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Antimicrobial photodynamic therapy has considerable promise in the fight against bacterial infections. The superior photophysical characteristics of porphyrins have made them effective photosensitizers in the field of phototherapy. Herein, the light-induced antimicrobial effects of three porphyrins with different substituents have been compared. 5,10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (THPP) shows superior photosensitizing activity and antimicrobial ability under irradiation with green light. THPP can also inhibit and destroy mature Staphylococcus aureus biofilms under irradiation. This work provides a reference for the rational design of photosensitizers for application in antimicrobial photodynamic therapy.

Aiming to provide low-cost MEC services for mobile devices in areas without/lacking infrastructure, we propose a renewable-energy-driven energy-harvesting-based task scheduling and energy management framework. First, for mobile devices, the constructed energy consumption minimization problem is solved by an alternating-optimization-based algorithm. Then, we design an energy management algorithm based on sampling average approximation to derive the optimal charging/discharging strategies, number of energy storage units, and renewable energy utilization. The simulation results show that the proposed framework can significantly reduce the cost of MEC servers and prolong the working hours of mobile devices.

Zr–Sn and Zr–Sn–Nb alloys were joined using current-induced solid-state welding. This process led to significant plastic deformation in Zr alloy, resulting in a robust welded joint. The Cu particles, oxides, and other impurities were scattered at the interface. Two distinct microstructures, basketweave-parallel-plate and basketweave-plate, emerged in the weld's center, attributable to varying thermal cycles. The average grain size in Zr–Sn–Nb alloy was smaller than in Zr–Sn alloy side. During the welding of Zr–Sn–Nb alloy, the majority of β-Nb secondary phases particles (SPPs) dissolved. Conversely, in Zr–Sn alloy, elongated, irregular ZrFe2 SPPs were observed between the α plates. The joint formation was influenced significantly by initial slip, twin-induced plasticity (TWIP), and transformation-induced plasticity (TRIP) mechanisms. The joint's burst force was measured between 8790 and 8890 N, and the fractures occurred at a location distant from the weld.

Introduction: Telehealth has been widely promoted and adopted at multiple levels in the U.S. healthcare system during the COVID-19 pandemic. However, this rapid expansion of telehealth services may have further exacerbated health inequities among marginalized groups. Methods: Using the 2020 National Health Interview Survey, this study compared patterns of telehealth use between people with functional disabilities and people without disabilities during the first year of the pandemic. Results: In the multivariable-adjusted logistic regression models, respondents with moderate disabilities were significantly more likely to report telehealth use, not pandemic related (OR=1.25, 95% CI=1.03, 1.52) and telehealth use, pandemic related (OR=1.43, 95% CI=1.28, 1.60) than people without disabilities. Similarly, respondents with severe disabilities were significantly more likely to report telehealth use, not pandemic related (OR=1.46, 95% CI=1.07, 2.00) and telehealth use, pandemic related (OR=2.06, 95% CI=1.72, 2.46). In addition, telehealth use varied by the number of limitations and disability type. Conclusions: People with functional disabilities were more likely to report telehealth use than people without disabilities. Furthermore, these associations strengthened with increasing disability severity and number of limitations while varying by disability type. Additional studies are warranted to explore ways of providing patient-centered telehealth to responsively meet various healthcare needs of people with functional disabilities and improve their health outcomes.

Chemotherapy has occupied the critical position in cancer therapy, especially towards the post-operative, advanced, recurrent, and metastatic tumors. Paclitaxel (PTX)-based formulations have been widely used in clinical practice, while the therapeutic effect is far from satisfied due to off-target toxicity and drug resistance. The caseless multi-components make the preparation technology complicated and aggravate the concerns with the excipients-associated toxicity. The self-assembled PTX nanoparticles possess a high drug content and could incorporate various functional molecules for enhancing the therapeutic index. In this work, we summarize the self-assembly strategy for diverse nanodrugs of PTX. Then, the advancement of nanodrugs for tumor therapy, especially emphasis on mono-chemotherapy, combinational therapy, and theranostics, have been outlined. Finally, the challenges and potential improvements have been briefly spotlighted.

Abstract Demineralized dentin matrix (DDM) is an osteoconductive and osteoinductive material that has been successfully used in sinus floor augmentation and alveolar ridge augmentation in clinical applications. It releases bone morphogenetic proteins (BMPs) and other growth factors, making DDM a suitable grafting material. However, the granular particle of DDM makes it difficult to anchor into the bone defect area. The aim of this study was to investigate the biological effects and osteoinductivity of the combination of DDM and Fibrin Glue (FG) at an optimal ratio on bone healing from a critical bone defect in an animal model. The mouse osteoblastic cell line (MC3T3-E1) was co-cultured with various ratios of DDM and FG to examine their effects on osteoblast proliferation and differentiation, as indicated by alkaline phosphatase (ALP) activity, osteocalcin (OC) production and mineralized nodules formation. The optimal ratio was then chosen for further study with a rabbit calvarial defective model, in which they were implanted with DDM or DDM-FG1 (1 g: 0.1 ml) and DDM-FG2 (1 g: 0.5 ml) compounds, or left blank for 2, 4, 8 and 12 weeks to investigate soft tissue and new bone regeneration. Micro-CT and histology analysis were used to evaluate the total grafting properties according to the different healing periods. The result from in vitro studies demonstrated that the ratio of 1:0.1 induced more ALP activity and mineralized nodules, while the ratio of 1: 0.5 (DDM-FG combined) induced more osteocalcin (OC) at specific time points. In the animal model, the 3D new bone volume in all DDM-FG treatment groups was significantly greater than that in the blank group at 2, 4, 8 and 12 weeks. Furthermore, the new bone volume was greater in DDM-FG2 when compared to the other groups during the early weeks of the healing period. In histological analysis, clusters of osteoblasts were formed adjacent to the DDM particles, and newly formed bone was observed in all groups, suggesting an osteoinductive property of DDM. Moreover, the greater new collagen synthesis observed at 4 weeks suggested that early bone healing was induced in the DDM-FG2 group. This study demonstrated that at an optimal ratio, the DDM-FG compound enhances osteogenic activities and bone regeneration.

Abstract Defects in insulin processing and granule maturation are linked to pancreatic beta-cell failure during type 2 diabetes (T2D). Phosphatidylinositol transfer protein alpha (PITPNA) stimulates activity of phosphatidylinositol (PtdIns) 4-OH kinase to produce sufficient PtdIns-4-phosphate (PtdIns-4-P) in the trans-Golgi network to promote insulin granule maturation. PITPNA in beta-cells of T2D human subjects is markedly reduced suggesting its depletion accompanies beta-cell dysfunction. Conditional deletion of Pitpna in the beta-cells of Ins-Cre, Pitpna flox/flox mice leads to hyperglycemia resulting from decreasing glucose-stimulated insulin secretion (GSIS) and reducing pancreatic beta-cell mass. Furthermore, PITPNA silencing in human islets confirms its role in PtdIns-4-P synthesis and leads to impaired insulin granule maturation and docking, GSIS, and proinsulin processing with evidence of ER stress. Restoration of PITPNA in islets of T2D human subjects reverses these beta-cell defects and identify PITPNA as a critical target linked to beta-cell failure in T2D.

This paper focuses on the design of a novel cooperative jamming strategy and resource allocation scheme in two-way energy harvesting (EH) relay networks. For solving the security vulnerability challenges, a backscatter jamming strategy is proposed by leveraging the information signals as the carrier, which can degrade the eavesdropping link without extra energy consumption, delay and strict synchronization requirement. Based on the above design, we formulate the secure energy efficiency (SEE) maximization problem by jointly optimizing the transmission powers of two sources, two different power splitting (PS) factors and time allocation factor. Although the resulting optimization problem is highly non-convex due to fractional objective function and multivariate coupling, an iterative algorithm is developed to convert the original problem into a tractable version and obtain the resource allocation solutions. Simulation results show that the achievable SEE of the proposed scheme is better than other conventional schemes.

Abstract Organic diradicaloids with unique open‐shell structures and properties have been widely used in organic electronics and spintronics. However, their advantageous optical properties have been explored less in the biomedical field. In this work, the photothermal conversion behaviors of a boron‐containing organic diradicaloid (BOD) are reported. BOD can assemble with 1,2‐distearoyl‐sn‐glycero‐3‐phosphoethanolamine‐poly(ethylene glycol) to form rodlike nanoparticles (BOD NPs). These as‐prepared BOD NPs exhibit high photothermal conversion capability and robust photothermal stability. Notably, they possess morphological superiority, which guarantees the effective photothermal therapy of tumors. This work thus demonstrates the promise of organic diradicaloids as efficient photothermal agents for biomedical applications.

Introduction: The COVID-19 pandemic has significantly disrupted the entire healthcare system, resulting in unmet needs for medical care (e.g., delayed or forgone care) among patients with cancer. Methods: Using 2020 National Health Interview Survey data, we examined the prevalence of unmet healthcare needs and whether the self-reported experience of having delayed or forgone healthcare is associated with increased emergency services use and hospitalizations. A multivariable logistic regression model was used to assess the associations between unmet healthcare needs because of COVID-19 and emergency services use and hospitalization, controlling for potential confounding. All analysis was conducted in March and April 2022. Results: Among 2,386 study participants living with cancer (representing 25.6 million U.S. adults), 33.7% reported having unmet healthcare needs because of the COVID-19 pandemic. The prevalence of unmet healthcare needs was higher among younger cancer survivors and those with higher education. In the adjusted analysis, cancer survivors with unmet healthcare needs were 31% more likely to report any emergency services use (adjusted OR=1.31, 95% CI=1.05, 1.65) than those without. Having unmet healthcare needs was not significantly associated with hospitalization (p=0.465). Conclusions: Our findings highlight the unmet need for cancer care because of the pandemic and potential adverse health outcomes.

This paper focuses on a mobile edge-computing-enabled heterogeneous network. A battery level-aware task-scheduling framework is proposed to improve the energy efficiency and prolong the operating hours of batterypowered mobile devices. The formulated optimization problem is a typical mixed-integer nonlinear programming problem. To solve this nondeterministic polynomial (NP)-hard problem, a decomposition-based taskscheduling algorithm is proposed. Using an alternating optimization technology, the original problem is divided into three subproblems. In the outer loop, task offloading decisions are yielded using a pruning search algorithm for the task offloading subproblem. In the inner loop, closed-form solutions for computational resource allocation subproblems are derived using the Lagrangian multiplier method. Then, it is proven that the transmitted power-allocation subproblem is a unimodal problem; this subproblem is solved using a gradient-based bisection search algorithm. The simulation results demonstrate that the proposed framework achieves better energy efficiency than other frameworks. Additionally, the impact of the battery level-aware scheme on the operating hours of battery-powered mobile devices is also investigated.

Abstract Developing highly efficient pharmaceuticals to eradicate pathogens and facilitate wound healing is of great concern. Despite some cationic carbon dots (CDs) have been used for sterilization, hardly any anionic CDs with antimicrobial activity have appeared. In the present work, we engineered a string of anionic CDs (especially CD31) as valid broad-spectrum bactericides to kill bacteria. Furthermore, CD31 conjugated with ɛ-polylysine (Plys) to construct injectable, and self-healing hydrogel (CD-Plys) that possess the advantages of remarkable broad spectrum antibacterial activity, excellent wound healing ability and satisfied biocompatibility. CD-Plys could dramatically accelerate wound healing with epithelization and enhanced angiogenesis. Taken together, this work provides a two-pronged strategy to explore CDs-based antimicrobial agents for disease therapy and tissue engineering.

ObjectiveThe ice resistance of an ice breaker on the Yellow River is predicted in the context of ice disasters caused by the freezing of the river in winter. MethodsFirst, a ship-ice-water coupled numerical model is introduced on the basis of the smoothed particle hydrodynamics method (SPH), which includes the numerical process of the constitutive equation, yield criterion and coupling model of ice. The prediction results for the ice resistance of the icebreaker under different conditions are then given. ResultsThe results show that the prediction error of ice resistance in level ice cases is less than 17.6% compared with empirical formulas; the ice resistance of the ice breaker increases with the increase in bending strength and ice thickness, and the thickness of the ice layer is the most important factor for the ice load.ConclusionThe ship-ice-water coupled SPH method proposed in this paper can predict the ice resistance of an ice breaker in the Yellow River channel, providing references for the actual operation of ice breakers on the Yellow River.

Abstract As a typical class of crystalline porous materials, metal–organic framework possesses unique features including versatile functionality, structural and compositional tunability. After being reduced to two-dimension, ultrathin metal-organic framework layers possess more external excellent properties favoring various technological applications. In this review article, the unique structural properties of the ultrathin metal-organic framework nanosheets benefiting from the planar topography were highlighted, involving light transmittance, and electrical conductivity. Moreover, the design strategy and versatile fabrication methodology were summarized covering discussions on their applicability and accessibility, especially for porphyritic metal-organic framework nanosheet. The current achievements in the bioapplications of two-dimensional metal-organic frameworks were presented comprising biocatalysis, biosensor, and theranostic, with an emphasis on reactive oxygen species-based nanomedicine for oncology treatment. Furthermore, current challenges confronting the utilization of two-dimensional metal-organic frameworks and future opportunities in emerging research frontiers were presented. Graphical Abstract

Water pollution due to heavy metals has become a universal environmental problem. Ni(II) is a common heavy metal ion in polluted wastewater, which has high toxicity and carcinogenicity. In this study, the structure of a calcium-iron layered double hydroxide (Ca-Fe-LDHs) was synthesized and characterized by FTIR, XRD, SEM and XPS. Then, Ni(II) ion was effectively removed by Ca-Fe-LDHs and its mechanism for this materials was described. The maximum adsorption capacity of Ni(II) for Ca-Fe-LDHs was 418.9 mg‧g−1 when the initial concentration of Ni(II) was 1 g/L. The adsorption and removal of Ni(II) by Ca-Fe-LDHs was attributed to the action of hydroxyl groups on the hydrotalcite, generating surface capture. Ni(OH)2)0.75(H2O)0.16(NiCO3)0.09, Ni(OH)2, NiO, NiSO4 and other precipitates were generated on its surface. And a small amount of Ni-Fe-LDHs was generated through isomorphic transition before hydrolysis. Therefore, surface capture and isomorphic transition enhanced the removal efficiency of Ni(II) with Ca-Fe-LDHs, making Ca-Fe-LDHs as a potential material for effective removal of Ni(II).

The ice, cloud, and land elevation satellite-2 (ICESat-2) can effectively measure global surface elevations and be used as a new data source for global elevation control. ICESat-2 has provided surface-specific data products on land/vegetation (ATL08), ice sheet (ATL06), inland water (ATL13), etc., but not on urban areas. The current research using ICESat-2 data to extract control points mostly based on products already provided, focusing on land, forest and other areas. Few studies have analyzed the feasibility of extracting control points in urban areas, as well as the position and elevation accuracy of control points. In this paper, we proposed a method for extracting high-accuracy control points from ATL03 in urban areas and evaluated the elevation and plane accuracy. First, building and ground photons were extracted and classified according to the photon shape features and neighborhood relationships, thereby addressing the insufficiency of ICESat-2 of not classifying photons in urban areas. Then, high-accuracy photons were selected from the ground photons as the laser control points considering the influence of land cover. Finally, the solid and undulating city outline was used for shape matching with DSM, thereby addressing the problem of plane accuracy evaluation in flat areas. We verified our method in two areas (Nanjing and Auckland) and showed that the method can adequately classify buildings and ground photons in different scenarios. The plane accuracy was better than 3.8 m, which lies well within ICESat-2′s mission requirement, with an elevation accuracy of better than 0.5 m, which meets the accuracy requirements of large-scale mapping, suggesting that photons in urban areas can also provide high-accuracy control data for stereo mapping.

The combination of tumor ablation and immunotherapy is a promising strategy against tumor relapse and metastasis. Photothermal therapy (PTT) triggers the release of tumor-specific antigens and damage associated molecular patterns (DAMPs) in-situ. However, the immunosuppressive tumor microenvironment restrains the activity of the effector immune cells. Therefore, systematic immunomodulation is critical to stimulate the tumor microenvironment and augment the anti-tumor therapeutic effect. To this end, polyethylene glycol (PEG)-stabilized platinum (Pt) nanoparticles (Pt NPs) conjugated with a PD-L1 inhibitor (BMS-1) through a thermo-sensitive linkage were constructed. Upon near-infrared (NIR) exposure, BMS-1 was released and maleimide (Mal) was exposed on the surface of Pt NPs, which captured the antigens released from the ablated tumor cells, resulting in the enhanced antigen internalization and presentation. In addition, the Pt NPs acted as immune adjuvants by stimulating dendritic cells (DCs) maturation. Furthermore, BMS-1 relieved T cell exhaustion and induced the infiltration of effector T cells into the tumor tissues. Thus, Pt NPs can ablate tumors through PTT, and augment the anti-tumor immune response through enhanced antigen presentation and T cells infiltration, thereby preventing tumor relapse and metastasis.

Abstract Redox-responsive drug delivery system emerges as a hopeful platform for tumor treatment. Dihydroartemisinin (DHA) has been investigated as an innovative tumor therapeutic agent. Herein, a DHA dimeric prodrug bridged with disulfide bond as linker (DHA2-SS) has been designed and synthesized. The prepared prodrugs could self-assemble into nanoparticles (SS NPs) with high DHA content (> 90%) and robust stability. These SS NPs display sensitive redox responsive capability and can release DHA under the tumor heterogeneity microenvironment. SS NPs possess preferable antitumor therapeutic activity in contrast with free DHA. Moreover, the possible anti-cancer mechanism of SS NPs was investigated through RNA-seq analysis, bioinformatics and molecular biological method. SS NPs could induce apoptosis via mitochondrial apoptosis pathway, as well as glycolysis inhibition associate with the regulation of PI3K/AKT/HIF-1α signal path, which may offer an underlying therapeutic target for liver cancer. Our study highlights the potential of using redox responsive prodrug nanoparticles to treat cancer, meanwhile provides insights into the anti-cancer mechanism of DHA prodrug. Graphical Abstract

Abstract Self‐assembled prodrug nanoparticles with tumor‐responsive capacity have great potential in tumor visualization and treatment. However, the nanoparticle formulas usually contain multiple components, especially polymeric materials, which result in various potential issues. Herein, we report an indocyanine green (ICG)‐driven assembly of paclitaxel prodrugs integrating near‐infrared fluorescence imaging and tumor‐specific chemotherapy. By feat of the hydrophilic merit of ICG, paclitaxel dimer could form more uniformly monodispersed nanoparticles. This two‐in‐one strategy reinforces the complementary advantages, resulting in superior assembly behavior, robust colloidal stability, enhanced tumor accumulation as well as desirable near‐infrared imaging and in vivo feedback of chemotherapy. The in vivo experiments validated the prodrug activation at tumor sites as evidenced by enhanced fluorescence intensity, potent tumor growth suppression, and reduced systemic toxicity compared with commercial Taxol. The universality of ICG potentiated strategy toward photosensitizers and fluorescence dyes was confirmed. This presentation provides deep insight into the feasibility of constructing clinical‐close alternatives for improving antitumor efficacy.

Cancer is a major health problem in the U.S and type 2 diabetes mellitus (T2DM) is known to increase the risk for the development of many cancers. Metformin, a first-line therapy for treating T2DM, is increasingly being used for its anticancer effects; however, the literature is limited on the effect of metformin dose on overall survival in patients with stage IV cancer. Overall survival was defined as the time interval from the date of diagnosis to the last known follow-up or death from any cause. Subjects who were alive on December 31, 2016 were censored. In this cohort study we examined the relationship between metformin dose and overall survival in persons with both T2DM and stage IV lung, breast, colorectal, prostate, or pancreas cancers. We used a retrospective study design with Cox proportional hazards regression analysis of the 2007–2016 of the Surveillance Epidemiology and End Results-Medicare (SEER) dataset. Of the 7,725 patients, 2,981(38.5%) had been prescribed metformin. Patients who used metformin had significantly better overall survival in both unadjusted (Unadjusted HR, 0.73; 95% CI, 0.69–0.76; p < 0.001) and adjusted models (adjusted HR, 0.77; 95% CI, 0.73–0.81; p < 0.001). The overall survival between patients who took metformin with average daily dose ≥ 1000mg or < 1000mg were not statistically significant (aHR, 1.00; 95% CI, 0.93–1.08; p = 0.90). Metformin use regardless of dose is associated with increased overall survival in older adults with stage IV cancer.

The low computational capacity of mobile devices has become the main performance bottleneck for emerging computing-intensive and delay-sensitive applications. In this paper, we propose a peer-to-peer (P2P) enhanced task scheduling framework to minimize the average task duration in device-to-device (D2D) enabled mobile edge computing (MEC) network by jointly optimizing the task scheduling decision and the computational resource allocation. Our proposed framework can work in different modes in different application scenarios. In the MEC mode, an iterative algorithm is presented based on alternating optimization technology and sorting algorithm, which can derive a near-optimal solution of the original mixed-integer non-linear programming (MINLP) optimization problem. In the P2P mode, we can reformulate the original problem to a typical one-to-one assignment problem, which is solved by a task scheduling algorithm based on the Hungarian method. In more challenging hybrid mode, we make some simplifications based on reformulation linearization technology. Then, the near-optimal solution is obtained by our proposed scheduling algorithm based on the alternating direction method of multipliers (ADMM) method and difference of convex functions (D.C.) programming. Numerical results show that our proposed framework has shorter average task duration under different scheduling modes compared with the other scheduling schemes.

For the self-energy recycling (SER) untrusted relay network, a two-phase destination-based jamming (DBJ) protocol is proposed, in which the destination transmits the jamming signal to reduce the received SNR of the untrusted relay node in the first phase and the relay node operated in full-duplex (FD) mode for simultaneous energy transfer and information relaying in the second phase. In addition, the loopback interference (LI) generated by FD relay node can be reused as part of energy. To satisfy some practical application scenarios, we consider the imperfect channel estimation error at the destination. Considering the total power constraint and the quality of service (QoS) requirement at the destination, the secrecy rate maximization problem is formulated by optimizing the transmission power of source and destination. However, the formulated problem is non-convex and difficult to solve directly. To cope with this difficulty, an iterative power allocation algorithm is proposed. The key idea of the proposed algorithm first integrates the non-convex constraint into the objective function by the exact penalty method. Then the difference of convex functions (DC) programming can be utilized to convert the non-convex objective function into the approximate convex function and the sub-optimal transmission power of source and destination can be obtained by the traditional convex programming. Simulation results show the superiority security performance of the proposed scheme with the traditional schemes.

Hibernation in ectotherms is well known, however, it is unclear how the circadian clock regulates endocrine and antioxidative defense systems of aquatic hibernators. Using the giant spiny frog (Quasipaa spinosa), we studied mRNA expression levels of (1) circadian core clock (Bmal1, Clock, Cry1 and Per2), clock-controlled (Ror-α, Mel-1c and AANAT), and antioxidant enzyme (AOE) (SOD1, SOD2, CAT and GPx) genes in retina, brain, and liver; and (2) plasma melatonin (MT) and corticosterone (CORT) levels, over a 24-hour period at six intervals pre-hibernation and during hibernation. Our results showed that brain Bmal1, Cry1, Per2 and Mel-1c were rhythmic pre-hibernation and Clock and Ror-α during hibernation. However, the retina Bmal1, Clock and Mel-1c, and plasma MT became rhythmic during hibernation. All brain AOEs (SOD1, SOD2, CAT and GPx) were rhythmic pre-hibernation and became non-rhythmic but upregulated, except SOD1, during hibernation. However, plasma CORT and liver clocks and AOEs were non-rhythmic in both periods. The mRNA expression levels of AOEs closely resembled those of Ror-α but not plasma MT oscillations. In the hibernating aquatic frogs, these modulations of melatonin, as well as clock and clock-controlled genes and AOEs might be fundamental for them to remain relatively inactive, increase tolerance, and escape hypoxia, and to prepare for arousal.

To design efficient nanoparticles for bioimaging, it is necessary to obtain nanoparticles with desired cellular uptake and biofunction. There are many studies have shown that cellular uptake largely depends on the geometric properties of nanoparticles. In this work, the organic nanoparticles with rod-like and spherical shapes were fabricated, and their cellular behaviors were studied and compared in detail via cellular uptake and bioimaging effect. The nanoparticles with spherical and rod-like morphology both can be internalized by HeLa and HepG2 cells, but the rod-like nanoparticles showed better imaging performance than their spherical counterpart. Above results presented that the rod-like nanoparticles possess great potential for bioimaging in efficient delivery and ideal imaging efficacy. Our studies may provide useful and fundamental information for designing efficient bioimaging systems.

A direct drive servovalve has some inherent benefits over its conventional counterparts, but also has better reliability and output power. However, due to the rigid connection between the spool and the motor, which takes the place of interstage drive-by fluid, the spool oscillation is a long-standing unsolved problem. In order to study the oscillation mechanism and the influencing factors, a double-circuit direct drive servovalve was numerically simulated. An oil return valve cavity was concentrated on as the main flow domain and was used to analyze the fluid flow characteristics. Local cavitation fraction and surface average cavitation fraction were defined to evaluate the cavitation situation. The periodic growth process of bubbles in the valve cavity was obtained. The numerical results show that bubbles in the oil return valve cavity changes, although the occurrence, evolution, and collapse stages were certain. The intensity of pressure pulsation caused by bubble variation is highly related to the bubbles causing the cavitation, which suggests a workable way to inhibit the spool oscillation.

The secure full-duplex (FD) simultaneous wireless information and power transfer (SWIPT) system and non-orthogonal multiple access (NOMA) have been deemed two promising technologies for the next generation of wireless communication. In this paper, the network is combined with device-to-device (D2D) and a practical bounded channel state information (CSI) estimation scheme. A system total transmit power minimization problem is studied and formulated as a multi-objective optimization (MOO) problem via the weighted Tchebycheff approach. A set of linear matrix inequalities (LMI) is used to transform the non-convex form of constraints into the convex form. Considering the imperfect CSI of the potential eavesdropper for robust power allocation, a bounded transmission beamforming vector design along with artificial noise (AN) is used, while satisfying the requirements from the secrecy rates as well as the energy harvesting (EH) task. Numerical simulation results validate the convergence performance and the trade-off between the uplink (UL) and downlink (DL) data transmit power. It is also shown that by FD and NOMA, the performance of the proposed algorithm is higher than that of half-duplex (HD) and orthogonal multiple access (OMA).

Summary: Inborn errors of metabolism (IEMs) occur with high incidence in human populations. Especially prevalent among these are inborn deficiencies in fatty acid β-oxidation (FAO), which are clinically associated with developmental neuropsychiatric disorders, including autism. We now report that neural stem cell (NSC)-autonomous insufficiencies in the activity of TMLHE (an autism risk factor that supports long-chain FAO by catalyzing carnitine biosynthesis), of CPT1A (an enzyme required for long-chain FAO transport into mitochondria), or of fatty acid mobilization from lipid droplets reduced NSC pools in the mouse embryonic neocortex. Lineage tracing experiments demonstrated that reduced flux through the FAO pathway potentiated NSC symmetric differentiating divisions at the expense of self-renewing stem cell division modes. The collective data reveal a key role for FAO in controlling NSC-to-IPC transition in the mammalian embryonic brain and suggest NSC self renewal as a cellular mechanism underlying the association between IEMs and autism. : The mechanisms underlying the association between inborn errors of fatty acid metabolism and developmental brain disorders such as autism remain unclear. Xie et al. find that TMLHE, a carnitine biosynthesis enzyme, and carnitine-dependent long-chain fatty acid β-oxidation control the neural stem cell pool during neocortical development by maintaining self-renewing divisions.

A simply and high selectively electrochemical method has been developed for the simultaneous determination of hydroquinone and catechol at a glassy carbon electrode modified with the poly L-methionine/multiwall carbon nanotubes, which significantly increased the reversible electrochemical reaction. The electrochemical behavior of catechol and hydroquinone at the modified electrode was studied by cyclic voltammetry and differential pulse voltammetry. The presence of hydroxyl MWCNTs in the composite film enhances the surface coverage concentration of poly L- methionine/multiwall carbon nanotubes. The results suggest that pH=6 is the optimum acidity condition for the selective and simultaneous determination of catechol and hydroquinone. Under the optimized condition, the response peak currents of the modified electrodes were linear over ranges of 8.0´10-7~2.0´10-4 mol/L (R2=0.997) for hydroquinone and 8.0´10-7~2.0´10-4, R2=0.997 for catechol. The sensor also exhibited good sensitivity with the detection limit of 8.0´10-8 mol/L and 1.0´10- 7 mol/L for hydroquinone and catechol, respectively. This study provides a new kind of composite modified electrode for electrochemical sensors with good selectivity and strong anti- interference. It has been applied to simultaneous determination of hydroquinone and catechol in water sample with simplicity and high selectivity.

In this paper, we propose a joint power allocation, time switching (TS) factor and relay selection scheme for an energy harvesting two-way relaying communication network (TWRN), where two transceivers exchange information with the help of a wireless-powered relay. By exploiting the TS architecture at the relay node, the relay node needs to use additional time slots for energy transmission, reducing the transmission rate. Thus, we propose a joint resource allocation algorithm to maximize the max-min bidirectional instantaneous information rate. To solve the original non-convex optimization problem, the objective function is decomposed into three sub-problems and solved sequentially. The closed-form solution of the transmit power of two sources and the optimal TS factor can be obtained by the information rate balancing technology and the proposed time allocation scheme, respectively. At last, the optimal relay node can be obtained. Simulation results show that the performance of the proposed algorithm is better than the traditional schemes and power-splitting (PS) scheme.

Three-dimensional fluorescence and infrared spectroscopy analysis of the leachate dissolved organic matter (DOM) of the Three Gorges was reported in spring, summer, and autumn seasons, respectively. Studies show that, that organic matter of landfill leachate in Yongchuan, Dazu and Jiangjin is the class of fulvic-like acid and protein-like fluorescence. The study also found that the longer the time of the pile of garbage, the lower the content of class of protein-like concentration, and the higher the concentration of fulvic-like acid, indicating that the protein waste material in the humification process is easy degradation. However, the same source of DOM is similar in the functional group composition and molecular structure. Characteristic frequency area analysis showed that humic acids (HA), and fulvic acids (FA) contain more than hydrophilic organic matter (HyI) aromatic ring structure, and FA aromatic ring structure is the most. Because of Chung-amide NH deformation vibration, there are strong absorption peaks in the 1562~1572 cm−1 for various components; HyI contains many organic nitrogen compounds and fatty acids.

There are various electrochemical approaches to save energy, mostly by means of equipment improvement coupled with other water treatment technologies. Replacement of DC power with pulse power, modified reactor coupled with photocatalysis can decrease cost. But more or less additional input is developed, or infrastructure has to be replaced. In this paper, an N-Step electrochemical reactor, based on stage reaction modeling, is put forward. On the basis of not changing equipment investment and by adjustment of the operating current density at different levels, power consumption decreases. This model develops a foundation of electrochemical water treatment technology for the engineering application.

In order to improve adsorption of macromolecular contaminants and promote the growth of microorganisms, active carbon for biological wastewater treatment or follow-up processing requires abundant mesopore and good biophile ability. In this experiment, biophile mesopore active carbon is produced in one-step activation with orange peel as raw material, and zinc chloride as activator, and the adsorption characteristics of orange peel active carbon is studied by static adsorption method. BET specific surface area and pore volume reached 1477 m2/g and 2.090 m3/g, respectively. The surface functional groups were examined by Fourier transform infrared spectroscopy (FT-IR). The surface of the as-prepared activated carbon contained hydroxyl group, carbonyl group, and methoxy group. The analysis based on X-ray diffraction spectrogram (XRD) and three-dimensional fluorescence spectrum indicated that the as-prepared activated carbon, with smaller microcrystalline diameter and microcrystalline thickness and enhanced reactivity, exhibited enhanced adsorption performance. This research has a deep influence in effectively controlling water pollution, improving area water quality, easing orange peel waste pollution, and promoting coordinated development among society, economy, and environment.

This experiment adopts the hypochlorite oxidation method to constantly synthesize potassium ferrate. Under the condition of micropolluted source water pH and on the basis of naphthalene, phenanthrene, and pyrene as research objects, the effects of different systems to remove aromatic hydrocarbons were studied. Various oxidation systems to remove phenanthrene intermediate are analyzed and the detailed mechanisms for removal of phenanthrene are discussed. The study found that the main intermediate of potassium ferrate system to transform phenanthrene is 9,10-phenanthraquinone and its area percentage reached 82.66%; that is, 9,10-phenanthraquinone is the key entity to remove phenanthrene.

The 3-Deazaneplanocin A (DZNep), one of S-adenosylhomocysteine (AdoHcy) hydrolase inhibitors, has shown antitumor activities in a broad range of solid tumors and acute myeloid leukemia. Here, we examined its effects on multiple myeloma (MM) cells and found that, at 500 nM, it potently inhibited growth and induced apoptosis in 2 of 8 MM cell lines. RNA from un-treated and DZNep treated cells was profiled by Affymetrix HG-U133 Plus 2.0 microarray and genes with a significant change in gene expression were determined by significance analysis of microarray (SAM) testing. ALOX5 was the most down-regulated gene (5.8-fold) in sensitive cells and was expressed at low level in resistant cells. The results were corroborated by quantitative RT-PCR. Western-blot analysis indicated ALOX5 was highly expressed only in sensitive cell line H929 and greatly decreased upon DZNep treatment. Ectopic expression of ALOX5 reduced sensitivity to DZNep in H929 cells. Furthermore, down-regulation of ALOX5 by RNA interference could also induce apoptosis in H929. Gene expression analysis on MM patient dataset indicated ALOX5 expression was significantly higher in MM patients compared to normal plasma cells. We also found that Bcl-2 was overexpressed in DZNep insensitive cells, and cotreatment with DZNep and ABT-737, a Bcl-2 family inhibitor, synergistically inhibited growth and induced apoptosis of DZNep insensitive MM cells. Taken together, this study shows one of mechanisms of the DZNep efficacy on MM correlates with its ability to down-regulate the ALOX5 levels. In addition, DZNep insensitivity might be associated with overexpression of Bcl-2, and the combination of ABT-737 and DZNep could synergistically induced apoptosis. These results suggest that DZNep may be exploited therapeutically for a subset of MM.

Memory formation is modulated by pre- and post-synaptic signaling events in neurons. The neuronal protein kinase Cyclin-Dependent Kinase 5 (Cdk5) phosphorylates a variety of synaptic substrates and is implicated in memory formation. It has also been shown to play a role in homeostatic regulation of synaptic plasticity in cultured neurons. Surprisingly, we found that Cdk5 loss of function in hippocampal circuits results in severe impairments in memory formation and retrieval. Moreover, Cdk5 loss of function in the hippocampus disrupts cAMP signaling due to an aberrant increase in phosphodiesterase (PDE) proteins. Dysregulation of cAMP is associated with defective CREB phosphorylation and disrupted composition of synaptic proteins in Cdk5-deficient mice. Rolipram, a PDE4 inhibitor that prevents cAMP depletion, restores synaptic plasticity and memory formation in Cdk5-deficient mice. Collectively, our results demonstrate a critical role for Cdk5 in the regulation of cAMP-mediated hippocampal functions essential for synaptic plasticity and memory formation.

Capping protein (CP) is a heterodimer that regulates actin assembly by binding to the barbed end of F-actin. In cultured nonneuronal cells, each CP subunit plays a critical role in the organization and dynamics of lamellipodia and filopodia. Mutations in either alpha or beta CP subunit result in retinal degeneration in Drosophila. However, the function of CP subunits in mammalian neurons remains unclear. Here, we investigate the role of the beta CP subunit expressed in the brain, Capzb2, in growth cone morphology and neurite outgrowth. We found that silencing Capzb2 in hippocampal neurons resulted in short neurites and misshapen growth cones in which microtubules overgrew into the periphery and completely overlapped with F-actin. In searching for the mechanisms underlying these cytoskeletal abnormalities, we identified beta-tubulin as a novel binding partner of Capzb2 and demonstrated that Capzb2 decreases the rate and the extent of tubulin polymerization in vitro. We mapped the region of Capzb2 that was required for the subunit to interact with beta-tubulin and inhibit microtubule polymerization. A mutant Capzb2 lacking this region was able to bind F-actin and form a CP heterodimer with alpha2-subunit. However, this mutant was unable to rescue the growth cone and neurite outgrowth phenotypes caused by Capzb2 knockdown. Together, these data suggest that Capzb2 plays an important role in growth cone formation and neurite outgrowth and that the underlying mechanism may involve direct interaction between Capzb2 and microtubules.