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The goal of this study was to investigate the value of the long-term average spectrum in the acoustic analysis of snore sounds arising from different sources in the upper airway.Long-term average spectrum was used to analyze sequences of 10 consecutive snore sounds that had been divided into 2 groups, soft-palate type and lateral-wall type, according to the vibration site generating the snore sounds and the patterns of soft tissue collapse in the upper airway as identified by drug-induced sleep endoscopy. We calculated the first spectral peak, mean spectral energy, high-frequency energy, 0-1 kHz spectral energy, 1-5 kHz spectral energy, and 0-1 kHz/1-5 kHz difference from each group and compared the differences between them.All parameters except mean spectral energy showed significant differences between the 2 groups. The first spectral peak of less than 265.53 Hz, and the 0-1k/1-5 kHz difference of less than -11.6 dB strongly suggests soft-palate-type snore sounds.Long-term average spectrum has potential application for snore sound source identification. We recommend using first spectral peak and a 0-1 kHz/1-5 Hz difference to identify soft-palate-type snore sounds.Peng H, Xu H, Xu Z, Jia R, Yu H. Long-term average spectrum measures of consecutive snore sounds from different sources determined by drug-induced sleep endoscopy.

An asymmetrical architecture is developed to discriminate monosaccharide enantiomers based on enzyme-like cascade reactions in homochiral CuMOF pockets. The increased enzyme-like activity under LSPR excitation enhanced the identification performance.

The high cost and easy denaturation of natural enzymes under environmental conditions hinder their practical usefulness in sensing devices. In this study, peroxidase (POD)-like metal-organic frameworks (MOFs) were in situ grown in the nanochannels of an anodized TiO2 membrane (TiO2NM) as an electrochemical platform for multitarget sensing. By directly using a nanochannel wall as the precursor of metal nodes, Ti-MOFs were in situ derived on the nanochannel wall. Benefitting from the presence of bipyridine groups on the ligands, the MOFs in the nanochannels provide plenty of sites for Fe3+ anchoring, thus endowing the resulting membrane (named as Fe3+:MOFs/TiO2NM) with remarkable POD-like activity. Such Fe3+-induced POD-like activity is very sensitive to thiol-containing molecules owing to the strong coordination effect of thiols on Fe3+. Most importantly, the POD-like activity of nanochannels can be in situ characterized by the current-potential (I-V) properties via catalyzing the oxidation of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) substrate to the corresponding positively charged product ABTS•+. As a proof-of-concept application, the free-standing POD-like membranes were applied as a label-free assay in sensing cysteine, as well as monitoring acetylcholinesterase (AChE) activity through the generated thiol-containing product. Furthermore, based on the toxicity effect of organophosphorus (OP) compounds on AChE, the robust membranes were successfully utilized to evaluate the toxicity of diverse OP compounds. The POD-like nanochannels open up an innovative way to expand the application of nanochannel-based electrochemical sensing platforms in drug inspection, food safety, and environmental pollution.

It is important to detect cancer biomarkers at an early stage of tumor development for the effective diagnosis and treatment of cancer. As a well-known probe for detecting superoxide (·O

As an intriguing and intrinsic feature of life, chirality is highly associated with many significant biological processes. Simultaneous recognition and quantification of enantiomers remains a major challenge. Here, a sensitive enantiomer identification device is developed on TiO

Background Snoring source analysis is essential for an appropriate surgical decision for both simple snorers and obstructive sleep apnea/hypopnea syndrome (OSAHS) patients. Objective As snoring sounds carry significant information about tissue vibrations within the upper airway, a new feature entitled compressed histogram of oriented gradients (CHOG) is proposed to recognize vibration patterns of the snoring source acoustically by compressing histogram of oriented gradients (HOG) descriptors via the multilinear principal component analysis (MPCA) algorithm. Methods Each vibration pattern corresponds to a sole or combinatorial vibration among the four upper airway soft tissues of soft palate, lateral pharyngeal wall, tongue base, and epiglottis. 1037 snoring events from noncontact sound recordings of 76 simple snorers or OSAHS patients during drug-induced sleep endoscopy (DISE) were evaluated. Results With a support vector machine (SVM) as the classifier, the proposed CHOG achieved a recognition accuracy of 89.8% for the seven observable vibration patterns of the snoring source categorized in our most recent work. Conclusion The CHOG outperforms other single features widely used for acoustic analysis of sole vibration site.

The high cost and easy denaturation of natural enzymes under environmental conditions hinder their practical usefulness in sensing devices. In this study, peroxidase (POD)-like metal-organic frameworks (MOFs) were

The level of hydrogen sulfide in the brain and vasculature has long been associated with human health and diseases. Hence, simple and robust analytical tools allowing determination of hydrogen sulfide levels are highly desirable. In this work, a biomineralization-driven ion gate in TiO2 nanochannel arrays for H2S sensing was designed and developed. The formed CuS precipitation decreased the transmembrane current in the presence of bovine serum albumin used as biological mineralizer. Label-free assay for sensing of intracellular S2- was achieved based on changes in ionic current with a detection limit of 56 MCF-7 cells. More importantly, the proposed sensing strategy was promising for reusable application through dissolution of CuS in an acidic media (pH = 1).

Au nanoparticles were asymmetrically fabricated at one tip of TiO2 nanochannels by combining a photocatalytic reaction and limited penetration of light. Using the asymmetrical nanochannel-based membrane as a plasma absorber, near-infrared-gated artificial ionic nanochannels were designed.

Today, the internet of things (IoT) has become an inevitable trend in the development and integration of communication and information technology. The rapid increase of IoT terminals has led to scarcity of spectrum resources. Therefore, if cognitive radio (CR) technology can be added to IoT, it is bound to better meet the frequency requirements of the development of the IoT. In order to solve this problem, this paper uses unmanned aerial vehicles (UAVs) to access cognitive spectrum holes with CR in interweave cognitive IoT network. In the satellite coverage area, the UAV's GPS signal will be stronger. Therefore, this paper comprehensively considers the spectrum hole quality, UAV power limitation and satellite coverage issues, and proposes a spectrum allocation algorithm, which preferentially selects channels with high communication quality, and comprehensively considers UAV power control when implementing the algorithm. Simulation results show that the algorithm improves communication quality and spectrum allocation and realizes power control.

As cancer nanotherapeutics, the ideal multifunctional nanoparticles not only have the processing ability to accumulate effectively in tumors, but also can be excreted rapidly from the body via renal clearance after effective treatment. Melanin is an endogenous biological material, and gelatin has natural biocompatibility and biodegradability. Such materials are more promising in the development of diagnostic and therapeutic nanoplatform for future clinical translation. In this study, we have developed a kind of size-shrinkable PA/MRI theranostic agent based on gelatin fabricated ultrasmall melanin nanoparticles (MNPs-GNP). The MNPs-GNP nanoparticles, with a size of about 100 nm, presented good dispersibility, broadband light absorbance, negligible cellular cytotoxicity, preferable tumor accumulation by EPR-based passive targeting. The dual-modal imaging results showed that the nanoparticles have excellent photoacoustic (PA) imaging and nuclear magnetic resonance (MRI) imaging after tumor-bearing mice were intravenously injected with MNPs-GNP. Additionally, gelatin is the substrate of matrix metalloproteinase-2 (MMP-2), following with the degradation of gelatin nanoparticles by MMP-2, the large-size MNPs-GNP turns to be small-size melanin, which could mainly be excreted via renal clearance avoiding potential toxicity to body tissues. These preliminary results indicated that MNPs-GNP can overcome the dilemma between EPR and renal clearance, which has clinical application potentiality as a PA/MRI dual-modal candidate agent for cancer theranostics.

By virtue of their large surface area, extensive charge delocalization, good conductivity, and high mass transfer efficiency, heteroatom-doped hierarchically porous carbons are ideal micro/nano reactors or catalysts for various electrochemical processes. Bovine blood plasma, a major by-product of the food industry, contains abundant organic–inorganic composites (e.g., bovine serum albumin and NaCl). We have prepared several biocarbons with different doping states and porosities by pyrolysis of the organic–inorganic aggregates in blood plasma in the presence of alkali or alkaline earth metal (AM) salts. In the case of AM = Ca, synergistic effects associated with molten NaCl etching and pyrolysis-generated CaO/CaClOH templates lead to porous carbons (denoted as PC-Ca/Na) having multimodal pores and high nitrogen concentrations. As a result, PC-Ca/Na proves to be an excellent carbon-based metal-free electrocatalyst with a remarkable positive half-wave potential of 0.88 V, and a negative shift of only 3 mV after 10,000 potential cycles. Zn–air batteries fabricated by using PC-Ca/Na exhibit a peak power density of 152 mW cm–2 at a current density of 242 mA cm−2, outperforming a benchmark Pt/C catalyst. The multimodal-pore formation strategy developed in this work offers an effective approach to make full use of biowaste to fabricate high-performance device materials.

The advent of 'Big Data' and 'Deep Learning' offers both, a great challenge and a huge opportunity for personalised health-care. In machine learning-based biomedical data analysis, feature extraction is a key step for 'feeding' the subsequent classifiers. With increasing numbers of biomedical data, extracting features from these 'big' data is an intensive and time-consuming task. In this case study, we employ a Graphics Processing Unit (GPU) via Python to extract features from a large corpus of snore sound data. Those features can subsequently be imported into many well-known deep learning training frameworks without any format processing. The snore sound data were collected from several hospitals (20 subjects, with 770-990 MB per subject - in total 17.20 GB). Experimental results show that our GPU-based processing significantly speeds up the feature extraction phase, by up to seven times, as compared to the previous CPU system.

To discuss the possibility of fundamental frequency (F0) and formant frequency (FF) to generally differentiate the sources of snoring sounds determined by drug-induced sleep endoscopy (DISE).A total of 74 snoring subjects underwent DISE and snoring sounds were recorded simultaneously. The noise-suppressed snoring sounds were analyzed and classified into different groups based on the sources of vibration identified by DISE. F0 and FFs were calculated.Totally, 516 snoring sounds from three vibrating sources (the palate, combined the palate and the lateral wall, the lateral wall) of 47 patients were divided into three groups then analyzed. The levels of F0 and FFs for each group follow the order: Group 1 Group 2 Group 3. There was statistical difference between Group 1 and other groups in F0 and F2 (p .05). The area under the receiver-operator curves (AUC) was F0, at 0.727, and the cut-off value was 134.2 Hz; and F2, at 0.654, and the cut-off value was 2028.0 Hz.F0 and the second formant frequency (F2) are found to be significantly lower in palatal snoring sound. F0 might be a significant in distinguishing palatal snoring sound from non-palatal snoring sound. F2 is more significant than F1 and F3 in identifying the sources of the snoring sounds but is less sensitive than F0.

Au nanoparticles were asymmetrically fabricated at one tip of TiO2 nanochannels by combining a photocatalytic reaction and limited penetration of light. Using the asymmetrical nanochannel-based membrane as a plasma absorber, near-infrared-gated artificial ionic nanochannels were designed.

Among natural energy resources, methane clathrate has attracted tremendous attention because of its strong relevance to current energy and environment issues. Yet little is known about how the clathrate starts to nucleate and disintegrate at the molecular level, because such microscopic processes are difficult to probe experimentally. Using surface-specific sum-frequency vibrational spectroscopy, we have studied in situ the nucleation and disintegration of methane clathrate embryos at the methane-gas–water interface under high pressure and different temperatures. Before appearance of macroscopic methane clathrate, the interfacial structure undergoes 3 stages as temperature varies, namely, dissolution of methane molecules into water interface, formation of cage-like methane–water complexes, and appearance of microscopic methane clathrate, while the bulk water structure remains unchanged. We find spectral features associated with methane–water complexes emerging in the induction time. The complexes are present over a wide temperature window and act as nuclei for clathrate growth. Their existence in the melt of clathrates explains why melted clathrates can be more readily recrystallized at higher temperature, the so-called “memory effect.” Our findings here on the nucleation mechanism of clathrates could provide guidance for rational control of formation and disintegration of clathrates.

The level of hydrogen sulfide in the brain and vasculature has long been associated with human health and diseases. Hence, simple and robust analytical tools allowing determination of hydrogen sulfide levels are highly desirable. In this work, a biomineralization-driven ion gate in TiO

Innovation service network is the inevitable result of the collaborative cooperation of innovation service subjects, and also an important strategic resource for innovation activities in emerging industries. The research of innovation service network has important decision reference value for the promotion of collaborative service capability for the innovation demand of emerging industries. By analyzing the evolution process and law of innovation service network in emerging industries, improving the main line around the ability of collaborative service, combining the evolution stage of innovation service network, the complexity of innovation demand and the integration of service resources, this paper focuses on designing the upgrade path of innovation service network based on key nodes, the path of innovation service network upgrade based on service chain integration, and the upgrade path of innovation service network based on core network coordination, in order to optimize the structure of innovation service network of emerging industries and improve its ability of collaborative service provides theoretical guidance, which is of great practical significance to support the innovation and development of emerging industries.

The aim of the work is to design lightweight thermal insulation mortar with function of improved thermal characteristics using glazed hollow beads and micro-encapsulated phase change materials (PCM). Various experimental methods are carried out to investigate the effect on physical, mechanical, thermal characteristics and air void distribution of different compositions and mix. The results show that the mortar composition has a significant effect on its physical, mechanical and thermal characteristics. Thermal conductivity and thermal effusivity decrease with increasing PCM content. Thermal characteristic tests using room device indicated that the room device prepared with PCM board can reduce both the maximum indoor center temperature and temperature fluctuations, and this effect becomes more significant as the PCM content increases. Meanwhile, high PCM content will increase the average air void size, which will increase the air void content of the mortar specimen significantly.

A rumor spreading model for the web forums based on the heterogeneity of the web forum user behaviors and SEIR model is proposed in this paper. First, according to the meanfield equations of the model on inhomogeneous networks, the critical threshold of the spreading of rumor is deduced; Then the simulation and numerical analysis of the model itself and the influences of trust mechanism to the model are given, which verify the validity of the model and the introduction of trust mechanism can effectively reduce the rumor influence, the velocity of rumor spreading and the rumor size; Finally, combined with the previous conclusions and the high-influence limited trust relationships between the web forum users, a high-influence immunization algorithm is given. The experimental results show that the algorithm able to reach better effect than traditional immunization algorithm.

Protein kinases are general and significant regulators in the cell signaling pathway, and it is still greatly desired to achieve simple and quick kinase detection. Herein, we develop a simple and sensitive photoelectrochemical strategy for the detection of protein kinase activity based on the bond between phosphorylated peptide and phosphorylated graphite-like carbon nitride (P-g-C3N4) conjugates triggered by Zr(4+) ion coordination. Under optimal conditions, the increased photocurrent is proportional to the protein kinase A (PKA) concentration ranging from 0.05 to 50 U/mL with a detection limit of 0.077 U/mL. Moreover, this photoelectrochemical assay can be also applied to quantitative analysis of kinase inhibition. The results indicated that the IC50 value (inhibitor concentration producing 50% inhibitor) for ellagic acid was 9.1 μM. Moreover, the developed method is further applied to detect PKA activity in real samples, which contains serum from healthy person and gastric cancer patients and breast tissue from healthy person and breast cancer patients. Therefore, the established protocol provides a new and simple tool for assay of kinase activity and its inhibitors with low cost and high sensitivity.

In this study, novel green lightweight foamed geopolymer concretes (LFGC) aerated using hydrogen peroxide based on fly ash, metakaolin and expanded polystyrene (EPS) particles was developed for thermal insulation materials. Physical properties, mechanical strength, thermal characteristics and permeability of LFGC were evaluated by designing and optimizing the components of EPS particles, hydrogen peroxide, metakaolin and fly ash. Meanwhile, the internal microstructure was also investigated by pore structure and scanning electron microscope. The results show that as the content of EPS particles and hydrogen peroxide increased, the compressive strength of LFGC decreased by 57.6% and 9.7%, respectively. The lightweight and thermal insulation properties are enhanced as the EPS particles and hydrogen peroxide content increase due to the contribution of low-density EPS particles and closed foamed air voids. The LFGC presented its dry density range of 300–650 kg/m3, the compressive strength between 2.0 and 5.5 MPa and the thermal conductivity between 0.122 and 0.195 W/m∙K, showing better mechanical strength than the traditional ordinary cement foamed concrete with the same density. Meanwhile, the microstructure also shows that the EPS particles have good compatibility with the foamed geopolymer pastes.

Three types of polymer modifier used in concrete (styrene-butadiene rubber latex, polyacrylic ester emulsion and organic silicon waterproof agent) were employed to investigate their effects on the compressive strength, capillary water absorption and chloride ion permeability of concrete. Results show that the incorporation of polymer modifier reduces the compressive strength, and fly ash (FA) can improve this adverse effect. All three polymer modifiers can significantly reduce the permeability of concrete, and the effect is more significant at high water-to-binder ratio. Among them, the compressive strength of organic silicon waterproof agent modified concrete is the most similar to that of ordinary concrete, and the sorptivity coefficient is relatively low, even at higher dosages. In addition, with the prolongation of the curing age, the impermeability of polymer-modified concrete mixed with FA reaches the best. The addition of FA can not only achieve economic and environmental benefits, but also cooperate with the polymer in the concrete, thereby improving the waterproofness of the concrete.

Snore related signals (SRS) have been found to carry important information about the snore source and obstruction site in the upper airway of an Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS) patient. An overnight audio recording of an individual subject is the preliminary and essential material for further study and diagnosis. Automatic detection, segmentation and classification of SRS from overnight audio recordings are significant in establishing a personal health database and in researching the area on a large scale. In this study, the authors focused on how to implement this intelligent method by combining acoustic signal processing with machine learning techniques. The authors proposed a systematic solution includes SRS events detection, classifier training, automatic segmentation and classification. An overnight audio recording of a severe OSAHS patient is taken as an example to demonstrate the feasibility of their method. Both the experimental data testing and subjective testing of 25 volunteers (17 males and 8 females) demonstrated that their method could be effective in automatic detection, segmentation and classification of the SRS from original audio recordings.

Sum-frequency vibrational spectroscopy in the CH and OH stretch region was used to study ethanol adsorption on fused silica from vapor of different ethanol partial pressures. It was found that the adsorbed ethanol molecules were oriented with their methyl group tilted away from the surface normal by an average angle of similar to 45 degrees at low ethanol vapor pressures and similar to 39 degrees when approaching saturated vapor pressure. The spectral change with ethanol vapor pressure and the deduced adsorption isotherm show that ethanol molecules have two distinct adsorption sites on silica: One is the silanol group site to which an ethanol molecule can be strongly hydrogen-bonded, and the other is the siloxane (Si-O-Si) group site to which an ethanol molecule can be weakly bonded. The presence of water in vapor significantly reduced the surface coverage of ethanol on silica due to competitive adsorption between ethanol and water.

Objective: To investigate the source of snoring sound in patients with simple snoring (SS) and different degrees of obstructive sleep apnea syndrome (OSAS) in order to provide a basis for the surgical treatment of snoring. Methods: Fifty-two patients with either SS or OSAS (with an apnea-hypopnea index ≤40) underwent drug-induced sleep nasendoscopy (DISN). Vibration sites in the pharyngeal cavity were observed. Results: Vibration of the soft palate, pharyngeal lateral wall, epiglottis, and tongue base appeared in 100, 53.8, 42.3, and 26.9% of the patients, respectively. The source of snoring sound was divided into two types: palatal fluttering only (type I) and multisite vibration (type II). The latter was divided into 3 subtypes: palatal fluttering with epiglottis vibration (type IIa), palatal fluttering with lateral wall vibration (type IIb), and palatal fluttering with vibration of the lateral wall, epiglottis, and tongue base together (type IIc). The distribution of type I snoring was the highest in SS patients. Type IIb was more common in patients with medium and severe OSAS. Type IIc was most common in patients with severe OSAS. Conclusion: The source of snoring sound is diverse, with SS and OSAS patients showing different features. DISN is a very effective method of identifying the snoring source.