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In this paper, an ultrasound beamforming method for plane wave (PW) imaging based on modified sidelobe blanking (MSLB) is proposed to improve image resolution and contrast ratio (CR). In this framework, PWs from various angles were designed to create main and auxiliary beamformer signals. Specifically, the PW signals from all angles were first coherently combined to serve as the main beamformer output signals. To prevent excessive clutter and noise, output signals in the main beamformer were weighted by the generalized coherence factor. Subsequently, the PW signals were split into positive and negative angles to perform a subtraction, creating the auxiliary beamformer. Finally, signals in the main beamformer were compared with the signals in the auxiliary beamformer point by point to further eliminate the noises and clutters. Compared with the delay and sum, full width at half maximum of the MSLB for point targets was reduced by an average of 54.17% and 51.65% in simulations and experiments, respectively; and the corresponding CR was improved by 55.38% and 18.40% on average. The MSLB method provided better imaging quality in human carotid arteries. In conclusion, the proposed method can effectively improve image resolution and CR with low computational complexity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Beamforming is vital for medical ultrasound imaging systems. The generalized sidelobe canceller (GSC) beamforming can improve the image quality of lateral resolution, but its performance improvement in contrast and robustness is limited. OBJECTIVE: This paper proposes an improved generalized sidelobe canceller algorithm based on multi-apodization with cross-correlation (MAXB-IGSC), which aims to improve the contrast and robustness of ultrasound imaging while maintaining the high image resolution and background speckle quality of GSC. METHODS: The proposed MAXB-IGSC uses multiple pairs of complementary received apodization functions to process the echo data individually to obtain multiple pairs of data sets. The average of their normalized cross-correlation coefficients is then calculated and utilized to determine the adaptive subarray length of the GSC covariance matrix and weights the output of the improved GSC. RESULTS: The MAXB-IGSC improves the contrast ratio (CR) by 171.18% in anechoic cyst simulation and by 91.23%/130.97%/171.76% in geabr_0 (a dataset from the University of Michigan) experiment compared with GSC, respectively. Furthermore, MAXB-IGSC exhibits significant noise immunity, which greatly improves the robustness of the imaging. The technology also maintains the brightness and uniformity of the background speckle. CONCLUSION: The proposed MAXB-IGSC has potential for obtaining high-quality ultrasound images in clinical applications. [ABSTRACT FROM AUTHOR]

Objective: to develop an integrative learning program for people with dementia. Method: a methodological study was conducted using Delphi technique to develop the learning program, followed by a feasibility test. An expert panel was invited to develop the integrative learning program based on the neuroplasticity and learning framework. A feasibility test was conducted to evaluate the implementation of the program in two centers after the training of personnel who run the program. Verbatim transcripts of case conferences were coded, analyzed, and collapsed into themes and sub-themes by consensus. Results: there was no indication for content modification during the period of program implementation. Qualitatively, the participating older adults showed improvement in communications, emotions, connectedness with self and others, and well-being. Conclusion: the integrative learning program was uneventfully implemented with promising results. The program is ready for full-scale research on its efficacy in multiple centers to obtain more robust evidence.

Background: Coronavirus disease 2019 (COVID-19) is frequntly accompanied by venous thromboembolism (VTE), and its mechanism may be related to the abnormal inflammation and immune status of COVID-19 patients. It has been proved that interleukin-6 (IL-6), ferritin and lactate dehydrogenase (LDH) may play an important role in the occurrence of VTE in COVID-19 infection. But whether they can server as predictors for VTE in COVID-19 is still unclear. In this study, we performed a systematic review and meta-analysis to compare IL-6, ferritin and LDH in VTE and non-VTE COVID-19 patients in order to shed light on the prevention and treatment of VTE. Methods: Related literatures were searched in PubMed, Embase, Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI), WANGFANG. COVID-19 patients were divided into VTE group and non-VTE group. Meta-analysis was then conducted to compare levels of IL-6, ferritin and LDH between the two groups. Results: We finally included and analyzed 17 literatures from January 2019 to October 2022. There was a total of 7,035 COVID-19 patients, with a weighted mean age of 60.01 years. Males accounted for 62.64% and 61.34% patients were in intensive care unit (ICU). Weighted mean difference (WMD) of IL-6, ferritin and LDH was 31.15 (95% CI: 9.82, 52.49), 257.02 (95% CI: 51.70, 462.33) and 41.79 (95% CI: -19.38, 102.96), respectively. The above results indicated that than compared with non-VTE group, VTE group had significantly higher levels of IL-6 and ferritin but similar LDH. Conclusion: This systematic review and meta-analysis pointed out that elevated levels of IL-6 and ferritin were significantly possitive associated with VTE, thus could be used as biological predictive indicators of VTE among COVID-19 patients. However, no association was found between level of LDH and VTE. Therefore, close monitoring of changes in IL-6 and ferritin concentrations is of great value in assisting clinicans to rapidly identify thrombotic complications among COVID-19 patients, hence facilitating the timely effective managment. Further studies are required in terms of the clinical role of cytokines in the occurrence of VTE among COVID-19 infection, with more reliable systematic controls and interventional trials. [ABSTRACT FROM AUTHOR]

Technology transfer is a conscious knowledge transfer and diffusion, which can promote the coordinated configuration and balanced development of technological innovation elements in geographical space. From the perspective of "space of flow", the technology transfer network is constructed. Utilizing patent technology transaction data from 2018, this study analyzes the agglomeration differentiation and spatial polarization patterns of technology transfer from network nodes, network layers, and network partition in Guangdong–Hong Kong–Macao Greater Bay Area. The conclusions are as follows: (1) The agglomeration of technology transfer is remarkable in the network, showing "two poles and two strong" as well as proximity advantages; Shenzhen and Guangzhou have become spatial poles within the network. (2) The Matthew effect is prominent and technology transfer at the spatial level is largely caused by core node interactions, while core‐edge hierarchical transmission mechanisms and geographical proximity contact characteristics are gradually developing. (3) Differences in roles between the plates are pronounced, and there is an agglomeration effect within a plate and between plates, as well as clear spillover effects. [ABSTRACT FROM AUTHOR]

Heat-assisted magnetic recording is a technology to improve recording density of hard disk drives. The authors' group previously proposed a device, in which a Au nano-antenna as a near-field transducer was attached to a GaAs ring resonator as a light source. The ring resonator should stably oscillate with a single mode to generate near-field light at the tip of the nano-antenna with sufficient energy density. A non-axisymmetric ring resonator structure was proposed this time to improve the energy density and laser oscillation stability. When the decenter between the inner and outer circles of the ring resonator increased, the resonance frequency increased and eigenmodes with higher radial mode order disappeared, which leads to stable laser oscillation. Moreover, when the decenter was 200 or 250 nm, the normalized energy density at the tip of nano-antenna increased 1.2–2.4 times compared with an axisymmetric ring resonator structure while keeping the quality factor to more than 5000. [ABSTRACT FROM AUTHOR]

Background: White matter hyperintensity (WMH) is a marker of age‐related cerebrovascular damage and is correlated with cognitive impairment; ischemia and inflammatory mechanisms have been proposed to be involved in its pathogenesis. These processes are associated with oxidative stress (OS), which may impair cellular function and affect antioxidant balance; however, the role of central antioxidant responses is still unclear. Method: Patients (age 55‐85) with ≥2 vascular risk factors or a previous vascular event were assessed at baseline for an exercise rehabilitation program. All participants completed the Montreal Cognitive Assessment (MoCA). Baseline WHM severity was determined using the standardized Canadian Dementia Imaging Protocol and semiautomatic protocols. Brain glutathione (GSH) at baseline was obtained in the anterior cingulate (AC) and occipital region (OC) using 1H magnetic resonance spectroscopy (MEscher–GArwood Point Resolved Spectroscopy). Spectroscopic analysis was completed using the Gannet toolkit (vers. 3.1) in Matlab (vers. 2020b). Result: Of 30 participants (mean age: 66.2 ± 7.42 SD; 80% male) currently enrolled, brain volumetric measurements were completed for 25 participants. Lower MoCA score was associated with greater total WMH volume, controlling for age (b[SE] = ‐0.017 [0.005], t(22) = ‐3.24, p = 0.004); this relationship remained significant when controlling for years of education separately (b[SE] = ‐0.016 [0.006], t(22) = ‐2.86, p = 0.01). Correcting for cerebrospinal fluid volume, lower AC‐GSH level was associated with higher deep WMH volume in the medial middle frontal (MMF) region of interest (b[SE] = ‐0.056 [0.023], t(23) = ‐2.38, p = 0.026), but not with MMF paraventricular WMH volume. After controlling for age, the model was no longer significant (F (2, 22) = 2.87, p = 0.078). No significant associations were found between OC‐GSH and occipital lobe WMH. Conclusion: As expected, total white matter hyperintensity volume was associated with poorer global cognition. In the medial middle frontal (MMF) region of interest, higher deep WMH was associated with lower GSH levels, suggesting altered brain antioxidant levels may be associated with the presence or formation of WMH. Recruitment is ongoing, and additional participants are needed to reinforce findings and to control for confounders in the analysis. [ABSTRACT FROM AUTHOR]

A highly efficient strategy was developed to fabricate a graphene oxide modified cellulose nanocrystal/PNIPAAm IPN (GO-CNC/PNIPAAm IPN) hydrogel, which was capable of effectively adsorbing cationic and anionic dyes. The adsorption of Congo red (CR) and methylene blue (MB) was investigated based on the effects of pH, adsorption isotherms, adsorption kinetics, and recycling experiments. The adsorption capacities for CR and MB of the GO-CNC/PNIPAAm IPN hydrogel adsorbent were 728.8 mg g−1 and 281.9 mg g−1, respectively, and the difference is due to complex electrostatic and chemisorption effects between the adsorbent and the dye, which could be explained using the Langmuir isotherm adsorption model and pseudo-second-order kinetics model. In addition, the GO-CNC/PNIPAAm IPN hydrogel could be used repeatedly, and the adsorption capacities for CR and MB were 84.9% and 82.4% of the original hydrogel after five re-adsorption experiments, respectively. This type of adsorbent provided the advantages of being low-cost, having simple preparation, being non-polluting, and having good adsorption effects and a long service life, which is promising for its use in dye wastewater treatment in the future. [ABSTRACT FROM AUTHOR]

We present weakly interacting massive particles (WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment (CDEX), based on the data from both CDEX-1B and CDEX-10 stages. In the nonrelativistic effective field theory approach, both time-integrated and annual modulation analyses were used to set new limits for the coupling of WIMP-nucleon effective operators at 90% confidence level (C.L.) and improve over the current bounds in the low mχregion. In the chiral effective field theory approach, data from CDEX-10 were used to set an upper limit on WIMP-pion coupling at 90% C.L. We for the first time extended the limit to the mχ < 6 GeV/c2 region. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) increases risk for vascular cognitive impairment-no dementia (VCIND), a precursor to dementia, potentially through persistent oxidative stress.Objective: This study assessed peripheral glutathione peroxidase activity (GPX), which is protective against oxidative stress, in VCIND versus cognitively normal CAD controls (CN). GPX activity was also evaluated as a biomarker of cognition, particularly verbal memory.Methods: 120 CAD patients with VCIND (1SD below norms on executive function or verbal memory (VM)) or without (CN) participated in exercise rehabilitation for 24 weeks. Neurocognitive and cardiopulmonary fitness (VO2peak) assessments and plasma were collected at baseline and 24-weeks.Results: GPX was higher in VCIND compared to CN (F1,119 = 3.996, p = 0.048). Higher GPX was associated with poorer baseline VM (β= -0.182, p = 0.048), and longitudinally with VM decline controlling for sex, body mass index, VO2peak, and education (b[SE] = -0.02[0.01], p = 0.004). Only CN participants showed improved VM performance with increased fitness (b[SE] = 1.30[0.15], p < 0.005).Conclusion: GPX was elevated in VCIND consistent with a compensatory response to persistent oxidative stress. Increased GPX predicted poorer cognitive outcomes (verbal memory) in VCIND patients despite improved fitness. [ABSTRACT FROM AUTHOR]

Accurate prediction of the trust relationship is the basis for trusted access and secure interaction between Internet of things nodes. To evaluate the degree of trust, a trust metric is assigned to every node depending on its several attributes. Normal nodes in Internet of things tend to suffer collusion attacks from malicious nodes; thus, the accuracy of the trust measurement decreases. To enhance the security of interaction between massive Internet of things nodes, we propose a multidimensional attribute trust model and a dynamic maintenance mechanism of a trusted group. The proposed model provides a reference for the selection and evaluation of node multidimensional attribute factors to adapt to different Internet of things application scenarios. The dispersion of satisfaction records is used to discover abnormal data and weaken its influence on the calculation of the node's comprehensive trust evaluation. The construction of trusted groups provides an architectural foundation for the application of group signature that maintains low network overhead. The performance of multidimensional attribute trust model and dynamic maintenance mechanism is verified using Netlogo. Simulation results show the efficiency of the proposed model to classify the malicious nodes and honest nodes, as well as to build a trusted group that could ensure honest nodes occupy the major proportion. [ABSTRACT FROM AUTHOR]

In contrast to reactive inhibition, intentional inhibition is the internally generated decision to "stop" without any external signals. Whether adults and adolescents' neural correlates on these two inhibitions have any differences is still unknown. We measured 20 adults and 21 adolescents' ERP-related N2 using a free-choice Go/Nogo task. The results of the adult's group showed that the mean amplitude and peak latency of intentional Nogo-N2 did not differ from the reactive Nogo-N2. In contrast, the mean amplitude and peak latency for reactive Nogo-N2 in the adolescent group was significantly greater than what was observed for the intentional Nogo-N2. Comparison across groups revealed that the mean amplitude and peak latency of reactive Nogo-N2 were significantly greater in adolescents than in adults, while intentional Nogo-N2 did not differ between groups. These findings may indicate that adolescents lack of self-control is more reflected in reactive inhibition, if adolescents decide whether to do, they will be as good as adults. [ABSTRACT FROM AUTHOR]

Myocardial diseases usually appear ischemic. Reperfusion therapy is one of the effective methods that can improve clinical therapeutic efficacy. However, reperfusion results in myocardial injury named I/R injury. Rosuvastatin (RS) is HMG-CoA reductase inhibitor. We investigated the role of RS in the myocardial I/R injury in vitro and its active mechanism. Oxygen-glucose deprivation/reoxygenation (OGD/R) model was applied to investigate I/R in vitro. OGD/R decreased cell viability and increased levels of miR-17-3p and lactate dehydrogenase (LDH) leakage. Besides, RS decreased cleaved caspase-3 level and LDH leakage, promoted the levels of miR-17-3p and LC3II/LC3I, and increased cell viability when H9C2 cell was treated by OGD/R. miR-17-3p inhibitor reduced the H9C2 cell viability and LC3II/LC3I level, whereas miR-17-3p mimics increased H9C2 cell viability and LC3II/LC3I level. RS promoted cell viability and increased LC3II/LC3I level while it lowered LDH leakage, apoptosis rate, and the levels of cleaved caspase-3 and Cyto c. Our study suggested that RS reduced I/R injury in cardiocyte via cleaved caspase-3/Cyto c apoptosis signaling pathway and autophagy. Moreover, the autophagy happens to cardiocyte by upregulating the expression of miR-17-3p. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress (OS) has been implicated in age‐related neurodegeneration and may be important in prodromal states such as mild vascular cognitive impairment (mVCI). Higher peripheral OS is reported in mVCI patients; however, the role of central antioxidant defenses in mVCI is unclear. Glutathione (GSH) is a major brain antioxidant, and so brain GSH in possible mVCI vs. controls was assessed. Method: Possible mVCI patients (1 standard deviation (SD) below population norms in verbal memory, executive function (EF), processing speed, or working memory, age 55‐85, and currently enrolled in a cardiac rehabilitation program due to having 2 or more vascular risk factors or previous vascular event) and cognitively‐normal (CN) controls are recruited from a 6‐month exercise rehabilitation program. All participants received 1H magnetic resonance spectroscopy (MEscher–GArwood Point Resolved Spectroscopy) to quantify brain GSH at baseline in the anterior cingulate (AC) and occipital region (OC). Spectroscopic analysis was completed using the Gannet toolkit (vers. 3.1) in Matlab (vers. 2020b), a cut‐off of 20% was used to reject spectra of poor quality. Result: In 30 participants (mVCI n = 16, CN n = 14), anterior cingulate (AC) GSH (I.U. ± SD) was higher in mVCI (1.86 ± 0.45) compared to CN (1.63 ± 0.50) (F(1,18.8) = 4.6, P = 0.04), this difference became trending after correcting for cerebrospinal fluid volume ((F(1,18.2) = 3.9, P = 0.06). No difference was detected for OC‐GSH before or after correcting for cerebrospinal fluid volume. Higher AC‐GSH was correlated with lower Montreal Cognitive Assessment score (rho (26) = ‐0.42, p = 0.02). Conclusion: Preliminary data suggest an upregulation in anterior cingulate glutathione in mVCI, which might reflect a compensatory increase in antioxidants as a response to increase peripheral oxidative stress previously reported in these patients. Recruitment is ongoing and additional participants are needed to reinforce findings. [ABSTRACT FROM AUTHOR]

A novel electrochemiluminescence (ECL) closed bipolar electrode (BPE) chip was designed based on a hybridization chain reaction (HCR)-induced ECL amplification strategy for the detection of both DNA and H2O2. Without the utilization of a patterned ITO bipolar electrode (BPE), this chip platform consisted of an ITO glass coated with two layers of PDMS slices. The ITO cathode was modified with Au nanoparticles for further functionalization of biomolecules, which could also amplify the ECL signal at the anode of the BPE. Based on the specific hybridization and hybridization chain reaction (HCR), DNA sequences were greatly extended, leading to a significant increase in the resistance of the cathode. The reduction of H2O2 was inhibited on the cathode of the BPE, resulting in a quenching effect on the ECL intensity on the anode of the BPE. The designed biosensor displayed a satisfactory linear relationship for the detection of both DNA and H2O2. Therefore, the biosensor could not only be employed for DNA assays but also used in enzyme reactions based on the generation of H2O2. [ABSTRACT FROM AUTHOR]

We report the first results on Ge neutrinoless double beta decay from stage one of the China dark-matter experiment (CDEX). A p-type point-contact high-purity germanium detector with a mass of 994 g has been installed to detect neutrinoless double beta decay events, as well as to directly detect dark matter particles. An exposure of 304 kg d has been analyzed over a wide spectral band from 500 keV to 3 MeV. The average event rate obtained was about 0.012 counts per keV per kg per day over the 2.039 MeV energy range. The half-life of Ge neutrinoless double beta decay derived based on this result is T >6.4×10 yr (90% C.L.). An upper limit on the effective Majorana-neutrino mass of 5.0 eV has been achieved. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the safety and tolerability of palivizumab for RSV prophylaxis in high-risk children in everyday practice. Methods: High-risk children prophylaxed against RSV infection were recruited into a prospective, observational, Canadian RSV Evaluation Study of Palivizumab (CARESS) registry with active, serious adverse event (SAE) monitoring from 2008 to 2013. SAE reports were systematically collected and assessed for severity and relationship to palivizumab. Data were analyzed by Chi-square or Fisher Exact Tests to examine group differences in proportions. Results: 13025 infants received 57392 injections. Hospitalizations for respiratory-related illness (RIH) were reported in 915 patients, and SAEs other than RIH were reported in 52 patients. Of these, 6 (0.05%) patients had a total of 14 hypersensitivity reactions that were deemed possibly or probably related to palivizumab (incidence: 2.8 per 10,000 patient-months). The SAEs of 42 patients were assessed as not related to palivizumab. SAEs in the remaining 4 patients were not classifiable as their records were incomplete. There were no significant demographic predictors of SAE occurrence. Conclusions: Under active surveillance, a small proportion of infants in the CARESS registry experienced SAEs that had a potential relationship with palivizumab and these appeared to be unpredictable in terms of onset. Palivizumab appears to be a safe and well-tolerated antibody for RSV prophylaxis in high-risk children in routine practice. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence implicates oxidative stress (OS) in Alzheimer Disease (AD) and Mild Cognitive Impairment (MCI). Depletion of the brain antioxidant glutathione (GSH) may be important in OS‐mediated neurodegeneration, though post‐mortem brain GSH changes in AD have been inconclusive. Recent in vivo measurements of brain and peripheral GSH may shed light on GSH changes, with implications for its role as a biomarker and therapeutic target. Aim: To quantitatively review in vivo GSH in AD and MCI compared to healthy controls (HC) using meta‐analysis. Method: Studies published before June 2020 containing measurements of in vivo brain or peripheral GSH in MCI or AD with a HC group were identified using Medline, PsychInfo, and Embase. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for outcomes using random effects models. Outcome measures included brain GSH (Meshcher‐Garwood Point Resolved Spectroscopy (MEGA‐PRESS versus non) in AD and MCI, and peripheral GSH (intracellular versus extracellular) in AD and MCI. The Q statistic and Egger's test were used to assess heterogeneity and risk of publication bias respectively. Results: For brain GSH, 4 AD (AD=175, HC=272) and 4 MCI (MCI=254, HC=260) studies were included. For peripheral GSH, 26 AD (ADD=981, HCl=993) and 7 MCI (MCI=434, HC=408) studies were included. Brain GSH did not differ in AD or MC compared to HC; however, the subgroup of studies using MEGA‐PRESS reported lower brain GSH in AD (SMD [95%CI] = ‐1.47 [‐1.91, ‐1.02], p=0.02) and MCI (‐1.08 [‐1.53,‐0.64], p=0.01). Peripheral GSH was lower in AD (‐0.94 [‐1.37, ‐0.51], p<0.001). In a subgroup analysis, intracellular GSH was lower in MCI (‐0.66 [‐1.11, ‐0.21], p=0.02). Significant heterogeneity was observed in all analyses and supported the use of random effect models. Egger's test indicated risk of publication bias in MCI brain GSH literature. Conclusion: In vivo measures of GSH in AD and MCI had significant heterogeneity. Peripheral analyses suggested intracellular GSH decreases may be prominent in early disease stages with both intra‐ and extracellular decreases in later stages. Brain GSH may be decreased in AD and MCI but heterogeneity and potential bias indicate the need for measurement standardization and replication. [ABSTRACT FROM AUTHOR]

There are strong evidences to support that the modification of the characteristics of the second heart sound has a high correlation with the pulmonary arterial pressure (PAP). It is hence postulated that a specific heart sound spectrum for this disease group could be generated as a decision support system to help healthcare workers for the early detection of pulmonary hypertension. This paper described the design of a case-control study on identifying the heart sound pattern of people with pulmonary hypertension. In the proposed study, the heart sound of patients having pulmonary hypertension will be captured by an electronic stethoscope and processed into digital sound spectra which will be analysed to identify a specific heart sound pattern. In the future, an intelligent device will be developed based on the identified pattern to identify and diagnose early stage of pulmonary hypertension. [ABSTRACT FROM AUTHOR]

China's Belt and Road Initiative (BRI) will inevitably affect global energy cooperation. Along the Belt and Road, there are many developing countries. To understand the energy cooperation and development of these countries comprehensively is of great significance to guide their development and evaluate the impact of the BRI on the world energy and economic pattern. However, there is insufficient attention on those countries. Based on embodied energy analysis, a method which can track direct and indirect energy consumption in the economic system, effectively linking energy with the economy and environment, this paper proposes an evolution model of the embodied energy flow of the countries. Then, it simulates the evolution of the embodied energy flow under different cooperation strategies. The results show that if cooperation between countries positively affects their cooperation with other countries, adopting a mixed strategy is an advisable choice. On the contrary, cooperation with "powerful" countries in the network will be more conducive to the embodied energy flow. This article provides a new perspective and foundation for further discussion on the economy, trade, and energy cooperation along the Belt and Road. [ABSTRACT FROM AUTHOR]