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1.
Small ; 20(15): e2308194, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38009488

ABSTRACT

Passive heating textiles (PHTs) have drawn increasing attention due to the advantages of energy-conservation heating. However, the heating capabilities of current PHTs are typically static and non-tunable, presenting poor adaptation to dynamic winter. Herein, a novel Janus textile with tunable heating modes is developed by constructing a customized structure with asymmetric optical properties. This Janus textile is created by coating one side of a cotton fabric with silver nanowires (AgNWs) and then applying transition metal carbides/nitrides (MXene) to the other side. The MXene side exhibits high solar absorptivity and low mid-infrared emissivity, while the AgNWs side has moderate solar absorptivity and mid-infrared emissivity. This structure ensures that the solar and radiative heating temperatures of the MXene side are 16 °C and 1.7 °C higher than those of the AgNWs side. This distinction allows for on-demand, accurate adjustments in solar and radiative heating capabilities by flipping the textile according to ambient temperature. Furthermore, this innovative design also features desired electric heating, thermal camouflage, self-cleaning and antibacterial properties, electromagnetic interference shielding, durability, and wearability. The Janus textile enables precise thermoregulation of the human body to adapt to variable cold weather, making it essential for optimal personal thermal management and climate change mitigation.

2.
Langmuir ; 40(17): 9215-9223, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38635343

ABSTRACT

Designing and developing high-performance shielding materials against electromagnetic interference is of utmost importance due to the rapid advancement of wireless telecommunication technologies. Such materials hold both fundamental and technological significance. A three-stage process is presented for creating ultralight, flexible aerogels from biomass to shield against electromagnetic interference. Collagen fibers sourced from leather solid waste are used for: (i) freeze-drying preparation of collagen fibers/poly(vinyl alcohol) (PVA) aerogels, (ii) adsorption of silver nanowires (AgNWs) onto collagen fiber/PVA aerogels, and (iii) Hydrophobic modification of collagen fiber/PVA/AgNWs aerogels with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (POTS). Scanning electron microscopy studies reveal that an interweaving of AgNWs and collagen fiber/PVA porous network has formed a conductive network, exhibiting an electrical conductivity of 103 S·m-1. The electromagnetic interference shielding effectiveness reached more than 62 dB, while the density was merely 5.8 mg/cm3. The collagen fiber/PVA/AgNWs/POTS aerogel displayed an even better electromagnetic shielding efficiency of 73 dB and water contact angle of 147°. The study results emphasize the distinctive capacity of leather solid waste to generate cost-effective, ecofriendly, and highly efficient electromagnetic interference shielding materials.

3.
Surg Endosc ; 38(4): 2188-2196, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38448623

ABSTRACT

BACKGROUND: Endoscopy could help detect early gastric cancer (EGC) and improve the prognosis of patients. The aim of this study was to analyze the impact of endoscopy and endoscopic surveillance on the early detection of gastric cancer (GC), GC staging, and treatment selection. METHODS: Patients with GC diagnosed at our center from 2010 to 2022 were retrospectively analyzed and allocated to the short-interval group (had received endoscopy within 3 years before diagnosis), the long-interval group (had received endoscopy more than 3 years before diagnosis), and the unchecked group (had not received endoscopy before diagnosis). The differences in GC staging and treatment modalities among the three groups were analyzed, and the differences in the clinical and pathological features of EGC were further analyzed. RESULTS: One thousand and twenty-five GC patients were included, with 395 cases of EGC and 630 cases of advanced GC. The proportions of EGC in the short-interval, long-interval, and unchecked groups were 98.0%, 84.2%, and 29.8%, respectively (p < 0.001). Among the 387 lesions of 367 EGC patients were resected by endoscopic submucosal dissection (ESD), 341 (88.1%) exhibited curative resection, and 46 (11.9%) involved noncurative resections. Lesions of EGC differed significantly in diameter, depth of invasion, and curative resection rate (p = 0.033, 0.019, and 0.005, respectively). In the short-interval group, 87.8% of the lesions were ≤ 2 cm, 95.6% of the invasion depths were confined to the mucosal layer, and 96.7% of the eCura scores were A or B. Compared with the unchecked group, they had smaller diameters (RR = 0.419, 95% CI 0.234-0.752), shallower invasion depths (RR = 0.286, 95% CI 0.105-0.777), and a higher curative resection rate (RR = 0.215, 95% CI 0.068-0.676). CONCLUSION: Endoscopic surveillance at 3-year intervals can help detect EGC, and the EGC lesions found have smaller diameters and shallower depths of invasion, helping improve the curative resection rate of ESD.


Subject(s)
Endoscopic Mucosal Resection , Stomach Neoplasms , Humans , Retrospective Studies , Stomach Neoplasms/diagnosis , Stomach Neoplasms/surgery , Stomach Neoplasms/pathology , Treatment Outcome , Gastric Mucosa/surgery , Endoscopy, Gastrointestinal , Early Detection of Cancer
4.
Mikrochim Acta ; 191(4): 219, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38530477

ABSTRACT

Hydroxypropyl chitosan-Cs3Bi2Cl9 perovskite quantum dots (HPCS-PQDs) were synthesized by a simple ligand-assisted reprecipitation method via green hydroxypropyl chitosan as the ligand and used as the specific signal of a fluorescence probe to achieve the highly sensitive detection of hexavalent chromium (Cr(VI)) and compared with chitosan-Cs3Bi2Cl9 QDs (CS-PQDs). HPCS-PQDs with multiple active hydroxyl passivations were found to enhance the photoluminescence quantum yield (PLQY) by 90%. After being placed in aqueous solution and irradiated with ultraviolet light for 96 h the fluorescence intensity of HPCS-PQDs remained above 60%. The blue emission of HPCS-PQDs has a good selectivity and short response time (30 s) for Cr(VI). A good linear relationship is established between the fluorescence quenching rate of the HPCS-PQDs and concentration of Cr(VI) from 0.8 to 400 µM, with a limit of detection (LOD) of 0.27 µM. The fluorescence quenching mechanism is the static quenching and internal filtration effect caused by HPCS-PQDs forming a non-fluorescent ground-state complex with Cr(VI). The sensor can not only be used to detect Cr(VI) in water samples with high accuracy but can also be prepared as a test paper for the detection for Cr(VI).

5.
Gastrointest Endosc ; 97(4): 684-693, 2023 04.
Article in English | MEDLINE | ID: mdl-36403805

ABSTRACT

BACKGROUND AND AIMS: We aimed to establish a modified model of the Kyoto classification score and verify its accuracy for predicting Helicobacter pylori (HP) infection during endoscopy. METHODS: Patients who underwent gastroscopy from June 2020 to March 2021 were included in this study. Atrophy, intestinal metaplasia, hypertrophy of the gastric fold, nodularity, diffuse redness, sticky mucus, spotty redness, xanthoma, map-like redness, fundic gland polyp, and regular arrangement of collecting venules (RAC) were recorded according to the Kyoto classification of gastritis. The HP infection status of participants was determined by a 13C breath test, anti-HP antibody, and histopathologic hematoxylin and eosin staining. The modified Kyoto classification scoring model was established based on univariate analysis and logistic regression analysis. The modified scoring model was used to judge the status of HP infection in patients undergoing gastroscopy from July to September 2021 and to evaluate the accuracy of the prediction. RESULTS: Of 667 participants in the derivation dataset, 326 cases had HP infection and 341 cases did not. Atrophy, hypertrophy of the gastric fold, nodularity, diffuse redness, sticky mucus, and spotty redness were associated with HP current infection. Thus, a new scoring model, termed the modified Kyoto classification scoring model, was constructed that included atrophy, hypertrophy of the gastric fold, nodularity, diffuse redness, sticky mucus, spotty redness, fundic gland polyp, and RAC as indicators. To test the model, 808 subjects, including 251 HP-positive patients, comprised the validation dataset. CONCLUSIONS: The modified Kyoto classification scoring model improved the accuracy of endoscopic determination of HP current infection and has clinical application potential in the Chinese population.


Subject(s)
Gastritis , Helicobacter Infections , Helicobacter pylori , Humans , Gastritis/diagnosis , Gastritis/pathology , Gastroscopy , Gastric Mucosa/pathology , Helicobacter Infections/diagnosis , Helicobacter Infections/pathology , Metaplasia/pathology , Atrophy/pathology
6.
Surg Endosc ; 37(7): 5094-5100, 2023 07.
Article in English | MEDLINE | ID: mdl-36920575

ABSTRACT

Magnifying endoscopy is advantageous in detecting precancerous lesions. Our study aimed to clarify its ability to detect easily missed neoplastic lesions on the upper gastrointestinal tract. A retrospective analysis of clinical, endoscopic, and pathological data of cases undergoing gastroscopy was performed using magnifying and routine endoscopy. The detection rates of overall lesions, the ability to identify flat-type neoplastic lesions, and the easily missed neoplastic lesions were compared between the two groups. Endoscopic data from 32,367 patients was analyzed in this study. The use of magnifying endoscopy was an independent factor in identifying flat lesions (OR 2.236, 95% CI 1.969-2.540, p < 0.001), particularly type IIb lesions (OR 3.117, 95% CI 2.333-4.165, p < 0.001). For neoplastic lesions, magnifying endoscopy was also identified as having better sensitivity than routine endoscopy (sensitivity, 90.4% vs. 78.9%, p < 0.001). Similarly, magnifying endoscopy was an independent factor for identifying flat lesions (OR 2.927, 95% CI 2.365-3.621, p < 0.001), especially type IIc lesions (OR 4.415, 95% CI 3.076-6.339, p < 0.001). Magnifying endoscopy was also identified as having superior sensitivity (44.7% vs. 13.3%, p = 0.034) for early cancerous lesions. Compared to routine endoscopy, magnification endoscopy is advantageous in detecting and identifying neoplastic lesions in the upper gastrointestinal tract, especially flat neoplastic lesions and early cancers.


Subject(s)
Stomach Neoplasms , Upper Gastrointestinal Tract , Humans , Retrospective Studies , Stomach Neoplasms/diagnostic imaging , Stomach Neoplasms/pathology , Endoscopy, Gastrointestinal , Gastroscopy , Upper Gastrointestinal Tract/diagnostic imaging
7.
Sensors (Basel) ; 23(10)2023 May 16.
Article in English | MEDLINE | ID: mdl-37430724

ABSTRACT

The existing expectation maximization (EM) and space-alternating generalized EM (SAGE) algorithms are only applied to direction of arrival (DOA) estimation in known noise. In this paper, the two algorithms are designed for DOA estimation in unknown uniform noise. Both the deterministic and random signal models are considered. In addition, a new modified EM (MEM) algorithm applicable to the noise assumption is also proposed. Next, these EM-type algorithms are improved to ensure the stability when the powers of sources are not equal. After being improved, simulation results illustrate that the EM algorithm has similar convergence with the MEM algorithm, the SAGE algorithm outperforms the EM and MEM algorithms for the deterministic signal model, and the SAGE algorithm cannot always outperform the EM and MEM algorithms for the random signal model. Furthermore, simulation results show that processing the same snapshots from the random signal model, the SAGE algorithm for the deterministic signal model can require the fewest computations.

8.
Sensors (Basel) ; 23(23)2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38067681

ABSTRACT

Mobile traffic prediction enables the efficient utilization of network resources and enhances user experience. In this paper, we propose a state transition graph-based spatial-temporal attention network (STG-STAN) for cell-level mobile traffic prediction, which is designed to exploit the underlying spatial-temporal dynamic information hidden in the historical mobile traffic data. Specifically, we first identify the semantic context information over different segments of the historical data by constructing the state transition graphs, which may reveal different patterns of random fluctuation. Then, based on the state transition graphs, a spatial attention extraction module using graph convolutional networks (GCNs) is designed to aggregate the spatial information of different nodes in the state transition graph. Moreover, a temporal extraction module is employed to capture the dynamic evolution and temporal correlation of the state transition graphs over time. Such a spatial-temporal attention network can be further integrated with a parallel long short-term memory (LSTM) module to improve the accuracy of mobile traffic prediction. Extensive experiments demonstrate that the STG-STAN can better exploit the spatial-temporal information hidden in the state transition graphs, achieving superior performance compared with several baselines.

9.
Gut ; 71(2): 238-253, 2022 02.
Article in English | MEDLINE | ID: mdl-34836916

ABSTRACT

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.


Subject(s)
Family Health , Helicobacter Infections/prevention & control , Helicobacter pylori , Infection Control/organization & administration , Adolescent , Adult , Aged , Child , Child, Preschool , China , Consensus , Delphi Technique , Helicobacter Infections/diagnosis , Helicobacter Infections/transmission , Humans , Infant , Middle Aged , Young Adult
10.
Inorg Chem ; 61(14): 5672-5682, 2022 Apr 11.
Article in English | MEDLINE | ID: mdl-35333522

ABSTRACT

Lead halide perovskite quantum dots (QDs) are controversial due to their high lead content. Tin, a low-toxic element with an outer electronic structure similar to that of Pb, becomes a strong candidate for preparing lead-free perovskite QDs. However, tin-based perovskite QDs, especially CsSnCl3 QDs, exhibit poor environmental stability. Herein, we proposed an strategy for highly stable CsSnCl3 QDs using an ionic liquid as a solvent and antioxidant and gelatin as a multidentate ligand and coating material through an in situ method ([AMIM]Cl/gelatin-QDs). The results showed that the abundant active groups of gelatin served as the nucleation growth center for QDs and further passivated QDs. At the same time, the long molecular chain of gelatin can coat the QDs to isolate the environment and fully protect QDs, and the size of QDs grown in gelatin was 5-10 nm. In addition, the oxidation resistance of ionic liquids and the halogen-rich environment formed also played an important role. Even if [AMIM]Cl/gelatin-QDs were treated with water and ultraviolet light simultaneously, its remaining fluorescence intensity was still above 60% within 72 h. Meaningfully, QDs endowed the composite system mildew resistance, which can resist the erosion of gelatin by molds, thereby realizing the system's long-term protection toward CsSnCl3 QDs.

11.
Inorg Chem ; 61(17): 6547-6554, 2022 May 02.
Article in English | MEDLINE | ID: mdl-35447028

ABSTRACT

The toxicity of the Pb element limits the large-scale application of inorganic cesium-lead halide (CsPbX3, with X = Cl, Br, and I) perovskite nanocrystals (NCs). Pb-free cesium-tin halide (CsSnX3) NCs have emerged as a viable alternative because of its excellent photoelectric conversion efficiency. However, the applications are hampered by its poor stability and low photoluminescence quantum yield (PLQY). In this study, extraordinarily stable CsSnCl3 NCs were prepared by exploiting bone gelatin as surface capping agents, which retain 95% of the photoluminescence intensity in water for 55 h. Additionally, after bone gelatin encapsulation, the PLQY of CsSnCl3 NCs was found to increase from 2.17% to 3.13% for the uncapped counterparts because of an improved radiative recombination rate. With such remarkable optical properties of the bone gelatin-CsSnCl3 NCs, metal ions like Fe3+ in aqueous solutions can be readily detected and monitored, signifying the potential application of such stable bone gelatin-CsSnCl3 NCs in the development of fluorescence sensors and detectors.


Subject(s)
Gelatin , Nanoparticles , Calcium Compounds , Cesium , Oxides , Titanium , Water
12.
J Environ Manage ; 238: 235-242, 2019 May 15.
Article in English | MEDLINE | ID: mdl-30852399

ABSTRACT

Zanthoxylum bungeanum Maxim Seed Oil (ZBMSO) is widely distributed in most parts of China, which cannot be edible and extensively consumed due to its high free fatty acids. This paper reports a rational route to utilization of ZBMSO in preparation of nanocomposites which can enhance leather flame retardancy and thermal stability. ZBMSO was synthesized through three-stage process, decoloration, acid reduction and sulfitation to prepare the modified ZBMSO fatliquoring agent (MZBMSO). Then nanocomposites based on MZBMSO and stearate-layered double hydroxide (s-LDH) were prepared via in-situ method. XRD and TEM results indicated that the MZBMSO intercalate into the galleries of s-LDH with uniform dispersion. Compared with MZBMSO, the leather treated by MZBMSO/s-LDH had a remarkable improvement on flame retardancy and superior softness which limiting oxygen index (LOI) increased from 23.6% to 28.0% and smoke density index decreased from 25 to 6.


Subject(s)
Flame Retardants , Nanocomposites , Zanthoxylum , China , Hydroxides , Stearates
13.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(5): 504-510, 2019 07 25.
Article in Zh | MEDLINE | ID: mdl-31901024

ABSTRACT

OBJECTIVE: To assess the application of probe-based confocal laser endomicroscopy (pCLE) in diagnosis of gastric carcinoma and precancerous lesions. METHODS: Patients underwent pCLE in the First Affiliated Hospital of Zhejiang University School of Medicine during December 2013 and November 2014 and in the First Affiliated Hospital of Zhejiang Chinese Medical University during January 2014 and December 2017 were enrolled. The consistency between pCLE diagnosis and pathological diagnosis of gastric lesions, including atrophic gastritis, gastric intestinal metaplasia, low-grade intraepithelial neoplasia and high-grade intraepithelial neoplasia (including gastric carcinoma) was analyzed. RESULTS: Totally 154 gastric lesions from 119 patients were detected by pCLE. Using pathological diagnosis as gold standard, the sensitivity, specificity, coincidence rate and κ value of pCLE diagnosis for atrophic gastritis were 94.34%, 91.09%, 92.21%and 0.83; those indicators for gastric intestinal metaplasia were 84.47%, 92.16%, 87.01% and 0.72. The coincidence rate and κ value of pCLE diagnosis of complete gastric intestinal metaplasia were 0.75 and 0.49; for incomplete gastric intestinal metaplasia were 0.79 and 0.48, respectively. The sensitivity, specificity, coincidence rate and κ value of pCLE diagnosis for low-grade intraepithelial neoplasia were 85.29%, 87.50%, 87.01%and 0.66; those for high-grade intraepithelial neoplasia (including gastric carcinoma) were 95.83%, 97.17%, 96.75%and 0.92. CONCLUSIONS: pCLE can be used for diagnosis of gastric carcinoma and pericancerous lesions and also for typing of gastric intestinal metaplasia.


Subject(s)
Carcinoma , Endoscopy, Gastrointestinal , Microscopy, Confocal , Precancerous Conditions , Stomach Neoplasms , Carcinoma/diagnostic imaging , Humans , Metaplasia , Precancerous Conditions/diagnostic imaging , Sensitivity and Specificity , Stomach/diagnostic imaging , Stomach/pathology , Stomach Neoplasms/diagnostic imaging
14.
Am J Physiol Gastrointest Liver Physiol ; 313(3): G192-G202, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28546285

ABSTRACT

The purpose of this study was to determine the effects and mechanisms of vagal nerve stimulation (VNS) and additive effects of electroacupuncture (EA) on colonic inflammation in a rodent model of IBD. Chronic inflammation in rats was induced by intrarectal TNBS (2,4,6-trinitrobenzenesulfonic acid). The rats were then treated with sham ES (electrical stimulation), VNS, or VNS + EA for 3 wk. Inflammatory responses were assessed by disease activity index (DAI), macroscopic scores and histological scores of colonic tissues, plasma levels of TNFα, IL-1ß, and IL-6, and myeloperoxidase (MPO) activity of colonic tissues. The autonomic function was assessed by the spectral analysis of heart rate variability (HRV) derived from the electrocardiogram. It was found that 1) the area under curve (AUC) of DAI was substantially decreased with VNS + EA and VNS, with VNS + EA being more effective than VNS (P < 0.001); 2) the macroscopic score was 6.43 ± 0.61 in the sham ES group and reduced to 1.86 ± 0.26 with VNS (P < 0.001) and 1.29 ± 0.18 with VNS + EA (P < 0.001); 3) the histological score was 4.05 ± 0.58 in the sham ES group and reduced to 1.93 ± 0.37 with VNS (P < 0.001) and 1.36 ± 0.20 with VNS + EA (P < 0.001); 4) the plasma levels of TNFα, IL-1ß, IL-6, and MPO were all significantly decreased with VNS and VNS + EA compared with the sham ES group; and 5) autonomically, both VNS + EA and VNS substantially increased vagal activity and decreased sympathetic activity compared with sham EA (P < 0.001, P < 0.001, respectively). In conclusion, chronic VNS improves inflammation in TNBS-treated rats by inhibiting proinflammatory cytokines via the autonomic mechanism. Addition of noninvasive EA to VNS may enhance the anti-inflammatory effect of VNS.NEW & NOTEWORTHY This is the first study to address and compare the effects of vagal nerve stimulation (VNS), electrical acupuncture (EA) and VNS + EA on TNBS (2,4,6-trinitrobenzenesulfonic acid)-induced colitis in rats. The proposed chronic VNS + EA, VNS, and EA were shown to decrease DAI and ameliorate macroscopic and microscopic damages in rats with TNBS-induced colitis via the autonomic pathway. The addition of EA to VNS provided a significant effect on the behavioral assessment of inflammation (DAI, CMDI, and histological score) but not on cytokines or mechanistic measurements, suggesting an overall systemic effect of EA.View this article's corresponding video summary at https://youtu.be/-rEz6HMkErM.


Subject(s)
Colitis/chemically induced , Colitis/therapy , Electroacupuncture , Inflammation/therapy , Vagus Nerve Stimulation , Animals , Cytokines/genetics , Cytokines/metabolism , Gene Expression Regulation , Male , Peroxidase , Rats , Rats, Sprague-Dawley , Time Factors , Trinitrobenzenesulfonic Acid/toxicity
15.
Sensors (Basel) ; 17(6)2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28587171

ABSTRACT

This paper proposes a wireless powered communication network (WPCN) assisted by backscatter communication (BackCom). This model consists of a power station, an information receiver and multiple users that can work in either BackCom mode or harvest-then-transmit (HTT) mode. The time block is mainly divided into two parts corresponding to the data backscattering and transmission periods, respectively. The users first backscatter data to the information receiver in time division multiple access (TDMA) during the data backscattering period. When one user works in the BackCom mode, the other users harvest energy from the power station. During the data transmission period, two schemes, i.e., non-orthogonal multiple access (NOMA) and TDMA, are considered. To maximize the system throughput, the optimal time allocation policies are obtained. Simulation results demonstrate the superiority of the proposed model.

16.
Sensors (Basel) ; 16(12)2016 Nov 29.
Article in English | MEDLINE | ID: mdl-27916825

ABSTRACT

This paper considers a backscatter communication (BackCom) system including a reader and N tags, where each tag receives excitation signals transmitted by the reader and concurrently backscatters information to the reader in time-division-multiple-access (TDMA) mode. In this system, we aim to maximize the total system goodput by jointly optimizing reader transmission power, time allocation, and reflection ratio for the cases of passive and semi-passive tags. For each case, an optimization problem is formulated, which is non-convex and can be solved by being decomposed into at most N feasible sub-problems based on the priority of allocated reader transmission power. First, for the passive tags case, by solving the convex sub-problems sequentially and comparing their maximum total goodput, we derive the optimal resource allocation policy. Then, for the semi-passive tags case, we find a close-to-optimal solution, since each sub-problem can be reformulated as a biconvex problem, which is solved by a proposed block coordinate descent (BCD)-based optimization algorithm. Finally, simulation results demonstrate the superiority of the proposed resource allocation policies.

17.
Zhonghua Nei Ke Za Zhi ; 54(5): 445-51, 2015 May.
Article in Zh | MEDLINE | ID: mdl-26080826

ABSTRACT

OBJECTIVE: To evaluate the efficacy of probiotics to treat irritable bowel syndrome (IBS). METHODS: Publications from database including PubMed, the Cochrane Library, Embase, CNKI, CBM and WanFang Data were searched up to August 31, 2014. The randomized controlled trials (RCTs) on probiotics to treat IBS were eligible. The related articles were extracted and cross-checked independently by two reviewers. Methodological quality of trials was evaluated according to Cochrane Handbook 5.1.0 criteria. Meta-analysis was conducted using RevMan 5.2 software. RESULTS: A total of 17 RCTs involving 1 700 patients were included. Results of meta-analyses showed that compared with the placebo, probiotics was statistically better in improving the overall symptoms integral (SMD = -0.20, 95% CI -0.33--0.07, P = 0.002), alleviating abdominal pain/discomfort (SMD = -0.19, 95% CI -0.29--0.09, P<0.001), relieving abdominal distention (SMD = -0.16, 95% CI -0.28--0.03, P = 0.020), and defecation discomfort (SMD = -0.22, 95% CI -0.42--0.02, P = 0.030). There was no statistical significance in the overall quality of life (SMD = -0.08, 95% CI -0.07-0.23, P = 0.290) and adverse effect ratio (RR = 1.08, 95% CI 0.79-1.49, P = 0.630). CONCLUSION: Probiotics have beneficial effects on IBS, which can improve the patients' symptoms and with less adverse reaction. Due to the bias, further large-scale, multicenter and high-quality RCTs are required to unify outcome indicators, further define sensitive strain, and standardize its usage, dosage and course of treatment.


Subject(s)
Irritable Bowel Syndrome/therapy , Probiotics/therapeutic use , Humans , Irritable Bowel Syndrome/psychology , Probiotics/adverse effects , Quality of Life , Randomized Controlled Trials as Topic , Reference Standards , Treatment Outcome
18.
Zhonghua Xin Xue Guan Bing Za Zhi ; 43(3): 234-8, 2015 Mar.
Article in Zh | MEDLINE | ID: mdl-26269342

ABSTRACT

OBJECTIVE: To investigate the feasibility of using lower iodine concentration (270 mgI/ml) contrast medium, lower X-ray tube voltage (100 kVp) and iterative reconstruction (IR) to reduce both iodine load and radiation dose but keep the image quality of coronary CT angiography (CCTA). METHODS: A total of 80 consecutive patients with suspected coronary artery disease were prospectively assigned to one of two groups via computer central system from January to May 2013. The control group (n = 40) was scanned using dual-source CCTA protocols of 120 kV, 370 mgI/ml Iopromide and filtered back projection reconstruction with a vascular algorithm (B26f). The study group (n = 40) was scanned using 100 kV, 270 mgI/ml Iodixanol and sinogram affirmed iterative reconstruction with a vascular algorithm (I26f). Other scan parameters and contrast injection protocol were similar between the two groups. Attenuation in the ascending aorta and coronary arteries along with image noise were measured. Images were reconstructed, measured and graded, and iodine load and effective radiation dose were calculated. RESULTS: The body mass index ((25.3 ± 3.0) kg/m² vs. (25.4 ± 3.0)kg/m², P = 0.852), image quality scores (4.70 ± 0.52 vs. 4.63 ± 0.59, P = 0.545), mean signal-to-noise ratios (22.2 ± 5.5 vs. 23.6 ± 5.8, P = 0.277), and contrast-to-noise ratios (35.6 ± 17.6 vs. 41.1 ± 17.6, P = 0.163) were similar between the control group and study group. Mean iodine loads were significantly reduced in the study group ((18.49 ± 0.75)g) compared to control group ((25.27 ± 0.94)g), P< 0.001). Mean effective radiation doses were also significantly reduced in the study group ((2.31 ± 0.73) mSv) compared to that in control group ((3.52 ± 1.16) mSv), P< 0.001). CONCLUSION: Use of low X-ray tube voltage and iterative reconstruction allows lower iodine load and effective radiation dose application at CCTA without image quality reduction.


Subject(s)
Coronary Angiography , Algorithms , Aorta , Body Mass Index , Contrast Media , Coronary Artery Disease , Feasibility Studies , Fluoroscopy , Humans , Injections, Intravenous , Iodine , Iohexol/analogs & derivatives , Tomography, X-Ray Computed , Triiodobenzoic Acids
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