bluuebunny/crossref_metadata_2025 huggingface dataset:
Global functions of O‐glycosylation: promises and challenges in O‐glycobiology
Authors: Wandall Hans H. , Nielsen Mathias A. I. , King‐Smith Sarah , de Haan Noortje , Bagdonaite Ieva
Published: August 2021

Mucin type O‐glycosylation is one of the most diverse types of glycosylation, playing essential roles in tissue development and homeostasis. In complex organisms, O‐GalNAc glycans comprise a substantial proportion of the glycocalyx, with defined functions in hemostatic, gastrointestinal, and respiratory systems. Furthermore, O‐GalNAc glycans are important players in host–microbe interactions, and changes in O‐glycan composition are associated with certain diseases and metabolic conditions, which in some instances can be used for diagnosis or therapeutic intervention. Breakthroughs in O‐glycobiology have gone hand in hand with the development of new technologies, such as advancements in mass spectrometry, as well as facilitation of genetic engineering in mammalian cell lines. High‐throughput O‐glycoproteomics have enabled us to draw a comprehensive map of O‐glycosylation, and mining this information has supported the definition and confirmation of functions related to site‐specific O‐glycans. This includes protection from proteolytic cleavage, as well as modulation of binding affinity or receptor function. Yet, there is still much to discover, and among the important next challenges will be to define the context‐dependent functions of O‐glycans in different stages of cellular differentiation, cellular metabolism, host–microbiome interactions, and in disease. In this review, we present the achievements and the promises in O‐GalNAc glycobiology driven by technological advances in analytical methods, genetic engineering, and systems biology.
Associations among elements in freshwater mussel shells (Unionidae) and their relation to morphology and life history
Authors: Hopper Garrett W. , Dickinson Gabriella K. , Atkinson Carla L.
Published: August 2021

Biogeochemical ecology of organisms typically focuses on C, N, and P despitec. 25 elements needed for organismal function. Embracing novel suites of elements in biomass is a first step in linking elements to organismal and ecological functions, improving our ability to predict how species interact with their environment. This research area has been fruitful for terrestrial plant ecologists, yet few studies have considered animal ecology within a framework encompassing elements beyond C, N, and P.

Freshwater mussels (Unionidae) are highly endangered filter‐feeding bivalves that can be important to ecosystem function. Interspecific trait variation influences soft tissue elemental composition that has been linked to ecosystem biogeochemical cycling using traditional C:N:P stoichiometric approaches. However, whether interspecific trait variation influences shell elemental composition is not well studied, especially for elements other than C, N, and P.

We quantified B, C, Ca, Cu, Fe, K, Mg, Mn, N, P, and Zn and constructed isometric log‐ratios (nutrient balances) for shells of seven species comprising diverse morphologies and two life history strategies to test whether shell elemental composition is influenced by these biological traits. Additionally, we evaluated whether the growth rate hypothesis applies to shell P concentration and elements associated with P in nutrient balances.

Bulk and trace elemental composition varied taxonomically and with biological traits. Nutrient balances for [C | P] and [C, Ca | P] were influenced by life history strategy. Shell P composition was negatively related to growth rates. Coincidentally, [C | P] and [C, Ca | P] were greater in the species with the highest growth rate (Lampsilis ornata), suggesting greater concentrations of C and Ca relative to P in shells of faster growing mussels. We hypothesise this observed pattern results from greater P allocation to soft tissue in fast growing mussels compared to slow growing mussels studied previously, but explicit tests of this hypothesis in a strict stoichiometric framework are needed.

Overall, we demonstrate how quantifying elements beyond C, N, and P, may be useful in uncovering elemental diversity associated with trade‐offs in elemental allocation among biological traits. Whether such elemental diversity correlates to evolutionary history or contributes to the biogeochemical template of freshwater habitats remains to be seen but should be explored.
Windthrows promote higher diversity of saproxylic beetles (Coleoptera: Passalidae) in a Central Amazon forest
Authors: Alencar Janderson Batista Rodrigues , da Fonseca Claudio Ruy Vasconcelos , Marra Daniel Magnabosco , Baccaro Fabrício Beggiato
Published: August 2021

Natural disturbances change environmental conditions that play an important role in controlling biodiversity. Large‐scale windthrows (i.e. snapped and uprooted trees) promoted by convective systems cause severe tree mortality and can alter the dynamics of several insect taxons in forests.

We assessed the effect of large‐scale windthrows resulting from a squall line event in January 2005 on strictly saproxylic beetle assemblages in Central Amazonia. Using a paired sampling design comparing windthrown and old‐growth forest, we investigated the responses of different metrics of Passalidae diversity (richness, abundance and composition).

We found a higher richness and abundance of species in windthrown areas compared with old‐growth forest, and a correlation between species composition and the tree mortality gradient.

Differences in the richness and composition of the Passalidae assemblage between disturbed and old‐growth forest suggest that the tree mortality gradient created by windthrows promotes the diversity of saproxylic beetles in Central Amazonia.
Concerns and psychological well‐being of healthcare workers during theCOVID‐19 pandemic in a tertiary care hospital in New South Wales
Authors: Naqvi Syeda Shaher Bano , Davis Joshua , Pickles Robert W. , Loewenthal Mark R.
Published: August 2021

Background

In early 2020, the impending COVID‐19 pandemic placed a once‐in‐a‐generation professional and personal challenge on healthcare workers. Publications on direct physical disease abound. The authors wanted to focus on doctors' psychological well‐being.

Aims

To assess the impact of the COVID‐19 pandemic on doctors' well‐being and evaluate their concerns as the pandemic progressed.

Methods

A mixed‐methods, hospital‐based survey was sent to doctors at the 650‐bed tertiary referral hospital in NSW at two different periods (late‐March and early May 2020). A validated mental well‐being tool (Short Warwick Edinburgh Mental Well‐being Scale (SWEMWBS)) was combined with COVID‐19‐specific questions.

Results

Two hundred and thirty‐five responses were obtained from 450 doctors, with a response rate of 32% in the first survey and 20% in the second. The majority (35%) of respondents were doctors‐in‐training, followed by staff‐specialists (23%). The highest response was from frontline workers in both surveys, including the intensive care unit (27%), anaesthesia (21%) and emergency department (13%). ‘Extreme concern’ regarding personal protective equipment (PPE) shortage dropped from 22.6% to 2.2% and ‘extreme concern’ of contracting COVID‐19 fell from 22.6% to 3.4% in the second survey. The proportion of respondents with a ‘low’ psychological well‐being score improved from 38% to 27% between the two surveys. The resulting mean improvement in the SWEMWBS was 3.49 (95% confidence interval = 3.06–3.91,P < 0.001).

Conclusion

Both COVID‐19 specific concerns and psychological well‐being improved greatly in the second survey. Possible explanations are the fall in COVID‐19 cases in the district, improvements in PPE supply and supportive measures communicated to doctors during this period.
Exploration of the views and experiences of research healthcare professionals during their redeployment to clinical roles during the COVID‐19 pandemic
Authors: Veerapen Jessry D. , McKeown Eamonn
Published: August 2021

Aim

This study aimed to explore the views and experiences of research healthcare professionals towards their redeployment to frontline clinical roles during the COVID‐19 pandemic.

Background

Healthcare professionals working in research were redeployed during the COVID‐19 pandemic to support the delivery of clinical services across the National Health Service. They are experienced clinicians with research knowledge and skills, and specific working patterns. It is important to understand how these professionals were used and supported during their transition to clinical roles during the pandemic.

Method

Between July and September 2020, 15 research healthcare professionals were recruited into this qualitative study. Each participant completed a single semi‐structured interview lasting approximately 30–60 min, conducted remotely using a teleconferencing platform. Interviews were transcribed verbatim, and data analysed by the process of inductive thematic analysis with the assistance of NVivo 12.06 (Nov, 2019).

Findings

Four main themes were identified from analysis of the transcripts: (a) initial personal response to the pandemic (subthemes: of anxieties due to unknown disease impact and concern for others); (b) mobilization for clinical redeployment (subthemes: motivations for voluntary redeployment, the professional challenges, personal fears and the organization and preparedness for redeployment); (c) adaptive deployment to clinical roles (subthemes: adapting to new roles and responsibilities, challenges faced and coping mechanisms), (d) reflections and learnings (subthemes: reintegration to original roles and sense of achievement).

Conclusion

Research healthcare professionals are highly adaptable professionals equipped with core transferable skills. With the appropriate support, re‐familiarization and induction they are a valuable resource during the pandemic response.

Implications to practice

Research healthcare professionals are experienced practitioners with transferrable skills and strong sense of duty and resilience.

Induction programmes to promote recalibration to clinical settings would improve their adaptability, foster confidence and emotional well‐being.

Careful consideration is required prior to mass redeployment to ensure research continuity in both COVID‐19 and other health conditions.
Can video games change attitudes towards history? Results from a laboratory experiment measuring short‐ and long‐term effects
Authors: Kolek Lukáš , Šisler Vít , Martinková Patrícia , Brom Cyril
Published: August 2021

This study investigates a video game's effects on implicit and explicit attitudes towards depicted historical events in the short‐ and long‐term on a sample of 148 young adults. We used, as an intervention tool, a serious game Czechoslovakia 38–89: Borderlands that deals with the expulsion of the Sudeten Germans from the former Czechoslovakia after the WWII. Results showed more negative pretest‐posttest explicit attitude changes towards the expulsion on a general level (d = −0.34) and a specific level (d = −0.53) compared to the control group. Over the long‐term, group differences in attitude change remained significant for the specific level (d = −0.44), but not for general one (d = −0.16). Exploratory analysis on the item level indicated that especially attitudes towards the expulsion's (un)fairness were affected by the game. However, no significant changes were found in implicit attitudes in the experimental group. This study is the first of such scale to empirically investigate video games' effects on a society's historical awareness.
MRTF‐A regulates myoblast commitment to differentiation by targeting PAX7 during muscle regeneration
Authors: Song Ruhui , Zhao Shengnan , Xu Yue , Hu Jian , Ke Shuangao , Li Fan , Tian Gaohui , Zheng Xiao , Li Jiajun , Gu Lixing , Xu Yao
Published: August 2021

Myocardin‐related transcription factor‐A/serum response factor (MRTF‐A/SRF), a well‐known transcriptional programme, has been proposed to play crucial roles in skeletal muscle development and function. However, whether MRTF‐A participates in muscle regeneration and the molecular mechanisms are not completely understood. Here, we show that MRTF‐A levels are highly correlated with myogenic genes using a RNA‐seq assay, which reveal that MRTF‐A knockdown in C2C12 cells significantly reduces PAX7 expression. Subsequent in vitro and in vivo data show that MRTF‐A and PAX7 present identical expression patterns during myoblast differentiation and CTX‐induced muscle injury and repair. Remarkably, MRTF‐A overexpression promotes myoblast proliferation, while inhibiting cell differentiation and the expression of MyoD and MyoG. MRTF‐A loss of function produces the opposite effect. Moreover, mice with lentivirus (MRTF‐A) injection possesses more PAX7+ satellite cells, but less differentiating MyoD+ and MyoG+ cells, leading subsequently to diminished muscle regeneration. Our mechanistic results reveal that MRTF‐A contributes to PAX7‐mediated myoblast self‐renewal, proliferation, and differentiation by binding to its distal CArG box. Overall, we propose that MRTF‐A functions as a novel PAX7 regulator upon myoblast commitment to differentiation, which could provide pathways for dictating muscle stem cell fate and open new avenues to explore stem cell‐based therapy for muscle degenerative diseases.
Visual essentialism & social kinds
Authors: Tullmann Katie
Published: August 2021

Scholars increasingly deny that they are strictly biological. Instead, these scholars argue that they are socially constructed. One challenge is to square the notion of social kinds with the apparent perception of those categories. I argue that we do not perceive social categories such as race. Instead, racial categories are visually encoded based on visible markers that are proxies for social kinds. Thus, I argue that the assumption of seeing social categories commits us to a flawed theory of visual essentialism: the idea that some social kinds are visible properties that are biologically determined.
Electrical impedance tomography to measure lung ventilation distribution in healthy horses and horses with left‐sided cardiac volume overload
Authors: Sacks Muriel , Byrne David P. , Herteman Nicolas , Secombe Cristy , Adler Andy , Hosgood Giselle , Raisis Anthea L. , Mosing Martina
Published: August 2021

Background

Left‐sided cardiac volume overload (LCVO) can cause fluid accumulation in lung tissue changing the distribution of ventilation, which can be evaluated by electrical impedance tomography (EIT).

Objectives

To describe and compare EIT variables in horses with naturally occurring compensated and decompensated LCVO and compare them to a healthy cohort.

Animals

Fourteen adult horses, including university teaching horses and clinical cases (healthy: 8; LCVO: 4 compensated, 2 decompensated).

Methods

In this prospective cohort study, EIT was used in standing, unsedated horses and analyzed for conventional variables, ventilated right (VAR) and left (VAL) lung area, linear‐plane distribution variables (avg‐max VΔZLine, VΔZLine), global peak flows, inhomogeneity factor, and estimated tidal volume. Horses with decompensated LCVO were assessed before and after administration of furosemide. Variables for healthy and LCVO‐affected horses were compared using a Mann‐Whitney test or unpairedt‐test and observations from compensated and decompensated horses are reported.

Results

Compared to the healthy horses, the LCVO cohort had significantly less VAL(mean difference 3.02; 95% confidence interval .77‐5.2;P = .02), more VAR(−1.13; −2.18 to −.08;P = .04), smaller avg‐max VΔZLLine(2.54; 1.07‐4.00;P = .003) and VΔZLLine(median difference 5.40; 1.71‐9.09;P = .01). Observation of EIT alterations were reflected by clinical signs in horses with decompensated LCVO and after administration of furosemide.

Conclusions and Clinical Importance

EIT measurements of ventilation distribution showed less ventilation in the left lung of horses with LCVO and might be useful as an objective assessment of the ventilation effects of cardiogenic pulmonary disease in horses.
No fact of the matter
Authors: Baumann Marius
Published: August 2021

Theodore Sider has argued that while there are some philosophical debates about which there is no fact of the matter, debates in normative ethics are likely not among them. This essay investigates a possible counterexample: the debate about so‐called dirty hands. The essay first surveys several cases where No‐Fact‐of‐the‐Matter (NFM) claims have been made. Taking its cue from these cases, it then outlines two strategies that factualists about some domain can take, as well as two non‐factualist counter strategies. Next, it shows how an NFM claim can be defended for the debate about dirty hands. Finally, it argues that this NFM claim is at least as, if not more, plausible for normative ethics as it is for the other instances where NFM claims have been made.
Humpback whale abundance in Hawai‘i: Temporal trends and response to climatic drivers
Authors: Frankel Adam S. , Gabriele Christine M. , Yin Suzanne , Rickards Susan H.
Published: August 2021

In 2001, we began long‐term monitoring using scan sampling methodology to study the relative abundance and distribution of humpback whales (Megaptera novaeangliae) on their Hawaiian breeding grounds. Samples were collected annually (2001–2019) from a shore site overlooking Kawaihae Bay, Hawaiʻi Island. Each sample included the number of whales, pod composition, and position. Whale numbers increased from 2001 to 2015, with increasing variability after 2010. Numbers then declined, including a precipitous 60% drop between 2015 and 2016. Crude birth rate fell from 6.5% in 2015 to 1.1% in 2016. We used generalized additive models, including predictor variables of year, date, observational conditions, and observer, to establish a base model. Climatic indices were individually added to base models, and their contributions were evaluated using Akaike information criteria. Models indicated that whale numbers and crude birth rate fell when climate indices reflected warmer water on high latitude feeding grounds in the North Pacific. Our results show that oceanographic conditions during prior feeding seasons correspond with the reproductive rate and the number of whales in Hawaiʻi. Continued long‐term monitoring of whale populations is essential to documenting and understanding marine ecosystem responses to global climate change.
Efficacy of antitachycardia pacing alert by remote monitoring of implantable cardioverter‐defibrillators for out‐of‐hospital electrical storm
Authors: Otsuki Sou , Izumi Daisuke , Sakaguchi Yuta , Suzuki Naomasa , Hakamata Takahiro , Ikami Yasuhiro , Hasegawa Yuki , Yagihara Nobue , Iijima Kenichi , Chinushi Masaomi , Minamino Tohru , Takayuki Inomata
Published: August 2021

Background

Remote monitoring (RM) has been shown to reduce all‐cause mortality in patients with implantable cardioverter‐defibrillators or cardiac resynchronization therapy defibrillators (ICD/CRT‐D). Not all devices transmit an alert for antitachycardia pacing (ATP) therapy, and it is unknown whether differences of RM alert affect the outcomes of electrical storm (ES).

Methods

We enrolled 42 patients with ICD/CRT‐D whose out‐of‐hospital ES were detected by RM between 2013 and 2020. We divided their 54 episodes into two groups (ATP‐alert‐on; 22, ATP‐alert‐off; 32), and clinical outcomes were compared between the two groups.

Results

In 35 of 54 episodes of ES, ventricular tachycardia (VT) could be terminated within 24 h of ES onset just by ATP (ATP‐alert‐on: 14, ATP‐alert‐off: 21); however, many patients subsequently received shock delivery for VT. Among the 35 episodes, only in ATP‐alert‐on group, seven patients were prompted to visit our hospital without ICD shock through confirmation of ES by ATP‐alert. Episodes that led to shock delivery 24 h or longer after the ES onset were significantly less common in the ATP‐alert‐on group (ATP‐alert‐on: 1/14, ATP‐alert‐off: 9/21, p = .03). Although there were no significant differences in the number of shock deliveries between episodes in the two groups, the number of ATP deliveries were significantly fewer in the ATP‐alert‐on group (12[7‐26] vs. 29[16‐53] in ATP‐alert‐off group, p = .03). Multivariate logistic regression analyses showed that the only ATP‐alert significantly reduced ATP deliveries (HR = 0.14, 95%CI = 0.04‐0.57, p = .003).

Conclusion

Remote monitoring with an ATP‐alert function during electrical storm may reduce appropriate ICD therapy through prompting early review.
The AMP‐dependent kinase pathway is upregulated in BAP1 mutant uveal melanoma
Authors: Chua Vivian , Han Anna , Bechtel Nelisa , Purwin Timothy J. , Hunter Emily , Liao Connie , Harbour J. William , Aplin Andrew E.
Published: August 2021

Metastatic uveal melanoma (UM) responds poorly to targeted therapies and immune checkpoint inhibitors. Loss of BRCA1‐associated protein 1 (BAP1) via inactivating mutations in the BAP1 gene is associated with UM progression. Thus, molecular alterations caused by BAP1 dysfunction may be novel therapeutic targets for metastatic UM. Here, we found that phosphorylation of AMP‐dependent kinase (AMPK) was elevated in BAP1‐altered (or mutant) compared to BAP1‐unaltered (or wild‐type [WT]) UM tumors. As a readout of AMPK pathway activation, phosphorylation of an AMPK downstream effector, acetyl‐CoA‐carboxylase (ACC), was also elevated. BAP1 re‐expression in BAP1‐null UM cell lines decreased phospho‐AMPK (pAMPK) and phospho‐ACC (pACC) levels. AMPK phosphorylation is mediated by calcium/calmodulin dependent protein kinase kinase 2 (CaMKK2) and potentially liver kinase B1 (LKB1) in BAP1 mutant UM cells. Knockdown of AMPKα1/2 reduced the viability of BAP1 mutant UM cells, indicating a survival function of AMPK in BAP1 mutant UM. Our data suggest that the AMPK pathway is an important mechanism mediating the survival of BAP1 mutant UM. Targeting the AMPK pathway may be a novel therapeutic strategy for metastatic UM.
A novel HLA‐C*15 allele, HLA‐C*15:192, identified by next generation sequencing in a Chinese individual
Authors: Quan Zhan‐Rou , Li Zhen , Zou Hong‐Yan
Published: August 2021

Identification of the novel HLA‐C*15:192 allele that differs from HLA‐C*15:02:01:01 at one position in exon 2.
Intermedia Agenda Setting and Grassroots Collectives: Assessing Global Media’s Influence on Greek News Outlets
Authors: Papadopoulou Lambrini , Kavoulakos Karolos , Avramidis Christos
Published: August 2021

This study focuses on a variety of grassroots collectives that emerged during the Greek economic crisis and aims to record activists’ own perceptions regarding the way that domestic media reacted after these collectives featured on the front pages of global news outlets. Drawing on 10 in depth interviews with activists participating in five grassroots collectives, this study brings together social movement and communications theoretical frameworks. Interviewees were asked about their perceptions regarding the role that global elite media coverage may have played in the salience of their endeavors in domestic media. Subsequently, we tested their personal testimonies by implementing a time series analysis on three Greek newspapers for a period of seven days before and after a front page publication in global elite media. Findings suggest that there is a big discrepancy between the perceived and the actual impact of global elite media on the agenda of domestic newspapers. To this end, further research should be undertaken to specify the exact characteristics that influence which grassroots collective will gain prominence in the public realm.
Prevalence of COVID-19 genomic variation in Africa: a living systematic review protocol
Authors: Adjei George , Enuameh Yeetey A. , Thomford Nicholas E.
Published: August 2021

Objective:

The objective of this living systematic review is to synthesize the available evidence on the prevalence of types of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomic variations in Africa.

Introduction:

The burden of the coronavirus disease 2019 (COVID-19) pandemic on the health, well-being, and global economy (especially the fragile economies of African countries) is significant. Profiling the genomic and geographical variations of SARS-CoV-2, a causative agent of COVID-19, may be important for future decision-making, policy guidelines, and development of drugs and vaccines. However, little is known about the up-to-date prevalence of genomic and geographical variations of SARS-CoV-2 virus on the African continent.

Inclusion criteria:

This living systematic review will include studies on the prevalence of SARS-CoV-2 genetic strains and mutations obtained from sequencing data of samples from individuals of all ages and sexes using the next generation sequencing approaches in studies conducted in Africa.

Methods:

The search strategy will be developed to retrieve both published and unpublished data. Published data will be obtained from electronic databases. Unpublished data will be obtained from conference proceedings, preprints, theses/dissertations, electronic search engines, and COVID-19–dedicated websites. Relevant published or unpublished data in the English language from January 2020 will be considered. Studies will be selected based on the inclusion criteria of the review. The selected studies will be critically appraised for methodological quality by two independent reviewers and data extracted from eligible studies. Finally, meta-analysis will be done, if feasible, to pool prevalence estimates after heterogeneity of the data has been analyzed.

Systematic review registration number:

PROSPERO CRD42020211451
Effect of different levels of stroke volume variation on the endothelial glycocalyx of patients undergoing colorectal surgery: A randomized clinical trial
Authors: Liu Yi , Chen Gang , Gao Jie , Chi Menglin , Mao Mengmeng , Shi Yizheng , Ji Zexuan , Fu Qiang , Zhang Hong , Xu Zhipeng
Published: August 2021

New Findings

What is the central question of this study?

Massive infusion can destroy the endothelial glycocalyx. We compared the serum concentrations of endothelial glycocalyx components and atrial natriuretic peptide and the outcomes of patients with different levels of stroke volume variation (SVV).

What is the main finding and its importance?

With a decrease in SVV, the serum concentrations of endothelial glycocalyx components and atrial natriuretic peptide increased, whereas the oxygenation index decreased. When the intraoperative SVV was maintained at 7−10%, the patients had better postoperative recovery and shorter postoperative hospital stays. Therefore, it is advisable to maintain the SVV between 7 and 10%.

Dynamic haemodynamic parameters, such as stroke volume variation (SVV), can be used for blood volume monitoring. However, studies have determined the SVV threshold but not the optimal level. The endothelial glycocalyx (EG) plays an important role in maintaining vascular permeability. Moreover, rapid and massive infusion can lead to the degradation, shedding and destruction of the EG. We aimed to explore the effects of different SVV values (11–14, 7–10 or 3–6%) on the EG in 54 patients who were scheduled for elective colorectal tumour surgery and to identify the optimal peri‐operative fluid therapy strategy. The concentrations of EG degradation products (heparin sulphate, hyaluronic acid and syndecan‐1) and atrial natriuretic peptide were higher when the SVV was maintained between 3 and 6% after fluid therapy compared with pre‐infusion (P < 0.05). Comparison of postoperative complications and hospitalization time among the three SVV levels was not statistically significant (P > 0.05). The postoperative hospitalization time in patients with SVV of 7–10% was shorter than that in patients with SVV of 3–6%. Infusion of a large volume of fluid, with increasing EG degeneration and atrial natriuretic peptide concentrations, might be related to postoperative outcomes.
Ocorrência de Rocha Alcalina no Município de Piraí, RJ, e sua Relação com o Lineamento de Além Paraíba (Nota Preliminar)
Authors: Ferrari André Luiz , Dupuy Ivan Sérgio Siqueira , Brenner Thomas Lafayette
Published: August 2021

The Serra dos Tomazes, located in the Pirai District, RJ, consists of an intrusive alkaline body, composed mainly of micronepheline-syenites. This alkaline body intrudes metatexites of the "Paraiba do Sul" folded belt. Mylonitic Zones we re recognized south of the intrusive alkaline body, and they may be associated with the Alem Paraiba Lineament. This lineament corresponds to an ENE striking transcurrent fault. This fault belongs to a system of transcurrent faults that is called the "São Paulo Transcurrence Zone". The strike-slip faults that form the bulk of the "Sao Paulo Transcurrence Zone" are generally right-lateral. The Serra dos Tomazes alkaline body is probably associeted, in time and in origin, with other alkaline intrusions in the State of Rio de Janeiro. This alkaline magmatism seems to be associated, at least geographically, with the "Sao Paulo Transcurrence Zone".
Contribuição ao Estudo da Localização Industrial: O Caso de Niterói
Authors: Teixeira Marlene P. V.
Published: August 2021

All problems related to urban land use are of great interest not only to geographers but to all those scholars who are interested in studying the spatial organization of economic activities within the city. The study of industrial location, however, has been traditionally awarded a low priority in spatial research, which has tended to emphasize the locational characteristics of other economic activities which take place in the city. Based on a brief review of the literature on industrial location, the present study tries to identify some general principles which govern the location of secondary sector activities in the city through time. These principles are then tested for their relevancy in the context of downtown Niterói, the second most important município of the Rio de Janeiro Metropolitan Region.
Estudo Quantitativo de Ambiente: O Oeste do Estado do Rio de Janeiro
Authors: Coelho Maria Célia Nunes
Published: August 2021

This paper is an environmental quantitative study: The Western portion of the State of Rio de Janeiro, based on multiple features. The objective was to give basic information to the environment management of the area. In this study, considering regional differenciations, the experimental units (grid squares of 4 kmÂ²) were grouped into units based on topography. Environmental analyses (caracterizations and investigations of the correlation structures) of each topographical unit as well as the comparison among them were made feasible through statistical techniquesenumerations of descriptive statistics, correlation, factor and cluster analyses - which numerically confirmed the consistency of the units of relief previously defined.
Estudo dos Sedimentos de Fundo do Alto Rio Grande: Município de Nova Friburgo
Authors: Cunha Sandra Baptista da
Published: August 2021

The present paper is a contribution to the study of the Upper Grande River, Nova Friburgo. It is a preliminary study of the relationship between the river-bed sediments and the declivity of the river profile. Granulometric analysis were performed on channel sediments in attempt to find a sedimentological caracterization of the river. The following parameters were computed: central tendency (median grain size (Md;) and mean grain size (M Z) , dispersion (ÏƒI) , assimetry (SK I) and curtosis (K G).The data analysed shows two distinct environments: that of the headwaters and that of the base level. Both environments are composed of poorly selected sediments.
A Periferização da População de Baixa Renda em Relação ao Mercado de Trabalho: O Caso do Conjunto Habitacional de Cidade Alta
Authors: Sant'Anna Marina
Published: August 2021

This paper presents the results of a study of a low-income housing project, i.e. the Conjunto Habitacional de Cidade Alta - Cordovil. The objective of this study was firstly to de monstrate that the resettlement proceeding used in this housing project has ended in a peripherization process, consiãe ring the localization of the low-income families labor market, and secondly to explain how this peripherization process is a consequence of the capitalist system mechanics. The data over which this study was developed was obtained through the employment of an enquiry with the Conjunto's residents.
Saturn Satellites and Minor Planets Positions in February 1933 at Esq, La Silla
Authors: Debehogne H. , Mourão R. R. De Freitas , Machado L. E. Da Silva
Published: August 2021

In february 1983. we have observed the Satellites of Saturn and Minor Planets at the ESO, La Silla, Chile. The instrument GRO (D=40cm; f=4m) was used. Having clear skies, magnitude 18 could be attained. Measures and reductions were performed at the Observatoire royal de Belgique with the Ascorecord measuring machine (0,1Âµ) and by means of five reference stars on the UNIVAC computer of the Royal Institute of Meteorology (SAO Star Catalogue, Least Squaras and Dependences Methods).
Grandes Projetos, Tecnologia e Questão Ambiental: Carajás e Energia Nuclear
Authors: Coelho Maria Célia Nunes , Cota Raymundo Garcia
Published: August 2021

The desire of growth aiming at international economic integration and the need of adjustment to energy crisis as well as world economic difficulties have constituted a stimulus to investments in big projects such as Nuclear Energy Project and that of Carajás. In addition to an expanding of foreign debt so preventing souvereign national development, the installation of big projects represents a threat to large sectors of the population and space, through exploitation of resources. Considering the lack of previous studies of environmental impacts plus scientific knowledge to back such projects, this work purports to (1) briefly expose Carajás and Nuclear programs; (2) raise conceptual issues as well as possible consequences for the country. Main points will be summarised and certain criteria for a technological eva luation will be examined.
Time Domain Study on the Construction Mechanism of Milling Stability Lobe Diagrams With Multiple Modes
Authors: Li Weitao , Wang Liping , Yu Guang
Published: August 2021

The stability lobe diagram (SLD) is an important expression way of milling stability prediction result. The SLD obtained by only selecting the most flexible mode fails to predict the chatter if the milling process is dominated by multiple modes. To reveal the relationship between the SLD with multiple modes and the SLDs corresponding to each single mode, this paper studies the construction mechanism of the SLD with multiple modes by using the time domain method. First, the milling dynamic model of the tool with multiple modes is established. Then, the numerical method based on the Newton-Cotes rules is used to solve the milling dynamic model with multiple modes whose solution is in the form of the SLD. It shows that the SLD with multiple modes can be approximated by using the lowest envelope of the SLDs corresponding to each single mode. Finally, two study cases are adopted to verify the construction mechanism of the SLD with multiple modes. To verify the correctness of the SLD with multiple modes, a series of milling tests are carried out. The experimental results agree with the simulation results, which means the proposed time domain method can reveal the construction mechanism of the SLD with multiple modes.
The FDTD Analysis of Near-Field Response for Microgroove Structure With Standing Wave Illumination for the Realization of Coherent Structured Illumination Microscopy
Authors: Guan Yizhao , Kume Hiromasa , Kadoya Shotaro , Michihata Masaki , Takahashi Satoru
Published: August 2021

Microstructures are widely used in the manufacture of functional surfaces. An optical-based super-resolution, non-invasive method is preferred for the inspection of surfaces with massive microstructures. The Structured Illumination Microscopy (SIM) uses standing-wave illumination to reach optical super-resolution. Recently, coherent SIM is being studied. It can obtain not only the super-resolved intensity distribution but also the phase and amplitude distribution of the sample surface beyond the diffraction limit. By analysis of the phase-depth dependency, the depth measurement for microgroove structures with coherent SIM is expected. FDTD analysis is applied for observing the near-field response of microgroove under the standing-wave illumination. The near-field phase shows depth dependency in this analysis. Moreover, the effects from microgroove width, the incident angle, and the relative position between the standing-wave peak and center of the microgroove are investigated. It is found the near-field phase change can measure depth until 200 nm (aspect ratio 1) with an error of up to 20.4 nm in the case that the microgroove width is smaller than half of the wavelength.
Numerical Study on Tip Shape of Near-Field Optical Fiber Probe for Detecting Electric Field Intensity of Whispering Gallery Mode Resonance
Authors: Liu Yushen , Kadoya Shotaro , Michihata Masaki , Takahashi Satoru
Published: August 2021

For the measurement of micron-sized components, there are many methods widely used, such as by using CMM, and the size of the probe sphere of CMM is essential for measuring. In order to accurately measure the size of the probe sphere, a method by using Whispering Gallery Mode (WGM) resonance has been proposed. To measure the diameter of the microsphere with this method, the resonance wavelength and the angular mode number of WGM need to be known. The resonance wavelength can be measured by a wavelength meter and the angular mode number can be obtained by using the near-field optical fiber probe to measure the electric field intensity distribution on the surface of the microsphere. The detecting sensitivity of probe on electric field intensity is quite important for angular mode number measuring, which is deeply related to the accuracy of microsphere diameter measurement. In the process of electric field intensity detecting, the sensitivity of the probe can be affected by its shape. Therefore, the effect of probe tip shape on measurement was studied to optimize it. In this study, the effect of probe tip diameter, angle and shape on the measuring of electric field intensity on microsphere surface was investigated.
Effect of Heat Treatment on Microstructures and Mechanical Properties of SS316L by Micro Selective Laser Melting
Authors: Fu Jin , Qu Shuo , Ding Junhao , Song Xu , Fu Mingwang
Published: August 2021

Recently, micro selective laser melting (μSLM) system equipped with finer laser beam has been developed to improve additive manufacturing resolution. The microstructures and properties of μSLM produced metals and alloys could be different from those by conventional-size SLM, which warrants further investigation. Moreover, the widely used material, SS316L stainless steel, demonstrates unique cellular structures and excellent combination of strength and ductility after SLM. How the microstructures evolve after heat treatment and affect the mechanical properties remain to be clarified for μSLMed SS316L. In this study, the effect of heat treatment on the microstructures and mechanical properties of μSLMed SS316L was studied. Two heat treatment methods, namely HT650°C-2h and HT950°C-2h, were employed. It is found that the heat treatment has no effect on phase formation, and a preferred grain growth orientation with (110) plane along building direction and a single austenite phase was detected in all samples. Cellular structures were observed in as-printed samples and found to grow up a little bit after HT650°C-2h, but disappear after HT950°C-2h. Besides, more carbides are detected after HT650°C-2h, while they are partially dissolved after HT950°C-2h. For mechanical properties, the as-printed sample shows the best combination of strength and ductility, thanks to the strengthening effects from cellular structures and dislocations. The inferior mechanical properties after heat treatment is attributed to reduction of dislocations and disappearance of cellular structures. In addition, the presence of carbides can significantly reduce the ductility.
Towards a Digital Depot to Support Sustainable Manufacturing During Crisis Response
Authors: Diaz-Elsayed Nancy , Morris K. C. , Schoop Julius
Published: August 2021

The COVID-19 pandemic has imposed new challenges to maintaining sustainability in our manufacturing operations. With such high variability in demand for urgently needed products (e.g., personal protective equipment, testing technologies) and shifts in the needed capabilities of already complex production systems, sustainability challenges concerning waste management, life cycle impact characterization, and production operations have come to light. An extensive amount of data can be extracted from manufacturing systems, but it is not yet being used to improve the performance of production systems and maintain sustainability strategies during times of distress. This article proposes the concept of a Digital Depot. Being virtual in nature, the depot can contain plans and data for many different types of crises and contain a wider array of products than would be available in a physical, national stockpile. The information could be made available on demand to a national base of manufacturers to help them swiftly pivot to the production of critically needed goods while building on their existing manufacturing capabilities. The contents of the Digital Depot would be applicable to several stages pertinent to manufacturing operations including product definition, production planning information, asset and factory-level data, as well as data concerning the supply chain, distribution, and end-of-life stages. Future work is recommended in the development of templates for robust and secure data sharing, as well as multi-disciplinary identification of businesses cases for data-driven collaborative and sustainable manufacturing practices enabled by the Digital Depot.
Anisotropic Material Behaviors of 3D Printed Carbon-Fiber Polymer Composites With Open-Source Printers
Authors: Garcia Jordan , Harper Robert , Lu Y. Charles
Published: August 2021

Composite products are often created using traditional manufacturing methods such as compression or injection molding. Recently, additive manufacturing (3D printing) techniques have been used for fabricating composites. 3D printing is the process of producing three-dimensional parts through the successive combination of various layers of material. This layering effect in combination with exposure to ambient (or reduced) temperature and pressure cause the finished products to have inconsistent microstructures. The inconsistent microstructures along with the oriented reinforcing fibers create anisotropic parts with difficulty to predict mechanical properties. In this paper, the mechanical properties of fiber reinforced polymer composites produced by additive manufacturing technique (3D printing) and by traditional manufacturing technique (compression molding) were investigated. Three open-source 3D printers, i.e. FlashForge Dreamer, Tevo Tornado, and Prusa i3 Mk3, were used to fabricate bending samples from carbon-fiber reinforced ABS (acrylonitrile butadiene styrene). Results showed that there exist significant discrepancies and anisotropies in mechanical properties of 3D printed composites. First, the properties vary greatly among parts made from different printers. Secondly, the mechanical responses of 3D printed parts strongly depend upon the orientations of the filaments. Parts with the infill oriented along the length of the specimens showed the most favorable mechanical responses such as Young’s modulus, maximum strength, and toughness. Thirdly, all 3D printed parts exhibit inferior properties to those made by conventional manufacturing. Finally, theoretical modeling has been attempted to predict the mechanical responses of 3D printed products and can potentially be used to “design” the 3D printing processes to achieve the optimal performance.
Modeling and Experimental Validation of Droplet Generation in Electrohydrodynamic Inkjet Printing for Prediction of Printing Quality
Authors: Jiang Liangkui , Premaratne Pavithra , Huang Yanhua , Zhang Zhan , Qin Hantang
Published: August 2021

Electrohydrodynamic (EHD) Inkjet printing is one type of micro/nano scale additive manufacturing technique. The droplet generation mechanism plays an important role in electrohydrodynamic (EHD) inkjet printing due to its significant effects on process control, printing quality, and printing performance. The large variation of printing system design used in EHD printing and the limited process optimization techniques resulted in a complex experimental procedure to determine a working condition, and it takes a long time to finish such experiments. It is also challenging to understand the droplet generation mechanism’s fluid dynamics under a multiphysical field in EHD printing. The development of computational fluid dynamics (CFD) and the recent advancements in high performance computing can be utilized to alleviate the aforementioned challenges. In this study, a numerical simulation model was developed to model the droplet generation mechanism in EHD printing based on Taylor-Melchar leaky-dielectric model. This model successfully simulated a single printing cycle, including Taylor cone formation, cone-jet generation, jet break, and jet retraction. A further simulation study demonstrated accurate predictions of the droplet volume and the jetting diameter under different working conditions (e.g., voltages and duty ratio of pulsed AC voltage). Experiments validated the simulation model and its prediction results. Such advancement in modeling can be used to optimize the printing process as well as guide the quick selection of printing conditions given a new ink.
Prediction of Cutting Force in Bone Cutting Using Finite Element Analysis
Authors: Prasannavenkadesan Varatharajan , Pandithevan Ponnusamy
Published: August 2021

In orthopedic surgery, bone cutting is an indispensable procedure followed by the surgeons to treat the fractured and fragmented bones. Because of the unsuitable parameter values used in the cutting processes, micro crack, fragmentation, and thermal osteonecrosis of bone are observed. Therefore, prediction of suitable cutting force is essential to subtract the bone without any adverse effect. In this study, the Cowper-Symonds model for bovine bone was developed for the first time. Then the developed model was coupled with the finite element analysis to predict the cutting force. To determine the model constants, tensile tests with different strain rates (10−5/s, 10−4/s, 10−3/s, and 1/s) were conducted on the cortical bone specimens. The developed material model was implemented in the bone cutting simulation and validated with the experiments.