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1.
Sci Total Environ ; 912: 168991, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38043808

ABSTRACT

Exploring the influencing factors of potential evapotranspiration (PET) is of great significance for further understanding the causes of climate change and improving agricultural irrigation efficiency. In this study, modified Mann-Kendall analysis was used to elucidate the temporal variation characteristics of meteorological factors and PET based on a dataset from 710 meteorological stations in China. Furthermore, we revealed the main factors that influence the temporal and climate heterogeneity of PET by combining sensitivity analysis with the contribution analysis method. The results showed that 1) climate factors and PET exhibited trend changes on a yearly scale, with slope variation ranges of temperature (T), relative humidity (RH), net radiation (RN), wind speed (U) and PET of 0.03-0.04 °C/a, 0.03-0.08 %/a, 0.001-0.007[MJ/(m2/day)]/a, -0.005 to -0.012(m/s)/a and -0.30-0.38 mm/a, respectively. 2) The sensitivity coefficient fluctuated greatly inter-annually, but the trend was more pronounced inter-annually. Most sensitive factor for PET was RN in hyperarid (HAR), arid (AR) and semiarid regions (SAR), while it changed to RH in semihumid (SHR) and humid regions (HR). PET was more sensitive to RN in dry and relatively wet hot seasons, while it changed to RH during wet and relatively dry cold seasons. 3) PET changes were determined by the relative changes and the sensitivity coefficient, and significant temporal heterogeneity was observed. In HAR, AR, SAR and SHR, the relative changes in T and U result in higher contributions. In HR, PET changes were primarily caused by its higher sensitivity to RH and RN. 4) In dry region and humid-cold seasons, the bigger relative changes of climate factors were the main drivers affecting PET changes, but in humid region and arid-hot seasons, the they were determined by the strong nonlinear relationship between PET and factors. This finding holds great significance for the scientific understanding of the evolution mechanism of PET under changing environments.

2.
Appl Opt ; 61(28): 8435-8445, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-36256158

ABSTRACT

Hemispherical resonant gyroscopes (HRGs) are solid-state vibration gyroscopes with the highest precision and are widely used in the aerospace field. The core part of the gyroscope is the resonator, which is a thin-walled hemispherical shell. Surface error and thickness variation of a hemispherical shell causes frequency splitting, which degrades the performance of the HRG. In order to guide the mass leveling of hemispherical resonator, this paper presents a new method for scanning measurement of the surface error and thickness variation of hemispherical resonators. First, a multi-axis platform is designed for noncontact sensor scanning measurements along the meridian and latitudinal lines of the hemispherical resonator. Second, the error model of the measurement system is established. The surface error of the standard sphere is measured to calibrate and compensate for the assembly errors of the measuring device. In addition, the identification accuracy of assembly errors and the influence of assembly errors on thickness measurement are simulated by a computer. Finally, the surface error and thickness variation of the hemispherical resonators are measured. The method is experimentally demonstrated and validated with a wavefront interferometry test. The results show that the method can achieve high precision and high repeatability, which is instructive for assessment of the machining error and further evaluation of the hemispherical resonator.

3.
Biotechnol Appl Biochem ; 68(4): 896-901, 2021 Aug.
Article in English | MEDLINE | ID: mdl-32822079

ABSTRACT

Researches have proved that increasing level of prostate-specific antigen (PSA) is an indicator for the progression of prostate cancer. The present study was focused to determine the PSA level by using anti-PSA antibody conjugated iron oxide nanoparticles, as the probe immobilized on the gap-fingered electrode sensing surface. The detection limit and sensitivity were found at the level of 1.9 pg/mL on the linear regression curve (y = 1.6939x - 0.5671; R² = 0.9878). A dose-dependent liner range was found from 1.9 until 60 pg/mL. Further, PSA was spiked in human serum and did not affect the interaction of PSA and its antibody. This method of detection quantifies the level of PSA, which helps to diagnose prostate cancer at its earlier stage.


Subject(s)
Biomarkers, Tumor/blood , Magnetic Iron Oxide Nanoparticles/chemistry , Prostate-Specific Antigen/blood , Prostatic Neoplasms , Electrodes , Humans , Male , Prostatic Neoplasms/blood , Prostatic Neoplasms/diagnosis
4.
Pak J Med Sci ; 36(7): 1664-1670, 2020.
Article in English | MEDLINE | ID: mdl-33235594

ABSTRACT

OBJECTIVE: To observe the clinical significance of modified sling in the treatment of moderate stress urinary incontinence (SUI). METHODS: From January 2016 to January 2019, eighty patients with moderate urinary incontinence who were hospitalized in our hospital were randomly divided into two groups. 40 patients in the experimental group underwent modified sling transvaginal tension-free mid-urethral suspension. Modification method of the sling: cut the sling to a remaining length of about 6~7cm, properly connect the barbed sutures (V-LOCK) on both sides of the sling, and insert the urinary incontinence sling from the urethra to the obturator membrane, from the obturator membrane to the thigh. The inner skin area is replaced by the V-LOCK line. The 40 patients in the control group were unmodified ordinary slings. The operation time, the local pain of the inner thigh after the operation, and the improvement of postoperative urinary incontinence symptoms were compared and analyzed between the two groups. RESULTS: Both groups of patients were successfully operated. The operation time was 16.36 minutes in the experimental group and 27.18 minutes in the control group. The difference in operation time between the two groups was statistically significant (p=0.00); the catheter was pulled out on the third day after the operation. One patient in the group had urinary effort, four patients still had urinary incontinence symptoms, the remaining 35 patients had good urinary control (effective rate 87.5%), five patients in the control group still had urinary incontinence, two patients had urinary effort, and the remaining 33 patients had urinary control Good, (effective rate 87.5%), there was no significant difference in surgical effectiveness between the two groups (p=0.53); follow-up for 12 to 36 months, no significant long-term complications occurred, the pain score of the inner thigh of the experimental group was significantly lower than that of the control group ,statistically significant (p=0.04). CONCLUSION: The efficacy of the modified sling in the treatment of moderate SUI is the same as that of the traditional sling, but the operation time is shorter, the operation is simpler, and the local pain is significantly reduced.

5.
Cell Prolif ; 52(4): e12616, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31050052

ABSTRACT

OBJECTIVES: To investigate the impact of silver nanoparticles (AgNPs) on the biofilm growth and architecture. MATERIALS AND METHODS: Silver nitrate was reduced by d-maltose to prepare AgNPs in the presence of ammonia and sodium hydroxide. The physicochemical properties of AgNPs were characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and inductively coupled plasma mass spectrometry. The development of biofilm with and without AgNPs was explored by crystal violet stain. The structures of mature biofilm were visually studied by confocal laser scanning microscopy and scanning electron microscopy. Bacterial cell, polysaccharide and protein within biofilm were assessed quantitatively by colony-counting method, phenol-sulphuric acid method and Bradford assay, respectively. RESULTS: The spherical AgNPs (about 30 nm) were successfully synthesized. The effect of AgNPs on Pseudomonas aeruginosa biofilm development was concentration-dependent. Biofilm was more resistant to AgNPs than planktonic cells. Low doses of AgNPs exposure remarkably delayed the growth cycle of biofilm, whereas high concentration (18 µg/mL) of AgNPs fully prevented biofilm development. The analysis of biofilm architecture at the mature stage demonstrated that AgNPs exposure at all concentration led to significant decrease of cell viability within treated biofilms. However, sublethal doses of AgNPs increased the production of both polysaccharide and protein compared to control, which significantly changed the biofilm structure. CONCLUSIONS: AgNPs exert concentration-dependent influences on biofilm development and structure, which provides new insight into the role of concentration played in the interaction between antibacterial nanoparticles and biofilm, especially, an ignored sublethal concentration associated with potential unintended consequences.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Metal Nanoparticles/administration & dosage , Pseudomonas aeruginosa/drug effects , Silver/pharmacology , Cell Survival/drug effects , Microscopy, Electron, Transmission/methods , Particle Size , Plant Extracts/pharmacology
6.
Chembiochem ; 20(12): 1508-1513, 2019 06 14.
Article in English | MEDLINE | ID: mdl-30702811

ABSTRACT

One-dimensional nanotubes are of considerable interest in materials and biochemical sciences. A particular desire is to create DNA nanotubes with user-defined structural features and biological relevance, which will facilitate the application of these nanotubes in the controlled release of drugs, templating of other materials into linear arrays and the construction of artificial membrane channels. However, little is known about the structures of assembled DNA nanotubes in solution. Here we report an in situ exploration of segmented DNA nanotubes, composed of multiple units with set length distributions, by using synchrotron small-angle X-ray scattering (SAXS). Through joint experimental and theoretical studies, we show that the SAXS data are highly informative in the context of heterogeneous mixtures of DNA nanotubes. The structural parameters obtained by SAXS are in good agreement with those determined by atomic force microscopy (AFM), transmission electron microscopy (TEM), and dynamic light scattering (DLS). In particular, the SAXS data revealed important structural information on these DNA nanotubes, such as the in-solution diameters (≈25 nm), which could be obtained only with difficulty by use of other methods. Our results establish SAXS as a reliable structural analysis method for long DNA nanotubes and could assist in the rational design of these structures.


Subject(s)
DNA/chemistry , Nanotubes/chemistry , Nucleic Acid Conformation , Scattering, Small Angle , X-Ray Diffraction/methods
7.
ACS Appl Bio Mater ; 2(1): 226-235, 2019 Jan 22.
Article in English | MEDLINE | ID: mdl-35016345

ABSTRACT

Graphene-based nanomaterials (GMs) are served as great promising agents for the prevention and therapy of infectious diseases. However, their dental applications remain to be evaluated, especially under the context of the oral microbial community. Here, we examined the exposure-response of salivary bacterial community to two types of GMs, that is, graphene oxide (GO) and GO-silver nanoparticles (AgNPs). Both GO and GO-AgNPs showed lethal effect against salivary bacteria in a concentration-dependent manner, and the antibacterial capacity of GO-AgNPs is superior to GO. Interestingly, the salivary bacterial community enhanced the tolerance to GMs as compared to homogeneous bacteria. High-throughput sequencing revealed that both 80 µg/mL GO and 20 µg/mL GO-AgNPs significantly altered the biodiversity of salivary bacterial community. Especially, they increased the relative abundance of Gram-positive bacteria compared to the untreated sample, notably Streptococcus, suggesting that the bacterial wall structure plays a critical role in resisting the damage of GMs. Although GMs could effectively limit the salivary bacterial activity and cause changes in bacterial community structure, they are not toxic to mammalian cell lines. We envision this study could provide novel insights into the application of GMs as "green antibiotics" in nanomedicine.

8.
Nanoscale ; 10(41): 19603-19611, 2018 Nov 07.
Article in English | MEDLINE | ID: mdl-30325394

ABSTRACT

Biofilms with positive and negative actions ubiquitously affect medical infections, environmental remediation and industrial processes. However, it remains challenging to control the growth of harmful biofilms as well as to exploit the use of beneficial biofilms. Here we investigated the effect of an antibacterial graphene oxide-silver nanoparticles (GO-AgNPs) composite on Pseudomonas aeruginosa biofilm formation. We found that GO-AgNPs prevented biofilm formation in a dose-dependent manner, with a threshold of 15 µg mL-1. Interestingly, the bacterial biomass significantly decreased, but extracellular polymeric substance (EPS) production remarkably increased in mature biofilms treated with GO-AgNPs of an appropriate concentration, suggesting that GO-AgNPs effectively modulate biofilm development and structure. Moreover, we established that GO-AgNPs caused bacterial death via both physical damage and oxidative stress, showing the synergic action of GO and AgNPs. These findings facilitate the use of graphene-based nanocomposites for greener antibiotic applications.

9.
Pak J Med Sci ; 34(3): 535-539, 2018.
Article in English | MEDLINE | ID: mdl-30034411

ABSTRACT

OBJECTIVE: To compare the therapeutic effects of visual standard channel combined with visual superfine precision puncture channel or super-mini percutaneous nephrolithotomy (PCNL) on multiple renal calculi. METHODS: A total of 86 patients with multiple renal calculi were retrospectively analyzed. According to different working channels, they were divided into a visual puncture channel group (visual puncture standard channel combined with visual superfine precision puncture channel, n=38) and a conventional puncture channel group (standard channel combined with super-mini channel, n=48). The two groups were compared in terms of time of channel establishment, surgical time, reduction of hemoglobin, phase I clearance rate of calculi, and surgical complications. RESULTS: The time of establishing visual/conventional standard channel was (4.5±1.5) min vs. (6.8±1.8) minutes (t=6.326, P=0.000), and the time of establishing visible superfine/super-mini channel was (4.52±0.97) minutes vs. (7.76±1.35) minutes (t=2.017, P=0.000). The surgical time was (92±15) minutes vs. (115±13) minutes (t=26.640, P=0.000). The Phase-I clearance rate was 86.7% (33/38) vs. 87.5% (42/48) (χ2=0.008, P=0.928), the reduction of hemoglobin was (12.21±2.5) g/L vs. (13.22±3.5) g/L (t=2.017, P=0.137), the blood transfusion rate was 13.16 (5/38) vs. 8.33% (4/48) (χ2=0.006, P=0.941), the postoperative fever rate was 7.89% (3/38) vs. 14.58 (7/48) (χ2=0.006, P=0.941), and the hospitalization stay length was (6.5±1.0) vs. (6.6±1.2) (t=0.413, P=0.681). There were no significant differences between the two groups. CONCLUSION: Both surgical approaches had high clearance rates of multiple renal calculi, safety, reliability and few complications. However, compared with the conventional puncture channel, the visual one was easy to operate and dramatically shortened the time of establishment, thus being safer and more accurate.

10.
China Journal of Endoscopy ; (12): 97-100, 2017.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-668213

ABSTRACT

Objective To observe the clinical application of all seeing needle system system in diagnosis and treatment of patients with hematospermia. Methods From May 2015 to September 2016, 22 patients with hemospermia were treated with seminal vesiculoscopy and seminal vesicle lithotripsy by using a all seeing needle system instead of traditional seminal vesicle. Results All the patients were successfully found the seminal vesicle gland and successfully entered the seminal vesicle gland, 16 cases had chronic inflammation of the seminal vesicle, dilute iodine rinse, 6 cases of seminal vesicle, holmium laser lithotripsy, stone basket to remove. The average operation time was (15.7 ± 6.2) min. The catheterization was performed the next day after operation. The average hospital stay was 2 d. After follow-up for 3 to 6 months, 20 patients had disappeared (90.9%). No complication was found Disease and long-term complications. Conclusion The all seeing needle system can replace the traditional seminal vesicle for the operation of seminal vesicle. The puncture system is short, directional and maneuverable. It has advantages of short operation time, simple operation, easy to master and no complications.

11.
Korean J Urol ; 56(7): 519-24, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26175871

ABSTRACT

PURPOSE: To assess the safety and efficacy of an ultramini nephrostomy tract, which we were using for the first time, combined with flexible ureterorenoscopy (URS) in the treatment of pediatric patients with multiple renal calculi. MATERIALS AND METHODS: Twenty pediatric patients (age, ≤ 6 years) underwent ultramini percutaneous nephrolithotomy (PCNL) combined with flexible URS. The group had multiple renal calculi, which were bilateral in 3 cases and were located in a total of 23 sites. The calculi were located in 2 calyces in 10 cases, scattered in more than 2 calyces in 7 cases, and limited to 1 calyx in 3 cases. The average patient age was 37.35 months (range, 14-68 months). The average stone diameter was 2.0 cm (range, 1-3.0 cm). In all patients, an ultramini nephrostomy tract was established under ultrasound guidance (dilated to F10) with simultaneous sheath placement. The flexible URS was placed into the collecting system during holmium laser lithotripsy. RESULTS: When ultramini PCNL was combined with flexible ureterorenoscopic holmium laser lithotripsy, the complete stone-free rate was 87% (20/23). The average level of hemoglobin decreased to 1.0 g/dL after the operation. No blood transfusions were needed. Levels of blood urea nitrogen, creatinine, and C-reactive protein were not significantly different before and after the operation. The average duration of hospitalization was approximately 4.85 days, and all cases were followed up for 6 to 12 months. No complications were found. CONCLUSIONS: Ultramini PCNL combined with flexible ureterorenoscopic holmium laser lithotripsy is a safe and effective treatment for children with multiple renal calculi.


Subject(s)
Kidney Calculi/surgery , Nephrostomy, Percutaneous/methods , Ureteroscopy/methods , Adolescent , Adult , Aged , Female , Humans , Kidney Calculi/pathology , Kidney Calculi/ultrastructure , Length of Stay/statistics & numerical data , Lithotripsy, Laser/methods , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Ultrasonography, Interventional/methods , Young Adult
12.
Zhonghua Nan Ke Xue ; 17(11): 1011-3, 2011 Nov.
Article in Chinese | MEDLINE | ID: mdl-22141273

ABSTRACT

OBJECTIVE: To investigate the effect of transurethral resection of the prostate (TURP) in the treatment of urinary retention following seed implantation for prostate cancer. METHODS: We treated 2 cases of urinary retention following seed implantation for prostate cancer by TURP, and analyzed their clinical data. RESULTS: The operations were successful in both of the cases, with mean operation time of 60 min. Postoperative nocturnal urination of the patients averaged 2 times per night as compared with 5 - 6 times per night preoperatively, and their scores on IPSS and quality of life were significantly improved after surgery. CONCLUSION: TURP affords satisfactory results in the treatment of urinary retention following seed implantation for prostate cancer patients.


Subject(s)
Prostatic Neoplasms/surgery , Transurethral Resection of Prostate/methods , Urinary Retention/surgery , Aged , Humans , Male , Postoperative Period
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