Tracheal sound-based apnea detection using hidden Markov model in sedated volunteers and post anesthesia care unit patients.

The current method of apnea detection based on tracheal sounds is limited in certain situations. In this work, the Hidden Markov Model (HMM) algorithm based on segmentation is used to classify the respiratory and non-respiratory states of tracheal sounds, to achieve the purpose of apnea detection. Three groups of tracheal sounds were used, including two groups of data collected in the laboratory and a group of patient data in the post anesthesia care unit (PACU). One was used for model training, and the others (laboratory test group and clinical test group) were used for testing and apnea detection. The trained HMMs were used to segment the tracheal sounds in laboratory test data and clinical test data. Apnea was detected according to the segmentation results and respiratory flow rate/pressure which was the reference signal in two test groups. The sensitivity, specificity, and accuracy were calculated. For the laboratory test data, apnea detection sensitivity, specificity, and accuracy were 96.9%, 95.5%, and 95.7%, respectively. For the clinical test data, apnea detection sensitivity, specificity, and accuracy were 83.1%, 99.0% and 98.6%. Apnea detection based on tracheal sound using HMM is accurate and reliable for sedated volunteers and patients in PACU.

Direct analysis of bromine and iodine in dried serum spots by laser ablation inductively coupled plasma mass spectrometry.

RATIONALE: Accurate quantitative analysis of bromine and iodine in serum is an important aspect of monitoring body condition, but the volatile loss of halogen in sample pretreatment is a troublesome problem. We present a validated and flexible high-throughput method for quantification of bromine and iodine in dried serum spots (DSS) using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and an external aqueous standard calibration curve. The influence of serum matrix and laser ablation (LA) conditions on the analysis of bromine and iodine in DSS was researched systematically. METHODS: Aqueous standards without matrix matching were used for calibration to analyze bromine and iodine in serum by LA-ICP-MS. 5-µL volumes of the aqueous standard solution and serum samples in 10 times diluted concentration were deposited on the PTFE paper to form dried standard calibration spots (DSCS) and DSS, of less than 2 mm in diameter. LA was performed using a focused Nd:YAG laser beam in raster lineal scan mode. RESULTS: The limits of detection (LODs) for bromine and iodine in DSS were 0.23 and 0.03 mg L-1 , respectively. The relative standard deviation (RSD) for this method was less than 10%. The samples were also detected with matrix matching calibration by ICP-MS. The accuracy of the method was verified by statistical analysis of these results from ICP-MS and LA-ICP-MS. The accuracy is satisfactory with recoveries ranging from 81.5% to 118%. CONCLUSIONS: A novel and simple approach for high-throughput screening of bromine and iodine in DSS has been established by LA-ICP-MS. Calibration could be achieved using an aqueous standard solution instead of a matrix-matching solution. The method allowed analysis of low-volume biological samples without derivatization and decreased the risk of contamination or loss.

Cascaded redundant convolutional encoder-decoder network improved apnea detection performance using tracheal sounds in post anesthesia care unit patients.

Objective. Methods of detecting apnea based on acoustic features can be prone to misdiagnosed and missed diagnoses due to the influence of noise. The aim of this paper is to improve the performance of apnea detection algorithms in the Post Anesthesia Care Unit (PACU) using a denoising method that processes tracheal sounds without the need for separate background noise.Approach. Tracheal sound data from laboratory subjects was collected using a microphone. Record a segment of clinical background noise and clean tracheal sound data to synthesize the noisy tracheal sound data according to a specified signal-to-noise ratio. Extract the frequency-domain features of the tracheal sounds using the Short Time Fourier Transform (STFT) and input the Cascaded Redundant Convolutional Encoder-Decoder network (CR-CED) network for training. Patients' tracheal sound data collected in the PACU were then fed into the CR-CED network as test data and inversely transformed by STFT to obtain denoised tracheal sounds. The apnea detection algorithm was used to detect the tracheal sound after denoising.Results. Apnea events were correctly detected 207 times and normal respiratory events 11,305 times using tracheal sounds denoised by the CR-CED network. The sensitivity and specificity of apnea detection were 88% and 98.6%, respectively.Significance. The apnea detection results of tracheal sounds after CR-CED network denoising in the PACU are accurate and reliable. Tracheal sound can be denoised using this approach without separate background noise. It effectively improves the applicability of the tracheal sound denoising method in the medical environment while ensuring its correctness.

[Clinical analysis of resection and dura skull base reconstruction of cranionasal communication tumor in 31 cases].

Objective:To explore the methods of resection, dura and skull base repair and reconstruction of cranionasal communication tumor. Methods:Data of 31 patients with cranionasal communication tumor who underwent dura and skull base reconstruction after tumor resection from 2018 to 2022 were collected. Follow-up lasted for 3 to 41 months. Results:A total of 31 patients were enrolled, including 20 males and 11 females. The ages ranged from 19 to 74 years, with a median age of 57 years old. There were 17 benign lesions（one case of hemangioma, one case of Rathke cyst, one case of squamous papilloma, one case of craniopharyngioma, two cases of meningocele, two cases of varus papilloma, two cases of meningioma of grade Ⅰ, three cases of schwannoma, four cases of pituitary tumor） and 14 malignant lesions（one case of osteosarcoma, one case of poorly differentiated carcinoma, two cases of varus papilloma malignancy, two cases of olfactory neuroblastoma, two cases of adenocarcinoma, two cases of adenoid cystic carcinoma, four cases of squamous cell carcinoma） . Sixteen cases underwent nasal endoscopy combined with craniofacial incision and 15 cases underwent nasal endoscopy surgery alone. Complete resection of the mass and dura and skull base reconstruction were performed in all 31 patients, and free graft repair was performed in 8 cases（fascia lata in 5 cases and nasal mucosa in 3 cases）. Twenty-three cases were repaired with pedicled flaps（septal mucosal flap alone in 11 cases, septal mucosal flap combined with free graft in 6 cases, and cap aponeurosis combined with free graft in 6 cases）. Eight out of 31 patients underwent skull base bone repair. Postoperative cerebral hemorrhage occurred in 1 case, cerebrospinal fluid leakage in 1 case, intracranial infection in 2 cases. All patients were successfully treated without severe sequelae. Cerebrospinal fluid leakage and intracranial infection occurred in one patient after radiotherapy, who recovered after conservative treatment. All 17 patients with benign lesions survived. Thirteen out of 14 patients with malignant lesions received radiotherapy after surgery, nine survived without recurrence, five cases recurred, of which 2 survived with tumor, one underwent reoperation and 2 died. Conclusion:Cranionasal communication tumors are high-risk diseases of anterior and middle skull base, and various surgical repair methods could be selected after complete resection of the tumor. Successful reconstruction and multidisciplinary cooperation are crucial for treatment outcome.

catena-Poly[[[aqua-copper(II)]-bis-[µ-N,N'-bis-(pyridin-4-yl)isophthalamide]-[aqua-copper(II)]-di-µ-sulfato] dimethyl-formamide disolvate].

In the title coordination polymer, {[Cu(SO4)(C18H14N4O2)(H2O)]·C3H7NO} n , the Cu(II) ion is coordinated by two N atoms of two briding N,N'-bis-(pyridin-4-yl)isophthalamide ligands, two O atoms of two bridging SO4(2-) anions and a water mol-ecule, giving a distorted CuN2O3 square-pyramidal geometry. The whole repeating mol-ecular unit is generated by inversion symmetry. This leads to the formation of a looped-chain one-dimensional coordination polymer propagating along [110]. The dimethyl-formamide (DMF) mol-ecules are linked to the chains via O-H⋯O hydrogen bonds. The chains are linked via N-H⋯O hydrogen bonds, forming two-dimensional networks parallel to (001). There are also a number of C-H⋯O inter-actions present and a parallel slipped π-π inter-action. The latter involves inversion-related pyridine rings with a centroid-centroid distance of 3.594 (2) Š[normal distance = 3.3338 (13) and slippage = 1.341 Å]. These inter-actions lead to the formation of a three-dimensional structure.

Differential proteomics analysis of female and male adults of Angiostrongylus cantonensis.

In this study, we identified the differentially expressed proteins of female and male adults of Angiostrongylus cantonensis through differential proteomics. We extracted and purified total proteins from male and female adults, separated proteins by two-dimensional difference gel electrophoresis (2D-DIGE) in pH 4-7, analyzed the gel images by DeCyder 7.0 software, and sacrificed the infected rats to count the number of male and female adults. It was found 28 protein spots that were differentially expressed; seven protein spots were then identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Five proteins were up-regulated and two proteins down-regulated in male adults compared with female adults. Three of the five up-regulated proteins with known functions ascribed to them were identified as galectin-1, proteasome alpha subunit and peroxiredoxin. The two down-regulated proteins were identified as indoleamine dioxygenase like-myoglobin and galectin. Furthermore, the female was significantly greater than male adults (P<0.01) in the rats. The findings demonstrate the differences in protein expression profiles and the ability to survive in the final host between female and male adults of A. cantonensis, and may provide a theoretical basis to study their developmental biology further.

[Eutrophication of water bodies and pollutions of microcystins in water and sediments in X County in the Huai River Basin].

OBJECTIVE: The purpose of the study is to investigate the status of eutrophication, the polluted situation of algae and microcystins in different water bodies of X County in the Huai River Basin. METHOD: Superficial water and sediment samples were taken from S River, Y River and a representative ditch in May 2010 (median-water period) and August (high water period ). Chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), chlorophyll a (Chl a) and algal density were detected by the recommended methods of national standard microcystin-LF/LR/LW/RR/YR in water (dissolved form), algal cells and sediments were detected by solid phase extraction and HPLC. RESULTS: Water pollutions in rivers and ditches of X County were serious, and total nitrogen and total phosphorus significantly exceed to the national standard for surface water quality. Most indexes of the water quality ranged from grade III to worse than grade V of national standard. Total nitrogen (4.78 mg/L) was most serious pollutions in the mainstream of S river, the water quality in high water period was better than in median-water period (P < 0.05). However, water quality in inner river Y and ditch in high water period was worse than in median-water period. Maximum chlorophyll a in ditch water reached 648.4 mg/ m3. The percent of cyanobacteria in various water bodies was less than 10% in median-water period, increased sharply to 40% and became dominant species in high water period. The maximum percentage of cyanobacteria was 44% in ditch. Microcystin-RR was the main toxin detected in water (dissolved form), algal cells and sediments. Maximum MC-RR in water and sediments reached 17.731 microg/L and 0.802 microg/g, respectively. The detected frequencies and concentrations of MC-LF/LR/LW/YR in most samples were low. CONCLUSION: Water bodies in X County were between middle eutrophication and hyper-eutrophication. Microcystin-RR of sediments in high water period were significant higher than in median-water period (P < 0.05).

Effects of sunlight exclusion on the profiles of monoterpene biosynthesis and accumulation in grape exocarp and mesocarp.

Terpenes are important aroma compounds in table Muscat grape and wine, and their content in the berry can be affected by sunlight. The effects of sunlight exclusion on monoterpene profiles and relevant gene expression profiles in the exocarp and mesocarp of table Muscat grape 'Jingxiangyu' at different development stages were thoroughly surveyed by bagging pre-veraison clusters in special opaque boxes. The responses of monoterpenes to sunlight treatments varied in three types, representatively linalool, ocimene and geraniol. Linalool was the most sensitive compound to sunlight, whose biosynthesis was severely inhibited by sunlight exclusion and then was elevated by re-exposure. Ocimene and glycosylated geraniol showed a certain suppressive and stimulative responses to sunlight exclusion respectively. Further transcription analysis revealed that VvPNLinNer1, VvCSbOci, VvGT7 and VvGT14 genes were mainly responsible for monoterpene accumulation and sensitivity to sunlight. VvDXS2 and VvDXR genes were partially related to the differential accumulation of total terpenes under different sunlight treatments.

Self-rectifying performance in the sandwiched structure of Ag/In-Ga-Zn-O/Pt bipolar resistive switching memory.

We reported that the resistive switching of Ag/In-Ga-Zn-O/Pt cells exhibited self-rectifying performance at low-resistance state (LRS). The self-rectifying behavior with reliability was dynamic at elevated temperature from 303 to 393 K. The Schottky barrier originated from the interface between Ag electrode and In-Ga-Zn-O films, identified by replacing Ag electrode with Cu and Ti metals. The reverse current at 1.2 V of LRS is strongly suppressed and more than three orders of magnitude lower than the forward current. The Schottky barrier height was calculated as approximately 0.32 eV, and the electron injection process and resistive switching mechanism were discussed.

In vitro study of the effects of Angiostrongylus cantonensis larvae extracts on apoptosis and dysfunction in the blood-brain barrier (BBB).

It has been hypothesized that blood-brain barrier (BBB) dysfunction in Angiostrongylus cantonensis infection might be due to the apoptosis of the hosts' BBB cells. Here, we evaluated this hypothesis through several methods, all based on an in vitro mouse BBB model consisting of primary culture brain microvascular endothelial cells (BMECs) and brain astrocytic cells (BACs). In the present study, a four-hour percolation and HRP permeability experiment showed that A. cantonensis larvae extracts can increase the permeability of the BBB. Apoptosis among BMECs and BACs after exposure to larvae extracts was monitored by TUNEL and annexin-V-FITC/PI double staining. A. cantonensis larvae extracts were found to induce apoptosis in both BMECs and BACs. For this reason, we concluded that the induction of apoptosis might participate in the BBB dysfunction observed during angiostrongyliasis. Improved fundamental understanding of how A. cantonensis induces apoptosis may lead to new approaches to the treatment or prevention of this parasitic disease.

Crystal structures and magnetism of infinite alternating chains arranged by paddle-wheel dinuclear copper and mononuclear copper units.

The crystal structures and magnetic properties of two novel polyclusters {[Cu(3)(tci)(2)(H(2)O)(2)]·12H(2)O}(n) (1) and {[Cu(3)(tci)(2)(H(2)O)(2)]·6H(2)O}(n) (2) (tci = tris(2-carboxyethyl) isocyanurate) are investigated. The X-ray crystallographic analysis reveals that they contain interesting infinite alternating chains of dinuclear paddle-wheel copper and mononuclear copper units arranged in ABBA magnetism exchange mode. Variable-temperature magnetic susceptibility measurements on the two polyclusters show strong antiferromagnetism couplings between copper ions with exchange interactions J = -181.4 cm(-1), zj' = -0.31 cm(-1) for 1, J = -170 cm(-1), zj' = -0.42 cm(-1) for 2. With the aim of studying magneto-structural correlation, we synthesized a three-dimensional polymer [Cu(3)(tci)(2)(py)(4)(H(2)O)(2)](n) (3) based on isolated dinuclear cluster and mononuclear copper units. Fitting the susceptibility data yielded J = -176.1 cm(-1), zj' = -0.084 cm(-1) for 3.

Studies on cage-type tetranuclear metal clusters with ferrocenylphosphonate ligands.

Reaction of FcCH(2)PO(3)H(2) [Fc=(eta(5)-C(5)H(5))Fe(eta(5)-C(5)H(4))] (H(2)FMPA) and 1,10-phenanthroline (phen) with Cd(OAc)(2).2 H(2)O or ZnSO(4).7 H(2)O in methanol in the presence of triethylamine resulted in the formation of two new ferrocenylphosphonate metal-cage complexes [M(4)(fmpa)(4)(phen)(4)] 7 CH(3)OH (M=Cd 1, M=Zn 2). Both structures contain two kinds of isomeric tetranuclear metal phosphonate cages, which are linked to one another by pi-pi interactions between the phen molecules. In 1, the Cd1, Cd3, and Cd4 atoms are all pentacoordinate, while the Cd2 atom is coordinated by four oxygen atoms from three phosphonate ligands and two nitrogen atoms from the chelating phen in a distorted octahedral geometry. Four Cd atoms from each unit are interconnected through bridging phosphonate ligands with different coordination modes, such as 5.221, 4.211, and 2.11 (Harris notation), yielding a {Cd(4)} cage. In 2, each Zn atom is coordinated by three oxygen atoms from three phosphonate ligands and two nitrogen atoms from phen, leading to a distorted square-pyramidal geometry. The four Zn atoms of each isomeric unit are also interconnected through four bridging phosphonate ligands to yield a {Zn(4)} cage. Fluorescent studies indicate that ligand-to-ligand charge-transfer photoluminescence is observed for 1, while the emission bands of 2 can be assigned to an admixture of ligand-to-ligand and metal-to-ligand charge transfer. Solution-state differential pulse voltammetry indicates that the half-wave potentials of the ferrocenyl moieties in 1 and 2 have different deviations relative to the relevant H(2)FMPA ligand. This may be because the highest occupied molecular orbital (HOMO) in 1 is located in the FMPA(2-) groups, while in 2 the HOMO is located in the phen and Zn(II) groups, so the Fe(II) centers in complex 1 are more easily oxidized to Fe(III) centers than those of 2. The third-order nonlinear optical (NLO) measurements show that both 1 and 2 exhibit strong third-order NLO self-focusing effects; hence, they are promising candidates for NLO materials. By calculating the component of the lowest unoccupied molecular orbitals of 1 and 2, we confirmed that the co-planar phen rings control their optical nonlinearity, while the H(2)FMPA ligands and metal ions have only a weak influence on their NLO properties.