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Objective: Venous structures of the transverse-sigmoid sinus region have been insufficiently studied by magnetic resonance venography, especially in the healthy Han Chinese population. Methods: Magnetic resonance venography data were reconstructed. The relevant parameters were recorded. A paired t -test was used to compare the diameters of the inferior petrous sinus at the origin and termination. An unpaired t -test, a chi-squared test or Fisher’s exact test was used to compare other data. Results: One hundred healthy participants were included. The average age was 36.6 ± 17.1 years, and the ratio of males to females was 1:1. The development of the transverse-sigmoid sinus had a right-sided predominance in 51% of patients. Statistical analysis revealed significant differences ( p

Objective: The occipital sinus (OS) has many variations. It is unknown whether OS can change the angioarchitecture of torcular Herophili. Therefore, we performed magnetic resonance venography (MRV) in a cohort of Han Chinese individuals to determine whether OS can change the angioarchitecture of torcular Herophili. Methods: Participants were divided into a normal OS group and a hyperplastic OS group. Parameters of the OS and torcular Herophili and its neighboring structures were recorded. Statistical analysis was used to determine the effects of OS on torcular Herophili and neighboring structures. Results: One hundred forty-five healthy participants were enrolled. One hundred patients were in the normal OS group, and 45 were in the hyperplastic OS group. In the normal OS group, the diameters at the transverse sinus (TS) origin were 5.8 ± 2.3 mm on the left side and 7.5 ± 2.2 mm on the right side. In the hyperplastic OS group, the diameters at the TS origin were 6.0 ± 2.1 mm on the left side and 7.0 ± 2.7 mm on the right side. Fenestration was observed in 33% of the torculars in the normal OS group and 6.7% of the torculars in the hyperplastic group. An unpaired t-test revealed a significant difference between bilateral TSs in the normal OS group (P

Abstract Inner product arguments allow a prover to prove that the inner product of two committed vectors equals a public scalar. They are used to reduce the complexity of many cryptographic primitives, such as range proofs. Range proofs are deployed in numerous applications to prove that a committed value lies in a certain range. As core building blocks, their complexity largely determines the performance of corresponding applications. In this paper, we have optimised the inner product argument with statement including two vector commitments (IPAtvc) and range proof of Daza et al. (PKC’20), the inner product argument with statement including only one vector commitment (IPAovc) of Bünz et al. (S&P′18). For IPAtvc, we reduce the concrete communication complexity by 2 log2n field elements, where n is the vector dimension. For range proofs, we reduce the concrete communication and prover complexities by about 2 log2m field elements and 11m field multiplications, respectively, where m is the bit length of range. For IPAovc, we exponentially reduce the asymptotic verifier complexity from linear to logarithmic. Due to the asymptotic characteristics, our protocols are highly competitive when the vector dimension or bit length of range is large.

Objective: The superior sagittal sinus (SSS) is an important structure, but few studies have analyzed it using computed tomography angiography (CTA). Methods: This study was performed to examine the angiographic anatomy of the SSS and its adjacent structures using CTA in Han Chinese participants. According to age, participants were divided into elderly and nonelderly groups. The parameters of the SSS and adjacent structures were measured, recorded and analyzed statistically. Results: A total of 500 Han Chinese participants were enrolled in this study, including 346 in the elderly group and 154 in the nonelderly group. In the elderly group, regarding inferior sagittal sinus (ISS) development, 187 ISSs were absent, 85 were visible, and 74 were clear. In the nonelderly group, 62 ISSs were absent, 54 were visible, and 38 were clear. In the elderly group, the Rolandic bridging vein diameter was 3.6 ± 0.8 mm; in the nonelderly group, the diameter was 3.9 ± 1.1 mm. The statistical results showed a difference in ISS development between the elderly and nonelderly groups (P

Middle cerebral artery (MCA) aneurysms are complex and widely distributed throughout the course of the MCA. Various types of aneurysms can occur in the MCA. Ruptured as well as unruptured MCA aneurysms may require treatment to avoid bleeding or rebleeding. Currently, clipping is regarded as the first-line choice for the treatment of MCA aneurysms. However, endovascular treatment (EVT) is emerging as an alternative treatment in selected cases. EVT techniques vary. Therefore, it is necessary to review EVT for MCA aneurysms. In this review, the following issues were discussed: MCA anatomy and anomalies, classifications of MCA aneurysms, the natural history of MCA aneurysms, EVT status and principle, deployments of traditional coiling techniques and flow diverters (FDs), and deployments and prospects of intrasaccular flow disruptors and stent-like devices. According to the review and our experience, traditional coiling EVT is still the preferred therapy for most MCA aneurysms. FD deployment can be used in selective MCA aneurysms. Parent artery occlusion (PAO) can be used to treat distal MCA aneurysms. In addition, new devices can be used to treat MCA aneurysms, such as intrasaccular flow disruptors and stent-like devices. In general, EVT is gaining popularity as an alternative treatment option; however, there is still a lack of evidence regarding EVT, and longer-term data are not currently available for most EVT devices.

Supraclinoid internal carotid artery (ICA) fenestration aneurysm is rare. Except for open surgery, endovascular treatment (EVT) is considered an alternative for such an aneurysm. However, experience with this procedure is lacking. Therefore, we reported such a case. A 61-year-old woman suffered subarachnoid hemorrhage. Digital subtracted angiography (DSA) showed bilateral middle cerebral artery (MCA) aneurysms and a saccular aneurysm associated with fenestration of the supraclinoid ICA. Two MCA aneurysms were treated with single coiling, and the supraclinoid ICA fenestration aneurysm was coiled under stent assistance. The postoperative recovery was uneventful. At this time, a literature review was performed on the role of EVT in supraclinoid ICA fenestration aneurysms. A total of 13 supraclinoid ICA fenestration aneurysms treated by EVT in 11 cases, including our case, were obtained. After EVT, good outcomes were obtained in all cases. To our knowledge, this is the first study to review the role of EVT for supraclinoid ICA fenestration aneurysms. Our case report and literature review indicated that EVT for such aneurysms may be feasible and act as a therapeutic alternative.

Dural arteriovenous fistula (DAVF) of the inferior petrosal sinus (IPS) is very unusual. Endovascular embolization is a good option for the treatment of DAVF. Until now, DAVFs of the IPS have only been reported sporadically. We reported two such cases. Case 1 was a 48-year-old man with headache and diplopia. Angiography confirmed a DAVF of the distal IPS, mainly supplied by the occipital artery (OA), and the IPS was occluded, which retrogradely drained into the cavernous sinus (CS) and then into the cortical vein. The DAVF in case 1 was embolized completely via the OA to cast Onyx-18. Case 2 was a 69-year-old female who had red and swollen eyes. Angiography confirmed a DAVF of the proximal IPS, mainly supplied by the accessory meningeal artery (AMA), which drained into the CS and then into the ophthalmic vein, and the IPS was occluded. The DAVF in case 2 was embolized completely via the AMA to cast Onyx-18. After treatment, these two patients had uneventful recoveries. In our report, these two cases indicated that the DAVFs of the proximal and distal IPS shared different origins of feeding arteries. When the IPS is occluded, the transarterial approach via the main feeder, such as OA and AMA, can be feasible to cure the DAVF of the IPS.

Since the last IAEA-FEC in 2021, significant progress on the development of long pulse steady state scenario and its related key physics and technologies have been achieved, including the reproducible 403 s long-pulse steady-state H-mode plasma with pure radio frequency (RF) power heating. A thousand-second time scale (∼1056 s) fully non-inductive plasma with high injected energy up to 1.73 GJ has also been achieved. The EAST operational regime of high β _P has been significantly extended ( H _98y2 > 1.3, β _P ∼ 4.0, β _N ∼ 2.4 and n _e / n _GW ∼ 1.0) using RF and neutral beam injection (NBI). The full edge localized mode suppression using the n = 4 resonant magnetic perturbations has been achieved in ITER-like standard type-I ELMy H-mode plasmas with q _95 ≈ 3.1 on EAST, extrapolating favorably to the ITER baseline scenario. The sustained large ELM control and stable partial detachment have been achieved with Ne seeding. The underlying physics of plasma-beta effect for error field penetration, where toroidal effect dominates, is disclosed by comparing the results in cylindrical theory and MARS-Q simulation in EAST. Breakdown and plasma initiation at low toroidal electric fields (

For the typical multi-component periodic micro-Doppler signal parameter estimation, a helicopter rotor feature extraction method based on flicker phenomenon and phase compensation is proposed in this paper. The method firstly analyzes the formation mechanism of helicopter rotor flicker phenomenon in time domain and time-frequency domain through the integral model. Then the demodulation operator of the micro-Doppler signal is constructed for the phase compensation of the echoes with respect to the time-frequency flicker characteristics and the phase information of the slow time dimension of the target echoes. The parameter combination of the possible number of blades and rotational speed is predicted using the time domain flicker interval, and the phase compensation process is evaluated and optimized to significantly reduce the amount of computation. Finally, the parameter estimation of rotor blade number, blade length and rotational speed is acquired by calculating whether the center frequency of each flicker after phase compensation is periodically focused to zero frequency. The simulation results show that the method can effectively estimate the main parameters of helicopter rotor blades, and the processing results of the measured data show that the proposed method has more stable performance compared with OMP algorithm and Hough transform, which provides a new technical way for helicopter rotor blade feature extraction.

BackgroundAneurysms in moyamoya vessels or on collaterals are difficult to treat. Parent artery occlusion (PAO) via endovascular treatment (EVT) is often the last resort, but the safety and efficacy of this approach need to be evaluated.Materials and methodsA retrospective study was performed on patients admitted to our hospital who were diagnosed with unilateral or bilateral moyamoya disease (MMD) associated with ruptured aneurysms in moyamoya vessels or on collaterals. These aneurysms were treated with PAO, and the clinical outcome was recorded.ResultsEleven patients were aged 54.7 ± 10.4 years, and six patients were male (54.5%, 6/11). The aneurysms in 11 patients were single and ruptured, and the average size was 2.7 ± 0.6 mm. Three (27.3%, 3/11) aneurysms were located at the distal anterior choroidal artery, 3 (27.3%, 3/11) were at the distal lenticulostriate artery, 3 (27.3%, 3/11) were at the P2–3 segment of the posterior cerebral artery, 1 (9.1%, 1/11) was at the P4–5 segment of the posterior cerebral artery, and 1 was at the transdural location of the middle meningeal artery. Among the 11 aneurysms, PAO by coiling was performed on 7 (63.6%, 7/11), and Onyx casting was performed on 4 (36.4%, 4/11). Of 11 patients, 2 (18.2%, 2/11) suffered intraoperative hemorrhagic complications. During follow-up, all patients had good outcomes with a modified Rankin scale score of 0–2.ConclusionAs a last resort, the application of PAO with coiling or casting Onyx for ruptured aneurysms in moyamoya vessels or on collaterals may be safe with an acceptable clinical outcome. However, patients with MMD may not always achieve expected health outcomes, and PAO for the aneurysm can bring only temporary relief.

Cavernous sinus dural arteriovenous fistula (CS-DAVF) is an abnormal communication between the CS and dural arteries from the internal carotid artery and external carotid artery. CS-DAVFs are not uncommon. The preferred treatment for most CS-DAVFs is transvenous embolization (TVE), which can achieve a high cure rate with few complications. The trans-inferior petrous sinus (IPS) route from the internal jugular vein to the CS is the favorite and most direct route to perform TVE in the great majority of CS-DAVFs. However, when the trans-IPS route fails and if the facial vein (FV) is patent and dilated, transfemoral trans-FV-superior ophthalmic vein (SOV) embolization of the CS-DAVF can be attempted. However, the transfemoral trans-FV-SOV route to embolize CS-DAVFs is often challenging, and there is insufficient knowledge about it. Therefore, an updated review of the transfemoral trans-FV-SOV route to embolize CS-DAVFs is necessary, and this review includes our experience. The images in this review are from our institute without the dispute of copyright. Issues regarding the transfemoral trans-FV-SOV route to embolize CS-DAV were discussed, including the FV anatomy and variation, various TVE routes to access CS-DAVF, the procedure of the transfemoral trans-FV-SOV route to embolize CS-DAVF, difficulty, and solution of the transfemoral trans-FV-SOV route to embolize CS-DAVF, and complications and prognosis of transfemoral trans-FV-SOV to embolize CS-DAVF. By reviewing the transfemoral trans-FV-SOV route to embolize CS-DAVFs, we found that this route provides a valuable alternative to the other transvenous routes. A good prognosis can be obtained with the transfemoral trans-FV-SOV route to embolize CS-DAVFs in select cases.

Influenced by historical background, regional economic development, and the frequent occurrence of armed conflict, the human–earth relationship in the Central and Southern Peninsula, which is located in a “fragmented zone”, is characteristic of the region. The Indochina Peninsula has now become an area of interest for the study of spatial changes in production–living–ecological spaces (PLES). Taking the Indochina Peninsula as the study area, this paper explores the evolution of the spatiotemporal patterns of PLES and its driving mechanism in the Indochina Peninsula, from 2010 to 2020, based on a grid scale. Methods such as the land-use transition matrix, land-use dynamics index, and geographically and temporally weighted regression (GTWR) were used in our model, which will provide the basic data and reference for sustainable development planning across the Indochina Peninsula. Our results show that, from 2010 to 2020, ecological space dominated the PLES pattern on the Indochina Peninsula, but its area gradually decreased, accompanied by a sharp increase in the areas of productive and living spaces. The area of PLES interconversion on the Indochina Peninsula in 2010–2020 was 212,818.70 km2, and the intertransfer of production and ecological spaces was distributed in a networklike manner throughout the Indochina Peninsula, while the transfer of living space was distributed in a pointlike manner. The migration path of the center of gravity of PLES on the Indochina Peninsula demonstrated a significant directional difference, and the direction and extent of the standard deviation ellipse distribution of the ecological space was similar to that of the production space. The PLES’s pattern evolution was affected by the degree of multiple factors, with a significant spatial and temporal heterogeneity. The positive and negative feedback effects of the factors were distributed in different areas and in different transfer directions.

Background. Only a few reported studies have used computed tomography angiography (CTA) to image ruptured aneurysms at the junction of the internal carotid artery (ICA) and posterior communicating artery (PcomA) in the context of the adjacent arteries. Therefore, we performed such a study using a GE Workstation. Methods. The parameters of each aneurysm and its adjacent arteries were measured. Then, statistical assessments were performed to compare the parameters of the aneurysm side and the lesion-free (control) side. Results. Sixty-three patients were included in this study. The average age was 62.1±11.0 years, and the ratio of males to females was 0.8 : 1. The measurement results showed that the mean aneurysmal height was 5.2±2.3 mm, the mean width was 4.7±2.2 mm, and the mean neck width was 4.5±1.9 mm. On the aneurysm side, the intradural ICA diameter was 4.34±0.90 mm, and the diameter of the ICA at its termination was 3.55±0.72 mm. A fetal-type PcomA was found in 52.4% of aneurysms. The other measured parameters were also provided. Statistical results showed that the height of the aneurysm was larger than the width (P

A global navigation satellite system (GNSS)-based multistatic radar is explored for target localization and kinematic state estimation. Since any point on the earth can be illuminated by a minimum of four satellites of each GNSS constellation at any time, GNSS-based passive radars can be inherently considered multistatic radars. In this paper, a method for jointly estimating the target position and velocity by utilizing both the time delays and Doppler shifts has been proposed, and an analytical accuracy analysis is also provided. In the new method, the bistatic range and Doppler for each path are firstly estimated by the range-Doppler (RD) method, and then by using the bistatic ranges and Doppler shifts. The least squares method is applied to estimate the target position and velocity simultaneously. Compared with the precedent target localization and velocity estimation method, the proposed method achieves a better estimation result with simple procedures. Simulation results are provided to validate the effectiveness of the proposed method.

This paper presents a passive bistatic radar (PBR) configuration using a global navigation satellite system as an illuminator of opportunity for the rotor blade feature extraction of a helicopter. Aiming at the strong fixed clutter in the surveillance channel of the PBR, a novel iteration clutter elimination method-based singular-value decomposition approach is proposed. Instead of the range elimination method used in the classic extended cancellation algorithm, the proposed clutter elimination method distinguishes the clutter using the largest singular value and by remove this value. At the same time, the fuselage echo of the hovering helicopter can also be suppressed along with the ground clutter, then the rotor echo of this can be obtained. In the micro-motion feature extraction, the mathematic principle of the flash generation process in the time–frequency distribution (TFD) is derived first. Next, the phase compensation method is applied to achieve the time–frequency flash shift in the TFD. After this, the center frequencies of the standard flashes in the TFD are compared with the standard frequency dictionary. The mean l1 norm is utilized to estimate the feature parameters of the helicopter rotor. In the experiments, the scattering point model and the physical optics facet model demonstrate that the proposed method can obtain more accurate parameter estimation results than some classic algorithms.