Transitioning from Methanol to Olefins (MTO) toward a Tandem CO2 Hydrogenation Process: On the Role and Fate of Heteroatoms (Mg, Si) in MAPO-18 Zeotypes.

The tandem CO2 hydrogenation to hydrocarbons over mixed metal oxide/zeolite catalysts (OXZEO) is an efficient way of producing value-added hydrocarbons (platform chemicals and fuels) directly from CO2via methanol intermediate in a single reactor. In this contribution, two MAPO-18 zeotypes (M = Mg, Si) were tested and their performance was compared under methanol-to-olefins (MTO) conditions (350 °C, PCH3OH = 0.04 bar, 6.5 gCH3OH h-1 g-1), methanol/CO/H2 cofeed conditions (350 °C, PCH3OH/PCO/PH2 = 1:7.3:21.7 bar, 2.5 gCH3OH h-1 g-1), and tandem CO2 hydrogenation-to-olefin conditions (350 °C, PCO2/PH2 = 7.5:22.5 bar, 1.4-12.0 gMAPO-18 h molCO2-1). In the latter case, the zeotypes were mixed with a fixed amount of ZnO:ZrO2 catalyst, well-known for the conversion of CO2/H2 to methanol. Focus was set on the methanol conversion activity, product selectivity, and performance stability with time-on-stream. In situ and ex situ Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), solid-state nuclear magnetic resonance (NMR), sorption experiments, and ab initio molecular dynamics (AIMD) calculations were performed to correlate material performance with material characteristics. The catalytic tests demonstrated the better performance of MgAPO-18 versus SAPO-18 at MTO conditions, the much superior performance of MgAPO-18 under methanol/CO/H2 cofeeds, and yet the increasingly similar performance of the two materials under tandem conditions upon increasing the zeotype-to-oxide ratio in the tandem catalyst bed. In situ FT-IR measurements coupled with AIMD calculations revealed differences in the MTO initiation mechanism between the two materials. SAPO-18 promoted initial CO2 formation, indicative of a formaldehyde-based decarboxylation mechanism, while CO and ketene were the main constituents of the initiation pool in MgAPO-18, suggesting a decarbonylation mechanism. Under tandem CO2 hydrogenation conditions, the presence of high water concentrations and low methanol partial pressure in the reaction medium led to lower, and increasingly similar, methanol turnover frequencies for the zeotypes. Despite both MAPO-18 zeotypes showing signs of activity loss upon storage due to the interaction of the sites with ambient humidity, they presented a remarkable stability after reaching steady state under tandem reaction conditions and after steaming and regeneration cycles at high temperatures. Water adsorption experiments at room temperature confirmed this observation. The faster activity loss observed in the Mg version is assigned to its harder Mg2+-ion character and the higher concentration of CHA defects in the AEI structure, identified by solid-state NMR and XRD. The low stability of a MgAPO-34 zeotype (CHA structure) upon storage corroborated the relationship between CHA defects and instability.

Social movements in the context of crisis: waste picker organizations as collaborative public partners in the context of the COVID-19 pandemic.

Social movements are purposeful, organized groups of people addressing the creation and reproduction of inequality, rights and access issues, seeking to transform sectoral policies. In the context of the COVID-19 pandemic, social movements have been acting in articulation with government and private companies and through other actions formulated within their networks, as service deliverers to the poor and vulnerable populations most heavily affected, often filling a gap created by unfulfilled policies. Our research with waste picker organizations in Brazil illustrates how their struggle for recognition has taken action in this context. Academic and government documents, social media and online material (blogs, posts, websites, etc.) and virtual meetings inform this research. We found that multiple actors have contributed to mitigate the urgent needs of waste pickers during the pandemic, but that at the same time, pre-existing challenges in waste management and the lack of wide-ranging social and economic inclusion have been further intensified.

[Effectiveness of treatment with Pygeum africanum in patients with lower urinary tract symptoms and benign prostatic hyperplasia: a cross-sectional study in the real-world clinical practice in Spain (The PROFIT Study)]. / Efectividad del tratamiento con Pygeum africanum en pacientes con síntomas del tracto urinario inferior e hiperplasia benigna de próstata: estudio transversal en la práctica clínica real en España (Estudio PROFIT).

OBJECTIVES: To assess the effectivenessand tolerability of treatment with P africanum(P. africanum) in patients with lower urinary tractsymptoms (LUTS) associated with benign prostatichyperplasia (BPH) in routine clinical practice. MATERIAL AND METHODS: Cross-sectional observationalstudy in which 115 patients with LUTS/BPHtreated for 6 months with P. africanum (Tebetane® compuesto)in real-world clinical practice conditions wereincluded. The primary objective was to assess thequality of life (QoL) according to changes in the scoresof item 8 of the International Prostate Symptom Score(IPSS) questionnaire (a score ≥ 4 indicates a significantimpairment of QoL). Secondary objectives includedimprovement of urinary symptoms, urinary flow, satisfactionand compliance with treatment as well astolerability. Data were collected in a single scheduledvisit at 6 months of treatment with P. africanum andwere compared with data registered in the medicalrecords at the beginning of treatment. RESULTS: After 6 months of treatment withP. africanum, the percentage of patient with significantimpairment of QoL was 22.6% as compared with45.2% at the initiation of treatment (P 0,-001). Theoverall IPSS score showed a mean decreas of -4,-5points (median -4,0, interquartile range [IQR] -7,-0 to-2,0) and 69 patients (60%) showed a clinically significantimprovement (reduction of ≥ 4 points). Therewere significant decreases in IPSS subscales of storage(mean -1,-8; median -2,-0, IQR -3,-0 to 0 (P 0,-001)and voiding (mean -1,-9; median -2,-0, IQR -3,-0 to 0)(P 0,-001) symptoms. The degree of satisfaction and compliance with treatment was high with mean scores(median) of 6,9 (7,0) and 9,2 (10), respectively in the1-10 visual analogue scale. Treatment-related adverseeffects did not occur. CONCLUSIONS: Treatment with P. africanum during6 months improved significantly QoL and LUTS inpatients with BPH, with a high level of satisfaction andcompliance with treatment, without adverse events.

OBJETIVO: Evaluar la efectividad y latolerabilidad del tratamiento con Pygeum africanum (P.africanum) en pacientes con síntomas del tracto urinarioinferior (STUI) asociados a hiperplasia benigna depróstata (HBP) en la práctica clínica habitual.MATERIAL Y MÉTODOS: Estudio observacionaltransversal en el que se incluyeron 115 pacientes conSTUI/HBP tratados durante 6 meses con P. africanum (Tebetane® compuesto) en condiciones de prácticaclínica real. El objetivo primario fue evaluar la calidadde vida (CdV) en función del cambio en la pregunta 8del cuestionario de Puntuación Internacional de losSíntomas Prostáticos (IPSS) (puntuación ≥ 4 indicaafectación significativa de la CdV). Los objetivos secundariosincluyeron la mejoría de síntomas urinarios,flujo urinario, satisfacción y cumplimiento con eltratamiento, así como la tolerabilidad del mismo. Losdatos se recogieron en una única visita programada alos 6 meses de tratamiento con P. africanum y se compararoncon los registrados en la historia clínica alinicio del tratamiento. RESULTADOS: Tras 6 meses de tratamiento conP. africanum, el porcentaje de pacientes con afectaciónsignificativa de la CdV fue del 22,6% en comparacióncon un 45,2% al inicio del tratamiento (P 0,001).La puntuación global del IPSS disminuyó de mediaen -4,5 puntos (mediana -4,0, rango intercuartílico [RIQ] -7,0 a -2,0) y 69 pacientes (60%) mostraron unamejoría clínicamente significativa (disminución ≥ 4puntos). Se observaron disminuciones significativasen las subescalas del IPSS de los síntomas de llenado(media -1,8; mediana -2,0, RIQ -3,0 a 0) (P 0,001) yvaciado (media -1,9; mediana -2,0, RIQ -3,0 a 0) (P 0,001). El grado de satisfacción y cumplimiento con eltratamiento fue elevado con valores medios (mediana)de 6,9 (7,0) y 9,2 (10) respectivamente, en una escalaanalógica visual 1-10 cm. No se registraron efectosadversos relacionados con el tratamiento. CONCLUSION: El tratamiento con P. africanum(P. africanum) durante 6 meses mejoró significativamentela CdV y los STUI en pacientes con HBP, con unalto grado de satisfacción y cumplimiento con el tratamiento,sin registrarse reacciones adversas.

Efectividad del tratamiento con pygeum africanum en pacientes con síntomas del tracto urinario inferior e hiperplasia benigna de próstata: estudio transversal en la práctica clínica real en españa (estudio profit) / Effectiveness of treatment with Pygeum africanum in patients with lower urinary tract symptoms and benign prostatic hyperplasia: a cross-sectional study in the real-world clinical practice in Spain (The PROFIT Study)

OBJETIVO: Evaluar la efectividad y latolerabilidad del tratamiento con Pygeum africanum (P.africanum) en pacientes con síntomas del tracto urinario inferior (STUI) asociados a hiperplasia benigna depróstata (HBP) en la práctica clínica habitual.MATERIAL Y MÉTODOS: Estudio observacionaltransversal en el que se incluyeron 115 pacientes conSTUI/HBP tratados durante 6 meses con P. africanum (Tebetane® compuesto) en condiciones de prácticaclínica real. El objetivo primario fue evaluar la calidadde vida (CdV) en función del cambio en la pregunta 8del cuestionario de Puntuación Internacional de losSíntomas Prostáticos (IPSS) (puntuación ≥ 4 indicaafectación significativa de la CdV). Los objetivos secundarios incluyeron la mejoría de síntomas urinarios, flujo urinario, satisfacción y cumplimiento con eltratamiento, así como la tolerabilidad del mismo. Losdatos se recogieron en una única visita programada alos 6 meses de tratamiento con P. africanum y se compararon con los registrados en la historia clínica alinicio del tratamiento.RESULTADOS: Tras 6 meses de tratamiento conP. africanum, el porcentaje de pacientes con afectaciónsignificativa de la CdV fue del 22,6% en comparacióncon un 45,2% al inicio del tratamiento (P < 0,001).La puntuación global del IPSS disminuyó de mediaen -4,5 puntos (mediana -4,0, rango intercuartílico [RIQ] -7,0 a -2,0) y 69 pacientes (60%) mostraron unamejoría clínicamente significativa (disminución ≥ 4puntos). Se observaron disminuciones significativasen las subescalas del IPSS de los síntomas de llenado(media -1,8; mediana -2,0, RIQ -3,0 a 0) (P < 0,001) yvaciado (media -1,9; mediana -2,0, RIQ -3,0 a 0) (P <0,001). El grado de satisfacción y cumplimiento con eltratamiento fue elevado con valores medios (mediana)de 6,9 (7,0) y 9,2 (10) respectivamente, en una escalaanalógica visual 1-10 cm. No se registraron efectosadversos relacionados con el tratamiento.

OBJECTIVES: To assess the effectiveness and tolerability of treatment with P africanum(P. africanum) in patients with lower urinary tractsymptoms (LUTS) associated with benign prostatichyperplasia (BPH) in routine clinical practice.MATERIAL AND METHODS: Cross-sectional observational study in which 115 patients with LUTS/BPHtreated for 6 months with P. africanum (Tebetane® compuesto) in real-world clinical practice conditions wereincluded. The primary objective was to assess thequality of life (QoL) according to changes in the scoresof item 8 of the International Prostate Symptom Score(IPSS) questionnaire (a score ≥ 4 indicates a significantimpairment of QoL). Secondary objectives includedimprovement of urinary symptoms, urinary flow, satisfaction and compliance with treatment as well astolerability. Data were collected in a single scheduledvisit at 6 months of treatment with P. africanum andwere compared with data registered in the medicalrecords at the beginning of treatment.RESULTS: After 6 months of treatment withP. africanum, the percentage of patient with significant impairment of QoL was 22.6% as compared with45.2% at the initiation of treatment (P < 0,-001). Theoverall IPSS score showed a mean decreas of -4,-5points (median -4,0, interquartile range [IQR] -7,-0 to-2,0) and 69 patients (60%) showed a clinically significant improvement (reduction of ≥ 4 points). Therewere significant decreases in IPSS subscales of storage(mean -1,-8; median -2,-0, IQR -3,-0 to 0 (P < 0,-001)and voiding (mean -1,-9; median -2,-0, IQR -3,-0 to 0)(P < 0,-001) symptoms. The degree of satisfaction and compliance with treatment was high with mean scores(median) of 6,9 (7,0) and 9,2 (10), respectively in the1-10 visual analogue scale. Treatment-related adverseeffects did not occur.CONCLUSIONS: Treatment with P. africanum during 6 months improved significantly QoL and LUTS inpatients with BPH, with a high level of satisfaction

An identification case study from fingerprint photographs.

This study is a fingerprint comparison of the friction skin detail observed on fingers appearing in ten photographs requested by the Historic Heritage Brigade. These photographs had been uploaded to an online marketplace and show a hand holding different archaeological pieces that had allegedly been stolen. After the ten images had been digitally optimized, seven were determined to contain sufficient clear and continuous ridge detail for the purpose of fingerprint comparison and search. These imprints were compared to the fingerprints of the subject under investigation. Four of them were matched to the index finger, two with the middle finger and one with the ring finger, all from the left hand. These fingerprints were also entered into the Spanish Automated Fingerprint Identification System, resulting in a match to the individual under investigation by the Judicial Police Group.

Special Issue on GNSS Data Processing and Navigation.

Global Navigation Satellite System (GNSS) data can be used in a myriad of ways. The current number of applications exceed by far those originally GNSS was designed for. As an example, the present Special Issue on GNSS Data Processing and Navigation compiles 14 international contributions covering several aspects of GNSS research. This Editorial summarizes the whole special issue grouping the contributions under four different, but related topics.

Empirical Mode Decomposition-Based Filter Applied to Multifocal Electroretinograms in Multiple Sclerosis Diagnosis.

As multiple sclerosis (MS) usually affects the visual pathway, visual electrophysiological tests can be used to diagnose it. The objective of this paper is to research methods for processing multifocal electroretinogram (mfERG) recordings to improve the capacity to diagnose MS. MfERG recordings from 15 early-stage MS patients without a history of optic neuritis and from 6 control subjects were examined. A normative database was built from the control subject signals. The mfERG recordings were filtered using empirical mode decomposition (EMD). The correlation with the signals in a normative database was used as the classification feature. Using EMD-based filtering and performance correlation, the mean area under the curve (AUC) value was 0.90. The greatest discriminant capacity was obtained in ring 4 and in the inferior nasal quadrant (AUC values of 0.96 and 0.94, respectively). Our results suggest that the combination of filtering mfERG recordings using EMD and calculating the correlation with a normative database would make mfERG waveform analysis applicable to assessment of multiple sclerosis in early-stage patients.

Computer-Aided Diagnosis of Multiple Sclerosis Using a Support Vector Machine and Optical Coherence Tomography Features.

The purpose of this paper is to evaluate the feasibility of diagnosing multiple sclerosis (MS) using optical coherence tomography (OCT) data and a support vector machine (SVM) as an automatic classifier. Forty-eight MS patients without symptoms of optic neuritis and forty-eight healthy control subjects were selected. Swept-source optical coherence tomography (SS-OCT) was performed using a DRI (deep-range imaging) Triton OCT device (Topcon Corp., Tokyo, Japan). Mean values (right and left eye) for macular thickness (retinal and choroidal layers) and peripapillary area (retinal nerve fibre layer, retinal, ganglion cell layer-GCL, and choroidal layers) were compared between both groups. Based on the analysis of the area under the receiver operator characteristic curve (AUC), the 3 variables with the greatest discriminant capacity were selected to form the feature vector. A SVM was used as an automatic classifier, obtaining the confusion matrix using leave-one-out cross-validation. Classification performance was assessed with Matthew's correlation coefficient (MCC) and the AUCCLASSIFIER. The most discriminant variables were found to be the total GCL++ thickness (between inner limiting membrane to inner nuclear layer boundaries), evaluated in the peripapillary area and macular retina thickness in the nasal quadrant of the outer and inner rings. Using the SVM classifier, we obtained the following values: MCC = 0.81, sensitivity = 0.89, specificity = 0.92, accuracy = 0.91, and AUCCLASSIFIER = 0.97. Our findings suggest that it is possible to classify control subjects and MS patients without previous optic neuritis by applying machine-learning techniques to study the structural neurodegeneration in the retina.

Effect of intraoperative paravertebral or intravenous lidocaine versus control during lung resection surgery on postoperative complications: A randomized controlled trial.

BACKGROUND: Use of minimally invasive surgical techniques for lung resection surgery (LRS), such as video-assisted thoracoscopy (VATS), has increased in recent years. However, there is little information about the best anesthetic technique in this context. This surgical approach is associated with a lower intensity of postoperative pain, and its use has been proposed in programs for enhanced recovery after surgery (ERAS). This study compares the severity of postoperative complications in patients undergoing LRS who have received lidocaine intraoperatively either intravenously or via paravertebral administration versus saline. METHODS/DESIGN: We will conduct a single-center randomized controlled trial involving 153 patients undergoing LRS through a thoracoscopic approach. The patients will be randomly assigned to one of the following study groups: intravenous lidocaine with more paravertebral thoracic (PVT) saline, PVT lidocaine with more intravenous saline, or intravenous remifentanil with more PVT saline. The primary outcome will be the comparison of the postoperative course through Clavien-Dindo classification. Furthermore, we will compare the perioperative pulmonary and systemic inflammatory response by monitoring biomarkers in the bronchoalveolar lavage fluid and blood, as well as postoperative analgesic consumption between the three groups of patients. We will use an ANOVA to compare quantitative variables and a chi-squared test to compare qualitative variables. DISCUSSION: The development of less invasive surgical techniques means that anesthesiologists must adapt their perioperative management protocols and look for anesthetic techniques that provide good analgesic quality and allow rapid rehabilitation of the patient, as proposed in the ERAS protocols. The administration of a continuous infusion of intravenous lidocaine has proven to be useful and safe for the management of other types of surgery, as demonstrated in colorectal cancer. We want to know whether the continuous administration of lidocaine by a paravertebral route can be substituted with the intravenous administration of this local anesthetic in a safe and effective way while avoiding the risks inherent in the use of regional anesthetic techniques. In this way, this technique could be used in a safe and effective way in ERAS programs for pulmonary resection. TRIAL REGISTRATION: EudraCT, 2016-004271-52; ClinicalTrials.gov, NCT03905837 . Protocol number IGGFGG-2016 version 4.0, 27th April 2017.

Uso del valor de la hormona paratiroidea intacta en el primer día postoperatorio tras tiroidectomía total como predictor de hipoparatiroidismo permanente / Serum levels of intact parathyroid hormone on the first day after total thyroidectomy as predictor of permanent hypoparathyroidism

Introducción: El hipoparatiroidismo permanente es la complicación a largo plazo más prevalente tras una tiroidectomía total, siendo responsable de una importante morbilidad y de necesidad de tratamiento sustitutivo a largo plazo. El objetivo de este estudio fue determinar si el valor de la hormona paratiroidea intacta (PTHi) en el primer día postoperatorio tras una tiroidectomía total es un buen predictor de hipoparatiroidismo permanente. Material y métodos: Estudio retrospectivo de observación en el que se analizaron todos los pacientes intervenidos de tiroidectomía total entre enero de 2009 y diciembre de 2014. Se recogieron los valores de PTHi y calcio sérico en el primer día postoperatorio, y todos los pacientes tuvieron un seguimiento mínimo de un año. Resultados: Se incluyeron 481 pacientes con una edad media de 53±14 años, el 82% de los cuales eran mujeres. La causa más frecuente de tiroidectomía fue el bocio multinodular (75%), seguido del carcinoma papilar de tiroides (15%). La complicación precoz más frecuente fue la hipocalcemia transitoria (49%), y a largo plazo fue el hipoparatiroidismo permanente (6%). El estudio estadístico mediante curvas ROC mostró que la PTHi en el primer día postoperatorio es un buen predictor de hipoparatiroidismo permanente (área bajo la curva de 0,87; IC 95%: 0,84-0,91). Valores de 5pg/ml presentan una sensibilidad del 95%, una especificidad del 77%, un valor predictivo positivo del 21,6% y un valor predictivo negativo del 99,6%. Conclusiones: La PTHi en el primer día postoperatorio de la tiroidectomía total es un predictor útil de hipoparatiroidismo permanente gracias a su alto valor predictivo negativo. Valores de PTHi>5 pg/ml excluyen prácticamente la presencia de hipoparatiroidismo permanente

Background: Permanent hypoparathyroidism is the most common long-term complication after total thyroidectomy, causing significant morbidity and requiring long-term replacement therapy. Our study objective was to assess whether intact parathyroid hormone (iPTH) levels on the first day after total thyroidectomy are a good predictor of permanent hypoparathyroidism. Patients and methods: A retrospective observational study of all patients undergoing total thyroidectomy between January 2009 and December 2014. iPTH and calcium levels were measured the first day after surgery. Patients were followed up for at least one year after surgery. Results: The study group consisted of 481 patients with a mean age of 53±14 years, 82% of them females. The most common reason for thyroidectomy was multinodular goiter (75%), followed by papillary thyroid cancer (15%). Transient hypocalcemia was the most common early complication after total thyroidectomy (49%), and permanent hypoparathyroidism was the most common long-term complication (6%). ROC curve analysis showed that iPTH level on the first postoperative day was a good predictor of permanent hypoparathyroidism (area under the curve 0.87; 95% CI: 0.84-0.91). Cut-off iPTH levels of 5pg/mL had 95% sensitivity, 77% specificity, 21.6% positive predictive value, and 99.6% negative predictive value. Conclusions: iPTH level on the first day after total thyroidectomy is a useful predictor of permanent hypoparathyroidism because of its high negative predictive value. Serum iPTH levels >5pg/mL virtually exclude presence of permanent hypoparathyroidism

Serum levels of intact parathyroid hormone on the first day after total thyroidectomy as predictor of permanent hypoparathyroidism. / Uso del valor de la hormona paratiroidea intacta en el primer día postoperatorio tras tiroidectomía total como predictor de hipoparatiroidismo permanente.

BACKGROUND: Permanent hypoparathyroidism is the most common long-term complication after total thyroidectomy, causing significant morbidity and requiring long-term replacement therapy. Our study objective was to assess whether intact parathyroid hormone (iPTH) levels on the first day after total thyroidectomy are a good predictor of permanent hypoparathyroidism. PATIENTS AND METHODS: A retrospective observational study of all patients undergoing total thyroidectomy between January 2009 and December 2014. iPTH and calcium levels were measured the first day after surgery. Patients were followed up for at least one year after surgery. RESULTS: The study group consisted of 481 patients with a mean age of 53±14 years, 82% of them females. The most common reason for thyroidectomy was multinodular goiter (75%), followed by papillary thyroid cancer (15%). Transient hypocalcemia was the most common early complication after total thyroidectomy (49%), and permanent hypoparathyroidism was the most common long-term complication (6%). ROC curve analysis showed that iPTH level on the first postoperative day was a good predictor of permanent hypoparathyroidism (area under the curve 0.87; 95% CI: 0.84-0.91). Cut-off iPTH levels of 5pg/mL had 95% sensitivity, 77% specificity, 21.6% positive predictive value, and 99.6% negative predictive value. CONCLUSIONS: iPTH level on the first day after total thyroidectomy is a useful predictor of permanent hypoparathyroidism because of its high negative predictive value. Serum iPTH levels >5pg/mL virtually exclude presence of permanent hypoparathyroidism.

Abandoned Object Detection in Video-Surveillance: Survey and Comparison.

During the last few years, abandoned object detection has emerged as a hot topic in the video-surveillance community. As a consequence, a myriad of systems has been proposed for automatic monitoring of public and private places, while addressing several challenges affecting detection performance. Due to the complexity of these systems, researchers often address independently the different analysis stages such as foreground segmentation, stationary object detection, and abandonment validation. Despite the improvements achieved for each stage, the advances are rarely applied to the full pipeline, and therefore, the impact of each stage of improvement on the overall system performance has not been studied. In this paper, we formalize the framework employed by systems for abandoned object detection and provide an extensive review of state-of-the-art approaches for each stage. We also build a multi-configuration system allowing one to select a range of alternatives for each stage with the objective of determining the combination achieving the best performance. This multi-configuration is made available online to the research community. We perform an extensive evaluation by gathering a heterogeneous dataset from existing data. Such a dataset allows considering multiple and different scenarios, whereas presenting various challenges such as illumination changes, shadows, and a high density of moving objects, unlike existing literature focusing on a few sequences. The experimental results identify the most effective configurations and highlight design choices favoring robustness to errors. Moreover, we validated such an optimal configuration on additional datasets not previously considered. We conclude the paper by discussing open research challenges arising from the experimental comparison.

Enantiosensitive Bonding of Chiral Molecules on a Magnetic Substrate Investigated by Means of Electron Spectroscopies.

The adsorption of purely organic chiral molecules on ferromagnetic Co thin films is studied under ultra high vacuum conditions by means of synchrotron radiation-based electron spectroscopies, namely X-ray absorption and ultraviolet photoemission. X-ray absorption reveals that enantiomers with opposite handedness (R,R)- and (S,S)- of two different molecules adsorb with different strength on the Co surfaces and their valence band photoemission spectra also display distinctive features. In view of the recent reports describing the chiral-induced spin selectivity (CISS) effect these results lead us to consider the possibility that some enantiosensitivity may appear when bonding chiral molecules to a substrate with an initial asymmetry in the population of the different spin orientations.

Empirical mode decomposition processing to improve multifocal-visual-evoked-potential signal analysis in multiple sclerosis.

OBJECTIVE: To study the performance of multifocal-visual-evoked-potential (mfVEP) signals filtered using empirical mode decomposition (EMD) in discriminating, based on amplitude, between control and multiple sclerosis (MS) patient groups, and to reduce variability in interocular latency in control subjects. METHODS: MfVEP signals were obtained from controls, clinically definitive MS and MS-risk progression patients (radiologically isolated syndrome (RIS) and clinically isolated syndrome (CIS)). The conventional method of processing mfVEPs consists of using a 1-35 Hz bandpass frequency filter (XDFT). The EMD algorithm was used to decompose the XDFT signals into several intrinsic mode functions (IMFs). This signal processing was assessed by computing the amplitudes and latencies of the XDFT and IMF signals (XEMD). The amplitudes from the full visual field and from ring 5 (9.8-15° eccentricity) were studied. The discrimination index was calculated between controls and patients. Interocular latency values were computed from the XDFT and XEMD signals in a control database to study variability. RESULTS: Using the amplitude of the mfVEP signals filtered with EMD (XEMD) obtains higher discrimination index values than the conventional method when control, MS-risk progression (RIS and CIS) and MS subjects are studied. The lowest variability in interocular latency computations from the control patient database was obtained by comparing the XEMD signals with the XDFT signals. Even better results (amplitude discrimination and latency variability) were obtained in ring 5 (9.8-15° eccentricity of the visual field). CONCLUSIONS: Filtering mfVEP signals using the EMD algorithm will result in better identification of subjects at risk of developing MS and better accuracy in latency studies. This could be applied to assess visual cortex activity in MS diagnosis and evolution studies.

Modeling the Effect of Optical Signal Multipath.

Here, we propose a model to determine the effect of multipath in indoor environments when the shape and characteristics of the environment are known. The main paper goal is to model the multipath signal formation to solve, as much as possible, the negative effects in light communications, as well as the indoor positioning errors due to this phenomenon when using optical signals. The methodology followed was: analyze the multipath phenomenon, establish a theoretical approach and propose different models to characterize the behavior of the channel, emitter and receiver. The channel impulse response and received signal strength are obtained from different proposed algorithms. We also propose steps for implementing a numerical procedure to calculate the effects of these multipaths using information that characterizes the environment, transmitter and receiver and their corresponding positions. In addition, the results of an empirical test in a controlled environment are compared with those obtained using the model, in order to validate the latter. The results may largely vary with respect to the cell size used to discretize the environment. We have concluded that a cell size whose side is 20-times smaller than the minimum distance between emitter and receiver (i.e., 10 cm × 10 cm for a 2-m distance) provides almost identical results between the empirical tests and the proposed model, with an affordable computational load.

Indoor Positioning System Based on a PSD Detector, Precise Positioning of Agents in Motion Using AoA Techniques.

Here, we present an indoor positioning system (IPS) for detecting mobile agents based on a single Position Sensitive Device sensor (PSD) sited in the environment and InfraRed Emitter Diode (IRED) located on mobile agents. The main goal of the work is to develop an alternative IPS to other sensing technologies, cheaper, easier to install and with a low computational load to obtain a high rate of measurements per second. The proposed IPS has the capacity to accurately determine 3D position from the angle of arrival (AoA) of the signal received at the PSD sensor. In this first approach to the method, the agents are considered to move along a plane. We propose two alternatives for determining position: in one, tones are emitted on a frequency unique to each transmitter, while in the other, sequences are emitted.The paper proposes and set up a very simple and easy to deploy system capable of performing 3D positioning with a single analog sensor, obtaining a high accurate positioning and a reduced execution time for the signal processing. The low computational load of the IPS makes it possible to obtain a very high position update rate (more than 100 times per second), yielding millimetric accuracies.

Modeling Infrared Signal Reflections to Characterize Indoor Multipath Propagation.

In this paper, we propose a model to characterize Infrared (IR) signal reflections on any kind of surface material, together with a simplified procedure to compute the model parameters. The model works within the framework of Local Positioning Systems (LPS) based on IR signals (IR-LPS) to evaluate the behavior of transmitted signal Multipaths (MP), which are the main cause of error in IR-LPS, and makes several contributions to mitigation methods. Current methods are based on physics, optics, geometry and empirical methods, but these do not meet our requirements because of the need to apply several different restrictions and employ complex tools. We propose a simplified model based on only two reflection components, together with a method for determining the model parameters based on 12 empirical measurements that are easily performed in the real environment where the IR-LPS is being applied. Our experimental results show that the model provides a comprehensive solution to the real behavior of IR MP, yielding small errors when comparing real and modeled data (the mean error ranges from 1% to 4% depending on the environment surface materials). Other state-of-the-art methods yielded mean errors ranging from 15% to 40% in test measurements.

Effect of drug interactions involving antiretroviral drugs on viral load in HIV population.

BACKGROUND: Most studies focus on potential drug interactions, without considering the effect of these on the response to antiretroviral (ARV) therapy. We assess the effect of potential drug-drug interactions (pDDIs) that could have lowered the ARV concentration (pDDI-lowerARV) on HIV viral load. METHODS: Retrospective observational cohort study was conducted on all HIV-infected outpatients attending the Pharmacy Service of a regional reference hospital in Murcia (south-eastern Spain). The complete treatment was subsequently screened for pDDIs using the database 'InteraccionesHIV.com'. The study focused on interactions involving at least one ARV drug and, especially, any pDDI-lowerARV. RESULTS: Two hundred and twenty-nine patients were included in the study. A total of 168 pDDIs were identified, of which 62 (36.9%) had the potential to lower ARV concentrations. In 77% of cases, the drug involved in the reduction of plasma concentrations was a protease inhibitor (PI), and in the rest of the drug interactions the ARV drug affected was a non-nucleoside reverse-transcriptase inhibitor. Baseline viral suppression was noted in 57.1% of patients with pDDI-lowerARV compared with 61.5% of patients without pDDI-lowerARV (p=0.605), and in 85.7% versus 79.7%, respectively, after a 24-week follow-up period (p=0.516). CONCLUSIONS: This study shows that prevalence of pDDI-lowerARV was high; however, no association was found between the presence of these interactions and virological failure. These results confirm the need for further studies to understand the consequences of interactions in real-life clinical practice, since most pharmacokinetic studies tend to evaluate the ability of interaction between two drugs under controlled conditions.

Enantiospecific spin polarization of electrons photoemitted through layers of homochiral organic molecules.

Electrons photoemitted through layers of purely organic chiral molecules become strongly spin-polarized even at room temperature and for double-monolayer thicknesses. The substitution of one enantiomer for its mirror image does not revert the sign of the spin polarization, rather its direction in space. These findings might lead to the obtention of highly efficient spin filters for spintronic applications.

Driving position field study, differences with the whiplash protocol and biomechanics experimental responses.

Rear-impact collisions at low speed are a leading cause of economic costs among motor vehicle accidents. Recently, EuroNCAP has incorporated in its protocol the whiplash test, to reproduce a low-speed rear impact. This paper presents a field driving study to assess the potential differences between the EuroNCAP dummy tests and actual drivers in the field, focusing on occupant position and biomechanics experimental results. A total of 182 drivers were randomly selected in two geographical areas in Spain. The driving position of each driver was recorded with a focus on the most relevant measurements for rear impact. Statistical analysis was performed to obtain means, standard deviations and density functions to compare observational seating position with that of the EuroNCAP testing protocol. The observational data showed a similar seatback angle to that used in the EuroNCAP protocol (24° in front of 25° for the protocol), a greater distance between the head vertex and the top of the head restraint (53mm compared to 39.5mm), and less distance between the occipital bone of the head and the headrest (67.9 compared to 89.3mm). Based on these data, 4 dummy tests were conducted using the dummy BioRID IIg. The baseline test was designed to reproduce the dummy position according to EuroNCAP 3.0 whiplash protocol. Three different additional tests were defined to reproduce the actual observed driving position as well as to assess a "worst case" scenario in terms of reduced seatback angle. These variations in initial driver position, comparing the EuroNCAP protocol to the observational study results, were not observed to cause significant differences in the biomechanical values measured in the BioRID IIg, The T1 acceleration was reduced less than 8%, the NIC was increased about 8%, and the NKm presented a reduction of 20%. Reducing the seat angle was observed to be more harmful in terms of NIC.