T2W HASTE P < 0.001 , DIXON-fat P < 0.001 , fat-suppressed T1W P = 0.002 , and subtraction out-in P = 0.010 . Conclusion: Evaluation of PS with the 3D-VIBE-CAIPIRINHA-DIXON technique can be made rapidly and effectively.

The effect of the multiaxiality and proportionality of loading on the cyclic behaviour and early cracking behaviour was studied for closed die forged AZ80 Mg alloy. Several different loading paths were presented, uniaxial and biaxial with varying levels of non-proportionality. In multiaxial loading the effect of proportionality is only present on the shear response of the material and increasing levels of non-proportionality is detrimental to the fatigue life. When compared with proportional loading, a 50% reduction in life was observed under 90° out of phase non-proportional loading. The pure axial cracking behaviour is dominated by transverse cracks along the plane of maximum normal stress, whereas in pure shear the material exhibited longitudinal cracking (shear dominated) behaviour in LCF regime and helical cracking (normal stress dominated) in the HCF regime. The synergistic effects of each individual uniaxial cracking modes contribution towards the combined macroscopic cracking behaviour in multiaxial loading was investigated, and was dominated by transverse cracking when the shear strain energy density (SED) contribution to the total SED was low, and mixed cracking when the shear SED contribution was high.

Background MRI is an excellent imaging modality to evaluate the liver which is vulnerable to a spectrum of neoplastic and nonneoplastic conditions. Out-of-phase T1 weighted (T1W) gradient-echo imaging is a highly accurate technique to distinguish focal hepatic steatosis from neoplastic masses. Aim This study aimed to demonstrate the diagnostic value of gradient-echo in-phase and out-of-phase MRI sequence in the characterization of benign and malignant hepatic focal lesions. Patients and methods This study is carried out on 89 patients with 100 hepatic focal lesions; their ages ranged from 32 to 76 years (mean, ±52 years), who traveled for MRI liver for the diagnosis and characterization of hepatic focal lesions. MR examination was performed including T1WI, T2WI, postcontrast dynamic enhanced T1WI followed by gradient-echo in-/out-of-phase MRI sequences. Results The 100 hepatic focal lesions proved to be: 17 focal fatty infiltration, one lipoma and eight fatty-spared area (FSA), 11 hemangioma, 10 regenerative cirrhotic nodules (RN), eight siderotic liver nodules, 12 dysplastic liver nodules, 23 hepatocellular carcinomas, seven metastatic, and three lymphoma. At conventional MRI, most of the benign hepatic focal lesions exhibit iso/hyperintense signals at T1WI and iso/hypointensity at T2WI. However, nearly all malignant lesions exhibit mainly hypointense signals at T1WI and mild hyperintensity at T2WI. At DCE T1WI: focal fatty infiltration and FSA, RN, and siderotic liver nodules take no enhancement; hemangiomas showed marginal arterial enhancement with gradual filling and there is arterial contrast enhancement with venous washout in hepatocellular carcinomas and arterial enhancement with or without washout in metastatic lesions; however, lymphomatous lesions showed temporary perilesional arterial enhancement with delayed contrast enhancement. The gradient in-/out-of-phase sequence: accurately diagnoses the all fat-containing lesions that showed moderate hyperintensity in the in-phase images and signal loss in out-of-phase images, while FSA exhibit in-phase isointensity and hyperintensity in out-of-phase images while all other benign and malignant hepatic focal lesions revealed hypointense signals in both in-/out-of-phase images. Conclusion Gradient-echo in-/out-of-phase sequence is a simple and noninvasive method that can aid in the diagnosis and characterization of benign and malignant hepatic focal lesions with 100% accuracy in the diagnosis of fat-containing lesions. Also, it can differentiate RN from dysplastic liver nodules that is considered as premalignant lesions and improve the malignant hepatic focal lesion definition.

Purpose The purpose of this study was to test the feasibility of joint space width (JSW) measurement on Dixon MR images with the “India ink” artifact between cartilage and bone marrow as a landmark for the subchondral plate and to correlate it with radiographic JSW. Materials and methods Both hands of six volunteers (three women, three men; mean age, 36.7 ± 10.4 [SD] years) and 24 patients with early rheumatoid arthritis (16 women, 8 men; mean age, 45.7 ± 14.5 [SD] years) were imaged with MRI Dixon sequences and radiographs. Two radiologists (R1, R2) separately measured JSW in 11 joints per hand on all Dixon images in volunteers, on contrast-enhanced T1-weighted out-of-phase images in patients and on radiographs in both groups. Inter-technique, intra-observer and inter-observer agreements were assessed using intraclass correlation coefficient (ICC) and Bland Altman analysis. Results In volunteers, agreement between JSW measurements on MRI and radiographs was the highest with T1-weighted Dixon out-of-phase images (mean ICC ranging from 0.69 to 0.76 for R1 and 0.65 to 0.74 for R2). In patients, median bias between JSW measurements at first and second readings was not statistically significantly different from 0 on T1-weighted Dixon out-of-phase images (mean bias of 0.00 and + 0.01 mm) and radiographs (mean bias of 0.00 and +0.01 mm). Median bias of the difference between measurements of R1 and R2 was statistically significantly different from 0 on T1-weighted Dixon out-of-phase images (mean bias of -0.11 and -0.09 mm; P Conclusion Measurement of hand JSW on T1-weighted Dixon out-of-phase images using India ink artifact as a landmark for the subchondral plate is repeatable and reproducible.

Ultrasonic waves have been used for improved oil recovery especially from the marginal well in so many areas all over the world. The main mechanism is to supply oil molecules by energy to overcome capillary forces there by restructuring the relative permeability curves and increasing the oil mobility. Monitoring these changes is very important for increasing the oil mobility even after residual oil saturation achieved. The present work investigates the laboratory effects of ultrasonic waves on the relative permeability curves. Five sandstone and carbonate cores were used from Egyptian reservoirs. Their permeabilities range from 67 to 460 md. Acoustic ultrasonic waves of 500 KHZ have been applied. At this frequency, the fluid vibrates out of phase with the solid and is forced out through the pore structure in the agglomerate. This relative fluid motion exerts high viscous stresses at the particle-particle contact points which leads to fracture of the agglomerate and the dispersion of the individual particles. This interaction causes changes in relative permeability of the rock to oil and water. Therefore, the results showed that applying ultrasonic waves has a higher effect in permeability reservoirs (76 md to 460 md) and can mobilize additional quantity of crude oil. The fractional flow curve changes are also addressed and analyzed after wave applications. The aim of this research is to investigate the effect of the ultrasonic wave as a new proposed method to improve oil recovery by changing the relative permeability curves of the reservoirs.

Seismic pounding between closely spaced building structures is one among the main causes of severe building damages observed in seismically proven regions. Due to the earthquake-induced vibrations, the buildings which are adjacent to each other with dissimilar dynamic characteristics will move out of phase resulting in the collision as there would be no energy dissipation system to accommodate the relative motions. Seismic pounding can be prevented by passive structural control of energy dissipation systems, i.e., dampers. The current study aims to mitigate the seismic pounding observed in the adjacent buildings connected with fluid viscous dampers (FVDs). G+14 and G+9 multistoried adjacent buildings are modeled and analyzed using ETABS 2017. Two stories are connected with one viscous damper. Adjacent buildings with similar height (G+14 storied) and varying height (G+14 & G+9 storied) connected with FVDs subjected to El Centro earthquake are studied. Nonlinear time history analysis is carried out. Considering displacement and seismic gap as the main parameters, adjacent buildings with similar and different height connected with and without FVDs are compared.

An equation is derived for analyzing the self-action of a wave packets with few optical cycles in multicore fibers (MCF). A new class of stable out-of-phase spatio-temporal solitons with few cycle durations in the MCF with cores located in a ring is found and analyzed. The stability boundary of the obtained solutions is determined. As an example of using such solitons, we considered the problem of their self-compression in the process of multisoliton dynamics in the MCF. The formation of laser pulses with a duration of few optical cycles at the output of a ten-core MCF is shown.

The studies on poleward expansion of the Hadley circulation have mainly concentrated on linear trends with global warming. There is no consensus on how the edge of the Hadley circulation has been affected by the dynamical linkage to causes of change. Here, this study strives to make a robust assessment of the changes in the edge latitude of the Hadley circulation by comparing two reanalysis datasets and two theoretical models, namely the Held and Hou. J Atmos Res 37: 515-533; (1980) model (HH80) and Held (2000) model (He00). A poleward shift in both hemispheres emerged after the mid-1990s in the two reanalysis datasets, except for the Northern Hemisphere from ERA-Interim. Comparing the edge latitudes of the two reanalysis datasets, HH80 (He00) is seen to be out of phase (in-phase) in the Hadley circulation edge. He00 only shows interdecadal change regarding the poleward expansion of the Hadley circulation. We found that the dominant factors affecting change in the edge latitude of the Hadley circulation were the subtropical static stability and subtropical tropopause height. The changes in the Hadley circulation in the Northern Hemisphere (Southern Hemisphere) are associated with negative ENSO and positive AO (positive SAM).

This paper discusses the phase shift effect occurring between two and more load channels of multiaxially loaded specimens. The discussion concludes that there is an extreme shortage of good experimental data that would prove the existence and the trend of the phase shift effect in the high-cycle fatigue region. It is no wonder that there are so many fatigue strength estimation criteria that use quite different computational concepts, because the response to the phase shift effect in the experimental base is often hidden in a conglomeration of other interacting effects. The paper presents results of a sensitivity study that compares the fatigue strength estimation results for various such criteria for the same stress amplitudes, but for different phase shifts between the push-pull and torsion load channels. These results show that, with the exception of criteria, that assume a zero phase shift effect, the phase shift affects the results of each studied fatigue strength estimation criterion in a different way. If well-organized experiments were available, experiments corresponding to the described comparison between in-phase and out-of-phase loading would show the right trends, and the optimum criterion could be selected. A proposal for such an experimental setup is provided in the paper.

Regionalization of river discharges is a process of transferring hydrological information to generalize hydrological information from one river to another. One approach to regionalize river discharge is to use a distance-based regional analysis by employing a Dynamic Time Warping (DTW) dissimilarity measure to cluster homogeneous river discharge patterns based on sequenced of time series discharge data. However, clustering homogeneous river discharge patterns can be sensitive to the choice of distance metric measures used due to out of phase behavior in the discharge time series. In this study, we assess three types of Dynamic Time Warping (DTW) measures specifically conventional DTW, a feature based DTW and a weighted based DTW on four annual discharge time series from six rivers in the state of Johor, Malaysia. A comparison of eight different clustering validation indices to determine the optimal number of rivers clusters with similar discharge patterns. These indices are used to measure the internal and external strength of the identified clusters. The results indicate that weighted based DTW outperform the conventional DTW and feature based DTW with 75% of the clustering indices agree that there are three optimal clusters of river discharge. By using weight as a function in DTW, it helps to cater the out of phase behavior in river discharge time series with the highest agreement of clustering indices compared to other types of DTW measures. We also found that three of the rivers (Sayong, Bekok, and Segamat) have similar river discharge patterns and could be used together in the generalization process. Meanwhile, the other rivers (Johor, Kahang, and Muar) varies in their time series patterns.

In most places extreme high tides undergo a clear seasonal variation. It is well known that semidiurnal tides tend to peak during equinox seasons, and diurnals during solstice seasons. This is a consequence of the solar and lunar declinations, which when large maximize diurnal tides at the expense of semidiurnals. The semiannual range modulation of tidal extremes for a pure semidiurnal tide is determined mainly by the amplitude of the K2 constituent; a pure diurnal is determined mainly by P1. Mixed tidal regimes tend to experience maxima very roughly around the times of solstice, but not always, with the semiannual modulation generally a complicated function of constituent amplitudes and phases. These modulations are here mapped worldwide by analyzing tidal extremes predicted with a global tide model. The known 4.4-year modulation in extreme tides is a consequence of declinational and perigean effects coming in and out of phase. The phase of the 4.4-year modulation is controlled by the phase of the semiannual modulation, irrespective of whether the tide is diurnal, semidiurnal, or mixed.

A concept of decoupling ground (DG) is introduced in this paper to enhance the isolation of massive MIMO antenna arrays. For an array, mutual coupling between array elements can be achieved by the free-space coupling and the coupling currents flowing on the ground plane shared by elements. The isolation in this paper is improved by adjusting the shape of the ground plane under each element to make the mutual coupling from the free space and the ground plane out of phase. In this way, low mutual coupling is realized. As the first example, a single-polarization linear array with 8 elements is designed, simulated and measured to verify the concept as well as the simulation accuracy. The measurements align very well with the simulations. Another two examples of dual-polarization 2×2 and 4×4 square arrays are also given and simulated to demonstrate the effectiveness of the proposed technique. In all of these examples, the isolation can efficiently be enhanced with the DG for all the co-polarization and cross- polarization coupling paths of the massive MIMO elements. Compared with the previous literature, the arrays with the DG method can achieve either much better isolation or a much lowerprofile while keeping the other performance comparable.

In this paper, a new method to develop balanced-to-unbalanced (BTU) filtering out-of-phase power divider (PD) is presented. Based on the comparison between BTU filtering out-of-phase PD and balanced-to-balanced (BTB) filter, it is found that the BTU filtering out-of-phase PD can be constructed by combining a BTB filter and an additional parallel four-port network. The design equations are derived and corresponding circuit models are given. Finally, a prototype is designed to verify the theoretical prediction. The design procedure and parameter selection are detailed. The good performance and the consistency between the simulated and measured results verify the design theory.

International audience; ObjectivesTo improve our understanding of the global epidemiology of common respiratory viruses by analysing their contemporaneous incidence at multiple sites.Methods2010–2015 incidence data for influenza A (IAV), influenza B (IBV), respiratory syncytial (RSV) and parainfluenza (PIV) virus infections were collected from 18 sites (14 countries), consisting of local (n = 6), regional (n = 9) and national (n = 3) laboratories using molecular diagnostic methods. Each site submitted monthly virus incidence data, together with details of their patient populations tested and diagnostic assays used.ResultsFor the Northern Hemisphere temperate countries, the IAV, IBV and RSV incidence peaks were 2–6 months out of phase with those in the Southern Hemisphere, with IAV having a sharp out-of-phase difference at 6 months, whereas IBV and RSV showed more variable out-of-phase differences of 2–6 months. The tropical sites Singapore and Kuala Lumpur showed fluctuating incidence of these viruses throughout the year, whereas subtropical sites such as Hong Kong, Brisbane and Sydney showed distinctive biannual peaks for IAV but not for RSV and PIV.ConclusionsThere was a notable pattern of synchrony of IAV, IBV and RSV incidence peaks globally, and within countries with multiple sampling sites (Canada, UK, Australia), despite significant distances between these sites.

A new design of filtering power divider (FPD) with a pair of highly isolated out-of-phase outputs is presented. By combining the conventional slotline–microstrip transition with microstrip resonators, the proposed FPD is initially constructed. Owing to the field conversion from the slotline to the microstrip line, two signals with equal magnitude and 180° phase difference are simultaneously obtained at two output ports. Specifically, to isolate two output ports, a new isolation network composed of a microstrip line and a grounded resistor is loaded on the differential symmetrical plane. By adopting the even-/odd-mode analysis method, the working principles for both of filtering and isolation are explained with design equations. For demonstration, two prototypes of out-of-phase FPDs operating at 3.4 GHz with 3-dB fractional bandwidths of 8% and 18% are designed, fabricated, and tested, respectively. The simulated and measured results are displayed to verify the theoretical design equations.

The mathematical models of optical diffraction were determined using spectral angular propagation, which are associated with the amplitude distribution of the field diffracted by two circular apertures with different diameters. It establishes the existence of a right and a left diffraction pattern, as well as the out of phase field as it propagates in the (convergent and divergent) Fresnel zones of a spherical lens. Herein, experimental and the simulation resoults are shown.

Effect of in-phase and out of phase cyclic loading on fatigue behaviour was evaluated for 304LN stainless steel using tubular specimens. It was found that additional hardening observed for out of phase loading was a consequence of more grains participating in deformation process. Further, strains in matrix were higher and evenly distributed across grains for out of phase loadings as quantified through misorientation analysis. Disparities in misorientation studies were accounted by substructural development investigated through electron microscopy. Additionally, elastic and plastic strains were found to be out of phase with respect to total strains for out of phase loading.