http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Modeling and Control of Integrated STATCOM-SMES System to Improve Power System Oscillations Damping
Molina, Marcelo G.,Mercado, Pedro E. The Korean Institute of Electrical Engineers 2008 Journal of Electrical Engineering & Technology Vol.3 No.4
Primary frequency control(PFC) has the ability to regulate short period random variations of frequency during normal operation conditions and also to respond rapidly to emergencies. However, during the past decade, numerous significant sized blackouts occurred worldwide that resulted in serious economic losses. Therefore, the conclusion has been reached that the ability of the current PFC to meet an emergency is poor, and security of power systems should be improved. An alternative to enhance the PFC and thus security is to store excessive amounts of energy during off-peak load periods in efficient energy storage systems for substituting the primary control reserve. In this sense, superconducting magnetic energy storage(SMES) in combination with a static synchronous compensator(STATCOM) is capable of supplying power systems with both active and reactive powers simultaneously and very rapidly, and thus is able to enhance the security dramatically. In this paper, a new concept of PFC based on incorporating a STATCOM-SMES is presented. A complete detailed model is proposed and a new control scheme is designed, comprising an enhanced frequency control scheme, and a fully decoupled current control strategy in d-q coordinates with a novel controller to prevent dc bus capacitors voltage drift/imbalance. The performance of the proposed control schemes is validated through digital simulation carried out using MATLAB/Simulink.
Molina, Mariana,Steinbach, Simone,Park, Young Mok,Yun, Su Yeong,Di Lorenzo Alho, Ana Tereza,Heinsen, Helmut,Grinberg, Lea T,Marcus, Katrin,Leite, Renata E Paraizo,May, Caroline Springer 2015 JOURNAL OF NEURAL TRANSMISSION Vol.122 No.7
<P>Brain function in normal aging and neurological diseases has long been a subject of interest. With current technology, it is possible to go beyond descriptive analyses to characterize brain cell populations at the molecular level. However, the brain comprises over 100 billion highly specialized cells, and it is a challenge to discriminate different cell groups for analyses. Isolating intact neurons is not feasible with traditional methods, such as tissue homogenization techniques. The advent of laser microdissection techniques promises to overcome previous limitations in the isolation of specific cells. Here, we provide a detailed protocol for isolating and analyzing neurons from postmortem human brain tissue samples. We describe a workflow for successfully freezing, sectioning and staining tissue for laser microdissection. This protocol was validated by mass spectrometric analysis. Isolated neurons can also be employed for western blotting or PCR. This protocol will enable further examinations of brain cell-specific molecular pathways and aid in elucidating distinct brain functions.</P>
E. Ferrer-Polonio,J.A. Mendoza-Roca,A. Iborra-Clar,J.L. Alonso-Molina,L. Pastor-Alcañiz 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.43 No.-
Biological treatment of hypersaline wastewaters such as fermentation brine from table olive processing(FTOP), was carried out using four sequential biological reactors (SBRs). These wastewaters werecharacterized by conductivities higher than 90 mS cm 1 together with COD and total phenolsconcentration values of more than 15 g L 1 and 1000 mg L 1, respectively. In order to increase theorganic removal efficiency and to reduce the hydraulic retention time (HRT), extra nutrients were addedand pre-treatment by adsorption was performed. Results showed that the COD/N/P relationship, in theFTOP, of 250/5/1 was appropriate for the biological process reaching COD removal efficiencies of around80%. The FTOP adsorption pre-treatment with powder activated carbon for the reduction of phenolsconcentration to 400 mg L 1 led to a HRT reduction from 40 to 15 days, maintaining the COD and totalphenols removal percentages around 78% and 97%, respectively. On the other hand, g-Proteobacteria wasthe main bacterial class, representing around 74% of the microbial community in the reactors.
Modeling and Control of Integrated STATCOM-SMES System to Improve Power System Oscillations Damping
Marcelo G. Molina,Pedro E. Mercado 대한전기학회 2008 Journal of Electrical Engineering & Technology Vol.3 No.4
Primary frequency control (PFC) has the ability to regulate short period random variations of frequency during normal operation conditions and also to respond rapidly to emergencies. However, during the past decade, numerous significant sized blackouts occurred worldwide that resulted in serious economic losses. Therefore, the conclusion has been reached that the ability of the current PFC to meet an emergency is poor, and security of power systems should be improved. An alternative to enhance the PFC and thus security is to store excessive amounts of energy during off-peak load periods in efficient energy storage systems for substituting the primary control reserve. In this sense, superconducting magnetic energy storage (SMES) in combination with a static synchronous compensator (STATCOM) is capable of supplying power systems with both active and reactive powers simultaneously and very rapidly, and thus is able to enhance the security dramatically. In this paper, a new concept of PFC based on incorporating a STATCOM-SMES is presented. A complete detailed model is proposed and a new control scheme is designed, comprising an enhanced frequency control scheme, and a fully decoupled current control strategy in d-q coordinates with a novel controller to prevent de bus capacitors voltage drift/imbalance. The performance of the proposed control schemes is validated through digital simulation carried out using MATLAB/Simulink.
Young capillary vessels rejuvenate aged pancreatic islets
Almaca, Joana,Molina, Judith,Arrojo e Drigo, Rafael,Abdulreda, Midhat H.,Jeon, Won Bae,Berggren, Per-Olof,Caicedo, Alejandro,Nam, Hong Gil National Academy of Sciences 2014 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.111 No.49
<P><B>Significance</B></P><P>The regulation of blood glucose is a homeostatic process that declines with age, but it is unknown whether this disturbance is a consequence of intrinsic dysfunction of the regulatory organ, the pancreatic islet. In marked contrast to the widely held notion that the insulin-producing pancreatic beta cell loses function with wear and tear, and thus causes age-related disturbances in glucose homeostasis, we show that mouse and human beta cells are fully functional at advanced age. The pancreatic islet as an organ, however, is threatened by vascular senescence. Replacing the islet vasculature in aged islet grafts rejuvenates the islet and fully restores glucose homeostasis, indicating that islet blood vessels should be targeted to mitigate frail glucose homeostasis associated with aging.</P><P>Pancreatic islets secrete hormones that play a key role in regulating blood glucose levels (glycemia). Age-dependent impairment of islet function and concomitant dysregulation of glycemia are major health threats in aged populations. However, the major causes of the age-dependent decline of islet function are still disputed. Here we demonstrate that aging of pancreatic islets in mice and humans is notably associated with inflammation and fibrosis of islet blood vessels but does not affect glucose sensing and the insulin secretory capacity of islet beta cells. Accordingly, when transplanted into the anterior chamber of the eye of young mice with diabetes, islets from old mice are revascularized with healthy blood vessels, show strong islet cell proliferation, and fully restore control of glycemia. Our results indicate that beta cell function does not decline with age and suggest that islet function is threatened by an age-dependent impairment of islet vascular function. Strategies to mitigate age-dependent dysregulation in glycemia should therefore target systemic and/or local inflammation and fibrosis of the aged islet vasculature.</P>
Neural Mechanisms in Eating Behaviors: A Pilot fMRI Study of Emotional Processing
Rosa M. Molina-Ruiz,T. García-Saiz,Jeffrey C.L. Looi,E. Via Virgili,M. Rincón Zamorano,Laura de Anta Tejado,Helena Trebbau López,Jose Luis Carrasco Perera,Marina Díaz-Marsá 대한신경정신의학회 2020 PSYCHIATRY INVESTIGATION Vol.17 No.3
Objective Emotional processing dysfunction evident in eating disorders (ED) such as anorexia nervosa (AN) and bulimia nervosa (BN), is considered relevant to the development and maintenance of these disorders. The purpose of the current functional magnetic resonance imaging (fMRI) study was to pilot a comparison of the activity of the fronto-limbic and fronto-striatal brain areas during an emotion processing task in persons with ED. Methods 24 women patients with ED were scanned, while showing emotionally stimulating (pleasant, unpleasant) and neutral images from the International Affective Picture System (IAPS). Results During the pleasant condition, significant differences in Dorsolateral Prefrontal Cortex (DLPFC) activations were found with AN participants presenting greater activation compared to BN and ED comorbid groups (EDc) and healthy controls also showing greater activation of this brain area compared to BN and EDc. Left putamen was less activated in EDc compared to both controls (C) and AN. During the unpleasant condition, AN participants showed hyperactivation of the Orbito-Frontal Cortex (OFC) when compared to EDc. Conclusion This study highlights the potential functional relevance of brain areas that have been associated with self-control. These findings should help advance understanding the neural substrate of ED, though they should be considered as preliminary and be cautiously interpreted.
Ben H. Chew,구교철,Abdulghafour Halawani,Colin J. Lundeen,Bodo E. Knudsen,Wilson R. Molina 대한비뇨의학회 2023 Investigative and Clinical Urology Vol.64 No.3
Purpose: Holmium:YAG laser lithotripsy requires high amperage power and has an upper limit of frequency and a minimal fiber size. The technology utilizing thulium-doped fiber offers low pulse energy settings and high pulse frequencies up to 2,400 Hz. We compared the novel SuperPulsed thulium fiber laser (SOLTIVE™; Olympus) to a commercially available 120 W Ho:YAG laser. Materials and Methods: Bench-top testing was conducted with 125 mm3 standardized BegoStones (Bego USA). Time to ablate the stone into particles <1 mm was recorded for efficiency calculations. Finite energy was delivered, and resulting particle sizes were measured to determine fragmentation (0.5 kJ) and dusting (2 kJ) efficiencies. Remaining mass or number of fragments were measured to compare efficacy. Results: SOLTIVE™ was faster at ablating stones to particles <1 mm (2.23±0.22 mg/s, 0.6 J 30 Hz short pulse) compared to Ho:YAG laser (1.78±0.44 mg/s, 0.8 J 10 Hz short pulse) (p<0.001). Following 0.5 kJ of energy in fragmentation testing, fewer particles >2 mm remained using SOLTIVE™ than Ho:YAG laser (2.10 vs. 7.20 fragments). After delivering 2 kJ, dusting (1.05±0.08 mg/s) was faster using SOLTIVE™ (0.1 J 200 Hz short pulse) than 120 W 0.46±0.09 mg/s (0.3 J 70 Hz Moses) (p=0.005). SOLTIVE™ (0.1 J 200 Hz) produced more dust particles <0.5 mm (40%) compared to 24% produced by the P120 W laser at 0.3 J 70 Hz Moses and 14% at 0.3 J 70 Hz long pulse (p=0.015). Conclusions: The efficacy of SOLTIVE™ is superior to the 120 W Ho:YAG laser by producing smaller dust particles and fewer fragments. Further studies are warranted.
Right-sided acute diverticulitis in the West: experience at a university hospital in Argentina
Huatuco René M. Palacios,Pachajoa Diana A. Pantoja,Liaño Julian E.,Molina Héctor A. Picón,Palencia Rafael,Doniquian Alejandro M.,Parodi Matías 대한대장항문학회 2023 Annals of Coloproctolgy Vol.39 No.2
Purpose: In the West, diverticular disease is located mainly in the left colon. However, it can also present in the right colon, with an incidence of 1%–2% in Caucasians. The purpose of this study was to describe our experience in right-sided acute diverticulitis (RD). Methods: In this retrospective study, 410 patients with acute diverticulitis treated from 2013 to 2020 were included in a university hospital in Córdoba, Argentina. Colonic diverticulitis was stratified into 2 groups; RD and left-sided acute diverticulitis. Demographic and clinical variables, laboratory and imaging findings, type of treatment, follow-up, and recurrence were analyzed. Results: Sixteen patients (3.9%) with RD were identified; 62.5% were male and the mean age was 40.7±11.7 years. A total of 81.3% were Caucasian and 18.7% Native American. Significant differences were found between both groups of diverticulitis; patients with RD were younger (P=0.001), with lower BMI (P=0.01), comorbidity rate (P=0.01), Charlson comorbidity index (P=0.02), hospital stay (P=0.01), severity according to the Hinchey classification (P=0.001) and had a lower recurrence rate (P=0.001). There were no significant differences in sex (P=0.95), duration of pain until admission (P=0.05), laboratory findings (P=0.23) and treatment (P=0.34). Conclusion: Conservative treatment predominated in RD, with a lower rate of complications and recurrences, providing data that support conservative therapy as initial treatment in RD in our environment.