bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of the regional bioarchitecture in the human aorta
Authors: Concannon J. , Dockery P. , Black A. , Sultan S. , Hynes N. , McHugh P. E. , Moerman K. M. , McGarry J. P.
Published: September 2019

Regional variance in human aortic bioarchitecture responsible for the elasticity of the vessel is poorly understood. The current study quantifies the elements responsible for aortic compliance, namely, elastin, collagen and smooth muscle cells, using histological and stereological techniques on human tissue with a focus on regional heterogeneity. Using donated cadaveric tissue, a series of samples were excised between the proximal ascending aorta and the distal abdominal aorta, for five cadavers, each of which underwent various staining procedures to enhance specific constituents of the wall. Using polarised light microscopy techniques, the orientation of collagen fibres was studied for each location and each tunical layer of the aorta. Significant transmural and longitudinal heterogeneity in collagen fibre orientations were uncovered throughout the vessel. It is shown that a von Mises mixture model is required accurately to fit the complex collagen fibre distributions that exist along the aorta. Additionally, collagen and smooth muscle cell density was observed to increase with increasing distance from the heart, whereas elastin density decreased. Evidence clearly demonstrates that the aorta is a highly heterogeneous vessel which cannot be simplistically represented by a single compliance value. The quantification and fitting of the regional aortic bioarchitectural data, although not without its limitations, including mean cohort age of 77.6 years, facilitates the development of next‐generation finite element models that can potentially simulate the influence of regional aortic composition and microstructure on vessel biomechanics.
Human placental villi contain stromal macrovesicles associated with networks of stellate cells
Authors: Palaiologou E. , Etter O. , Goggin P. , Chatelet D. S. , Johnston D. A. , Lofthouse E. M. , Doherty R. , Pearson‐Farr J. , Sengers B. G. , Torrens C. , Cleal J. K. , Page A. M. , Lewis R. M.
Published: September 2019

Placental function is essential for fetal development and establishing the foundations for lifelong health. The placental villous stroma is a connective tissue layer that supports the fetal capillaries and villous trophoblast. All the nutrients that cross the placenta must also cross the stroma, and yet little is known about this region. This study uses high‐resolution three‐dimensional imaging to explore the structural complexity of this region within the placental villi. Serial block‐face scanning electron microscopy and confocal microscopy were used to image the placental villous stroma in three‐dimensions. Transmission electron microscopy (TEM) was used to generate high resolution two‐dimensional images. Stereological approaches were used to quantify volumes of stromal constituents. Three‐dimensional imaging identified stromal extracellular vesicles, which constituted 3.9% of the villous stromal volume. These stromal extracellular vesicles were ovoid in shape, had a median length of 2750 nm (range 350–7730 nm) and TEM imaging confirmed that they were bounded by a lipid bilayer. Fifty‐nine per cent of extracellular vesicles were in contact with a fibroblast‐like stellate cell and these vesicles were significantly larger than those where no contact was observed. These stellate cells formed local networks with adherent junctions observed at contact points. This study demonstrates that the villous stroma contains extracellular macrovesicles which are considerably larger than any previously described in tissue or plasma. The size and abundance of these macrovesicles in the villous stroma highlight the diversity of extracellular vesicle biology and their roles within connective tissues.
Gut feeling: A grounded theory study to identify clinical educators' reasoning processes in putting students on a learning contract
Authors: El Hussein Mohamed Toufic , Fast Olive
Published: September 2019

Aim

To develop a substantive theoretical explanation that makes sense of the decision‐making process that clinical instructors use to place students on a learning contract.

Background

Clinical instructors are challenged with the task of objectively evaluating students using subjective tools such as anecdotal notes, diaries, unstructured observations and verbal feedback from other nurses. Clinical instructors' assessment decisions have a considerable impact on a variety of key stakeholders, not least of all students.

Design

Grounded theory method and its heuristic tools including the logic of constant comparison, continuous memoing and theoretical sampling to serve conceptualisation were used in the process of data collection and analysis.

Methods

Seventeen individual semi‐structured interviews with clinical instructors in one university in Western Canada were conducted between May 2016–May 2017. Data were analysed using open, axial and selective coding consistent with grounded theory methodology. The study was checked for the Standards for Reporting Qualitative Research (SRQR) criteria (See Appendix S1).

Findings

Three subcategories, “brewing trouble,” “unpacking thinking” and “benchmarking” led to the study's substantive theoretical explanation. “Gut feeling” demonstrates how clinical instructors reason in their decision‐making process to place a student on a learning contract.

Conclusion

Placing a student on a learning contract is impacted by personal, professional and institutional variables that together shift the process of evaluation towards subjectivity, thus influencing students' competency. A system‐level approach, focusing on positive change through implementing innovative assessment strategies, such as using a smart phone application, is needed to provide some degree of consistency and objectivity.

Relevance to clinical practice

Making visible the objective assessments currently being done by clinical instructors has the potential to change organisational standards, which in turn impact patient and clinical outcomes.
Barriers and facilitators involved in standardised care plan individualisation process in acute hospitalisation wards: A grounded theory approach
Authors: Castellà‐Creus Mònica , Delgado‐Hito Pilar , Casanovas‐Cuellar Cristina , Tàpia‐Pérez Marta , Juvé‐Udina Maria‐Eulàlia
Published: September 2019

Objective

To identify and classify the barriers and facilitators of the individualisation process of the standardised care plan in hospitalisation wards.

Background

The administration of individualised care is one of the features of the nursing process. Care plans are the structured record of the diagnosis, planning and evaluation stages of the nursing process. Although the creation of standardised care plan has made recording easier, it is still necessary to record the individualisation of the care. It is important to study the elements that influence the individualisation process from the nurses' perspective.

Design

Qualitative study with the grounded theory approach developed by Strauss and Corbin.

Methods

Thirty‐nine nurses from three hospitals participated by way of theoretical sampling. In‐depth interviews were conducted, as well as participant observation, document analysis and focus group discussion. The analysis consisted of open, axial and selective coding until data saturation was reached. EQUATOR guidelines for qualitative research (COREQ) were applied.

Results

For both barriers and facilitators, three thematic categories emerged related to organisational, professional and individual aspects. The identified barriers included routines acquired in the wards, the tradition of narrative records, lack of knowledge and limited interest in individualisation. The identified facilitators included holding clinical care sessions, use of standardised care plan and an interface terminology, the nurse's expertise and willingness to individualise.

Conclusion

The individualisation process of the standardised care plan involves multiple barriers and facilitators, which influence its degree of accuracy.

Relevance to clinical practice

Implementing strategies at an organisational level, professional level and individual level to improve the way the process is carried out would encourage individualising the standardised care plan in a manner that is consistent with the needs of the patient and family; it would improve the quality of care and patient satisfaction.
Seascape genetics of the stalked kelp Pterygophora californica and comparative population genetics in the Santa Barbara Channel
Authors: Hargarten Heidi L. , Johansson Mattias L. , Reed Daniel C. , Coelho Nelson C. , Siegel David A. , Alberto Filipe
Published: September 2019

We conducted a population genetic analysis of the stalked kelp, Pterygophora californica, in the Santa Barbara Channel, California, USA. The results were compared with previous work on the genetic differentiation of giant kelp, Macrocystis pyrifera, in the same region. These two sympatric kelps not only share many life history and dispersal characteristics but also differ in that dislodged P. californica does not produce floating rafts with buoyant fertile sporophytes, commonly observed for M. pyrifera. We used a comparative population genetic approach with these two species to test the hypothesis that the ability to produce floating rafts increases the genetic connectivity among kelp patches in the Santa Barbara Channel. We quantified the association of habitat continuity and oceanographic distance with the genetic differentiation observed in stalked kelp, like previously conducted for giant kelp. We compared both overall (across all patches) and pairwise (between patches) genetic differentiation. We found that oceanographic transit time, habitat continuity, and geographic distance were all associated with genetic connectivity in P. californica, supporting similar previous findings for M. pyrifera. Controlling for differences in heterozygosity between kelp species using Jost's DEST, we showed that global differentiation and pairwise differentiation were similar among patches between the two kelp species, indicating that they have similar dispersal capabilities despite their differences in rafting ability. These results suggest that rafting sporophytes do not play a significant role in effective dispersal of M. pyrifera at ecologically relevant spatial and temporal scales.
The Impact of a Modified Initial Teacher Education on Challenging Trainees' Understanding of Neuromyths
Authors: McMahon Kendra , Yeh Chloe Shu‐Hua , Etchells Peter J.
Published: September 2019

Initial teacher education (ITE) offers an underutilized opportunity for bridging the gap between neuroscience research and educational practice. This article reports on innovations embedded within an ITE program to support trainee teachers to recognize and challenge the persistence of neuromyths. Education researchers, neuroscientists, and psychologists collaboratively applied design‐based research to create, improve, and reflect on original neuroeducational teaching/learning resources for university‐based primary (elementary) ITE trainees. Encouragingly, pre and postsurveys showed reductions in trainees' beliefs in neuromyths and a shift to responses showing uncertainty that suggested their beliefs became unsettled. The most persistent neuromyths were those regarding fish oils, left brain/right brain, and learning styles/visual, auditory, or kinaesthetic (VAK). Trainees retained their initial interest in knowledge about the brain and education, gained confidence, and became more critical about applying the learning sciences in educational contexts.
Fusaric acid instigates the invasion of banana by Fusarium oxysporum f. sp. cubense TR4
Authors: Liu Siwen , Li Jian , Zhang Yong , Liu Na , Viljoen Altus , Mostert Diane , Zuo Cunwu , Hu Chunhua , Bi Fangcheng , Gao Huijun , Sheng Ou , Deng Guiming , Yang Qiaosong , Dong Tao , Dou Tongxin , Yi Ganjun , Ma Li‐Jun , Li Chunyu
Published: September 2019

Fusaric acid (FSA) is a phytotoxin produced by several Fusarium species and has been associated with plant disease development, although its role is still not well understood.

Mutation of key genes in the FSA biosynthetic gene (FUB) cluster in Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) reduced the FSA production, and resulted in decreased disease symptoms and reduced fungal biomass in the host banana plants.

When pretreated with FSA, both banana leaves and pseudostems exhibited increased sensitivity to Foc TR4 invasion. Banana embryogenic cell suspensions (ECSs) treated with FSA exhibited a lower rate of O2 uptake, loss of mitochondrial membrane potential, increased reactive oxygen species (ROS) accumulation, and greater nuclear condensation and cell death. Consistently, transcriptomic analysis of FSA‐treated ECSs showed that FSA may induce plant cell death through regulating the expression of genes involved in mitochondrial functions.

The results herein demonstrated that the FSA from Foc TR4 functions as a positive virulence factor and acts at the early stage of the disease development before the appearance of the fungal hyphae in the infected tissues.
Photoexcited CRY1 and phyB interact directly with ARF6 and ARF8 to regulate their DNA‐binding activity and auxin‐induced hypocotyl elongation in Arabidopsis
Authors: Mao Zhilei , He Shengbo , Xu Feng , Wei Xuxu , Jiang Lu , Liu Yao , Wang Wenxiu , Li Ting , Xu Pengbo , Du Shasha , Li Ling , Lian Hongli , Guo Tongtong , Yang Hong‐Quan
Published: September 2019

Arabidopsis CRY1 and phyB are the primary blue and red light photoreceptors mediating blue and red light inhibition of hypocotyl elongation, respectively. Auxin is a pivotal phytohormone involved in promoting hypocotyl elongation. CRY1 and phyB interact with and stabilize auxin/indole acetic acid proteins (Aux/IAAs) to inhibit auxin signaling. The present study investigated whether photoreceptors might interact directly with Auxin Response Factors (ARFs) to regulate auxin signaling.

Protein–protein interaction studies demonstrated that CRY1 and phyB interact physically with ARF6 and ARF8 through their N‐terminal domains in a blue and red light‐dependent manner, respectively. Moreover, the N‐terminal DNA‐binding domain of ARF6 and ARF8 is involved in mediating their interactions with CRY1.

Genetic studies showed that ARF6 and ARF8 act partially downstream from CRY1 and PHYB to regulate hypocotyl elongation under blue and red light, respectively. Chromatin immunoprecipitation‐PCR assays demonstrated that CRY1 and phyB mediate blue and red light repression of the DNA‐binding activity of ARF6 and ARF6‐target gene expression, respectively.

Altogether, the results herein suggest that the direct repression of auxin‐responsive gene expression mediated by the interactions of CRY1 and phyB with ARFs constitutes a new layer of the regulatory mechanisms by which light inhibits auxin‐induced hypocotyl elongation.
Three‐dimensional comparison of the skeletal and dentoalveolar effects of the Herbst and Pendulum appliances followed by fixed appliances: A CBCT study
Authors: Taylor Kyle L. , Evangelista Karine , Muniz Luciana , Ruellas Antônio Carlos de Oliveira , Valladares‐Neto José , McNamara James , Franchi Lorenzo , Kim‐Berman Hera , Cevidanes Lucia Helena Soares
Published: September 2019

Objectives

To compare three‐dimensional (3D) skeletal and dentoalveolar effects of the Herbst and Pendulum appliances followed by fixed orthodontic treatment in growing patients.

Setting and sample population

A sample of 35 adolescents with cone‐beam computed tomography scans obtained prior to Herbst and Pendulum treatment (T1) and immediately after fixed appliance treatment (T2).

Materials and Methods

Patients with Class II malocclusion was assessed retrospectively and divided into two treatment groups: Herbst group (n = 17, age: 12.0 ± 1.6 years) and Pendulum group (n = 18, age: 12.1 ± 1.5 years), with a mean treatment duration of 2.8 ± 0.8 years and 2.5 ± 0.7 years, respectively. Reconstructions of the maxillomandibular and dentoalveolar regions and data in 3D were obtained relative to cranial base, maxillary and mandibular regional superimpositions. Treatment outcomes (T2‐T1) were compared between both groups using t tests for independent samples (P<.05).

Results

Significant increase in mandibular length was observed in the Herbst group (7.3 ± 3.5 mm) relative to the Pendulum group (4.6 ± 4.5 mm). Inferior and anterior displacements of Pogonion were 2.2 mm and 1.6 mm greater in the Herbst group, respectively. The mesial displacement of the lower first molars was significantly greater in the Herbst group (1.9 mm). The upper first molars had contrasting results in sagittal displacement, with 0.6 ± 1.7 mm of distal displacement with the Pendulum and 1.4 ± 2.1 mm of mesial displacement with the Herbst. Lower incisor projection and proclination were similar between groups.

Conclusions

The Herbst and Pendulum appliances followed by comprehensive orthodontic treatment effectively corrected Class II malocclusion in growing patients, but with differing skeletal and dentoalveolar effects.
Saliva microbiome in primary Sjögren’s syndrome reveals distinct set of disease‐associated microbes
Authors: Sharma Disha , Sandhya Pulukool , Vellarikkal Shamsudheen Karuthedath , Surin Ajit Kumar , Jayarajan Rijith , Verma Ankit , Kumar Anoop , Ravi Rowmika , Danda Debashish , Sivasubbu Sridhar , Scaria Vinod
Published: September 2019

Objective

This study systematically aims to evaluate the salivary microbiome in patients with primary Sjögren's syndrome (pSS) using 16S rRNA sequencing approach.

Methods

DNA isolation and 16S rRNA sequencing was performed on saliva of 37 pSS and 35 control (CC) samples on HiSeq 2500 platform. 16S rRNA sequence analysis was performed independently using two popular computational pipelines, QIIME and less operational taxonomic units scripts (LoTuS).

Results

There were no significant changes in the alpha diversity between saliva of patients and controls. However, four genera including Bifidobacterium, Lactobacillus, Dialister and Leptotrichia were found to be differential between the two sets, and common between both QIIME and LoTuS analysis pipelines (Fold change of 2 and p < .05). Bifidobacterium, Dialister and Lactobacillus were found to be enriched, while Leptotrichia was significantly depleted in pSS compared to the controls. Exploration of microbial diversity measures (Chao1, observed species and Shannon index) revealed a significant increase in the diversity in patients with renal tubular acidosis. An opposite trend was noted, with depletion of diversity in patients with steroids.

Conclusion

Our analysis suggests that while no significant changes in the diversity of the salivary microbiome could be observed in Sjögren's syndrome compared to the controls, a set of four genera were significantly and consistently differential in the saliva of patients with pSS. Additionally, a difference in alpha diversity in patients with renal tubular acidosis and those on steroids was observed.
Root coverage using a dual layer type I non‐cross‐link collagen haemostatic biomaterial – a 10 year follow‐up
Authors: de Abreu F.A.M. , Zenóbio E.G.
Published: September 2019

Aesthetics and predictability, such as long‐term function, shape, texture, colour and contour of the tissues are important factors in root coverage procedures. Surgical procedures could be recommended to treat gingival recession; for example, the use of collagen membrane stands out among them. This case report shows the clinical efficiency of a dual layer collagen membrane associated with coronal flap displacement to treat a MILLER class II gingival recession on the mandibular right first premolar. The patient had lack of keratinised tissue, accumulation of bacterial biofilm and exposed dental root, creating aesthetic disharmony. The periodontal parameters of probing depth, clinical attachment loss level, recession and width of the keratinised gingiva on the mid‐buccal site were measured at baseline, 120 days, 5 and 10 years post‐surgery. Complete coverage with high, long term stability was obtained. The present study shows that a dual layer membrane could be considered as an option to treat gingival recessions.
A multidimensional examination of marital conflict and subjective health over 16 years
Authors: Shrout M. Rosie , Brown Randal D. , Orbuch Terri L. , Weigel Daniel J.
Published: September 2019

Guided by stress process perspectives, this study conceptualizes marital conflict as a multidimensional stressor to assess how three aspects of conflict—frequency of disagreements, breadth of disagreements, and cumulative disagreements—impact subjective health. Longitudinal data of married couples spanning 16 years (n = 373 couples) were analyzed using multilevel modeling. For husbands, more frequent disagreements than usual within a given year were associated with poorer subjective health. For wives, the greater cumulative effects of disagreements over 16 years were harmful for subjective health. We discuss how gendered self‐representations and relationship power issues help explain the findings. This research demonstrated the importance of examining multiple aspects of marital conflict to reveal that their subjective health consequences function differently for wives and husbands.
Good Workers and Crooked Bosses: The Effect of Voice Suppression by Supervisors on Employees’ Populist Attitudes and Voting
Authors: Stanojevic Antonia , Akkerman Agnes , Manevska Katerina
Published: September 2019

This study is the first to explore the effect of political socialization in the workplace on populist attitudes. We investigate the effect of workplace voice suppression on employees' populist attitudes and voting. We expect employees who were suppressed by supervisors to hold more populist attitudes and to be more likely to vote for a populist party than employees who were not. We argue that some employees experience voice suppression by supervisors as stressful, so splitting is likely to be employed as a defense mechanism. Splitting is achieved through cognitive distinction and antagonism between “the good workers” and “the crooked bosses.” Such a split mental framework can generalize into a worldview that contrasts “the pure people” and “the corrupt elite,” a core characteristic of populism. We predict that the extent to which suppression triggers splitting and consequentially incites populist attitudes and voting depends on employees' acceptance of power distance. We test our hypotheses using SEM on survey data from 2990 members of the Dutch labor force. Our results show that experiences of voice suppression are positively related to populist attitudes and populist voting. As expected, this effect is stronger for employees who are less accepting of power distance.
Dissonant endings of chord progressions elicit a larger ERAN than ambiguous endings in musicians
Authors: Pagès‐Portabella Carlota , Toro Juan M.
Published: September 2019

In major‐minor tonal music, the hierarchical relationships and patterns of tension/release are essential for its composition and experience. For most listeners, tension leads to an expectation of resolution. Thus, when musical expectations are broken, they are usually perceived as erroneous and elicit specific neural responses such as the early right anterior negativity (ERAN). In the present study, we explored if different degrees of musical violations are processed differently after long‐term musical training in comparison to day‐to‐day exposure. We registered the ERPs elicited by listening to unexpected chords in both musicians and nonmusicians. More specifically, we compared the responses of strong violations by unexpected dissonant endings and mild violations by unexpected but consonant endings (Neapolitan chords). Our results show that, irrespective of training, irregular endings elicited the ERAN. However, the ERAN for dissonant endings was larger in musicians than in nonmusicians. More importantly, we observed a modulation of the neural responses by the degree of violation only in musicians. In this group, the amplitude of the ERAN was larger for strong than for mild violations. These results suggest an early sensitivity of musicians to dissonance, which is processed as less expected than tonal irregularities. We also found that irregular endings elicited a P3 only in musicians. Our study suggests that, even though violations of harmonic expectancies are detected by all listeners, musical training modulates how different violations of the musical context are processed.
The challenge of large litters on the immune system of the sow and the piglets
Authors: Oliviero Claudio , Junnikkala Sami , Peltoniemi Olli
Published: September 2019

The use of hyperprolific sow lines has increased litter size considerably in the last three decades. Nowadays, in some countries litters can reach up to 18–20 piglets being a major challenge for the sow's physiology during pregnancy, parturition and lactation. The increased number of piglets born per litter prolongs sensibly the duration of farrowing, decreases the piglets’ average weight at birth and their vitality, increases the competition for colostrum intake and can affect negatively piglets’ survival. This review aims to describe how large litters can affect the immune system of the sow and the piglets and proposes measures to improve this condition.
Air‐liquid interface cell culture: From airway epithelium to the female reproductive tract
Authors: Chen Shuai , Schoen Jennifer
Published: September 2019

The air‐liquid interface (ALI) approach is primarily used to mimic respiratory tract epithelia in vitro. It is also known to support excellent differentiation of 3D multilayered skin models. To establish an ALI culture, epithelial cells are seeded into compartmentalized culture systems on porous filter supports or gel substrata. After an initial propagation period, the culture medium is removed from the apical side of the epithelium, exposing the cells to the surrounding air. Therefore, nutritive supply to the cells is warranted only by the basolateral cell pole. Under these conditions, the epithelial cells differentiate and regain full baso‐apical polarity. Some types of epithelia even generate in vivo‐like apical fluid or mucus. Interestingly, the ALI culture approach has also been shown to support morphological and functional differentiation of epithelial cells that are not normally exposed to ambient air in vivo. This review aims at giving a brief overview on the characteristics of ALI cultures in general and ALI models of female reproductive tract epithelia in particular. We discuss the applicability of ALI models for the investigation of the early embryonic microenvironment and for its implications in assisted reproductive technologies.
Disability at the intersections
Authors: Shifrer Dara , Frederick Angela
Published: September 2019

Complete and accurate understandings of stratification depend on more regular consideration of disability. To build sociologists' recognition of disability as a socially constructed axis of stratification, we first demonstrate the construction of the disability category through classic legitimating processes: moral attributions, biological attributions, separation, and dichotomization. Expanding understandings of basic processes of stratification, we then document the centrality of disability in the social construction of class, race, gender, sexual orientation, and age. Finally, we show various ways disability functions as an axis of stratification in intersection with other key axes of stratification.
Graying of U.S. Bankruptcy: Fallout from Life in a Risk Society
Authors: Thorne Deborah , Foohey Pamela , Lawless Robert M. , Porter Katherine
Published: September 2019

As neoliberal ideology and policies gained a foothold in the early 1980s, the social safety net for older Americans contracted. Responsibility for the risks associated with aging, namely retirement income and healthcare costs, was increasingly transferred from the state to the individual. Using data from the Consumer Bankruptcy Project, we report that since 1991, there has been more than a twofold increase in the rate at which older Americans (age 65 and over) file for consumer bankruptcy and an almost fivefold increase in the percentage of older persons in the U.S. bankruptcy system. This magnitude of growth is so large that the broader trend of an aging U.S. population can explain only a small portion of the effect. Respondents report that inadequate income and unmanageable healthcare costs are the chief reasons for their bankruptcies. Our findings suggest that neoliberal policies that offload healthcare costs and retirement savings onto older Americans may facilitate their bankruptcy filings.
The removal of butachlor from soil by wastewater‐derived Rhodopseudomonas marshes
Authors: Wu Pan , Xie Liying , Li Jirong , Yang Weiguang , Han Ziqiao , Wu Xiaozhen , Mo Wentao , Wen Cheng , Gao Yang , Wan Tian , Zhang Ying
Published: September 2019

Butachlor is a systemic selective pre‐emergent herbicide most commonly used to control grasses and broadleaf weeds. Residual butachlor in soil can have harmful ecotoxological effects and remediation is, therefore, important. Effects of Rhodopseudomonas marshes in wastewater effluent on biorestoration of butachlor in soil were investigated. Over a time period of one day, butachlor induced EthB gene expression to synthesize cytochrome P450 monooxygenase which led to the successful bioremediation of the herbicide. Residual organics in wastewater effluent provided sufficient carbon sources for continued growth of R. marshes beyond one day.
Cytologic identification of fungal arthritis in a Labrador Retriever with disseminated Talaromyces helicus infection
Authors: Whipple Kellie M. , Shmalberg Justin W. , Joyce Ashley C. , Beatty Sarah S.
Published: September 2019

An 8‐year‐old, neutered male Labrador Retriever presented with acute forelimb lameness. Clinical signs progressed over one week. On physical examination, right cubital joint effusion and bilateral axillary lymphadenomegaly were noted, and severe internal lymphadenomegaly was observed ultrasonographically. Granulomatous lymphadenitis with intralesional fungi was noted cytologically, and the dog was ultimately diagnosed with disseminated Talaromyces helicus infection via PCR of a pure isolate. Extensive medical therapy was pursued, and months later, an arthrocentesis was performed due to continued lameness and severe cubital joint effusion. The synovial fluid contained increased numbers of neutrophils, macrophages, and multinucleated giant cells. Frequent fungal hyphae were found both intracellularly and extracellularly. These basophilic organisms were 2‐4 µm in width with internal eosinophilic granules, roughly parallel walls, and occasional to frequent septa. Round to oval yeast‐like forms with thin, clear halos were also occasionally identified. Due to the severity of clinical signs, the right thoracic limb was amputated. Histologic examination of the cubital joint revealed marked granulomatous synovitis, fasciitis, panniculitis, and osteomyelitis, all with intralesional fungi. Talaromyces helicus is a very rare cause of disease, reported only in one other dog. Granulomatous lymphadenitis appears to be a feature of this disease, but this report is the first to describe a significant synovial component.
Synovial butorphanol concentrations and mechanical nociceptive thresholds after intravenous regional limb perfusion in standing sedated horses
Authors: Crabtree Naomi E. , Mochal‐King Cathleen A. , Sloan Pearce B. , Eddy Alison L. , Wills Robert W. , Meredith Ashley N. , Fontenot Robin L.
Published: September 2019

Objective

To determine synovial butorphanol concentrations and mechanical nociceptive threshold (MNT) changes after butorphanol intravenous regional limb perfusion (IVRLP).

Study design

Experimental

Animals

Six adult horses.

Methods

Cephalic IVRLP was performed with 10 mg butorphanol in sedated horses with a wide rubber tourniquet and a total volume of 30 mL. Radiocarpal synovial fluid and serum concentrations along with MNT were evaluated prior to and 0.5, 1, 2, 4, and 6 hours after IVRLP. Butorphanol concentrations were determined with liquid chromatography coupled to tandem mass spectrometry positive electrospray ionization.

Results

Butorphanol concentrations reached mean (SD) peak concentrations of 9.47 ng/mL (±12.00) in synovial fluid and 3.89 ng/mL (3.29) in serum 30 minutes after IVRLP. Concentrations remained above baseline for 4 hours in synovial fluid (P ≤ .017) and for 2 hours in serum (P ≤ .016). The only difference in MNT was detected 1 hour after IVRLP, when MNT were higher in controls than in treated horses (P = .047).

Conclusion

Butorphanol IVRLP seemed well tolerated and resulted in measurable levels of butorphanol in the radiocarpal synovial fluid of five of six horses.

Clinical significance

Intravenous regional limb perfusion appears to be a viable alternative to administer butorphanol, but additional investigation is required to evaluate the dose and local concentrations required for analgesia.
An investigation of Salmonella Fluntern illnesses linked to leopard geckos—United States, 2018
Authors: Koski Lia , DeBess Emilio , Rosen Hilary E. , Reporter Roshan , Waltz Thomas , Leeper Molly , Concepcion Acevedo Jeniffer , Karpíšková Renáta , McCormick Jacquelyn , Gelbicova Tereza , Morningstar-Shaw Brenda , Nichols Megin , Leman Richard F.
Published: September 2019

Reptile contact can result in zoonotic non‐typhoidal salmonellosis. In April 2018, Oregon Public Health Division contacted CDC about a cluster of four Salmonella serovar Fluntern (SF) illnesses in four states (OR, CA, IA, NY); patients reported contact with geckos, a popular reptile pet. PulseNet, the national molecular subtyping network of food‐borne disease surveillance, subsequently identified additional SF clinical isolates. Twelve cases in 11 states were identified; median age was 5 years (range: <1–58 years). Three patients were hospitalized; no deaths were reported. Of those with exposure information (n = 10), all reported reptile exposure; 9 (90%) specified contact with leopard geckos. No common source of geckos was identified from reported purchase locations. Los Angeles County (LAC) health officials isolated SF from one patient's leopard gecko. Five reptile/gecko isolates were identified from the USDA National Veterinary Services Laboratories (NVSL) from 2015 to 2018. Five countries responded to an Epidemic Intelligence Information System post by PulseNet; reptile isolate sequence data were received from Czech Republic. A clinical case from England was identified through the National Center for Biotechnology Information pathogen detection pipeline; the patient did not report contact with leopard geckos. Whole genome sequencing analysis revealed substantial genetic diversity between clinical and animal isolates; however, gecko and clinical isolates from LAC were highly related (1 allele difference). This investigation linking SF illnesses to leopard geckos highlights an important public health risk from pets. A better understanding of how geckos are distributed by the pet industry in the United States could improve traceability to points of origin and mitigate Salmonella transmission at gecko breeders. Earlier NVSL reports of SF isolates from geckos suggest the risk of human SF infection from geckos is not new. This investigation demonstrates a need to educate gecko breeders, retailers and gecko owners about the continued Salmonella infection risk from pet geckos.
Optimizing a New Configuration of a Proton Exchange Membrane Fuel Cell Cycle With Burner and Reformer Through a Particle Swarm Optimization Algorithm for Residential Applications
Authors: Yousefi Mehdi , Ehyaei M. A. , Rosen Marc A.
Published: September 2019

The energy, exergy, and economic aspects are analyzed of a cycle consisting of a polymer fuel cell, a burner, a reformer, and a heat exchanger. Water is used for cooling the fuel cell, and the heated water is used for domestic consumption. The exergy and energy efficiencies of the cycle are calculated, and the effects of various cycle parameters on the exergy and energy efficiencies are investigated. To maximize the exergy efficiency while minimizing the cost of electricity generation by the fuel cell, the particle swarm optimization (PSO) algorithm is utilized. The results show that increasing the cooling water flow rate has the greatest effect on increasing the energy efficiency of the cycle, while increasing the burner temperature has the greatest effect on increasing the exergy efficiency of the cycle. Moreover, it is shown via multi-objective optimization of the proposed cycle that the exergy efficiency of the cycle increases by 31% and the cost of electricity generation decreases by 18% by applying optimized parameters.
Electropulsing-Induced α to β Phase Transformation of Ti–6Al–4V
Authors: Huang Jihui , Xu Zhutian , Deng Yujun , Peng Linfa
Published: September 2019

Electrically assisted forming (EAF) has been increasingly utilized as an effective auxiliary processing technology to improve the formability of hard-to-deform metals. Previous works have revealed that the phase transformation of titanium alloys subjected to electropulsing treatment (EPT) can occur at a lower temperature and in a remarkably shorter time compared with those subjected to the traditional heating treatment (THT). However, an in-depth experimental verification and further analysis is still missing so far. Therefore, to characterize the specific effects of EPT on α → β transformation process, both EPT and THT experiments were conducted on Ti–6Al–4V sheet specimens. After that, a calculation method based on the analysis of optical microscopic (OM) metallographs was developed to characterize the amount of phase transformation in EPT and THT. According to the results, it was found that the pulse current can significantly reduce the phase transus temperature and accelerate the transformation process in EPT compared with that in THT. Furthermore, the specific effects of EPT on transus temperature and phase transformation rate were investigated in detail. Based on that, the transformation kinetics of the electropulsing-induced α → β phase transformation was also analyzed using the Johnson–Mehl–Avrami model. It is revealed that the activation energies of both nucleation and growth of phase transformation are reduced by electric current. Hence, the phase transformation can start at a lower temperature and with a higher rate in EPT. The mechanism behind the effects was also discussed in detail in the present work.
Corrosion Characterization of Resistance Spot-Welded Aluminum and Steel Couple
Authors: Maddela Surender , Carlson Blair E.
Published: September 2019

The corrosion resistance of resistance spot-welded (RSW) Al–steel couples of varying combinations of 6016-T4 aluminum alloys and steel substrates, including with and without adhesive at the faying interface, has been successfully evaluated and compared with corresponding self-pierce riveted (SPR) couples. The corrosion resistance of resistance spot-welded Al–steel couples has performed well in cyclic corrosion testing (GMW 17026), and the results are comparable to or better than that of self-pierce riveted couples. SPR couples are more susceptible to galvanic corrosion than resistance spot-welded couples based upon experimentally measured electrochemical potentials from actual joints. The presence of adhesive acts significantly to reduce galvanic corrosion between aluminum alloy and stleel substrates, and moreover, tensile lap-shear strength significantly increased with structural adhesive for both RSW and SPR joining systems. However, despite the presence of adhesive, the lap-shear strength was reduced by more than 50% after cyclic corrosion testing to strength levels comparable to the lap-shear strength of couples having no adhesive and tested in ambient conditions.
Design for Crashworthiness of Categorical Multimaterial Structures Using Cluster Analysis and Bayesian Optimization
Authors: Liu Kai , Wu Tong , Detwiler Duane , Panchal Jitesh , Tovar Andres
Published: September 2019

This work introduces a cluster-based structural optimization (CBSO) method for the design of categorical multimaterial structures subjected to crushing, dynamic loading. The proposed method consists of three steps: conceptual design generation, design clustering, and Bayesian optimization. In the first step, a conceptual design is generated using the hybrid cellular automaton (HCA) algorithm. In the second step, threshold-based cluster analysis yields a lower-dimensional design. Here, a cluster validity index for structural optimization is introduced in order to qualitatively evaluate the clustered design. In the third step, the optimal design is obtained through Bayesian optimization, minimizing a constrained expected improvement function. This function allows to impose soft constraints by properly redefining the expected improvement based on the maximum constraint violation. The Bayesian optimization algorithm implemented in this work has the ability to search over (i) a real design space for sizing optimization, (ii) a categorical design space for material selection, or (iii) a mixed design space for concurrent sizing optimization and material selection. With the proposed method, materials are optimally selected based on multiple attributes and multiple objectives without the need for material ranking. The effectiveness of this approach is demonstrated with the design for crashworthiness of multimaterial plates and thin-walled structures.
Incorporating Field Effects Into Functional Product-System Architecting Methods
Authors: Otto Kevin , Hölttä-Otto Katja , Sanaei Roozbeh , Wood Kristin L.
Published: September 2019

System architecture and modularity decisions are inherent to preliminary concept design. Prior modularity research has considered minimizing interactions between modules and increasing the commonality among modular product variants. Effective approaches include function structure partitioning guidelines, affinity analysis, or matrix clustering algorithms. We consider here designs with field constraints, such as situations when elements cannot be placed in certain regions such as a high-temperature field, a high-pressure field, a high magnetic field, etc. which place constraints on modularity choices. Practical design guidelines are developed here for modularity considering field constraints. Two types of guidelines are proposed, field separation and concept generation. The field separation guidelines propose zonal boundaries within which system modules need be confined. The concept generation guidelines propose how to violate the field constraints through new concepts. Moving functionality from one side of a field boundary to the other is nontrivial and involves new concept generation for the modules to function at the higher or lower field values. The guidelines are defined and illustrated via multiple common examples as well as two extended case studies. We demonstrate the approach using field boundaries on an electric motor controller and on a medical contrast injector, and also use of fields to generated novel concepts. The guidelines support for modularity concept and embodiment decisions.
The Effects of the Connection Stiffness of Robotic Exoskeletons on the Gait Quality and Comfort
Authors: Shafiei Morteza , Behzadipour Saeed
Published: September 2019

An increase in the interaction forces/torques at the exoskeleton–human connections due to kinematic mismatches may consequently result in the user discomfort and/or lower performance of the exoskeleton. The stiffness of the exoskeleton–human connection elements plays a key role in this issue. The purpose of this study is to assess the effects of the exoskeleton–human connection stiffness on the user comfort and limb tracking error during normal gait. A biomechanical model of the leg was built and connected to a model of an exoskeleton by elastic connections whose stiffness tensors were identified experimentally for three participants. The effects of the connection stiffness on the gait performance were investigated using two indices: discomfort index (DI) and tracking error index (TEI), which is the difference between the human joint angle and that of the exoskeleton. DI was calculated based on the mechanical energy stored in the elastic connection elements. Although an increase of the stiffness magnitude in every direction results in DI growth, the torsional stiffness of the shank connection was found to be the most sensitive for DI. TEI, on the other hand, showed both increasing and decreasing trends with the stiffness increase in different directions. It was found that there are optimal values for some connection stiffness elements, especially shank connection, possibly due to intricacy of the knee joint, that would improve both DI and TEI. For instance, the decrease of the torsional and mediolateral shank connection stiffness improved DI and TEI by an average of about 50%.
Forward Acceleration of Kinematic Limbs for Redundant Serial–Parallel Manipulators
Authors: Lu Yi , Chang Zefeng , Ye Nijia
Published: September 2019

A forward acceleration of the kinematic limbs for the redundant serial–parallel manipulators is studied. The relationships between the input velocity/acceleration and the output general velocity/acceleration of the kinematic limbs are discovered. The forward kinematic Jacobian matrices and the forward kinematic Hessian matrices are derived. A unified forward acceleration of the kinematic limbs is established for solving the output general acceleration of the kinematic limbs by only giving the input general velocity/acceleration of every parallel manipulator. A novel 2(RPS + SPR + UPS + SPU) type serial–parallel manipulator is constructed, several formulas are derived for solving the full forward general acceleration of the kinematic limbs in the redundant serial–parallel manipulator based on the unified forward acceleration model. The theoretical solutions are proved to be correct by the simulation solution of the novel serial–parallel manipulator.
The Effect of Boron Nitride on Tribological Behavior of Mg Matrix Composite at Room and Elevated Temperatures
Authors: Aydin Fatih , Turan M. Emre
Published: September 2019

The goal of the study is to examine the dry sliding wear behavior of pure Mg and Mg/nano-boron nitride (BN) composite at elevated temperatures. The wear behavior of the samples was evaluated under loads of 5, 10, and 20 N, at sliding speed of 80, 130, and 180 mm s−1 and at temperatures of 25, 100, and 175 °C. The examination of worn surface, counterface, and wear debris was performed. The results showed that nano-BN particles lead to substantial enhancement of wear resistance for both room and elevated temperatures. Mg/0.25 BN has lower coefficient of friction values due to the presence of BN which act as solid lubricant. The wear mechanisms are thermal softening, melting, oxidation, abrasion, and delamination.
Boriding Temperature Effect on Micro-Abrasion Wear Resistance of Borided Tool Steel
Authors: Erdogan Azmi
Published: September 2019

Microstructure, hardness, and micro-abrasion behavior of borided H13 tool steel (borided at 1073, 1173, and 1273 K with nanoboron powder for 6 h) were studied. A single-phase boride layer was observed on the borided sample at 1073 K, while a double-phase boride layer was observed on the borided samples at high temperatures. FeB–Fe2B phases as well as CrB–MnB phases were determined in the XRD analysis of the samples. The hardness of the borided samples increased up to values above 2000 HV0.1. The thicker boride layer obtained due to the boriding process at high temperatures provided the retention of high hardness in the inner regions. The highest micro-abrasion resistance was obtained with the borided sample at 1273 K. Depending on the increasing load, volume losses increased on all samples under all conditions. Higher wear losses were determined in the tests performed with high-dimensional SiC. In the tests conducted with SiC F800, the dominant wear mechanism was micro-grooving wear mechanism, while in SiC F1200 tests the wear mechanism was micro-rolling and micro-scratching mechanisms. The abrasion resistance of the untreated sample was attributed to the abrasive particles sinking onto the surface.