Remarkably Improvement in Antibacterial Activity of Carbon Nanotubes by Hybridizing with Silver Nanodots.

In view of their super capacity of adsorbing microbial, the carbon nanotubes (CNTs) were used as the carriers for in situ synthesizing well-dispersed and small-sized silver nanodots (AgND), to prepare a new type of antibacterial agent with remarkably improved activity. Polyethyleneimine (PEI) was introduced as a linkage for guaranteeing the as-generated AgND to be anchored onto the CNTs and to prevent them from agglomeration. The obtained hybridizing materials were characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy, and the results showed that the AgND with an average size of 2.6 nm were uniformly loaded on surfaces of CNTs. There existed special interactions between silver atoms and CNTs. The antibacterial activities of the as-prepared hybrids against Escherichia coli were evaluated by disk diffusion assay method and minimal inhibitory concentration measurements. The results showed that the as-prepared hybrids displayed a remarkable improvement in antibacterial activity as compared to CNTs, acidified-CNTs and even the identical silver amount of AgNO3 solution, which was mainly attributed to the small size of AgND and the hybridizing effect between AgND and CNTs.

Quick pre-correction of a grating fringe for phase measuring profilometry.

In this paper, for a phase measuring profilometry (PMP) system based on a digital light projector, a novel method of grating fringe quick pre-correction is proposed. In the actual engineering conditions, it is impractical to strictly limit the geometry of the system. So grating fringes on the reference plane often appear as distortions of keystone and period broadening, which are difficult to completely eliminate in the traditional calibration process. A pre-correction method based on analytic spatial transform is designed to solve these problems individually. The correction process occurs before the digital micromirror device image is generated, and theoretically, it can be compatible with most existing PMP correction and calibration methods. The correction is simple and completely implicit, and does not require a special calibration target. The correction is quick, only needs to project and shoot a fringe pattern and a corner pattern, and can be completed within a few seconds. A simulation and several experiments were carried out to verify the effectiveness of this method.

Optimized design of six-wave fiber optical parametric amplifiers by using a genetic algorithm.

A governing equation of the six-wave fiber optical parametric amplifier (FOPA) for the power and phase difference evolution of the six interacting waves is deduced. To optimize the gain of the six-wave FOPA, a multivariate stochastic optimization algorithm, i.e., the genetic algorithm (GA), is applied. The effect of pump depletion on the gain characteristic of the six-wave FOPA is emphasized and the effect of the fiber length, the wavelength, and the power of two pumps on bandwidth, flatness, and magnitude of the gain spectrum has also been studied. A broader and flatter six-wave FOPA gain is obtained by adopting optimum design parameters, which theoretically provide a uniform gain of 65 dB with 0.3 dB uniformity over a 110 nm bandwidth for the six-wave FOPA.

Treatment of Ulnar Coronoid Process Fracture Using the Anterior Neurovascular Interval Approach: A Retrospective Clinical Study with Short- to Mid-term Follow-up.

OBJECTIVE: Numerous surgical techniques for addressing ulnar coronoid process fractures are available; however, a consensus on the optimal approach remains elusive. This study aimed to use the anterior neurovascular interval approach for the surgical management of ulnar coronoid process fractures and to evaluate its clinical outcomes over short- to mid-term follow-up. METHODS: This retrospective clinical study included 20 patients with ulnar coronoid process fractures who were treated using the anterior neurovascular interval approach between January 2018 and December 2022. Participants comprised 16 males and four females, aged between 20 and 64 years (mean, 34.3 ± 12.44 years). Clinical and radiological evaluations were based on elbow joint range of motion (ROM), Visual analogue scale (VAS), and Mayo elbow performance score (MEPS). A paired t-test was used to compare the pre-operative and final follow-up VAS and MEPS scores. RESULTS: The follow-up duration for all patients was at least 12 months (average, 12.65 ± 1.60 months). At the final follow-up, measurements of elbow ROM included a mean extension of 2.85 ± 3.17°, mean flexion of 135 ± 7.25°, mean pronation of 86.4 ± 4.56°, and mean supination of 84.85 ± 5.54°. All participants reached their target MEPS, with an average score of 97.25 ± 4.72 points, and the final mean VAS score was 0.2 ± 0.52 points. The VAS score was significantly lower and MEPS score was higher at the final follow-up than those before surgery (p < 0.05). Throughout the follow-up period, all the fractures united, and the stability of the affected elbows was satisfactory. CONCLUSION: Employing the anterior neurovascular interval approach for open reduction and internal fixation to manage coronoid process fractures effectively facilitates anatomical restoration and robust fixation of ulnar coronoid process fractures.

Identifying groundwater characteristics and controlling factors in Jiaozhou Bay's northern coastal region, China: a combined approach of multivariate statistics, isotope analysis, and field empirical investigations.

Explicit identification of hydrochemical processes and their controlling factors within groundwater systems is critical for the sustainable utilization of water resources in coastal urban areas. This study was undertaken in the North Coastal Region of Jiaozhou Bay (NCRJB), located in the eastern part of Shandong Province, China, an area grappling with significant issues of groundwater quality degradation and water scarcity. A total of 105 groundwater samples and 34 surface water samples, collected from 2020 to 2024, were analyzed and studied using various hydrogeological tools, multivariate statistical analyses, and water quality assessment methods. These include the Piper diagram, hydrochemical facies evolution diagram (HFE-D), Principal Components Analysis (PCA), correlation analysis, stable isotope analysis, Water Quality Index (WQI), and USSL diagrams. The results indicated that all surface water and pore groundwater samples were categorized as Na-Cl type, exhibiting high Total Dissolved Solids (TDS) and Electrical Conductivity (EC) values, characteristics that render them poor to unsuitable for drinking and irrigation purposes. The fracture groundwater is predominantly of the Ca-Na-Cl mixed type, with average suitability for irrigation and a limited proportion (22.5%) deemed suitable for drinking. Seawater intrusion, primarily through the surface water system, and the impact of human activities were identified as the predominant controlling factors con-tributing to the degradation of the local groundwater environment. Field empirical investigations further validated the results derived from hydrogeological assessments, multivariate statistical analyses, and isotopic approaches. The long-term shifts in hydrochemical properties, along with the latent threat of seawater intrusion, exhibit an upward trend during the dry season and show a certain degree of mitigation during the wet season. This study highlights that field investigations, in conjunction with hydrochemical tools, multivariate statistical analyses, and stable isotope analysis, can successfully furnish reliable insights into the predominant mechanisms governing regional groundwater evolution within the context of long-term and intricate envi-ronmental settings.

A study based on high-density data examines the current status and evolution laws of heavy metal environmental capacity in the Bardawu area of the Qinghai-Tibet Plateau.

As the first ladder of China, the Qinghai-Tibet Plateau has always been known as the "roof of the world". Its environmental carrying capacity can be estimated more accurately than other regions because of its harsh natural environment, low population density, limited industrial and agricultural development, and low human activities. However, the current ecological risks of Co and threshold research are limited, and there is a lack of awareness of W's environmental risks. Hence, this study assessed the ecological support potential of the Bardawu region within Dulan County, Qinghai Province, using 7373 soil specimens, determined regional soil baseline measures, and applied the substance equilibrium linear technique along with the ecological aggregate indicator technique to examine the heavy metal content of the soil. A comprehensive evaluation of the environmental capacity and health risks was conducted to provide a reference for pastoral planning. The findings indicated that the cumulative static ecological capacity of the six trace heavy elements in the soil was ranked as follows: Cr > Li > Ni > Cu > W > Co, with W and Co positioned as the final pair. The remaining areas with a high environmental capacity were predominantly found in the study zone. The central sector exhibited diminished environmental capacity in the southwest and northeast and presented a contamination hazard. Land use, soil type, and geological type considerably affected the six elements in the study area at the p < 0.05. The Bardawu region's mean comprehensive index of soil environmental capacity was 0.98, indicating an intermediate level of environmental capacity and a moderate health risk. This study focuses on the geological context and influence of pastoral activities on the soil, augments the distribution of various elements across the Tibetan Plateau, and suggests preliminary soil governance strategies. The findings of this study lay the groundwork for soil environmental conservation and remediation efforts in highland regions.

Gain optimization of fiber optical parametric amplifier based on genetic algorithm with pump depletion.

A method to optimize the gain of a fiber optical parametric amplifier (FOPA) is presented by using a genetic algorithm (GA), which can determine the parameters of FOPA and avoid the trouble of trial and error to achieve it. The effect of pump depletion on the gain characteristic of the FOPA is emphasized, and the effects of the fiber length, the wavelength, and the power of two pumps on bandwidth, flatness, and magnitude of the gain spectrum are also studied. According to the presentation, fiber length and the wavelength of the two pumps are selected to be the variable parameters in the GA. When the parameters of the fiber are determined, with the numerical simulation, the optimum combination scheme between those chosen variables could be obtained by the algorithms with the result of the gain optimization of FOPA.

Clinical Analysis of the Frosch Approach in the Treatment of Posterolateral Tibial Plateau Fractures Combined with Lateral Tibial Plateau Fractures.

OBJECTIVE: The treatment of posterolateral tibial plateau fractures is difficult, and providing sufficient exposure and effective fixation is a challenge. There is great controversy regarding the surgical approach for posterolateral tibial plateau fractures. The purpose of the study was to investigate the clinical effects of open reduction and internal fixation using the Frosch approach for the treatment of posterolateral tibial plateau fractures combined with lateral tibial plateau fractures. METHODS: Data from 19 patients with posterolateral tibial plateau fractures combined with lateral tibial plateau fractures treated from May 2018 to January 2022 were retrospectively analyzed. There were nine men and 10 women, ranging in age from 22 to 62 years, with an average age of 45.6 years. All patients were treated using the Frosch approach. Under direct vision, the posterolateral and lateral fractures were reduced, and full bone grafting was performed. We reshaped the oblique "T" shaped plate for the distal radius and placed it on the posterolateral tibial plateau to fix the posterolateral fractures. The lateral inverted "L" shaped locking plate was placed on the lateral tibial plateau to fix the lateral tibial plateau fractures. Within 2 weeks after the operation, the patients were instructed to perform knee joint function exercises within 90°. At the last follow-up, the Rasmussen radiological criteria were used to evaluate the effectiveness of fracture reduction and fixation. And the knee joint function was evaluated using Rasmussen functional score. RESULTS: The operation time ranged from 100 to 180 min, with an average of 134.2 min; intraoperative blood loss ranged from 20 to 150 mL, with an average of 66.8 mL. The follow-up duration ranged from 14 to 58 months, with an average of 36.2 months. There were no complications, such as vascular or nerve injury or incision infection. Fracture healing was achieved in all patients, and the healing time ranged from 10 to 14 weeks, with an average of 11.2 weeks. During the follow-up period, there was no loosening or breakage of the internal fixation, varus or valgus deformity of the knee joint, re-collapse of the articular surface, or instability of the knee joint. At the last follow-up, the effectiveness of fracture reduction and fixation was excellent in 13 patients and good in six patients. And the knee joint function was excellent in 17 patients and good in two patients. CONCLUSION: The Frosch approach for open reduction and internal fixation in the treatment of posterolateral tibial plateau fractures combined with lateral tibial plateau fractures has a definite clinical benefit and is worthy of promotion and application.