Search

The process of degrading unwanted or damaged mitochondria by autophagy, called mitophagy, is essential for mitochondrial quality control together with mitochondrial apoptosis. In mammalian cells, pan-Bcl-2 family members including conical Bcl-2 members and non-conical ones are involved in and govern the two processes. We have illustrated recently the BH3 receptor Hsp70 interacts with Bim to mediate both apoptosis and mitophagy. However, whether similar pathways exist in lower eukaryotes where conical Bcl-2 members are absent remained unclear. Here, a specific inhibitor of the Hsp70-Bim PPI, S1g-10 and its analogs were used as chemical tools to explore the role of yeast Bxi1/Ybh3 in regulating mitophagy and apoptosis. Using Om45-GFP processing assay, we illustrated that yeast Ybh3 mediates a ubiquitin-related mitophagy pathway in both yeast and mammalian cells through association with Hsp70, which is in the same manner with Bim. Moreover, by using Bax/Bak double knockout MEF cells, Ybh3 was identified to induce apoptosis through forming oligomerization to trigger mitochondrial outer membrane permeabilization (MOMP) like Bax. We not only illustrated a conserved ubiquitin-related mitophagy pathway in yeast but also revealed the multi-function of Ybh3 which combines the function of BH3-only protein and multi-domain Bax protein as one. [ABSTRACT FROM AUTHOR]

The South China Sea (SCS) displays remarkable responses and feedback to the summer monsoon intraseasonal oscillation (ISO). This study investigates how the SCS summer ocean circulation responds to the monsoon ISO based on weekly satellite data. In summer, the largest amplitudes for intraseasonal (30–90 days) sea surface height variations in the SCS occur around the northeastward offshore current off southeast Vietnam between a north–south eddy dipole. Our results show that such strong intraseasonal sea surface height variations are mainly caused by the alternate enhancement of the two eddies of the eddy dipole. Specifically, in response to the intraseasonal intensification of southwesterly winds, the northern cyclonic eddy of the eddy dipole strengthens within 1–2 weeks, and its southern boundary tends to be more southerly. Afterwards, as the wind-driven southern anticyclonic gyre spins up, the southern anticyclonic eddy gradually intensifies and expands its northern boundary northward, while the northern cyclonic eddy weakens and retreats northward. Besides the local wind forcing, westward propagations of the eastern boundary-originated sea surface height anomalies, which exhibit latitude-dependent features that are consistent with the linear Rossby wave theory, play an important role in ocean dynamical adjustments to the monsoon ISO, especially in the southern SCS. Case studies further confirm our findings and indicate that understanding this wind-driven process makes the ocean more predictable on short-term timescales. [ABSTRACT FROM AUTHOR]

The influences of sea surface wind on the oceanic mesoscale eddy are complex. By integrating our self-developed surface drifters with satellite observations, we examined the influence of sea surface wind on the distribution of water masses and biomass within the interior of an anticyclonic eddy. Ten drifters were deployed in the northern South China Sea in the spring of 2021. Eventually, six were trapped in an anticyclonic mesoscale eddy for an extended period. Interestingly, the drifters' trajectories were not symmetric around the eddy center, displaying a significant offset of the distance from the wind turns to the southerly wind. Particle tracking experiments demonstrated that this departure could mainly be attributed to wind-driven ageostrophic currents. This is due to the strength of wind-driven ageostrophic currents being more comparable to geostrophic currents when accompanied by a deflection between the directions of the wind-driven current and the eddy's translation. The drifters' derived data indicated that sub-mesoscale ageostrophic currents within the eddy contributed to this asymmetric trajectory, with Ekman and non-Ekman components playing a role. Furthermore, the evolution of ocean color data provided corroborating evidence of these dynamic processes, highlighting the importance of ageostrophic processes within mesoscale eddies. [ABSTRACT FROM AUTHOR]

Research on project scheduling optimization is trending toward many‐objective optimization, in which the number of objectives exceeds three. However, existing studies usually only consider the necessary logical constraints, ignoring descriptions of practical scenarios and corresponding complex constraints, which limit the designed algorithms in problems with such scenarios and constraints. This study focuses on the many‐objective repetitive project scheduling problem considering practical scenarios with complex constraints (MRPSP‐PSCC). Various constraints are described under flexible matching/mapping between multi‐crew, multi‐mode, and multi‐section scenarios. A many‐objective project scheduling model is proposed for synchronous optimization of time, cost, quality, resource usage, and interruption time. The multiphase balance of diversity and convergence nondominated sorting genetic algorithm III (B‐NSGA‐III) with unique advantages for continuous many‐objective optimization problems is transformed for discrete many‐objective optimization. A series of unique designs is employed in the algorithm, including three‐layer coding rules, constraint handling, and local search, to improve the problem‐solving efficiency of the algorithm. The effectiveness and superiority of the model and algorithm for MRPSP‐PSCC were verified through a case study. [ABSTRACT FROM AUTHOR]

Active rotor control of helicopters is the future development direction, and active flap control (AFC) is one of the most promising technologies. However, the numerical simulation of an AFC rotor is challenging. It is necessary to consider the fidelity of the local flow details while dealing with complex shapes and motions. Therefore, few simulations of the flow field and analyses of the influencing parameters have been conducted. In particular, there is a lack of aerodynamic design criteria and recommendations for the AFC rotor. Thus, a new overset assembly algorithm, an arbitrary multilevel moving grid transformation algorithm, and a solver for the unsteady Reynolds-averaged Navier-Stokes equations (URANS) are proposed to establish a suitable numerical method for AFC rotor simulation. The aerodynamic characteristics of the rotor and key influencing factors are systematically analyzed under different flow conditions and design and control parameters, and suggestions for the design of the AFC rotor are provided. The results show that the AFC significantly changes the load distribution of the rotor. The thrust loss of the rotor is approximately 1%, but the offset angle compensates for the loss. The control parameters show relatively consistent trends under different working conditions. The phase is the key control parameter, and the effect on the load is more pronounced when the control frequency is an integral multiple of the rotor's natural load frequency. Increasing the chord length, span length, and deflection amplitude can also enhance the active control performance. [ABSTRACT FROM AUTHOR]

The spatio-temporal pattern recognition of time series data is critical to developing intelligent transportation systems. Traffic flow data are time series that exhibit patterns of periodicity and volatility. A novel robust Fourier Graph Convolution Network model is proposed to learn these patterns effectively. The model includes a Fourier Embedding module and a stackable Spatial-Temporal ChebyNet layer. The development of the Fourier Embedding module is based on the analysis of Fourier series theory and can capture periodicity features. The Spatial-Temporal ChebyNet layer is designed to model traffic flow's volatility features for improving the system's robustness. The Fourier Embedding module represents a periodic function with a Fourier series that can find the optimal coefficient and optimal frequency parameters. The Spatial-Temporal ChebyNet layer consists of a Fine-grained Volatility Module and a Temporal Volatility Module. Experiments in terms of prediction accuracy using two open datasets show the proposed model outperforms the state-of-the-art methods significantly. [ABSTRACT FROM AUTHOR]

The modification mechanism of lanthanum on alumina inclusions in a nonoriented electrical steel at 1600 °C is investigated using laboratory experiments. Inclusions are analyzed using an automatic scanning electron microscope equipped with energy‐dispersive spectrum at 1, 5, 10, and 30 min after lanthanum treatment. The contents of total oxygen (TO), total sulfur (TS), and total lanthanum (TLa) in steel are analyzed. Results show that Al2O3 inclusions are modified by lanthanum in two ways. One is that the dissolved lanthanum directly reduces the aluminum in Al2O3 inclusions and forms LaAl11O18 or LaAlO3 ones. The other is that a new La2O2S or LaSx shell is preferentially generated at the outside of Al2O3 and forms multiphase inclusions. With time increasing, the La2O2S or LaSx shell gradually reacts with the Al2O3 core and generates stable lanthanum‐containing inclusions. At the initial stage of lanthanum treatment, many transient inclusions including LaSx, La2O2S, and La–P(–As) are formed due to the high concentration of lanthanum, while gradually redissolving with time increasing. With the increase in TLa content in steel, the formation sequence of stable inclusions is Al2O3 → LaAl11O18 → LaAlO3 → La2O2S → LaSx, which is consistent with thermodynamic analysis. [ABSTRACT FROM AUTHOR]

Fermented hollow dried noodles, new products emerging in China, are delicious, easy to digest and absorb. However, due to the porous structure produced by yeast, there are still some quality problems such as easy breakage during storage, splitting during cooking and poor textural and sensory quality that need to be addressed. The influence of polysaccharides (guar gum, sodium alginate, and sodium carboxymethylcellulose) on the rheological properties of dough, the microstructure and physicochemical properties, and the quality of fermented hollow dried noodles were studied. The addition of all polysaccharides with proper concentration can improve that quality of dough, dough sheets and noodles. Among which guar gum had the best effect. 0.3% guar gum significantly increased the flexibility (6.64 mm) and expansion index (196.49%) of test sample, significantly decreased the cooking loss (5.74%) and splitting rate (10.00%), and significantly increased the elasticity (0.87) and chewiness (3680.91), respectively. At the same time, the correlation between noodle quality and dough rheological properties was established. Results indicate that polysaccharides can significantly improve the quality of fermented hollow noodles by modified the rheological properties of dough, the microstructure and physicochemical properties of dried noodles. • Polysaccharides can strengthen the network structure of noodle dough. • Guar gum had the best effect in improving the quality of fermented hollow dried noodles among all polysaccharides. • The rheological properties of dough sheets were positively corelated to the quality of fermented hollow dried noodles. • 0.3% GG significantly improve the flexibility, expansion index, splitting rate, cooking and texture quality of noodles. [ABSTRACT FROM AUTHOR]

Two 5‐year (2010–2014) quasi‐global simulations using the Weather Research and Forecasting model coupled with Chemistry have been analyzed to quantify the impacts of atmospheric rivers (ARs) on aerosols in the western United States (U.S.). We find that AR days have reduced trans‐Pacific as well as U.S. aerosol mass because of enhanced rainfall and hence, wet removal of aerosols, compared to non‐AR days. ARs reduce trans‐Pacific aerosol mass through the cyclonic circulation that shifts the aerosol transport pathway southward and brings cleaner air from the north. However, ARs have larger impact on aerosols that originate over the U.S., which are concentrated closer to the surface compared to trans‐Pacific aerosols that are distributed more uniformly with altitude. While dust and sulfates dominate the mass for both trans‐Pacific and U.S. aerosols, ARs reduce dust composition fractions of trans‐Pacific aerosols but the AR impacts on composition fractions of U.S. aerosols are more variable. Plain Language Summary: Aerosols can be transported by strong westerlies across the North Pacific and reach North America all year around. These transported aerosol particles have been found to interact with the North Pacific atmospheric rivers (ARs). Generally, the aerosol particles from long‐range transport can influence ice nucleation in mid‐level orographic clouds and precipitation forming processes. On the other hand, trans‐Pacific transported aerosols may also be significantly influenced by the synoptic conditions during the AR days. However, the impacts of atmospheric rivers on trans‐Pacific aerosols over the western United States (U.S.) are not well understood. This study illustrates the aerosol distributions during the AR events and shows that ARs can reduce the trans‐Pacific and U.S. aerosols through the enhanced rainfall. Also, ARs can reduce trans‐Pacific aerosol mass through cyclonic circulation. Further, the impacts of ARs on the contribution of trans‐Pacific aerosol over the west coast of North America is positive, which is dominated by dust, followed by sulfate. However, the impacts of ARs on aerosol component fractions from the U.S. are more complicated. These results can give us some new insight into the impacts of ARs on the long‐range transported aerosols. Key Points: The impacts of atmospheric rivers (ARs) on aerosols in western United States (U.S.) are quantified using two 5‐year quasi‐global Weather Research and Forecasting model coupled with Chemistry simulationsARs reduce trans‐Pacific aerosols through precipitation and cyclonic circulation and have larger reduction on dust composition fractionsARs reduce U.S. aerosols because of the enhanced precipitation, but the impacts on composition fractions are more variable [ABSTRACT FROM AUTHOR]

Air pollution is a severe environmental problem in the Indian subcontinent. Largely caused by the rapid growth of the population, industrialization, and urbanization, air pollution can adversely affect human health and environment. To mitigate such adverse impacts, the Indian government launched the National Clean Air Programme (NCAP) in January 2019. Meanwhile, the unexpected city-lockdown due to the COVID-19 pandemic in March 2020 in India greatly reduced human activities and thus anthropogenic emissions of gaseous and aerosol pollutants. The NCAP and the lockdown could provide an ideal field experiment for quantifying the extent to which various levels of human activity reduction impact air quality in the Indian subcontinent. Here, we study the improvement in air quality due to COVID-19 and the NCAP in the India subcontinent by employing multiple satellite products and surface observations. Satellite data shows significant reductions in nitrogen dioxide (NO2) by 17% and aerosol optical depth (AOD) by 20% during the 2020 lockdown with reference to the mean levels between 2005–2019. No persistent reduction in NO2 nor AOD is detectable during the NCAP period (2019). Surface observations show consistent reductions in PM2.5 and NO2 during the 2020 lockdown in seven cities across the Indian subcontinent, except Mumbai in Central India. The increase in relative humidity and the decrease in the planetary boundary layer also play an important role in influencing air quality during the 2020 lockdown. With the decrease in aerosols during the lockdown, net radiation fluxes show positive anomalies at the surface and negative anomalies at the top of the atmosphere over most parts of the Indian subcontinent. The results of this study could provide valuable information for policymakers in South Asia to adjust the scientific measures proposed in the NCAP for efficient air pollution mitigation. [ABSTRACT FROM AUTHOR]

Blade-vortex interaction (BVI) noise is a significant source of rotor noise. In recent years, active flap control (AFC) has been used successfully to control BVI by adding a trailing edge flap to the blade. However, due to the rotor's complex shape and motion in AFC, the accurate simulation of the motion and unsteady flow field is challenging. Therefore, studies of noise control by AFC have mostly focused on experimental methods. Few numerical simulations were conducted on the noise reduction mechanism. In order to understand the noise reduction mechanism of the AFC clearly, this paper establishes a computational fluid dynamics (CFD) method based on an overset grid and tries to simulate the AFC airfoil flow field with the artificial vortex interaction. The noise characteristics are obtained from an acoustic analogy method based on the Farassat 1A (F1A) equation. By parameter analysis study and by testing the airfoil load and vertical interference distance, the results show that the proposed active control method exactly reduces the airfoil-vortex interaction noise. A maximum noise reduction of 1.56 dB is observed, and the most critical control parameter is the deflection phase of the trailing edge. When the vortex core passes over the airfoil, the load fluctuation and the interaction noise can be reduced by an upward deflection of the trailing edge. The flapping of the trailing edge significantly changes the vortex core's path, which can further control the downstream airfoil-vortex interaction and achieve noise reduction. [ABSTRACT FROM AUTHOR]

Searching for new high temperature superconductors has long been a key research issue. Fe-based superconductors attract researchers' attention due to their high transition temperature, strong irreversibility field, and excellent crystallographic symmetry. By using doping methods and dopant levels, different types of new Fe-based superconductors are synthesized. The transition temperature is a key indicator to measure whether new superconductors are high temperature superconductors. However, the condition for measuring transition temperature are strict, and the measurement process is dangerous. There is a strong relationship between the lattice parameters and the transition temperature of Fe-based superconductors. To avoid the difficulties in measuring transition temperature, in this paper, we adopt a machine learning method to build a model based on the lattice parameters to predict the transition temperature of Fe-based superconductors. The model results are in accordance with available transition temperatures, showing 91.181% accuracy. Therefore, we can use the proposed model to predict unknown transition temperatures of Fe-based superconductors. [ABSTRACT FROM AUTHOR]

Although possessing well‐defined nanostructures and excellent multi‐electron redox properties, polyoxometalate clusters have poor intrinsic electrical conductivity and are prone to aggregation due to large surface energy, which makes them difficult to be fully utilized when applying as electrode materials for lithium‐ion batteries. In this paper, monodisperse K7MnV13O38 (MnV13) clusters are achieved by rationally utilizing nano‐sized high conductive carbon dots (CDs) as stabilizers. Benefiting from the fully exposed redox sites of MnV13 clusters (high utilization rate) and sufficient interfaces with carbon dots (extra interfacial energy storage), the optimized MnV13/10CDs anode delivers a high discharge capacity up to 1348 mAh g−1 at a current density of 0.1 A g−1 and exhibits superb rate/cycling capabilities. Density functional theory (DFT) calculations verify that ionic archway channels are formed between MnV13 and CDs, eliminating the bandgap and greatly improving the electron/ion conductivity of MnV13 and CDs. This paper paves a brand‐new way for synthesis of monodisperse clusters and maximization of extra interfacial energy storage. [ABSTRACT FROM AUTHOR]

Resource scarcity, global climate change and environmental pollution are increasingly constraining the development of the automotive industry. China proposes to reach the carbon peak by 2030; to reach the carbon neutral double carbon target by 2060 and gradually promote a green and low-carbon transition in energy development. The development of new energy vehicles is an important approach for China to realize its energy structure transformation in the automobile industry. HEV, as a transitional product of automobile energy transformation, has the advantages of both internal combustion engine vehicles and electric vehicles, which can improve the fuel efficiency and the emission problem of internal combustion engine vehicles and the range is longer compared to electric vehicles. One of the important aspects of HEV research is the design of whole vehicle energy management strategy based on the model predictions. Particularly, model-based predictive control is one of the mainstream energy management strategies nowadays, and its optimization effect is mainly subject to the model prediction accuracy. In this study, we constructed the ITS environment of a local roadway through simulation, compared the speed prediction effects of different speed prediction methods in different prediction time domains, and fused the historical information of vehicles (speed of the vehicle in front, distance, signal status, distance, and remaining time). It is found that N-BEATS is more effective in predicting vehicle speed in different prediction time domains, and the prediction accuracy of the speed prediction model is effectively improved after its fusion of multivariate information. • Speed prediction based on real driving data. • Comparing the accuracy of different speed prediction methods in different prediction time domains. • Fusion of multivariate information (vehicle history, front vehicle speed, distance, signal light status, remaining time, and other factors) for speed prediction. [ABSTRACT FROM AUTHOR]

Circulating tumor cells (CTCs) have significant clinical value in early tumor detection, dynamic monitoring and immunotherapy. CTC detection stands out as a leading non-invasive approach for tumor diagnostics and therapeutics. However, the high heterogeneity of CTCs and the occurrence of epithelial-mesenchymal transition (EMT) during metastasis pose challenges to methods relying on EpCAM-positive enrichment. To address these limitations, a method based on negative enrichment of CTCs using specific leukocyte targets has been developed. In this study, aiming to overcome the low purity associated with immunomagnetic beads targeting solely the leukocyte common antigen CD45, we introduced CD66b-modified immunomagnetic beads. CD66b, a specific target for neutrophils with abundant residues, was chosen as a complementary approach. The process involved initial collection of nucleated cells from whole blood samples using density gradient centrifugation. Subsequently, magnetically labeled leukocytes were removed by magnetic field, enabling the capture of CTCs with higher sensitivity and purity while retaining their activity. Finally, we selected 20 clinical blood samples from patients with various cancers to validate the effectiveness of this strategy, providing a new generalized tool for the clinical detection of CTCs. [ABSTRACT FROM AUTHOR]

In order to provide a theoretical basis for the development of aftertreatment devices, this paper investigated the exhaust particles of petroleum diesel (B0) and waste cooking oil biodiesel (B100) using EEPS, XPS and TGA. The results showed that the particle number distributions of different particle sizes showed a bimodal distribution. With the increase of transport distance, the peak value of the nuclear mode particles decreases and of accumulation mode particles increases. With the increase of transport distance, the O/C ratio of the particles decreased, but the ratios of sp3/sp2, C–OH and C O content increased, i.e., the farther the transport distance was, the higher the degree of disordered graphitization structure was, and the surface oxygen-containing functional groups increase. The oxidation characteristic temperature decreased with the increase of transport distance, and the activation energy of exhaust particles decreased by more than 10%, i.e., the farther the transport distance, the higher the oxidation activity of the particles. Compared with B0, B100 particles have less PN, more disordered graphitized structure, more C–OH and C O content, and higher oxidation activity. The transport distance had similar effects on the size distribution, graphitized structure, surface functional groups and oxidation activity of B0 and B100 particles. • Distribution of particle number on the different particle size at different exhaust pipe positions. • Effect of transport distance on the graphitized structure of B0 and B100 particles. • The surface functional groups of B0 and B100 particles at different transport distance. • The influence of engine speed on the size distribution, graphitized structure and oxidation activity. • Comparison of the effect of transport distance on B0 and B100 particles. [ABSTRACT FROM AUTHOR]

• Accumulated VFAs exert reactive oxygen species stress(ROS) on indigenous microbiota. • Methanogens is less tolerant to ROS than bacteria. • Microbiome re-assembly demonstrated superior efficiency in recovering VFAs-stressed reactor. • Microbiome re-assembly reduced ROS stress. The accumulation of volatile fatty acids (VFAs) in anaerobic digestion (AD) systems resulting from food waste overload poses a risk of system collapse. However, limited understanding exists regarding the inhibitory mechanisms and effective strategies to address VFAs-induced stress. This study found that accumulated VFAs exert reactive oxygen species (ROS) stress on indigenous microbiota, particularly impacting methanogens due to their lower antioxidant capability compared to bacteria, which is supposed to be the primary reason for methanogenesis failure. To enhance the VFAs-stressed AD process, microbiome re-assembly using customized propionate-degrading consortia and bioaugmentation with concentrated digestate were implemented. Microbiome re-assembly demonstrated superior efficiency, yielding an average methane yield of 563.6±159.8 mL/L·d and reducing VFAs to undetectable levels for a minimum of 80 days. This strategy improved the abundance of Syntrophomonas, Syntrophobacter and Methanothrix , alleviating ROS stress. Conversely, microbial community in reactor with other strategy experienced an escalating intracellular damage, as indicated by the increase of ROS generation-related genes. This study fills knowledge gaps in stress-related metabolic mechanisms of anaerobic microbiomes exposed to VFAs and microbiome re-assembly to boost methanogenesis process. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Mineral dust aerosols can substantially influence the Earth's climate by altering the radiation budget and modifying cloud microphysical and radiative properties. Through long-range transport, dust aerosols could have a global impact. Here, using a fully coupled meteorology-chemistry model (WRF-Chem) and the tracer-tagging technique, we conduct quasi-global simulations to investigate the characteristics of dust intercontinental transport in the Northern Hemisphere and the source contributions to dust outflow from East Asia. Model results show that total dust emission from the main deserts (i.e., North Africa desert (NFD), Middle East desert (MED) and East Asia desert (EAD)) is about 4531 Tg yr−1, in which 66% is from NFD, 24% is from MED and 10% is from EAD. During long-range transport, the NFD and MED dust plumes are separated into two branches by the Tibetan Plateau, with higher dust concentration of 4 μg m−3 in the northern branch (37° N-60° N). The imported dust mass from NFD and MED to East Asia is 16.0 Tg yr−1 and 33.8 Tg yr−1, respectively; the local dust mass emitted from EAD can circumnavigate and import about 0.41 Tg yr−1 of dust into East Asia. As part of the "Asian outflow", the MED and NFD dust is transported above 600 hPa with concentration of 2 μg m−3, while the EAD dust is mainly transported below 600 hPa with concentration of 3 μg m−3. The total outflow dust mass from East Asia is 12.0, 9.7 and 7.7 Tg yr−1 from EAD, NFD and MED, respectively. Dust particles dominate the aerosol mass concentration with a fraction of 56.5% in southern East Asia and 75.4% in northern East Asia. Moreover, dust number from EAD dominates the total aerosol number north of 37oN below 600 hPa, with a size range of 0.156–0.625 μm, but the NFD dust number is mainly above 600 hPa. MED dust number dominates the total column aerosol number south of 37 oN, with a size range of 0.312–0.625 μm. Quantifying dust source contributions and the associated dust number loading and size distribution over East Asia is important for understanding the role of East Asian dust outflow in climate and hydrological cycle. Highlight • Investigating the intercontinental transport characteristics of dust from different sources. • Estimating the dust mass flux import into and outflow East Asia. • Quantifying the source contributions of dust outflow from East Asia. • Quantitatively describing dust number loading and size distribution over East Asia. [ABSTRACT FROM AUTHOR]

When the shipboard helicopter rotor engages and disengages on a ship deck, due to the influence of wind-over-deck environment and ship airwake, the heterogeneity of rotor airload is large. This large heterogeneity leads to the fluctuation of blade deflection which changes the aerodynamic forces and causes danger of over deflection. To investigate the aeroelasticity of a rotor blade and find the rule of deflection and the deformed blade aerodynamic force in the rotor/ship coupling flow field, we establish a loose computational fluid dynamics/computational structural dynamics (CFD/CSD) coupling model. This coupling model simulates the aeroelastic characteristics of the shipboard helicopter rotor during engagement and disengagement with ship motions. In the simulation, the CFD solver is based on Reynolds-averaged Navier-Stokes (RANS) equations and the CSD solver is based on the moderate deflection beam model. We compare the results with the experimental data and verify the effectiveness of the simulation. Through the analysis of the flow field, blade deflection, and aerodynamic forces under various wind-over-deck conditions at different positions, we find in certain cases, that the elastic deflection has a significant impaction the blade aerodynamic force. As the wind direction anglesincrease, the rotor blade is more likely to have a large negative elastic twist deflection, causing drop of aerodynamic forces and danger of over deflection. [ABSTRACT FROM AUTHOR]

Altitude has a significant effect on the combustion of diesel engines during cold start, especially during speed-up. In this study, combustion characteristics of speed-up period were investigated using an experimental test on a heavy-duty diesel engine with an intake and exhaust pressure controlled by the plateau simulation test system to simulate altitude conditions including 0 m, 3000 m and 4500 m. Further effects of altitude on ignition characteristics of diesel engine were accomplished through a zero-dimensional thermodynamic model coupled with a detailed kinetic model. Results indicated that as the altitude rose from 0 m to 3000 m, the pressure in the cylinder was reduced, the number of diesel engine speed-up cycles increased, and the rising speed ratio decreased during speed-up. There was a misfire after the fifth cycle at an altitude of 4500 m, and the rising speed ratio was significantly reduced. Through analysis of fuel injection, air intake and ignition phase, we confirmed that the misfire at the high 4500 m altitude was caused by the ignition delay, which was mainly controlled by chemical reaction during cold start. In the detailed kinetic study, the hot-flame and blue-flame reactions slowed down in the chemical reaction of the mixture as the altitude rose. The higher altitude enhanced the H-atom abstraction, but weakened the second O 2 addition and the peroxyalkylhydroperoxide isomerization. The decomposition reaction was enhanced. As a result, the overall reaction rate and the heat release fraction deteriorated, extending significantly the negative temperature coefficient (NTC) duration of the ignition. [ABSTRACT FROM AUTHOR]

Two radiation hardening processes for shallow trench isolation (STI), i.e., Si+ implantation and STI oxide nitridation are investigated, including the impact on nominal electrical characteristics and radiation hardness. The total ionizing dose effects of the nMOS devices are proved to be sensitive to the STI radiation hardening process conditions. There are optimum process conditions to achieve the best effectiveness of radiation hardening. Then, a 130-nm radiation-hardened PDSOI technology has been developed. The radiation hardness is verified by static random access memories with small storage capacities. [ABSTRACT FROM AUTHOR]

Human resource management (HRM) in healthcare is an important component in relation to the quality and efficiency of healthcare delivery. However, a comprehensive overview is lacking to assess and track the current status and trends of HRM research in healthcare. This study aims to describe the current situation and global trends in HRM research in healthcare as well as to indicate the frontiers and future directions of research. The research methodology is based on bibliometric mapping using scientific visualization software (VOSviewer). The data were collected from the Web of Science(WoS) core citation database. After applying the search criteria, we retrieved 833 publications, which have steadily increased over the last 30 years. In addition, 93 countries and regions have published relevant research. The United States and Australia have made significant contributions in this area. Current research articles focus on topics clustered into performance, hospital/COVID-19, job satisfaction, human resource management, occupational/mental health, and quality of care. The most frequently co-occurring keywords are human resource management, job satisfaction, nurses, hospitals, health services, quality of care, COVID-19, and nursing. There is limited research on compensation management and employee relations management, so the current HRM research field still has not been able to present a complete and systematic roadmap. We propose that our colleagues should consider focusing on these research gaps in the future. [ABSTRACT FROM AUTHOR]

The influences of silicon-rich shallow trench isolation (STI) on total ionizing dose (TID) hardening and gate oxide integrity (GOI) in a 130 nm partially depleted silicon-on-insulator (SOI) complementary metal-oxide semiconductor (CMOS) technology are investigated. Radiation-induced charges buildup in STI oxide can invert the parasitic sidewall channel of the n-channel transistor, which will increase the off-state leakage current and decrease the threshold voltage for the main transistor. Compared with the general STI process, the silicon-rich STI process can significantly suppress the increase in leakage current and negative shifts in subthreshold region induced by the total dose radiation, implying TID hardening for STI trench oxide. However, the silicon-rich STI process has a deleterious impact on GOI. It leads to the thin gate oxide thickness at trench corner and lowers the gate oxide breakdown voltage. Issues of gate oxide integrity induced by silicon-rich STI are investigated in this paper, and an optimized process to solve this problem is proposed and examined. Finally, the TID response of the optimized silicon-rich STI process is presented in comparison to the general and silicon-rich STI processes. [ABSTRACT FROM AUTHOR]

A new body tied to gate (BTG) n-channel metal-oxide-semiconductor field-effect-transistor (NMOSFET) with a diode in partially depleted SOI (PD SOI) is proposed and investigated. We first compare the transfer and output characteristics between the regular and BTG NMOSFETs with grounded body and floating body. The steep subthreshold slope (<6 mV/dec) and low OFF current (∼0.01 pA/μm) of the BTG NMOSFET with floating body are observed at V D = 3.3 V. Mechanisms of the floating body effect (FBE) and the diode are analyzed to explain the outstanding performance. The hysteresis characteristics of BTG NMOSFETs are also presented in comparison to regular ones. Finally, the steep subthreshold characteristics of the BTG NMOSFET with floating body at low drain voltage are studied for ultralow power application. [ABSTRACT FROM AUTHOR]

This paper proposes a new approach to optimally design LLC converters. The core of the proposed approach is an accurate algorithm that can find all the possible designs satisfying the peak gain requirement. Designers can conveniently evaluate several design results and find the optimal one for their respective applications. Part I of this paper proposes the accurate design algorithm, which is developed based on time-domain resonant waveforms, law of charge conservation, and conservation of energy. Design procedures are also provided for computer automation. [ABSTRACT FROM AUTHOR]

This paper proposes a new approach to optimally design LLC converters. The core of the proposed approach is an accurate algorithm that can find all the possible designs satisfying the peak-gain requirement. Designers can conveniently evaluate several design results and find the optimal one for their respective applications. Part II of this paper discusses design considerations and procedure using the proposed algorithm. Case studies reveal different design tradeoffs in different application scenarios. A 384-V nominal 300-V minimum input voltage range 12-V/50-A output LLC converter prototype with 97.3% peak efficiency is built to verify the proposed design algorithm. [ABSTRACT FROM AUTHOR]

A facile and efficient approach to access 1,2,4-triazolo[4,3- a]pyridines and related heterocycles has been accomplished through condensation of readily available aryl hydrazines with corresponding aldehydes followed by iodine-mediated oxidative cyclization. This transition-metal-free synthetic process is broadly applicable to a variety of aromatic, aliphatic, and α,β-unsaturated aldehydes, and can be conveniently conducted on the gram scale. [ABSTRACT FROM AUTHOR]

With the rapid development of advanced materials and manufacturing technologies, flow sensors have made significant progress in the field of mechanical engineering, which could cater to the development trend of the Internet of Things (IoT) and the ongoing Fourth Industrial Revolution. However, traditional power supply modes such as lithium batteries require regular recharging or replacement, which greatly causes too much inconvenience and maintenance consumption, and may also pose potential risks to the marine environment. The triboelectric nanogenerators (TENGs), based on the coupling effect of contact electrification and electrostatic induction, have been demonstrated to convert mechanical movements of the fluid into electrical signals with various features such as flexibility, conformability, and user‐friendliness. This review systematically summarizes for the first time the fundamental working mechanism, rational structural design, and analysis of practical application scenarios of triboelectric flow sensor as an emerging technology for flow monitoring of the Industrial IoT. According to the different fluid objects monitored, the latest representative achievements of triboelectric flow sensors can be divided into gas flow sensors, liquid flow sensors, and two‐phase flow sensors. Finally, the current challenges and future development directions of triboelectric flow sensors are examined, which can promote the further development of the field of the flow sensors. [ABSTRACT FROM AUTHOR]

• Both micro-sized inclusions and fine precipitates were statistically analyzed. • Proper La addition reduced inclusions, and enhanced grain size and texture factors. • The steel with 0.0006 wt% La possessed the best magnetic properties. • Excess rare earth sulfides deteriorated grain size and textures of steels. The effect of rare earth elements (REMs) on the magnetic properties of non-oriented electrical steels was studied using industrial trials. The variation of the magnetic properties was discussed in terms of the effect of inclusions, precipitates, grain size, and textures in the steel with and without REMs. Inclusions of MgO·Al 2 O 3 -CaS and (Mg, Mn, Ca)S in REMs-free steel were modified into composite ones of MgO·Al 2 O 3 -LaAlO 3 , La 2 O 2 S-MgO and (La, Ca)S in the steel with 0.0006% lanthanum, and to (La, Ce) 2 O 2 S-CaS-MgO, (Ce, La)S in the steel with 0.0007% lanthanum and 0.0015% cerium. The number density of fine MnS was remarkably decreased by the addition of REMs, leading to an increase in the average grain size. The steel containing 0.0006 wt% lanthanum possessed the best combination of core loss and magnetic induction due to the decrease of micro-sized inclusions and fine MnS, the increase of grain size, and the optimization of recrystallization textures. For the steel with excess REMs addition, the large number density of rare earth sulfides with the size of approximately 1 μm tended to deteriorate the grain size and textures. [ABSTRACT FROM AUTHOR]

• Morphology, nanostructure, functional group composition, and oxidation reaction of soot particles with different fuels are analyzed. • Soot particles from WCO biodiesel combustion exhibit more disordered nanostructure. • The surface functional group content and sp3/sp2 of biodiesel soot particles are higher. • Soot particles from WCO biodiesel is easier to be oxidized than fossil diesel soot particles. • The nanostructure definite correlations with soot particles reactivity. Biodiesel is one of carbon neutral fuels for diesel engine and waste cooking oil (WCO) would be the most viable source for biodiesel production in China. This paper studied the micromorphology, nanostructure, surface functional group composition, and oxidation activity characteristics of particles emitted from a China V bus fueled by pure WCO biodiesel and petroleum diesel, respectively. Compared with petroleum diesel, the results showed that particle mass (PM) and particle number (PN) of WCO biodiesel decreased by 38.66% and 38.12%, respectively, while the proportion of nucleation mode particles increased by about 10%. The soot particles of WCO biodiesel have higher disordered nanostructure, smaller primary particle size and fringe length, larger fringe separation distance and tortuosity, and lower graphitization degree than those of petroleum diesel. Moreover, the oxygen-containing surface functional groups content and carbon atom hybrid ratio of soot particles of WCO biodiesel were higher than those of petroleum diesel under the same oxidation temperature. And then the activation energy of soot particles from WCO biodiesel which contained more lattice defect structures was 38.43 kJ/mol, 37.8% lower than petroleum diesel, which is easier to be oxidized. [ABSTRACT FROM AUTHOR]

In vertebrates, neural crest cells (NCCs) are a multipotent embryonic population generating both neural/neuronal and mesenchymal derivatives, and thus the neural crest (NC) is often referred to as the fourth germ layer. NC development is a dynamic process, where NCCs possess substantial plasticity in transcriptional and epigenomic profiles. Recent technical advances in single-cell and low-input sequencing have empowered fine-resolution characterisation of NC development. In this review, we summarise the latest models underlying NC-plasticity acquirement and cell-fate restriction, outline the connections between NC plasticity and NC-derived cancer and envision the new opportunities in studying NC plasticity and its link to cancer. [ABSTRACT FROM AUTHOR]

We have developed a fluorescent peptide conjugate (TrpNDIRGDfK) based on the coupling of cyclo(RGDfK) to a new tryptophan-tagged amino acid naphthalenediimide (TrpNDI). Confocal fluorescence microscopy coupled with fluorescence lifetime imaging (FLIM) mapping, single and two-photon fluorescence excitation, lifetime components and corresponding decay profiles were used as parameters able to investigate qualitatively the cellular behavior regarding the molecular environment and biolocalisation of TrpNDI and TrpNDI–RGDfK in cancer cells. [ABSTRACT FROM AUTHOR]

The total ionizing dose (TID) effect of the pMOSFET from 130 nm partially-depleted silicon-on-insulator (PDSOI) is investigated. The data obtained from 60 Co γ-ray irradiation experiments indicate that input/output (I/O) device is more susceptible to TID effect than the core device. An anomalous off-state leakage increase is observed for I/O pMOSFET when drain is biased at a high voltage after irradiation. It is proved that this radiation-induced leakage relates to the enhanced gate-induce-drain-leakage (GIDL). Both the radiation-induced interface traps at the gate-oxide/body interface and the oxide trapped charges in the buried oxide (BOX) are responsible for the growth of the leakage current. These conclusions are also verified by the TCAD simulations. The isothermal annealing can recover the leakage current to the pre-irradiation level. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of ionizing radiation on floating body effects for the 130 nm PDSOI NMOSFETs. It is shown that the floating body effects are restrained by the irradiation both for the core device and the input/output (I/O) device. For the core device, the second peak of the front gate transconductance which is known as the gate-induced floating body effect degrades with the incremental total dose. The decline of the second g_m peak is ascribed to the impact of the radiation-induced leakage current, but not to the radiation-induced interface traps assisted recombination or the suppression of the electron valence band (EVB) tunneling. For the I/O device, the kink effect and the hysteresis effect in the output characteristic which are observed before irradiation become insignificant after irradiation. These phenomena are due to the fully depleted of the silicon film in the I/O device which is caused by the buried oxide charge trapping. In addition, a radiation-induced latch, which is result from the leakage current-induced impact ionization, is also observed in the I/O device. [ABSTRACT FROM PUBLISHER]

[Display omitted] • Particle size distribution of the China Ⅵ GDI engine under different working condition. • Effects of working condition on the oxidation activity of PM. • Oxidation activity of different diameter ultrafine particles. • The relationship between surface functional groups and oxidation activity of PM. Gasoline particulate filter (GPF) is one of the most important means to solve particle emissions of gasoline direct injection (GDI) engines in the present and the future. In order to provide a theoretical guidance for the regeneration control and improvement of GPF, this paper analyzes the oxidation activity and surface functional group of particulate matter (PM) emitted from a China VI GDI engine at different working conditions, and the oxidation characteristics of ultrafine particles. The results show that ultrafine particles account for most PM emitted from the GDI engine, and the ratio of ultrafine particulates is affected by working conditions. The activation energy of PM changes in the range of 110 ∼ 180 kJ/mol under different working conditions. With the increase of engine load, the oxidation activity of PM decreases, which is manifested by the increase in characteristic temperatures of the oxidation activity. As the increase of engine speed, the oxidation activity increases. The activation energy of ultrafine particles is in the range of 88.0 ∼ 111.4 kJ/mol, and its oxidation activity is not significantly related to the particle diameter. The content of C O and C–H functional groups change obviously under different working conditions. I C-H /I C=C and I C=O /I C=C are in the range of 1.14 ∼ 1.8 and 1.25 ∼ 2.17. The oxidation activity of PM is positively correlated with the content of C–H functional groups. [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluates the radiation responses of 3.3V I/O NMOSFETs from 130nm partially-depleted silicon-on-insulator (PDSOI) technology. The data obtained from 60Co ionizing radiation experiments indicate that charge trapped in the shallow trench isolation, particularly at the bottom region of the trench oxide, should be the dominant contributor to the off-state drain-to-source leakage current under ON bias. The body doping profile and device dimension are two key factors affecting the performance degradation of the PDSOI transistors after radiation. Significant front gate threshold voltage shift is observed in the T-shape gate device, which is well known as the Radiation Induced Narrow Channel Effect (RINCE). The charge trapped in the buried oxide can induce large threshold voltage shift in the front gate transistor through coupling effect in the low body doping device. The coupling effect is evaluated through three-dimensional simulation. A degradation of the carrier mobility which relates to shallow trench isolation (STI) oxide trapped charge in the narrow channel device is also discussed. [Copyright &y& Elsevier]

Highlights: [•] A hump effect in the back gate characteristic curve is reported. [•] Simple way to extract the sheet charge density along the STI sidewall is proposed. [•] The electric field distributions in the STI and BOX are simulated. [•] Charge trapped in STI is the main contributor to the off-state leakage. [ABSTRACT FROM AUTHOR]

The effects of the radiation-induced trapped charge in shallow trench isolation (STI) and buried oxide (BOX) on total ionizing radiation response of 0.13 \mum partially-depleted silicon-on-insulator (PDSOI) NMOS technology are analyzed respectively. The positive trapped charge in the STI oxide, but not in the BOX, is responsible for the off-state leakage increase after ON bias radiation. A new method is proposed to calculate the surface charge density along the STI sidewall. This method takes into account the influences of the non-uniform electric field and the variable oxide thickness in the STI region. Moreover, the calculated non-uniform charge density along the STI sidewall is verified by three dimensional simulations. Even though there is charge-accumulation in the BOX, it shows minimal impact on the front-gate characteristics of the PDSOI devices in this 0.13 \mum technology, except for the device with low body doping concentration. The positive charge trapped in BOX can induce significant threshold voltage shift in the RVT (regular Vth) I/O NMOSFET through coupling effect. [ABSTRACT FROM PUBLISHER]

Distributed air-gap inductors have the advantage of reducing winding loss in high switching frequency dc/dc converters. However, they also have the disadvantage of uneven distribution of flux density, which inevitably leads to uncompleted utilization of magnetic material. This paper proposes a horizontal-winding multipermeability low-temperature cofired ceramic (LTCC) inductor to increase inductance and improve efficiency without the necessity of increasing inductor volume. For the purpose of simplicity, a two-permeability LTCC inductor is taken as an example for analysis and comparison. Design of such an inductor is demonstrated with the aid of 2-D finite elementary analysis simulation. A two-permeability LTCC inductor together with a single-permeability LTCC inductor is fabricated for measuring and testing. The measured results show the two-permeability inductor has higher inductance than the single-permeability inductor. Both inductors are tested in a 5-V input, 3.3-V output dc/dc converter to test their performances. The testing results show the two-permeability LTCC inductor could further improve the efficiency of high-frequency dc/dc converters compared with the single-permeability LTCC inductor. [ABSTRACT FROM AUTHOR]

Distributed air-gap inductors such as iron powder chip inductors and low-temperature cofired ceramic (LTCC) inductors have the advantage of low-fringing effect loss. However, the flux density nonuniformly distributes in the magnetic cores, which results in the magnetic material closer to the conductor becoming saturated while the magnetic material further away from the conductor is still not fully utilized. This paper proposes a multipermeability distributed air-gap inductor structure to increase inductance without the necessity of increasing the inductor volume. The best discrete permeability value is investigated. Based on the best discrete permeability value, inductance as well as the inductance density trends is calculated by varying the number of permeability layers under the condition that thickness for each layer is constant. Also, the inductance variations versus the number of permeability layers are also obtained under the condition that the inductor thickness is constant. A three-permeability inductor and a single-permeability inductor are fabricated to evaluate the proposed method. The measured results show that the three-permeability inductor has a much higher inductance than the single-permeability inductor for the entire load range. Both inductors are tested in a 5-V input, 3-V output dc/dc converter to compare their performances. The results show that the three-permeability inductor can further improve the efficiency of high-frequency dc/dc converters. [ABSTRACT FROM AUTHOR]

In this paper, a novel control strategy is presented, which is capable of controlling a 12-V–1.5-V main buck converter and an auxiliary circuit to achieve significantly improved unloading response performance. While the charge balance controller minimizes the settling time of the main buck converter, the auxiliary circuit is controlled in boundary conduction mode (BCM) for a predictable pattern of auxiliary switching to reduce the output overshoot. Therefore, the reliability and dynamic performance of the entire system is significantly enhanced. Compared with existing technologies, the proposed BCM auxiliary switching strategy achieves improved output voltage overshoot and reduced auxiliary power losses at the same time. Furthermore, numerical analysis of the improved output voltage overshoot and reduced auxiliary power losses has been conducted for a design guideline. Finally, simulation and experimental results are provided to verify the proposed scheme on a 12-V–1.5-V 10-A buck converter prototype. [ABSTRACT FROM AUTHOR]

An experimental study on the emissions of a diesel car fueled with national II diesel fuel, Shanghai IV diesel fuel and mixed fuels B10, G10 and C10 is conducted, in which its modal emission characteristics of HC, CO, NOx and CO2 with I-type test cycle in GB 18352.3-2005 are analyzed. The results show that compared to national II diesel fuel, the engine fueled with Shanghai II diesel fuel, B10, C10 and G10 has lower emissions of HC, CO, NOx and CO2. With I-type test cycle in GB 18352. 3-2005, the major HC emissions are in urban driving cycles, while CO emissions in urban cold cycle and NOx and CO2 in suburban cycles. In acceleration phase, all HC, NOx and CO2 emissions increase. [ABSTRACT FROM AUTHOR]

Abstract: A new phenomenon, for the first time, shows that radiation-induced body effect factor decrease in NMOS transistors is presented. The results indicate that body effect factor shift decreases as the total ionizing dose (TID) level increases in NMOS transistors, especially in the narrow-channel ones, which can be considered as one of the radiation-induced narrow-channel effect (RINCE). A first-order model is developed by applying charge conservation principle. Good agreement is obtained by comparing the modeling with experimental results. Finally, some implications to mitigate the RINCE effect are discussed. [Copyright &y& Elsevier]

Abstract: The response of single flash cell in a 180-nm flash technology to total ionizing dose (TID) is studied. The results indicate that the erased cell flips at a dose level of 100krad(Si), whereas the programmed cell does not even at the dose level up to 1Mrad(Si). This asymmetric phenomenon is attributed to the difference between the reference current of the comparator circuit and the intrinsic current of the flash cell. For the first time, we show that the irradiation-induced flash cell drain-current variation does not saturate at the intrinsic value, i.e. the drain current of a device with neutrally charged floating gate. After degrading to the intrinsic state, the read current of the erased cell gradually increases while the programmed cell continues to increase and then slightly drops back. Radiation tolerance comparison of single flash cell, I/O transistors and high-voltage (HV) transistors demonstrates that HV NMOS is most susceptible to ionizing radiation. The radiation tolerance of the circuit level is also evaluated from the elementary devices. [Copyright &y& Elsevier]

Abstract: The effects of gamma ray irradiation on the shallow trench isolation (STI) leakage current in a 180nm technology are investigated. The radiation response is strongly influenced by the bias modes, gate bias during irradiation, substrate bias during irradiation and operating substrate bias after irradiation. We found that the worst case occurs under the ON bias condition for the ON, OFF and PASS bias mode. A positive gate bias during irradiation significantly enhances the STI leakage current, indicating the electric field influence on the charge buildup process during radiation. Also, a negative substrate bias during irradiation enhances the STI leakage current. However a negative operating substrate bias effectively suppresses the STI leakage current, and can be used to eliminate the leakage current produced by the charge trapped in the deep STI oxide. Appropriate substrate bias should be introduced to alleviate the total ionizing dose (TID) response, and lead to acceptable threshold voltage shift and subthreshold hump effect. Depending on the simulation results, we believe that the electric field distribution in the STI oxide is the key parameter influencing bias effects on the radiation response of transistor. [Copyright &y& Elsevier]

A first order model of radiation induced narrow-channel effect (RINCE) is developed by applying charge conservation principle to calculate threshold voltage shift due to total ionizing dose (TID) irradiation. The model provides a way for extracting effective sheet charge density along shallow trench isolation (STI) sidewalls. [ABSTRACT FROM AUTHOR]

Radiation enhanced drain induced barrier lowering (DIBL) effect under different bias conditions was experimentally observed and verified by 3D simulation for deep submicron MOSFETs with shallow trench isolation (STI) oxides. The off-state leakage current increased significantly after total ionizing dose (TID) above 200 krad(Si) for PASS ,OFF and ON bias condition. The irradiated devices exhibited enhanced DIBL effect, that is the off-state leakage current increases with drain voltage and DIBL parameter increases with TID. The oxide trapped charge in the STI sidewall enhances the DIBL by decreasing the drain to gate coupling, enhancing the electric field near the STI corner, and increasing the surface potential of lowly doped substrate along STI sidewall. A simple dipole theory describing the enhanced DIBL phenomenon is introduced. The phenomenon is a result of the electrostatic effect, which concentrates drain field on channel into the source along shallow trench isolation oxide. Effective non-uniform charge distribution is applied in the 3D simulation for the radiation enhanced DIBL effect. Good agreement between experiment and simulation results is demonstrated. [ABSTRACT FROM AUTHOR]

A reverse substrate bias is known to increase the threshold voltage and reduce the off-state leakage current, which is of great interest from a radiation perspective in space applications. In this work, substrate biases during both irradiation and post-irradiation test on the impacts of total ionizing dose effects in a 180 nm CMOS technology are studied. The results indicate that a negative substrate bias during irradiation impairs the radiation hardness while a negative substrate bias during post-irradiation test improves the radiation hardness for nMOS transistors. A simple model is proposed to discuss the net result including the both effects. We find that the substrate bias for radiation hardening does not always work in some special conditions, such as the device with very low body doping and the STI which is very sensitive to the electric field for the buildup of charge. [ABSTRACT FROM AUTHOR]

The effects of total ionizing on a 180-nm CMOS technology are comprehensively studied. Firstly, we show new results on the hump effect which has strong relationship to the STI corner oxide thickness. Secondly, the leakage current degradation in various devices after radiation is investigated. For the intra-device leakage, both body doping concentration and STI corner thickness play very important roles. For the inter-device leakage, due to the low electric field at the STI bottom, it is found to be insensitive to ionizing radiation. Thirdly, a method for extracting the effective threshold voltage of the sidewall parasitic transistor is proposed by studying the leakage output characteristics. Finally, we find that the drain saturation current increases in NMOS transistors after radiation, especially in the narrow-channel ones. [ABSTRACT FROM AUTHOR]