36 research outputs found
The Challenges of Drone ApplicationĂÂ in the Construction Industry
Drone technology is currently being used in many areas, and the increasing prevalence of drones is evident in all areas. Drones were first used for military purposes and now they have become an important part of military actions. In recent years, drone technology has become widespread in various industries including journalism, filmmaking, aerial photography, shipping, delivery. However, drone technology is still in its infancy and has not had a significant impact on the construction industry in Malaysia. Therefore, the study's objective was to assess the challenges preventing the application of drone technology in the Malaysian construction industry. The methodology used for this research was qualitative, which is data collection through interviews with three drone experts. The respondents in this research were directors of construction companies that use unmanned aerial vehicles for their operations. The findings showed that drones faced the challenges of unfamiliarity, lack of knowledge, reticence to adopt new technologies, privacy issues, and security issues. These challenges faced by drone technology will not prevent its application in the Malaysian construction industry. However, Government support is important in promoting the use of drone technology and raising people's awareness of drone technology in the construction industry
CO2 Capture and Crystallization of Ammonia Bicarbonate in a Lab-Scale Scrubber
A lab-scale bubble-column scrubber is used to capture CO2 gas and produce ammonia bicarbonate (ABC) using aqueous ammonia as an absorbent under a constant pH and temperature. The CO2 concentration is adjusted by mixing N2 and CO2 in the range of 15â60 vol % at 55 °C. The process variables are the pH of the solution, temperature, gas-flow rate and the concentration of gas. The effects of the process variables on the removal efficiency (E), absorption rate (RA) and overall mass-transfer coefficient (KGa) were explored. A multiple-tube mass balance model was used to determine RA and KGa, in which RA and KGa were in the range of 2.14 Ă 10â4â1.09 Ă 10â3 mol/(s·L) and 0.0136â0.5669 1/s, respectively. Results found that, RA showed an obvious increase with the increase in pH, inlet gas concentration and gas temperature, while KGa decreased with an increase in inlet gas concentration. Using linear regression, an empirical expression for KGa/E was obtained. On the other hand, ammonia bicarbonate crystals could be produced at a pH of 9.5 when the gas concentration was higher than 30% and Îł (=Fg/FA, the gas-liquid molar flow rate ratio) â„ 1.5
Cobalt-Catalyzed Highly Regio- and Stereoselective Intermolecular Reductive Coupling of Alkynes with Conjugated Alkenes
IGF-axis confers transformation and regeneration of fallopian tube fimbria epithelium upon ovulationResearch in context
Background: The fallopian tube fimbria is regarded as the main tissue of origin and incessant ovulation as the main risk factor of ovarian high-grade serous carcinoma. Previously, we discovered the tumorigenesis activity of human ovulatory follicular fluid (FF) upon injection to the mammary fat pad of Trp53-null mice. We also found a mutagenesis activity of FF-ROS and a apoptosis-rescuing activity of Hb from retrograde menstruation. However, neither of them can explain the tumorigenesis activities of FF. Methods: From two cohorts of ovulatory FF retrieved from IVF patients, the main growth factor responsible for the transformation of human fimbrial epithelial cells was identified. Mechanism of activation, ways of signal transduction of the growth factor, as well as the cellular and genetic phenotypes of the malignant transformation was characterized. Findings: In this study, we showed that insulin-like growth factor (IGF)-axis proteins, including IGFBP-bound IGF2 as well as the IGFBP-lytic enzyme PAPP-A, are abundantly present in FF. Upon engaging with glycosaminoglycans on the membrane of fimbrial epithelial cells, PAPP-A cleaves IGFBPs and releases IGF2 to bind with IGF-1R. Through the IGF-1R/AKT/mTOR and IGF-1R/AKT/NANOG pathways, FF-IGF leads to stemness and survival, and in the case of TP53/Rb or TP53/CCNE1 loss, to clonal expansion and malignant transformation of fimbrial epithelial cells. By depleting each IGF axis component from FF, we proved that IGF2, IGFBP2/6, and PAPP-A are all essential and confer the majority of the transformation and regeneration activities. Interpretation: This study revealed that the FFâIGF axis functions to regenerate tissue damage after ovulation and promote the transformation of fimbrial epithelial cells that have been initiated by p53- and Rb-pathway disruptions. Fund: The study was supported by grants of the Ministry of Science and Technology, Taiwan (MOST 106-2314-B-303-001-MY2; MOST 105-2314-B-303-017-MY2; MOST 107-2314-B-303-013-MY3), and Buddhist Tzu Chi General Hospital, Taiwan (TCMMP104-04-01). Keywords: Ovarian high-grade serous carcinoma, Follicular fluid, Fallopian tube fimbriae, IGF axis, Stemnes
Clinical experience of large colorectal laterally spreading tumor in a regional hospital: 2-year results
Background: Nonpolypoid colorectal neoplasm has been widely recognized in the past few years. Among nonpolypoid colorectal neoplasms, laterally spreading tumor (LST) is a unique and distinct category in that the tumor grows horizontally with a size >1 cm. It may be easily overlooked during colonoscopy. If the size of the colorectal LST is >2 cm, achieving definite management is also another concerning issue. The aim of this study was to improve our understanding of LST by reviewing its clinical manifestations.
Methods: All the large colorectal LSTs that were diagnosed and managed at our hospital in the past 2 years were reviewed. Basic demographic data were recorded. LSTs were divided into granular (G) and nongranular types (NG), then further subdivided into nodular mixed and homogeneous types for the G group and flat elevated and pseudodepressed types for the NG group.
Results: A total of 28 LST in 28 patients were enrolled, with males being more predominant than females (male/female: 18/10). Mean age of the patients and mean size of the LST were 62.6 ± 9.75 years and 3.4 ± 1.257 cm, respectively. Concerning morphology, 14 were diagnosed as NG and 14 as G group. The rate of malignant change was 28.6% (8/28). Twenty-three of our patients received endoscopic treatment (5 for endoscopic piecemeal mucosal resection 18 for endoscopic submucosal dissection) and five for laparoscopy-assisted colectomy. The cost and length of admission analysis between the endoscopic and operation treatment groups showed significant cost reduction (endoscopy/operation: NTD 28172/82516, p < 0.001) and fewer admission days in the endoscopy therapy group (4.74/9.00, days, p < 0.001). Subgroup comparison between the G and NG groups did not reveal statistical significance in age, sex ratio, tumor size, rate of malignant change, or location.
Conclusion: Although long-term outcome comparison was lacking, endoscopic treatment should be considered firstly for colorectal LST under the consideration of shorter hospitalization. Most of our analyses between the G and NG groups were statistically insignificant, which is likely to be due to the small population base
Clinical experience of large colorectal laterally spreading tumor in a regional hospital: 2-year results
Nonpolypoid colorectal neoplasm has been widely recognized in the past few years. Among nonpolypoid colorectal neoplasms, laterally spreading tumor (LST) is a unique and distinct category in that the tumor grows horizontally with a size >1 cm. It may be easily overlooked during colonoscopy. If the size of the colorectal LST is >2 cm, achieving definite management is also another concerning issue. The aim of this study was to improve our understanding of LST by reviewing its clinical manifestations. All the large colorectal LSTs that were diagnosed and managed at our hospital in the past 2 years were reviewed. Basic demographic data were recorded. LSTs were divided into granular (G) and nongranular types (NG), then further subdivided into nodular mixed and homogeneous types for the G group and flat elevated and pseudodepressed types for the NG group. A total of 28 LST in 28 patients were enrolled, with males being more predominant than females (male/female: 18/10). Mean age of the patients and mean size of the LST were 62.6 ± 9.75 years and 3.4 ± 1.257 cm, respectively. Concerning morphology, 14 were diagnosed as NG and 14 as G group. The rate of malignant change was 28.6% (8/28). Twenty-three of our patients received endoscopic treatment (5 for endoscopic piecemeal mucosal resection 18 for endoscopic submucosal dissection) and five for laparoscopy-assisted colectomy. The cost and length of admission analysis between the endoscopic and operation treatment groups showed significant cost reduction (endoscopy/operation: NTD 28172/82516, p < 0.001) and fewer admission days in the endoscopy therapy group (4.74/9.00, days, p < 0.001). Subgroup comparison between the G and NG groups did not reveal statistical significance in age, sex ratio, tumor size, rate of malignant change, or location. Although long-term outcome comparison was lacking, endoscopic treatment should be considered firstly for colorectal LST under the consideration of shorter hospitalization. Most of our analyses between the G and NG groups were statistically insignificant, which is likely to be due to the small population base
Regulation of Androgen Receptor and Prostate Cancer Growth by Cyclin-dependent Kinase 5
Prostate cancer is the most frequently diagnosed male malignancy. The normal prostate development and prostate cancer progression are mediated by androgen receptor (AR). Recently, the roles of cyclin-dependent kinase 5 (Cdk5) and its activator, p35, in cancer biology are explored one after another. We have previously demonstrated that Cdk5 may regulate proliferation of thyroid cancer cells. In addition, we also identify that Cdk5 overactivation can be triggered by drug treatments and leads to apoptosis of prostate cancer cells. The aim of this study is to investigate how Cdk5 regulates AR activation and growth of prostate cancer cells. At first, the data show that Cdk5 enables phosphorylation of AR at Ser-81 site through direct biochemical interaction and, therefore, results in the stabilization of AR proteins. The Cdk5-dependent AR stabilization causes accumulation of AR proteins and subsequent activation. Besides, the positive regulations of Cdk5-AR on cell growth are also determined in vitro and in vivo. S81A mutant of AR diminishes its interaction with Cdk5, reduces its nuclear localization, fails to stabilize its protein level, and therefore, decreases prostate cancer cell proliferation. Prostate carcinoma specimens collected from 177 AR-positive patients indicate the significant correlations between the protein levels of AR and Cdk5 or p35. These findings demonstrate that Cdk5 is an important modulator of AR and contributes to prostate cancer growth. Therefore, Cdk5-p35 may be suggested as diagnostic and therapeutic targets for prostate cancer in the near future
Exposure to phthalates impaired neurodevelopment through estrogenic effects and induced DNA damage in neurons
© 2020 The Authors Phthalates are commonly used in plastic products in daily life. The endocrine-disrupting effects of phthalates have been widely reported. Accumulating evidence from human cohorts and lab animals indicate exposure to phthalates might impair neurodevelopment. However, the direct causal relationship and mechanism between phthalates with neurodevelopment and neurotoxicity have not been firmly established. We found that phthalates (i.e. DBP, DINP, BBP) disrupted the expression of estrogen receptors (esr1, esr2a, esr2b), and impaired neurogenesis in the brain of zebrafish during embryonic development. Moreover, the abnormal expression of estrogen receptors, especially esr2a, was partly rescued in zebrafish which exposed to phthalates, with the estrogen receptor antagonist tamoxifen. Hence, impaired neurogenesis of zebrafish exposed to phthalates was partly reversed by tamoxifen treatment. Moreover, our results show that induced pluripotent stem cells (iPSC)-derived human neurons exposed to phthalates triggered double-strand DNA breaks in vitro. Overall, this study demonstrates that exposure to phthalates affects neurodevelopment in zebrafish embryos and induces neurotoxicity in human neurons partly through disrupting the expression of estrogen receptors
Navigation-Assisted One-Staged Posterior Spinal Fusion Using Pedicle Screw Instrumentation in Adolescent Idiopathic ScoliosisâA Case Series
Background and Objectives: Adolescent idiopathic scoliosis (AIS) is a prevalent three-dimensional spinal disorder, with a multifactorial pathogenesis, including genetics and environmental aspects. Treatment options include non-surgical and surgical treatment. Surgical interventions demonstrate positive outcomes in terms of deformity correction, pain relief, and improvements of the cardiac and pulmonary function. Surgical complications, including excessive blood loss and neurologic deficits, are reported in 2.27â12% of cases. Navigation-assisted techniques, such as the O-arm system, have been a recent focus with enhanced precision. This study aims to evaluate the results and complications of one-stage posterior instrumentation fusion in AIS patients assisted by O-arm navigation. Materials and Methods: This retrospective study assesses 55 patients with AIS (12â28 years) who underwent one-stage posterior instrumentation correction supported by O-arm navigation from June 2016 to August 2023. We examined radiological surgical outcomes (initial correction rate, loss of correction rate, last follow-up correction rate) and complications as major outcomes. The characteristics of the patients, intraoperative blood loss, operation time, number of fusion levels, and screw density were documented. Results: Of 73 patients, 55 met the inclusion criteria. The average age was 16.67 years, with a predominance of females (78.2%). The surgical outcomes demonstrated substantial initial correction (58.88%) and sustained positive radiological impact at the last follow-up (56.56%). Perioperative complications, including major and minor, occurred in 18.18% of the cases. Two patients experienced a major complication. Blood loss (509.46 mL) and operation time (402.13 min) were comparable to the literature ranges. Trend analysis indicated improvements in operation time and blood loss over the study period. Conclusions: O-arm navigation-assisted one-stage posterior instrumentation proves reliable for AIS corrective surgery, achieving significant and sustained positive radiological outcomes, lower correction loss, reduced intraoperative blood loss, and absence of implant-related complications. Despite the challenges, our study demonstrates the efficacy and maturation of this surgical approach