bluuebunny/crossref_metadata_2025 huggingface dataset:
Acute Stroke Mimics: Etiological Spectrum and Efficacy of FAST, BE FAST, and the ROSIER Scores
Authors: Aaron Sanjith , A. T. Prabhakar , Mathew Vivek , Jeyaseelan Lakshmanan , Benjamin Kenneth , Abhilash K. P. P. , Ahmed Shaikh Atif Iqbal , Nair Aditya V.
Published: December 2020

Background and Purpose:

Stroke mimics constitute a good number of patients referred as acute strokes within the window period for acute therapies. Proper triaging can avoid unnecessary imaging and even thrombolytic therapies in these patients. This study looked at the etiological spectrum of acute stroke mimics presenting within the 4.5 hours therapeutic window. We also evaluated the FAST, BE FAST, and the ROSIER tools in picking true strokes.

Methods:

Prospective study conducted over a 2-year period.

Results:

Acute stroke mimics constituted 328/1635 (20%) of referrals for acute stroke after screening by the neurology stroke team. Focal and generalized seizures with transient weakness and peripheral vertigo were the commonest acute stroke mimics; followed by metabolic causes and psychiatric disorders. Females were more in the stroke mimic group ( P = .02). Ischemic heart disease and atherosclerotic risk factors (except diabetes mellitus) were significantly higher among true strokes. In total, 4 (1.2%) of the stroke mimics were treated with IV thrombolysis. Diagnostic accuracy for different stroke differentiating tools are as follows: FAST (sensitivity 85.9%, specificity 52.8%, odds 6.8), BE FAST (sensitivity 97.0%, specificity 31.4%, odds 14.9), and ROSIER scale (sensitivity 85.7%, specificity 59.4%, odds 8.7%).

Conclusions:

Acute stroke mimics can constitute up to 20% of cases evaluated as acute strokes by neurology stroke teams. None of the triaging tools appear to have enough accuracy. A proper history and clinical examination should be given priority over fixed protocols whenever acute stroke mimic are suspected especially before administering acute costly interventions. Auditing stroke mimics is important to improve acute stroke pathways.
Bridging Therapy and Direct Thrombectomy for Acute Ischemic Stroke: A Prospective Cohort Study
Authors: Nguyen Trung Quoc , Truong Anh Le Tuan , Phan Hoang Thi Kim , Nguyen Duan Duy , Nguyen Khang Vinh , Nguyen Huong Thi Bich , Nguyen An Thanh Thai , Hoang Dinh Chau Bao , Tran Vu Thanh , Nguyen Tri Quang , Le Tra Vu Son , Nguyen Khang Duc , Nguyen Thang Huy
Published: December 2020

Background:

It remains controversial if intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MTE) is superior to MTE alone in patients with acute ischemic stroke caused by large vessel occlusion. We aim to compare functional outcomes, mortality, reperfusion, and intracranial hemorrhage rates in bridging therapy (IVT prior thrombectomy) and MTE alone groups within 6 h from symptom onset.

Materials and Methods:

Consecutive hospitalized patients (September 2017 and July 2018) with acute large artery occlusion within the anterior cerebral circulation eligible for MTE with or without prior IVT were included. A modified Rankin Scale score of 0 to 2 was considered as good functional outcome at 90 days. Successful reperfusion was defined as a Thrombolysis in Cerebral Infarction scale of 2b to 3.

Results:

Of the 124 patients included, 56 (45.2%) received bridging therapy and 68 (54.8%) received MTE alone. Patients receiving bridging therapy were younger (median, 56 vs 63, P = .045) and had shorter onset-to-groin time (median, 270 vs 370 min, P < .001) than those receiving MTE alone. Successful reperfusion rate was significantly greater in the bridging therapy group (87.5% vs 72.1%, P = 0.03). There were no statistically significant differences between the 2 groups in functional independence (bridging 58.9% vs 75.0%, P = 0.07), mortality at 90 days (bridging 14.3% vs 7.4%, P = 0.22), parenchymal hematoma type 2 (bridging 3.6% vs 2.9%, P > .99), and any hemorrhage (bridging 42.3% vs 26.5%, P = 0.07).

Conclusion:

Compared to MTE alone, bridging therapy with IVT improved the reperfusion rate but not other outcomes. Further clinical trials are needed to confirm our findings.
Epidemiology of pleural empyema in English hospitals and the impact of influenza
Authors: Arnold David T. , Hamilton Fergus W. , Morris Tim T. , Suri Tim , Morley Anna , Frost Vicky , Vipond Ian B. , Medford Andrew R. , Payne Rupert A. , Muir Peter , Maskell Nick A.
Published: December 2020

Pleural empyema represents a significant healthcare burden due to extended hospital admissions and potential requirement for surgical intervention. This study aimed to assess changes in incidence and management of pleural empyema in England over the past 10 years and the potential impact of influenza on rates.

Hospital Episode Statistics data were used to identify patients admitted to English hospitals with pleural empyema between 2008 and 2018. Linear regression was used to analyse the relationship between empyema rates and influenza incidence recorded by Public Health England. The relationship between influenza and empyema was further explored using serological data from a prospective cohort study of patients presenting with pleural empyema.

Between April 2008 and March 2018 there were 55 530 patients admitted with pleural empyema. There was male predominance (67%versus33%), which increased with age. Cases have increased significantly from 4447 in 2008 to 7268 in 2017. Peaks of incidence correlated moderately with rates of laboratory-confirmed influenza in children and young adults (r=0.30). For nine of the 10 years studied, the highest annual point incidence of influenza coincided with the highest admission rate for empyema (with a 2-week lag). In a cohort study of patients presenting to a single UK hospital with pleural empyema/infection, 24% (17 out of 72) had serological evidence of recent influenza infection, compared to 7% in seasonally matched controls with simple parapneumonic or cardiogenic effusions (p<0.001).

Rates of empyema admissions in England have increased steadily with a seasonal variation that is temporally related to influenza incidence. Patient-level serological data from a prospective study support the hypothesis that influenza may play a pathogenic role in empyema development.
Near-normal aerobic capacity in long-term survivors after lung transplantation
Authors: Saez-Gimenez Berta , Barrecheguren Miriam , Ramon Maria Antònia , Gomez-Garrido Alba , Bravo Carlos , Monforte Víctor , López-Meseguer Manuel , Berastegui Cristina , Revilla Eva , Romero Christian , Laporta Rosalía , Fernández-Rozas Sonia , Redel-Montero Javier , Solé Amparo , de la Torre Mercedes , Puente Luis , Roman Antonio , Gómez-Ollés Susana , Ojanguren Iñigo
Published: December 2020

The clinical course of lung transplantation (LT) is diverse: some patients present chronic lung allograft dysfunction (CLAD) and progressive decline in pulmonary function, but others maintain normal spirometric values and active lives.

Objectives

The aim of this study was to elucidate whether long-term LT survivors with normal spirometry achieve normal exercise capacity, and to identify predictive factors of exercise capacity.

Methods

This was a cross-sectional multicentre study, where bilateral LT recipients who survived at least 10 years after LT, with normal spirometry, no diagnosis of CLAD and modified Medical Research Council dyspnoea degree ≤2 underwent cardiopulmonary exercise testing (CPET).

Results

28 LT recipients were included with a mean±sdage of 48.7±13.6 years. Oxygen uptake (V′O2) had a mean±sdvalue of 21.49±6.68 mL·kg−1·min−1(75.24±15.6%) and the anaerobic threshold was reached at 48.6±10.1% of theV′O2maxpredicted. The mean±sdheart rate reserve at peak exercise was 17.56±13.6%. The oxygen pulse increased during exercise and was within normal values at 90.5±19.4%. The respiratory exchange ratio exceeded 1.19 at maximum exercise. The median (25–75thpercentile) EuroQol-5D score was 1 (0.95–1), indicating a good quality of life. The median (25–75thpercentile) International Physical Activity Questionnaire score was 5497 (4007–9832) MET-min·week−1with 89% of patients reporting more than 1500 MET-min·week−1. In the multivariate regression models, age, sex and diffusing capacity of the lung for carbon monoxide remained significantly associated withV′O2max(mL·kg−1·min−1); haemoglobin and forced expiratory volume in 1 s were significantly associated with maximum work rate (watts), after adjusting for confounders.

Conclusion

We report for the first time near-normal peakV′O2values during CPET and normal exercise capacity in long-term LT recipients without CLAD.
Distinct immune regulatory receptor profiles linked to altered monocyte subsets in sarcoidosis
Authors: Fraser Simon D. , Crooks Michael G. , Kaye Paul M. , Hart Simon P.
Published: December 2020

Background

In sarcoidosis, blood monocytes, circulating precursors of granuloma macrophages, display enhanced inflammatory cytokine production, reduced expression of the regulatory (inhibitory) receptor CD200R, and altered subsets defined by CD14 and CD16. Regulatory receptors serve to dampen monocyte and macrophage inflammatory responses. We investigated the relationship between monocyte subsets and regulatory receptor expression in sarcoidosis.

Methods

Multiparameter flow cytometry was used to perform detailed analyses of cell surface regulatory molecules on freshly isolated blood immune cells from patients with chronic pulmonary sarcoidosis and age-matched healthy controls.

Results

25 patients with chronic pulmonary sarcoidosis (median duration of disease 22 months) who were not taking oral corticosteroids or other immunomodulators were recruited. Nonclassical monocytes were expanded in sarcoidosis and exhibited significantly lower expression of regulatory receptors CD200R, signal regulatory protein-α and CD47 than classical or intermediate monocytes. In sarcoidosis, all three monocyte subsets had significantly reduced CD200R and CD47 expression compared with healthy controls. A dichotomous distribution of CD200R was seen on classical and intermediate monocytes in the sarcoidosis population, with 14 out of 25 (56%) sarcoidosis patients having a CD200Rlowphenotype and 11 out of 25 (44%) having a CD200Rhighphenotype. These distinct sarcoidosis monocyte phenotypes remained consistent over time.

Conclusions

Nonclassical monocytes, which are expanded in sarcoidosis, express very low levels of regulatory receptors. Two distinct and persistent phenotypes of CD200R expression in classical and intermediate monocytes could be evaluated as sarcoidosis biomarkers.
Accurate machine learning-based germination detection, prediction and quality assessment of three grain crops
Authors: Genze Nikita , Bharti Richa , Grieb Michael , Schultheiss Sebastian J. , Grimm Dominik G.
Published: December 2020

Background

Assessment of seed germination is an essential task for seed researchers to measure the quality and performance of seeds. Usually, seed assessments are done manually, which is a cumbersome, time consuming and error-prone process. Classical image analyses methods are not well suited for large-scale germination experiments, because they often rely on manual adjustments of color-based thresholds. We here propose a machine learning approach using modern artificial neural networks with region proposals for accurate seed germination detection and high-throughput seed germination experiments.

Results

We generated labeled imaging data of the germination process of more than 2400 seeds for three different crops,Zea mays(maize),Secale cereale(rye) andPennisetum glaucum(pearl millet),with a total of more than 23,000 images. Different state-of-the-art convolutional neural network (CNN) architectures with region proposals have been trained using transfer learning to automatically identify seeds within petri dishes and to predict whether the seeds germinated or not. Our proposed models achieved a high mean average precision (mAP) on a hold-out test data set of approximately 97.9%, 94.2% and 94.3% forZea mays,Secale cerealeandPennisetum glaucumrespectively. Further, various single-value germination indices, such as Mean Germination Time and Germination Uncertainty, can be computed more accurately with the predictions of our proposed model compared to manual countings.

Conclusion

Our proposed machine learning-based method can help to speed up the assessment of seed germination experiments for different seed cultivars. It has lower error rates and a higher performance compared to conventional and manual methods, leading to more accurate germination indices and quality assessments of seeds.
Antimicrobial prophylaxis administration after umbilical cord clamping in cesarean section and the risk of surgical site infection: a cohort study with 55,901 patients
Authors:   Swissnoso, Sommerstein Rami , Marschall Jonas , Atkinson Andrew , Surbek Daniel , Dominguez-Bello Maria Gloria , Troillet Nicolas , Widmer Andreas F.
Published: December 2020

Background

The World Health Organization (WHO) recommends administration of surgical antimicrobial prophylaxis (SAP) in cesarean section prior to incision to prevent surgical site infections (SSI). This study aimed to determine whether SAP administration following cord clamping confers an increased SSI risk to the mother.

Methods

Study design: Cohort. Setting: 75 participating Swiss hospitals, from 2009 to 2018. Participants: A total of 55,901 patients were analyzed. Main outcome measures: We assessed the association between SAP administration relative to incision and clamping and the SSI rate, using generalized linear multilevel models, adjusted for patient characteristics, procedural variables, and health-care system factors.

Results

SAP was administered before incision in 26′405 patients (47.2%) and after clamping in 29,496 patients (52.8%). Overall 846 SSIs were documented, of which 379 (1.6% [95% CI, 1.4–1.8%]) occurred before incision and 449 (1.7% [1.5–1.9%]) after clamping (p = 0.759). The adjusted odds ratio for SAP administration after clamping was not significantly associated with an increased SSI rate (1.14, 95% CI 0.96–1.36; p = 0.144) when compared to before incision. Supplementary and subgroup analyses supported these main results.

Conclusions

This study did not confirm an increased SSI risk for the mother in cesarean section if SAP is given after umbilical cord clamping compared to before incision.
Testosterone Replacement Therapy Added to Intensive Lifestyle Intervention in Older Men With Obesity and Hypogonadism
Authors: Barnouin Yoann , Armamento-Villareal Reina , Celli Alessandra , Jiang Bryan , Paudyal Arjun , Nambi Vijay , Bryant Mon S , Marcelli Marco , Garcia Jose M , Qualls Clifford , Villareal Dennis T
Published: December 2020

Background

Obesity and hypogonadism additively contribute to frailty in older men; however, appropriate treatment remains controversial.

Objective

Determine whether testosterone replacement augments the effect of lifestyle therapy on physical function in older men with obesity and hypogonadism.

Design

Randomized, double-blind, placebo-controlled trial.

Setting

VA Medical Center

Participants

83 older (age ≥65 years) men with obesity (body mass index ≥30 kg/m2) and persistently low am testosterone (<10.4 nmol/L) associated with frailty.

Interventions

Participants were randomized to lifestyle therapy (weight management and exercise training) plus either testosterone (LT+Test) or placebo (LT+Pbo) for 6 months.

Outcome Measures

Primary outcome was change in Physical Performance Test (PPT) score. Secondary outcomes included other frailty measures, body composition, hip bone mineral density (BMD), physical functions, hematocrit, prostate specific antigen (PSA), and sex hormones.

Results

PPT score increased similarly in LT+Test and LT+Pbo group (17% vs. 16%; P = 0.58). VO2peak increased more in LT+Test than LT+Pbo (23% vs. 16%; P = 0.03). Despite similar -9% weight loss, lean body mass and thigh muscle volume decreased less in LT+Test than LT+Pbo (-2% vs. -3%; P = 0.01 and -2% vs -4%; P = 0.04). Hip BMD was preserved in LT+Test compared with LT+Pbo (0.5% vs −1.1%; P = 0.003). Strength increased similarly in LT+Test and LT+Pbo (23% vs 22%; P = 0.94). Hematocrit but not PSA increased more in LT+Test than LT+Pbo (5% vs 1%; P < 0.001). Testosterone levels increased more in LT+Test than LT+Pbo (167% vs 27%; P < 0.001).

Conclusion

In older, obese hypogonadal men, adding testosterone for 6 months to lifestyle therapy does not further improve overall physical function. However, our findings suggest that testosterone may attenuate the weight loss–induced reduction in muscle mass and hip BMD and may further improve aerobic capacity.
Anti-Müllerian Hormone Levels in Adolescence in Relation to Long-term Follow-up for Presence of Polycystic Ovary Syndrome
Authors: Caanen Mirte R , Peters Henrike E , van de Ven Peter M , Jüttner Anne M F M , Laven Joop S E , van Hooff Marcel H A , Lambalk Cornelis B
Published: December 2020

Context

Anti-Müllerian hormone (AMH) measured in adolescence as biomarker for prediction of adult polycystic ovary syndrome (PCOS) is doubtful but not substantiated.

Objective

To investigate whether serum AMH levels and other PCOS-associated features in adolescence can predict the presence of PCOS in adulthood.

Design and Setting

A long-term follow-up study based on a unique adolescent study on menstrual irregularities performed between 1990 and 1997.

Participants and interventions

AMH was assayed in 271 adolescent girls. Data on PCOS features were combined with AMH levels. In 160 of the 271 (59%) participants, we collected information in adulthood about their menstrual cycle pattern and presence of PCOS (features) by questionnaire 2 decades after the initial study.

Results

AMH was higher in adolescent girls with oligomenorrhea compared with girls with regular cycles, median (interquartile range): 4.6 (3.1-7.5) versus 2.6 (1.7-3.8) μg/L (P < 0.001). Women with PCOS in adulthood had a higher median adolescent AMH of 6.0 compared with 2.5 μg/L in the non-PCOS group (P < 0.001). AMH at adolescence showed an area under the receiver operating characteristic curve for PCOS in adulthood of 0.78. In adolescent girls with oligomenorrhea the proportion developing PCOS in adulthood was 22.5% (95% CI, 12.4-37.4) against 5.1% (95% CI, 2.1-12.0) in girls with a regular cycle (P = 0.005). Given adolescent oligomenorrhea, adding high AMH as factor to predict adult PCOS or adult oligomenorrhea was of no value.

Conclusions

Adolescent AMH either alone or adjuvant to adolescent oligomenorrhea does not contribute as prognostic marker for PCOS in adulthood. Therefore, we do not recommend routine its use in clinical practice.
Wound-induced polyploidization is dependent on integrin-yki signaling
Authors: Besen-McNally Rose , Gjelsvik Kayla J. , Losick Vicki P.
Published: December 2020

A key step in tissue repair is to replace lost or damaged cells. This occurs via two strategies: restoring cell number through proliferation or increasing cell size through polyploidization. Studies in Drosophila and vertebrates have demonstrated that polyploid cells arise in adult tissues, at least in part, to promote tissue repair and restore tissue mass. However, the signals that cause polyploid cells to form in response to injury remain poorly understood. In the adult Drosophila epithelium, wound-induced polyploid cells are generated by both cell fusion and endoreplication, resulting in a giant polyploid syncytium. Here, we identify the integrin focal adhesion complex as an activator of wound-induced polyploidization. Both integrin and focal adhesion kinase are upregulated in the wound-induced polyploid cells and are required for Yorkie induced endoreplication and cell fusion. As a result, wound healing is perturbed when focal adhesion genes are knocked down. These findings show that conserved focal adhesion signaling is required to initiate wound-induced polyploid cell growth.
Circulating Hedgehog: a fresh view of a classic morphogen
Authors: Prince Elodie , Marcetteau Julien , Thérond Pascal P.
Published: December 2020

Members of the Hedgehog family of morphogens mediate the intercellular communication necessary for the organisation and development of many animal tissues. They are modified by various lipid adducts, rendering them insoluble in hydrophilic environments and leading to the contentious question of how these molecules travel in the aqueous extracellular space. Seminal work carried out by Suzanne Eaton and her colleagues has shed light on how these morphogens can spread over long distances through their association with lipoprotein particles. In this Spotlight article, we discuss Suzanne's pioneering work and her contribution to our understanding of the transport and activity of morphogens, in particular Hedgehog. We also describe two other essential aspects of her work: the discovery and characterisation of endogenously present Hedgehog variants, as well as her proposition that, in addition to its role as a morphogen, Hedgehog acts as an endocrine hormone.
Σχεδιασμός διαμεσικών μαθησιακών περιβαλλόντων για τη συνεκπαίδευση
Authors: Καϊμάρα Πολυξένη , Οικονόμου Ανδρέας , Δεληγιάννης Ιωάννης
Published: December 2020

Η εκπαίδευση των μαθητών με ειδικές εκπαιδευτικές ανάγκες παρουσιάζει ιδιαίτερο ενδιαφέρον, διότι παρόλο που οι μαθητές μπορεί να εμφανίζουν κοινά χαρακτηριστικά σύμφωνα με τη διάγνωσή τους, εντούτοις απαιτεί προσωποποιημένες προσεγγίσεις μάθησης. Η προσωποποιημένη μάθηση είναι μια καινοτόμος τάση σε πολλά εκπαιδευτικά περιβάλλοντα, όπως είναι και τα περιβάλλοντα συνεκπαίδευσης, η οποία προϋποθέτει την προσαρμογή των μεθόδων διδασκαλίας. Οι μέθοδοι αυτές πληρούν τις απαιτήσεις της παιδαγωγικής του 21ου αιώνα, της διαφοροποιημένης παιδαγωγικής και των αρχών του καθολικού σχεδιασμού για τη μάθηση. Για το βέλτιστο αποτέλεσμα μιας σύγχρονης παιδαγωγικής προσέγγισης είναι απαραίτητη η αξιοποίηση της σύγχρονης τεχνολογίας, με προσιτό εξοπλισμό, όπως είναι τα tablets και τα smartphones, και εύκολες στη χρήση εφαρμογές, οι οποίες μπορούν να υποστηρίξουν εκπαιδευτικούς και μαθητές οπουδήποτε και οποτεδήποτε. Με δεδομένο ότι οι εκπαιδευτικοί θεωρούνται ο μοχλός κάθε εκπαιδευτικής καινοτομίας, λαμβάνονται υπόψη οι απόψεις τους αναφορικά με τα εμπόδια για την εισαγωγή ψηφιακών μαθησιακών εργαλείων στην τάξη, όπως είναι η έλλειψη κατάρτισης, εξοπλισμού και εκπαιδευτικού υλικού. Υπό αυτό το πρίσμα, η συγγραφική ομάδα στο παρόν άρθρο παρουσιάζει πρακτικές σχεδιασμού και ανάπτυξης εφαρμογών βασισμένες στην τεχνολογία αιχμής, όπως είναι η επαυξημένη πραγματικότητα, που σε συνδυασμό με τα παραδοσιακά puzzles και τις τεχνικές της παιχνιδοποίησης ορίζουν το πεδίο της διαμεσικής μάθησης.
FOMENTAR LA AUTONOMÍA EN EL APRENDIZAJE DE SEGUNDAS LENGUAS: DIARIO DEL PROYECTO APLA EN LA US
Authors: Martos Ramos José Javier , Trapassi Leonarda
Published: December 2020

En el presente artículo se aborda la cuestión de cómo un centro de recursos puede fomentar un comportamiento autónomo y promover el uso consciente de estrategias entre los aprendientes de segundas lenguas. Partiendo del Centro APLA, Centro de Aprendizaje Lingüístico Autónomo de la Facultad de Filología de la US, creado a finales de 2018, se describen las diferentes actividades que se han llevado a cabo desde su fundación, y las razones para fomentar la autonomía. Se hace hincapié en las estrategias metacognitivas, cognitivas y socioafectivas como forma más adecuada para este propósito. Finalmente se plantea una desiderata y varias líneas de trabajo futuras de APLA.
USING LOGBOOKS WITH SECOND AND FOREIGN LANGUAGE LEARNERS IN HIGHER EDUCATION: LEARNER AUTONOMY IN PROGRESS
Authors: Menegale Marcella
Published: December 2020

This paper reports data from a study recently carried out with university language students attending a Master’s degree programme in Language Sciences. The study aimed at exploring to what extent logbook writing could allow them to progress in their learner autonomy by engaging in more reflective, conscious, and responsible second/foreign language learning. The class was asked first to write a logbook for a week with the purpose of keeping track of their personal language learning process and then to answer some reflective questions to give an account of their perception about the logbook experience. By taking an interpretive approach to the investigation and adopting qualitative data analysis, it was found that the logbook was generally perceived as useful in improving language learning and stimulating meta-cognitive reflection, self-awareness and learner’s intervention. While limits were identified in the use of this tool (i.e., persistence needed to regularly keep logs, time availability and appropriate organisation skills), some students declared their intention to use the logbook in the future, after making personalised adjustments according to their learning needs and goals.
645. Los «bancos malos» y la resolución de la crisis financiero-inmobiliaria en Europa
Authors: Byrne Michael
Published: December 2020

Este artículo se centra en las Sociedades de Gestión de Activos (SGA), o «bancos malos», creadas por parte de los gobiernos para adquirir y gestionar activos improductivos, a menudo vinculados con el sector inmobiliario, tras las crisis bancarias sistémicas. A pesar de que las SGA son entidades financieras muy importantes y con claras implicaciones urbanas, han recibido más bien poca atención. Este artículo examina ciertas SGA que se han creado dentro de Europa como parte de las respuestas de estados miembros e instituciones europeas a la crisis bancaria. Las SGA han sido uno de los principales mecanismos establecidos en Europa para lidiar con problemas de solvencia y activos improductivos en el sistema financiero. Desde 2010, se han creado más de doce instituciones de este tipo que gestionan miles de millones de euros en activos inmobiliarios. El artículo analiza las SGA desde cuatro perspectivas para comprender sus dimensiones específicamente urbanas. En primer lugar, las SGA siguen con la extracción financiarizada de valor del espacio urbano. En segundo lugar, actúan como «creadores de mercados» al devolver «liquidez» al sector inmobiliario. En tercer lugar, contribuyen a la globalización del sector inmobiliario al intensificar los circuitos que vinculan los mercados inmobiliarios locales con flujos globales de capital. Por último, generan contestación política en torno al acceso a y el control sobre el espacio urbano.
642. Discursos penitenciarios, encierros y celdas: las Cárceles Modelo de Madrid y Barcelona.
Authors: Fraile Pedro
Published: December 2020

En junio de 2017, la Cárcel Modelo de Barcelona se vació de reclusos, lo que parecía señalar el fin de un prototipo edificatorio (la planta estrellada, que tuvo una difusión notable durante los siglos XIX y XX), así como el de una confusa y dubitativa relación del encierro con el tejido urbano. A lo largo del ochocientos español hubo una serie de tanteos para abordar una reforma penitenciaria que ya avanzaba en otros lugares de Europa. Veremos el esfuerzo realizado, pero también la penuria de los logros obtenidos, salvo excepciones, en ese camino. Ese proceso culminó, en cierto sentido, con la elevación de tres grandes cárceles Modelo: la de Madrid, la de Barcelona y la de Valencia. En estas páginas nos ocuparemos de las dos primeras, integrándolas en esa dinámica destinada a poner en marcha la reforma penitenciaria, de la cual, estos establecimientos deberían ser un motor privilegiado.
651. “En lugar de pagar un coyote a los Estados Unidos creamos nuestro lugar”. Redes de comercio popular maya k´iche´ en la producción de espacios transfronterizos México-Guatemala
Authors: Gracia María Amalia , Díaz Perera Miguel Angel , Roldán Rueda Héctor Nicolás
Published: December 2020

Los cruces y espacios fronterizos que México comparte con Guatemala son escenarios dinámicos de cambio social. Junto a las oleadas de tránsito migratorio hacia Estados Unidos, existen procesos transfronterizos invisilizados que en las últimas décadas han ido transformando aceleradamente estos espacios. Mediante técnicas predominantemente cualitativas, reconstruimos la conformación de la zona comercial El Ceibo-Frontera constituida por migrantes internos guatemaltecos mayas k´iche´ e identificamos los factores sociales, políticos y culturales involucrados, mostrando las fortalezas y tensiones para su consolidación.
648. La aportación a la ciencia climática de A. de Humboldt en el Cosmos
Authors: Olcina Cantos Jorge
Published: December 2020

La consolidación de la climatología como disciplina científica conoce un impulso decisivo con los trabajos de Alejandro de Humboldt, en las primeras décadas del siglo XIX. Los avances experimentados en la edad Moderna, merced al conocimiento directo del ámbito intertropical y de los vientos que favorecían la navegación marítima transoceánica (alisios), alcanzan en los trabajos de Humboldt la categoría de ciencia al aplicar un método científico basado en el uso de datos anotados en los observatorios meteorológicos, las localización cartográfica de sus valores medios (isotermas) y la comparación con registros o fenómenos atmosféricos ocurridos en diferentes territorios de latitud similar. Todo ello permite configurar un corpus teórico que alimentará su concepción geográfica basada en un conocimiento detallado e integrador de la superficie terrestre, donde el medio físico, con todos los elementos que lo componen, es soporte de las actuaciones del ser humano. Así se recogerá en su obra cumbre Cosmos, que reúne las ideas y resultados de investigación del geógrafo alemán. Humboldt puede ser considerado como el primer climatólogo científico que cultiva una climatología geográfica, que se va desprendiendo de ideas y creencias anteriores merced a la aplicación de un método científico, al que ayuda a definir y aplicar.
Cross-spectral purity of nonstationary vector fields in space–time and space–frequency domains
Authors: Joshi Rajneesh , Kanseri Bhaskar
Published: December 2020

We establish the concept of cross-spectral purity for nonstationary electromagnetic fields having any degree of coherence or polarization. The conditions of cross-spectral purity in all Stokes parameters are derived for both space–time and space–frequency domains, which demonstrate that the normalized two-point coherence properties of such fields can be expressed as products of a spatial and a time (or frequency) dependent function. We further determine the condition of strict cross-spectral purity for nonstationary fields, which establishes the equivalence of normalized two-point Stokes parameters governing the spatial factors of the space–frequency and space–time domains. This study may provide interesting aspects of statistical properties of beams obtained from practically available sources such as pulsed lasers, modulated and fluctuating light sources, etc.
3D printed millimeter-wave beam-steering reflector using dielectric fluids
Authors: Ruphuy Miguel , Saavedra Carlos E.
Published: December 2020

A three-dimensional printed beam-steering reflector surface with dielectric fluids as the tuning agent is presented. The reflector is made using ECO-ABS with six rows of 19 parallel channels of square cross-sections. The permittivity of the ECO-ABS was measured at 2.55 with a loss tangent of 0.053. A conductor is placed at the back of the dielectric. The squared channels are filled with either distilled water or air. The effective permittivity within the reflector changes according to the material used to fill the channels. As an incident wave propagates through the printed dielectric, the configuration of air–water channels shapes the exiting phase front of the wave by locally controlling its phase delay. The resulting phase profile created by the air–water configuration leads to a steered beam. Numerical full-wave simulations show steerable angles ranging from

−

42
∘

to 23° for a set of air–water configurations at 30 GHz. A prototype was fabricated and tested for the same configurations. Experiments confirm a wide range of angles starting at

−

40
∘

up to 20°.
Bilayer terahertz chiral metasurfaces with different dihedral symmetries
Authors: Masyukov Maxim , Grebenchukov Alexander N. , Vozianova Anna V. , Khodzitsky Mikhail K.
Published: December 2020

In this paper, we discuss the isotropic chiroptical response of two-layered metasurfaces with

n

-fold dihedral symmetries of resonators (

D
n

) in the terahertz (THz) range. The analysis of numerical calculations is based on the homogenization model through effective polarizability approximation. We reveal the impact of resonator symmetry on circular dichroism and polarization anisotropy of the metasurface. In particular, it is shown that an increase in the symmetry order of a metasurface unit cell leads to a proportional resonance red shift in circular dichroism spectra. This research has both fundamental and applied relevance, and may enable the realization of THz devices capable of polarization manipulation or possessing polarization sensitive features.
Correction of static and non-common path aberrations in an adaptive optics system using inherent calibration data
Authors: Knutsson Per , Thaung Jörgen , Owner-Petersen Mette , Popović Zoran
Published: December 2020

For low-order adaptive optics systems, a method that is able to correct for system aberrations in the final focal plane is presented. The paper presents a novel figure of merit, corresponding to the integrated non-normalized tip-tilt-free optical transfer function. The inherent singular value decomposition modal content of the interaction matrix is used to optimize this figure of merit. The method has proven to be stable and robust, providing a simple mean to facilitate diffraction limited imaging in an experimental setup for ophthalmic applications.
Sub-micron picoplankton shape, orientation, and internal structure combined to preferentially amplify the forward scatter
Authors: Smyth T. J. , Tarran G. A. , Sathyendranath S.
Published: December 2020

Compelling evidence is presented that sub-micron picoplankton shape, internal structure and orientation in combination leads to a disproportionate enhancement of differential forward scatter compared with differential side scatter when analyzed with a flow cytometer. Theoretical evidence is provided which results in an order of magnitude amplification in the forward scatter direction, with little or no change in the side scatter: this discounts the possibility of “doublets” caused by multiple particles simultaneously present in the laser beam. Observational evidence from progressively finer filtered seawater samples shows up to three orders of magnitude enhancement in the forward scatter direction and sizes of Prochlorococcus close to that reported in the literature (0.61 ± 0.17 µm). It therefore seems likely that flow cytometrically observed “bi-modal size distributions” of Prochlorococcus are instead the manifestation of intra-population differences in shape (spherical – prolate with preferential alignment) and internal structure (homogenous – heterogenous).
High efficiency active Q-switched laser operation with a large size rectangular core crystalline waveguide
Authors: Hui YongLing , Liu Qi , Hu Xing , Zhu Zhanda , Lei Hong , Li Qiang
Published: December 2020

High efficient pulse output from a large size rectangular core crystalline waveguide actively Q-switched laser was achieved experimentally. A crystalline waveguide, with a rectangular core size of 320μm×400μm by 1.0at.% Yb:YAG (core), 600μm×600μm by 0.5at.% Er:YAG (cladding), and 7mm×7mm by 4.0at.% V:YAG (outside of the cladding) was designed and fabricated. Using a continuous diode laser as an end pump, an output pulse energy 1.75mJ@10kHz, pulse width 9.9ns (peak power 175kW), optical-optical efficiency 26%, with the beam quality of Mx2=1.15, My2=1.10, were obtained in the experiment. The design method that used to suppress amplified spontaneous emission (ASE) and parasitic oscillation by cutting off the reflection and transmission paths, can be applied for various kinds of crystalline waveguide Q-switched or mode-locked lasers.
Zoom liquid lens employing a multifocal Fresnel zone plate
Authors: Li Lei , Kuang Feng-Lin , Wang Jin-Hui , Zhou Yin , Wang Qiong-Hua
Published: December 2020

We propose a zoom liquid lens employing a multifocal Fresnel zone plate. The proposed lens has two optical surfaces: liquid-liquid interface and Fresnel zone plate. The Fresnel zone plate is designed to have a multifocal point and an increased depth of focus. Therefore, the proposed lens has two obvious advantages. Due to increased depth of focus, the proposed lens can realize zooming using only one tunable liquid-liquid interface, which is not available for conventional liquid lens. Thus, it is possible to remove conventional zooming mechanisms from cameras. Besides, the focal length tuning range is also increased, and a lens system based on the proposed lens can simultaneously collect two images with different magnifications. We present the design, fabrication and characterization of the proposed lens. The shortest positive and negative focal length are ∼17.5mm and ∼−34.5mm and the diameter is 5mm. The zoom ratio of the proposed lens reaches ∼1.48×. Our results confirm that the proposed lens has widespread applications in imaging system.
Reconfigurable silicon bandpass filters based on cascaded Sagnac loop mirrors
Authors: Ge Renyou , Luo Yannong , Gao Shengqian , Han Ya , Chen Lifeng , Cai Xinlun
Published: December 2020

We demonstrate a high-performance reconfigurable bandpass filter implemented by cascaded Sagnac loop mirror (SLM)-based coupled resonator optical waveguides (CROWs) on the silicon-on-insulator platform. By dynamic thermal tuning of the reflectivity in each SLM, the proposed filter can achieve simultaneous 3 dB bandwidth tuning from 8.50 to 20.25 GHz and a central wavelength tuning range of 216.25 GHz. A box-like filtering response with an ultra-high extinction ratio up to 70 dB and an ultra-sharp roll-off of 0.61 are observed in a 6th-order SLM-coupled resonator optical waveguide (SLM-CROW). The proposed reconfigurable SLM-CROW filter can satisfy the demand for next-generation flexible-grid WDM networks.
Thermally chirped contra-directional couplers for residueless, bandwidth-tunable Bragg filters with fabrication error compensation
Authors: Cauchon Jonathan , St-Yves Jonathan , Shi Wei
Published: December 2020

Bandwidth-tunable filters are essential in elastic optical networks for dynamic bandwidth allocation. Existing solutions in silicon photonics face challenges to meet requirements in real-world applications due to design trade-offs and fabrication errors. In this Letter, we propose and experimentally demonstrate a silicon photonic tunable add-drop filter in a single-stage, hyperbolic-tangent-apodized contra-directional coupler with a segmented microheater. It allows to create an arbitrary temperature profile along the device for bandwidth tuning in both through and drop responses. We show that the algorithmic operation of the device can effectively compensate local fabrication nonuniformity and improve the out-of-band suppression ratio by 69%. Applying proper temperature offsets and slopes allows to continuously tune the filter’s center wavelength over 8 nm and its drop-port 3 dB bandwidth between 14.0 and 22.4 nm.
Field aberrations in terms of the Q-polynomial basis and its relationship to the Zernike basis
Authors: García-Moreno Andrea , Restrepo René , Belenguer-Dávila Tomás , González-Fernández Luis M.
Published: December 2020

The aberrations generated at the image plane of an optical system that includes freeform surfaces described through Q-polynomials can be calculated using nodal aberration theory. By analyzing the definition of each Q-polynomial, they can be compared with Zernike polynomials allowing a relationship between the two bases. This relationship is neither simple nor direct, so a fitting must be made. Once established, the contribution to the aberration field map generated by each surface described through the Q-polynomial can be calculated for any surface that is not at the stop of the system. The Q-polynomials are characterized by their orthogonality in the gradient instead of the surface, which represents an opportunity to restrict the changes in the slope in a simple way and facilitate the manufacturing process. The knowledge of the field aberrations generated by each Q-polynomial allows selecting that which of them are necessary to be introduced as variables in the optimization process for an efficient optimization.
Quantum correlating measurements of human-body delayed luminescence and preliminary experimental results
Authors: Zhang Xiaochun , Zheng Peng , Yang Yongdong , Wang Jing , Zhao Minyi , Gu Feifei , Gao Peng , Jiang Meili , Liu Yang , Tang B. Qing
Published: December 2020

Biological delayed luminescence (DL) refers to the emission of photons of 200-800 nm after an organism is exposed to a beam of light. At present, DL research is mostly conducted on plants and cells. Most human research uses low-temperature photomultiplier tubes (PMT) with poor performance. This paper introduces a newly developed dual-channel, coincident counting DL acquisition system, as well as preliminary experimental results with acupuncture meridians and acupoints in humans. The system employs two low-noise SPAD (single photon avalanche diode) modules to achieve not only a time resolution as low as 1 μs, but also a spatio-temporal correlation relation between two simultaneous measurements. Using a laser excitation of 400 nm and 532 nm, we measured the DL emission for different parts of the human body and found that the corresponding DL curves follow the hyperbolic law of

I
=

I
0

(

1
+

t
τ

)

−
γ

. The emission curves are sensitive to many factors including the current health state of the participants. We hypothesize that DL emission is a quantum process involving a variety of functional biomolecules in the human body, and that various DL curve parameters could reflect information about human health and disease. We predict that quantitative analysis, based on accurately measured DL emission, will provide a powerful new tool for monitoring human health in the future.
Myths, misconceptions, othering and stigmatizing responses to Covid-19 in South Africa: A rapid qualitative assessment
Authors: Schmidt Tenielle , Cloete Allanise , Davids Adlai , Makola Lehlogonolo , Zondi Nokubonga , Jantjies Monalisa
Published: December 2020

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a new strain of virus in the Coronavirus family that has not been previously identified. Since SARS-CoV-2 is a new virus, everyone is at risk of catching the Coronavirus disease 2019 (Covid-19). No one has immunity to the virus. Despite this, misconceptions about specific groups of people who are immune to Covid-19 emerged with the onset of the pandemic. This paper explores South African communities’ misconceptions about who is most vulnerable to Covid-19. A rapid qualitative assessment was conducted remotely in Gauteng, KwaZulu-Natal and the Western Cape provinces of South Africa. Recruitment of study participants took place through established relationships with civil society organizations and contacts made by researchers. In total, 60 key informant interviews and one focus group discussion was conducted. Atlas.ti.8 Windows was used to facilitate qualitative data analysis. The qualitative data was coded, and thematic analysis used to identify themes. The results show a high level of awareness and knowledge of the transmission and prevention of SARS-CoV-2. Qualitative data revealed that there is awareness of elderly people and those with immunocompromised conditions being more vulnerable to catching Covid-19. However, misconceptions of being protected against the virus or having low or no risk were also evident in the data. We found that false information circulated on social media not only instigated confusion, fear and panic, but also contributed to the construction of misconceptions, othering and stigmatizing responses to Covid-19. The study findings bring attention to the importance of developing communication materials adapted to specific communities to help reduce misconceptions, othering and stigmatization around Covid-19.
Prevalence of Salmonella contamination in consumed eggs in Iran: A systematic review and meta-analysis study on published studies from 1996 to 2018
Authors: Hosseininezhad Behnam , Berizi Enayat , Nader Marzieh , Mazloomi Seyed Mohammad , Hosseinzadeh Saeid , Ebrahimi Laya , Zare Morteza
Published: December 2020

Background and Aim: Food poisoning caused by Salmonella is among the most common gastrointestinal discomfort resulted from egg consumption which can produce various syndromes. The present study is a systematic review and metaanalysis investigation on the published studies about the prevalence of Salmonella contamination in the consumed eggs in Iran.

Materials and Methods: The data were collected and analyzed from four international search databases, including PubMed, Scopus, Science Direct, and Google Scholar and four Iranian databases comprising SID, MagIran, Civilica, and IranDoc. After searching all the databases, 303 articles were found, from which 31 articles were included in the final analysis.

Results: According to the data analysis, the highest rate of contamination was belonged to the industrial eggs (7.49%), however, the prevalence rate was reported 13.61% in the eggshell part. The overall prevalence of Salmonella contamination in consumed eggs of Iran using culture of microbial, molecular, molecular-serological, culture-molecular, cultureserological, and culture -molecular-serological methods was obtained 11.33%, 5.52%, 0.37%, 1.91%, 5.52%, and 0.73%, respectively. Prevalence in the 21 geographical areas, where studies have been conducted, ranged from 0% (Zahedan) to 29.06% (Tabriz). The studies have also showed that eight different serotypes were among the major cause of Salmonella contamination in eggs. The most common Salmonella serotype was Salmonella Enteritidis and the highest diversity in Salmonella contaminant serotypes was recorded in Talesh (including S. Enteritidis, Salmonella Gallinarum, Salmonella Virchow, and Salmonella Newport).

Conclusion: Results of this study revealed the high prevalence of Salmonella contamination in eggs, in Iran. Therefore, disinfection and cleaning bed, cleaning of equipment and supplies, and proper maintenance temperature and humidity of the eggs are recommended. In addition, proper personal hygiene and prohibition of consuming raw egg products are essential.