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Over time, predictive models tend to become more accurate but also more complex, thus achieving better predictive accuracy. When the data is improved by increasing its quantity and availability, the models are also better, which implies that the data must be processed to filter and adapt it for initial analysis and then modeling. This work aims to apply the Random Forest model to predict PM10 particles. For this purpose, data were obtained from environmental monitoring stations in Mexico City, which operates 29 stations of which 12 belong to the State of Mexico. The pollutants analyzed were CO carbon monoxide, NO nitrogen oxide, and PM10 particulate matter equal to or less than 10 µg.m-3, NOx nitrogen oxide, NO2 nitrogen dioxide, SO2 sulfur dioxide, O3 ozone, and PM2.5 particulate matter equal to or less than 2.5 µg.m-3. The result was that when calculating the certainty of our model, we have a value of 80.40% when calculating the deviation from the mean, using 15 reference variables. [ABSTRACT FROM AUTHOR]

Copyright of Revista CES Derecho is the property of Universidad CES and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Inguinal lymph node dissection (ILND) plays an important role for both staging and treatment purposes in patients diagnosed with penile carcinoma (PeCa). Video–endoscopic inguinal lymphadenectomy (VEIL) has been introduced to reduce complications, and in those patients elected for bilateral ILND, a simultaneous bilateral VEIL (sB-VEIL) has also been proposed. This study aimed to investigate the feasibility, safety, and preliminary oncological outcomes of sB-VEIL compared to consecutive bilateral VEIL (cB-VEIL). Material and methods: Clinical N0-2 patients diagnosed with PeCa and treated with cB-VEIL and sB-VEIL between 2015 and 2023 at our institution were included. Modified ILND was performed in cN0 patients, while cN+ patients underwent a radical approach. Intra- and postoperative complications, operative time, time of drainage maintenance, length of hospital stay and readmission within 90 days, as well as lymph node yield, were compared between the two groups. Results: Overall, 30 patients were submitted to B-VEIL. Of these, 20 and 10 patients underwent cB-VEIL and sB-VEIL, respectively. Overall, 16 (80%) and 7 (70%) patients were submitted to radical ILND due to cN1-2 disease in the cB-VEIL and sB-VEIL groups, respectively. No statistically significant difference emerged in terms of median nodal yield (13.5 vs. 14, p = 0.7) and median positive LNs (p = 0.9). sD-VEIL was associated with a shorter operative time (170 vs. 240 min, p < 0.01). No statistically significant difference emerged in terms of intraoperative estimated blood loss, length of hospital stay, time to drainage tube removal, major complications, and hospital readmission in the cB-VEIL and sB-VEIL groups, respectively (all p > 0.05). Conclusions: Simultaneous bilateral VEIL is a feasible and safe technique in patients with PeCA, showing similar oncological results and shorter operative time compared to a consecutive bilateral approach. Patients with higher preoperative comorbidity burden or anesthesiological risk are those who may benefit the most from this technique. [ABSTRACT FROM AUTHOR]

Purpose: To provide a new model to predict long-term renal function impairment after partial nephrectomy (PN). Methods: Data of consecutive patients who underwent minimally invasive PN from 2005 to 2022 were analyzed. A minimum of 12 months of follow-up was required. We relied on a machine-learning algorithm, namely classification and regression tree (CART), to identify the predictors and associated clusters of chronic kidney disease (CKD) stage migration during follow-up. Results: 568 patients underwent minimally invasive PN at our center. A total of 381 patients met our inclusion criteria. The median follow-up was 69 (IQR 38–99) months. A total of 103 (27%) patients experienced CKD stage migration at last follow-up. Progression of CKD stage after surgery, ACCI and baseline CKD stage were selected as the most informative risk factors to predict CKD progression, leading to the creation of four clusters. The progression of CKD stage rates for cluster #1 (no progression of CKD stage after surgery, baseline CKD stage 1–2, ACCI 1–4), #2 (no progression of CKD stage after surgery, baseline CKD stage 1–2, ACCI ≥ 5), #3 (no progression of CKD stage after surgery and baseline CKD stage 3–4–5) and #4 (progression of CKD stage after surgery) were 6.9%, 28.2%, 37.1%, and 69.6%, respectively. The c-index of the model was 0.75. Conclusion: We developed a new model to predict long-term renal function impairment after PN where the perioperative loss of renal function plays a pivotal role to predict lack of functional recovery. This model could help identify patients in whom functional follow-up should be intensified to minimize possible worsening factors of renal function. [ABSTRACT FROM AUTHOR]

Copyright of REDER: Revista de Estudios Latinoamericanos sobre Reducción del Riesgo de Desastres is the property of Corporacion Gestion de Riesgos y Desastres (GRID-Chile) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Robots executing contact tasks are essential in a wide range of industrial processes such as polishing, welding, debugging, drilling, etc. Force control is indispensable in these type of tasks since it is required to keep the interaction force (between the robot and the environment/surface) within acceptable values. In this paper, we present a methodology to analyze and to design the force control system needed to regulate the force as close as possible to the desired value. The proposed methods are presented using a widely used generic contact task consisting of exerting a desired force on the normal direction to the surface while a desired velocity/position is tracked on the tangent direction to the surface. The analysis considers environments/surfaces with certain uneven characteristics, i.e., not perfectly flat. The uneven characteristic is studied using ramp or sinusoidal signals disturbing the position on the normal direction to the surface, and we present how the velocity on the tangent direction is related with the slope of the ramp or the frequency of the sinusoidal disturbance. Then, we provide a method to design the force controller that keeps the force error within desired limits and preserves stability, despite the uneven surface. Furthermore, considering the relation between the disturbance (ramp or sinusoidal) and the tangent velocity, we present a method to compute the maximum velocity for which the task can be executed. Simulations exemplifying and verifying the proposed methods are presented. [ABSTRACT FROM AUTHOR]

Purpose: To identify preoperative predictors of endo-urological treatment (EUT) failure while promoting a new diagnostic and therapeutic pathway for benign uretero-enteric anastomosis stricture (UES) management after radical cystectomy (RC). Materials and methods: We relied on a prospectively maintained database including 96 individuals (122 renal units) who developed a benign UES at our institution between 1990 and 2018. UES was classified into two different types according to morphology: FP1 (i.e., sharp or duckbill) and FP2 (i.e., flat or concave). EUT feasibility, success rate, as well as intra and postoperative complications were recorded. Uni- and multivariable logistic regression analysis (MVA) assessed for predictors of EUT failure. Results: Overall, 78 (63.9%) and 32 (26.3%) cases were defined as FP1 and FP2, respectively. EUT was not feasible in 33 (27.1%) cases. After a median follow-up of 50 (IQR 5–240) months, successful treatment was reached only in 15/122 (12.3%) cases. EUT success rates raised when considering short (< 1 cm) (16.8%), FP1 morphology (16.7%) strictures, or the combination of these characteristics (22.4%). Overall, 5 (5.2%) cases had CD ≥ III complications. FP2 (OR: 1.91, 95%CI 1.21–5.31, p = 0.03) and stricture length ≥ 1 cm (OR: 9.08, 95%CI 2.09–65.71, p = 0.009) were associated with treatment failure at MVA. Conclusions: Endoscopic treatment for benign UES after RC is feasible but harbors a low success rate. Stricture length and radiological morphology of the stricture are related to endoscopic treatment failure. Surgeons should be aware of the stricture features during the preoperative decision-making process to choose the optimal candidate for endoscopic treatment. [ABSTRACT FROM AUTHOR]

Copyright of REMIE - Multidisciplinary Journal of Educational Research is the property of Hipatia Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The presence of distributed generators (DGs) based on renewable energy is a fact in the electrical grid. However, DGs based on renewable resources such as photovoltaic panels and storage systems lack inertia, which is used by synchronous generators to compensate oscillations in the electrical grid. Thus, virtual inertia is introduced via a virtual synchronous generator (VSG) scheme. Although VSG is widely used, its robustness cannot be ensured since it employs proportional–integral–derivative‐type (PID‐type) controllers, which are sensitive to parameters variations. Furthermore, PID‐type controllers are designed assuming balance conditions and the negative sequence components produced during unbalanced conditions are not considered. This paper proposes a robust VSG topology working under unbalanced conditions. A sliding mode control (SMC) algorithm named super‐twisting (ST) is integrated into the control loop of VSG providing insensitivity to matched disturbances/uncertainties and finite‐time convergence. Since the design of the ST algorithm considers the presence of negative‐sequence components, it is not necessary a modification of the control loop before, during, or after the fault. The method to compute the ST control gains and the stability test using Lyapunov are provided. The VSG scheme is tested via simulations, where voltage sags are applied to generate the unbalanced conditions. [ABSTRACT FROM AUTHOR]

A concept of the practical stability margins for systems driven by finite-time convergent (FTC) controllers, including sliding-mode/higher order sliding-mode (HOSM) controllers, is proposed. These margins are based on the system's tolerance to self-sustained oscillations with certain amplitude and frequency limits. The practical stability margins are introduced as the maximal gain increase or/and the maximal phase lag added to the frequency characteristic of the linear part of the open-loop system that yields acceptable loss of system's stability/performance in terms of admissible parameters of self-sustaining oscillations. It is proposed using the describing function-harmonic balance technique for the identification of the practical stability margins. To ensure the desired practical stability margins, linear dynamics compensators are designed and added in cascade to FTC controllers. The proposed approach is verified on numerous examples. [ABSTRACT FROM AUTHOR]

In this paper, the conventional aircraft control system certification approach based on phase margin (PM) and gain margin (GM) is extended to higher order sliding mode (HOSM) controllers. The proposed practical stability PM (PSPM) and the practical stability GM (PSGM) are used to quantify the HOSM control system robustness to unmodeled dynamics. The tools/algorithms for the identification of PSPM and PSGM are developed using describing function-harmonic balance method. A design algorithm of a cascade dynamic compensator for a dynamically perturbed HOSM control system is presented and can be used to satisfy required practical stability margins. The theoretical developments are illustrated and validated on controlling the attitude of an F-16 aircraft. [ABSTRACT FROM AUTHOR]

Copyright of Universitas Psychologica is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Profesorado: Revista de Currículum y Formación del Profesorado is the property of Profesorado: Revista de Curriculum y Formacion del Profesorado and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Doubly fed induction generators (DFIGs) are widely used in variable-speed wind turbines. Despite the well-accepted performance of DFIGs, these generators are highly sensible to grid faults. Hence, the presence of grid faults must be considered in the design of any control system to be deployed on DFIGs. Sliding mode control (SMC) is a useful alternative for electric machinery control since SMC offers fast dynamic response and less sensitivity to parameter variations and disturbances. Additionally, the natural outputs of SMC are discontinuous signals allowing direct switching of power electronic devices. In this paper, a grid-voltage-oriented SMC is proposed and tested under low voltage grid faults. Unlike other nonmodulated techniques such as direct torque control, there is not a necessity of modifying the controller structure for withstanding low depth voltage dips. For stator natural flux cancelation, the torque and reactive power references are modified to inject a demagnetizing current. Simulation results demonstrate the demagnetization of the natural flux component as well as a robust tracking control under balanced and unbalanced voltage dips. [ABSTRACT FROM AUTHOR]

Copyright of Global Social Work / Trabajo Social Global is the property of Trabajo Social Global - Global Social Work and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The smart-grid approach undergoes many difficulties regarding the strategy that will enable its actual implementation. In this paper, an overview of real-time simulation technologies and their applicability to the smart-grid approach are presented as enabling steps toward the smart-grid's actual implementation. The objective of this work is to contribute with an introductory text for interested readers of real-time systems in the context of modern electric needs and trends. In addition, a comprehensive review of current applications of real-time simulation in electric systems is provided, together with the basis to understand real-time simulation and the topologies and hardware used to implement it. Furthermore, an overview of the evolution of real-time simulators in the industrial and academic background and its current challenges are introduced. [ABSTRACT FROM AUTHOR]

A general method for the straightforward synthesis of exocyclic allenes on five-, six-, seven-, and eight-membered oxygen heterocycles is described. A Barbier-type titanocene(III)-catalyzed cyclization of propargyl halides with a pendant carbonyl group is the key step of the process. This reaction is compatible with many functional groups, and can be smoothly carried out under neutral and mild conditions at room temperature. [ABSTRACT FROM AUTHOR]

Objectives: Simple nephrectomy is performed for a benign pathology that does not require the excision of either the adrenal gland or any adenopathies. When it is carried out in cases of stone disease, however, it is frequently not a "simple" technique owing to the presence of significant inflammation and infection. Methods: Ninety-six simple laparoscopic nephrectomies performed because of stone disease between 2006 and 2015 were retrospectively studied. A descriptive statistical analysis was performed, as well as an evaluation of the associated complications. Results: Of the 96 laparoscopic nephrectomies (62 left, 34 right), 7 (7.2%) had to be converted into open surgery owing to the impossibility of dissecting the renal hilum because of xanthogranulomatous pyelonephritis (n = 4) or major associated lesions (n = 3). The indication for nephrectomy was lumbar pain associated with urinary infection, with a partial renal function below 15% assessed by DMSA renal scan. There were three major complications. Pathologic assessment revealed chronic pyelonephritis with kidney atrophy and associated pyonephrosis in 85 cases, xanthogranulomatous pyelonephritis in 10, and pT4 squamous cell carcinoma in 1. Conclusions: Despite its high technical difficulty, simple laparoscopic nephrectomy for stones is a viable technique for advanced laparoscopists. Its principal advantage compared with open surgery is improved postsurgical recovery, and it is associated with an acceptable complication rate. Xanthogranulomatous pyelonephritis is not an initial contraindication to laparoscopy, but it is the most significant risk factor for conversion to open surgery. [ABSTRACT FROM AUTHOR]

Copyright of Gestión y Ambiente is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A synthesis of (±)-ambrox, a compound with delicious am bergris-type scent, is presented. The key step is a highly diastereoselective titanocene(III)-catalyzed radical tandem cyclization of a farneso derivative. [ABSTRACT FROM AUTHOR]

Basic human rights are not met in many parts of the world. Hunger, ill-health, and poor education are often part of the lives of the poor. The purpose of this study is to understand poor people's sources of strength, social relations, sources of income, and perspectives as strategies to cope with poverty in everyday life. Data gathering was done through field observations and semistructured interviews with poor and non-poor people in the Philippine town, Hagonoy. All data was codified according to recurrent and salient issues and analyzed using chiefly symbolic interactionism as the theoretical framework. The results of this study reveal that poor people suffer from stigmas. Poor people carry out various survival strategies: some strategies are creative, spiritual, and norm-breaking; social relations are important to cope with poverty. There are differences in the way poverty affects men and women due to culturally defined gender roles. The poor people in this study were marginalized into less desirable areas; because of their lack of resources they live in shanties where they have little protection. Calamities affect both the nonpoor and the poor people but the latter are in a less fortunate position. [ABSTRACT FROM AUTHOR]

The vast range of reactions mediated by titanocene monochloride (Cp2TiCl, the Nugent reagent) in organic synthetic chemistry is reviewed. The power of the Nugent reagent in organic chemistry is demonstrated by its ability to promote and/or catalyse several efficient transformations under mild reaction conditions in the presence of several functional groups, in an environmentally friendly manner and with use of simple experimental procedures. [ABSTRACT FROM AUTHOR]

Non‐ideal disturbance attenuation emerges in systems with sliding mode controllers when parasitic dynamics are present. In this work, the problem of non‐ideal disturbance attenuation in systems controlled by second‐order sliding modes is considered. Describing function and locus of a perturbed relay system (LPRS) methods are used for analysis of non‐ideal disturbance attenuation. The proposed solution is to introduce a linear compensator (series or parallel) in the control loop to modify the system frequency response, that is, the Nyquist plot or LPRS. The design methodology for both parallel and series compensators is presented. The proposed solution allows one to improve disturbance attenuation and tracking quality, thereby reducing the effect of parasitic dynamics which is reflected in the system frequency response. Experiments supporting the proposed approach and simulations are provided. [ABSTRACT FROM AUTHOR]

Copyright of Pasos: Revista de Turismo y Patrimonio Cultural is the property of Universidad de La Laguna, Instituto Universitario de Ciencias Politicas y Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Exocyclic allenes constitute useful building blocks in organic synthesis and have recently been identified as key intermediates in the synthesis of natural products. Here the first general method for the most straightforward synthesis of exocyclic allenes reported to date is presented. This method is based on the Barbier-type cyclization of propargyl halides catalyzed by titanium; a safe, abundant, and ecofriendly metal. The reaction proceeds under mild conditions compatible with different functional groups and provides good yields of five-, six-, and seven-membered carbocycles and nitrogen-containing heterocycles bearing an exocyclic allene group. Experimental evidence supporting the proposed reaction mechanism is also provided. Moreover, this procedure can be carried out in an enantioselective manner by using chiral titanocene(III) catalysts. The utility of this method has been proved in the synthesis of the natural alkaloid stemoamide. [ABSTRACT FROM AUTHOR]

The alkyne functional group is found in many bioactive natural products and is the key to many important chemical transformations developed over recent years. Moreover, allenes have recently gained relevance as versatile reagents in organic synthesis. Mild, catalytic methods to enable the selective introduction of either alkyne or allene motifs into organic molecules are very valuable but, as yet, quite scarce. We describe an extremely mild and selective method for either the propargylation or allenylation of carbonyl compounds catalyzed by the abundant, safe, and inexpensive metal titanium. These reactions can selectively provide homopropargylic alcohols from aldehydes and ketones or α-hydroxy-allenes from aldehydes. The mechanisms involved were also investigated. [ABSTRACT FROM AUTHOR]

Au/SiO and Ag/SiO supported metal-nanoparticles (MNPs) were implemented to fabricate SiO-based inorganic-inorganic hybrid sonogel films. Prepared Au/SiO- and Ag/SiO-MNPs exhibited low 2D-HCP crystallinity with particle diameters below 10 nm and homogeneous size distribution. The catalyst-free (CF) sonogel route was successfully implemented to produce these optically active nanocomposite films by doping the liquid sol-phase with these MNP systems and its subsequent deposition onto glass substrates via standard spin-coating procedures. The easy MNP-loading within the mesoporous dielectric sonogel network evidenced a huge chemical affinity between the silica sonogel hosting system and the guest SiO-supported MNPs. This fact allowed us to fabricate high quality hybrid films suitable for cubic nonlinear optical (NLO) characterizations via the Z-Scan technique. Indeed, the hosting sonogel network provided adequate thermal and mechanical stability protecting the active MNPs from environment conditions and diminished their tendency to aggregate; thus, preserving their pristine optical properties and morphology, giving rise to stable sol-gel hybrid films appropriate for photonic applications. Comprehensive morphological, structural, spectroscopic and nonlinear photophysical characterizations were optimally performed to the developed hybrid films. Our results have shown that the crystalline nature of the implemented MNPs, their small sizes and appropriate guest-host stabilizing interactions play a crucial role in the observation of improved cubic NLO-properties of these MNP structures embedded within the highly pure CF-sonogel confinement. [ABSTRACT FROM AUTHOR]

The frontal polymerization (FP) of bisphenol A ethoxylate diacrylate (BPAEDA) was carried with and without the presence of two different azobenzene comonomers by means of an external heating source. The first azomonomer (MDR-1) is a derivative of disperse red-1, N-ethyl- N-(2-hydroxyethyl)-4-(4-nitrophenylazo)aniline, whereas the second (E)-2-(4-((4-nitrophenyl)diazenyl)phenyl)-5,8,11-trioxa-2-azatridecan-13-yl methacrylate (4PEGMAN) comes from the azo-dye N-methyl- N-{4-[(E)-(4-nitrophenyl)diazenyl]phenyl}- N-(11-hydroxy-3,6,9-trioxaundecas-1-yl) amine. In this work, an ionic liquid trihexyltetradecylphosphonium persulfate was used as initiator. This compound produced stable propagating polymerization fronts with good velocities and moderate maximum temperature values. Moreover, this initiator prevented bubble formation and was found to be the most efficient when it was used in lower amounts with respect to other initiators, such as benzoyl peroxide, 2,2′-azobisisobutyronitrile, aliquat persulfate®, and tetrabutylphosphonium persulfate. The thermal properties of the obtained polymers and copolymers were determined by thermogravimetric analysis and differential scanning calorimetry. The nonlinear optical (NLO) characterizations of the developed BPAEDA/MDR-1 and BPAEDA/4PEGMAN copolymers were performed according to the Z-Scan technique in film samples prepared by classical polymerization. It has been proven that samples with higher 4PEGMAN content (0.26 mol %) exhibited outstanding cubic NLO-activity with positive NLO-refractive coefficients in the promising range of n2 = +3.2 × 10−4 esu. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

2-Phenoxyethyl acrylate (2-PEA) was polymerized alone and in the presence of an azobenzene comonomer derived from Disperse Red-1, N-ethyl- N-(2-hydroxyethyl)-4-(4-nitrophenylazo)aniline (MDR-1), by using the frontal polymerization technique. Two novel ionic liquids, recently synthesized by us, were used as initiators: tetrabutylphosphonium persulfate (TBPPS) and trihexyltetradecylphosphonium persulfate (TETDPPS). Even if their concentrations were smaller than those found when benzoyl peroxide and terbutylperoxy neodecanoate were used, these compounds gave rise to stable propagating polymerization fronts characterized by relatively low maximum temperatures and good velocities. Moreover, at variance to these latter, TBPPS and TETDPPS prevent bubble formation, thus allowing the use of the obtained materials in optical applications. The obtained polymers were characterized by infrared spectroscopy (FTIR), their thermal properties were determined by differential scanning calorimetry, and their optical properties were studied by absorption spectroscopy in the UV-vis region. Finally, the nonlinear optical (NLO) properties of the 2-PEA/MDR-1 copolymers obtained with TBPPS and TETDPPS were performed according to the Z-Scan technique with prepared film samples. It has been proven that samples with higher MDR-1 content (0.05 mol %) exhibited outstanding cubic NLO activity with negative NLO refractive coefficients around n2 = −1.7 × 10−3 esu. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Purpose: To study the utility of a training session offered to junior embryologists, comparing the results obtained with those reported by a group of senior embryologists. Methods: The 62 junior embryologists participanting were asked to decide on the quality of the embryos and theg clinical decision to be taken. Results: The junior embryologists' success rate following the training course was significantly higher than before for embryo classification (48.4% ± 20.4 vs. 59.7% ±16.7) ( p < 0.05) and for clinical decision (54.7% ± 19.6 vs. 68.7% ± 17.6) ( p < 0.005). Comparison of the degree of agreement between the categories assigned by the junior embryologists and those assigned by consensus among the group of senior embryologists revealed kappa values of k = 0.32 before the course and of k = 0.54 after it. The comparison between pre- and post-training junior and senior embryologists also reflected an improvement in the kappa index for clinical decision, from k = 0.54 to k = 0.68. Conclusions: Training courses are shown to be an effective tool for increasing the degree of agreement between junior and senior embryologists. [ABSTRACT FROM AUTHOR]

A novel polymer matrix containing amino-nitro substituted azobenzene groups was obtained by frontal polymerization. (E)-2-(Ethyl(4-((4-nitrophenyl)diazenyl)phenyl)amino)ethyl methacrylate (MDR-1) was copolymerized with poly(ethylene glycol) diacrylate (PEGDA) using this easy and fast polymerization technique. The effect of the amount of the incorporated azo-monomer into the polymer matrix was studied in detail and correlated to front velocity, maximum temperature, initiator concentration, and monomer conversion. The obtained materials were characterized by infrared spectroscopy (Fourier transform infrared), and their thermal properties were studied by thermogravimetric analysis and differential scanning calorimetry. Moreover, the optical properties of the polymers were studied by absorption spectroscopy in the UV-Vis region. Absorption spectra of the copolymers exhibit a significant blue shift of the absorption bands with respect to the azo-monomer, due to the presence of H-aggregates. Cubic nonlinear optical (NLO) characterizations of the PEGDA/MDR-1 copolymers were performed according to the Z-Scan technique. It has been proven that samples with higher MDR-1 content (0.75 mol %) exhibited outstandingly high NLO-activity with negative NLO-refractive coefficients in the promising range of n2 = −8.057 × 10−4 esu. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

Patients undergoing hemodialysis have a lower survival rate than those who receive a kidney transplant. Mortality among hemodialysis patients is approximately 14.5% compared with 1.5% for transplant recipients. One of the exclusion criteria for renal transplant is severe iliac artery calcification. We performed an aortofemoral bypass in these patients to make them eligible for renal transplantation. Eleven patients were selected to receive an aortofemoral bypass. All had severe calcification of iliac arteries. Eight patients required a bypass from the thoracic aorta and two from the infrarenal level. Revascularization was successful in 10 patients. Patency was 100%. Surgery could not be performed in one owing to severe calcification of the femoral artery. One patient died owing to gastrointestinal bleeding. Two patients developed complications; one needed a splenectomy, and the other developed meningitis and paralytic ileus. To date, four patients have received transplants, and the viability of the transplanted kidney is good in all cases. Renal transplantation is the only method known to improve survival and quality of life for hemodialysis patients. We consider that if patients with severe iliac calcification are well informed of the morbidity and mortality risk of an aortic bypass, this intervention can be justified in this setting. [ABSTRACT FROM AUTHOR]

Wünderlich's syndrome is a spontaneous nontraumatic massive retroperitoneal hemorrhage. It is usually secondary to a renal neoplasm, with angiomyolipoma being the most frequent followed by renal cell carcinoma. The management of spontaneous retroperitoneal bleeding varies depending on the hemodynamic status of the patient. We present the first report of a transperitoneal laparoscopic nephrectomy in a patient with spontaneous retroperitoneal active bleeding secondary to a right renal mass. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]