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Introduction: Environmentally friendly and efficient biochar precursor materials and their modification methods are of great significance in solving the problem of soil cadmium pollution. Materials and methods: This study prepared apple pomace biochar (ABC) from discharged apple pomace by pyrolysis at 500 °C. ABC was modified by phosphoric acid impregnation (P-ABC), MnO2 loading (Mn-ABC), and MnO2 loading after phosphoric acid impregnation (Mn-P-ABC). The biochar and modified biochar were described by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. The impacts of original and modified biochar on soil characteristics and the immobilization of original and modified biochar with different additions (4, 7, 10 and 13%) on Cd in contaminated soils were studied. Results and discussion: The outcomes show that ABC, P-ABC, Mn-ABC, and Mn-P-ABC are porous and amorphous materials rich in functional groups. All four types of biochar can enhance soil organic matter content, cation exchange capacity, and pH value, effectively improving soil properties. After application of biochar materials, the extractable Cd in soil was obviously reduced compared to the control, and 13% Mn-P-ABC reduced the extractable Cd in the soil by 43.84%. The results of Cd speciation analysis indicate that after the application of biochar materials, the acid soluble Cd in the soil reduced and the residual Cd increased. Conclusions: The treatment with 13% Mn-P-ABC resulted in a 35.57% decrease in acid soluble Cd in soil and a 30.18% increase in residual Cd, indicating the best immobilization effect on Cd. [ABSTRACT FROM AUTHOR]

High‐performance thin‐film transistors (TFTs) integrated circuits (ICs) have become increasingly necessary to meet the emerging demands such as healthcare, edge computing, and the Internet of Things, etc. This article aims to point out the potential development trends and bottlenecks of TFT ICs, enhancing their performance in terms of electronic performance, stability, consistency, CMOS design, and manufacturing capability. Basic device structures and overall metrics of TFT ICs are explored, as well as their superiority compared to silicon‐based ultrathin chips. Hydrogenated amorphous silicon, low‐temperature polycrystalline silicon, and amorphous oxide semiconductors are widely used in displays due to their ability to be deposited on large areas at low processing temperatures and low cost, and are validated in many prototypes for TFT ICs. Their conduction mechanisms, process flows, performance evaluation, and recent advances are comprehensively viewed. In addition, the potential of emerging low‐dimensional materials as next‐generation channel materials is discussed, along with their limitations and progress in this field. Finally, the major challenges in manufacturing high‐performance TFT ICs and future perspectives are summarized. [ABSTRACT FROM AUTHOR]

Two‐dimensional material‐based field‐effect transistors (2DM‐FETs) are playing a revolutionary role in electronic devices. However, before electronic design automation (EDA) for 2DM‐FETs can be achieved, it remains necessary to determine how to incorporate contact transports into model. Reported methods compromise between physical intelligibility and model compactness due to the heterojunction nature. To address this, quasi‐Fermi‐level phase space theory (QFLPS) is generalized to incorporate contact transports using the Landauer formula. It turns out that the Landauer‐QFLPS model effectively overcomes the issue of concern. The proposed new formula can describe 2DM‐FETs with Schottky or Ohmic contacts with superior accuracy and efficiency over previous methods, especially when describing non‐monotonic drain conductance characteristics. A three‐bit threshold inverter quantizer (TIQ) circuit is fabricated using ambipolar black phosphorus and it is demonstrated that the model accurately predicts circuit performance. The model could be very effective and valuable in the development of 2DM‐FET‐based integrated circuits. [ABSTRACT FROM AUTHOR]

To improve the ecological environment quality of industrial cities and protect the health of residents, we determined the priority control factors of heavy metal(loid)s (HMs) pollution and risk in the resuspended street dust (RSD) of Shijiazhuang, an emblematic heavy-industrial city in North China, according to the probabilistic risk assessment method. The results showed that the HMs studied in Shijiazhuang RSD exhibited different pollution levels, that is, Hg showed moderate-to-severe pollution and above; Zn showed moderate-and-above pollution; Co, Cu and Pb showed non-pollution to moderate pollution; while As, Cr, Mn and Ni showed no pollution. The overall contamination of HMs in the RSD presented moderate-to-above contamination levels in >94% of samples. Mercury exhibited considerable-to-very-high ecological risk. The synthetic ecological risks of the HMs were considerable-to-above. The comprehensive pollution and synthetic ecological risk of HMs in Shijiazhuang RSD were mainly caused by Hg. The carcinogenic risk of HMs in RSD to local inhabitants and their non-carcinogenic risk to children should not be ignored. Coal-related industrial sources are a priority source to control. Hg and As are priority HMs to control. We suggest that local governments should strengthen the management of coal-related industrial sources and As and Hg emissions. [ABSTRACT FROM AUTHOR]

With the development of virtual reality and augmented reality, the pixel sizes of displays are reaching the sub-micrometer regime. One of the main challenges is the short-channel effect of the thin-film transistors (TFTs) in the driving circuits. In this work, we report the short-channel effects of indium-gallium-zinc-oxide source–gated transistor (IGZO SGT). The simulation results show that when reducing the channel length down to 500 nm, the output impedance of the IGZO SGT is still high up to 4.13 $\times \,\,10^{{8}}\,\, \Omega \!\cdot \!\mu \text{m}$ at gate–source voltage (${V}_{\text {GS}}$) of 5 V and drain–source voltage (${V}_{\text {DS}}$) of 7 V, 437 times higher than that of a conventional IGZO TFT of the same dimension. It is found that the Schottky source contact in SGTs can effectively suppress the back-channel current as compared with TFTs. The threshold voltage of short-channel SGTs remains almost the same when applying different drain voltages in contrast to TFTs. When ${V}_{\text {DS}}$ changes from 5 to 7 V at ${V}_{\text {GS}} =5$ V, the drain current of the IGZO TFT increases 23.7%, while the drain current of the SGT only increases 0.8%. The experimental results of IGZO TFTs and SGTs with a channel length of 500 nm showed similar dependence on the drain voltage to the simulation results. Such insensitivity to short-channel effects makes SGTs a promising candidate as current driving transistors in high-pixel-density display circuits. [ABSTRACT FROM AUTHOR]

Background: Long non-coding RNAs (lncRNAs) have been certified to play vital biological functions in glioma and have received considerable attention in the recent literature. Nonetheless, the role of LINC01158 in glioma remains to be elucidated. Methods: qRT-PCR, western blot and GEPIA database were applied for reporting the expression of CENPK and LINC01158 in glioma and the correlation between LINC01158 and CENPK expression. EdU, colony formation, CCK-8, caspase-3 activity and TUNEL assays probed the impacts of LINC01158 on glioma cell growth. Subcellular fractionation and FISH assays revealed the cellular distribution of LINC01158. Luciferase reporter and RIP assays examined ceRNA network of LINC01158, CENPK and miR-6734-3p. Results: LINC01158 and CENPK were both overexpressed in glioma and a positive regulation of LINC01158 on CENPK was corroborated. LINC01158 served a pro-proliferative and anti-apoptotic part in glioma by sponging miR-6734-3p to augment CENPK. Conclusion: LINC01158 enhances CENPK by serving as sponge for miR-6734-3p to facilitate glioma development, proposing LINC01158 as a new player in glioma. [ABSTRACT FROM AUTHOR]

Bilateral basal ganglia hemorrhages are extremely rare and have very poor prognosis. We describe the case of a 52-year-old woman with a history of hypertension who experienced bilateral basal ganglia hemorrhages. We performed bilateral hematoma aspiration by minimally invasive surgery via frontal and temporal puncture points. We discuss the surgical procedure and review relevant literature pertaining to the underlying causes and complications of similar cases. [ABSTRACT FROM AUTHOR]

Objective: Biodegradable stents represent a new technological development in the field of cardiovascular angioplasty. The stent geometry plays a crucial role in determining stent performance. Methods: This study describes four stent models with various strut geometries (circular, triangular, hexagonal, and spline) and identical links. The performance of the various stents is assessed by modeling the processes of compression and balloon expansion using experimental and numerical techniques. Results: Four adjustable variables related to radial strength, foreshortening rate, maximum expanded diameter and coverage are considered in this studies. The maximum stress distributions from our numerical analysis are in agreement with the experimental fracture measurements. Conclusion: Analysis of the stent parameters indicates that the hexagonal geometry is a relatively good stent strut design. The results described in this paper will be useful in further optimization studies and for the development of stents with a higher radial strength and increased fracture resistance. [ABSTRACT FROM AUTHOR]

The article titled "Landauer-QFLPS Model for Mixed Schottky-Ohmic Contact Two-Dimensional Transistors" discusses the challenges faced in designing future 2D integrated circuits due to the contact effect experienced by electrons in two-dimensional material transistors. The authors propose a compact and useful drain-current formula, known as the Landauer-QFLPS formula, as a potential solution to this problem. This formula has the potential to become a unique basis for electronic design automation in 2D circuitry. The article is authored by a diverse group of researchers, highlighting the collaborative nature of scientific research. [Extracted from the article]

Objectives: Postoperative pancreatic fistula (POPF) is a major concern after pancreatoduodenectomy (PD). We recently designed a new anastomotic method to reduce the rate of pancreatic fistula: polytetrafluoroethylene suture buttress-reinforced pancreaticojejunostomy (PBRP).Methods: An animal model and a computer simulation were used to measure the maximum stress and tensile strength of the pancreas with and without the suture buttresses. Then, a randomized controlled trial (RCT) was performed to compare the outcome of PD between patients who underwent PBRP vs traditional pancreaticojejunostomy (TP).Results: The maximum load in the animal model was significantly higher with the suture buttresses than without (5.47 ± 1.67 N vs 3.72 ± 1.36 N, p < 0.01), and in the computer simulation, the peak stress was lower with the suture buttresses than without (54.86 vs 486.8 MPa). There were no significant differences between the two groups in the overall frequency of POPF, but the rate of clinically relevant POPF was significantly lower in the PBRP group (2.8 vs 22.8%, p = 0.028). The pancreaticojejunostomy time was significantly longer in the PBRP group (19.57 ± 3.31 vs 17.17 ± 4.83 min, p = 0.018), and the PBRP group showed a shorter drainage tube retention duration (10 vs 12 days, p = 0.006) and postoperative hospital stay (13 d vs 15 d, p = 0.031).Conclusions: PBRP is a feasible and reliable procedure for preventing clinically relevant POPF. Additional multi-institution randomized trials should be conducted to confirm these results. [ABSTRACT FROM AUTHOR]

Local hemodynamic environment is a determinant factor in drug delivery from a drug eluting stent (DES) to the target arterial tissue. By using a simplified model of a DES, we demonstrated that if a DES had a drug release mode of uniform rate the drug released from the stent will distribute non-uniformly along the stent due to the flowing blood, with a significantly higher drug concentration at the distal part of the stent than that at the proximal one. This may explain why a DES could retard neointimal formation and vascular remodeling in downstream coronary segments. To solve this problem, we thereafter optimized the drug release mode of the DES as an exponential function. The simulation results showed that the optimized drug release mode could lead to a fairly uniform drug concentration distribution along the stent. Therefore, the present study suggested that to achieve a more effective result, optimization of drug eluting strategy (drug release mode) for the DES would be essential. [ABSTRACT FROM AUTHOR]

Previous animal studies by using tail-suspended hindlimb-unloaded rat model have shown that simulated microgravity-induced vessel structural and functional remodeling may be anatomic region dependent. However, little care has been taken to assess the structural adaptation of the endothelial glycocalyx, the apical surface of the endothelium, the key mechanosensor mediating nitric oxide (NO) production, and the natural protective barrier of the vasculature. Therefore, the present study extended simulated microgravity-induced vessel remodeling to the endothelial glycocalyx level. The percents of bone mineral density (BMD) change from both control and tail-suspended (TS) rats were measured by micro-computed tomography (Micro-CT). Structural parameters such as the luminal diameter (D), the thickness of each layer, the ratio of intima to media (IMR), the cross-sectional areas of the intima (CSA) and media (CSA) of vessels from three different regions (the common carotid artery, abdominal aorta, and femoral artery) were assessed by hematoxylin and eosin staining. Dimensions of the glycocalyx above, below, and away from the endothelial cell nucleus were examined by fluorescein isothiocyanate-labeled wheat germ agglutinin (WGA-FITC) binding to the cryosection of vessels. Our results show that 3-week tail suspension of rats increases the thickness and CSA of the abdominal aortic endothelium by 23.7 and 21.1 %, respectively, thickens the media layer of the common carotid artery by 34.0 %, and increases the luminal diameter, the CSA of the intima and media of the femoral artery by 75.7, 93, and 61.2 %, respectively. Correspondingly, the dimension of the glycocalyx away from the common carotid arterial and the abdominal aortic endothelial cell nucleus from tail-suspended rats shows a 1.66- and 1.64-fold increase respectively, while it shows a 0.79-fold reduction on the top of the femoral endothelial cells. These results suggest that simulated microgravity induces vascular endothelial glycocalyx remodeling in a regional-dependent manner. The perturbation of the endothelial glycocalyx at the lower body artery may be the first event of vascular remodeling initiating endothelial dysfunction, contributing to postspaceflight orthostatic intolerance. [ABSTRACT FROM AUTHOR]

Despite the crucial role of nitric oxide (NO) in the homeostasis of the vasculature, little quantitative information exists concerning NO transport and distribution in medium and large-sized arteries where atherosclerosis and aneurysm occur and hemodynamics is complex. We hypothesized that local hemodynamics in arteries may govern NO transport and affect the distribution of NO in the arteries, hence playing an important role in the localization of vascular diseases. To substantiate this hypothesis, we presented a lumen/wall model of the human aorta based on its MRI images to simulate the production, transport and consumption of NO in the arterial lumen and within the aortic wall. The results demonstrated that the distribution of NO in the aorta was quite uneven with remarkably reduced NO bioavailability in regions of disturbed flow, and local hemodynamics could affect NO distribution mainly via flow dependent NO production rate of endothelium. In addition, erythrocytes in the blood could moderately modulate NO concentration in the aorta, especially at the endothelial surface. However, the reaction of NO within the wall could only slightly affect NO concentration on the luminal surface, but strongly reduce NO concentration within the aortic wall. A strong positive correlation was revealed between wall shear stress and NO concentration, which was affected by local hemodynamics and NO reaction rate. In conclusion, the distribution of NO in the aorta may be determined by local hemodynamics and modulated differently by NO scavengers in the lumen and within the wall. [ABSTRACT FROM AUTHOR]

To elucidate the difference between Newtonian and shear thinning non-Newtonian assumptions of blood in the analysis of DES drug delivery, we numerically simulated the local flow pattern and the concentration distribution of the drug at the lumen-tissue interface for a structurally simplified DES deployed in a curved segment of an artery under pulsatile blood flow conditions. The numerical results showed that when compared with the Newtonian model, the Carreau (shear thinning) model could lead to some differences in the luminal surface drug concentration in certain areas along the outer wall of the curved vessel. In most areas of the vessel, however, there were no significant differences between the 2 models. Particularly, no significant difference between the two models was found in terms of the area-averaged luminal surface drug concentration. Therefore, we believe that the shear thinning property of blood may play little roles in DES drug delivery. Nevertheless, before we draw the conclusion that Newtonian assumption of blood can be used to replace its non-Newtonian one for the numerical simulation of drug transport in the DES implanted coronary artery, other more complex mechanical properties of blood such as its thixotropic behavior should be tested. [ABSTRACT FROM AUTHOR]

Although multilayer stents (MSs) can be used to treat aneurysm effectively, for some aneurysms with branches attached, the hemodynamic mechanisms are still unclear. In this work, we modeled five cases that involve 1–4-layer stents implanted in aneurysms with side branches, and the numerical approach was used. Case 1 corresponds to an aneurysm without a stent, and cases 2–5 represent 1–4-layer stents being employed within aneurysms, respectively. The results showed that the velocity within the sac declined dramatically and the eddies' intensity weakened with increased number of stent layers, time-averaged wall shear stress (TAWSS), and nitric oxide production rate (TARNO) dropped linearly with increase in stent porosity, and oscillatory shear index (OSI) and relative residence time (RRT) increased evidently with MS intervention. Moreover, the MSs had a slight effect on the patency of the side branch; its flow rate was still above the normal case than without aneurysm. It can be concluded that MSs are helpful in promoting the growth of thrombus within the aneurysm through an isolated hemodynamic environment and keeping the branch unobstructed, but more clinical evidences are required. [ABSTRACT FROM AUTHOR]

Background: Blood flow condition may have influence upon the hydraulic conductivity of venous graft (Lp,vein) in an arterial bypass, then affecting the accumulation of low-density lipoproteins (LDLs) within the graft wall. To probe this possibility, we first measured in vitro the filtration rates of swine lateral saphenous vein segments under different flow rates, and the correlation of Lp,vein with wall shear stress (WSS) was then obtained.Results: The experimental results showed that when WSS was very low, Lp,vein would increase drastically with WSS from 1.16 ± 0.15 × 10-11 m/s Pa at 0 dyn/cm2 to 2.17 ± 0.20 × 10-11 m/s Pa at 0.7 dyn/cm2, then became constant of approximately 2.33 × 10-11 m/s Pa as the WSS increased further. Based on the experimental results, we assumed three different cases of Lp,vein and numerically simulated the LDLs transport in an arterial bypass model with venous graft. Case A: Lp,vein = 2.33 × 10-11 m/s Pa; Case B: Lp,vein = 1.16 × 10-11 m/s Pa (static condition with WSS of 0); Case C: Lp,vein was shear dependent. The simulation showed that the deposition/accumulation of LDLs within the venous graft wall in Case A was greatly enhanced when compared with that in Case B. However, the LDL accumulation in the graft wall was similar for Case A and Case C.Conclusions: Our study, therefore, indicates that when the venous graft was implanted as a bypass graft, the Lp,vein might remain nearly constant along its whole length except for very few areas where the value of WSS was extremely low (less than 0.7 dyn/cm2) and the effects of Lp,vein modulated by blood flow on LDL transport may be neglected. [ABSTRACT FROM AUTHOR]

Background: Abdominal aortic aneurysm (AAA) is a kind of dangerous aortic vascular disease, which is characterized by abdominal aorta partial enlargement. At present, endovascular aneurysm repair (EVAR) is one of the main treatments of abdominal aortic aneurysm. However for some patients after EVAR the aneurysm re-expanded and even ruptured, leading to poor postoperative effect. The stent-graft endoleak after EVAR was realized to influence the AAA in-sac pressure and contribute to the aneurysm re-enlargement.Methods: In order to analyze the influence of endoleaks positions on the pressure shielding ability of stent-graft after EVAR, type I and type III endoleak models were reconstructed based on computed tomography (CT) scan images, and the hemodynamic environment in AAA was numerically simulated.Results: When the endoleak was at the proximal position the pressure shielding ability will be obviously weakened. While, the pressure shielding ability was higher in the systole phase than that in diastole phase when the endoleak located at the middle or distal positions. Unfortunately, when the endoleak located at the proximal position, the pressure shielding ability would be relatively weak in the whole cardiac cycle.Conclusions: The results revealed that the influence of endoleaks on pressure shielding ability of stent-graft was both location and time specific. [ABSTRACT FROM AUTHOR]