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TiO2-supported Cux–(CoO)1−x/TiO2 catalysts exhibit high catalytic efficiency for NH3BH3 hydrolysis. The Cu–CoO interface provides bifunctional synergistic sites for H2 generation, with activation and adsorption of NH3BH3 and H2O on the surface of Cu and CoO, respectively.

Strong metal-support interactions characteristic of the encapsulation of metal particles by oxide overlayers have been widely observed on large metal nanoparticles, but scarcely occur on small nanoclusters (2 nm) for which the metal-support interactions remain elusive. Herein, we study the structural evolution of Pt nanoclusters (1.5 nm) supported on anatase TiO

Aims Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary arterial pressure, resulting in right ventricular overload, right heart failure and eventually death. Treprostinil is a prostacyclin analogue that is used in the treatment of PAH. As an orphan drug, limited information is available regarding its disposition and its use in special populations such as elderly, paediatric and pregnant patients. The objective of the current study was to develop a robust physiologically based pharmacokinetic (PBPK) model for treprostinil intravenous injection and extended-release tablet as the first step to optimize treprostinil pharmacotherapy in patients. Methods PBPK model was built using Simcyp simulator which integrated physicochemical properties, observed or predicted parameters for drug absorption, distribution and elimination for treprostinil, and population specific physiological characteristics. Three clinical trials after intravenous infusion and nine studies after oral administration of treprostinil extended-release tablet in healthy volunteers were used to develop and validate the model. The simulated PK profiles were compared with the observed data. Extrapolation of the model to patient populations including patients with hepatic impairment was conducted to validate the predictions. Results Most of the observed data were within the 5th and 95th percentile interval of the prediction. Most of the percentage error in the PK parameters were within ±50% of the corresponding observed parameters. The developed model predicted the lung exposure of treprostinil to be approximately 0.17 times of concentration in plasma. Conclusion Predicted absorption, distribution, and metabolic enzyme kinetics gave an insight into the disposition of treprostinil in humans. Extrapolation of the established model to patient populations with hepatic impairment successfully documented the model reliability. The developed model has the potential to be used in the PK predictions in other special patient populations with different demographic, physiological and pathological characteristics.

With the increasing growth of the herbal market, a rapid and easy-to-use system is highly desirable in the high-throughput identification of massive herbal medicine samples. Here, an ultrafast and colorimetric detection system was devised based on simplifying template preparation and a newly developed amplification technique, named colorimetric direct-VPCR. The system was successfully applied to the identification of Pinelliae Rhizoma. Compared to the traditional method, the whole test can be finished within 30 min from the sample treatment to the testing results. The method was evaluated by correctly identifying 72 samples obtained from 9 different habitats, demonstrating its high reliability. In summary, we present an ultrafast (less than 30 min) and colorimetric detection platform (under ultraviolet lamp) based on direct-VPCR for the identification of Pinelliae Rhizoma. The high practicability (100% accuracy) of this pipeline enables it to be a promising method in the routine detection of other herbal materials. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-03035-9.

Lead (Pb) is the most widely used anode in zinc (Zn) electrowinning and other metallurgical industries. The resource loss and environmental pollution caused by Pb anode corrosion are urgent problems to be solved. A γ-MnO

The accurate prediction of the highway traffic speed plays an important role in improving the production efficiency and the convenience of lives, and it is also one of the important issues in vehicle social big data analyses. Aiming at the problem of highway traffic speed data preprocessing, this paper proposes the algorithm of Redundant Data Reducing (RDR) that can greatly reduce the amount of data in model training of long short-term memory (LSTM) and improve the training speed under the condition that the influence on prediction accuracy is small and controllable. Aiming at the problem of low prediction accuracy for holiday traffic speeds due to small data volume, this paper proposes the Segment Prediction Algorithm (SPA) based on the speed features, which can effectively improve the prediction accuracy. The experimental results show that RDR can reduce the training data by up to 60% without notably affecting the prediction accuracy, while it improves the training speed by 60%. Compared with the current LSTM algorithm, the prediction accuracy of SPA improves significantly.

Isavuconazole (ISA) is an azole antifungal used in the treatment of invasive aspergillosis and mucormycosis. Patients with mild or moderate hepatic impairment have lower clearance (CL) than the healthy population. Currently, there are no data on ISA in patients with severe hepatic impairment (Child-Pugh class C). The purposes of this study were to build a physiologically based pharmacokinetic (PBPK) model to describe the pharmacokinetics (PK) of intravenous ISA and to predict changes in ISA disposition in different patient populations and in patients with hepatic impairment so as to guide personalized dosing. By incorporating the systemic and drug-specific parameters of ISA, the model was initially developed in a healthy population and was validated with 10 independent PK profiles obtained from healthy subjects and from patients with normal liver function. The results showed satisfactory predictive capacity; most of the relative predictive errors were within ±30% for the area under the concentration-time curve (AUC) and the maximum concentration of the drug in serum (C(max)). The observed concentration-time profiles of ISA in plasma were well described by the model-predicted profiles. The model adequately predicted the reduced CL of ISA in patients with mild or moderate hepatic impairment. Furthermore, the model predicted a decrease in CL of about 60% in patients with severe hepatic impairment. Therefore, we recommend reducing the dose by 50% in patients with severe hepatic impairment. The model also predicted differences in the PK of ISA between Caucasian and Asian populations, with a Chinese/Caucasian CL ratio of 0.67. The PBPK model of ISA that was developed provides a reasonable approach for optimizing the dosage regimen in different ethnic populations and in patients with severe hepatic impairment.

Lead (Pb) is the most widely used anode in zinc (Zn) electrowinning and other metallurgical industries. The resource loss and environmental pollution caused by Pb anode corrosion are urgent problems to be solved. A γ-MnO2 precoated anode was prepared successfully to reduce the Pb-containing pollutant. The size effects with its controllable preparation on an industrial scale were studied. Severe nonuniform distribution of γ-MnO2 film was observed with curbing the reduction of anode slime only 68%, when anode size increased from lab to industry. Nonuniform rate (R) and average thickness (d) were found to be the key indicators to determine the film structure distribution and their performance differences, which were random and difficult to be controlled in scale-up size. However, a controllable industrial γ-MnO2 precoated anodes (IMPA) fabricated through optimized current density (J0) and electrodeposition time (t) in our developed film-forming system. Then, the long-term performances of two IMPA with different indicators (IMPA-1: R = 34%, d = 108 μm, IMPA-2: R = 23%, d = 55 μm) were compared with the industrial typical Pb-based anode (ITPA). Of the three different anodes, the optimized IMPA-2 displayed the best performance. Within 24 d of electrowinning cycle, the corrosion inhibition effect and the anode slime reduction rate for IMPA-2 improved by 56% and 30% than IMPA-1, and improved by 100% and 91% than ITPA. Furthermore, the mechanism analysis of size effect change showed that R of IMPA was contributed to the local gas holdup distribution along the anode. Controlled size effect of uniform oxide film will have a future application prospect for the sustainability of industry, which provides an important cleaner production of Zn electrowinning and related hydrometallurgy industries.

Hepatolenticular degeneration (HLD) is an inherited disorder associated with human copper metabolism. Gandou decoction (GDD), a traditional Chinese medicinal formula, has been used as a therapeutic agent for the treatment of HLD in China for decades. Recent pharmacological evaluation in our laboratory has demonstrated that GDD exerts positive and beneficial effects on HLD model rats. However, its underlying therapeutic mechanisms are not yet well understood. To explore the potential therapeutic effects of GDD against HLD, liver and urine metabolomics approach combined with histopathological examination were performed to reveal the underlying mechanisms. Changes in metabolic profiles were estimated by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) coupled with multivariate statistical analyses. The results indicated that GDD could significantly improve liver pathological variations. Moreover, 19 and 11 significantly altered metabolites were found in the liver and urine between the normal and model groups, respectively. After GDD treatment, the levels of all these disordered metabolites showed different degrees of improvement compared with the model group, including lysoPC(18:2), lysoPE(20:2/0:0), PC(18:1/14:1), alpha-linolenic acid, sphinganine, taurochenodesoxycholic acid, tetracosahexaenoic acid, 13-OxoODE, and 13-L-hydroperoxyl inoleic acid. Metabolic pathway enrichment suggested that lipid and oxidative stress metabolism were the two main pathways that participated in copper-laden rat models with GDD administration. This work indicates that GDD could achieve a therapeutic effect on HLD by ameliorating the associated metabolic disturbances.

With the exacerbation of aging in China, the problem of nursing for the elderly has increasingly become one of the focuses of social concerns. Because of the popularization of mobile devices, using mobile devices to assist the care of the elderly has become a feasible solution. In this paper, we developed an elderly life assistant system (ELAS) based on mobile devices, which includes two apps (applications), i.e., the Supporter side and the Elderly side. The Supporter side helps the supporters to care for the elderly, remotely helps the elderly to input the drug information and record medication; the Elderly side assists the daily lives of the elderly. The main functions of the system are medication reminding, reading assistance, navigation route assistance and adaptive voice navigation (AVN), in which AVN can automatically adjust the volume of navigation according to external noise, providing better navigation effect for the elderly. Experiments show that ELAS is helpful to the elderly in daily life, and improves the ability of the elderly to take care of themselves.

The single degree of freedom mass-spring-damper system is the most common approach for deriving a full electromechanical model for the piezoelectric vibration energy harvester. In this paper, we revisit this standard electromechanical model by focusing on the impedance of the piezoelectric device. This approach leads to simple closed form expressions for peak power frequency, optimal load, and output power without a tedious mathematical derivative approach. The closed form expressions are validated against the exact numerical solution. The electromechanical model contains a set of only five lumped parameters which, by means of the piezoelectric impedance expression, all can be determined accurately by electrical measurements. It is shown how four of five lumped parameters can be determined from a single impedance measurement scan, considerably reducing the characterization effort. The remaining parameter is determined from shaker measurements, and a highly accurate agreement is found between model and measurements on a unimorph MEMS-based screen printed PZT harvester. With a high coupling term K 2 Q ≃ 7, the harvester exhibits two optimum load points. The peak power performance of the harvester was measured to 11.7 nW at an acceleration of 10 mg with a load of 9 kQ at 496.3 Hz corresponding to 117 μW/g 2 .

Multi-element transducers enabling novel cost-effective fabrication of imaging arrays for medical applications have been presented earlier. Due to favorable low lateral coupling of the printed PZT, the elements can be defined by the top electrode pattern, leading to a kerf-less design with low cross-talk between the elements. The linear arrays have proved to be compatible with a commercial ultrasonic scanner and to support linear array beamforming as well as phased array beamforming. The main objective of the presented work is to investigate the performance of the devices at the transducer level by extensive measurements of the prototype structures. The arrays have been characterized at the transducer level by several different measurement techniques. Firstly, electrical impedance measurements on several elements in air and liquid have been conducted. The arrays have also been characterized by a pulse-echo system. The measured sensitivity is around −60 dB, the fractional bandwidth is close to 60%, while the center frequency is about 12 MHz over the whole array. Finally, laser interferometry measurements have been conducted. The in-depth characterization of the array structure have given insight into the performance parameters for the array based on PZT thick film and the obtained information will be used to optimize the key parameters for the next generation of arrays based on piezoelectric thick film.

In this work a batch of MEMS-based vibration energy harvesters consisting of a silicon/PZT thick film ntilever with integrated proof mass is characterized. The purpose of a vibration energy harvester is to convert low grade vibrations to useful electrical power. Optimally, the natural frequency of the harvester should match the frequency of he ambient vibration. The first step to achieve this is to evaluate the uniformity of the fabricated harvesters and nderstand the effects of temperature on the harvesters during operation. Therefore, the uniformity of 40 energy harvesters from one wafer has been evaluated. Thereafter the performance of the energy harvesters operating at emperatures between -30 °C to 100 °C was measured.

This paper presents a homogeneity analysis of a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibration energy harvesters aimed towards vibration sources with peak vibrations in the range of around 300 Hz. A wafer with a yield of 91% (41/45 devices) has been characterized. Measurements of the open circuit voltage showed a relative difference of 32.6% between the standard deviation and average. Measurements of the capacitance and resonant frequency showed a relative difference between the standard deviation and average value of 4.3% and 2.9% respectively, thus indicating that the main variation in open circuit voltage performance is caused by varying quality factor. The average resonant frequency was measured to 333 Hz with a standard variation of 9.8 Hz and a harvesting bandwidth of 5-10 Hz. A maximum power output of 39.3 μW was achieved at 1 g for the best performing harvester.

Screen- and pad-printed single-element ultrasonic transducers have been successfully commercialized over the recent years. Typically, PZT (Lead Zirconate Titanate) thick films are pad- or screen-printed on a curved ceramic substrate acting as integrated backing layer and providing mechanical pre-focus. The center frequency ranges between 8 MHz and 80 MHz. The devices are characterized by good sensitivity as well as high relative bandwidth. The main objective of the presented work has been to apply a similar technology to manufacture multi-element transducers enabling novel cost-effective fabrication of imaging arrays for medical applications. The thick film arrays have been integration-tested using a commercial ultrasound scanner (BK Ultrasound bk3000). The integration test revealed that the 32-element thick film transducers are compatible with a commercial scanner, have a frequency range of 7.5 MHz to 12 MHz, and a TX bandwidth of 70%. Moreover, the transducers support linear array beamforming as well as phased array beamforming. Here 32-element transducers are presented, however the technology can easily be extended to fabrication of transducers with 128 or more elements.

We present a MEMS-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. The most common piezoelectric energy harvesting devices utilize a cantilever beam of a non piezoelectric material as support beneath or in-between the piezoelectric material. It provides mechanical support but it also reduces the power output. Our device replaces the support with another layer of the piezoelectric material, and with the absence of an inactive mechanical support all of the stresses induced by the vibrations will be harvested by the active piezoelectric elements.

We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using a mechanical front side protection of an SOI wafer with screen printed PZT thick film. The fabricated harvester device produces 14.0 µW with an optimal resistive load of 100 kΩ from 1g (g=9.81 m s−2) input acceleration at its resonant frequency of 235 Hz.

We describe the fabrication and characterization of a significantly improved version of a microelectromechanical system-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass; the harvester is fabricated in a fully monolithic process. The main advantage of bimorph vibration energy harvesters is that strain energy is not lost in mechanical support materials since only Pb(ZrxTi1-x)O3 (PZT) is strained; as a result, the effective system coupling coefficient is increased, and thus a potential for significantly higher output power is released. In addition, when the two layers are connected in series, the output voltage is increased, and as a result the relative power loss in the necessary rectifying circuit is reduced. We describe an improved process scheme for the energy harvester, which resulted in a robust fabrication process with a record high fabrication yield of 98%. The robust fabrication process allowed a high pressure treatment of the screen printed PZT thick films prior to sintering. The high pressure treatment improved the PZT thick film performance and increased the harvester power output to 37.1 ?W at 1 g root mean square acceleration. We also characterize the harvester performance when only one of the PZT layers is used while the other is left open or short circuit.

This work presents a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibrational energy harvesters aimed towards vibration sources with peak frequencies in the range of a few hundred Hz. By combining KOH etching with mechanical front side protection, SOI wafer to accurately define the thickness of the silicon part of the harvester and a silicon compatible PZT thick film screen-printing technique, we are able to fabricate energy harvesters on wafer scale with a yield higher than 90%. The characterization of the fabricated harvesters is focused towards the full wafer/mass-production aspect; hence the analysis of uniformity in harvested power and resonant frequency.

We describe fabrication and characterization of a significantly improved version of a MEMS-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. The main advantage of bimorph vibration energy harvesters is that strain energy is not lost in mechanical support materials since only PZT is strained, and thus it has a potential for significantly higher output power. An improved process scheme for the energy harvester resulted in a robust fabrication process with a record high fabrication yield of 98.6%. Moreover, the robust fabrication process allowed a high pressure treatment of the screen printed PZT thick films prior to sintering, improving the PZT thick film performance and harvester power output reaches 37.1 μW at 1 g.