bluuebunny/crossref_metadata_2025 huggingface dataset:
The energy level of the diet in Holstein cows in the first third of lactation alters the expression of immune genes in the mammary gland
Authors: Gómez‐Martínez Juan Esteban , Rodríguez‐Osorio Nélida , Echeverri‐Zuluaga José Julián , López‐Herrera Albeiro
Published: November 2020

Our goal was to define the effect of the energy intake in Holstein cows’ diet in the first third lactation on gene expression profile of immune system in mammary gland through RNA‐seq. Twelve Holstein cows were used in the first third of lactation, arranged in four treatments or diets: (a) hypocaloric (HYPO, 85% of the net energy of lactation (NEl) requirements), (b) isocaloric (ISO, 100% of the NEl requirements, control diet), (c) hypercaloric (HYPER, 115% of the NEl requirements) and (d) isocaloric plus sunflower oil supplementation (OIL, 106% of the NEl requirements). A biopsy of mammary gland tissue was carried out after 25 days per diet, from which the RNA was extracted and sequenced using the Illumina HiSeqTM 2,500 sequencer. The analysis of reads obtained from the sequencing in the QIAGEN® CLC Genomics Workbench 10.0 bioinformatics software was performed. From 27,368 genes annotated in the reference genome, 17,429 genes expressed in the evaluated treatments were identified. Moreover, 1,743 differentially expressed genes (DEGs) were found, of which 15 DEGs were found in the ISO vs. OIL comparison, 1,196 DEGs in the ISO vs. HYPO comparison and 532 DEGs in the ISO vs. HYPER comparison. Thus, of the 1,743 DEGs, 401 correspond to genes involved in the functioning of the immune system, encompassing 23% of the total number of DEGs involved in the analysis, and 13.6% of the total number of genes involved in the functioning of the immune system. The energy intake in Holstein cows’ diet has impact in the expression of immune genes CXCL13, TRDC among others, present in the regulation of immune system processes. This immune system altered might increase the somatic cells score and therefore reach some diseases. It is recommended to measure the energy intake according to the animals’ energy requirements and to cover them the closest to the 100%.
Perioperative pharmacokinetics and pharmacodynamics of meloxicam in emus (Dromaius novaehollandiae) of different age groups using nonlinear mixed effect modelling
Authors: Castineiras Diego , Armitage Lucy , Lamas Luís Pardon , De Baere Siegrid , Croubels Siska , Pelligand Ludovic
Published: November 2020

Meloxicam is a widely used nonsteroidal anti‐inflammatory drug in avian species. However, variability in pharmacokinetic (PK) and pharmacodynamic (PD) parameters in birds warrants species‐specific studies for dose and dosing interval optimization. We performed a perioperative PK study of meloxicam (0.5 mg/kg, intravenously) on emus of three different age groups: 3 chicks (5 weeks old, 3.5 kg), 4 juveniles (26 weeks old, 18.8 kg) and 6 adults (66 weeks old, 38.8 kg). A two‐compartment population PK model including weight as a significant covariate on clearance and central volume of distribution (V1) best fitted the data. The typical values (20 kg bird) for clearance and V1 were 0.54 L/kg/h and 0.095 L/kg. Both parameters significantly decreased with increasing weight/age. Meloxicam potency and selectivity for COX‐1 and COX‐2 were measured in whole blood assays (TxB2 production endpoint). Meloxicam was partially selective in emus (IC50 COX‐1:COX‐2 = 9.1:1). At the current empirical dose (0.5 mg/kg/24 hr), plasma meloxicam concentration is above IC50 of COX‐2 for only 2 hr. PK/PD predicted dose required for 80% COX‐2 inhibition over 24 hr were 3.4, 1.4 and 0.95 L/kg/day in chicks, juveniles and adult emus, respectively. The safety, therapeutic efficacy and practicality of modifying the daily dose or dose interval should be considered for dose recommendations in emus.
CryoEM of bacterial secretion systems: A primer for microbiologists
Authors: Umrekar Trishant R. , Cohen Eli , Drobnič Tina , Gonzalez‐Rodriguez Nayim , Beeby Morgan
Published: November 2020

“CryoEM” has come of age, enabling considerable structural insights into many facets of molecular biology. Here, we present a primer for microbiologists to understand the capabilities and limitations of two complementary cryoEM techniques for studying bacterial secretion systems. The first, single particle analysis, determines the structures of purified protein complexes to resolutions sufficient for molecular modeling, while the second, electron cryotomography and subtomogram averaging, tends to determine more modest resolution structures of protein complexes in intact cells. We illustrate these abilities with examples of insights provided into how secretion systems work by cryoEM, with a focus on type III secretion systems.
Achalasia: physiology and diagnosis
Authors: Rieder Erwin , Fernandez‐Becker Nielsen Q. , Sarosiek Jerzy , Guillaume Alexandra , Azagury Dan E. , Clarke John O.
Published: November 2020

Achalasia is a rare motility disorder with incomplete relaxation of the lower esophageal sphincter and ineffective contractions of the esophageal body. It has been hypothesized that achalasia does not result from only one pathway but rather involves a combination of infectious, autoimmune, and familial etiological components. On the basis of other observations, a novel hypothesis suggests that a muscular form of eosinophilic esophagitis is involved in the pathophysiology of achalasia in some patients. This appears to progressively diminish the myenteric plexus at stage III, gradually destroy it at stage II, and finally eliminate it at stage I, the most advanced and final stage of achalasia. Although high‐resolution manometry has identified these three different types of achalasia, another subset of patients with a normal‐appearing sphincter relaxation has been proposed. Provocative maneuvers, such as the rapid drinking challenge, have recently been demonstrated to improve diagnosis in certain borderline patients, but have to be studied in more detail. However, whether the different types of achalasia will have a long‐term impact on tailored therapies is still a matter of debate. Additionally, novel aspects of the standard timed barium swallow appear to be an important adjunct of diagnosis, as it has been shown to have a diagnostic as well as a predictive value.
Classification of submandibular salivary stones based on ultrastructural studies
Authors: Tretiakow Dmitry , Skorek Andrzej , Wysocka Joanna , Darowicki Kazimierz , Ryl Jacek
Published: November 2020

Introduction

Sialolithiasis remains a clinical problem with unclear etiopathogenesis, lack of prevention methods, and only surgical treatment.

Materials and methods

An ultrastructure examination of submandibular sialoliths obtained from patients with chronic sialolithiasis was conducted using a scanning electron microscope and X‐ray photoelectron spectroscopy.

Results

Based on the results, we divided sialoliths into three types: calcified (CAL), organic/lipid (LIP), and mixed (MIX). The core structure of the CAL and MIX is very similar. The core of the LIP has a prevalence of organic components. The intermediate layers’ structure of the CAL is different from LIP and MIX. In LIP and MIX, the organic component begins to increase in intermediate layers rapidly. The structure of the superficial layers for all types of sialoliths is similar.

Conclusions

We introduced a new classification of the submandibular salivary gland stones. Based on the results, it can be said that sialoliths type CAL and LIP have their separate path of origin and development, while MIX is formed as CAL stone, and the further pathway of their growth passes as LIP stones. Organic components were much more than inorganic in all layers of salivary gland stones, which highly prevents their dissolution in the patient's salivary gland duct.
Plant–plant facilitation increases with reduced phylogenetic relatedness along an elevation gradient
Authors: Duarte Milen , Verdú Miguel , Cavieres Lohengrin A. , Bustamante Ramiro O.
Published: November 2020

Environmental conditions can modify the intensity and sign of ecological interactions. The stress gradient hypothesis (SGH) predicts that facilitation becomes more important than competition under stressful conditions. To properly test this hypothesis, it is necessary to account for all (not a subset of) interactions occurring in the communities and consider that species do not interact at random but following a specific pattern. We aim to assess elevational changes in facilitation, in terms of species richness, frequency and intensity of the interaction as a function of the evolutionary relatedness between nurses and their associated species. We sampled nurse and their facilitated plant species in two 1000–2000 m. elevation gradients in Mediterranean Chile where low temperature imposes a mortality filter on seedlings. We first estimated the relative importance of facilitation as a mechanism adding new species to communities distributed along these gradients. We then tested whether the frequency and intensity of facilitation increases with elevation, taking into account the evolutionary relatedness of the nurse species and the facilitated species.

We found that nurses increase the species richness of the community by up to 35%. Facilitative interactions are more frequent than competitive interactions (56% versus 44%) and facilitation intensity increased with elevation for interactions involving distantly related lineages.

Our results highlight the importance of including an evolutionary dimension in the study of facilitation to have a clearer picture of the mechanisms enabling species to coexist and survive under stressful conditions. This knowledge is especially relevant to conserve vulnerable and threatened communities facing new climate scenarios, such as those located in Mediterranean‐type ecosystems.
Important considerations for drugs, nutritional, and herbal supplements in pediatric solid organ transplant recipients
Authors: Pilch Nicole A. , Sell Megan L. , McGhee William , Venkataramanan Raman
Published: November 2020

Pediatric transplant recipients are on multiple prescription and non‐prescription drugs. Many patients also use dietary, nutritional, and herbal supplements. This manuscript researched formulations of immunosuppressive drugs currently available and presents information on generic immunosuppressive drugs, commonly used non‐prescription medications, dietary supplements, and herbal supplements. Immunosuppressive drugs are available in various formulations. Not all formulations are interchangeable. A number of FDA‐approved generic formulations are available commercially in the United States. Generally generic formulations produce similar blood concentration vs time profiles compared to brand name products in adults and are considered to be bioequivalent. NSAID should be avoided in transplant patients due to potential drug interactions and increased risk associated with NSAID use; and appropriate doses of acetaminophen should be used for treatment of pain. Over‐the‐counter medications, such as guaifenesin and dextromethorphan, antihistamine medications, including diphenhydramine, loratadine, cetirizine, and fexofenadine, can be safely used in pediatric solid organ transplant population. Many safe and effective over‐the‐counter options exist for stool softening and as laxative. Diarrhea can lead to an increase in calcineurin inhibitor levels. Food can alter the absorption of immunosuppressive drugs. Several herbal products can alter immune status of the patients or alter the blood concentration of immunosuppressive drugs or may produce renal or hepatic toxicities and should be avoided in pediatric transplant recipients. It is important to educate pediatric transplant recipients and their families about not only immunosuppressive drug therapy but also about non‐prescription drugs, dietary, and herbal supplement use.
Multicenter data to improve health for pediatric renal transplant recipients in North America: Complementary approaches of NAPRTCS and IROC
Authors: Hooper David K. , Misurac Jason , Blydt‐Hansen Tom , Chua Annabelle N.
Published: November 2020

Kidney transplantation increases life expectancy and improves quality of life for children with end‐stage kidney disease, yet sequelae of transplantation and treatment make it difficult for transplant recipients to enjoy health and quality of life similar to their healthy peers. The NAPRTCS network was among the first to use multicenter data to inform improvements in care and outcomes for children with a kidney transplant through observational research. Now, with new technologies and unprecedented access to data, it is possible to create learning health systems as envisioned by the US National Academy of Sciences to seamlessly integrate research and continuous improvement of clinical care. In this review, we present two pre‐eminent North American networks focused on using multicenter data to drive improved care and outcomes for children with a kidney transplant. Whereas, for the past 30 years NAPRTCS has focused on discovery of best practices through observational research and clinical trials, the Improving Renal Outcomes Collaborative, established in 2016, engages patients, families, clinicians, and researchers in redesigning the healthcare delivery system to enable practice change and continuous improvement of health outcomes. We discuss the history and past contributions of these networks, as well as current activities, barriers, and potential future solutions to more fully realize the vision of a true learning health system for pediatric kidney transplant recipients.
Allogeneic hematopoietic stem cell transplant in pediatric acute myeloid leukemia: Lessons learnt from a tertiary care center in India
Authors: Arora Shalabh , Pushpam Deepam , Tiwari Akash , Choudhary Priyanshu , Chopra Anita , Gupta Ritu , Kumar Rajive , Bakhshi Sameer
Published: November 2020

There is paucity of data on outcomes of MSD‐HSCT in children with relapsed or high‐risk AML from developing countries, which have unique challenges including adverse host factors and resource constraints. We retrospectively reviewed records of children (age ≤ 18 years) who underwent MSD‐HSCT for AML at our center from 2009 to 2019 to evaluate clinical outcome and its predictors using Cox proportional hazards model. There were 46 children (36 boys and 10 girls) with mean age 10.7 ± 4.8 years. Indication for HSCT was relapsed AML in CR2 (n = 37), primary refractory (n = 3), or relapsed refractory disease (n = 3); high‐risk (n = 1) or secondary (n = 2) AML in CR1. Five‐year EFS and OS were 33.3 ± 7.2% and 36.3 ± 7.6%, respectively. On multivariate analysis, CR1 duration less than 12 months, presence of active disease at transplant, and use of bone marrow stem cell graft were associated with poorer EFS and OS. There was one (2.2%) TRM, while disease relapse occurred in 20/40 patients who underwent HSCT in remission. Though the 5‐year EFS and OS were inferior to results reported from high‐income countries, relapse (and not TRM) was the major cause of treatment failure. A well‐sustained CR1, achievement of disease remission, and use of peripheral blood allograft seem imperative to a successful transplant. Targeted therapy along with HSCT may be the option for those with early relapse.
Strategy (Part I): Conceptual Foundations
Authors: Silver Kenneth
Published: November 2020

Strategies are mentioned across a variety of domains, from business ethics, to the philosophy of war, philosophy of sport, game theory, and others. However, despite their wide use, very little has been said about how to think about what strategies are or how they relate to other prominently discussed concepts. In this article, I probe the close connection between strategies and plans, which have been much more thoroughly characterized in the philosophy of action. After highlighting the challenges of analyzing strategies in terms of plans, I show how the work done on the connection between plans and intentions can inspire further questions about the nature of strategy. I conclude by showing how one particular innovation in the understanding of plans—how they can be more or less partial—can be used to help us to mark what makes for a good strategy.
Leaving the Barracks: Military Coups in Developing Democracies
Authors: Hunter Lance Y. , Rutland Josh , King Zachary
Published: November 2020

A large body of research has examined the factors that influence military coups in authoritarian and democratic states. While this research is informative, we contend that three factors are central in assessing the likelihood of military coups in developing democracies: the perception of corruption within regimes, levels of popular support, and the incentives segments of the military have to initiate coups. In utilizing a historical case‐study analysis with six states in Africa, Asia, and Latin America (from 1970‐2010) we find that successful military coups are more likely to occur when the ruling administration is increasingly viewed by the public as being corrupt, is unpopular with large portions of society and key factions within the state, and when segments of the military perceive their position within the state as being threatened by the current regime. These findings have important implications for democratic governance in developing democracies.

Related Articles:

Hiroi, Taeko, and Sawa Omori. 2013. “Causes and Triggers of Coups d'état: An Event History Analysis.” Politics & Policy 41 (1): 39‐64. https://doi.org/10.1111/polp.12001

Kim, Hae S. 2009. “The Complexities of Internal Conflict in the Third World: Beyond Ethnic and Religious Conflict.” Politics & Policy 37 (2): 395‐414. http://onlinelibrary.wiley.com/doi/10.1111/j.1747‐1346.2009.00177.x/abstract

McCarthy‐Jones, Anthea, and Mark Turner. 2015. “Policy Transfer through Time and the Search for Legitimacy in Developing Nations.” Politics & Policy 43 (2): 215‐238. https://doi.org/10.1111/polp.12113
Time course of the unmasked attentional blink
Authors: Ching April Shi Min , Kim Jeesun , Davis Chris
Published: November 2020

The Attentional Blink (AB) usually refers to the impaired report of a second target (T2) if it appears within 200–500 ms after a first target within a rapid sequence of distractors. The present study focused on a less studied AB variant known as the unmasked AB, where T2 is the last item of the sequence and T2 report is unaffected. This aspect of the unmasked AB holds promise for an experimental paradigm in which measures of on‐going event‐related processing are unconfounded by differences in late‐stage processing. To fully characterize the unmasked AB paradigm, we used a randomization statistics approach to comprehensively examine the electroencephalographic signature of the unmasked AB. We examined the unmasked AB with auditory and visual T2s—participants attended to either the auditory or visual information within a sequence of paired auditory‐visual stimuli, and reported targets within the attended modality stream while ignoring the other. As predicted, T2 report was unaffected by the unmasked AB. The visual AB was associated with delayed but intact N2 and P3 components, and a suppressed N1. We suggest that this N1 is linked to auditory processing of the distractor stream, and reflects the cognitive system prioritizing the processing of visual targets over auditory distractors in response to AB‐related processing load. The auditory AB only indicated a delayed but intact P3. Collectively, these findings support the view that the AB limits the entry of information into consciousness via a late‐stage modal bottleneck, and suggest an ongoing compensatory response at early latencies.
Pharmacological fMRI provides evidence for opioidergic modulation of discrimination of facial pain expressions
Authors: Zhao Yili , Rütgen Markus , Zhang Lei , Lamm Claus
Published: November 2020

The endogenous opioid system is strongly involved in the modulation of pain. However, the potential role of this system in perceiving painful facial expressions from others has not been sufficiently explored as of yet. To elucidate the contribution of the opioid system to the perception of painful facial expressions, we conducted a double‐blind, within‐subjects pharmacological functional magnetic resonance imaging (fMRI) study, in which 42 participants engaged in an emotion discrimination task (pain vs. disgust expressions) in two experimental sessions, receiving either the opioid receptor antagonist naltrexone or an inert substance (placebo). On the behavioral level, participants less frequently judged an expression as pain under naltrexone as compared to placebo. On the neural level, parametric modulation of activation in the (putative) right fusiform face area (FFA), which was correlated with increased pain intensity, was higher under naltrexone than placebo. Regression analyses revealed that brain activity in the right FFA significantly predicted behavioral performance in disambiguating pain from disgust, both under naltrexone and placebo. These findings suggest that reducing opioid system activity decreased participants' sensitivity for facial expressions of pain, and that this was linked to possibly compensatory engagement of processes related to visual perception, rather than to higher level affective processes, and pain regulation.
Clusters of sleep apnoea phenotypes: A large pan‐European study from the European Sleep Apnoea Database (ESADA)
Authors: Bailly Sébastien , Grote Ludger , Hedner Jan , Schiza Sofia , McNicholas Walter T. , Basoglu Ozen K. , Lombardi Carolina , Dogas Zoran , Roisman Gabriel , Pataka Athanasia , Bonsignore Maria R , Pepin Jean‐Louis ,   ESADA Study Group
Published: November 2020

Background and objective

To personalize OSA management, several studies have attempted to better capture disease heterogeneity by clustering methods. The aim of this study was to conduct a cluster analysis of 23 000 OSA patients at diagnosis using the multinational ESADA.

Methods

Data from 34 centres contributing to ESADA were used. An LCA was applied to identify OSA phenotypes in this European population representing broad geographical variations. Many variables, including symptoms, comorbidities and polysomnographic data, were included. Prescribed medications were classified according to the ATC classification and this information was used for comorbidity confirmation.

Results

Eight clusters were identified. Four clusters were gender‐based corresponding to 54% of patients, with two clusters consisting only of men and two clusters only of women. The remaining four clusters were mainly men with various combinations of age range, BMI, AHI and comorbidities. The preferred type of OSA treatment (PAP or mandibular advancement) varied between clusters.

Conclusion

Eight distinct clinical OSA phenotypes were identified in a large pan‐European database highlighting the importance of gender‐based phenotypes and the impact of these subtypes on treatment prescription. The impact of cluster on long‐term treatment adherence and prognosis remains to be studied using the ESADA follow‐up data set.
Tampering with Nature: A Systematic Review
Authors: Hoogendoorn Gea , Sütterlin Bernadette , Siegrist Michael
Published: November 2020

Tampering with nature has been shown to be a strong, and sometimes even the strongest, predictor of the risk perception and acceptance of various technologies and behaviors, including environmental technologies, such as geoengineering. It is therefore helpful to understand what tampering with nature is as a construct, to which factors it relates, and when a technology or behavior is perceived as such. By means of a systematic review, we show that very little systematic research has been conducted on tampering with nature. Because tampering with nature has not yet been clearly defined, no systematic operationalization of tampering with nature has been used in the current literature. We show that tampering with nature is often used interchangeably with other constructs, such as naturalness. Based on the literature, we suggest that tampering with nature is related to and possibly influenced by three other constructs, which are naturalness, morality, and controllability. We discuss the influence of tampering with nature on the acceptance and risk perception of various technologies and behaviors and make suggestions for future research needs in order to better understand this construct.
Inequality Comparisons with Ordinal Data
Authors: Jenkins Stephen P.
Published: November 2020

Non‐intersection of appropriately defined Generalized Lorenz (GL) curves is equivalent to a unanimous ranking of distributions of ordinal data by all Cowell and Flachaire (Economica, 2017) indices of inequality and by a new index based on GL curve areas. Comparisons of life satisfaction distributions for six countries reveal a substantial number of unanimous rankings. The GL dominance criteria are compared with other criteria including the dual‐H dominance criteria of Gravel, Magdalou, and Moyes (Economic Theory, 2020).
Abnormal expression of autophagy‐related proteins in immune thrombocytopenia
Authors: Liu Shu‐yan , Zhang Xiao‐mei , Sun Rui‐Jie , Zhu Jing‐jing , Yuan Dai , Shan Ning‐ning
Published: November 2020

Autophagy is a highly conserved protein degradation pathway that is essential for affecting some autoimmune diseases. Immune thrombocytopenia (ITP) is a common autoimmune disorder, and the complex dysregulation of cellular immunity has been observed; however, the relationship between autophagy‐related proteins and immune responses in ITP remains unclear. Using real‐time quantitative polymerase chain reaction (RT‐PCR), the mRNA expression levels of Beclin‐1, SQSTM1/p62 and LC3 were measured in the peripheral blood mononuclear cells (PBMCs) of 20 newly diagnosed patients with active ITP, 16 ITP patients in remission and 21 healthy volunteers. The stained Beclin‐1 and SQSTM1/p62 proteins were also observed in the bone marrow of active ITP patients and normal controls by immunofluorescence. SQSTM1/p62 mRNA expression in PBMCs in newly diagnosed patients was significantly decreased. At the same time, Beclin‐1 mRNA was increased significantly. During the remission stages, the levels of these autophagy‐related proteins were comparable with those observed in healthy controls. Taken together, these results suggest that the aberrant expression of autophagy‐related proteins might be involved in the pathogenesis of ITP. Further study of the autophagy pathway may provide a new strategy and direction for the treatment of ITP.
Effect of marathon and ultra‐marathon on inflammation and iron homeostasis
Authors: Kaufmann Christoph C. , Wegberger Claudia , Tscharre Maximilian , Haller Paul M. , Piackova Edita , Vujasin Irena , Kassem Mona , Tentzeris Ioannis , Freynhofer Matthias K. , Jäger Bernhard , Wojta Johann , Huber Kurt
Published: November 2020

The physiological response to high‐level endurance exercise, such as running a marathon, poses several beneficial but also potentially harmful metabolic changes. The objective of this study was to determine the impact of marathon (M) and ultra‐marathon (UM) on inflammation and iron homeostasis in paired samples. Fifteen well‐trained, non‐professional endurance athletes (14 males, 1 female) performed both a 130 km ultra‐marathon and a traditional 42.195 km marathon. We determined markers of inflammation and iron homeostasis before, immediately after, and within 5 days after finishing each run, respectively. Biomarkers of inflammation (leucocytes, neutrophil granulocytes, monocytes, and c‐reactive protein [CRP]) increased significantly after both marathon and ultra‐marathon with higher levels of CRP after ultra‐marathon compared with marathon both immediately after the race (18.15 ± 12.41 vs 5.58 ± 9.65 mg/L, P < .001) and at follow‐up (15.67 ± 16.97 vs 7.19 ± 7.75 mg/L, P = .045) Concentrations of ferritin also increased significantly after both races and remained high at follow‐up. Higher levels of ferritin immediately after the race (111.5 ± 103.2 vs 84.8 ± 86.3, P = .001) and at follow‐up (102.7 ± 79.5 vs 74.6 ± 65.6, P = .001) were found in ultra‐marathon finishers. The observed increase of serum iron and transferrin saturation (TSAT) after marathon and the decrease of serum iron and TSAT after ultra‐marathon resulted in a significant absolute difference between the two races. The present data suggest a higher degree of inflammation after ultra‐marathon compared with marathon. Markers of iron homeostasis also showed different response patterns with regard to running distance.
Clinical value of high‐resolution dynamic contrast‐enhanced (DCE) MRI in diagnosis of cutaneous squamous cell carcinoma
Authors: Tang Mengxiao , Huang Renjun , Chen Jianhua , Sheng Meiying , Zhang Zhongshuai , Xing Jianming , Guo Lingchuan , Li Yonggang
Published: November 2020

Background

While uncomplicated cases of skin squamous cell carcinoma (cSCC) can be treated with surgery topical therapy alone, more objective and non‐invasive examination methods are needed to guide clinicians to make more detailed biopsy and surgical plans for lesions with atypical or subcutaneous growth. High‐resolution magnetic resonance imaging (HR‐MRI) is a novel skin imaging method.

Materials and methods

Prospective collection of 19 patients with clinically suspected cSCC. All patients underwent high‐resolution DCE‐MRI using a 70‐mm microscopy coil before operation. The imaging features and results of surgical pathology were recorded. Ktrans, Kep, Ve values, and the time‐signal curve (TIC) types were determined using DCE images.

Results

16 cases of cSCC, 3 cases of acanthoma. The subcutaneous invasion of all lesions was clearly displayed, of which 8 lesions invaded the subcutaneous fat layer, 5 invaded the muscle layer, 1 invaded the periosteum, 2 invaded the cap fascia, and the layer of all lesions invasion judged by HR‐MR imaging was consistent with the postoperative pathology. The main manifestations of cSCC were ill‐defined margin, obvious inhomogeneous enhancement, higher perfusion parameters value and type‐III TIC, while acanthoma showed well‐defined and type‐I TIC. Some imaging findings (such as boundary, enhancement) and DCE perfusion parameters of the two groups overlap.

Conclusion

High‐resolution DCE‐MRI can fully and directly display the subcutaneous invasion of cSCC, and more work needs to be done to prove its value. Next, we will expand the sample size, and further explore its value in the differential diagnosis and prognosis evaluation of cSCC from acanthoma or other skin tumors.
CFM1, a member of the CRM‐domain protein family, functions in chloroplast group II intron splicing in Setaria viridis
Authors: Feiz Leila , Asakura Yukari , Mao Linyong , Strickler Susan R. , Fei Zhangjun , Rojas Margarita , Barkan Alice , Stern David B.
Published: November 2020

The chloroplast RNA splicing and ribosome maturation (CRM) domain is a RNA‐binding domain found in a plant‐specific protein family whose characterized members play essential roles in splicing group I and group II introns in mitochondria and chloroplasts. Together, these proteins are required for splicing of the majority of the approximately 20 chloroplast introns in land plants. Here, we provide evidence from Setaria viridis and maize that an uncharacterized member of this family, CRM Family Member1 (CFM1), promotes the splicing of most of the introns that had not previously been shown to require a CRM domain protein. A Setaria mutant expressing mutated CFM1 was strongly disrupted in the splicing of three chloroplast tRNAs: trnI, trnV and trnA. Analyses by RNA gel blot and polysome association suggest that the tRNA deficiencies lead to compromised chloroplast protein synthesis and the observed whole‐plant chlorotic phenotypes. Co‐immunoprecipitation data demonstrate that the maize CFM1 ortholog is bound to introns whose splicing is disrupted in the cfm1 mutant. With these results, CRM domain proteins have been shown to promote the splicing of all but two of the introns found in angiosperm chloroplast genomes.
Abundance of Rhamphicarpa fistulosa in rainfed lowland rice fields in the Savannah region of Togo: Moderate influence of physico‐chemical characteristics of soils
Authors: Houngbedji Tossimidé , Dessaint Fabrice , Nicolardot Bernard , Perronne Rémi , Gibot‐Leclerc Stéphanie
Published: November 2020

Rainfed lowland rice fields in northern Togo are increasingly infested by the facultative hemiparasitic weed Rhamphicarpa fistulosa that is widely reported throughout sub‐Saharan Africa to be one of the most damaging weeds in rice fields. In this geographical area, some studies have shown that soil characteristics may influence the presence and/or the level of infestation of some parasitic weeds, but none have been conducted on R. fistulosa. Based on surveys conducted in northern Togo over two years in 66 lowland rice fields, we characterised the level of infestation of R. fistulosa as well as physico‐chemical characteristics of soils. We highlighted that fields with medium‐to‐high levels of infestation of R. fistulosa (more than 5 plants per m2) were mainly characterised by a coarser soil texture, a higher potassium content and a higher pH, while fields without R. fistulosa were characterised by a lower proportion of silt content. In contrast, the level of infestation of R. fistulosa appeared only marginally influenced by soil organic carbon and nitrogen in our study. Considering these results, options to modify the main physico‐chemical characteristics of soils that influence the level of infestation of R. fistulosa are likely difficult to implement. In order to continue rice production in these lowland fields, we suggest several measures to better manage R. fistulosa seedbank and development.
Prevalence and incidence of adverse events with catheter ablation for adults with Wolff-Parkinson-White syndrome: a systematic review protocol
Authors: Meier Kathleen N. , Tatum Eva C. , Christian Robin , Palokas Michelle
Published: November 2020

Objective:

The objective of this review is to synthesize the best available evidence to determine the prevalence and incidence of adverse events in patients with Wolff-Parkinson-White syndrome who have undergone catheter ablation.

Introduction:

Wolff-Parkinson-White syndrome is a rare congenital heart disease affecting the normal cardiac conduction system that predisposes an individual to tachyarrhythmias. Patients with Wolf-Parkinson-White syndrome can experience a wide range of life-threatening symptoms and frequently undergo catheter ablation procedures to treat this disease. These patients are at risk of developing a variety of adverse events, including pericardial effusion, cardiac tamponade, atrial fibrillation, stroke, cerebral hemorrhage, major bleeding or hematoma, deep vein thrombosis, atrioventricular-block, cardiac perforation, coronary artery injury, pulmonary emboli, and death.

Inclusion criteria:

This review will include adults aged 18 or older with a diagnosis of Wolff-Parkinson-White syndrome who have undergone catheter ablation, including radiofrequency ablation and cryoablation.

Methods:

MEDLINE, CINAHL, Scopus, Embase, and Web of Science databases will be searched from 1980 to the present for English-language studies only. Prevalence and incidence data, experimental, quasi-experimental, observational, and descriptive studies will be included and critically appraised by two independent reviewers. Data will be extracted using the standardized data extraction tool for prevalence data. If sufficient data is available, a meta-analysis will be conducted; otherwise, the findings will be presented in narrative form including tables and figures to aid in data presentation where appropriate.

Systematic review registration number:

PROSPERO CRD42020180391
Damper Force Characteristics of a Separated Dual-Chamber Single-Rod Type Damper Utilizing an Elastomer Particle Assemblage in the Case of Both Chambers Containing Particles
Authors: Toyouchi Atsushi , Ido Yasushi , Iwamoto Yuhiro , Hanai Makoto
Published: November 2020

Particle dampers that use soft/hard particles are attracting attention as a solution to problems such as oil leakage of oil dampers and the temperature dependence of their characteristics. Particle dampers effectively attenuate vibration using the friction and inelastic normal collisions generated between particles or between particles and walls. Here, the effects of the packing fraction of particles, the vibration frequency, and hardness of the material on the damper force characteristics of a separated dual-chamber single-rod type damper with elastomer particle assemblages were investigated experimentally. The maximal damper force and its hysteresis increased with the packing fraction, the vibration frequency, and the Young’s modulus of the particle material. Numerical simulations using the discrete element method (DEM) were performed to confirm the behavior of the elastomer particles when they were packed in both chambers. The compressive force distribution and velocity vector diagram of particles in the simulations showed that friction and compression between particles due to particle movement, friction between particles and the chamber walls, and the viscosity of the elastomer particles caused a large hysteresis in the damper force. The maximum damper force is affected by the viscoelastic component force and the friction force in the same proportion, and the hysteresis is dominated by the friction force. The simulation results were confirmed to be in good agreement, both qualitatively and quantitatively, with the experimentally measured damper force characteristics.
Design and Analysis of a Programmable Rotational Element Utilizing Coupled Kresling Origami Modules
Authors: Li Zhen , Kidambi Narayanan , Wang Liangmo , Wang Kon-Well
Published: November 2020

Origami–inspired designs are being explored extensively for structural and material applications in a variety of different engineering fields because of their attractive kinematic and mechanical properties, design flexibility, and multi-functionality. However, most if not all of these studies have focused on translational motions. Utilizing origami in replacing or enhancing torsional components, such as joints, shafts and motors, has received little attention. With this in mind, this research introduces an origami-inspired rotational element via a coupled Kresling modular design (CKMD). Two Kresling origami modules with opposite chirality are integrated, achieving pure rotational motion between two ends of polygon surfaces. A model with nondimensionalized parameters is developed and a key design variable (natural height ratio) is varied to investigate the kinematic and mechanical properties of CKMD. Results show that these properties can be tailored by strategic selection of the natural height ratio, which alters the energy landscapes of both Kresling modules and leads to qualitatively distinct mechanical responses. Further investigation shows that the rotational stability characteristics of CKMD — monostability, symmetric and asymmetric bistability — may be programmed in a similar manner. Design guidelines are discussed, and the outcomes lay the foundation for integrating programmable, origami-inspired, rotational components in mechanical systems.
Wave Propagation in a Network of Buckled Beams Directly and Parametrically Excited at One End
Authors: Talebi Bidhendi M. Reza
Published: November 2020

Wave propagation in a network of buckled beams, which represents a finite dissipative periodic structure with quadratic and cubic nonlinearities, is studied. The aforementioned structure is harmonically driven externally and parametrically at one end with forcing frequencies lying within its stop band, one above and one below. Numerical calculations show the occurrence of supratransmission, a sudden increase in the energy transmitted across the finite structure, after a certain forcing amplitude of the external excitation. In essence, this nonlinear wave propagation mechanism for the discrete nonlinear periodic structure occurs due to loss of stability of the periodic solutions that are initially localized to the driven end of the structure (nonlinear instability). It is found that small parametric excitation can considerably decrease the required threshold for the onset of energy transmission within the stop band.
On Periodic Motions in a Periodically Driven van der Pol-Duffing Oscillator
Authors: Xu Yeyin , Luo Albert C. J.
Published: November 2020

In this paper, the symmetric and asymmetric period-1 motions on the bifurcation tree are obtained for a periodically driven van der Pol-Duffing hardening oscillator through a semi-analytical method. Such a semi-analytical method develops an implicit mapping with prescribed accuracy. Based on the implicit mapping, the mapping structures are used to determine periodic motions in the van der Pol-Duffing oscillator. The symmetry breaks of period-1 motion are determined through saddle-node bifurcations, and the corresponding asymmetric period-1 motions are generated. The bifurcation and stability of period-1 motions are determined through eigenvalue analysis. To verify the semi-analytical solutions, numerical simulations are also carried out.
Predicting Build Orientation of Additively Manufactured Parts With Mechanical Machining Features Using Deep Learning
Authors: Eranpurwala Aliakbar , Ghiasian Seyedeh Elaheh , Lewis Kemper
Published: November 2020

Additive Manufacturing (AM) is a revolutionary development that is being viewed as a core technology for fabricating current and future engineered products. While AM has many advantages over subtractive manufacturing processes, one of the primary limitations of AM is to swiftly evaluate precise part build orientations. Current algorithms are either computationally expensive or provide multiple alternative orientations, requiring additional decision tradeoffs. To hasten the process of finding accurate part build orientation, a data-driven predictive model is introduced by mapping standard machining features to build orientation angles. A combinatory learning algorithm of classification and regression is utilized for the prediction of build orientation. The framework uses 54,000 voxelized standard tessellated language (STL) files as input to train the classification algorithm for eighteen standard machining features using a nine-layer 3D Convolutional Neural Network (CNN). Additionally, a multi-machining feature dataset of 1000 voxelized STL files are evaluated in parallel by performing quaternion rotations to obtain build orientation angles based on minimization of support structure volume. A regression model is then developed to establish a relationship between the machining features and orientation angles to predict optimal build orientation for new parts.
An Initial Guess Free Method for Least Squares Parameter Estimation in Nonlinear Models
Authors: Zhang Guanglu , Allaire Douglas , Cagan Jonathan
Published: November 2020

Fitting models to data is critical in many science and engineering fields. A major task in fitting models to data is to estimate the value of each parameter in a given model. Iterative methods, such as the Gauss-Newton method and the Levenberg-Marquardt method, are often employed for parameter estimation in nonlinear models. However, practitioners must guess the initial value for each parameter in order to initialize these iterative methods. A poor initial guess can contribute to non-convergence of these methods or lead these methods to converge to a wrong solution. In this paper, an initial guess free method is introduced to find the optimal parameter estimators in a nonlinear model that minimizes the squared error of the fit. The method includes three algorithms that require different level of computational power to find the optimal parameter estimators. The method constructs a solution interval for each parameter in the model. These solution intervals significantly reduce the search space for optimal parameter estimators. The method also provides an empirical probability distribution for each parameter, which is valuable for parameter uncertainty assessment. The initial guess free method is validated through a case study in which Fick’s second law is fit to an experimental data set. This case study shows that the initial guess free method can find the optimal parameter estimators efficiently. A four-step procedure for implementing the initial guess free method in practice is also outlined.
Investigation of 3:1 Internal Resonance of Electrostatically Actuated Microbeams With Flexible Supports
Authors: Kumar Praveen , Inamdar Mandar M. , Pawaskar Dnyanesh N.
Published: November 2020

Interaction between modes due to internal resonance has many applications in MEMS devices. In this paper, we investigate the modal interaction through 3 : 1 internal resonance of an electrostatically actuated microbeam with flexible supports in the form of rotational and transversal springs. The static displacement and the first three modal frequencies are obtained at the applied DC voltage by a reduced order model for a specified ratio of electrode gap and thickness. We then obtain the value of applied voltage for which 3 : 1 internal resonance exists for four different combinations of unequal end support stiffnesses. We calculate the coefficients of the coupled dynamical equations of first two modes for all the four cases and solve them by using numerical time integration and the method of multiple scales. We observe the interaction between the first and the second mode when each of the modes is independently excited by an external source. When the second mode is externally excited, interestingly, we also find that the undriven mode response amplitude is twice that of the driven mode.
Identification of Rider’s Arms Dynamic Response and Effects on Bicycle Stability
Authors: Doria Alberto , Marconi Edoardo , Massaro Matteo
Published: November 2020

It is known that the way a bicycle or motorcycle rider grasps the handlebar may have implications on the bike stability. Indeed, the rider closes a loop (with his/her hands) between the front assembly and the chassis of the bike, which in turn affects the open-loop stability of the vehicle. The aim of this paper is to experimentally quantify the interaction between the rider and the handlebar through the frequency response function (FRF), and to numerically simulate the effects of such interaction on the bicycle stability. In order to implement the effect of rider’s arms/hands, a mechanical model is employed to fit the experimental FRFs. The parameters of a number of different riders have been derived and used to assess the effect on bike dynamics.
Kinematic Design of Functional Nanoscale Mechanisms From Molecular Primitives
Authors: Tavousi Pouya , Chorsi Meysam T. , Mundrane Caitlyn , Gorbatyuk Vitaliy , Kazerounian Kazem , Ilies Horea
Published: November 2020

Natural nanomechanisms such as capillaries, neurotransmitters, and ion channels play a vital role in the living systems. But the design principles developed by nature through evolution are not well understood and, hence, not applicable to engineered nanomachines. Thus, the design of nanoscale mechanisms with prescribed functions remains a challenge. Here, we present a systematic approach based on established kinematics techniques to designing, analyzing, and controlling manufacturable nanomachines with prescribed mobility and function built from a finite but extendable number of available “molecular primitives.” Our framework allows the systematic exploration of the design space of irreducibly simple nanomachines, built with prescribed motion specification by combining available nanocomponents into systems having constrained, and consequently controllable motions. We show that the proposed framework has allowed us to discover and verify a molecule in the form of a seven link, seven revolute (7R) close loop spatial linkage with mobility (degree of freedom) of one. Furthermore, our experiments exhibit the type and range of motion predicted by our simulations. Enhancing such a structure into functional nanomechanisms by exploiting and controlling their motions individually or as part of an ensemble could galvanize development of the multitude of engineering, scientific, medical, and consumer applications that can benefit from engineered nanomachines.