521 research outputs found

    Comparison of volume-controlled and pressure-controlled ventilation using a laryngeal mask airway during gynecological laparoscopy

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    Background: Several publications have reported the successful, safe use of Laryngeal Mask Airway (LMA)-Classic devices in patients undergoing laparoscopic surgery. However, there have been no studies that have examined the application of volume-controlled ventilation (VCV) or pressure-controlled ventilation (PCV) using a LMA during gynecological laparoscopy. The aim of this study is to compare how the VCV and PCV modes and using a LMA affect the pulmonary mechanics, the gas exchange and the cardiovascular responses in patients who are undergoing gynecological laparoscopy. Methods: Sixty female patients were randomly allocated to one of two groups, (the VCV or PCV groups). In the VCV group, baseline ventilation of the lung was performed with volume-controlled ventilation and a tidal volume of 10 ml/kg ideal body weight (IBW). In the PCV group, baseline ventilation of the lung using pressure-controlled ventilation was initiated with a peak airway pressure that provided a tidal volume of 10 ml/kg IBW and an upper limit of 35 cmH2O. The end-tidal CO2, the peak airway pressures (Ppeak), the compliance, the airway resistance and the arterial oxygen saturation were recorded at T1: 5 minutes after insertion of the laryngeal airway, and at T2 and T3: 5 and 15 minutes, respectively, after CO2 insufflation. Results: The Ppeak at 5 minutes and 15 minutes after CO2 insufflation were significantly increased compared to the baseline values in both groups. Also, at 5 minutes and 15 minutes after CO2 insufflation, there were significant differences of the Ppeak between the two groups. The compliance decreased in both groups after creating the pneumopertoneim (P < 0.05). Conclusions: Our results demonstrate that PCV may be an effective method of ventilation during gynecological laparoscopy, and it ensures oxygenation while minimizing the increases of the peak airway pressure after CO2 insufflation. ��� the Korean Society of Anesthesiologists, 2011

    Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3

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    How a certain ground state of complex physical systems emerges, especially in two-dimensional materials, is a fundamental question in condensed-matter physics. A particularly interesting case is systems belonging to the class of XY Hamiltonian where the magnetic order parameter of conventional nature is unstable in two-dimensional materials leading to a Berezinskii-Kosterlitz-Thouless transition. Here, we report how the XXZ-type antiferromagnetic order of a magnetic van der Waals material, NiPS3, behaves upon reducing the thickness and ultimately becomes unstable in the monolayer limit. Our experimental data are consistent with the findings based on renormalization group theory that at low temperatures a two-dimensional XXZ system behaves like a two-dimensional XY one, which cannot have a long-range order at finite temperatures. This work provides experimental examination of the XY magnetism in the atomically thin limit and opens new opportunities of exploiting these fundamental theorems of magnetism using magnetic van der Waals materials.Comment: 57 pages, 24 figures (including Supplementary Information

    Engineering PSU\u27s Future: An Interview with Dr. Rahmat Shoureshi

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    PSU’s ninth president, Dr. Rahmat Shoureshi (pronounced Shoe-re-she) is an experienced administrator and innovative academic who considers his work with students his greatest accomplishment. Shoureshi is a mechanical engineer who earned a master’s degree and a doctorate from the Massachusetts Institute of Technology. Shoureshi says PSU’s commitment to diversity, civic engagement and innovation persuaded him to join the university

    Polarity engineering in polycrystalline ZnO by inversion boundaries

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    Two distinctive polarity-engineered microstructures were obtained in polycrystalline ZnO ceramics by inducing two different types of inversion boundaries (IBs) inside individual grains to examine the effect of the different polarities on the varistor performances. The presence of head-to-head IBs induced by the addition of Sb and tail-to-tail IBs by doping Ti was directly confirmed by the characteristic geometry of the chemical etch pits. It was proposed that a consequent polarity on the grain boundary planes, which are affected by the presence of head-to-head IBs is crucial in exhibiting the superior performance of ZnO varistors.open2

    A randomized prospective trial of the postoperative quality of life between laparoscopic uterine artery ligation and laparoscopy-assisted vaginal hysterectomy for the treatment of symptomatic uterine fibroids: clinical trial design

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    <p>Abstract</p> <p>Background</p> <p>Laparoscopy-assisted vaginal hysterectomy is one of the definite methods for the treatment of symptomatic uterine fibroids with lesser intraoperative bleeding and shorter hospitalization compared with abdominal hysterectomy. However, laparoscopy-assisted vaginal hysterectomy cannot preserve uterus and can show postoperative complications by the change of pelvic structure. Thus, laparoscopic uterine artery ligation has been introduced for relieving the symptoms caused by uterine fibroids in place of hysterectomy. The current study was designed to compare postoperative quality of life between laparoscopic uterine artery ligation and laparoscopy-assisted vaginal hysterectomy, and to evaluate the efficacy of laparoscopic uterine artery ligation which can treat symptomatic uterine fibroids with the preservation of uterus.</p> <p>Methods and design</p> <p>Patients enrolled the current study are randomized to laparoscopic uterine artery ligation or laparoscopy-assisted vaginal hysterectomy. The primary outcome is to compare postoperative quality of life between laparoscopic uterine artery ligation and laparoscopy-assisted vaginal hysterectomy using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire for Cancer patients version 3.0. Secondary outcomes are to evaluate the volume reduction of uterus, uterine fibroids and ovaries by the 2 treatments, to compare the improvement of subjective symptoms using 11-point symptom score and postoperative clinical outcomes between laparoscopic uterine artery ligation and laparoscopy-assisted vaginal hysterectomy, and to investigate the improvement of postoperative vaginal bleeding by laparoscopic uterine artery ligation.</p> <p>Discussion</p> <p>Among treatment methods for symptomatic uterine fibroids with the preservation of uterus, laparoscopic uterine artery ligation is expected to have the efficacy like uterine artery embolization, which appeared to be safe for routine use with symptomatic relief. The current study fully recruited in June 2008 and the results will be available in June 2009. If there is no difference of postoperative QOL between laparoscopic uterine artery ligation and laparoscopy-assisted vaginal hysterectomy for the treatment of symptomatic uterine fibroids, the comparison of quality of life between laparoscopic uterine artery ligation and uterine artery embolization will be also needed as a surgical treatment for preserving uterus.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN76790866</p

    Developing a deep learning model for the simulation of micro-pollutants in a watershed

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    In recent years, as agricultural activities and types of crops have become diverse, the occurrence of micro-pollutants has been reported more frequently in rural areas. These pollutants have detrimental effects on human health and ecological systems; thus, it is important to manage and monitor their presence in the environment. The modeling approach could be an effective way to understand and manage these pollutants. This study predicts the concentrations of micro-pollutants (MPs) using deep learning (DL) models, and the results are then compared with simulation results obtained from the soil water assessment tool (SWAT) model. The SWAT model showed an unacceptable performance owing to the resulting negative NasheSutcliffe efficiency (NSE) values for the simulations. This may be caused by the limitations of SWAT, which pertains to adopting simplified equations to simulate micro-pollutants. In addition, the ambiguous plan of pesticide application increased the model uncertainty, thereby deteriorating the model result. Here, we developed two different DL models: long short-term memory (LSTM) and convolutional neural network (CNN). LSTM exhibited the highest model performance, with NSE values of 0.99 and 0.75 for the training and validation steps, respectively. In the multi-target MP model, the error decreased as the number of simulated pollutants increased. The simulation of the four pollutants had the highest error, while the six-target simulation had the lowest error. In conclusion, this study demonstrated that the LSTM model has the potential to improve the prediction of MPs in aquatic systems. (c) 2021 Elsevier Ltd. All rights reserved

    Post-radiation Piriformis Syndrome in a Cervical Cancer Patient -A Case Report-

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    The piriformis syndrome is a condition allegedly attributable to compression of the sciatic nerve by the piriformis muscle. Recently, magnetic resonance neurography and electrophysiologic study have helped to diagnose piriformis syndrome. High dose radiotherapy could induce acute and delayed muscle damage. We had experienced piriformis syndrome with fatty atrophy of piriformis muscle after radiotherapy for recurrent cervical cancer

    Primary Gastric Small Cell Carcinoma: A Case Identified as a Large Subepithelial Tumor from Invisible State in 6 Months

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    Primary gastric small cell carcinoma (GSCC) is one of the gastroenteropancreatic neuroendocrine tumors. It is a rare cancer with a very aggressive behavior and a poor prognosis because of the high rate of metastases. It is usually found in far advanced stage. We experienced a case of GSCC which had developed into a large subepithelial tumor (SET) from invisible state in a short period. A 65-year-old man consulted our hospital because of early gastric cancer. He underwent endoscopic submucosal dissection for the early gastric cancer at high body posterior wall. After 6 months, the follow-up endoscopy showed a large newly developed SET-like lesion with central ulceration at the gastric cardia. Endoscopic biopsy revealed GSCC. Total gastrectomy was performed. One out of the 26 perigastric lymph nodes had a metastasis. He received 6 cycles of adjuvant chemotherapy with etoposide and cisplatin. He is still in good health 12 months after operation

    Bidirectional Association Between Parkinson’s Disease and Obstructive Sleep Apnea: A Cohort Study

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    STUDY OBJECTIVES: Chronic intermittent hypoxia due to obstructive sleep apnea (OSA) causes oxidative stress, which may contribute to the pathophysiology of Parkinson\u27s disease (PD). However, the bidirectional relationship between PD and OSA has not been satisfactorily established. The objective of this study was to try to estimate whether there is a bidirectional relationship between PD and OSA through a retrospective cohort study in the South Korean population. METHODS: This study used data from the Korean National Health Information Database of the National Health Insurance Service, which contains data from 3.5 million individuals evenly distributed. In study 1, patients with OSA were matched in a 1:2 ratio with non-OSA controls. In study 2, patients with PD were matched in a 1:2 ratio with non-PD controls. A stratified Cox proportional hazards model was used to calculate hazard ratios. RESULTS: In study 1, which included 6,396 patients with OSA and 12,792 non-OSA controls, the incidence of PD per 10,000 person-years was 11.59 in the OSA group and 8.46 in the non-OSA group. The OSA group demonstrated a 1.54-fold higher incidence of PD than the non-OSA group (95% confidence interval, 1.14-2.07; CONCLUSIONS: This study supports a possible bidirectional relationship between PD and OSA. CITATION: Jeon S-H, Hwang YS, Oh S-Y, et al. Bidirectional association between Parkinson\u27s disease and obstructive sleep apnea: a cohort study
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