bluuebunny/crossref_metadata_2025 huggingface dataset:
Maternal Hypothyroidism in Rats Reduces Placental Lactogen, Lowers Insulin Levels, and Causes Glucose Intolerance
Authors: Kent Nykola Louise , Atluri Sharat Chandra , Cuffe James Sebastian Martin
Published: November 2021

Hypothyroidism increases the incidence of gestational diabetes mellitus (GDM) but the mechanisms responsible are unknown. This study aimed to assess the pathophysiological mechanisms by which hypothyroidism leads to glucose intolerance in pregnancy. Hypothyroidism was induced in female Sprague-Dawley rats by adding methimazole (MMI) to drinking water at moderate (MOD, MMI at 0.005% w/v) and severe (SEV, MMI at 0.02% w/v) doses from 1 week before pregnancy and throughout gestation. A nonpregnant cohort received the same dose for the same duration but were not mated. On gestational day 16 (GD16), or nonpregnant day 16 (NP16), animals were subjected to an intraperitoneal glucose tolerance test. Tissues and blood samples were collected 4 days later. Hypothyroidism induced a diabetic-like phenotype by GD16 in pregnant females only. Pregnant MOD and SEV females had reduced fasting plasma insulin, less insulin following a glucose load, and altered expression of genes involved in insulin signaling within skeletal muscle and adipose tissue. Hypothyroidism reduced rat placental lactogen concentrations, which was accompanied by reduced percentage β-cell cross-sectional area (CSA) relative to total pancreas CSA, and a reduced number of large β-cell clusters in the SEV hypothyroid group. Plasma triglycerides and free fatty acids were reduced by hypothyroidism in pregnant rats, as was the expression of genes that regulate lipid homeostasis. Hypothyroidism in pregnant rats results in a diabetic-like phenotype that is likely mediated by impaired β-cell expansion in pregnancy. This pregnancy-specific phenomenon is likely due to reduced placental lactogen secretion.
Podocyte Bioenergetics in the Development of Diabetic Nephropathy: The Role of Mitochondria
Authors: Audzeyenka Irena , Bierżyńska Agnieszka , Lay Abigail C
Published: November 2021

Diabetic nephropathy (DN) is the leading cause of kidney failure, with an increasing incidence worldwide. Mitochondrial dysfunction is known to occur in DN and has been implicated in the underlying pathogenesis of disease. These complex organelles have an array of important cellular functions and involvement in signaling pathways, and understanding the intricacies of these responses in health, as well as how they are damaged in disease, is likely to highlight novel therapeutic avenues. A key cell type damaged early in DN is the podocyte, and increasing studies have focused on investigating the role of mitochondria in podocyte injury. This review will summarize what is known about podocyte mitochondrial dynamics in DN, with a particular focus on bioenergetic pathways, highlighting key studies in this field and potential opportunities to target, enhance or protect podocyte mitochondrial function in the treatment of DN.
CFAP61 is required for sperm flagellum formation and male fertility in human and mouse
Authors: Liu Siyu , Zhang Jintao , Kherraf Zine Eddine , Sun Shuya , Zhang Xin , Cazin Caroline , Coutton Charles , Zouari Raoudha , Zhao Shuqin , Hu Fan , Fourati Ben Mustapha Selima , Arnoult Christophe , Ray Pierre F. , Liu Mingxi
Published: November 2021

Defects in the structure or motility of cilia and flagella may lead to severe diseases such as primary ciliary dyskinesia (PCD), a multisystemic disorder with heterogeneous manifestations affecting primarily respiratory and reproductive functions. We report that CFAP61 is a conserved component of the calmodulin- and radial spoke-associated complex (CSC) of cilia. We find that a CFAP61 splice variant, c.143+5G>A, causes exon skipping/intron retention in human, inducing a multiple morphological abnormalities of the flagella (MMAF) phenotype. We generated Cfap61 knockout mice that recapitulate the infertility phenotype of the human CFAP61 mutation, but without other symptoms usually observed in PCD. We find that CFAP61 interacts with the CSC, radial spoke stalk and head. During early stages of Cfap61−/− spermatid development, the assembly of radial spoke components is impaired. As spermiogenesis progresses, the axoneme in Cfap61−/− cells becomes unstable and scatters, and the distribution of intraflagellar transport proteins is disrupted. This study reveals an organ-specific mechanism of axoneme stabilization that is related to male infertility.
DUSP6 regulates radiosensitivity in glioblastoma by modulating the recruitment of phosphorylated DNAPKcs at DNA double-strand breaks
Authors: Nair Jyothi , Basha Syed Safiulla , Mahaddalkar Tejashree , Ketkar Madhura , Thorat Rahul , Sastri Goda Jayant , Dutt Shilpee
Published: November 2021

Glioblastoma (GBM) has poor median survival due to its resistance to chemoradiotherapy, which results in tumor recurrence. Recurrent GBMs currently lack effective treatments. DUSP6 is known to be pro-tumorigenic and is upregulated in GBM. We show that DUSP6 expression is significantly higher in recurrent GBM patient biopsies compared to expression levels in primary GBM biopsies. Importantly, although it has been reported to be a cytoplasmic protein, we found nuclear localization of DUSP6 in primary and recurrent patient samples and in parent and relapse populations of GBM cell lines generated from an in vitro radiation survival model. DUSP6 inhibition using BCI resulted in decreased proliferation and clonogenic survival of parent and relapse cells. Pharmacological or genetic inhibition of DUSP6 catalytic activity radiosensitized primary and, importantly, relapse GBM cells by inhibiting the recruitment of phosphorylated DNAPKcs (also known as PRKDC), subsequently downregulating the recruitment of phosphorylated histone H2AX (γH2AX) and 53BP1 (also known as TP53BP1). This resulted in decreased cell survival and prolonged growth arrest upon irradiation in vitro and significantly increased the progression-free survival in orthotopic mouse models of GBM. Our study highlights a non-canonical function of DUSP6, emphasizing the potential application of DUSP6 inhibitors in the treatment of recurrent GBM.
Lateral versus posterior surgical approach for the treatment of supracondylar humeral fractures in children: a systematic review and meta-analysis
Authors: Irianto Komang Agung , Pradana I Putu Gede Pradnyadewa , De Vega Brigita
Published: November 2021

Background: Supracondylar humeral fracture (SHF) is the most common type of fracture in children. Moreover, lateral and posterior surgical approaches are the most frequently chosen approaches for open reduction surgery in displaced SHF when C-arm is unavailable. However, previous literature showed mixed findings regarding functional and cosmetic outcomes. Currently, no systematic review and meta-analysis has compared these two procedures. 

Methods: Our protocol was registered at PROSPERO (registration number CRD42021213763). We conducted a comprehensive electronic database search in MEDLINE, EMBASE, and CENTRAL. Two independent reviewers screened the title and abstract, followed by full-text reading and study selection based on eligibility criteria. The quality of the selected studies was analyzed with the ROBINS-I tool. Meta-analysis was carried out to compare the range of motion (functional outcome) and cosmetic outcome according to Flynn’s criteria. This systematic review was conducted based on PRISMA and Cochrane handbook guidelines. 

Results: Our initial search yielded 163 studies, from which we included five comparative studies comprising 231 children in the qualitative and quantitative analysis. The lateral approach was more likely to result in excellent (OR 1.69, 95% CI [0.97-2.93]) and good (OR 1.12, 95% CI [0.61-2.04]) functional outcomes and less likely to result in fair (OR 0.84, 95% CI [0.34-2.13]) and poor (OR 0.42, 95% CI [0.1-1.73]) functional outcomes compared to the posterior approach. In terms of cosmetic results, both approaches showed mixed findings. The lateral approach was more likely to result in excellent (OR 1.11, 95% CI [0.61-2.02]) and fair (OR 1.18, 95% CI [0.49-2.80]) but less likely to result in good (OR 0.79, 95% CI [0.40-1.55]) cosmetic outcomes. However, none of these analyses were statistically significant (p> 0.05). 

Conclusion: Lateral and posterior surgical approaches resulted in satisfactory functional and cosmetic outcomes. The two approaches are comparable for treating SHF in children when evaluated with Flynn’s criteria.
Smokeless tobacco use and reproductive outcomes among women: a systematic review
Authors: Radhika A.G. , B.  Neogi Sutapa , GS Preetha , Swain Sumant , Kaur Jaswinder , Kaur Jagdish
Published: November 2021

Background: Both smoked and smokeless tobacco use have deleterious effects on most major organ systems including the

reproductive system. We conducted a systematic review on smokeless tobacco (SLT) use and

reproductive outcomes among women.

Methods: We searched Pubmed, ProQuest, Cochrane, Wiley and Emerald databases for studies

involving smokeless tobacco use in women with any or a combination of three conditions:

infertility, menstrual disorders and pelvic inflammatory disease (PID). Eligibility criteria included

English language publications from 1st January 1990 - 31st October 2020. CADIMA software

used for filtering the studies and modified SIGN checklist for the quality assessment. The findings

are reported as per the PRISMA guidelines. The AXIS and ROBIN E tool were used for assessment of risk of bias.

Results: In total, three studies addressed our research question. Two studies addressed infertility

(prospective cohort: n=501, cross sectional: n=192) of which, the cross-sectional study compared

the mean cotinine levels between those with infertility, menstrual disorders and PID. This study

also explored the association between SLT and PID. PID was the most common gynecological

complaint. Women with PID had significantly higher urinary cotinine levels = 24.95±12.259) ng/

ml (p=0.0144). Mean urinary cotinine in women with menstrual complaints was 19.32±10.29 ng/ml. 

The other study used population-based sampling of 501 couples who attempted pregnancy (enrolled in the LIFE Study). 

Results showed that only 2% (n=28) of men and none of the women used smokeless tobacco. 

Compared with never users of tobacco, smoking by females was individually associated with longer time-to-pregnancy;

 smoking among males remained significant when modeling partners together.

Conclusions: Available studies exploring associations between SLT and reproductive outcomes

are inconclusive due to limitations in the study methodologies. More studies with robust study

designs are required from low- and middle-income countries with high prevalence of SLT use.
Equalities between the BLUEs and BLUPs under the partitioned linear fixed model and the corresponding mixed model
Authors: Haslett Stephen , Isotalo Jarkko , Puntanen Simo
Published: November 2021

In this article we consider the partitioned fixed linear model F : y = X1β1 + X2β2 + ε" and the corresponding mixed model M : y =X1β1+X2u+ ε, where ε is a random error vector and u is a random effect vector. In 2006, Isotalo, M¨ols, and Puntanen found conditions under which an arbitrary representation of the best linear unbiased estimator (BLUE) of an estimable parametric function of β1 in the fixed model F remains BLUE in the mixed model M . In this paper we extend the results concerning further equalities arising from models F and M.
Końska mięta (Mentha arvensis), kobyli szczaw (Rumex obtusifolius) i krowi mlecz (Taraxacum officinale)
Authors: Kielak Olga
Published: November 2021

Field Mint [Polish: “Horse Mint”] (Mentha arvensis), Curly Dock [Polish: “Mare Dock”] (Rumex obtusifolius) and Dandelion [Polish: “Cow Dandelion”] (Taraxacum officinale). On the Names of Farm Animals in Folk Phytonyms

The subject of the article are folk phytonyms with an animal component. While analyzing the “animal” names of plants in the cultural context, the author reaches for so-called “co-linguistic data” (i.e. folk knowledge, beliefs and practices) related to animals and plants. Also, she arranges the phytonyms according to the semantic criterion, distinguishing the names of plants motivated by: (1) the animal’s appearance and (2) the appearance of the animal’s body parts, (3) animals’ smells, (4) the use of a plant as animal food, (5) the way in which the plant is used in folk magic and (6) in folk veterinary medicine. The analysis of dialectal names of plants in the cultural context makes it possible to consider the status of the animal part of the name. On the basis of her analyses, the author proves that both in the case of complex plant names and noun derivatives, the animal part of the name becomes “independent” in terms of a meaning and adopts qualitative meanings such as “big, great”, “dedicated to an animal (as food or medicine)”, “worse, useless for a human being”.
Profit or Growth? Dynamic Order Allocation in a Hybrid Workforce
Authors: He Eryn Juan , Goh Joel
Published: November 2021

Modern digital technology has enabled the emergence of the hybrid workforce in service organizations, where a firm uses on-demand freelancers to augment its traditional labor supply of employees. Freelancers are typically supplied by an electronic platform. How should demand be allocated between employees and freelancers? Under what conditions is the system (comprising the firm and its platform) sustainable in the long run? We investigate these questions in the context of last-mile delivery. We develop a discrete-time, stochastic dynamic program that captures the system’s profit from serving demand and the platform’s growth dynamics. The dynamic model incorporates a service constraint for the platform and a simple version of a stochastic network effect. We find that the answers to our research questions critically depend on two key parameters: the mean and variance of the cross-network effect. We conduct a numerical study with data from a last-mile delivery firm in Vietnam to illustrate our findings.

This paper was accepted by Vishal Gaur, operations management.
O Congresso dos Estados Unidos e os impasses na aprovação do NAFTA | The Congress of the United States and the impasses in the approval of NAFTA
Authors: Mattos Angelo Raphael
Published: November 2021

A partir das competências constitucionais do Congresso dos Estados Unidos em política externa, das plataformas dos partidos Democrata e Republicano de 1992, bem como dos argumentos a favor e contra a implementação do North American Free Trade Agreement (NAFTA), o artigo objetiva compreender e discutir as razões da dificuldade enfrentada por Bill Clinton para aprovar o NAFTA no Congresso dos EUA em 1993. Os resultados das análises dos diferentes grupos domésticos, incluindo os atores Executivo e Legislativo, indicam que posições ideológicas, sobretudo presentes no Partido Democrata, como questões trabalhistas e ambientais, representaram o principal fator de resistência ao NAFTA no Capitólio.Palavras-chave: Congresso; Estados Unidos; NAFTA.ABSTRACTBased on the constitutional powers of the United States Congress in foreign policy, the platforms of the Democratic and Republican parties of 1992, as well as the arguments for and against the implementation of the North American Free Trade Agreement (NAFTA), the article aimed to understand and discuss the reasons for Bill Clinton's difficulty in passing NAFTA to the US Congress in 1993. The results of the analyzes of different domestic groups, including the Executive and Legislative actors, indicate that ideological positions, especially present in the Democratic Party, as labor and environmental issues, represented the main factor of resistance to NAFTA in the Capitol. Keywords: Congress; United States; NAFTA. Recebido em: 08 fev. 2021 | Aceito em: 20 set. 2021.
Culturas infantis e aprendizagens das crianças pequenas na pré-escola
Authors: Kremer Claines , Barbosa Maria Carmen Silveira
Published: November 2021

Este artigo é subsequente a uma pesquisa de Mestrado fundamentada em diálogos teóricos entre a Pedagogia da Infância e a Antropologia Interpretativa, que teve como objetivo compreender o ponto de vista de crianças pequenas acerca de suas aprendizagens na pré-escola. Metodologicamente, o estudo orientou-se nos pressupostos da Pesquisa com Crianças e da Etnografia. Para este artigo, os dados construídos no campo empírico foram organizados em duas unidades analíticas: a primeira com foco na relação entre brincadeira e aprendizagem, e a segunda com ênfase na apropriação que as crianças fazem sobre a escrita dos nomes. Os resultados sugerem que as culturas infantis são intimamente relacionadas às aprendizagens das crianças e conclui-se que elas devem ser consideradas na discussão de processos educativos na pré-escola.
Experiências de um sarau: o inédito viável em meio a pandemia
Authors: Rodrigues Penélope Alberto , Carrijo Viviane Letícia Silva , Modesto-Sarra Luciana Kool
Published: November 2021

Este artigo tem por objetivo discutir uma proposta de sarau virtual, realizado em junho de 2020, por meio da plataforma Zoom, pela Brincada do Brincar, uma das frentes do Projeto de extensão “Brincadas: o inédito viável em tempos de crise” (PUC SP). Problematiza-se o contexto de pandemia do período de realização do sarau, apresenta-se as motivações de realização do sarau virtual no âmbito do Projeto Brincadas. O sarau virtual é descrito e analisado por meio da seleção de arquivos digitais do acervo do projeto; é analisado com base nos estudos freireanos, principalmente, no conceito de “inédito viável” (FREIRE, 1970/1987), e no “brincar” de Vygotsky (1933/1991). O sarau, a partir da vivência de seus participantes, criou possibilidades para atos de esperança diante da crise mundial da saúde e do contexto de isolamento e distanciamento físico. Esse encontro poético fomentou a interação e a colaboração entre os envolvidos que puderam experienciar a criação de um novo modo de sentir, agir, viver, ser e estar no mundo.
Determination of Flexural Strength of Structural Red and White Oak and Hardwood Composite Lumber
Authors: Khademibami Laya , Sherrington Alan , Shmulsky Rubin , Quin Franklin
Published: November 2021

In this research, flexural properties of mill-run, in-grade red and white oak lumber from a single mill and commercially available laminated hardwood composite were evaluated. Structurally graded green (wet) freshly sawn red and white oak 5 by 10-cm (2 by 4-in) nominal lumber as well as glue-laminated hardwood composite billets were tested in bending and their modulus of rupture (MOR) and modulus of elasticity (MOE) properties were developed. It is well documented that MOR and MOE are two major indicators to evaluate flexural strength of wood lumbers. From these data, summary statistics, design values, and mean separations were calculated and reported. Overall, the red and white oak lumber performed similarly to structural No. 2 grade material. The hardwood composite billets were highly uniform. Each of the three materials demonstrated a reasonably good relationship between MOE and MOR, thereby suggesting that MOE could be used as a selection criterion for strength in a commercial use situation.
Fault identification for the catastrophic 1894 Atalanti earthquake using 3D finite-difference modelling and local geophysical data
Authors: Mouzakiotis Evangelos
Published: November 2021

An identification of the responsible faults for the destructive earthquakes of 1894 in the Atalanti region was carried out by employing a novel application of 3D finite-difference wavefield modeling. Several faults proposed in the literature were tested in detailed 3D simulations, by also utilizing a detailed local 3D velocity model, as well as the local topography. The assessment of the most probable sources for these events was based on the correlation of reported damages with the distribution of the simulated peak ground acceleration. Furthermore, the distribution of the spectral amplitudes at higher frequencies that are related to the resonant frequencies of the local buildings on that time period was also used as an indicator. The general effect of the local 3D subsurface structure on the propagation of the wavefield and the spatial distribution of the ground motion was also investigated. The Malessina fault was identified as a probable source for the main event of 20/4/1894 based on the results of the 3D modeling, whereas the 3D effect was found to be a highly contributing factor to the distribution of the simulated ground motion.
Solvent-Kaolinite Interactions Investigated using the 3D-Rism-Kh Molecular Theory of Solvation
Authors: Stoyanov Stanislav R. , Lin Feng , Xu Yuming
Published: November 2021

The oil sands of western Canada represent the third largest hydrocarbon deposit in the world. Bitumen, a very heavy petroleum, is recovered from mined oil sands using warm water extraction followed by separation treatments to isolate the bitumen product. The high energy, water use, as well as tailings remediation challenges associated with the warm water extraction process raise major environmental concerns. Non-aqueous extraction using organic solvents at room temperature has been investigated extensively as an alternative to the warm water extraction process. The main challenge to the large-scale implementation of non-aqueous extraction is the retention of solvent in the tailings. The objective of this work was to present and validate a computational model for the interaction of solvents used in non-aqueous extraction with minerals, such as the abundant and adsorbent clay mineral kaolinite. The model system contained a periodically extended kaolinite platelet immersed in a solvent and all were treated at the atomic level using the 3D Reference Interaction Site Model with the Kovalenko-Hirata closure approximation (3D-RISM-KH) molecular theory of solvation. The solvent solvation free energy of interaction with kaolinite as well as site-specific adsorption energies and kinetic barriers for desorption were computed based on the solvent site density distribution functions. Moreover, the lateral and integrated density distributions were computed to analyze the organization of solvent at kaolinite surfaces. The integrated density distribution profiles were correlated with experimental adsorption isotherms. The results showed very strong adsorption of ethanol and weak adsorption of hydrocarbon solvents on kaolinite, which were in qualitative agreement with experimental solvent extraction reports. The model and these findings are valuable in understanding the mechanism of solvent retention in tailings after non-aqueous extraction and highlight the action of hydroxylated cosolvent additives to enhance extraction using nonpolar solvents.
Sorption of Diclofenac from Aqueous Solution on an Organobentonite and Adsorption of Cadmium on Organobentonite Saturated with Diclofenac
Authors: Martinez-Costa Jesús Iván , Leyva-Ramos Roberto , Padilla-Ortega Erika
Published: November 2021

Toxic pollutants such as diclofenac (DCF) and cadmium(II) have been detected together in various water sources; these compounds have adverse effects on human health. The objective of the present study was to investigate the sorption of DCF and Cd(II) from aqueous solutions on an organobentonite. The organobentonite was synthesized by adsorbing the surfactant hexadecyltrimethylammonium (HDTMA) on bentonite; this was designated OBHDTMA. The sorption of DCF and Cd(II) on OBHDTMA and of Cd(II) on OBHDTMA saturated with DCF (OBHDTMA-DCF) were then studied. The bentonite, OBHDTMA, and OBHDTMA-DCF were characterized by X-ray diffraction, thermogravimetric analysis, and Fourier-transform infrared spectroscopy. The capacity of OBHDTMA for adsorbing DCF depended on the solution pH, ionic strength, and temperature. The effect of pH on the adsorption capacity of OBHDTMA was anomalous because, depending on the concentration of DCF at equilibrium, the adsorption capacity increased or decreased by raising the pH. The capacity of OBHDTMA was enhanced by increasing the temperature from 15 to 35°C and by reducing the ionic strength from 1 to 0.01 N. The dependence of the adsorption capacity on the operating conditions was explained by considering the interactions between the DCF in solution and the surface of OBHDTMA. The maximum sorption capacity of the OBHDTMA for DCF was 388 mg/g at T = 25°C and at pH = 7 and was comparable to those of carbon materials. The adsorption of DCF on OBHDTMA was scarcely reversible, but the desorption percentage increased with pH. The adsorption of DCF on OBHDTMA was due to partition and electrostatic attraction. More Cd(II) was adsorbed on OBHDTMA-DCF than on OBHDTMA and this was influenced by the loading of DCF on the OBHDTMA-DCF. The OBHDTMA-DCF may be used to remove Cd(II) from water solution.
Frequency-domain analysis of dual-loop optoelectronic oscillators
Authors: Rahimi Mohammad Mahdi , Jahanbakht Sajad
Published: November 2021

Optoelectronic oscillators (OEOs) are hybrid systems consisting of optical and radio-frequency (RF) parts that are used to produce ultralow phase noise RF oscillations. Dual-loop OEOs can overcome some problems incorporated with single-loop OEOs such as the mode-hopping phenomenon and the large spurious peaks in the phase noise. Therefore, they are usually considered the practical implementation of many OEOs. Here, a frequency-domain steady-state and phase noise analysis approach of these systems is presented, based on the conversion matrix approach. Compared with the existing time-domain analysis approaches, it requires much smaller run times. Compared with the other frequency-domain modeling approaches, such as the linear-time-invariant phase transmission models, it can take all noise-transferring phenomena between various sidebands and all amplitude-noise to phase-noise conversions and vice versa into account. Therefore, it can be regarded as a comprehensive analysis approach to dual-loop OEOs. The validity of the new approach is verified by comparing its results with those of the previously published formulations in the literature.
Two-mirror system for tunable apodization
Authors: González-Acuña Rafael G.
Published: November 2021

Here we present an optical system composed of two mirrors such that at the input/output, the light is a plane wave but with a user-defined apodization factor. The model presented is an analytic closed form with no numerical approximations or iterations. We test the model with illustrative scenarios, and the results are as expected; the system is stigmatic with the desired apodization factor. Thus, this system has several potential applications in high contrast imaging.
Autobalanced spectroscopy of CPT resonance in an optically dense atomic ensemble
Authors: Barantsev Konstantin , Litvinov Andrey
Published: November 2021

We investigate the influence of optical thickness on the coherent population trapping (CPT) resonance interrogated by the autobalanced Ramsey method as well as by the method of combined error signals (CESs). We analyze sensitivity of the CPT resonance to the light shift of the etalon transition for the microwave quantum frequency standards based on cold or hot atomic ensembles. When the CPT resonance is excited, two-frequency laser radiation can be significantly absorbed at the atomic transitions of the optical range. The effects of absorption and phase incursion lead to additional shift of the reference resonance. This is an additional factor that degrades the accuracy of the frequency standards because this additional shift can vary with intensity and temperature fluctuations. It was shown that the CES method is more robust in an optically dense medium than is the autobalanced Ramsey method, but it also undergoes the light shift. We found that by choosing the normalization factor of the CES method it is possible to suppress the light shift for a certain density of the medium or suppress its sensitivity to temperature fluctuations.
Efficient method for the compensation of dispersion mismatch in the frequency-scanning interferometry
Authors: Zhou Qiang , Wu Tengfei , Liu Yang , Shang Yue , Lin Jiarui , Yang Linghui , Li Jianshuang , Zeng Zhoumo , Zhu Jigui
Published: November 2021

Absolute distance measurements could be achieved by the technique of frequency scanning interferometry (FSI), which could provide a micron-level accuracy over several tens of meters. However, as the scanning range and distance increasing, the measurement accuracy and resolution would be seriously influenced by the dispersion mismatch effect, which is mainly caused by the dispersion difference between optical fiber and air. A dispersion compensation method was proposed in this paper, and the mismatch effect would be suppressed effectively without complicated calculations for each single measurement. The chirp in resampling clock would be corrected with a pre-calibration procedure, and the compensation factor is demonstrated for different distances. A calibration method of dispersion compensation factor is also proposed, and the linear regression residual is employed as the criterion. Then, the compensation method is evaluated by experiments with different spatial distances and scanning ranges. Finally, a 60-m experiment is carried out for accuracy comparison, and the measurement accuracy is better than 15 µm by comparing with commercial interferometers.
High accuracy measurement of Poisson’s ratio of optical fibers and its temperature dependence using forward-stimulated Brillouin scattering
Authors: Sánchez L. A. , Díez A. , Cruz J. L. , Andrés M. V.
Published: November 2021

Transverse acoustic mode resonances enable a high accuracy determination of Poisson’s ratio and elastic properties of optical fibers. An all-optical pump and probe technique is used for efficient excitation and accurate characterization of both, radial and torsional-radial acoustic resonances of optical fibers. Simple and precise algebraic expressions for the frequencies of high order acoustic resonances are derived, enabling a rigorous analysis of the experimental data using standard least squares fitting. Following this approach, the determination of Poisson’s ratio does not require the measurement of any physical length, but only frequency measurements are required. An accuracy better than 1 ‰ is achieved. The dependence of the fiber Poisson’s ratio with temperature is also determined experimentally.
Intelligent classification of ground-based visible cloud images using a transfer convolutional neural network and fine-tuning
Authors: Wang Min , Zhuang Zhihao , Wang Kang , Zhou Shudao , Liu Zhanhua
Published: November 2021

Here a classification method for ground-based visible images is proposed based on a transfer convolutional neural network (TCNN). This approach combines the ability of deep learning (DL) and transfer learning (TL). A sample database containing all ten cloud types was used; this database was expanded four-fold using enhancement processing. AlexNet was chosen as the basic convolutional neural network (CNN), with the ImageNet database being used for pre-transfer. The optimal method, once determined by layer-by-layer fine-tuning, was used to test the classification effects for ten cloud types. The proposed method achieved 92.3% recognition accuracy for all ten ground-based cloud types.
Phase imaging microscopy under the Gabor regime in a minimally modified regular bright-field microscope
Authors: Micó Vicente , Trindade Karina , Picazo-Bueno José Ángel
Published: November 2021

Quantitative phase imaging (QPI) is nowadays a powerful tool for visualization and analysis of biological processes. QPI is usually attained from specifically designed optical microscopes retrieving phase information in a quantitative way. In this paper we report on an extremely simple, low cost and compact way to update a standard bright-field microscope with coherent sensing capabilities. It is based on the in-line Gabor holography concept and only needs to replace the illumination broadband source of the regular microscope with a coherent one. The proposed methodology is completed by the recording of a digital in-line Gabor hologram instead of regular imaging conditions and by the numerical processing of the recorded hologram to finally achieve QPI. The selection of the defocus distance is critical to finally achieve high quality phase imaging, so calibration considering phase and amplitude test targets is presented for the proper definition of such defocus distance. In addition, the selected configuration is experimentally validated using different samples (microbeads, cheek cells and alive spermatozoa). All the experiments are implemented in a regular Olympus BX-60 upright microscope using a 20X 0.46NA objective lens. The proposed method shows how to convert a regular microscope into a holographic one with probably the minimum needed modifications and with the main limitation coming from the Gabor imaging conditions (weak diffractive samples and twin image presence).
Kerr-lens mode-locked Yb:SrLaAlO4 laser
Authors: Lin Zhang-Lang , Zeng Huang-Jun , Zhang Ge , Xue Wen-Ze , Pan Zhongben , Lin Haifeng , Loiko Pavel , Liang Hsing-Chih , Petrov Valentin , Mateos Xavier , Wang Li , Chen Weidong
Published: November 2021

We report on the first Kerr-lens mode-locked laser based on the Yb3+-doped disordered strontium lanthanum aluminate crystal, Yb:SrLaAlO4 (Yb:SALLO), pumped by a high-brightness Yb fiber laser at 976 nm. Nearly Fourier-limited pulses as short as 44 fs were achieved at 1051 nm with an average output power of 277 mW and a pulse repetition rate of ∼66 MHz via soft-aperture Kerr-lens mode-locking. A higher average output power of 459 mW, corresponding to an optical efficiency of 33.8%, was obtained at the expense of a slightly longer duration (52 fs).
Self-pulsations in a microcavity Brillouin laser
Authors: Qin Yingchun , Ding Shulin , Lei Shujian , Liu Jie , Bai Yan , Zhang Menghua , Li Yuhang , Wen Jianming , Jiang Xiaoshun , Xiao Min
Published: November 2021

We demonstrate a new, to the best of our knowledge, kind of self-pulsation in a microcavity Brillouin laser. This specific self-pulsation is generated by the interplay between the Brillouin lasing and the thermo-optic effect in an optical microcavity. Intriguingly, the self-pulsation behaviors are simultaneously present in both forward input pump and backward Brillouin lasing emission. By developing a coupled-mode theory, our numerical simulations display an excellent agreement with the experimental results.
Self-mode-locking in a high-power hybrid silicon nitride integrated laser
Authors: Klaver Yvan , Epping Jörn P. , Roeloffzen Chris G. H. , Marpaung David A. I.
Published: November 2021

Integrated mode-locked lasers are useful tools in microwave photonic
applications as a local oscillator. In particular, hybrid integrated
lasers could easily be integrated with passive processing circuits. In
this Letter, we report on the self-mode-locking of a hybrid integrated
laser comprising two indium phosphide gain sections and a silicon
nitride feedback circuit that filters light using two ring resonators.
The hybrid laser is shown to mode-lock and to have a mostly
frequency-modulated field in the cavity using a stepped-heterodyne
optical complex spectrum analysis. A mostly frequency modulated field
output is good for high powers per line due to a more continuous
emission, compared with mode-locked lasers using a saturable absorber;
additionally, the filter limits the bandwidth of the comb, condensing
the power to the fewer comb lines.
Ultrafast multi-photon excitation of ScVO4:Bi3+ for luminescence thermometry
Authors: Escofet-Martin David , Ojo Anthony O. , Peterson Brian
Published: November 2021

We demonstrate a multi-photon excitation (MPE) scheme for luminescence thermometry using ScVO4:Bi3+. MPE is performed using a 37 fs Ti:sapphire laser pulse centered at 800 nm. Log-log plots of the phosphorescence intensity versus excitation power show that the 800 nm MPE of ScVO4:Bi3+ involves a 2- and 3-photon absorption process in comparison with a single-photon excitation (SPE) process at 266 and 400 nm. Spectroscopic investigation shows that with the 800 nm MPE and 266 nm SPE schemes, the emission spectra of ScVO4:Bi3+ are similarly characterized by emissions of the VO43− groups and Bi3+. MPE is advantageous to suppress fluorescence that interferes with the phosphorescence signal. We demonstrate this aspect for a ScVO4:Bi3+ coating applied on an alumina substrate. The luminescence lifetime is calibrated with temperature in the range of 294–334 K; the MPE scheme has an equally impressive temperature sensitivity (3.4–1.7%/K) and precision (0.2–0.7 K) compared with the SPE schemes. The MPE scheme can be applied to a variety of phosphors and is valuable for precise temperature measurements, even in applications where isolating interfering background emissions is challenging.
Comparative genomic analysis reveals varying levels of mammalian adaptation to coronavirus infections
Authors: King Sean B. , Singh Mona
Published: November 2021

Severe acute respiratory coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, is of zoonotic origin. Evolutionary analyses assessing whether coronaviruses similar to SARS-CoV-2 infected ancestral species of modern-day animal hosts could be useful in identifying additional reservoirs of potentially dangerous coronaviruses. We reasoned that if a clade of species has been repeatedly exposed to a virus, then their proteins relevant for viral entry may exhibit adaptations that affect host susceptibility or response. We perform comparative analyses across the mammalian phylogeny of angiotensin-converting enzyme 2 (ACE2), the cellular receptor for SARS-CoV-2, in order to uncover evidence for selection acting at its binding interface with the SARS-CoV-2 spike protein. We uncover that in rodents there is evidence for adaptive amino acid substitutions at positions comprising the ACE2-spike interaction interface, whereas the variation within ACE2 proteins in primates and some other mammalian clades is not consistent with evolutionary adaptations. We also analyze aminopeptidase N (APN), the receptor for the human coronavirus 229E, a virus that causes the common cold, and find evidence for adaptation in primates. Altogether, our results suggest that the rodent and primate lineages may have had ancient exposures to viruses similar to SARS-CoV-2 and HCoV-229E, respectively.
EHMT2 suppresses the variation of transcriptional switches in the mouse embryo
Authors: Zeng Tie-Bo , Pierce Nicholas , Liao Ji , Singh Purnima , Lau Kin , Zhou Wanding , Szabó Piroska E.
Published: November 2021

EHMT2 is the main euchromatic H3K9 methyltransferase. Embryos with zygotic, or maternal mutation in theEhmt2gene exhibit variable developmental delay. To understand how EHMT2 prevents variable developmental delay we performed RNA sequencing of mutant and somite stage-matched normal embryos at 8.5–9.5 days of gestation. Using four-way comparisons between delayed and normal embryos we clarified what it takes to be normal and what it takes to develop. We identified differentially expressed genes, for exampleHoxgenes that simply reflected the difference in developmental progression of wild type and the delayed mutant uterus-mate embryos. By comparing wild type and zygotic mutant embryos along the same developmental window we detected a role of EHMT2 in suppressing variation in the transcriptional switches. We identified transcription changes where precise switching during development occurred only in the normal but not in the mutant embryo. At the 6-somite stage, gastrulation-specific genes were not precisely switched off in theEhmt2−/−zygotic mutant embryos, while genes involved in organ growth, connective tissue development, striated muscle development, muscle differentiation, and cartilage development were not precisely switched on. TheEhmt2mat−/+maternal mutant embryos displayed high transcriptional variation consistent with their variable survival. Variable derepression of transcripts occurred dominantly in the maternally inherited allele. Transcription was normal in the parental haploinsufficient wild type embryos despite their delay, consistent with their good prospects. Global profiling of transposable elements revealed EHMT2 targeted DNA methylation and suppression at LTR repeats, mostly ERVKs. InEhmt2−/−embryos, transcription over very long distances initiated from such misregulated ‘driver’ ERVK repeats, encompassing a multitude of misexpressed ‘passenger’ repeats. In summary, EHMT2 reduced transcriptional variation of developmental switch genes and developmentally switching repeat elements at the six-somite stage embryos. These findings establish EHMT2 as a suppressor of transcriptional and developmental variation at the transition between gastrulation and organ specification.
Combining the strengths of inverse-variance weighting and Egger regression in Mendelian randomization using a mixture of regressions model
Authors: Lin Zhaotong , Deng Yangqing , Pan Wei
Published: November 2021

With the increasing availability of large-scale GWAS summary data on various traits, Mendelian randomization (MR) has become commonly used to infer causality between a pair of traits, an exposure and an outcome. It depends on using genetic variants, typically SNPs, as instrumental variables (IVs). The inverse-variance weighted (IVW) method (with a fixed-effect meta-analysis model) is most powerful when all IVs are valid; however, when horizontal pleiotropy is present, it may lead to biased inference. On the other hand, Egger regression is one of the most widely used methods robust to (uncorrelated) pleiotropy, but it suffers from loss of power. We propose a two-component mixture of regressions to combine and thus take advantage of both IVW and Egger regression; it is often both more efficient (i.e. higher powered) and more robust to pleiotropy (i.e. controlling type I error) than either IVW or Egger regression alone by accounting for both valid and invalid IVs respectively. We propose a model averaging approach and a novel data perturbation scheme to account for uncertainties in model/IV selection, leading to more robust statistical inference for finite samples. Through extensive simulations and applications to the GWAS summary data of 48 risk factor-disease pairs and 63 genetically uncorrelated trait pairs, we showcase that our proposed methods could often control type I error better while achieving much higher power than IVW and Egger regression (and sometimes than several other new/popular MR methods). We expect that our proposed methods will be a useful addition to the toolbox of Mendelian randomization for causal inference.
Descriptive study of cattle and dog rabies cases in the Sheki-Zagatala region of Azerbaijan (2015–2016): Knowledge, attitudes, and practices of people towards rabies
Authors: Hasanov Eldar , Garayusifova Aytan , Tongren Eric Jon , Geleishvili Marika
Published: November 2021

Every year, rabies causes great damage to human health and the economy of countries around the world. This neurotropic and zoonotic viral disease is endemic to Azerbaijan. This study describes cattle and dog rabies cases identified between 2015 and 2016. In addition, a questionnaire was administered to 100 respondents comprised of case owners, and non-case animal owners, to assess knowledge, attitudes, and practices within this population. The study demonstrates a general lack of knowledge of rabies in the participating communities. The majority of respondents were familiar with rabies and understood that animal bites are a source of transmission. However, many respondents did not know that rabies is preventable and admitted not knowing additional routes of transmission. In addition, there was less perceived risk with contact with animal saliva. Despite free vaccinations in Azerbaijan, only 27 out of 45 dogs in this study were vaccinated. Although educational programming and preventive vaccination of dogs has been implemented, and significant progress has been made in the sphere of epidemiological surveillance and prevention, rabies cases remain problematic in the Sheki-Zagatala region. Regular educational programs for communities, strengthening of the existing vaccination programs, and a comprehensive epidemiological case-control study to identify the disease risk factors could help reduce the burden of rabies in Azerbaijan.
Patterns of serum immune biomarkers during elephant endotheliotropic herpesvirus viremia in Asian and African elephants
Authors: Edwards Katie L. , Latimer Erin M. , Siegal-Willott Jessica , Kiso Wendy , Padilla Luis R. , Sanchez Carlos R. , Schmitt Dennis , Brown Janine L.
Published: November 2021

Hemorrhagic disease (HD) caused by a group of elephant endotheliotropic herpesviruses (EEHV) is one of the leading causes of death for young elephants in human care. These viruses are widespread and typically persist latently in adult elephants with no negative effects; however, in juvenile Asian and more recently young African elephants, the onset of disease can be rapid and the mortality rate high. Measuring biomarkers associated with the immune response could be beneficial to understanding underlying disease processes, as well as the management of infection and HD. The goal of this study was to measure acute phase proteins and cytokines in serum collected from elephants infected with EEHV (13 Asian and 1 African) and compare concentrations according to presence, severity and outcome of disease. Serum amyloid A (SAA) and haptoglobin (HP) were higher in elephants with EEHV viremia than those without; concentrations increased with increasing viral load, and were higher in fatal cases compared to those that survived. In Asian elephants, SAA was also higher during EEHV1 viremia compared to EEHV5. Cytokine concentrations were typically low, and no statistical differences existed between groups. However, in individuals with detectable levels, longitudinal profiles indicated changes in tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) that may reflect an immune response to EEHV infection. However, the overall low concentrations detected using previously validated assays do not support the presence of a ‘cytokine storm’ and suggest more work is needed to understand if sub-optimal immune responses could be involved in disease progression. These results highlight the potential benefit of measuring circulating biomarker concentrations, such as APPs and cytokines, to improve our understanding of EEHV viremia and HD, assist with monitoring the progression of disease and determining the impact of interventions.