bluuebunny/crossref_metadata_2025 huggingface dataset:
Ανάπτυξη μεθοδολογίας επίλυσης προβλημάτων ορισμού και εξέλιξης διοικητικών ορίων σε χωροχρονική κλίμακα
Authors: Σταύρου Χρήστος
Published: February 2022

Η παρούσα διατριβή, σε πρώτη ανάγνωση,είναι και ένα ταξίδι στην ιστορία. Η Ελλάδα, ως κρατική οντότητα, διένυσε μία μακρά ιστορική διαδρομή μέχρι να λάβει την οριστική της μορφή. Η πορεία αυτή, σε σχέση με τις εκάστοτε διοικητικές της διαιρέσεις, τον θεσμικό ορισμό, την οριοθέτηση αλλά και την χαρτογραφική τους απεικόνιση αποδείχθηκε προβληματική. Η έλλειψη σαφούς προσδιορισμού αρμοδιοτήτων των εμπλεκομένων, τυποποίησης ορολογίας και διαδικασίας, κοινά αποδεκτής εθνικής κωδικοποίησης, πλήρως ενημερωμένου και προσβάσιμου αρχείου αποφάσεων καθορισμού διοικητικών ορίων, τα κατά συνέπεια κενά στο θεσμικό πλαίσιο, σε συνδυασμό με την απουσία συστηματικής μεθοδολογίας για τον ορισμό, την εξέλιξή τους και την τήρηση αρχείου μεταβολών σε χωροχρονική κλίμακα αποτελούν σημαντικό ερευνητικό αντικείμενο και θέμα της παρούσας διατριβής.Η καταγραφή της ιστορικής εξέλιξης του ζητήματος,ταξινομημένης σε περιόδους αναφοράς ανάλογες της διοικητικής ιστορίας του ελληνικού κράτους, η ανάλυση του προβλήματος και των αιτιών του παρείχαν τη δυνατότητα καθορισμού των κύριων προτεραιοτήτων και της συστηματοποίησης στην αντιμετώπιση του. Άλλωστε, στη συστηματοποίηση αυτή στηρίχθηκε η ανάπτυξη μεθοδολογίας που θα έχει γενική εφαρμογή και θα δίνει λύση στο πρόβλημα. Βασίζεται στη χωροχρονική οργάνωση των στοιχείων (νομικά έγγραφα, χάρτες) με τη μορφή ενιαίας γεωχωρικής βάσης δεδομένων, παρέχει το στοιχείο της ιστορικότητας με την τήρηση αρχείου μεταβολών, επιλέγει την κωδικοποίηση των γεωχωρικών δεδομένων με τρόπο που καθιστά εφικτή την συγκρισιμότητά τους και την σύνδεση με το φορέα του κτηματολογίου, ενσωματώνει μηχανισμό ενημέρωσης των μελλοντικών μεταβολών και θα αποτελεί το σημείο αναφοράς για τους χρήστες (δημόσιους φορείς και ιδιώτες) και την εκπλήρωση των διεθνών τους υποχρεώσεων με την θεσμική της κατοχύρωση.
External stressors prior to traumatic knee injury: A cohort study on youth athletes.
Authors: Ryman Augustsson Sofia , Lundquist Petra
Published: February 2022

Background:Data on external stressors, such as social and environment variables and other "life events", and its relation to injury in youth athletic population are scarce. Investigating if external stressors is associated with injury risk may help coaches and other team staff to provide a more safe sport environment. The aim of the present study was to evaluate different aspects of external stressors and its potential association to traumatic knee injury in youth athletes.

Methods:This study comprised of youth female and male athletes from Swedish national sports high schools, aged 15–19 years, participating and competing in soccer, handball, or floorball. The athletes recorded any traumatic knee injury that had occurred during high-school in a web-based injury form. Data on external stressors and subjective perceived stress was also collected.

Results:The majority (60%) of stress factors noted was related to sport context. More athletes in the injured group of athletes reported life event stressor (p=0.001) and experienced stress more often (p=0.02) compared to the group of non-injured athletes. No differences between injured and non-injured athletes in terms of change of club, team coach, training protocol or game formation were noted (p>0.05). A weak correlation (r=0.20, p=0.02) was found between the number of stressors and injuries.

Conclusions:A high prevalence of external stressors are present in youth elite athletes with a majority of stress factors related to sport context. Life event stressors are present prior to injury and seem to be associated with traumatic knee injury to some degree.
The utility of repeat Xpert MTB/RIF testing to diagnose tuberculosis in HIV-positive adults with initial negative result
Authors: Hanifa Yasmeen , Fielding Katherine L. , Chihota Violet N. , Adonis Lungiswa , Charalambous Salome , Foster Nicola , Karstaedt Alan , McCarthy Kerrigan , Nicol Mark P. , Ndlovu Nontobeko T. , Sinanovic Edina , Sahid Faieza , Stevens Wendy , Vassall Anna , Churchyard Gavin J. , Grant Alison D.
Published: February 2022

Background: Amongst HIV-positive adults in South Africa with initial negative Xpert results, we compared the yield from repeating Xpert MTB/RIF (“Xpert”) on sputum to guideline-recommended investigation for tuberculosis (TB).

Methods:  A systematic sample of adults attending for HIV care were enrolled in a cohort exploring TB investigation pathways. This substudy was restricted to those at highest risk of TB (CD4<200 cells/mm3 or unknown) who had a negative initial Xpert result.

At attendance for the Xpert result, a repeat sputum sample was stored, and further investigations facilitated per national guidelines. Participants were reviewed monthly, with reinvestigation if indicated, for at least three months, when sputum and blood were cultured for mycobacteria, and the stored sputum tested using Xpert. We defined TB as “confirmed” if Xpert, line probe assay or Mycobacterium tuberculosis culture within six months of enrolment were positive, and “clinical” if TB treatment was started without microbiological confirmation.

Results: Amongst 227 participants with an initial negative Xpert result (63% female, median age 37 years, median CD4 count 100 cells/mm3), 28 (12%) participants had TB diagnosed during study follow-up (16 confirmed, 12 clinical); stored sputum tested positive on Xpert in 5/227 (2%). Amongst 27 participants who started TB treatment, the basis was bacteriological confirmation 11/27 (41%); compatible imaging 11/27 (41%); compatible symptoms 2/27 (7%); and unknown 3/27 (11%). 

Conclusions:  Amongst HIV-positive individuals at high risk of active TB with a negative Xpert result, further investigation using appropriate diagnostic modalities is more likely to lead to TB treatment than immediately repeating sputum for Xpert. TB diagnostic tests with improved sensitivity are needed.
Do differentiated service delivery models for HIV treatment in sub-Saharan Africa save money? Synthesis of evidence from field studies conducted in sub-Saharan Africa in 2017-2019
Authors: Rosen Sydney , Nichols Brooke , Guthrie Teresa , Benade Mariet , Kuchukhidze Salome , Long Lawrence
Published: February 2022

Introduction: “Differentiated service delivery” (DSD) for antiretroviral therapy (ART) for HIV is rapidly being scaled up throughout sub-Saharan Africa, but only recently have data become available on the costs of DSD models to healthcare providers and to patients. We synthesized recent studies of DSD model costs in five African countries.

Methods: The studies included cluster randomized trials in Lesotho, Malawi, Zambia, and Zimbabwe and observational studies in Uganda and Zambia. For 3-5 models per country, studies collected patient-level data on clinical outcomes and provider costs for 12 months. We compared costs of differentiated models to those of conventional care, identified drivers of cost differences, and summarized patient costs of seeking care.

Results: The studies described 22 models, including conventional care. Of these, 13 were facility-based and 9 community-based models; 15 were individual and 7 group models. Average provider cost/patient/year ranged from $100 for conventional care in Zambia to $187 for conventional care with 3-month dispensing in Zimbabwe. Most DSD models had comparable costs to conventional care, with a difference in mean annual cost per patient ranging from 11.4% less to 9.2% more, though some models in Zambia cost substantially more. Compared to all other models, models incorporating 6-month dispensing were consistently slightly less expensive to the provider per patient treated. Savings to patients were substantial for most models, with patients’ costs roughly halved.

Conclusion: In five field studies of the costs of DSD models for HIV treatment, most models within each country had relatively similar costs to one another and to conventional care. 6-month dispensing models were slightly less expensive, and most models provided substantial savings to patients. Limitations of our analysis included differences in costs included in each study. Research is needed to understand the effect of DSD models on the costs of ART programmes as a whole.
Chromosome-scale assembly of the yellow mealworm genome
Authors: Eleftheriou Evangelia , Aury Jean-Marc , Vacherie Benoît , Istace Benjamin , Belser Caroline , Noel Benjamin , Moret Yannick , Rigaud Thierry , Berro Fabrice , Gasparian Sona , Labadie-Bretheau Karine , Lefebvre Thomas , Madoui Mohammed-Amin
Published: February 2022

Background: The yellow mealworm beetle, Tenebrio molitor, is a promising alternative protein source for animal and human nutrition and its farming involves relatively low environmental costs. For these reasons, its industrial scale production started this century. However, to optimize and breed sustainable new T. molitor lines, the access to its genome remains essential.

Methods: By combining Oxford Nanopore and Illumina Hi-C data, we constructed a high-quality chromosome-scale assembly of T. molitor. Then, we combined RNA-seq data and available coleoptera proteomes for gene prediction with GMOVE.

Results: We produced a high-quality genome with a N50 = 21.9Mb with a completeness of 99.5% and predicted 21,435 genes with a median size of 1,780 bp. Gene orthology between T. molitor and Tribolium castaneaum showed a highly conserved synteny between the two coleoptera and paralogs search revealed an expansion of histones in the T. molitor genome.

Conclusions: The present genome will greatly help fundamental and applied research such as genetic breeding and will contribute to the sustainable production of the yellow mealworm.
Patrimonio nuclear del sur de España. Diagnóstico y propuestas.
Authors: Muñoz-Castillo Juan Antonio , Olcina-Cantos Jorge
Published: February 2022

El presente trabajo es una puesta al día del patrimonio nuclear existente en el sur de España. Las antiguas minas de uranio, las fábricas de combustible nuclear, los almacenes de residuos nucleares o los lugares afectados por accidentes nucleares tienen un conjunto de posibilidades por encima de su relación con la actividad del uranio. Se analiza y valora el estado de las instalaciones nucleares existentes en el sur de España que forman un conjunto patrimonial que merece atención institucional y puede tener oportunidades para su trasformación en recurso de aprovechamiento docente o turístico. Del análisis detallado de cada elemento del objeto de estudio, se ha pasado a establecer el diagrama de fortalezas y debilidades del conjunto. El patrimonio nuclear analizado sufre una estigmatización que se debe revertir a partir de una serie de acciones conducentes al desarrollo de las localidades afectadas, en una serie de acciones conducentes de modo sostenible a integrarles en sus entornos regionales.
Classificação do sistema de trilhas da unidade de conservação Parque Estadual Mata do Pau-Ferro, Areia, Paraíba, Brasil.
Authors: Porto de Lima Valeria Raquel , Oliveira-Campos Jean
Published: February 2022

A Unidade de Conservação (UC) Parque Estadual Mata do Pau-Ferro está localizada no município de Areia, estado da Paraíba, Nordeste do Brasil. A UC não possui um sistema de trilhas detalhado. Diante do exposto, o presente artigo elaborou um mapeamento das trilhas mais usadas pelos turistas que frequentam o Parque. Os procedimentos metodológicos consistiram no registro das coordenadas das trilhas usando um Sistema de Posicionamento Global – GPS e capturas fotográficas dos principais atrativos ao longo dos trajetos. Além disso, com o uso do software ArcGIS 10.2, as variáveis ambientais declividade, condições de terreno, cobertura vegetal e drenagem foram somadas para obter as classes de dificuldade das trilhas, usando como referências Silva (2016), Silva, Lima & Panchaud (2016), e Silva & Palhares (2020). Como resultado, foram mapeadas 4 trilhas, 2 integrações e 4 pontos principais que funcionam como atrativos turísticos. Em relação às classes de dificuldade das trilhas, 67,41% do sistema de trilhas foi classificado como “fácil”, contexto que evidencia potencial para receber um público diverso de visitantes.
Resiliencia del mercado turístico urbano ante la crisis de la COVID-19. El caso de Málaga.
Authors: Benítez-Aurioles Beatriz
Published: February 2022

Este artículo tiene como objetivo verificar la resiliencia del turismo urbano ante la crisis de la COVID-19 e identificar sus rasgos principales, tomando como referencia la ciudad de Málaga. Se utilizará el enfoque metodológico que proporciona el análisis económico para analizar la dinámica que se ha registrado en el mercado de alojamientos, tanto convencionales (hoteles) como el de viviendas turísticas de alquiler a corto plazo. Los datos se refieren a indicadores de demanda, de oferta y de precios para el periodo comprendido entre septiembre de 2018 y el mismo mes del año 2021. Los resultados del análisis evidencian claros signos de recuperación del mercado turístico a partir de la primavera de 2021. Más concretamente, se constata el protagonismo que adquieren los residentes en España en la demanda de alojamiento hotelero. Asimismo, en el mercado peer-to-peer se confirma que, meses después del levantamiento de las restricciones a la movilidad, se superaron los niveles de actividad alcanzados antes de la pandemia. Sobre esa base, parece pertinente reabrir y replantear el debate sobre la capacidad de carga de las ciudades y la conveniencia de regular el mercado de alojamientos turísticos.
Cambios observados y proyectados en los tipos de regímenes bioclimáticos de Argentina.
Authors: Soledad Duval Valeria , Cámara-Artigas Rafael
Published: February 2022

El estudio de los límites bioclimáticos es esencial en cada región para conocer la distribución de las formaciones vegetales. El objetivo del trabajo fue elaborar mapas bioclimáticos de Argentina en tres períodos de tiempo (Ultimo Máximo Glaciar, actualidad y escenario de cambio climático RCP8.5 del 2070) y analizar sus cambios. Para ello, se aplicó la metodología de los tipos de regímenes bioclimáticos a partir de bases de datos continuas climáticas de WordClim. Como resultado se observó una reducción en la superficie de los tipos térmicos mesocriófilo, hipercriófilo y criófilo, entre el Último Máximo Glaciar y la actualidad y aparece el termófilo en el escenario futuro. Esta investigación es una aportación para la comprensión de la distribución de la vegetación a escala nacional y su dinámica.
When More Is Less: Explaining the Curse of Too Much Capital for Early-Stage Ventures
Authors: Murray Alex , Fisher Greg
Published: February 2022

This study examines how the mechanisms that entrepreneurs use to successfully mobilize financial resources influence the long-term viability of their ventures. Through an inductive analysis of crowdfunded consumer drone ventures, we empirically illustrate and theoretically conceptualize the link between the claims entrepreneurs use to mobilize resources and the actions entrepreneurs must then take to develop successful ventures. We induct a theoretical framework to suggest that unbounded claims drive up the financial resources that ventures mobilize but reduce the likelihood of their long-term viability because of unmanageable technological complexity and uncontrolled organizational scaling, whereas bounded claims limit the financial resources that ventures mobilize but increase the likelihood of their long-term viability because of manageable technological complexity and controlled organizational scaling. We contribute to the resource mobilization literature by expounding on how the mechanisms that entrepreneurs use to mobilize financial resources are critical for ventures’ long-term viability over and above the amount of resources they mobilize. We contribute to the cultural entrepreneurship literature by linking research on claim making to the actions entrepreneurs must then take to deliver on their claims. Finally, we contribute to the literature on crowdfunding by connecting entrepreneurs’ campaign actions to the postcampaign outcome of on-time and on-scope product delivery.
Fabrication of Monetite by a Controlled Phase Transformation of Three Dimensionally Printed Calcium Sulfate Construct
Authors:   Biofunctional materials and devices research group, National Metal and Materials Technology Center (MTEC), 114 Paholyothin Road, Klong 1, Klongluang, Pathumthani, 12120, Thailand, Srion Autcharaporn , Thammarakcharoen Faungchat ,   Biofunctional materials and devices research group, National Metal and Materials Technology Center (MTEC), 114 Paholyothin Road, Klong 1, Klongluang, Pathumthani, 12120, Thailand, Suwanprateeb Jintamai ,   Biofunctional materials and devices research group, National Metal and Materials Technology Center (MTEC), 114 Paholyothin Road, Klong 1, Klongluang, Pathumthani, 12120, Thailand
Published: February 2022

M onetite is one of the calcium phosphates that has been used for bone regeneration and repair. Comparing to the widely used hydroxyapatite, monetite displayed greater resorption at physiological pH and could induce osteoclast resorption. Fabrication of a shape-customizable monetite construct by using a powder-based three dimensional printing (3DP) technique in combination with a phase transformation at low temperature was studied. Phase transformation of 3D printed calcium sulfate-based sample was carried out in 1M disodium hydrogen phosphate solution at pH5. Various processing parameters were then varied including temperatures (37 oC, 65 oC and 100 oC), sample weight to solution volume ratios (1:20, 1:30, 1:40 and 1:50) and soaking periods (24 h, 48 h, 72 h, 96 h and 120 h). It was found that a temperature of 100 oC, a sample weight to volume ratio of 1:50 and a time greater than 48 h were needed to fully transform the as-printed sample to monophasic monetite without causing the destruction of the structure or the incomplete transformation. Consistently, the microstructure of samples changed from rod-like crystals of calcium sulfate to petal-like crystals of monetite during the transformation process. Density, compressive modulus and strength decreased with soaking times during the course of transformation, but they did not further change with times after complete transformation. In vitro resorbability showed that 3D printed resorbed without conversion to other phase and its weight loss and ions release were greater than those of 3D printed hydroxyapatite indicating its greater resorption potential.
Preliminary Characterization of Mucus Crude Extracts from Mushroom Phallus indusiatus
Authors:   School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand, Saejung Thanyarat , Nitsawang Sarote ,   School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand, Punyamoonwongsa Patchara ,   School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
Published: February 2022

Skin diseases, such as dermatitis, allergies and eczema, are one of the most leading causes of global diseases, affecting millions of people worldwide. Most of them are associated with the skin dehydration condition, caused by the loss of natural moisturizing factors (NMFs) in the corneocyte skin layer. To resolve this issue, the exogenously administered hyaluronic acid (HA) therapeutics were introduced. Nonetheless, HA sources from microbial fermentation is still expensive with potential toxicity from the toxin protein impurities. We demonstrated an alternative NMFs source from the mucus extracts of the Phallus indusiatus ( P. indusiatus) mushroom. For this, the fresh mucus was partially purifi ed by the sequential chelation (CaCl2/EDTA). A combined use of both IR and 13C-NMR spectroscopic techniques confi rmed the presence of glucuronic acid (GlcA) in the crude extracts, as convinced by the presence of the IR absorption bands at 1600-1603 cm−1 (C=O stretching), 3000-3800 cm−1 (-OH stretching), and at 1402-1410 cm−1 (C-O stretching), together with the 13C-NMR resonances at 101 ppm, 79 ppm and 81 ppm. The disappearance of the NMR characteristic peaks, corresponding to the N-acetyl glucosamine (GlcNAc) at 1.9-2.0 ppm (1H-NMR) and 23-25 ppm (13C-NMR), suggested the extremely low level of the HA in the crude extracts. Nonetheless, these crude extracts showed the higher water content, comparing to the HA standard, highlighting their potential use as an alternative NMFs sources for dry skin therapeutics.
As Ações do Poder Público Municipal e a Configuração do Comércio Popular
Authors: Rios da Silva Vinícius
Published: February 2022

Durante o período de construção do referencial teórico, a partir do levantamento bibliográfico, foi possível perceber como a história de Feira de Santana se aproxima das feiras livres, ao ponto da cidade emergir da feira.
Observing Inclusion in STEM Classes: Academic and Social Participation of Students With and Without Intellectual and Developmental Disabilities
Authors: Kuntz Emily M. , Carter Erik W. , Cassady Kaitlyn , Knight Victoria F.
Published: February 2022

Calls to support inclusive educational experiences for students with intellectual and developmental disabilities (IDD) have been longstanding. General education STEM classes may provide a rich context for promoting the inclusion of these students within a relevant curricular area. To assess inclusive class participation, we directly observed 15 secondary students with IDD—along with a comparison group of their classmates without disabilities—in STEM-related classes. We focused on academic, social, and contextual measures. Although some similarities were found in the academic and social participation of students and their classmates, key differences were observed in the areas of what they learned, who they conversed with, and how they learned. We present recommendations for future research and practice aimed at strengthening inclusive educational experiences.
Set of all possible stigmatic pairs of mirrors
Authors: González-Acuña Rafael G.
Published: February 2022

Here, closed-form equations that express a pair of mirrors such that it forms a stigmatic optical system are presented. The mentioned equations are general enough to express the set of all possible pairs of stigmatic mirrors. Several examples for pairs of stigmatic mirrors are given and numerically tested with ray tracing, showing that their optical performance is, as expected, free of spherical aberration. Finally, the limitations and potential applications of stigmatic pairs are discussed.
Automatic evaluation of graft orientation during Descemet membrane endothelial keratoplasty using intraoperative OCT
Authors: Muijzer Marc B. , Heslinga Friso G. , Couwenberg Floor , Noordmans Herke-Jan , Oahalou Abdelkarim , Pluim Josien P. W. , Veta Mitko , Wisse Robert P. L.
Published: February 2022

Correct Descemet Membrane Endothelial Keratoplasty (DMEK) graft orientation is imperative for success of DMEK surgery, but intraoperative evaluation can be challenging. We present a method for automatic evaluation of the graft orientation in intraoperative optical coherence tomography (iOCT), exploiting the natural rolling behavior of the graft. The method encompasses a deep learning model for graft segmentation, post-processing to obtain a smooth line representation, and curvature calculations to determine graft orientation. For an independent test set of 100 iOCT-frames, the automatic method correctly identified graft orientation in 78 frames and obtained an area under the receiver operating characteristic curve (AUC) of 0.84. When we replaced the automatic segmentation with the manual masks, the AUC increased to 0.92, corresponding to an accuracy of 86%. In comparison, two corneal specialists correctly identified graft orientation in 90% and 91% of the iOCT-frames.
Feasibility of the soft attention-based models for automatic segmentation of OCT kidney images
Authors: Moradi Mousa , Du Xian , Huan Tianxiao , Chen Yu
Published: February 2022

Clinically, optical coherence tomography (OCT) has been utilized to obtain the images of the kidney’s proximal convoluted tubules (PCTs), which can be used to quantify the morphometric parameters such as tubular density and diameter. Such parameters are useful for evaluating the status of the donor kidney for transplant. Quantifying PCTs from OCT images by human readers is a time-consuming and tedious process. Despite the fact that conventional deep learning models such as conventional neural networks (CNNs) have achieved great success in the automatic segmentation of kidney OCT images, gaps remain regarding the segmentation accuracy and reliability. Attention-based deep learning model has benefits over regular CNNs as it is intended to focus on the relevant part of the image and extract features for those regions. This paper aims at developing an Attention-based UNET model for automatic image analysis, pattern recognition, and segmentation of kidney OCT images. We evaluated five methods including the Residual-Attention-UNET, Attention-UNET, standard UNET, Residual UNET, and fully convolutional neural network using 14403 OCT images from 169 transplant kidneys for training and testing. Our results show that Residual-Attention-UNET outperformed the other four methods in segmentation by showing the highest values of all the six metrics including dice score (0.81 ± 0.01), intersection over union (IOU, 0.83 ± 0.02), specificity (0.84 ± 0.02), recall (0.82 ± 0.03), precision (0.81 ± 0.01), and accuracy (0.98 ± 0.08). Our results also show that the performance of the Residual-Attention-UNET is equivalent to the human manual segmentation (dice score = 0.84 ± 0.05). Residual-Attention-UNET and Attention-UNET also demonstrated good performance when trained on a small dataset (3456 images) whereas the performance of the other three methods dropped dramatically. In conclusion, our results suggested that the soft Attention-based models and specifically Residual-Attention-UNET are powerful and reliable methods for tubule lumen identification and segmentation and can help clinical evaluation of transplant kidney viability as fast and accurate as possible.
Label-free detection of breast cancer cells using a functionalized tilted fiber grating
Authors: Chen Xiaoyong , Xu Pin , Lin Wenwei , Jiang Jin , Qu Hang , Hu Xuehao , Sun Jinghua , Cui Yukun
Published: February 2022

The detection of circulating tumor cells (CTCs) still faces a huge challenge partially because of low abundance of CTCs (1-10 cells/mL). In this work, a plasmonic titled fiber Bragg grating biosensor is proposed for detection of breast cancer cells. The biosensor is made by an 18° TFBG with a 50 nm-thick gold nanofilm coating over the surface of the fiber, further immobilized with a specific antibody against GPR30, which is a membrane receptor expressed in many breast cancers, serving as bait. In vitro tests have confirmed that the proposed biosensor can detect breast cancer cells in concentration of 5 cells/mL within 20 minutes and has good linearity in the range of 5–1000 cells/mL, which has met the requirement of CTC detection in real conditions. Furthermore, theoretical analysis based on the experimental results shows that the limit of detection can even reach single-cell level. Our proposed biosensor has a simple structure, is easy to manufacture, is of small size, and has a good performance, making it a good choice for real-time, label-free, and milliliter-volume detection of cancer cells in future.
Efficient coupling between single mode fibers and glass chip waveguides via graded refractive index fiber tips
Authors: Hwang Yongsop , Phillips Nicholas , Otten Dale E. , Riesen Nicolas , Lancaster David G.
Published: February 2022

Coupling characteristics between a single mode fiber (SMF) and a waveguide embedded in a glass chip via a graded index fiber (GIF) tip are investigated at a wavelength of 976 nm. The GIF tips comprise a coreless fiber section and a GIF section. A depressed cladding waveguide in a ZBLAN glass chip with a core diameter of 35 μm is coupled with GIF tips that have a range of coreless fiber and GIF lengths. An experimental coupling efficiency as high as 88% is obtained while a numerical simulation predicts 92.9% for the same GIF tip configuration. Since it is measured in the presence of Fresnel reflection, it can be further improved by anti-reflection coating. Additionally, it is demonstrated that a gap can be introduced between the chip waveguide and the GIF tip while maintaining the high coupling efficiency, thus allowing a thin planar optical component to be inserted. The results presented here will enable miniaturization and simplification of photonic chips with integrated waveguides by replacing bulk coupling lenses with integrated optical fibers.
Correction of a digital micromirror device lithography system for fabrication of a pixelated liquid crystal micropolarizer array
Authors: Liu Chang , Zhang Shiyuan , Liu Yuqing , Lu Meiying , Cao Wenhui , Huang Long , Zhang Han , Lu Zifeng , Mu Quanquan , Liu Hua
Published: February 2022

The combination of a digital micromirror device (DMD) lithography system and a rotatable polarizer provides a simple and convenient method to achieve the pixelated liquid crystal micropolarizer (LCMP) array for polarization imaging. In this paper, two crucial problems restricting the high-precision fabrication of LCMP array are pointed out and settled: the dislocation of LCMP pixels caused by parallelism error of the rotating polarizer and the grid defect caused by the gap between micromirrors. After correction, the maximum deviation of the fabricated LCMP pixels was reduced from 3.23 µm to 0.11 µm and the grid defect is eliminated. The correction method reported here lays a good foundation for the fine processing of liquid crystal devices with arbitrary photoalignment structure by using the DMD system.
Twin-nanofiber structure for a highly efficient single-photon collection
Authors: Shao Luqing , Wu Hao , Fang Wei , Tong Limin
Published: February 2022

Optical nanofiber-based single-photon source has attracted considerable interest due to its property of seamless integration with a single-mode fiber. With nanostructure engraved in the nanofiber, the single-photon collection efficiency can be greatly boosted with enhanced interaction between the single quantum emitter and the guided light. However, the prerequisite nanofabrication processes introduce complexities and extra loss. Here, we demonstrate that by simply placing a quantum emitter in the gap of two parallel nanofibers, single-photon coupling efficiency may reach 54.2%. Our numerical simulation results indicate that photon coupling efficiency of such simple structure is insensitive to the discrepancy in nanofiber radii, which further reduces the difficulties in device fabrication.
Precoded and pre-equalized multi-band FBMC transmission enabled by radio-frequency DACs and the undersampling technique
Authors: Chen Ming , Wang Dengqiao , Deng Aitao , Cai Yuxin , Chen Qinghui
Published: February 2022

In this Letter, we use radio-frequency digital-to-analog converters (DACs) operating in different frequency response modes to generate a high spectral-efficiency multi-band (MB) filter bank multicarrier (FBMC) signal. In the receiver, the undersampling technique is employed to realize down-conversions. No electrical mixers are required. Besides, discrete Fourier transform and orthogonal circulant matrix transform precoding techniques combined with channel-independent digital pre-equalization are enabled to enhance transmission performance. Both numerical simulations and offline experiments are performed. The relevant results show that the MB-FBMC without a cyclic prefix (CP) is robust against inter-symbol interference induced by the band-pass filtering. By using precoding and pre-equalization techniques, the bit error rate can be improved by more than one order of magnitude. In contrast, an additional 12.5% CP overhead is required for the MB orthogonal frequency division multiplexing system to achieve such an improvement.
On z-coherence in self-focusing
Authors: Gori F. , Martínez-Herrero R. , Piquero G. , de Sande J. C. G. , Korotkova O. , Santarsiero M.
Published: February 2022

Both the intensity distribution and the degree of coherence between pairs of points along the propagation axis (z-coherence) are derived in closed form for a phenomenon of self-focusing produced by circularly coherent light. The first confirms results previously obtained numerically, while the second exhibits new complex features. The physical interpretation is obtained by a suitable pseudo-modal expansion that suggests an analogy with a simple two-mode structure.
Helical plasma filaments from the self-channeling of intense femtosecond laser pulses in optical fibers: publisher’s note
Authors: Mangini F. , Ferraro M. , Zitelli M. , Niang A. , Mansuryan T. , Tonello A. , Couderc V. , De Luca A. , Babin S. A. , Frezza F. , Wabnitz S.
Published: February 2022

This publisher’s note contains a correction to Opt. Lett. 47, 1 (2022)10.1364/OL.445321.
Laser assisted surface conditioning of a residual pattern on single crystal silicon induced by ultra-precision cutting
Authors: Xiao Junfeng , Huang Weiqi , Li Tao , Wu Yanling , Chen Xiao , Zhang Jianguo , Xu Jianfeng
Published: February 2022

Fabrication of a silicon lens using an ultra-precision machining tool generates a periodic cutting texture, which can cause light diffraction and scattering, resulting in a significant degradation of the optical performance. This phenomenon usually appears in the form of rainbow patterns. In this study, a single-crystal silicon wafer, after diamond turning, is polished by a nanosecond laser mounted on a four-axis ultra-precision machine lathe. It’s found that the rainbow pattern has been effectively eliminated after laser irradiation through the observation of surface topography. Effects of defocus, scanning velocity, and pitch on polishing were investigated. This polishing method is able to obtain surface roughness Sa better than 1 nm for silicon surface without removing or adding material to the workpiece, and high throughout can be achieved through easy integration with the existing cutting process.
Gigawatt-class, tabletop, isolated-attosecond-pulse light source
Authors: Xue Bing , Midorikawa Katsumi , Takahashi Eiji J.
Published: February 2022

Powerful and stable attosecond pulse sources have the potential for wide application in ultrafast science. For this purpose, we have produced a soft X-ray supercontinuum with a pulse energy of 0.24 µJ using high-order harmonics from a multi-terawatt, 10 Hz, three-channel waveform synthesizer [Sci. Adv. 6, eaay2802 (2020)STAMCV1468-699610.1126/sciadv.aay2802]. Here, we report an attosecond streaking scheme that is designed to measure this isolated attosecond pulse at a low-repetition rate. We retrieved a pulse duration of 226 attoseconds (as), demonstrating the realization of 1.1 gigawatt isolated as pulses on a tabletop, which compares favorably to an X-ray free-electron laser in a large facility.
Gene-rich germline-restricted chromosomes in black-winged fungus gnats evolved through hybridization
Authors: Hodson Christina N. , Jaron Kamil S. , Gerbi Susan , Ross Laura
Published: February 2022

Germline-restricted DNA has evolved in diverse animal taxa and is found in several vertebrate clades, nematodes, and flies. In these lineages, either portions of chromosomes or entire chromosomes are eliminated from somatic cells early in development, restricting portions of the genome to the germline. Little is known about why germline-restricted DNA has evolved, especially in flies, in which 3 diverse families, Chironomidae, Cecidomyiidae, and Sciaridae, carry germline-restricted chromosomes (GRCs). We conducted a genomic analysis of GRCs in the fungus gnatBradysia(Sciara)coprophila(Diptera: Sciaridae), which has 2 large germline-restricted “L” chromosomes. We sequenced and assembled the genome ofB.coprophilaand used differences in sequence coverage and k-mer frequency between somatic and germline tissues to identify GRC sequence and compare it to the other chromosomes in the genome. We found that the GRCs inB.coprophilaare large, gene rich, and have many genes with divergent homologs on other chromosomes in the genome. We also found that 2 divergent GRCs exist in the population we sequenced. GRC genes are more similar in sequence to genes from another Dipteran family (Cecidomyiidae) than to homologous genes from Sciaridae. This unexpected finding suggests that these chromosomes likely arose in Sciaridae through hybridization with a related lineage. These results provide a foundation from which to answer many questions about the evolution of GRCs in Sciaridae, such as how this hybridization event resulted in GRCs and what features on these chromosomes cause them to be restricted to the germline.
Bacterial age distribution in soil – Generational gaps in adjacent hot and cold spots
Authors: Borer Benedict , Or Dani
Published: February 2022

Resource patchiness and aqueous phase fragmentation in soil may induce large differences local growth conditions at submillimeter scales. These are translated to vast differences in bacterial age from cells dividing every thirty minutes in close proximity to plant roots to very old cells experiencing negligible growth in adjacent nutrient poor patches. In this study, we link bacterial population demographics with localized soil and hydration conditions to predict emerging generation time distributions and estimate mean bacterial cell ages using mechanistic and heuristic models of bacterial life in soil. Results show heavy-tailed distributions of generation times that resemble a power law for certain conditions, suggesting that we may find bacterial cells of vastly different ages living side by side within small soil volumes. Our results imply that individual bacteria may exist concurrently with all of their ancestors, resulting in an archive of bacterial cells with traits that have been gained (and lost) throughout time–a feature unique to microbial life. This reservoir of bacterial strains and the potential for the reemergence of rare strains with specific functions may be critical for ecosystem stability and function.
Acute exposure to sublethal doses of neonicotinoid insecticides increases heat tolerance in honey bees
Authors: Gonzalez Victor H. , Hranitz John M. , McGonigle Mercedes B. , Manweiler Rachel E. , Smith Deborah R. , Barthell John F.
Published: February 2022

The European honey bee, Apis mellifera L., is the single most valuable managed pollinator in the world. Poor colony health or unusually high colony losses of managed honey bees result from a myriad of stressors, which are more harmful in combination. Climate change is expected to accentuate the effects of these stressors, but the physiological and behavioral responses of honey bees to elevated temperatures while under simultaneous influence of one or more stressors remain largely unknown. Here we test the hypothesis that exposure to acute, sublethal doses of neonicotinoid insecticides reduce thermal tolerance in honey bees. We administered to bees oral doses of imidacloprid and acetamiprid at 1/5, 1/20, and 1/100 of LD50 and measured their heat tolerance 4 h post-feeding, using both dynamic and static protocols. Contrary to our expectations, acute exposure to sublethal doses of both insecticides resulted in higher thermal tolerance and greater survival rates of bees. Bees that ingested the higher doses of insecticides displayed a critical thermal maximum from 2 ˚C to 5 ˚C greater than that of the control group, and 67%–87% reduction in mortality. Our study suggests a resilience of honey bees to high temperatures when other stressors are present, which is consistent with studies in other insects. We discuss the implications of these results and hypothesize that this compensatory effect is likely due to induction of heat shock proteins by the insecticides, which provides temporary protection from elevated temperatures.
Host-symbiont stress response to lack-of-sulfide in the giant ciliate mutualism
Authors: Espada-Hinojosa Salvador , Drexel Judith , Kesting Julia , Kniha Edwin , Pifeas Iason , Schuster Lukas , Volland Jean-Marie , Zambalos Helena C. , Bright Monika
Published: February 2022

The mutualism between the thioautotrophic bacterial ectosymbiontCandidatusThiobius zoothamnicola and the giant ciliateZoothamnium niveumthrives in a variety of shallow-water marine environments with highly fluctuating sulfide emissions. To persist over time, both partners must reproduce and ensure the transmission of symbionts before the sulfide stops, which enables carbon fixation of the symbiont and nourishment of the host. We experimentally investigated the response of this mutualism to depletion of sulfide. We found that colonies released some initially present but also newly produced macrozooids until death, but in fewer numbers than when exposed to sulfide. The symbionts on the colonies proliferated less without sulfide, and became larger and more rod-shaped than symbionts from freshly collected colonies that were exposed to sulfide and oxygen. The symbiotic monolayer was severely disturbed by growth of other microbes and loss of symbionts. We conclude that the response of both partners to the termination of sulfide emission was remarkably quick. The development and the release of swarmers continued until host died and thus this behavior contributed to the continuation of the association.
Interventions to increase early infant diagnosis of HIV infection: A systematic review and meta-analysis
Authors: Okusanya Babasola , Kimaru Linda J. , Mantina Namoonga , Gerald Lynn B. , Pettygrove Sydney , Taren Douglas , Ehiri John
Published: February 2022

Objectives

Early infant diagnosis (EID) of HIV infection increases antiretroviral therapy initiation, which reduces pediatric HIV-related morbidity and mortality. This review aims to critically appraise the effects of interventions to increase uptake of early infant diagnosis.

Design

This is a systematic review and meta-analysis of interventions to increase the EID of HIV infection. We searched PubMed, EMBASE, CINAHL, and PsycINFO to identify eligible studies from inception of these databases to June 18, 2020. EID Uptake at 4–8 weeks of age was primary outcome assessed by the review. We conducted meta-analysis, using data from reports of included studies. The measure of the effect of dichotomous data was odds ratios (OR), with a 95% confidence interval. The grading of recommendations assessment, development, and evaluation (GRADE) approach was used to assess quality of evidence.

Settings

The review was not limited by time of publication or setting in which the studies conducted.

Participants

HIV-exposed infants were participants.

Results

Database search and review of reference lists yielded 923 unique titles, out of which 16 studies involving 13,822 HIV exposed infants (HEI) were eligible for inclusion in the review. Included studies were published between 2014 and 2019 from Kenya, Nigeria, Uganda, South Africa, Zambia, and India. Of the 16 included studies, nine (experimental) and seven (observational) studies included had low to moderate risk of bias. The studies evaluated eHealth services (n = 6), service improvement (n = 4), service integration (n = 2), behavioral interventions (n = 3), and male partner involvement (n = 1). Overall, there was no evidence that any of the evaluated interventions, including eHealth, health systems improvements, integration of EID, conditional cash transfer, mother-to-mother support, or partner (male) involvement, was effective in increasing uptake of EID at 4–8 weeks of age. There was also no evidence that any intervention was effective in increasing HIV-infected infants’ identification at 4–8 weeks of age.

Conclusions

There is limited evidence to support the hypothesis that interventions implemented to increase uptake of EID were effective at 4–8 weeks of life. Further research is required to identify effective interventions that increase early infant diagnosis of HIV at 4–8 weeks of age.

Prospero number

(CRD42020191738).
Transcriptional signatures of clonally derived Toxoplasma tachyzoites reveal novel insights into the expression of a family of surface proteins
Authors: Theisen Terence C. , Boothroyd John C.
Published: February 2022

Toxoplasma gondiihas numerous, large, paralogous gene families that are likely critical for supporting its unparalleled host range: nearly any nucleated cell in almost any warm-blooded animal. TheSRS(SAG1-related sequence) gene family encodes over 100 proteins, the most abundant of which are thought to be involved in parasite attachment and, based on their stage-specific expression, evading the host immune response. For most SRS proteins, however, little is understood about their function and expression profile. Single-parasite RNA-sequencing previously demonstrated that across an entire population of lab-grown tachyzoites, transcripts for over 70SRSgenes were detected in at least one parasite. In any one parasite, however, transcripts for an average of only 7SRSgenes were detected, two of which,SAG1andSAG2A, were extremely abundant and detected in virtually all. These data do not address whether this pattern of sporadicSRSgene expression is consistently inherited among the progeny of a given parasite or arises independently of lineage. We hypothesized that ifSRSexpression signatures are stably inherited by progeny, subclones isolated from a cloned parent would be more alike in their expression signatures than they are to the offspring of another clone. In this report, we compare transcriptomes of clonally derived parasites to determine the degree to which expression of the SRS family is stably inherited in individual parasites. Our data indicate that in RH tachyzoites,SRSgenes are variably expressed even between parasite samples subcloned from the same parent within approximately 10 parasite divisions (72 hours). This suggests that the pattern of sporadically expressedSRSgenes is highly variable and not driven by inheritance mechanisms, at least under our conditions.
Cities as complex systems—Collection overview
Authors: Rybski Diego , González Marta C.
Published: February 2022

This collection provides a contemporary excerpt of “Cities as complex systems”. The contributions have been submitted between April and October 2020. We briefly discuss example papers addressing the themes “urban scaling”, “urban mobility”, “flows in cities”, “spatial analysis”, “information technology and cities”, and “cities in time”. After motivating the intersection of cities and complexity, we provide an introduction and additional thoughts on urban scaling.
Accessible, fast and easy fabrication of hydrophilic-in-hydrophobic microdroplet arrays
Authors: Toppi Arianna , Dufva Martin
Published: February 2022

Microdroplet arrays (MDAs) are powerful tools for digital immunoassays, high-throughput screening and single cell analysis. However, MDAs are usually produced with cleanroom processes, which are associated with high costs and low availability. Furthermore, in order to obtain robust and stable MDAs based on hydrophilic spots surrounded by a hydrophobic background, the chemistry must be strictly controlled, which is challenging using shared equipment. Here, we developed a new method to fabricate MDA substrates independently from the cleanroom. A small and low-cost in-house built system to collimate the light source was assembled for photopatterning a negative resist, and spots with diameters down to 4 μm were obtained, with only 3% to 5% spot-to-spot variation across the same sample and high batch-to-batch reproducibility. The use of a negative photoresist enabled the formation of a hydrophobic coating in solution which yielded high-quality MDAs. The feasibility for carrying out digital assays was demonstrated by measuring anti-Tau antibody in sample buffers containing bovine serum albumin, with no noticeable surface fouling. The reported, robust, cost-effective, and fast process could hence lower the threshold to fabricate and use MDAs for digital immunoassays and other microcompartmentalization-based applications.