While working on fire ground, firefighters risk their well-being in a state where any incident might cause not only injuries, but also fatality. They may be incapacitated by unpredicted falls due to ...floor cracks, holes, structure failure, gas explosion, exposure to toxic gases, or being stuck in narrow path, etc. Having acknowledged this need, in this study, we focus on developing an efficient portable system to detect firefighter's falls, loss of physical performance, and alert high CO level by using a microcontroller carried by a firefighter with data fusion from a 3-DOF (degrees of freedom) accelerometer, 3-DOF gyroscope, 3-DOF magnetometer, barometer, and a MQ7 sensor using our proposed fall detection, loss of physical performance detection, and CO monitoring algorithms. By the combination of five sensors and highly efficient data fusion algorithms to observe the fall event, loss of physical performance, and detect high CO level, we can distinguish among falling, loss of physical performance, and the other on-duty activities (ODAs) such as standing, walking, running, jogging, crawling, climbing up/down stairs, and moving up/down in elevators. Signals from these sensors are sent to the microcontroller to detect fall, loss of physical performance, and alert high CO level. The proposed algorithms can achieve 100% of accuracy, specificity, and sensitivity in our experimental datasets and 97.96%, 100%, and 95.89% in public datasets in distinguishing between falls and ODAs activities, respectively. Furthermore, the proposed algorithm perfectly distinguishes between loss of physical performance and up/down movement in the elevator based on barometric data fusion. If a firefighter is unconscious following the fall or loss of physical performance, an alert message will be sent to their incident commander (IC) via the nRF224L01 module.
Abstract
Chitinases are enzymes that catalyze the degradation of chitin, a major component of the cell walls of pathogenic fungi and cuticles of insects, gaining increasing attention for the control ...of fungal pathogens and insect pests. Production of recombinant chitinase in a suitable host can result in a more pure product with less processing time and a significantly larger yield than that produced by native microorganisms. The present study aimed to express the synthetic chi42 gene (syncodChi42), which was optimized from the chi42 gene of Trichoderma asperellum SH16, in Escherichia coli to produce 42 kDa chitinase (Ta-CHI42); then determined the activity of this enzyme, characterizations and in vitro antifungal activity as well as its immunogenicity in mice. The results showed that Ta-CHI42 was overexpressed in E. coli. Analysis of the colloidal chitin hydrolytic activity of purified Ta-CHI42 on an agar plate revealed that this enzyme was in a highly active form. This is a neutral chitinase with pH stability in a range of 6–8 and has an optimum temperature of 45°C with thermal stability in a range of 25–35°C. The chitinolytic activity of Ta-CHI42 was almost completely abolished by 5 mM Zn2+ or 1% SDS, whereas it remained about haft under the effect of 1 M urea, 1% Triton X-100 or 5 mM Cu2+. Except for ions such as Mn2+ and Ca2+ at 5 mM that have enhanced chitinolytic activity; 5 mM of Na+, Fe2+ or Mg2+ ions or 1 mM EDTA negatively impacted the enzyme. Ta-CHI42 at 60 U/mL concentration strongly inhibited the growth of the pathogenic fungus Aspergillus niger. Analysis of western blot indicated that the polyclonal antibody against Ta-CHI42 was greatly produced in mice. It can be used to analyze the expression of the syncodChi42 gene in transgenic plants, through immunoblotting assays, for resistance to pathogenic fungi.
This study aims to express the synthetic chi42 gene encodes 42 kDa chitinase of T. asperellum in E. coli, determine the enzyme characterizations, antifungal activity and its immunogenesis in the mouse.
Chromoendoscopy and narrow-band imaging (NBI) have been reported to aid in the diagnosis of gastric intestinal metaplasia (GIM). This study aimed to assess the diagnostic validity of chromoendoscopy ...combined with NBI in the diagnosis of GIM in Vietnamese.
A cross-sectional study was carried out on patients with dyspeptic symptoms who underwent esophagogastroduodenoscopy (EGD) at the University Medical Center at Ho Chi Minh City. We compared the detection rates of GIM in the group of patients examined with white-light endoscopy (WLE) alone and those examined with WLE in combination with chromoendoscopy and NBI.
A total of 374 patients have been recruited. The additional GIM detection rate after chromoendoscopy combined with NBI was 8.6% (95% confidence interval CI: 4.3 − 12.8), p < .005. The rate of GIM within the group of patients biopsied under the guidance of chromoendoscopy combined with NBI was statistically significantly higher than in the group with WLE alone with a distinct rate of 14.4% (95% CI: 6.3 − 2.6), p = .001.
Chromoendoscopy combined with NBI helped to detect the GIM lesions missed by WLE and was a more reliable endoscopic method for the diagnosis of GIM.
•Properties of red mud in Vietnam's Tan Rai Alumina plant.•Dissolution ratio of SiO2 and Al2O3 in red mud, fly ash under different conditions.•Properties of red mud based alkali activated material ...after high temperature and autoclave curing.•Regression between the compressive strength and the total amount of dissolved SiO2.
To produce the alkali activated material, red mud must be used with components containing active silicon dioxide because silicon dioxide in red mud does not dissolve in alkaline solution. The test results presented in this paper show that high pressure and high temperature treatment in an autoclave can dissolve part of the silicone dioxide in red mud and improve the properties of material. The compressive strength of red mud based alkali activated materials can reach 10.6 MPa with a softening coefficient over 0.70. Adding an active silicon dioxide supplement by replacing 26.3 wt% red mud with fly ash increases the compressive strength up to 20 MPa and the softening coefficient by more than 0.90. Furthermore, autoclave treatment reduces residual sodium hydroxide and lowers the pH value of material. As the result, red mud based and red mud-fly ash based alkali activated materials can be used for manufacturing of masonry units.
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•A hybrid modified coordinate descent algorithm is proposed for LNG process.•An optimal design of SMR process is presented.•The compression energy for NG liquefaction is reduced up to ...44.3%.•The coefficient of performance (COP) of SMR cycle is improved up to 34.7%.•Exergy loss analysis of optimized SMR process is performed.
Design optimization of the single mixed refrigerant (SMR) natural gas liquefaction (LNG) process involves highly non-linear interactions between decision variables, constraints, and the objective function. These non-linear interactions lead to an irreversibility, which deteriorates the energy efficiency of the LNG process. In this study, a simple and highly efficient hybrid modified coordinate descent (HMCD) algorithm was proposed to cope with the optimization of the natural gas liquefaction process. The single mixed refrigerant process was modeled in Aspen Hysys® and then connected to a Microsoft Visual Studio environment. The proposed optimization algorithm provided an improved result compared to the other existing methodologies to find the optimal condition of the complex mixed refrigerant natural gas liquefaction process. By applying the proposed optimization algorithm, the SMR process can be designed with the 0.2555 kW specific compression power which is equivalent to 44.3% energy saving as compared to the base case. Furthermore, in terms of coefficient of performance (COP), it can be enhanced up to 34.7% as compared to the base case. The proposed optimization algorithm provides a deep understanding of the optimization of the liquefaction process in both technical and numerical perspectives. In addition, the HMCD algorithm can be employed to any mixed refrigerant based liquefaction process in the natural gas industry.
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•Novel hybrid configuration is proposed for debottlenecking of side stream column.•Significant saving in operating cost could be achieved.•A DWC can increase the energy efficiency of ...a heat pump.•A synergetic advantage of enhancing energy efficiency and reducing capital cost.•Can be applied to both close-boiling and wide-boiling mixtures.
Improving the energy efficiency of distillation columns and reducing the related CO2 emissions is a part of the global effort towards greater sustainability in chemical processing industries. Furthermore, increasing the capacity, which has been a major focus of the chemical process industry, can cause an entrainment flooding or a bottleneck problem in the distillation column. This paper reports the results of a techno-economic feasibility study to retrofit and debottleneck side stream columns, as one of most popular industrial distillation columns, in order to maximize energy efficiency and column throughput by using a novel hybrid configuration – heat pump assisted dividing wall column. The heat pump technique was used to improve the energy efficiency of a dividing wall column in debottlenecking a side stream column. On the other hand, the dividing wall column was exploited to increase the performance of a heat pump while also to removing bottlenecking problems. Several industrial cases were examined to demonstrate the proposed configuration. A heat pump assisted dividing wall column was optimized using a response surface methodology. The results showed that the proposed heat pump assisted dividing wall column can remove the bottleneck problem effectively and achieve substantial energy saving and CO2 emission reduction as well. Notably, an 83.7%, 85.9% and 61.3% reduction in operating costs could be achieved in the ethylene dichloride, acetic acid and alkanes separation processes, respectively. The proposed configuration can be applied to both close-boiling and wide-boiling mixtures, and also employed to both retrofit and grass-roots designs.
Background
Recently, transoral endoscopic thyroidectomy via the vestibular approach (TOETVA) has become popular worldwide.
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After controlling for the technique, the authors used the transoral ...endoscopic approach to modified radical neck dissection (MRND) for papillary thyroid carcinoma with clinically positive lymph nodes in the lateral compartments. To the best of their knowledge, the authors report the first case of TOETVA for MRND.
Patient
A 27-year-old woman had a diagnosis of cT1aN1bM0 right papillary thyroid carcinoma (metastatic to a small right level 4 lymph node). Therefore, total thyroidectomy, bilateral central neck dissection, and MRND of right levels 2, 3, and 4 were performed via the transoral endoscopic approach.
Methods
Total thyroidectomy and bilateral central lymph node dissections were performed based on the three-trocar Anuwong technique.
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Then, the fourth incision was made near the sixth teeth in the right oral vestibular area for insertion of the fourth 5-mm trocar, which was used to expose the lateral lymph compartment and to perform right MRND easily.
Results
The operation was completed successfully without conversion to open surgery. The total operative time was 170 min, and the operating time for MRND was 55 min. The numbers of harvested lymph nodes were 7 and 8 in the central and right lateral compartments, respectively. The numbers of metastatic lymph nodes were 2 and 1 in the central and lateral compartments, respectively. No major postoperative complications occurred.
Conclusion
Transoral endoscopic MRND of levels 2, 3, and 4 can be feasible and safe for highly selected patients.
Accurate neoplastic prediction can significantly decrease costs associated with pathology and unnecessary colorectal polypectomies. Narrow band imaging (NBI) and dual-focus (DF) mode are promising ...emerging optical technologies for recognizing neoplastic features of colorectal polyps digitally. This study aimed to clarify the clinical usefulness of NBI with and without DF assistance in the neoplastic prediction of small colorectal polyps (<10 mm).
This cross-sectional study included 530 small colorectal polyps from 343 consecutive patients who underwent colonoscopy at the University Medical Center from September 2020 to May 2021. Each polyp was endoscopically diagnosed in three successive steps using white-light endoscopy (WLE), NBI, and NBI-DF and retrieved for histopathological assessment. The diagnostic accuracy of each modality was evaluated with reference to histopathology.
There were 295 neoplastic polyps and 235 non-neoplastic polyps. The overall accuracies of WLE, WLE+NBI, and WLE+NBI+NBI-DF in the neoplastic prediction of colorectal polyps were 70.8%, 87.4%, and 90.8%, respectively (p<0.001). The accuracy of WLE+NBI+NBI-DF was significantly higher than that of WLE+NBI in the polyp size ≤5 mm subgroup (87.3% vs. 90.1%, p<0.001).
NBI improved the real-time neoplastic prediction of small colorectal polyps. The DF mode was especially useful in polyps ≤5 mm in size.
Background
Although transoral thyroidectomy has become popular in thyroid surgery, transoral robotic thyroidectomy (TORT) has only been successfully applied in a very small number of medical centers ...worldwide.
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In this video, we show a three-port TORT without an axillary incision for papillary thyroid carcinoma.
Patient and methods
A 35-year-old female with cT1aN0M0 papillary thyroid carcinoma had a strong motivation to proceed with surgery but avoid external neck incisions. Thus, we decided to perform a hemithyroidectomy with isthmusectomy using a transoral robotic approach, employing the da Vinci Xi surgical system.
Results
The operation was completed successfully without conversion to open surgery. The working space creation time, docking time, and console time were 30 min, 40 min, and 130 min, respectively. The pathological results were papillary thyroid carcinoma with 6- and 5-mm tumors. The patient was discharged 4 days after surgery without any complications such as bleeding, infection, mental nerve damage, permanent hoarseness, or hypoparathyroidism. The patient was completely satisfied with the cosmetic result.
Conclusion
Three-port TORT without an axillary incision is a promising approach with optimal cosmetic outcomes. For Vietnam, a developing country, success in the application of TORT using the new da Vinci Xi robotic platform for thyroid cancer is an important milestone in the development of thyroid surgery.
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