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This paper discussed the size of 3 D-printed personalized titanium plates that can gain maximum stability of mandibular fracture and minimize stress shielding through finite element analysis. A 3 D virtual model of mandible with mandibular angle fracture was created from the CT data of patient. 3 D-printed personalized titanium plates varying in length and thickness were designed, and finite element analysis was performed under different loading conditions and fracture healing periods. After that, the stress distribution and deformation of the mandible with gonial fracture could be observed, and the stress shielding rate could be obtained. Finally, SPSS21.0 was used for statistical analysis. The results of finite element analysis indicated that as the thickness of titanium plates and the healing time decreased, the maximum displacement increased, under a certain condition in which the pore size, the width, the hole distance and the bridge spacing were 2.0 mm, 4.0 mm, 6.0 mm, 12.0 mm, respectively. What's more, in this condition, the thicker the titanium plate and the shorter the healing time were, the higher the stress shielding was at central occlusion. When the thickness of the personalized 3 D-printed titanium plate was 1.0 mm, the maximum displacement tended to be stable and the stress shielding was minimized. It can not only improve the bone stability after tension band fixation, but also minimize the stress shielding, which is expected to expand the indications of tension band fixation.

Unmanned-aerial-vehicle-based (UAV-based) ultrawideband and ultrawidebeam (UWB) synthetic aperture radar (SAR) is very sensitive to atmospheric turbulence and suffers from serious 2-D space-variant motion errors (SVMEs) caused by the ultrawide beam and frequency-dependent phase errors caused by the ultrawideband. This article proposes an autofocus approach for UAV-based UWB SAR data based on the quasi-polar grid fast factorized backprojection (FFBP) imaging framework, multiple subband local autofocus (MSBLA), and trajectory deviation estimation. First, based on an improved weighted phase gradient autofocus (WPGA) method for subband-division local images, MSBLA is introduced to solve the local motion error estimation problem with frequency-dependent phase errors. Then, trajectory deviation estimation based on the weighted least square (WLS) method is performed to solve the 2-D SVME problem. Finally, the subaperture trajectory deviations are fused into a full-aperture trajectory deviation by an improved fusion strategy based on piecewise weighting. This approach is applied to real data from a new UAV-based UWB SAR. The results of both simulation and real data experiments are presented and verify the effectiveness of the proposed approach.

Pure hydroxyapatite (HA) as bone graft substitute has excellent osteogenic activity, but it has lower fracture toughness and its biological activity is harmed by the addition of toughening phases, which limits its clinical application. To alleviate the contradiction, columnar β-Si3N4 as the toughening phase and La3+/Y3+ sintering aid as active ions are used in this study to prepare β-Si3N4/HA composite biomaterials. According to the results, hardness and toughness of 10 wt% β-Si3N4/HA composite prepared by cold press sintering at 1300 °C were 6.44 GPa and 1.69 MPa m1/2, respectively, being 110% and 140% higher than those of pure HA. Moreover, 10 wt% β-Si3N4/HA composite exhibited better protein adsorption capacity and obviously stimulated adhesion, proliferation, and osteogenic differentiation of osteoblast. In addition, it was found that sintering aid not only facilitated the improvement of mechanical properties, but also promoted the formation of 100–200 nm nanostripe structure, which was beneficial to cell adhesion. Determination of La3+concentration combined with biological experiments also proved that its concentration range from 4×10−8 M to 6 × 10−8M was beneficial to cell proliferation and osteogenic differentiation. In summary, β-Si3N4 and sintering aids were shown to improve mechanical properties of HA at maintaining the biological activity of the latter.

Climate is a potential driver of tree allometry. To explore the sensitivity of height-diameter allometry to climate change, we compiled height-diameter pairs of ponderosa pine (Pinus ponderosa) in ...

Repair of metabolic function in large bone defect remains a critical challenge, which largely depends on the osteogenic property of bone scaffold. Furthermore, microporous structure is one of the most critical factors that influence the osteogenic performance of bone scaffold. Therefore, it is an effective method to explore porous structures aiming at promoting osteogenesis. In this work, hydroxyapatite, the most abundant inorganic substance in bone tissue, was considered the research material. Furthermore, a natural loofah with high porosity and connectivity was selected as the bionic structure to reconstruct a porous bone scaffold based on 3D printing. Four types of loofah-like bone scaffolds were reconstructed and fabricated, and they all have an appropriate pore size and complex internal structure with a desirable porosity. According to the osteogenic ability analyses of micro-CT and histological morphometric, the BV/TV data of Type Ⅱ could reach 33%. The bone formation was found in pores and deep, rugged surfaces of scaffolds. The bionic bone scaffolds can promote in vivo osteogenesis, confirming the utility of our designed bionic scaffolds for bone regeneration.

International audience; CD2 is largely described to promote T cell activation when engaged by its ligands, CD48 in mice and CD58 in humans, that are present on antigen-presenting cells (APCs). However, both CD48 and CD58 are also expressed on T cells. By generating new knockout mouse strains lacking CD2 or CD48 in the C57BL/6 background, we determined that whereas CD2 was necessary on T cells for T cell activation, its ligand CD48 was not required on APCs. Rather, CD48 was also needed on T cells. One exception was during cytotoxicity, which required CD48 on T cells and APCs. Fluorescence resonance energy transfer (FRET) studies in nonimmune cells provided evidence that cis interactions between CD2 and CD48 existed within individual cells. CD2-CD48 interactions on T cells enabled more robust T cell receptor (TCR) signals, including protein tyrosine phosphorylation. Using T cells from a CD2 knock-in mouse in which a tag was inserted at the carboxyl terminus of CD2, mass spectrometry analyses revealed that the role of CD2 in T cell activation correlated with its ability to interact with components of the TCR complex and the protein tyrosine kinase Lck. CD2-CD58 provided a similar function in human T cells. Thus, our data imply that T cell–intrinsic cis interactions of CD2 with its ligands are required for TCR signaling and T cell activation. Interactions with ligands on APCs contribute during cytotoxicity.

Objective To explore the utility of deep brain stimulation (DBS) telemedicine in the management of patients with movement disorders from January 2019 to March 2020, covering the main period of the COVID‐19 outbreak in China. Materials and Methods We obtained data from 40 hospitals around China that employed DBS tele‐programming for their outpatients with Parkinson's disease or dystonia from January 2019 to March 2020. Data were obtained on the number and nature of patients' DBS health care service requests, reasons for their requests, the number of DBS telemedicine sessions subsequently completed, safety issues, and the patients' satisfaction with the DBS tele‐programing parameter adjustments made. Results There were 909 DBS tele‐programming health service requests (from 196 patients) completed during the study period. The results showed: 1) the number of DBS telemedicine sessions requested and the number of patients examined increased during the COVID‐19 outbreak in February and March 2020 when compared with the monthly numbers in 2019; 2) the most common reason for the patients' health service requests was poor symptom control; 3) the most common DBS tele‐programming adjustment made was voltage change; 4) overall, most (89%) DBS tele‐programming adjustment sessions were experienced by the patients as satisfactory; and 5) significant adverse events and unexpected treatment interruptions caused by connection failure or other hardware‐ or software‐related problems did not occur. Conclusions DBS telemedicine could have a unique role to play in maintaining the delivery of DBS treatment and medical care to outpatients with movement disorders during the COVID‐19 pandemic.

Geosynchronous synthetic aperture radar (GEO SAR)-related technologies are being mature, and the first GEO SAR satellite is expected to launch in the next ten years. Under this circumstance, some equivalent experiments should be conducted at the current stage to validate some key characteristics or parameters, which could significantly increase the success possibility of the GEO SAR project. To validate the feasibility of GEO SAR imaging with long integration time, which is the most important and fundamental characteristic of GEO SAR, the first helicopter platform-based equivalent GEO SAR experiment with long integration time was performed in Qianxi County of China on May 22, 2019. The integration time of it is 80 s, which is carefully designed to maintain the consistence between itself and the integration time of the GEO SAR. Furthermore, the azimuth signal-to-noise ratio gain with long synthetic aperture time is analyzed. Moreover, the 2-D space-variant motion error introduced by the complex helicopter trajectory and the performances of different imaging algorithms are analyzed to choose the proper imaging algorithms; to overcome the flaws and unclarities of existing algorithms, some improvements are proposed to obtain the well-focused SAR image. What is more, the equivalence of this experiment is also analyzed detailedly to demonstrate the effectiveness of this experiment. At last, the imaging result with synthetic aperture time of 100 s and the comparison between itself and the optic photograph validate the success of this equivalent experiment and the feasibility of GEO SAR imaging with long integration time.

Introduction Influenza causes significant morbidity and mortality annually in the United States (US) and people with chronic medical conditions are thought to be at higher risk for severe disease and death. Infection is a leading cause of death for patients with end-stage kidney disease (ESKD). We used a national-level inpatient database to study the trend of influenza hospitalizations and in-hospital mortality for patients without and with ESKD. Methods The National Inpatient Sample (NIS) 2010-2019 was used. A primary diagnosis of influenza was identified using ICD-9-CM (487.X, 488.X) and ICD-10-CM codes (J09.X, J10.X, J11.X). ESKD was identified using a validated algorithm identifying patients with a diagnosis of ESKD or procedure code for dialysis and excluding patients with a diagnosis of acute kidney injury. Other diagnoses and procedures were identified using validated algorithms based on ICD-9-CM, ICD-10-CM, and ICD-10-PCS codes. Discharge-level weights were used to estimate the total number of admissions in the NIS universe. Weighted multivariable logistic regression was performed to study the association between ESKD and in-hospital death. Results 131,942 admissions with a primary diagnosis of influenza with 4,647 admissions for ESKD patients among them were included in our analysis. Admissions varied by influenza season and ESKD patients accounted for 2.91% to 3.65% of all influenza admissions each season. 2,081 influenza patients (1.58%) died in the hospital and 115 patients with influenza and ESKD (2.47%) died in the hospital. Age-adjusted in-hospital mortality varied from season to season but was consistently higher in ESKD patients (2.25% vs 1.38%). ESKD was a risk factor for in-hospital death (OR 1.26, 95% CI 1.15-1.38) after adjusting for age, gender, primary payer, heart failure, chronic lung disease, obesity, drug abuse, immunocompromised status, bacterial pneumonia, the Charlson Comorbidity Index, and the influenza season. Conclusion ESKD patients accounted for a significant proportion of influenza hospitalizations in the US from 2010-11 to the 2018-19 influenza season. Among people hospitalized primarily for influenza, age-adjusted in-hospital mortality varied from season to season and was consistently higher in ESKD patients. For people hospitalized primarily for influenza, ESKD was an independent risk factor for in-hospital death.

With the continuous development of the economy and society, new media technologies have been widely used in every industry and all walks of life. New media technologies are also applied in the ideological politics education of the Chinese college students. Therefore, this article makes a brief analysis of college education in the context of the new media technology. New media technology is applied to the ideological politics education of college students, which not only places the emphasis on the importance of ideological politics in an intuitive manner towards the students, but also creates a good social atmosphere and innovates the ideological and moral education model.

Patient: Male, 36-year-old Final Diagnosis: Pheochromocytoma Symptoms: Chest discomfort • headache • shortness of breath • symptomatic tachyarrhythmia Medication: — Clinical Procedure: — Specialty: General and Internal Medicine Objective: Rare coexistence of disease or pathology Background: Pheochromocytoma is a rare catecholamine-secreting tumor arising from chromaffin cells of the adrenal medulla. Wolff-Parkinson-White (WPW) pattern is a rare congenital cardiac conduction disorder in which 1 or more accessory pathways connects the atria and ventricles, bypassing the atrioventricular (AV) node. Patients with this type of accessory pathway who also experience pre-excitation evoked arrhythmias have what is termed WPW syndrome. Here, we present a patient with a WPW pattern who underwent surgical resection of a pheochromocytoma, review considerations relating to the perioperative management, and briefly summarize the hormonal effects of pheochromocytoma in a patient with a WPW accessory pathway. Case Report: A man in his early 30’s with a history of hypertension developed shortness of breath with palpitations, was noted to have delta waves on electrocardiogram (ECG), and was given a diagnosis of WPW syndrome. Six years later, he developed headache, chest pain, and flank discomfort in addition to his daily palpitations and shortness of breath. Plasma catecholamine levels were measured and found to be elevated, and imaging studies noted the presence of a large right-sided adrenal mass, consistent with a pheochromocytoma. A decision was made to proceed with a laparoscopic right adrenalectomy, which was successful and uneventful. Through the 30-day postoperative period, he reported no further episodes of symptomatic palpitations for the first time in several years. Conclusions: To the best of our knowledge, this is only the fourth case in the literature describing pheochromocytoma with co-existing WPW syndrome. In our case, resection of the pheochromocytoma ameliorated the patient’s chronic WPW-related tachyarrhythmia.

The average cross-correlation coefficient (ACCC) is a traditional Doppler centroid estimation (DCE) method applied for complex radar data. Though the ACCC method is accurate enough for movi...

Software-Defined Networking (SDN) has greatly boosted the productivity of data center networking and cloud computing. It introduces a central controller to take over most functions that otherwise reside in distributed forwarding devices. Such a centralized design, however, tends to make the control channel a bottleneck due to bandwidth fatigue. Only when this bottleneck is addressed can SDN greater benefit networking and computing infrastructures. Existing work saves control channel bandwidth at the expense of losing flow visibility. This paper designs and implements FastLane, a framework for bandwidth-efficient yet throughput-boosting SDN flow setup without sacrificing global flow visibility. FastLane informs only one on-path switch of a flow’s forwarding path while switches themselves cooperate to complete flow setup. FastLane thus keeps minimum traffic for flow setup in the control channel and leaves the rest to the data plane. We optimize the switch selection toward minimizing flow setup latency. To leverage the saved bandwidth for setting up more flows and therefore achieving higher throughput, we propose delegating certain flow setups from ingress to en-route switches. We prototype FastLane by modifying FloodLight controller and Open vSwitch. The results demonstrate FastLane’s benefits to higher SDN throughput with limited switching fabric overhead.

Introduction: DBS is a widely used therapy for PD. There is now a choice between fixed-life implantable pulse generators (IPGs) and rechargeable IPGs, each having advantages and disadvantages. This study aimed to evaluate the preference and satisfaction of Chinese patients with Parkinson's disease (PD) who were treated with deep brain stimulation (DBS).Materials and Methods: Two hundred and twenty PD patients were treated with DBS and completed a self-reported questionnaire to assess their long-term satisfaction and experience with the type of battery they had chosen and the key factors affecting these choices. The survey was performed online and double-checked for completeness and accuracy.Results: The median value of the postoperative duration was 18 months. The most popular way for patients to learn about DBS surgery was through media (79/220, 35.9%) including the Internet and television programs. In total, 87.3% of the DBS used rechargeable IPGs (r-IPG). The choice between rechargeable and non-rechargeable IPGs was significantly associated with affordability (χ(1)2 = 19.13, p < 0.001). Interestingly, the feature of remote programming significantly affected patients' choices between domestic and imported brands (χ(1)2 = 16.81, p < 0.001). 87.7% of the patients were satisfied with the stimulating effects as well as the implanted device itself. 40.6% of the patients with r-IPGs felt confident handling devices within 1 week after discharge. More than half of the patients checked their batteries every week. The mean interval for battery recharge was 4.3 days. 57.8% of the patients spent around 1 h recharging, and 71.4% of them recharged the battery independently.Conclusions: Most patients were satisfied with their choice of IPGs. The patients' economic status and the remote programming function of the device were the two most critical factors in their decision. The skill of recharging the IPG was easy to master for most patients.

To utilize the lignite residues after humic acid extraction, experimental studies on pyrolysis of Xianfeng lignite residue (XLR) were conducted with a fixed-bed reactor under nitrogen atmosphere in the temperature range of 500–900 °C. The product gas yield and composition, and the properties of solid product were investigated and compared with those obtained from pyrolysis of Xianfeng lignite (XL). The results showed that the gas yield of dry-ash-free XLR was higher than that of XL and the content of CO in the product gas increased rapidly with increasing temperature. The surface area of the char from XLR pyrolysis increased as the pyrolysis temperature increased, which reached a high value of 612 m2/g at 900 °C compared to only 10 m2/g for the char obtained from XL pyrolysis. The porosity development in the former was due to the activation of carbon in the char matrix with Na-containing groups leading to the formation of micropores and mesopores in the solids, which could be potentially useful as adsorbents.

Dynamic multi-objective optimization problem is one of the most current popular research hotspots and faces great difficulties. In this work, based on the multiple objectives of structural optimization of the management space of forest ecosystems, a dynamic multi-objective optimization model of forest spatial structure is constructed by using the variation of forest growth with time. In order to make the model solve the problem more efficiently, an algorithm which focuses on solving multi-objective optimization problems is applied with a new environment detection mechanism. Compared with two multi-objective optimization algorithms PDMIOA and dDMSMOPSO, four test functions i.e., FDA1, FDA3, dMOP1, and dMOP2, are used. The results show that the proposed algorithm is superior to PDMIOA and dDMSMOPSO in convergence performance, distribution performance, and tracking performance. We have also applied the model to the natural secondary forest stand of the Longhushan Stateowned Forest Farm in South Dongting Lake, and analyzed the model output. The results show that after optimization, the forest structural indicators such as homogeneity index, mixed degree, competition index, health degree, spatial density index and open ratio, are obviously better than those without optimization. In addition, the forest structure is also greatly improved. The proposed dynamic multi-objective optimization model of forest spatial structure can provide both theoretical basis and technical support for intelligent forest management.

Malware has started grabbing its undeserved share long before the blossom of Android ecosystem. Injected with malware, malicious applications (apps) may threat users in various ways like financial charges and information stealing. When the severity of a deluge of malware was first noticed, malware detectors delivered unsatisfactory detection accuracy, which further degenerated upon simple transformation of malicious apps. Now years later, we are eager to re-examine the robustness of malware detectors. A surprisingly disappointed finding is that even known malicious apps can evade quite a few detectors. We also find that repackaging with extracted exploitable code instead of readily available malware samples can evade more signature-based detectors. Furthermore, we find Android OS features of Service and Broadcast exploitable to enable malicious apps stealthily active on phones. We implement all these findings through DroidRide, a framework toward making Android malware less catchable to detectors and more active on phones. Our prototype based on two example apps—AndroRAT and MIUI Notes—demonstrates DroidRide's effectiveness in malware evasion. Toward defending against DroidRide alike evasion, we further suggest feasible design enhancements of malware detectors and Android OS.

The Alxa Plateau has one of the highest frequencies of dust events in China and one of the greatest contributions to East Asian dust. We compiled climate and dust storm data for the Alxa Plateau based on observational data from ten meteorological stations from 1960 to 2005. Our analysis showed that Guaizihu and Minqin dust centers had >26 days per year with dust storms versus 7–13 days for other desert and Gobi regions on the plateau. Variations in dust storm frequency during the study period showed that dust storms increased during the 1960s (until 1972), decreased until the late 1990s, and then increased slightly until 2002. About 75.6% of dust storms occurred in March, April, May, June, and July. Between 78.2 and 88.1% of the dust storms occurred during the daytime and 28.9% of the dust storms occurred between 13:00 and 16:00. The mean durations of dust storms in the Alxa Plateau ranged from 715 to 3,462 min. The annual number of minutes of dust storms averaged >1,800 min in the western Alxa Plateau. Dust storm frequency was inversely related to duration: the longer the average duration, the lower the frequency of such storms.