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This paper addresses the trajectory tracking problem of the Jiaolong submersible, a deep manned submersible for exploring and utilizing deep ocean resources. We propose a hybrid control method based on dual closed-loop model predictive control. The outer-loop position controller, based on MPC, tracks the reference trajectory under the actual velocity constraints and provides a virtual desired velocity input for the inner-loop controller. The inner-loop velocity controller, based on explicit nonlinear MPC, introduces a nonlinear disturbance observer and uses the NDO estimates to design the ENMPC control law. The novelty of this method is that it designs an analytical control law that considers the actual velocity constraints. The NDO compensates for external disturbances and model uncertainties, enhancing the robustness of the submersible in complex deep ocean environments. Simulation results demonstrate that the proposed hybrid controller has better control performance. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the general errors-in-variables (EIV) model, allowing both the uncertain coefficient matrix and the dispersion matrix to be rank-deficient. We derive the weighted total least-squares (WTLS) solution in the general case and find that with the model consistency condition: (1) If the coefficient matrix is of full column rank, the parameter vector and the residual vector can be uniquely determined independently of the singularity of the dispersion matrix, which naturally extends the Neitzel/Schaffrin rank condition (NSC) in previous work. (2) In the rank-deficient case, the estimable functions and the residual vector can be uniquely determined. As a result, a unified approach for WTLS is provided by using generalized inverse matrices (g-inverses) as a principal tool. This method is unified because it fully considers the generality of the model setup, such as singularity of the dispersion matrix and multicollinearity of the coefficient matrix. It is flexible because it does not require to distinguish different cases before the adjustment. We analyze two examples, including the adjustment of the translation elimination model, where the centralized coordinates for the symmetric transformation are applied, and the unified adjustment, where the higher-dimensional transformation model is explicitly compatible with the lower-dimensional transformation problem. [ABSTRACT FROM AUTHOR]

Vascular aging influences hemodynamics, elevating risks for vascular diseases and dementia. We recently demonstrated that knockout (KO) of Dusp5 enhances cerebral and renal hemodynamics and cognitive function. This improvement correlates with elevated pPKC and pERK1/2 levels in the brain and kidneys. Additionally, we observed that Dusp5 KO modulates the passive mechanical properties of cerebral and renal arterioles, associated with increased myogenic tone at low pressure, enhanced distensibility, greater compliance, and reduced stiffness. The present study evaluates the structural and mechanical properties of the middle cerebral artery (MCA) in Dusp5 KO rats. We found that vascular smooth muscle cell layers and the collagen content in the MCA wall are comparable between Dusp5 KO and control rats. The internal elastic lamina in the MCA of Dusp5 KO rats exhibits increased thickness, higher autofluorescence intensity, smaller fenestrae areas, and fewer fenestrations. Despite an enhanced myogenic response and tone of the MCA in Dusp5 KO rats, other passive mechanical properties, such as wall thickness, cross-sectional area, wall-to-lumen ratio, distensibility, incremental elasticity, circumferential wall stress, and elastic modulus, do not significantly differ between strains. These findings suggest that while Dusp5 KO has a limited impact on altering the structural and mechanical properties of MCA, its primary role in ameliorating hemodynamics and cognitive functions is likely attributable to its enzymatic activity on cerebral arterioles. Further research is needed to elucidate the specific enzymatic mechanisms and explore potential clinical applications in the context of vascular aging. [ABSTRACT FROM AUTHOR]

The chopper control system which is synchronized by the White Rabbit timing network is designed and implemented to meet the requirements of the chopper of ion source for the High-Intensity Heavy Ion Accelerator Facility (HIAF). The hardware system consists of timing modulation controller, waveform acquisition, parameter setting, and remote control of the chopper power supply. The software includes low-level drivers and top-level applications which are based on Experimental Physics and Industrial Control System (EPICS). The combination of hardware and software completes the interaction of timing messages with the White Rabbit network, waveform acquisition, the setting of timing modulation parameters in several running modes, and remote control of the chopper power supply, etc. The test results show that the system can achieve timing modulation with a resolution of 8 ns and waveform acquisition of embedded EPICS IOC (input/output controller) at a 125 MHz sample rate. The design, implementation, and test of the chopper control system are described in this paper. [ABSTRACT FROM AUTHOR]

This article investigates a new fixed-time control scheme for a general class of nonlinear systems with high-order mismatched disturbances. An integral sliding mode surface is designed based on the estimations of the mismatched disturbances, which enables the control scheme to reject the mismatched disturbances. A continuous terminal sliding mode control law is then proposed, which guarantees that the convergence time is finite and independent of the initial conditions. Furthermore, the rigorous analysis for the fixed-time stability is presented with the bi-limit homogeneous property and Lyapunov theory. Finally, both the numerical simulations and the experimental tests are given to verify the superiority of the proposed fixed-time control scheme. The core of the proposed control scheme, which is developed with the nonsingular terminal sliding mode control (NTSMC) technique and fixed-time disturbance observer, ensures the fixed-time convergence and strong robustness to mismatched disturbances. The practical significance of the proposed control design is demonstrated by a real application to a crane system. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) exerts a tremendous socio-economic burden worldwide. Although reduced cerebral blood flow is an early and persistent symptom that precedes the loss of cognitive function in AD, the underlying molecular and cellular mechanisms remain unclear. The present study investigated whether capillary endothelial inward rectifier potassium 2 (Kir2.1) expression is reduced in TgF344-AD (AD) rats and contributes to neurovascular uncoupling and cognitive deficits in AD. Three- to fourteen-month-old AD rats expressing mutant human APP and PS1 and age-matched wild-type (WT) F344 rats were studied. AD rats exhibited higher amyloid beta (Aβ) expression in the brain as early as 3 months of age and amyloid plaques by 4 months of age. Functional hyperemic responses induced by whisker stimulation were impaired at 4 months of age, which were exacerbated in 6-month- and 14-month-old AD rats. The expression of Kir2.1 protein was significantly lower in the brains of 6-month-old AD versus WT rats, and Kir2.1 coverage was lower in the cerebral microvasculature of AD than in WT rats. Aβ1–42 reduced the Kir2.1 expression in cultured capillary endothelial cells. Cerebral parenchymal arterioles with attached capillaries exhibited a reduced vasodilator in response to 10 mM K+ applied to capillaries, and constricted less following administration of a Kir2.1 channel blocker, compared to WT vessels. These results indicate that capillary endothelial Kir2.1 expression is reduced and contributes to impaired functional hyperemia in AD rats at early ages, perhaps secondary to elevated Aβ expression. [ABSTRACT FROM AUTHOR]

Nowadays, with the development of the Internet of Things and information security technologies, lightweight block ciphers are gradually being widely used. As a side-channel attack method, algebraic fault analysis has received attention from experts and scholars since its introduction. The familiar nonlinear operation in lightweight block ciphers is the S-box substitution, and the performance index of the S-box directly determines the security strength of the cipher. To further improve the efficiency of algebraic fault analysis, this paper proposes a method to rewrite the algebraic equations of S-box substitution by decomposing the original cubic S-boxes into two quadratic S-boxes. The results show that this method is significantly effective compared to the original method in GIFT-64 and SKINNY-64, especially in the SKINNY-64 block cipher, where the average solving time is reduced by several hundred times in the best case with the same samples. At the same time, our best results show that s single-bit fault injection is enough to recover the master key of SKINNY-64. In addition, the PRESENT-64 block cipher is also studied in this paper, and the results show that the method can also improve efficiency significantly. When the location of the single-bit fault is unknown, using the S-box decomposition method for SKINNY-64 can also significantly improve the solving success rate, reduce the number of faults, and speed up the solving. [ABSTRACT FROM AUTHOR]

The widespread application of permeable pavements in urban stormwater management practices requires a quick and easy model to evaluate their hydrological function during different clogging stages. The Natural Resources Conservation Service-Curve Number (NRCS-CN) method has extensively used for predicting direct runoff from rainfall. However, the standard initial abstraction ratio (λ) value of 0.2 in the model is the most ambiguous assumption and requires considerable refinement for the accurate runoff prediction of permeable pavements affected by clogging. This study calibrated the λ values of permeable brick pavement (PBP) with different clogging degrees to obtain an appropriate model to predict the runoff of PBP affected by clogging. The results indicated that the NRCS-CN model with standard λ value of 0.2 indeed overestimated the runoff over PBP surface, particularly at the initial clogging stage. The λ values showed a significant positive correlation with the clogging degree of PBP, while no significant correlation with the rainfall intensity. A function defining the parameter of λ, related to the saturated infiltration rate of PBP was developed. The accuracy of runoff prediction over the clogged PBP surface was greatly improved using the modified NRCS-CN model with the refined λ values. The NSE value rose to 0.96, and the MAE and RMSE values reduced to 2.66 and 3.85, respectively. Furthermore, the curve number (CN) values for the clogged PBP based on the calibrated λ values were much more consistent with the actual clogging rule of PBP, exhibiting an increased span and ranging from 35 to 98. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a global healthcare crisis. The TgF344-AD rat is an AD model exhibiting age-dependent AD pathological hallmarks. We confirmed that AD rats developed cognitive deficits at 6 months without alteration of any other major biophysical parameters. We longitudinally characterized cerebral hemodynamics in AD rats at 3, 4, 6, and 14 months. The myogenic responses of the cerebral arteries and arterioles were impaired at 4 months of age in the AD rats. Consistent with the ex vivo results, the AD rat exhibited poor autoregulation of surface and deep cortical cerebral blood flow 2 months preceding cognitive decline. The dysfunction of cerebral hemodynamics in AD is exacerbated with age associated with reduced cerebral perfusion. Further, abolished cell contractility contributes to cerebral hemodynamics imbalance in AD. This may be attributed to enhanced ROS production, reduced mitochondrial respiration and ATP production, and disrupted actin cytoskeleton in cerebral vascular contractile cells. [ABSTRACT FROM AUTHOR]

Although the least-squares (LS) adjustment within the Gauss–Markoff model (GMM) and the model with condition equations as dual problem have been geometrically interpreted, no one merged the LS adjustment formulated by the Gauss–Helmert model (GHM) also into the common pattern. We formulate the GHM from the GMM based on a partial orthogonality between their respective coefficient matrices. Then, the LS adjustment within these three models is interpreted geometrically, which implies that the GHM is not the combined model but the intermediate model between the GMM and the model of conditional equations. Meanwhile, the case of a singular dispersion matrix is analyzed once more, but now in the most general way, where the restriction of the Neitzel–Schaffrin rank condition is relaxed. The findings of this part can be summarized as: (1) The LS solution is developed within the general GHM, which yields the unique best linear uniformly unbiased estimation if the parameter coefficient matrix is of full rank; (2) We demonstrated that Baarda’s S-transformation also holds with the most general model setup; (3) In the general case, we proved that the unique S -homBLUMBE (best homogeneously linear uniformly minimum bias estimation) can be achieved by S - 1 -norm minimization within the LS solution set; (4) The S -homBLE (best homogeneously linear estimation) type is analyzed for the GHM for the first time, and we find it can function as the intermediate algebraic connection between the LS and the S -homBLUMBE solution. [ABSTRACT FROM AUTHOR]

Although centralized coordinates are applied in geodetic coordinate transformations implicitly or explicitly, the centering strategy has not been comprehensively investigated from the theoretical perspective. In this contribution, we replace the existing universal transformation model with a more compact formulation, where the singular cofactor matrix caused by the model structure is successfully evaded. Furthermore, the developed partition representation of the solution that avoids the numerical difficulty of the non-partition model is more general than any previous partition representation. According to the empirical pre-processing, we further establish two models: the shifting model and the translation elimination model. The former allowing arbitrary shifts in the coordinates of the same kind presents the translational invariance, i.e., the shift can be independent of the original coordinates and the structure of the stochastic model, whereas the latter removes the translation parameters in the pre-adjustment phase by the partial orthogonality of the coefficient matrices, which centralizes the coordinates and changes the stochastic model simultaneously. Test computations with different weight structures show the validity of these strategies. [ABSTRACT FROM AUTHOR]

The spectra emitted by highly charged ions, which are abundant in laboratory plasma and stellar systems, cover a wide range of wavelengths from near-infrared to x-rays. Measurements on such spectral lines can provide plasma information such as the electron temperature, electron/ion density, chemical composition, and the evolution of these parameters. To simulate the x-ray emission from comets and other celestial bodies irradiated by solar wind ions in the laboratory, we established an experimental platform for x-ray measurements at Institute of Modern Physics, Chinese Academy of Sciences, and measured the x-ray emission spectra from a series of metal and silicate minerals bombarded by slow highly charged nitrogen and oxygen ions. In this paper, we describe the x-ray measurement platform in detail and report the x-ray emission caused by the interaction of 1.5–20 keV/q Oq+ (q = 3, 5, 6) and Nq+ (q = 3, 5) ions with nickel surface. It is discovered that the measured x-ray yield and production cross section increase rapidly as increasing the impact energy, but have no discernible dependence on the charge state of incident ions. The experimental results reveal that the incident ions have been neutralized and achieved charge state equilibration before the K-shell electron is ionized. When the incident energy is greater than 5 keV/q, the Binary Encounter Approximation calculations are consistent well with the experimental data, indicating that the K-shell ionization of incident ions is due to direct Coulomb excitation processes that occur below the target surface. However, the experimental ionization cross sections clearly deviate from the Binary Encounter Approximation calculations when the impact energy is less than 5 keV/q. The discrepancy at the low collision energy is discussed and explained based on a multi-electron excitation model. [ABSTRACT FROM AUTHOR]

The rapid development of high-throughput single-cell RNA sequencing technology offers a good opportunity to dissect cell heterogeneity of animals. A large number of organism-wide single-cell atlases have been constructed for vertebrates such as Homo sapiens, Macaca fascicularis, Mus musculus and Danio rerio. However, an intermediate taxon that links mammals to vertebrates of more ancient origin is still lacking. Here, we construct the first Xenopus cell landscape to date, including larval and adult organs. Common cell lineage-specific transcription factors have been identified in vertebrates, including fish, amphibians and mammals. The comparison of larval and adult erythrocytes identifies stage-specific hemoglobin subtypes, as well as a common type of cluster containing both larval and adult hemoglobin, mainly at NF59. In addition, cell lineages originating from all three layers exhibits both antigen processing and presentation during metamorphosis, indicating a common regulatory mechanism during metamorphosis. Overall, our study provides a large-scale resource for research on Xenopus metamorphosis and adult organs. Single-cell RNA sequencing technology offers a unique opportunity to dissect cell heterogeneity of animals. Here, the authors construct a Xenopus cell landscape including larval and adult organs to dissect cell heterogeneity of the amphibian. [ABSTRACT FROM AUTHOR]

From the first described AD case in 1901 to the current year 2022, understanding the pathogenesis of Alzheimer's disease (AD) and dementia has undergone a long and tortuous journey. Many mechanisms of AD etiology have been proposed and studied. However, current medications and FDA-approved treatments cannot cure AD and AD-related dementias (AD/ADRD). Recently, brain hypoperfusion associated with neurovascular dysfunction was recognized as one of the causal factors in the development of AD dementia. Arteriosclerotic changes were observed in the first AD case. A recent study reported that the functional hyperemic response to whisker stimulation was reduced in 9–12 months old atherosclerotic mice. Interestingly, they found that evoked hemodynamic responses were not altered in age-matched AD mice or AD mice with superimposed atherosclerosis using 2D-optical imaging spectroscopy in chronic studies. However, functional hyperemia was impaired in AD mice using the same approach in an acute study. It is essential to scrutinize the available data critically since different genetic backgrounds, ages, sexes of studied animal models, and different approaches used for the same function even structural examination may provide opposite information. We certainly are closer to truly understanding the pathogenesis of dementia. We expect positive results from using aducanumab (Aduhelm®) as the first FDA-approved anti-amyloid monoclonal antibody as a treatment for AD/ADRD. We hope to identify and develop new drugs targeting other potential contributing mechanisms such as the cerebral vascular pathways. [ABSTRACT FROM AUTHOR]

In this paper, K-shell X-ray spectra of nitrogen are measured by the interaction of Nq+ (q = 3, 5) ions with Al and Cu surfaces in the impact energy range of 25–100 keV. K-shell X-ray yields per incident ion and then ionization cross sections are deduced from the measured K-X-ray spectra. It is found that both the yields and cross sections increase quickly with increasing impact energy, but have no apparent dependence on the target material and the charge state of the incident ion. The experimental results reveal that the incident Nq+ (q = 3, 5) ions have been neutralized and achieved a charge-state equilibration before the K-shell electron is ionized. The experimental ionization cross sections are compared with those from the plane wave Born approximation (PWBA) and the classical binary encounter approximation (BEA) theory. The BEA calculations are better consistent with the experimental data than the PWBA. It means that the K-shell ionization of the incident Nq+ (q = 3, 5) ions is due to the direct Coulomb excitation processes that occurred below the target surface. K-shell ionization cross sections of Nq+ ions incident on an Al target. The theoretical calculations of BEA and PWBA models are also shown for comparison [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) is a common disease in the intensive care unit (ICU). AKI patients with nonrecovery of renal function have a markedly increased risk of death compared with patients with recovery. The current study aimed to explore and validate the utility of urinary cell cycle arrest biomarkers for predicting nonrecovery in patients who developed AKI after ICU admission. Methods: We prospectively and consecutively enrolled 379 critically ill patients who developed AKI after admission to the ICU, which were divided into a derivation cohort (194 AKI patients) and a validation cohort (185 AKI patients). The biomarkers of urinary tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) were detected at inclusion immediately after AKI diagnosis (day 0) and 24 h later (day 1). The optimal cut-off values of these biomarkers for predicting nonrecovery were estimated in the derivation cohort, and their predictive accuracy was assessed in the validation cohort. The primary endpoint was nonrecovery from AKI (within 7 days). Results: Of 379 patients, 159 (41.9%) patients failed to recover from AKI onset, with 79 in the derivation cohort and 80 in the validation cohort. Urinary [TIMP-2]*[IGFBP7] on day 0 showed a better prediction ability for nonrecovery than TIMP-2 and IGFBP7 alone, with an area under the reciever operating characteristic curve (AUC) of 0.751 [95% confidence interval (CI) 0.701–0.852, p < 0.001] and an optimal cut-off value of 1.05 ((ng/mL)2/1000). When [TIMP-2]*[IGFBP7] was combined with the clinical factors of AKI diagnosed by the urine output (UO) criteria, AKI stage 2–3 and nonrenal SOFA score for predicting nonrecovery, the AUC was significantly improved to 0.852 (95% CI 0.750–0.891, p < 0.001), which achieved a sensitivity and specificity of 88.8% (72.9, 98.7) and 92.6% (80.8, 100.0), respectively. However, urine [TIMP-2]*[IGFBP7], TIMP-2 alone, and IGFBP7 alone on day 1 performed poorly for predicting AKI recovery. Conclusion: Urinary [TIMP-2]*[IGFBP7] on day 0 showed a fair performance for predicting nonrecovery from AKI. The predictive accuracy can be improved when urinary [TIMP-2]*[IGFBP7] is combined with the clinical factors of AKI diagnosed by the UO criteria, AKI stage 2–3 and nonrenal SOFA score. [ABSTRACT FROM AUTHOR]

In recent years, high-throughput single-cell sequencing technology has shown promise in overcoming these limitations in cell-based HTS. Cells from each well were fixed separately and subjected to in-cell RT for cell labeling followed by single-cell transcriptional profiling using Microwell-seq 2.0. Our previous works of mouse cell atlas[7] and human cell landscape[8] showed that Microwell-seq 1.0 is a sensitive, robust, and cost-effective scRNA-seq technology with advantages of low batch effects and high cell-type compatibility. Combining in-cell RT and Microwell-seq 1.0, we established Microwell-seq 2.0 for cost-effective and high-throughput HTS with single-cell transcriptional profiling (Fig. [Extracted from the article]

Trust plays an important role in human society. However, how does trust evolve is a huge challenge. The trust game is a well-known paradigm to measure the evolution of trust in a population. Reward and punishment as the common types of incentives can be used to improve the trustworthiness. However, it remains unclear how reward and punishment actually influence the evolutionary dynamics of trust. Here, we introduce individual reward and punishment into the N-player trust game model in an infinite well-mixed population, where investors use a part of the returned fund to reward trustworthy trustees and meanwhile punish untrustworthy trustees. We then investigate the evolutionary dynamics of trust by means of replicator equations. We show that the introduction of reward and punishment can lead to the stable coexistence state of investors and trustworthy trustees, which indicates that the evolution of trust can be greatly promoted. We reveal that the attraction domain of the coexistence state becomes larger as investors increase the incentive strength from the returned fund for reward and punishment. In addition, we find that the increase of the reward coefficient can enlarge the attraction domain of the coexistence state, which implies that reward can better promote the evolution of trust than punishment. [ABSTRACT FROM AUTHOR]

Background: Head and neck squamous cell carcinoma (HNSCC) is characterised by a dismal prognosis; nonetheless, limited studies have unveiled the mechanisms underlying HNSCC relapse.Methods: Next-generation sequencing was performed to identify the somatic mutations in 188 matched samples, including primary tumours, tumour-adjacent tissues (TATs), pre- and post-operative plasma, saliva and peripheral blood lymphocytes (PBLs) from 27 patients. The evolutionary relationship between TATs and tumours were analysed. The dynamic changes of tumour- and TAT-specific mutations in liquid biopsies were monitored together with survival analysis.Results: Alterations were detected in 27 out of 27 and 19 out of 26 tumours and TATs, respectively. TP53 was the most prevalently mutated gene in TATs. Some TATs shared mutations with primary tumours, while some other TATs were evolutionarily unrelated to tumours. Notably, TP53 mutations in TATs are stringently associated with premalignant transformation and are indicative of worse survival (hazard ratio = 14.01). TAT-specific mutations were also detected in pre- and/or post-operative liquid biopsies and were indicative of disease relapse.Conclusions: TATs might undergo the processes of premalignant transformation, tumorigenesis and eventually relapse by either inheriting tumorigenic mutations from ancestral clones where the tumour originated or gaining private mutations independent of primary tumours. Detection of tumour- and/or TAT-specific genetic alterations in post-operative biopsies shows profound potential in prognostic use. [ABSTRACT FROM AUTHOR]

Deep learning-based recommender systems have gained much attention due to the advantage of encoding content-based information, such as user textual reviews and item descriptions, images, or videos, without the trouble of manually crafting feature vectors. However, those systems are trained from scratch with randomly initialized parameters, where the training process can take a long time to converge. With the most recent breakthroughs in Natural Language Processing using transfer learning, pre-trained transformer-based models now provide a better foundation for textual information encoding. This inspires us to propose a transformer-based recommender system using transfer learning. As the first core contribution in this work, we apply transfer learning to the system, by fine-tuning the pre-trained transformer models for information encoding. The experiment result shows that the proposed system outperforms several other deep learning-based recommender systems on multiple datasets. As the second core contribution, we propose a novel user vector encoding algorithm that assists all the models to achieve a better performance, when the user content information is not available. [ABSTRACT FROM AUTHOR]

The characteristics of colloids in urban road runoff with different traffic in Beijing, China, such as concentration, particle size, chemical property, and affinity for heavy metals were determined. The concentration of colloids was high, and an evident first flush effect was found in the runoff of road with heavy traffic. A large portion of colloids were distributed in the range of 1–10 μm. Traffic activity, rainfall intensity, and time of sample collection would not change the size distribution of colloids in the road runoff. The chemical property of colloids in the road runoff would be influenced by the soil erosion nearby green space, causing the content of organic colloids was high. The correlation coefficient between the concentration of colloids in colloidal fractions and the concentration of heavy metals (Cu, Zn, Cd, Pb, Fe, and Mn) in the road runoff with different traffic decreased with the same sequence from 0.02–0.2 μm, 0.2–0.45 μm, 0.45–1 μm, to 1–10 μm, suggesting that the heavy metals had stronger affinity for the colloids with small size. The concentration of Cu, Pb, and Zn exhibited significant correlations with the concentration of organic colloids in the road runoff. More aggregated spherical particles were found in the TEM image of the road runoff with heavy traffic. Zeta potentials and RMV data showed that the colloids with smaller size and the colloids in the road runoff with lighter traffic were much more stable. [ABSTRACT FROM AUTHOR]

Temporary plugging agent (TPA) is widely used in many fields of petroleum reservoir drilling and production, such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturing operations. The commonly used TPA mainly includes hard particles, fibers, gels, and composite systems. However, current particles have many limitations in applications, such as insufficient plugging strength and slow degradation rate. In this paper, a degradable pre-formed particle gel (DPPG) was developed. Experimental results show that the DPPG has an excellent static swelling effect and self-degradation performance. With a decrease in the concentration of total monomers or cross-linker, the swelling volume of the synthesized DPPG gradually increases. However, the entire self-degradation time gradually decreases. The increase in 2-acrylamide-2-methylpropanesulfonic acid (AMPS) in the DPPG composition can significantly increase its swelling ratio and shorten the self-degradation time. Moreover, DPPG has excellent high-temperature resistance (150 °C) and high-salinity resistance (200,000 mg/L NaCl). Core displacement results show that the DPPG has a perfect plugging effect in the porous media (the plugging pressure gradient was as high as 21.12 MPa), and the damage to the formation after degradation is incredibly minor. Therefore, the DPPG can be used as an up-and-coming TPA in oil fields. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is a leading risk factor for aging-related dementia; however, the underlying mechanisms are not well understood. The present study, utilizing a non-obese T2DN diabetic model, demonstrates that the myogenic response of the middle cerebral artery (MCA) and parenchymal arteriole (PA) and autoregulation of cerebral blood flow (CBF) in the surface and deep cortex were impaired at both young and old ages. The impaired CBF autoregulation was more severe in old than young DM rats, and in the deep than the surface cortex. The myogenic tone of the MCA was enhanced at perfusion pressure in the range of 40–100 mmHg in young DM rats but was reduced at 140–180 mmHg in old DM rats. No change of the myogenic tone of the PA was observed in young DM rats, whereas it was significantly reduced at 30–60 mmHg in old DM rats. Old DM rats had enhanced blood-brain barrier (BBB) leakage and neurodegeneration, reduced vascular density, tight junction, and pericyte coverage on cerebral capillaries in the CA3 region in the hippocampus. Additionally, DM rats displayed impaired functional hyperemia and spatial learning and short- and long-term memory at both young and old ages. Old DM rats had impaired non-spatial short-term memory. These results revealed that impaired CBF autoregulation and enhanced BBB leakage plays an essential role in the pathogenesis of age- and diabetes-related dementia. These findings will lay the foundations for the discovery of anti-diabetic therapies targeting restoring CBF autoregulation to prevent the onset and progression of dementia in elderly DM. [ABSTRACT FROM AUTHOR]

Uniform peanut-like Co3O4 was synthesized by a simple solvothermal method using ethylene glycol and dethylene glycol as solvents, and polyvinylpyrrolidone as surfactant. Scanning electron microscope (SEM) and transmission electron microscope (TEM) proved that the obtained Co3O4 product has uniform size, and each of the peanut-like Co3O4 was made up of ultra-small nanoparticles. In consideration of the special structure, peanut-like Co3O4 was used as an anode electrode for lithium-ion batteries (LIBs), and which displayed satisfied electrochemical performance with high specific capacity (about 810 mA h g−1), long cyclability (700 mA h g−1 after 70 cycles), and a good rate performance. [ABSTRACT FROM AUTHOR]

Sentiment analysis is recognized as one of the most important sub-areas in Natural Language Processing (NLP) research, where understanding implicit or explicit sentiments expressed in social media contents is valuable to customers, business owners, and other stakeholders. Researchers have recognized that the generic sentiments extracted from the textual contents are inadequate, thus, Aspect Based Sentiment Analysis (ABSA) was coined to capture aspect sentiments expressed toward specific review aspects. Existing ABSA methods not only treat the analytical problem as single-label classification that requires a fairly large amount of labelled data for model training purposes, but also underestimate the entity aspects that are independent of certain sentiments. In this study, we propose a transfer learning based approach tackling the aforementioned shortcomings of existing ABSA methods. Firstly, the proposed approach extends the ABSA methods with multi-label classification capabilities. Secondly, we propose an advanced sentiment analysis method, namely Aspect Enhanced Sentiment Analysis (AESA) to classify text into sentiment classes with consideration of the entity aspects. Thirdly, we extend two state-of-the-art transfer learning models as the analytical vehicles of multi-label ABSA and AESA tasks. We design an experiment that includes data from different domains to extensively evaluate the proposed approach. The empirical results undoubtedly exhibit that the proposed approach outperform all the baseline approaches. [ABSTRACT FROM AUTHOR]

Quantification of the uncertainty associated with stormwater models should be analyzed before using modelling results to make decisions on urban stormwater control and management programs. In this study, the InfoWorks Integrated Catchment Modelling (ICM) rainfall-runoff model was used to simulate hydrographs at the outfall of a catchment (drainage area 8.3 ha, with 95% pervious areas) in Shenzhen, China. The model was calibrated and validated for two rainfall events with Nash-Sutcliffe efficiency >0.81. The influence of rainfall, model parameters and routing methods on outflow hydrograph of the catchment was systematically studied. The influence of rainfall was analyzed using generated rainfall distributions with random errors and systematic errors (± 30% offsets). Random errors had less influence than systematic errors on peak flow and runoff volume, especially for two rainfall events with larger depths and longer durations. The Monte Carlo simulations using 500 parameter sets were used to verify the equifinality of the nine model parameters and determine the prediction uncertainty. Most of the monitored flows were within the uncertainty range. The influence of two routing methods from rainfall excess to hydrograph was studied. The InfoWorks ICM model incorporating double quasilinear reservoir routing was found to have a larger effect on the simulated hydrographs for rainfall events having larger depths and longer durations than using the U.S. EPA's Storm Water Management Model nonlinear reservoir routing method did. [ABSTRACT FROM AUTHOR]

Convolutional neural networks are widely adopted for solving problems in image classification. In this work, we aim to gain a better understanding of deep learning through exploring the miss-classified cases in facial and emotion recognitions. Particularly, we propose the backtracking algorithm in order to track down the activated pixels among the last layer of feature maps. We then are able to visualize the facial features that lead to the miss-classifications, by applying the feature tracking algorithm. A comparative analysis of the activated pixels reveals that for the facial recognition, the activations of the common pixels are decisive for the result of classification; for the emotion recognition, the activations of the unique pixels indeed determine the result of classification. [ABSTRACT FROM AUTHOR]

We derive orbit and clock errors for BeiDou satellites from March 1, 2013, to September 30, 2016 by comparing broadcast ephemerides with the precise ephemerides produced by Wuhan University. The broadcast ephemerides are pre-processed to filter out the 'data-logging' errors, and a robust estimation is subsequently implemented for removing the time-varying common timescale bias between the broadcast and precise clocks. To obtain the nominal SISEs (Signal-In-Space Errors), the SIS (Signal-In-Space) outliers are excluded according to the standard of SIS integrity. The long-term satellite clock behavior reveals that for GEO, IGSO and MEO satellites, each category of satellites has its inter-category clock consistency, and the clocks of MEO as well as the clocks of IGSO satellites have better inter-category consistency than that of GEO satellites. Between different categories, GEO satellite clocks have been more divergent from IGSO satellite clocks since May 2014. The larger orbit errors, resulting in approximately 1-2 m orbit-only UREs (User Range Errors), periodically occur for all satellites every half year when the satellites are in eclipse period. For the GEO and IGSO satellites, several larger orbit errors may be caused by the effect of satellite maneuvering, resulting in 2-3 m orbit-only UREs. Most satellite clocks have a nonzero mean, and all MEO satellite clocks have a positive mean of approximately 1.0 m, whereas the IGSO satellite clocks have a negative mean at the same level. For the GEO satellites, the various means indicate that the clocks are divergent from one to another. The clock standard deviation of 1 m is achieved by all satellites except for C03. Near-zero means are obtained in along-track, cross-track and radial errors for the IGSO and MEO satellites but not for the GEO satellites. The average RMSs (Root Mean Square) of approximately 0.8, 1.7 and 2.0 m are obtained for the orbit-only UREs, global-average UREs and worst-UREs, respectively, for the constellation as a whole. The RMSs of clock errors for GEO, IGSO and MEO are 1.8, 1.4 and 1.3 m, respectively. Due to a nearly-static observation geometry, the GEO satellites always have the worst SISE performance, and as a result, they degrade the overall SISE statistical characterization. The analysis of URE and broadcast URA (User Range Accuracy) indicates that the broadcast URA of 2.0 m throughout is slightly optimistic. The unchanging URA of 2.0 m may not be able to describe adequately the accuracy of UREs. Instead, the upper-bound URA of 2.4 m is recommended to users. The cross-correlation analysis results show that there is a significant positive correlation between along-track errors and radial errors, whereas radial errors are not evidently correlated to clock errors as they are with GPS. [ABSTRACT FROM AUTHOR]

We discuss the Bayesian inference based on the Errors-In-Variables (EIV) model. The proposed estimators are developed not only for the unknown parameters but also for the variance factor with or without prior information. The proposed Total Least-Squares (TLS) estimators of the unknown parameter are deemed as the quasi Least-Squares (LS) and quasi maximum a posterior (MAP) solution. In addition, the variance factor of the EIV model is proven to be always smaller than the variance factor of the traditional linear model. A numerical example demonstrates the performance of the proposed solutions. [ABSTRACT FROM AUTHOR]

It is well known that the errors-in-variables (EIV) model has been treated as a special case of the traditional geodetic model, the nonlinear Gauss-Helmert model (GHM), for more than a century. In this contribution, an adjustment of the EIV model with equality and inequality constraints is investigated based on the nonlinear GHM. In each iteration, the constrained EIV model is linearized to form a quadratic program. Furthermore, the precision description is investigated for the mixed constrained problem. The demonstrated results from the numerical examples show that this approach avoids the large computational expenses of the existing combinatorial solution that normally accompany the number of inequality constraints. [ABSTRACT FROM AUTHOR]

This paper presents a novel sliding mode control (SMC) strategy based on approximate feedback linearization and enhanced nonlinear disturbance observer for small-scale unmanned helicopters with high-order time-varying matched and mismatched disturbance. The novel SMC method is developed by designing a new sliding surface with the estimation of mismatched disturbance and its derivative. The proposed novel SMC method possesses following two appealing traits. First, it is robust with both matched disturbance and mismatched disturbance. Second, the chattering problem can be attenuated significantly. Moreover, the uniformly ultimately bounded stability of the closed-loop helicopter system is proved by theoretical analysis. Finally, the excellent tracking performance and robustness of the proposed flight control scheme are demonstrated by simulation results. [ABSTRACT FROM AUTHOR]

Cement bitumen emulsion asphalt (CBEA) is obtained by mixing bitumen emulsion, cement, aggregates and filler at ambient temperature. CBEA is thought to be a promising substitute for hot mix asphalt because of its low environmental impact and cost-effectiveness. Disadvantages of this material are the long time required to reach its full strength and the inadequate understanding of the hardening mechanisms. This study aims at accelerating the development of mechanical properties of CBEA by using rapid-hardening cements while at the same time gaining a deeper understanding of the role of cement in CBEA. With this purpose, cold mix asphalt mixtures with cationic and anionic emulsions and different types of cement (ordinary Portland, calcium sulfoaluminate and calcium aluminate cement) were studied by means of isothermal calorimetry, measurements of water evaporation and Marshall tests. The results indicate that both anionic and cationic bitumen emulsions may affect the initial hydration rates of the cements used but have no significant influence on their degree of hydration after a few days. The addition of calcium sulfoaluminate and calcium aluminate cement to CBEA leads to mechanical properties after 1-day curing similar to those obtained with Portland cement after 1-week curing. Cement hydration dominates the strength gain, especially for rapid-hardening cements, and the type of cement influences both the amount of bound water and the rate of water evaporation from the CBEA. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-022-31949-2, published online 25 July 2022 The original version of this Article contained an error in the punctuation of the last name of the fourth author, which incorrectly read ''. These authors contributed equally: Yuan Liao, Lifeng Ma, Qile Guo, Weigao E, Xing Fang, Lei Yang. The correct version contains no punctuation and states ''. [Extracted from the article]

The mathematical approximation of scanned data by continuous functions like quadratic forms is a common task for monitoring the deformations of artificial and natural objects in geodesy. We model the quadratic form by using a high power structured errors-in-variables homogeneous equation. In terms of Euler-Lagrange theorem, a total least squares algorithm is designed for iteratively adjusting the quadratic form model. This algorithm is proven as a universal formula for the quadratic form determination in 2D and 3D space, in contrast to the existing methods. Finally, we show the applicability of the algorithm in a deformation monitoring. [ABSTRACT FROM AUTHOR]

Although the analytical solutions for total least-squares with multiple linear and single quadratic constraints were developed quite recently in different geodetic publications, these methods are restricted in number and type of constraints, and currently their computational efficiency and applications are mostly unknown. In this contribution, it is shown how the weighted total least-squares (WTLS) problem with arbitrary applicable constraints can be solved based on a Newton type methodology. This iterative process with quadratic convergence is expanded upon to become a compact solution for the WTLS with or without constraints. This compact solution is then further interpreted as a universal formula for the symmetrical adjustment of the errors-in-variables model which represents affine, similarity and rigid transformations in two- and three-dimensional space. Furthermore, statistical analysis of the constrained WTLS including the first-order approximation of precision and the bias was investigated. In order to substantiate our proposed method's applicability, it was used to solve the affine, similarity and rigid transformation problem in two- and three-dimensional cases, where the structure of the coefficient matrix and multiple constraints were taken into account simultaneously. [ABSTRACT FROM AUTHOR]

Evidence is accumulating indicating that UVA (320–400 nm ultraviolet light) plays an important role in photo-carcinogenesis. UVA is thought to produce reactive oxygen species in irradiated cells through photo-activation of inherent photosensitizers, and was recently reported to cause DNA double-strand breaks (DSBs) in exposed cells. We have investigated the involvement of UVA in mutations and DNA damage in somatic cells using Drosophila melanogaster larvae. Using the Okazaki Large Spectrograph, we previously observed that longer wavelength UVA (＞330 nm) was more mutagenic in post-replication repair-deficient D. melanogaster (mei-41) than in the nucleotide excision repair-deficient strain (mei-9). LED-light has recently been developed as a high-dose-rate UVA source. LED-UVA light (365 nm) was also more mutagenic in mei-41 than in mei-9. The mei-41 gene was shown to be an orthologue of the human ATR gene, which is involved in the repair of DSBs through phosphorylation of histone H2AX. In order to estimate the extent to which oxidative damage contributes to mutation, we established a new D. melanogaster strain (urate-null mutant) that is sensitive to oxidative damage and has a marker to detect somatic cell mutations. When somatic cell mutations were examined using this strain, LED-UVA was mutagenic in the urate-null strain at doses that were non-mutagenic in the urate-positive strain. In an effort to investigate the generation of DSBs, we examined the presence of phosphorylated histone H2AvD (H2AX D. melanogaster homologue). At high doses of LED-UVA (＞800 kJ m−2), levels of phosphorylated H2AvD (γ-H2AvD) increased significantly in the urate-null strain. Moreover, the level of γ-H2AvD increased in the excision repair-deficient strain but not in the ATR-deficient strain following UVA-irradiation. These results supported the notion that the generation of γ-H2AvD was mediated by the function of the mei-41 gene. It was reported that ATR functions on DSB repair in D. melanogaster. Taken together, we propose a possible pathway for UVA-induced mutation, whereby DNA double-strand breaks resulting from oxidative stress might be responsible for UVA-induced mutation in somatic cells of D. melanogaster larvae. [ABSTRACT FROM AUTHOR]

In order to implement the original BKZ algorithm in parallel, we describe it in terms of parallelism and give its parallel implementation scheme. Then we analyze the efficiency of algorithm's parallel implementation and show that the speedup factor of BKZ algorithm in parallel is extremely low. Therefore we present a new parallel lattice reduction algorithm suitable for multiprocessor computer architecture. The new algorithm can obtain a BKZ reduced basis and the parallel speedup is effective. Also with the practical results, although the computational complexity increases compared with the original BKZ algorithm, we still indicate that the new algorithm performs well in parallel and the time cost in parallel is less. At the same time, we show that the length of the shortest vector is smaller. [ABSTRACT FROM AUTHOR]