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Tooth wear is one of the most common faults in gear transmission systems. However, due to its limited influences on gear dynamics, the condition monitoring of gear wear experiences more challenges. To investigate the relationship between tooth wear and gear dynamics, this study develops an eight-degree of freedom dynamic model which takes into account the gear mesh impact induced by tooth wear. In this model, the gear mesh impact force induced by tooth wear was calculated as an extra input excitation for the gear dynamic model. Besides, a comparative study was carried out to explore the real reason that causes the poor dynamic behaviour due to the wear from two points of view: 1) the reduction in gear mesh stiffness; 2) the increase in gear mesh impact force. The simulation results show that the wear causes a slight reduction in gear mesh stiffness, thus leading to the decrease in the amplitude of gear mesh frequency. This is not consistent with the phenomena observed in the lab experiment which shows the increase in the gear vibrations. The second simulation of impact force demonstrates that the wear causes an increase in the impact force which further leads to the increase in the amplitude of gear mesh frequency. This study investigates the cause for the deterioration in gear dynamics induced by gear wear, which can benefit the early condition monitoring and fault diagnosis of the gear tooth wear.

The properties and performance of solid nanomaterials in heterogeneous chemical reactions are significantly influenced by the interface between the nanomaterial and environment. Oriented tailoring of interfacial dynamics, that is, modifying the shared boundary for mass and energy exchange has become a common goal for scientists. Although researchers have designed and constructed an abundance of nanomaterials with excellent performances for the tailoring of reaction dynamics, a complete understanding of the mechanism of nanomaterial-environment interfacial interaction still remains elusive. To predictively understand the nanomaterial-environment relationship over a wide range of time scale, a deep and dynamic insight is required urgently. In this Account, our recent works including advances in the design and construction of nanoassembled interfaces and understanding the dynamic interaction mechanisms between different combinations of nanoparticle (NP) assembly environment interfaces for tailoring the reaction dynamics.NP assemblies with well-defined structures and compositions are inherently suitable for replacing bulk-type nanomaterials for the research on interfaces. We primarily introduced two most relevant nanoassembled surfaces that were fabricated in our laboratory, namely, ordered self-assembly interface and animate nanoassembled interface. The disordered nanoparticles can be arranged into an ordered superlattice based on the self-assembly method and patterned-assembly method. In addition, we used NPs with flexible properties to construct three-dimensional (3D) animate assemblies. On the basis of a thorough understanding of the structure-property correlation, a series of nanoassembled interfaces with various structures have been developed for practice. In comparison with traditional nanomaterial-environment interfaces, the nanoassembled interfaces can change the mode of contact between the nanomaterial and environment, thereby maximizing the number of active sites and driving interferent/product off the nanoassembled interface. The geometry, porosity, and deformable/motional properties in the nanoassembled interface can be applied to enhance the mass transfer dynamics in the chemical reaction. Moreover, the nanoassembled interface can be used to strengthen the affinity between the NP assemblies and targets, thereby enhancing the adsorption efficiency. As shown in these examples, the nanoassembled interface can effectively change the speed, intensity, and mode of interactions between the NP assemblies and environment in spatiotemporal scales.The overall performance of the interfacial dynamics can be improved by the nanoassembled interface, thereby facilitating practical application in flowing systems. We have extended the applications of nanoassembled interfaces from simple adsorption to complex reactions in flowing systems, including in vivo magnetic resonance imaging, electrocatalytic gas evolution reaction, bacterial capture, sensing of exhaled volatile organic compounds, and heterogeneous catalysis. Our current endeavors to explore the applicability of animate nanoassembled interfaces for dynamic tailoring have widened the scope of research, and attempts to construct intelligent interfaces for applications are underway.

The application of intraoperative neural monitoring (IONM) trouble-shooting algorithms procedures in transoral endoscopic thyroidectomy vestibular approach (TOETVA) was investigated. Loss of signal (LOS) is defined as a loss of the primary electromyographic (EMG) normal biphasic waveform with reduced amplitude response to less than 100μV with a stimulation level intensity of 1–2mA. A systematic review of the IONM system at LOS was covered methodically: (i) correct endotracheal tube verification, (ii) stimulation of the recurrent laryngeal nerve (RLN) at entry point, (iii) ipsilateral or contralateral vagal nerve (VN) stimulation, and (iv) laryngeal twitch (LT). The function of 223 nerves at risk (NAR) was recorded with IONM. Twenty-seven (12%) NAR experienced a suspected LOS. LT could not be appreciated. In 15/27 (55%) cases, the application of the IONM trouble-shooting algorithm revealed upward displacement of the EMG tube (all orotracheal intubations). In 9 (4%) NAR, VN stimulation was not accomplished. In detail, there were n.5 left and n. 4 right VNs. Two VNs were ipsilateral, and 7 VNs contralateral. For EMG tube displacement, because the oral/nasal area is included in the aseptic field, it is less possible to re-check by the laryngoscope or fiberscope. A limit for applying the IONM trouble-shooting algorithm to TOETVA is determined by (a) inability to appreciate the LT, (b) difficulty in stimulating the ipsilateral and contralateral VN, and (c) remodeling EMG endotracheal tube position. A modified IONM trouble-shooting algorithm for TOETVA is proposed.

The aim of this report was to summarize observations, evaluate the feasibility, provide detailed information concerning proper techniques, and address limitations for non-recurrent laryngeal nerve (NRLN) dissection and release during the robotic bilateral axillo-breast approach (BABA) for thyroidectomy. The BABA approach was used in two cases of thyroidectomy in the setting of NRLN. Preoperative CT imaging findings suggesting the aberrant anatomy are reviewed and technical planning, inclusive of intraoperative nerve monitoring, was employed. Intraoperative videos with narrative discussion of technique for safe dissection are provided, along with supplementary video of additional technical guidance. In both cases, the NRLNs were identified, dissected, and preserved. We dissected the proximal segment of each NRLN to its origin. We determined that the use of only the NRLN proximal to distal robotic dissection jeopardized the nerve. The BABA approach with the Type I NRLN is similar to the dissection of the recurrent laryngeal nerve (RLN) in transoral thyroidectomy. Due to interference with endoscopic viewing caused by the thyroid cartilage, the Type I NRLN is more challenging to manage both at the laryngeal entry point and its origin from the vagus nerve (VN). For the Type II NRLN, it is essential to identify its point of origin and the reflection of the nerve from the VN. Therefore, modification of nerve dissection to mirror open surgery with bidirectional nerve dissection assisted in avoidance of traction injury to the nerve. We presented a video, a detailed description of methods, and discussed limits for NRLN management in robotic BABA. This report included (i) a description of the aberrant anatomy and CT scans to inform surgeons of the possible NRLN locations, (ii) a description of a technique for using the nerve monitor in the robotic surgeries, and (iii) a description of the techniques used to isolate and protect the NRLN during the robotic surgery. In robotic BABA, our NRLN-sparing technique and degree included mainly a multi-directional nerve dissection (i.e., medial-grade, later-grade approach together with proximal to/from distal) using athermal technique. The NRLN-sparing technique is predominantly carried out in an anterior dissection plane.

Anomaly detection has been widely studied and used in diverse applications. Building an effective anomaly detection system requires researchers and developers to learn complex structure from noisy data, identify dynamic anomaly patterns, and detect anomalies with limited labels. Recent advancements in deep learning techniques have greatly improved anomaly detection performance, in comparison with classical approaches, and have extended anomaly detection to a wide variety of applications. This tutorial will help the audience gain a comprehensive understanding of deep learning based anomaly detection techniques in various application domains. First, we give an overview of the anomaly detection problem, introducing the approaches taken before the deep model era and listing out the challenges they faced. Then we survey the state-of-the-art deep learning models that range from building block neural network structures such as MLP, CNN, and LSTM, to more complex structures such as autoencoder, generative models (VAE, GAN, Flow-based models), to deep one-class detection models, etc. In addition, we illustrate how techniques such as transfer learning and reinforcement learning can help amend the label sparsity issue in anomaly detection problems and how to collect and make the best use of user labels in practice. Second to last, we discuss real world use cases coming from and outside LinkedIn. The tutorial concludes with a discussion of future trends.

β-lactam–resistant Gram-negative bacteria with decrease in stiffness can be more efficiently penetrated by sharp nanowires., β-Lactam–resistant (BLR) Gram-negative bacteria that are difficult or impossible to treat are causing a global health threat. However, the development of effective nanoantibiotics is limited by the poor understanding of changes in the physical nature of BLR Gram-negative bacteria. Here, we systematically explored the nanomechanical properties of a range of Gram-negative bacteria (Salmonella, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae) with different degrees of β-lactam resistance. Our observations indicated that the BLR bacteria had cell stiffness values almost 10× lower than that of β-lactam–susceptible bacteria, caused by reduced peptidoglycan biosynthesis. With the aid of numerical modeling and experimental measurements, we demonstrated that these stiffness findings can be used to develop programmable, stiffness-mediated antimicrobial nanowires that mechanically penetrate the BLR bacterial cell envelope. We anticipate that these stiffness-related findings will aid in the discovery and development of novel treatment strategies for BLR Gram-negative bacterial infections.

The role of exogenous methyl jasmonate (MeJA) in alleviating drought stress was investigated on

Previous studies overlooked dynamic properties of NP assemblies; therefore, we highlight recent advances in animate properties., Nanoparticle (NP) assemblies are among the foremost achievements of nanoscience and nanotechnology because their interparticle interactions overcome the weaknesses displayed by individual NPs. However, previous studies have considered NP assemblies as inanimate, which had led to their dynamic properties being overlooked. Animate properties, i.e., those mimicking biological properties, endow NP ensembles with unique and unexpected functionalities for practical applications. In this critical review, we highlight recent advances in our understanding of the properties of NP assemblies, particularly their animate properties. Key examples are used to illustrate critical concepts, and special emphasis is placed on animate property-dependent applications. Last, we discuss the barriers to further advances in this field.

To obtain the compatibility of interstocks crossing with ‘Yuanxiaochun’, we performed a comparative analysis with five interstocks. From the 60th to 240th day after grafting, there was a significant difference between different treatments. All the new shoot/interstock diameter ratios were

Continuous intraoperative neural monitoring (C-IONM) is a promising technology used to decrease recurrent laryngeal nerve (RLN) damage during thyroid surgery. However, C-IONM use is limited due to its challenging application. C-IONM requires dissection of the carotid sheath and placement of an electrode around the vagus nerve (VN). In our study, we simultaneously stimulated and monitored the proximal RLN trans-tracheally using surface electrodes that were positioned solely on the endotracheal tube.We described the design, implementation, and testing of a pre-prototype, combined stimulating and recording endotracheal tube (SRET) that continually delivered current from tube edge, and tested the function of the RLN at the vocal cords (VC). The SRET was tested in vivo on 10 RLNs using 5 pigs as animal models.The SRET was capable of the following, delivery of continuous trans-tracheal stimulation to the proximal RLN, continuous trans-tracheal stimulation-induced VC movement, and standard ipsilateral RLN biphasic waveforms with latency and amplitude; and recording evoked responses were recorded in the ipsilateral RLN.The pre-prototype SRET represents a possible advancement in technology because it simplified the C-IONM. Thus, the SRET provides a minimally invasive, alternative application to the C-IONM vagal nerve cuff electrodes.

Gas-sensing applications commonly use nanomaterials (NMs) because of their unique physicochemical properties, including a high surface-to-volume ratio, enormous number of active sites, controllable morphology, and potential for miniaturisation. NM-based gas sensors, as a noninvasive, real-time technique, are a promising candidate for monitoring human breath. This review focuses on NM-based gas sensors used for breath diagnosis. First we describe some representative biomarkers of diseases that are detectable in breath and requirements for breath sensors. Then we review electrical, optical and mass-sensitive gas sensors in terms of these performance requirements, together with describing the detection capability of these sensors for trace concentrations of biomarkers and their initial attempts to diagnose disease. Moreover, we discuss breath sensor platforms with a multivariable sensing system, wireless communication and breath sampling, essential for predictive, preventive, personalised, and participatory (“P4”) medicine. Finally, we conclude with problems and challenges associated with the selectivity, humidity and validation of breath sensors. We hope that this article will inspire the development of high-performance gas sensors based on novel NMs.

Objective We assess the value of carbon nanoparticles (CNP) staining in patients undergoing endoscopic thyroidectomy and central compartment lymph node (CLN) dissection via the bilateral areola approach [endoscopic thyroidectomy via bilateral areola approach (ETBAA)]. Methods This was a prospective randomized study. Three hundred two consecutive early-stage thyroid cancer patients eligible for ETBAA were recruited at the Division of Thyroid Surgery, China-Japan Union Hospital, Jilin University, China. CLN were mapped and retrieved under the guidance of stained or unstained CNP. The location, detection rates, positive nodes, and number of stained lymph nodes were compared. Results ETBAA patients were randomly divided into a CNP group (n=152) and a control group (n=150). In the CNP group, the imaging of lymphatic flow could be observed in 1016 (95.9%) lymph nodes, whereas 43 (4.1%) were unstained. The mean number of stained lymph nodes in each procedure was 6.68 (range, 3 to 12). The total number of dissected lymph nodes was 1059 in the CNP group and 872 in the control group (P=0.00). There was a significant difference of inadvertent parathyroidectomy between the 2 groups: 0.5% versus 3.9% in lobectomy (P=0.035) and 0.6% versus 5.2% in total thyroidectomy (P=0.012). However, the rates of hypoparathyroidism were not significantly different (P>0.05). There were no cases of CNP-related adverse effects. Conclusions The lymphatic navigation by CNP increases the number of detected CLN without the involvement of radioactive isotopes. However, CNP did not lower hypocalcemia, did not improve parathyroid hormone range, and there was no significant difference in the percentage of metastatic lymph nodes between the 2 groups.

In gear transmission systems, the gear tooth surface will get inevitable worn due to various abnormal working conditions. The wear on gear tooth surface will cause deformation of the gear tooth profile. Furthermore, the wear will cause changes in gear tooth mesh stiffness, then deteriorate the gear dynamics. In the past decades, a number of studies had been carried out to investigate the process of gear tooth wear and its monitoring techniques. However, the interactions between the gear dynamics and gear tooth wear are still not got fully investigated. Therefore, this study proposed an eight-degree of freedom dynamic model to study the dynamic behaviours of the gear system with gear wear. When modelling the dynamic behaviours, a modified time-varying mesh stiffness (TVMS) model was derived by employing the potential energy method. The numerical results show that with the increase of the wear depth, the amplitudes at 1 × fm1 and 2 × fm2 increase gradually which can reflect the progressive wear process. Furthermore, an experimental study was conducted based on a run-to-fatigue test and the gear vibration responses were studied using the well-known de-noising method Time synchronous averaging (TSA). The experimental validation has a good consistency with the numerical analysis.

Background Mental nerve (MN) injuries are reported during transoral endoscopic thyroidectomy vestibular approach. Effect of trocar insertion and position on MN are examined in the present study. Materials and methods Ten millimeter incision was made at the center of the lower lip oral vestibule. Two 5 mm lateral incisions of the lower lip oral vestibule were made at the junction between the incisor and the canine. These 2 lateral incisions were high, just below the edge of lower lip. Nine pigs (18 MN) were randomly divided into 3 groups and MN dissection was performed. The angle between the lateral ports and median line were changed between 15 and 45 degrees among 3 groups and effect on MN was examined. Results During dissection when insertion and other ports are in neutral position visual inspection of MNs did not reveal any compression bilaterally. The distance between MN and the ports was 18.2±2.1 mm (16.3 to 21.2 mm). In group I and group II, MNs have no compression by the lateral trocars. In group III (45 degrees), left MNs were all compressed. Two MNs (66.7%) were compressed on the right side. The MN was compressed at its ramification. Conclusions The results of the present experimental study, endorse the suggested medial and lateral vestibular incisions for transoral endoscopic thyroidectomy vestibular approach. However, during dynamic modification of the lateral port position/angle, MN compression was observed when the angle was >45 degrees.

In this paper, Shimian yellow citrus fruit was used as material to study the differences of HuangGuo citrus fruit strains by sampling, measuring and analyzing the fruit quality according to different shapes and canopy. The results showed that: in the yellow fruit citrus plants fruit quality was better than the performance of the lower part of the upper canopy, appearance quality did not change significantly, little difference; intrinsic quality significantly different soluble solids and sugar content than other obvious difference; round tree fruit quality was better than natural growth happy shape and form.

As the contact point and contact path seriously affect the spiral bevel gear mesh characterize, the tooth modification method was applied to manufacture, and tooth contact markers can verify the contact area. However, when the contact area wear happen, the actual contact area may be changed which is not the expectation. And hence, the spiral bevel gear transmission is more sensitive to wear compare with parallel shaft gear transmission. The vibration response would reflect the wear severity. Nonetheless, the relative motion of spiral bevel gear contacting areas, which cause tooth surfaces wear, is rather complex on account of time-vary proportion of rolling and sliding. Moreover, the wear is not uniform, if there were some defects on the surface, the wear would intensify the defect. Modulation signal bispectrum (MSB) has been proven to be an effective monitoring approach which is sensitive to gear tooth defect. Spiral bevel gear tooth modification, which can change the contact area, is very important to the dynamic performance. To assess the improvement of the modification to tooth wear, a run-to-failure experiment of modification spiral bevel gear was carried out under accelerated wear conditions, and MSB method is applied to analysis the gearbox housing vibration signal to indicate the wear progress. The experimental results demonstrated the accuracy and reliability of the MSB-SE monitoring approach proposed.

We propose a scheme to engineer strong steady-state mechanical squeezing via the joint effect between Duffing nonlinearity and two driving tones in an optomechanical system. It is found that the joint effect can achieve strong squeezing exceeding 3 dB when the amplitude ratio of two driving tones is large enough. Moreover, the generated squeezing can be flexibly manipulated by increasing the red-detuned laser power and selecting the amplitude ratio of two driving lasers. The robustness of mechanical squeezing set up by the joint effect to the thermal noise can be improved benefiting from the enhancement of red-detuned laser power. Furthermore, we present that the mechanical squeezing can be directly detected by homodyning the cavity output field under an appropriate phase.

BACKGROUND The purpose of this work was to compare methods of detecting nonrecurrent laryngeal nerves (NRLNs). METHODS Specificity and sensitivity were compared in three NRLN detection methods: CT, electromyography (EMG), and A-B point comparison. RESULTS A total of 73 intraoperative pictures and 36 CT details of NRLNs are presented. Incidence of NRLN was 0.39%. Type I NRLN accounted for 50.7%, type IIA 45.2%, type IIB 4.1%. The NRLN median latency was 2.13 ms vs 3.00 ms median in an RLN control group (P

To design functional nanomaterials for biomedical applications, the challenge for scientists is to gain further understanding of their unique toxicological properties. Nonspecific adhesion of proteins and endocytosis are considered to be the major biotoxic sources of imaging nanoprobes. Here, we fabricated ultrathin gadolinium oxide (Gd2O3) nanocoils with a low Young’s modulus, which provides transformable properties in solution. The spatial configurational freedom of ultrathin nanocoils induces the steric repulsion to the nonspecific adsorption of proteins that, in turn, suppresses cellular uptake and thus improves their biocompatibility. The larger number of exposed surface gadolinium atoms of the ultrathin nanocoils provided enhanced T1 magnetic resonance (MR) imaging contrast with high signal activation. Such nanocontrast agents were applied to in vivo MR bioimaging to achieve prolonged circulation lifetime. The improved biocompatibility by transformable Gd2O3 nanocoils could open up a new perspective...

OBJECTIVE The aim of this report was dual: (a) to describe the step by step standardized intraoperative neural monitoring (IONM) procedure for recurrent laryngeal nerve (RLN) and external branch of the superior laryngeal nerve focusing on percutaneous IONM method, and (b) evaluation and outcomes of intermittent IONM in 237 endoscopic thyroidectomy via bilateral areolar approach cases. MATERIALS AND METHODS A 10-mm curved incision is made along the margin of the right areola at the 2 to 4 o'clock position for the 30-degree endoscope. Bilaterally 5-mm incisions are required on the edges of the areola at the 11 to 12 o'clock positions as accessory operating ports. Ball-tip, monopolar, single-use, standard stimulating probe with a 10-cm handle and 9-cm shaft is adopted percutaneously for IONM. As reference, on the dominant thyroid lesion side, a 0.5-cm circle is drawn with the center at the intersection of a line 2-cm lateral to the anterior median line and a line 2-cm above the line connecting the bilateral clavicular heads. After ensuring with ultrasonography that no vessels are within the puncture passage, the skin is pierced with an 18-G syringe needle. After withdrawing the needle, the probe is carefully inserted through the tract. IONM is performed according to standards of equipment set up, anesthesia, tube positioning verification tests, and electromyography determinations. RESULTS A total of 277 nerves at risk were favorably monitored with percutaneous probe stimulation. RLN, vagus nerve, and external branch of the superior laryngeal nerve were successfully determined. There were no instances of IONM malfunction, equipment displacement, or interference with the other endoscopic instruments. IONM probe insertion incision determined no scarring or morbidity in the neck. The incidence of RLN monolateral temporary palsy was 6%. CONCLUSIONS Standardized monitoring in endoscopic thyroidectomy via bilateral areolar approach is feasible. IONM was implemented by means of percutaneous stimulating probe.

Redesigning heterogeneous catalysts so that they can simultaneously integrate the efficiency and durability under reaction environments with respect to gas fuel production, such as hydrogen (H2), o...

Gears are important components of the transmission system. Tooth wear and bearing clearance are significant factors affecting the dynamics of the gear system. In order to reveal the effects of gradual wears and bearing clearance on the gear system dynamics, a six-degrees-of-freedom bending-torsion coupled model of gear-rotor-bearing which considers surface wear, bearing clearance and backlash is established. The Rung-Kutta method is used to solve the nonlinear dynamic system, and the dynamic responses of the system are obtained. The results show that the time-varying mesh stiffness decreases with the tooth surface from the unworn phase to severe wear phase. At the same time, the change of the mesh stiffness in the double-tooth mesh area and single-tooth area are different. Moreover, the amplitude of the X-displacement, Y-displacement and relative gear mesh displacement will be enlarged slightly with the increase of wear depth or bearing clearance. By analyzing variation tendency in the frequency domain, the different order harmonics show the different change characteristic with the variation of the wear phases or bearing clearances. This study provides a theoretical basis for improving the transmission performance and the selection of the bearing clearances in the gear system.

Background In this study, we aimed to compare the kinetics of intact parathyroid hormone (iPTH) during the perioperative period of endoscopic thyroidectomy via bilateral areola approach (ETBAA) in the same period, following a traditional open thyroidectomy approach (OTA). Methods We conducted a prospective observational study of patients who were undergoing thyroidectomy and level VI clearance. Patients who had been affected by papillary thyroid cancer (PTC) were stratified into three groups: those eligible for endoscopic treatment (ETBAA); patients who were eligible for ETBAA but had opted for OTA (OTA-L); and patients who were not suitable for endoscopic intervention (OTA-H). A process for locating parathyroid glands was utilized to stratify gland dissection laboriousness. In Type A, the gland is firmly fixed to thyroid gland. This type can be sub-classified into three subtypes. A1: the parathyroid gland is attached to the inherent thyroid capsule. A2: the gland is partially embedded in the thyroid gland. A3: the gland is located in the thyroid tissue. Type B is defined as a gland which is separated from the thyroid gland. The iPTH was sampled at wound closure. Results There were 100 patients in each group. We found a significant difference between the ETBAA and OTA-H groups for type A2, as well as a loss of parathyroid glands and a number of parathyroid transplantation procedures. The endoscopic group was treated during an earlier stage of thyroid cancer. The iPTH profile of each group decreased, although this was the most consistent in the OTA-H group. A comparison of ETBAA with OTA-L demonstrates that the iPTH level change is similar. Conclusion There is no advantage of endoscopic treatment for preserving parathyroid function.

The vast rural areas, which contain historical, cultural heritage and natural resources areas are the root for the stability of China and the foundation of the Chinese nation. However, excessive urban development and construction has affected these smaller rural villages, which were left behind due to China’s rapid economy. This is a design study of the ‘Beautiful Village’ Project, initiated by the local government, in order to demonstrate an opportunity to redesign the rural areas. This paper exhibits the experiences and impressions of the architects from China Central Academy of Fine Arts who took part in the architecture design for the villages. In order to achieve this, a series of investigation and analysis was done by the architects to reveal the present situation of the villages in China. Additionally, the active participation of the villagers is crucial in the successful re-development of the area. The main objective of this paper is to therefore identify the difficulties and problems encountered by the village and to propose a counter solution in order to design a better living condition for the rural areas of China.

Owing to the diversity of lipids, profiling and imaging multiple classes of lipids in one analysis by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MSI) is a great challenge. In this work, polyvinylpyrrolidone (PVP) capped silver nanoparticles (AgNPs) was used as the matrix for MALDI MSI for the first time to simultaneously analyze 10 classes of lipids from the brain. This analysis included fatty acids and their derivatives, sterols, CPAs, LPA and PAs, LPE and PEs, LPC and PCs, PS, Cers, SMs, and MAGs and DAGs, and other small metabolites. Owing to the abundant silver ions on the surface of PVP-capped AgNPs, compounds with poor ionization efficiency such as FAs and sterols can be detected. The PVP-capped AgNPs based MALDI MSI analysis of mouse brain showed that lipid distributions in the substructures of the mouse brain can be connected with their biological functions. The brain lipids in rats with middle cerebral artery occlusion (MCAO) were also investigated. Most unsaturated FAs, prostaglandins, CPAs, vitamin A, neuraminic acid, 5-OH-tryptophan and the K+ adducts of most phospholipids (PAs, LPE, PEs, PCs, PS) and SMs were extremely down regulated in the ischemic region and saturated FA, Cers, hexanoylcarnitine, stearaldehyde, the Na+ adduct of phospholipids (LPA, PAs, LPE, PEs, LPC, PCs) and SMs were highly expressed in the damaged section. These novel findings could be very significant for elucidating the disease mechanism. MALDI MSI using PVP-capped AgNPs as a matrix can be a powerful tool in histopathology and pathology studies.

To enhance the stability in humidity is very crucial to hybrid organic-inorganic lead halide perovskites in a broad range of applications. This report describes a coating stratergy of perovskite nanocrystals via polymethylmethacrylate-introduced ligand-assisted reprecipitation, using the interactions between the Pb cations on the surface of perovskite nanocrystals and the functional ester carbonyl groups in polymethylmethacrylate framework. The hydrophobic framework shields the open metal sites of hybrid organic-inorganic lead halide perovskites from being attacked by water, effectively retarding the diffusion of water into the perovskite nanocrystals. The as-prepared films demonstrate high resistance to heat and moisture. Additionally, the introduction of polymethylmethacrylate into ligand-assisted reprecipitation can effectively control the bulk precipitation and promote the stability of the perovskite solution.

Bacterial infectious diseases, such as sepsis, can lead to impaired function in the lungs, kidneys, and other vital organs. Although established technologies have been designed for the extracorporeal removal of bacteria, a high flow velocity of the true bloodstream might result in low capture efficiency and prevent the realization of their full clinical potential. Here, we develop a dialyzer made by three-dimensional carbon foam pre-grafted with nanowires to isolate bacteria from unprocessed blood. The tip region of polycrystalline nanowires is bent readily to form three-dimensional nanoclaws when dragged by the molecular force of ligand-receptor, because of a decreasing Young’s moduli from the bottom to the tip. The bacterial capture efficiency was improved from ~10% on carbon foam and ~40% on unbendable single-crystalline nanowires/carbon foam to 97% on bendable polycrystalline nanowires/carbon foam in a fluid bloodstream of 10 cm s−1 velocity., Bacteria and other pathogens entering the blood stream can have serious consequences, which can even lead to death. Here, the authors developed a sieve containing nano-sized claws that capture and hold these intruders, thus aiding their removal from patient’s blood

Surface-enhanced spectroscopy (SES), including surface-enhanced Raman spectroscopy (SERS), surface-enhanced infrared absorption (SEIRA), surface-enhanced fluorescence (SEF), surface-enhanced hyper-Raman spectroscopy (SEHRS), surface-enhanced second harmonic generation (SESHG), and surface-enhanced electrochemiluminescence (SEECL), is an emerging subject that has received significant attention from the research community over the past 40 years. The confined and strong enhanced electromagnetic fields generated from the surface of noble metal nanostructures are considered as the main cause of SES. More importantly, it has been proven that SES is strongly related to the orientation and inter-nanoparticle coupling of different nanostructures. This review article mainly focuses on the application of ordered nanoparticle self-assemblies in SES. Different strategies for the fabrication of ordered nanoparticle self-assemblies, the mechanisms of SES, and the application of SES have been reviewed in detail.

This paper involves an exhaust gas waste heat recovery system for vehicles, which uses thermoelectric modules and a heat exchanger to produce electric power. Based on summarizing the latest research of vehicle exhaust thermo-electric generator (TEG), it presents two new fin structures for the cylindrical heat exchanger in a TEG system. It mainly studies the thermal performance of two kinds of three-dimensional cylindrical heat exchanger models including spiral-fin heat exchanger with variable pitch in a computational fluid dynamics simulation environment. In terms of interface temperature and thermal uniformity and based on an evaluation method of the temperature uniformity for the heat exchangers, the thermal characteristics of heat exchangers with different pitch angle of the twisted fins, pitch of spiral fin, fin thickness and fin height are discussed. Two new fin structures are feasible to enhance the heat transfer performance of heat exchanger.

For the first of time, we demonstrate that methylammonium cadmium halides show photoelectrochemical (PEC) response with excellent humidity and chemical resistance because the oxidation state of almost all cadmium compounds is +2. The photocurrent densities of two-dimensional (2D) layered (MA)2CdCl4 perovskites are about 0.30 mA cm−2 under 100 mW cm−2 irradiation. The interaction between these methylammonium cadmium halides and water vapor is studied by probing film morphology and characterizing single crystal structure. It is shown that H2O is able to complex with the perovskite, forming a hydrate product with the molecular formula of MACd3Cl7·3H2O upon humidity exposure. This causes a decrease in absorption and a recognizable change in the crystal structure of the material. When compared to methyl-ammonium lead iodide (MAPbI3), the PEC stability of 2D layered (MA)2CdCl4 perovskites with BQ/BQ˙− redox couples (where BQ is benzoquinone) in CH2Cl2 is enhanced from 50 hours to 600 hours, exhibiting an increase of 12 times.

Autoclaved aerated concrete waste (AACW) is an inorganic porous construction and demolition waste, which is possible to be environmentally used as an internal curing agent, due to its water absorption and release characteristics. In present work, fine aggregate (sand) was replaced by AACW aggregate with the same volume for internal curing purpose. The potential curing effect of AACW was also compared with a classical internal curing agent, i.e. expanded perlite (EPA), under the same particle size condition. Results indicate that the compressive strength of AACW groups after 28-day sealing curing is basically the same as that of the control group. Compared with EPA, internal curing with AACW can better improve the internal relative humidity, reduce the autogenous shrinkage, and delay the cracking time of cement mortar. At the same time, AACW effectively refines the pore structure and improves the micro-hardness of the interfacial transition zone (ITZ) through internal curing, and enhances the resistance to chloride penetration.

Background Inflammatory bowel disease (IBD) is an inflammatory response relative chronic disease in the intestinal tract. Our previous study demonstrated melatonin exerts an improvement effect on stress related IBD. The present study was further performed to clarify the mechanism of melatonin in dextran sodium sulfate (DSS)-induced colitis in mice. Methods We successfully established a DSS-induced colitis mouse model and hydrogen peroxide (H2O2)-treated intestinal epithelial cells (IECs) with or without melatonin supplementation to explore the improvement of melatonin in the DSS-induced colitis. Results Melatonin supplementation normalized the colitis, oxidative stress, mitochondria dysfunction, apoptosis and inflammation response, including the increase of intestinal permeability, histological score and the level of IL-1β, TNF-α, iNOS, NLRP3, MDA, Bax, Caspase3, Cytochrome C and Caspase9, as well as the reduction of body weight, colon length, Card9, IFN-γ, IL-10, T-AOC, Calpain1, Mfn2, VDAC1, RORα and SIRT1 proteins in DSS-treated mice. However, the improvement effects of melatonin were blocked by MT2 antagonist 4P-PDOT, PI3K antagonist LY294002, AKT antagonist GSK690693 and Nrf2 antagonist ML385, while mimicked by P65 antagonist PDTC in H2O2-IECs. Conclusion Melatonin-mediated MT2 activated PI3K/AKT/Nrf2/RORα/SIRT1 pathway and suppressed NF-κB pathway, ultimately improved DSS-induced colitis, which provides evidence for melatonin as an efficient therapy against oxidative stress associated IBD.

Fuel cell vehicles (FCVs) are becoming increasingly popular because they are both environmentally friendly and energy efficient. However, because no waste heat from the internal combustion engine can be used, the additional electricity needed to heat the cabin in cold weather increases the energy consumption substantially. This also lowers both the fuel economics and driving range. The required additional heating is typically done with a positive temperature coefficient (PTC) electric heater. To overcome the associated performance problem, a novel vehicle-integrated thermal management system (VTMS) with a heat-pump system is developed and investigated in this study. Using a simulation, the performance of the VTMS is investigated with respect to cooling performance, heating performance, and heating energy consumption for several different heat sources. For four different driving cycles, the equivalent hydrogen consumption (EHC) is highest when the PTC heater is used. The heat-pump system, which uses waste heat generated by a proton exchange membrane fuel cell, shows the lowest EHC. The results reveal that the use of a heat-pump heating system with waste heat can reduce hydrogen consumption by ∼14.6%, 6.5%, 16.9%, and 16.7% compared to PTC heating. Furthermore, the driving ranges increased by 17.2, 6.8, 20.3, and 12.6 km per 100 km, respectively. The VTMS, thanks to its ability to reduce energy consumption effectively, makes it possible to improve the thermal comfort in the vehicle cabin, which is especially useful for the commercialization of FCVs.

Graphene quantum dots (GQDs) have been widely used as fluorescence probes to detect metal ions with satisfactory selectivity. However, the diverse chemical structures of GQDs lead to selectivity for multiple metal ions, and this can lead to trouble in the interpretation of selectivity due to the lack of an in depth and systematic analysis. Herein, bare GQDs were synthesized by oxidizing carbon black with nitric acid and used as fluorescent probes to detect metal ions. We found that the specific ability of GQDs to recognize ferric ions relates to the acidity of the medium. Specifically, we demonstrated that the coordination between GQDs and Fe3+ is regulated by the pH of the aqueous GQDs solution. Dissociative Fe3+ can coordinate with the hydroxyl groups on the surface of the GQDs to form aggregates (such as iron hydroxide), which induces fluorescence quenching. A satisfactory selectivity for Fe3+ ions was achieved under relatively acidic conditions; this is because of the extremely small Ksp of ferric hyd...

Vehicle lightweighting has been considered as one of the most important solutions to improve fuel economy and reduce harmful emissions. Considering the PowerTrain System (PTS) lightweighting of a heavy-duty truck tractor, cast iron of which the transmission shell was made is replaced with aluminum. Such weight reduction caused the irrationality of the natural frequency matching and the vehicle NVH performance become worse. In order to evaluate the influence of PTS lightweighting on the vibration and noise, the theoretical analysis and experimental tests have been done. The Genetic Algorithm (GA) method was adopted for the Powertrain Mounting System (PMS) optimization. Considering the installation position of PMS, the limitations of package space, cost and available time, the mounting stiffness was chosen as the design variables. One combination of the main vibration energy distribution of PMS was selected as the objective function of optimization design. After optimization, the vehicle experimental study was carried out to investigate the vibration and noise performance of the PMS at idle and Whole Open Throttle (WOT). The test results show that the optimization of PMS had a significant improvement on the vehicle vibration and noise performance.

Optomechanical dark mode plays a central role in effective mechanically-mediated conversion of two different cavity fields. In this paper, we present a more efficient method to utilize the dark mode to transfer a coherent signal. When an auxiliary cavity mode is exploited, two approaches are proposed to effectively eliminate the optomechanical bright mode, and only the optomechanical dark mode is left to facilitate state transfer. Even with small cooperativity and different losses for the two target modes, the internal cavity mode-conversion efficiency can also reach unity.

Gastric cancer is a common cancer with a poor prognosis. Chemokines play important roles in the tumor microenvironments to support tumor growth and metastasis. The effects of C-C motif chemokine ligand 22 (CCL22) in gastric cancer remain unclear.Between January 1, 2014 and April 31, 2014, a total of 298 gastric cancer patients were recruited to this study. Circulating concentrations of CCL22 were measured in gastric cancer patients before surgery, at discharged and during follow-up visits. The expression of CCL22 in gastric cancer tumor beds was measured by immunohistochemistry. The proportion of CD3Gastric cancer patients had higher serum CCL22 levels compared to healthy controls (P 0.001). Immunohistochemistry indicated that the gastric cancer tumor beds were the source of serum CCL22, as gastric cancer patients had an increased proportion of strong expression of CCL22 (P 0.01), and immunohistochemistry scores were positively correlated with levels of circulating CCL22 (P 0.001). Gastric cancer tissue harbored a higher percentage of regulatory T cells compared to normal tumor-free stomach margins (P 0.001), and this abundance of regulatory T cells was positively correlated with circulating levels of CCL22 (P 0.001). Gastric cancer patients with peritoneal metastasis showed increased levels of circulating CCL22 before surgery compared to metastasis-free patients (P 0.001). Gastric cancer patients with the recurrence within the first year after surgery had elevated serum CCL22 concentrations at different time points compared to those of recurrence-free patients (P 0.001). Logistic regression analysis indicated that high CCL22 circulating levels before surgery is a risk factor for peritoneal metastasis and an independent risk factor for an early recurrence after surgery.CCL22 plays an important role in supporting gastric cancer development presumably by increasing the percentage of regulatory T cells in the tumor microenvironments. CCL22 levels in sera have a predictive value for gastric cancer peritoneal metastasis and the early recurrence. Therefore, CCL22 may be a therapeutic target for gastric cancer.

In the past, the progressive collapse resulting from local failures during accidents has caused many tragedies and loss of life. Although long-span spatial grid structures are characterised by a high degree of static indeterminacy, the sudden failure of key members may lead to a catastrophic progressive collapse. For this reason, it is especially necessary to research the progressive collapse resistance capacity of long-span spatial grid structures. This paper presents an evaluation method of important members and a novel dynamic analysis method for simulating the progressive collapse of long-span spatial grid structures. Engineering cases were analysed to validate these proposed method. These proposed methods were eventually implemented in the progressive collapse analysis of the main stadium for the Universiade Sports Center. The roof of the structure was concluded to have good resistance against progressive collapse. The novel methods provide results close to practice and are especially suitable for the progressive collapse analysis of long-span spatial grid structures.

In this work, we report the fabrication of hierarchical nanofiber bundles from a perylene monoimide molecule that enable the sensitive detection of various inert volatile organic compounds (VOCs). We demonstrate that the internanofiber spacing of the bundles with appropriate packing interactions can be effectively adjusted by various VOCs, which is in turn translated into the dynamic fluorescence responses. Upon further decreasing the size of the nanofiber bundles, of which the internanofiber spacing is more favorably adjusted, enhanced fluorescence responses to various VOC vapors can be achieved. Our work presents a new protocol, i.e., translating the stimuli-responsive internanofiber spacing into fluorescence responses, to construct novel fluorescence sensors for various hazardous chemical vapors.

Surface-enhanced Raman scattering (SERS) is expected as a technique that even theoretically detected chemicals at the single molecule level by surface plasmon phenomena of noble metal nanostructures. Insensitivity of detecting Raman weak-intensity molecules and low adsorptivity of gaseous molecules on solid substrates are two main factors hindering the application of SERS in gas detectors. In this manuscript, we demonstrated an operational SERS strategy to detect gaseous Raman weak-intensity aldehydes that have been considered as a biomarker of lung cancer for abnormal content was measured in volatile organic compounds (VOCs) of lung cancer patients. To enhance the adsorption of gaseous molecules, dendritic Ag nanocrystals mimicking the structural feature (dendritic) of moth's antennae were formed, wherein the existence of numerous cavity traps in Ag dendritic nanocrystals prolonged reaction time of the gaseous molecules on the surface of solid surface through the "cavity-vortex" effect. By the nucleophilic addition reaction with the Raman-active probe molecule p-aminothiophenol (4-ATP) pregrafted on dendritic Ag nanocrystals, the gaseous aldehyde molecules were sensitively captured to detect at the ppb (parts per billion) level. Additionally, the sensitivity of this operational SERS strategy to detection of lung cancer biomarkers was not affected by the humidity, which represented a great potential in fast, easy, cost-effective, and noninvasive recognition of lung malignancies.

Herein, we focus on the design and geometry diversities of two dimensional LDHs nanosheet building blocks from lamellar to hierarchical structures to understand mass transfer mechanisms and highlight the importance of geometry-induced effects to overcome the diffusion constraints in solid–liquid interfaces.

In a multiobjective particle swarm optimization algorithm, selection of the global best particle for each particle of the population from a set of Pareto optimal solutions has a significant impact on the convergence and diversity of solutions, especially when optimizing problems with a large number of objectives. In this paper, a new method is introduced for selecting the global best particle, which is minimum distance of point to line multiobjective particle swarm optimization (MDPL-MOPSO). Using the basic concept of minimum distance of point to line and objective, the global best particle among archive members can be selected. Different test functions were used to test and compare MDPL-MOPSO with CD-MOPSO. The result shows that the convergence and diversity of MDPL-MOPSO are relatively better than CD-MOPSO. Finally, the proposed multiobjective particle swarm optimization algorithm is used for the Pareto optimal design of a five-degree-of-freedom vehicle vibration model, which resulted in numerous effective trade-offs among conflicting objectives, including seat acceleration, front tire velocity, rear tire velocity, relative displacement between sprung mass and front tire, and relative displacement between sprung mass and rear tire. The superiority of this work is demonstrated by comparing the obtained results with the literature.