bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural O-Glycoform Heterogeneity of the SARS-CoV-2 Spike Protein Receptor-Binding Domain Revealed by Native Top-Down Mass Spectrometry
Authors: Roberts David S. , Mann Morgan W. , Melby Jake A. , Larson Eli J. , Zhu Yanlong , Brasier Allan R. , Jin Song , Ge Ying
Published: March 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes an extensively glycosylated surface spike (S) protein to mediate host cell entry and the S protein glycosylation is strongly implicated in altering viral binding/function and infectivity. However, the structures and relative abundance of the new O-glycans found on the S protein regional-binding domain (S-RBD) remain cryptic because of the challenges in intact glycoform analysis. Here, we report the complete structural characterization of intact O-glycan proteoforms using native top-down mass spectrometry (MS). By combining trapped ion mobility spectrometry (TIMS), which can separate the protein conformers of S-RBD and analyze their gas phase structural variants, with ultrahigh-resolution Fourier transform ion cyclotron resonance (FTICR) MS analysis, the O-glycoforms of the S-RBD are comprehensively characterized, so that seven O-glycoforms and their relative molecular abundance are structurally elucidated for the first time. These findings demonstrate that native top-down MS can provide a high-resolution proteoform-resolved mapping of diverse O-glycoforms of the S glycoprotein, which lays a strong molecular foundation to uncover the functional roles of their O-glycans. This proteoform-resolved approach can be applied to reveal the structural O-glycoform heterogeneity of emergent SARS-CoV-2 S-RBD variants, as well as other O-glycoproteins in general.
In vitroscreening of herbal medicinal products for their supportive curing potential in the context of SARS-CoV-2
Authors: Tran Hoai Thi Thu , Peterburs Philipp , Seibel Jan , Abramov-Sommariva D. , Lamy Evelyn
Published: March 2021

Background

Herbal medicinal products have a long-standing history of use in the therapy of common respiratory infections. In the COVID-19 pandemic, they may have the potential for symptom relief in non-severe or moderate disease cases. Here we describe the results derived byin vitroscreening of five herbal medicinal products with regard to their potential to i) interfere with the binding of the human Angiotensin-converting enzyme 2 (ACE2) receptor with the SARS-CoV-2 Spike S1 protein, ii) modulate the release of the human defensin HBD1 and cathelicidin LL-37 from human A549 lung cells upon Spike S1 protein stimulation and iii) modulate the release of IFN-γ from activated human peripheral blood mononuclear cells (PBMC). The investigated extracts were: Sinupret extract (SINx), Bronchipret thyme-ivy (BRO TE), Bronchipret thyme-primrose (BRO TP), Imupret (IMU), and Tonsipret (TOP).

Methods

The inhibitory effect of the herbal medicinal products on the binding interaction of Spike S1 protein and the human ACE2 receptor was measured by ELISA. The effects on intracellular IFN-γ expression in stimulated human PBMCs were measured by flow cytometry. Regulation on HBD1 and LL-37 expression and secretion was assessed in 25d long-term cultured human lung A549 epithelial cells by RT-PCR and ELISA.

Results

IMU and BRO TE concentration-dependently inhibited the interaction between spike protein and the ACE2 Receptor. However, this effect was only observed in the cell-free assay at a concentration range which was later on determined as cytotoxic to human PBMC. SINx, TOP and BRO TP significantly upregulated the intracellular expression of antiviral IFNγ from stimulated PBMC. Co-treatment of A549 cells with IMU or BRO TP together with SARS-CoV-2 spike protein significantly upregulated mRNA expression (IMU) and release (IMU and BRO TP) of HBD1 and LL-37 (BRO TP).

Conclusions

Thein vitroscreening results provide first evidence for an immune activating potential of some of the tested herbal medicinal extracts in the context of SARS-CoV-2. Whether these could be helpful in prevention of SARS-CoV-2 invasion or supportive in recovery from SARS-CoV-2 infection needs deeper understanding of the observations.
Practical Identifiability in the Frame of Nonlinear Mixed Effects Models: the Example of thein vitroErythropoiesis
Authors: Duchesne Ronan , Guillemin Anissa , Gandrillon Olivier , Crauste Fabien
Published: March 2021

Nonlinear mixed effects models provide a way to mathematically describe experimental data involving a lot of inter-individual heterogeneity. In order to assess their practical identifiability and estimate confidence intervals for their parameters, most mixed effects modelling programs use the Fisher Information Matrix. However, in complex nonlinear models, this approach can mask practical unidentifiabilities. Herein we rather propose a multistart approach, and use it to simplify our model by reducing the number of its parameters, in order to make it identifiable. Our model describes several cell populations involved in thein vitrodifferentiation of chicken erythroid progenitors grown in the same environment. Inter-individual variability observed in cell population counts is explained by variations of the differentiation and proliferation rates between replicates of the experiment. Alternatively, we test a model with varying initial condition. We conclude by relating experimental variability to precise and identifiable variations between the replicates of the experiment of some model parameters.
Embryonic requirements forTcf12in the development of the mouse coronal suture
Authors: Ting Man-chun , Farmer D’Juan T. , Teng Camilla S. , He Jinzhi , Chai Yang , Crump J. Gage , Maxson Robert E.
Published: March 2021

A major feature of Saethre-Chotzen syndrome is coronal craniosynostosis, the fusion of the frontal and parietal bones at the coronal suture. It is caused by heterozygous loss-of-function mutations in the basic HLH transcription factorsTWIST1andTCF12. While compound heterozygousTcf12; Twist1mice display severe coronal synostosis, the individual role ofTcf12has remained unexplored. Here we show that Tcf12 controls several key processes in calvarial development, including the rate of frontal and parietal bone growth, and the boundary between sutural and osteogenic cells. Genetic analysis supports an embryonic requirement forTcf12in suture formation, as combined deletion ofTcf12in the embryonic neural crest and mesoderm, but not in the postnatal suture mesenchyme, disrupts the coronal suture. We also detect asymmetric distribution of Grem1 + mesenchymal cells on opposing sides of the wild-type frontal and parietal bones, which prefigures later bone overlap at the sutures. InTcf12mutants, reduced asymmetry correlates with lack of bone overlap. Our results indicate a largely embryonic function of Tcf12 in controlling the rate and asymmetrical growth of calvarial bones and establishment of suture boundaries, which together ensure the proper formation of the overlapping coronal suture.
Toward an understanding of BPR perception in the construction industry: the employee attitude toward job enlargement and enrichment in Saudi Arabia
Authors: Hadidi Laith , Abzakh Ahmad
Published: March 2021

Purpose

Business process reengineering (BPR) is a management improvement tool that entails radical changes to organizations' core processes, culture and legacy systems. Although BPR initiatives are favored by many mangers, employees on the other hand, perceive BPR as a potential threat to lose their jobs. This research aims to enhance the employee perception toward BPR implementation in the construction industry as BPR asks for job enlargement (number of different tasks) and enrichment (degree of responsibility) and doesn’t target the workforce downsizing by itself.

Design/methodology/approach

The research is conducted in Saudi Arabia by involving experienced construction industry practitioners in a survey questionnaire and semi-structured interviews to gain an insightful perception toward BPR constituents. BPR asks for job enlargement (number of different tasks) and enrichment (degree of responsibility). The survey questionnaire is verified from the literature related to BPR and pilot study through experienced construction practitioners. The experts validated the findings.

Findings

The findings of this research reveal a general positive acceptance toward BPR constituents in construction industry. Jobs enrichment and enlargement should be approached: by integrating IT with business functions (especially communication); developing flexible management systems; and encouraging and empowering employees to generate value through their jobs with more delegated authority.

Originality/value

The work is one of the few studies to address the concept of Business Process Reengineering in the construction industry. We explore two research questions as detailed in the submission (BPR perception in the construction industry, and how to have a successful BPR by job enlargement and enrichment. The methods can be extended to other industries and in different parts in the world.
Nexus between distributed leadership, teacher academic optimism and teacher organisational commitment: a structural equation modelling analysis
Authors: Thien Lei Mee , Adams Donnie , Koh Hai Ming
Published: March 2021

Purpose

This study aims to investigate the relationships between distributed leadership, teacher academic optimism and teacher organisational commitment with the contextual influence of gender and teaching experience.

Design/methodology/approach

This study employed partial least squares structural equation modelling for data analysis. This study has selected 421 teachers from 18 secondary schools in Penang.

Findings

Distributed leadership has a positive direct effect on teacher academic optimism and organisational commitment. The relationship between distributed leadership and teacher academic optimism was stronger for male teachers and senior teachers who have more than ten years of teaching experience. However, gender and teaching experience have no significant moderating effects on the relationship between distributed leadership and teacher organisational commitment.

Research limitations/implications

The reason for the non-existent relationship between distributed leadership and teacher organisational commitment across gender and teaching experience remains unknown. In-depth investigation using interview method is required for further exploration.

Practical implications

This study complements and extends prior research on the relationships between distributed leadership, teacher organisational commitment and teacher academic optimism by providing evidence from Malaysia on how they contribute to the organisational conditions of their school.

Originality/value

This study has its originality in investigating the relationships between distributed leadership, teacher organisational commitment and academic optimism with the contextual influence of gender and teaching experience in the non-western society.
Classification and categorization of Brazilian agricultural startups (Agtechs)
Authors: Bertucci Ramos Paulo Henrique , Pedroso Marcelo Caldeira
Published: March 2021

Purpose

This paper aims to identify and analyze the agtech classification and categorization systems in the Brazilian context.

Design/methodology/approach

The systematic literature review (SLR) was carried out according to the protocol of Kitchenham and Charters (2007). The classification systems found in literature were evaluated using the thinking aloud protocol, as proposed by Ericsson and Simon (1993). The responses obtained were evaluated through lexicographic analysis, described by Bécue-Bertaut (2019) and content analysis, described by Bardin (2011).

Findings

SLR identified four agtech classification systems. The model proposed by Dias, Jardim, and Sakuda (2019) was the one with the highest adherence to classify Brazilian agtechs. From the analysis of the systems found in literature, the authors proposed a new categorization model of agricultural startups (agtechs).

Research limitations/implications

The study has limitations in relation to the theoretical and empirical validation of the model proposed by the authors. This limitation can be the subject of subsequent research.

Practical implications

The SLR study considers the evolution of the classification systems of a new agribusiness reality, the agtechs. In addition, there is a practical contribution in proposing a new classification system that attempts to address some of the limitations found in previous studies.

Originality/value

Agtechs are startups focused on developing solutions for agriculture and have shown a significant increase in recent years. However, there are few studies focused on this type of company. Even rarer are the studies that seek to classify and categorize them. The present work opens the horizon for future studies focused on this new reality.
Reliability analysis on the train control system in the CTCS-3 operating mode
Authors: Shi Lijuan , Wang Jian
Published: March 2021

Purpose

This paper aims to study the reliability of the high-speed train operation control system in the Chinese Train Control System Level 3 (CTCS-3) operating mode.

Design/methodology/approach

Dynamic fault tree and Bayesian network method are adopted to analyze the reliability and weakness of the CTCS-3 system.

Findings

First, a physical architecture and data flow diagram of the CTCS-3 system are established according to the typical structure and functions of the CTCS-3 system. Second, the dynamic fault tree of the CTCS-3 system is constructed. Considering the prior probability of the bottom event and the existence of dynamic redundancy, the dynamic fault tree is transformed into a Bayesian net. The reliability of the CTCS-3 system is carried out based on the prior probability and the weakness that affects the reliability of the system based on the posterior probability is also analyzed by the Bayesian network. Finally, it is disclosed that the impact of the on-board subsystem on the reliability of the CTCS-3 system is generally greater than that of the ground subsystem. The two weakest modules in the onboard subsystem are the driver-machine interface (DMI) and balise transmission module (BTM) and the weakest one in the ground subsystem is Balise. The analysis results are generally consistent with the malfunctions in the field operation of China’s high-speed railway.

Originality/value

(1) By reasoning, the reliability of the train operation control system in the CTCS-3 operating mode meets the standard requirements.

(2) Through backward reasoning, it is found that the failure of the onboard subsystem leads to a greater probability of failure of the train control system.

(3) The DMI, BTM and automatic train protection computer unit modules are weak components in the onboard subsystem. Vital digit input&output, train interface unit and train security gateway are rarely involved in previous research, the result in this paper shows that these three modules are also weak components in the subsystem, which requires attention.
Misunderstanding on germination sensu stricto leads us to a false positive germination‐dormancy balance in diaspores of Paepalanthus chiquitensis Herzog (Eriocaulaceae), a threatened everlasting flowering species
Authors: Gonçalves‐Magalhães Carollayne , de Santana Denise G. , Ribeiro‐Oliveira João Paulo
Published: March 2021

Although germination sensu stricto and germination–dormancy balance are essential to each other, few reports demonstrate the effects of their relationship on patterns of seed–seedling transition. We studied this relationship by using diaspores of Paepalanthus chiquitensis, a threatened everlasting flowering species. We assessed three aspects: (a) water dynamics in germinating diaspores, (b) thermal stimulation (35, 40, 50, 60 and 70°C for 30 min) and (c) imbibition (4 hr) in growth stimulators (100, 200 or 300 mg · L−1 GA3; 0.1% KNO3). Our findings demonstrate that there are no barriers in the diaspore for diffusion. Additionally, there is high variability in diaspore permeability, and the germination of the species has two steps divided into five stages. These stages were defined by inflections on velocity in water dynamics, which ranged from −0.05 to 0.05 g · hr−1, where only the last stage (Phase V) is associated with the second step of germination sensu stricto. The imbibition phase was the shortest germination phase (1.3 hr), whereas the predominantly biochemical phase was the longest (5 days after sowing [DAS]). Germinability was high (77.5–86.5%), with high daily embryo protrusion (2.46–3.03 diaspores · day−1). Protocorm emergence marked the end of the first step of germination sensu stricto (9 DAS), and first protocorm rupture (11 DAS) marked the end of the second step. The growth stimulus only concentrated the germination process, showing that the diaspores do not have primary dormancy. Knowing these diaspores’ peculiarities during germination sensu stricto avoids a false positive statement on the existence of diaspore dormancy.
DIFFERENTIATED CITIZENSHIP: The Everyday Politics of the Urban Poor in Kathmandu, Nepal
Authors: Butcher Stephanie
Published: March 2021

This article explores the everyday politics through which citizenship is negotiated by diverse residents, analysing the case of Bansighat, an informal settlement in Kathmandu, Nepal. It focuses on both the collective tactics of the Nepali women's federation of the urban poor—Nepal Mahila Ekata Samaj—as well as the quotidian practices of diverse residents around water and sanitation. This analysis reveals the variegated politics through which citizenship plays out—reflecting complex interactions between wider processes of urban transformation in Kathmandu, localized socio‐spatial conditions of Bansighat and long‐standing social relations in Nepali society. The empirical findings help to make more explicit the politics through which some residents are able to capitalize and transform diverse tenure and infrastructural practices into a broader sense of legitimacy or belonging in the city, while simultaneously engendering exclusions for others. This article accordingly reflects on how broader class and ethnic power relations play out through everyday citizenship negotiations, generating differentiated experiences of citizenship for diverse individuals.
Stock and Bond Return Comovement as a Different Way to Assess Information Content: The Case of Debt Covenant Violation Disclosures
Authors: Griffin Paul A. , Lont David H. , Purdon Kurt
Published: March 2021

We propose a supplementary way to assess the information content of a financial statement disclosure based on the comovement of asset returns in different markets in response to information that has price implications for both. The influence of a signal that strongly influences at least two asset markets measures a dimension of information content less clearly reflected in single‐market responses. We apply our method to debt covenant violation (DCV) disclosures. These are the outcome of a debt renegotiation when the covenant promises in a debt agreement to manage the agency costs of debt are broken. We find that stock and bond return comovement is highest one day before DCV disclosure and differs depending on whether the debt covenant is waived or not waived. We find that stock and bond return comovement in the days following a DCV disclosure decreases more for non‐waiver disclosures than for waiver disclosures. This supports the theory that a non‐waiver outcome shifts control rights and bargaining power to the creditors. Consistent with this theory, single‐market tests show that bonds with a non‐waiver disclosure versus a waiver disclosure earn positive excess returns following a DCV disclosure whereas the reverse is true for stocks.
New species‐group of brachypterous Idris Förster, 1856 s.l. (Hymenoptera: Platygastridae s.l.) from the Oriental region
Authors: Kamalanathan Veenakumari , Austin Andrew D
Published: March 2021

Members of the cosmopolitan wasp tribe Baeini (Platygastridae s.l.) are obligate endoparasitoids of spider eggs. The group is estimated to have well over 2000 species globally, approximately 80% of which are undescribed. Most species belong to the genus Idris Förster s.l., a megadiverse group which is probably paraphyletic without the inclusion of a number of smaller genera. The group has resisted phylogenetic analysis using morphology largely due to convergence associated with reductional character states or, in the case of molecular analysis, insufficient taxon sampling and markers. To make any headway in understanding the diversity and relationships within the tribe, and particularly for the genus Idris, a pragmatic approach is to describe species groups that can be later incorporated into a broader sampling of taxa for molecular analysis. In taking this approach, we describe two new species from the Oriental region (India) with brachypterous females, Idris benaka sp. nov. and Idris samueli sp. nov., which are assigned to a new species group, the ‘benaka‐group’. These two species are morphologically similar to a number of undescribed Idris from Australia and southern Africa which, if related, point to a possible circum‐Indian Ocean distribution for this species group. In addition, we also discuss the make‐up and relationships of Idris, and the nature of wing reduction in the Baeini.
The MIS 3–2 environments of the middle Kolyma Basin: implications for the Ice Age peopling of northeast Arctic Siberia
Authors: Chlachula Jiri , Cheprasov Maksim Y. , Novgorodov Gavril P. , Obada Theodor F. , Little Edward
Published: March 2021

The Kolyma region is historically famous for the unique finds of large Pleistocene fauna, yet, until very recently, absent of the time‐corresponding occupation sites. Quaternary geology and palaeontology investigations (2013–2019) in the middle reaches of the Kolyma River (NE Yakutia) have delivered new evidence on the Last Glacial (MIS 4–2) to Early Holocene sub‐arctic ecosystems and the past landscape dynamics retrieved from the fossiliferous bodies exposed from thawed grounds. The palaeoecology multi‐proxies from the MIS 3 (55–24 ka) cryolithic formations document riparian, larch‐dominated northern forests and open parklands with backwater channels, marshlands and lakes. The abundant skeletal remains of Pleistocene ungulates and carnivores, as well as relic flora point to long‐term biomass‐rich interstadial ecosystems and favourable Palaeolithic occupation habitats. Utilized animal bones, worked mammoth ivory and stone tools show the presence of pre‐modern humans in the northeast Russian Arctic >45 000 years ago. Flaked mammoth tusks suggest persistence of settlement during the Last Glacial Maximum in xeric and extremely cold (sub)arctic tundra. The postglacial climate shifts triggered major environmental and hydrological transformations. The final Pleistocene/Early Holocene warming brought restructuring of the Last Ice Age landscape and vanishing of the periglacial tundra‐steppe replaced by the present‐day larch‐dominated Siberian taiga. The mid‐Last Glacial human ecology records from the geographical limits of northeast Siberia have fundamental relevance for the reconstructions of the time trajectories and the natural conditions of peopling of Beringia.
Esophageal varices: A rare non‐cardiac finding in echocardiography
Authors: Maximo José , de Carvalho Daniel Seabra , Duarte Ana , Pinho Paulo , Almeida Jorge , Maciel João
Published: March 2021

A 43‐years‐old patient with hepatitis C and HIV co‐infection was referred to debridement of a left sternoclavicular septic arthritis. Due to suspicion of endocarditis, the patient underwent transthoracic echocardiogram which revealed an mass posterior to left atrium and descending aorta. A thoracic computed tomography revealed esophageal varices. Transesophageal echocardiogram was not performed. The patient has progressed favorably.
Early infection by Phytophthora agathidicida up‐regulates photosynthetic activity in Agathis australis seedlings
Authors: D'Souza Kimberley D. , Scott Peter , Williams Nari , Bellgard Stanley E. , Bader Martin K.‐F.
Published: March 2021

New Zealand kauri (Agathis australis) trees are culturally, socially and ecologically significant within northern New Zealand's nutrient‐poor podocarp forest ecosystems. Phytophthora agathidicida is an aggressive oomycete pathogen, capable of killing A. australis across its ecological range, causing the disease known as kauri dieback. The pathogen, like many other forest Phytophthora species, commences as a fine root rot which progresses to collar rot and resinous cankers on the lower trunk. In this study, we investigated the eco‐physiological and fine root responses of kauri to infection by P. agathidicida and tested whether the foliar application of micronutrients (manganese and zinc combined, iron alone, or a trace element mix) affects dieback disease expression. Fortnightly assessments of chlorophyll‐a‐fluorescence were conducted over 12 weeks, and fine root length and tip numbers were recorded at the end of the experiment. None of the micronutrient treatments had a significant physiological effect regardless of pathogen infection. However, contrary to expectations, pathogen infection caused a significant upregulation in photosynthetic activity over time, as the electron transport rate of infected plants was approximately 26% higher than that of control plants at the end of the trial. These results indicate that an increase in the strength of the below‐ground carbon sink through pathogen consumption of labile carbohydrates (sugars), together with pathogen‐induced root damage, triggered upregulation of photosynthesis in the seedlings. Understanding how P. agathidicida infection affects the physiology and resource allocation in kauri is critical to determining the disease aetiology and management options.
Long‐term tolerability of phosphodiesterase‐5 inhibitors in pulmonary hypertension of sickle cell disease
Authors: Cramer‐Bour Cassondra , Ruhl Amy Parker , Nouraie Seyed Mehdi , Emeh Robert O. , Ruopp Nicole F. , Thein Swee Lay , Weir Nargues A. , Klings Elizabeth S.
Published: March 2021

Objectives

Sickle cell disease‐related pulmonary hypertension (SCD‐PH) is a complex disorder with multifactorial contributory mechanisms. Previous trials have evaluated the efficacy of pulmonary arterial hypertension (PAH) therapies in SCD‐PH with mixed results. We hypothesized that a subset of patients with right heart catheterization (RHC) confirmed disease may benefit from PAH therapy.

Methods

We performed a retrospective chart review of patients with SCD‐PH diagnosed by RHC who were treated with phosphodiesterase 5 inhibitor (PDE5‐I) therapy for ≥4 months between 2008 and 2019 at two institutions.

Results

Thirty‐six patients were included in the analysis. The median age (IQR) upon PDE5‐I initiation was 47.5 years (35‐51.5 years); 58% were female and twenty‐nine (81%) had HbSS disease. Of these, 53% of patients had a history of acute chest syndrome, 42% had a history of venous thromboembolism, and 38% had imaging consistent with chronic thromboembolic PH. Patients were treated for a median duration of 25 months (IQR 13‐60 months). Use of PDE5‐I was associated with a significant improvement in symptoms as assessed by NYHA Class (P = .002).

Conclusions

In SCD patients with PH defined by RHC, PDE5‐I therapy was tolerated long‐term and may improve physical activity.
A thioacetamide interlayer anchoring TiO2 and (FAPbI3)1−x(MAPbBr3)x for high‐performance perovskite solar cells
Authors: Wang Jingjing , Chen Yumin , Zhao Andi , Guo Minghuang , Zhu Jingwei , Li Yafeng , Wei Mingdeng
Published: March 2021

In the perovskite solar cells (PSCs), traps of the perovskite film or interface are the research focus, which can severely hinder charge transfer and benefit charge recombination, thus weakening the photoelectric performance of the devices. Herein, a Thioacetamide (TAA) interfacial layer is used to passivate the traps of PSCs. Comparing to the control device (17.65%), the TAA‐based solar cells can achieve an enhanced efficiency of 19.14%. It is found that the passivation caused by TAA occurs through the interactions of sulfur in TAA with undersaturated Pb in perovskite and Ti4+ in TiO2, resulting in a faster and more efficient charge transfer and a greatly reduced trap density from 3.36 × 1016 cm−3 to 1.93 × 1016 cm−3. It is shown that the modification method using TAA may be helpful for passivating traps and obtaining excellent photoelectric properties of PSCs.
Comorbidities in patients with chronic hepatitis C and hepatitis B on hemodialysis
Authors: Hsu Po‐Yao , Wei Yu‐Ju , Liang Po‐Cheng , Lee Jia‐Jung , Niu Sheng‐Wen , Huang Jiun‐Chi , Hsu Cheng‐Ting , Jang Tyng‐Yuan , Huang Ching‐I , Lin Yi‐Hung , Hsieh Ming‐Yen , Hsieh Meng‐Hsuan , Chen Szu‐Chia , Dai Chia‐Yen , Lin Zu‐Yau , Chen Shinn‐Cherng , Huang Jee‐Fu , Chang Jer‐Ming , Yeh Ming‐Lun , Huang Chung‐Feng , Chiu Yi‐Wen , Hwang Shang‐Jyh , Chuang Wan‐Long , Yu Ming‐Lung
Published: March 2021

Background and Aim

Hemodialysis patients are at increased risk of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. Both HBV and HCV infections lead to risks of end‐stage liver diseases and extrahepatic manifestations. This study aimed to investigate hepatic and extrahepatic comorbidities in hemodialysis patients with HBV or HCV infections compared with those without viral hepatitis.

Methods

A total of 1910 hemodialysis patients, including 159 HCV viremic patients (HCV group), 217 seropositive for HBV surface antigen (HBsAg, HBV group) and 1534 seronegative for both anti‐HCV and HBsAg (non‐B and non‐C [NBNC] group), from 23 hemodialysis centers were enrolled. Comorbidities were classified into 10 categories by the International Classification of Diseases‐10th Revision.

Results

Among the 1910 patients, the mean age was 64.6 years, and 52.7% were male patients. A total of 1834 (96%) patients had at least one comorbidity, and the mean number of comorbidities was 2.9 ± 1.5 per person. The three most common comorbidities were hypertension, diabetes, and ischemic heart diseases. The mean number of comorbidities per person was significantly higher in the HCV group (3.3 ± 1.7) than in the HBV (2.7 ± 1.5, P < 0.001) and NBNC groups (2.9 ± 1.5, P = 0.004), mainly due to the higher prevalence of ischemic heart disease, respiratory disorders, and mental/behavioral disorders. The HBV and NBNC groups exhibited comparable burdens of comorbidities.

Conclusions

Hemodialysis patients had a high prevalence of multiple comorbidities. Hemodialysis patients with HCV exhibited a higher burden of comorbidities, especially ischemic heart diseases, respiratory disorders, and mental/behavioral disorders, than HBV and NBNC patients did.
Employment polarization in regional labor markets: Evidence from the Netherlands
Authors: Terzidis Nikolaos , Ortega‐Argilés Raquel
Published: March 2021

This study investigates the existence and extent of employment polarization in the Netherlands between 1999 and 2012. We first determine an asymmetrically polarized employment growth nationally and in local labor markets, especially among young workers. Second, our dynamic panel system‐generalized method of moments instrumental variable approach documents that employment polarization is the combined outcome from the interplay between technology and international trade. Our analysis also uncovers novel insights considering the regional determinants of employment polarization; specifically, we demonstrate that employment growth is more likely to polarize in less densely populated regions and those with higher initial specialization in medium‐ and high‐skilled sectors.
Natural disasters, firm survival, and growth: Evidence from the Ise Bay Typhoon, Japan
Authors: Okubo Toshihiro , Strobl Eric
Published: March 2021

This paper investigates the damage impact of the 1959 Ise Bay Typhoon on firm survival and survivor performance in Nagoya City, Japan. We combine firm‐level data with a local damage proxy storm surge‐induced flooding. We find that firms in retail and wholesale were less and those in manufacturing more likely to survive after being flooding. There was some evidence of spillover effects from nearby regions on firm exit. Surviving firm performance was heterogeneous across sectors in that some (manufacturing and construction) upgraded and others (retail and wholesale) their capital. Indirect impacts from nearby regions were both positive and negative, contingent on the sector of operation.
Hyperglycemia accelerates inflammaging in the gingival epithelium through inflammasomes activation
Authors: Zhang Peng , Lu Boyao , Zhu Rui , Yang Dawei , Liu Weiqing , Wang Qian , Ji Ning , Chen Qianming , Ding Yi , Liang Xing , Wang Qi
Published: March 2021

Background and Objective

Diabetes accelerates inflammaging in various tissue with an increase in senescent cell burden and senescence‐associated secretory phenotype (SASP) secretion, which is a significant cause of tissue dysfunction and contributes to the diabetic complications. Recently, inflammasomes are thought to contribute to inflammaging. Here, utilizing diabetic models in vivo and in vitro, we investigated the potential association between hyperglycemia‐induced inflammaging and gingival tissue dysfunction and the mechanism underlying inflammasome‐associated inflammaging.

Materials and Methods

Gingival epithelium and serum were collected from control and diabetic patients and mice. The expression of p16, p21, and inflammasomes in the gingival epithelium, SASP factors in serum, and the molecular factors associated with gingival epithelial barrier function were assessed. Human oral keratinocyte (HOK) was stimulated with normal and high glucose, and pre‐treated with Z‐YVAD‐FMK (Caspase‐1 inhibitor) prior to evaluating cellular senescence, SASP secretion, and inflammasome activation.

Results

In vivo, hyperglycemia significantly elevated the local burden of senescent cells in the gingival epithelium and SASP factors in the serum and simultaneously reduced the expression levels of Claudin‐1, E‐cadherin, and Connexin 43 in the gingival epithelium. Interestingly, the inflammasomes were activated in the gingival epithelium. In vitro, high glucose‐induced the inflammaging in HOK, and blocking inflammasome activation through inhibiting Caspase‐1 and glucose‐induced inflammaging.

Conclusions

Hyperglycemia accelerated inflammaging in the gingival epithelium through inflammasomes activation, which is potentially affiliated with a decline in the gingival epithelial barrier function in diabetes. Inflammasomes‐related inflammaging may be the crucial mechanism underlying diabetic periodontitis and represents significant opportunities for advancing prevention and treatment options.
Oral appliances in the management of neuropathic orofacial pain: A retrospective case series
Authors: Bavarian Roxanne , Khawaja Shehryar N. , Treister Nathaniel S.
Published: March 2021

Objective

Neuropathic orofacial pain disorders are frequently managed with topical or systemic medications that carry a risk of dangerous side effects such as drowsiness, disorientation, and/or physical addiction. The aim of this paper is to report the use of neurosensory oral appliances as a safe means of providing symptomatic relief for neuropathic orofacial pain.

Study design

This is a retrospective chart review of patients with diagnoses of persistent idiopathic facial pain (PIFP), painful post‐traumatic trigeminal neuropathy (PTTN), or an oral dysesthesia, who utilized neurosensory appliances with or without the use of topical anesthetic gel.

Results

Eleven patients were identified. Eight patients (62.5%) found benefit with the neurosensory appliance alone, and three patients (37.5%) found relief with the addition of lidocaine 2% gel. All patients reported >50% resolution of their symptoms, with three (37.5%) reporting complete resolution. Seven patients maintained follow‐up ≥3 months, with efficacy lasting for a range of at least 3–8 months.

Conclusion

Oral neurosensory appliances, whether used alone as a physical barrier or as a vehicle to deliver topical anesthetic, represent a safe and effective modality for the management of neuropathic orofacial pain disorders. Additional studies are needed to assess long‐term efficacy.
Underground and Out of Sight
Authors: Kosowatz John
Published: March 2021

Workers recently finished the last piece of tunnel for Kuala Lumpur’s second metro line, capping a program where autonomous tunneling machines have been operating remotely since 2016. Getting to that point took a poke by a seasoned tunneling director and TBM manager who found an unlikely duo of young, computer savvy, code-writing engineers who brought steering, advancement, excavation, and slurry operations under one operating system.
Shoring Up the Front Lines
Authors: Siegel R.P.
Published: March 2021

When offices and workplaces reopen, HVAC systems will be the first line of defense against spread of viruses like the coronavirus. The technology to provide defense against microbes already exists. Unfortunately, the urgency to deploy these systems has not existed before now.
The Determination of the Expansion Forces in Piping by Model Test
Authors: Semar Harold W.
Published: March 2021

The paper describes apparatus for testing models of piping installations to determine the forces set up in the full-size installation due to expansion. The method consists in fixing one end of the model in a slide which can be moved a measured amount, and measuring the forces at the other end by means of a fixture which holds that end rigidly in place and permits measurement of six forces in three coordinate planes, which are the equivalent of forces in coordinate directions plus moments in coordinate planes. The slide of the movable end is placed so that its direction of motion coincides with the direction of the pipe expansion.

A complete example is given showing the steps in determining the end reactions of an inlet pipe for a steam turbine.
The Distribution of Load on the Threads of Screws
Authors: Goodier J. N.
Published: March 2021

The distribution of load on the threads of screws and the types of deformation affecting it have been investigated by means of extensometer measurements made on the outside of the nut. The types of deformation characteristic of concentrations of load on different parts of the thread were found by using a bolt carrying only a single turn of thread. At low loads the deformations of nuts with complete bolts closely resemble the effects of the artificial concentration of load on the base part of the thread, whereas there are marked contrasts with the effects of loads concentrated at the middle or at the free end. At higher loads a more uniform distribution is indicated. Similar conclusions follow from the application of an approximate method for deducing the distribution from the deformation measurements.

It is shown that the distribution is governed by (a) stretch and compression in bolt and nut, respectively, which are primarily responsible for concentration at the base; and (b) by bending of the thread, circumferential stretch (at the base), and contraction (near the free end) of the nut wall, which have comparable effects in reducing the concentration.
Stresses and Deflections of Three-Dimensional Pipe Bends
Authors: Poritsky H. , Snively H. D.
Published: March 2021

Many treatments of stresses of three-dimensional pipe bends have appeared in recent times. While the calculation of these stresses and deflections is perfectly straightforward, it is still very complicated. It is believed that the analogy to which attention is called in this paper should be of considerable assistance in simplifying these calculations by pointing out their similarity to familiar dynamical concepts involving products and moments of inertia and moments of momentum.
Measurement of Impact Strains by a Carbon-Strip Extensometer
Authors: Fanning R. , Bassett W. V.
Published: March 2021

This paper describes a method of experimentally ascertaining the actual stress-time curve in a mechanical part subjected to an impact blow. The apparatus consists of a resistance strain gage in conjunction with a high-speed recording oscillograph, the combination being sufficiently rapid in response to record strain variations occurring within a few microseconds. Consequently, the strains during impact are recorded with sufficient accuracy for detailed analysis.

Longitudinal strain waves in long bars striking end to end have been subjected to theoretical analysis and have served as a subject for testing of the apparatus. The theory is reviewed in this paper, and computed results based thereon are compared with experimental data. The agreement is shown to be satisfactory, the form being as predicted and the magnitude within a few per cent of the computed value.

The strain waves and reflections occurring in this simple case are surprisingly complex. An investigation of other impact problems by this method, such as the correlation of standard impact tests of materials, might well yield information of considerable value.
The Normal Modes of Vibrations of Beams Having Noncollinear Elastic and Mass Axes
Authors: Garland Clyne F.
Published: March 2021

This analysis deals with vibration characteristics of cantilever beams in which the longitudinal axis, passing through the mass centers of the elementary sections, is not collinear with the longitudinal axis about which the beam tends to twist under the influence of an applied torsional couple. Expressions are derived from which the natural frequencies and normal modes of vibration of such a beam can be determined. The Rayleigh-Ritz method is employed to determine the frequencies and amplitude ratios. Following the development of the general expressions, more specific equations are derived which express the natural frequencies and relative amplitudes of motion in each of two normal modes of vibration.

The theoretical relationships of the several physical properties of the beam to the natural frequencies of vibration are shown graphically. Finally a numerical example is presented for a particular beam, and the computed natural frequencies and normal modes are compared with those determined experimentally.
Strengthening Cylindrical Tanks of Variable Thickness Under External Pressure by Circular Stiffening Rings
Authors: Biezeno C. B. , Koch J. J.
Published: March 2021

In a previous paper the authors discussed the buckling of a cylindrical tank of variable thickness under external pressure, and they developed a method by which the factor of safety against buckling was derived in numerical terms.

This present paper deals with the strengthening of a tank whose factor of safety is insufficient. Obviously, great help may be expected from one or two stiffening circular rings, adjusted in the upper part of the tank, where the thickness of the shell is small. The authors show how to calculate such rings.
On the Zeros of an Undamped Three Degrees-of-Freedom Flexible System
Authors: Rath Siddharth , Cui Leqing , Awtar Shorya
Published: March 2021

This paper presents an investigation of zeros in the SISO dynamics of an undamped three degrees-of-freedom (3DOF) linear time invariant (LTI) flexible system. Of particular interest are non-minimum phase zeros, which severely impact closed-loop performance. This study uses modal decomposition and zero loci to reveal all types of zeros—marginal minimum phase (MMP), real minimum phase (RMP), real non-minimum phase (RNMP), complex minimum phase (CMP), and complex non-minimum phase (CNMP)—that can exist in the system under various parametric conditions. It is shown that if CNMP zeros occur in the dynamics of an undamped LTI flexible system, they will always occur in a quartet of CMP-CNMP zeros. Consequently, the simplest undamped LTI flexible system that can exhibit CNMP zeros in its dynamics is a 3DOF system. Motivated by practical examples of flexible systems that exhibit CNMP zeros, the undamped 3DOF system considered in this paper comprised one rigid-body mode and two flexible modes. For this system, the following conclusions are mathematically established: (1) This system exhibits all possible types of zeros, (2) The precise conditions on modal frequencies and modal residues associated with every possible zero provide a mathematical formulation of the necessary and sufficient conditions for the existence of each type of zero, and (3) Alternating signs of modal residues is a necessary condition for the presence of CNMP zeros in the dynamics of this system. Conversely, avoiding alternating signs of modal residues is a sufficient condition to guarantee the absence of CNMP zeros in this system.
Design of a Tip Appendage for the Control of Tip Leakage Vortices in Axial Flow Fans
Authors: Meyer Thomas O. , van der Spuy Sybrand J. , Meyer Christiaan J. , Corsini Alessandro
Published: March 2021

This article reports on numerical investigations of passive control techniques used for the performance enhancement of a large diameter axial flow cooling fan through modification of the blade tip geometry. Using open-source software, a novel meshing strategy is developed to carry out both steady and unsteady numerical computations of a periodic section of an axial flow fan. Analyzing the flow near the blade tip with a reduction in tip clearance, two predominant flow phenomena are identified. These two flow phenomena are further investigated with the aim of controlling them through implementation of a tip appendage design. Both introduced end-plate designs indicate effective control of each relevant flow phenomena. The constant thickness (CT) end-plate design is found to increase all fan performance characteristics at lower than design point (DP) flowrates, while increasing the fan’s peak efficiency plateau toward the rotor stall margin. However, none of the CT end-plate designs are able to improve the fan’s performance characteristics at its DP. The introduction of a novel trailing-edge (TE) end-plate design is found to increase all fan performance characteristics across the entire evaluated stable operating range, with an indicated increase of 37.3 percent in total-to-static pressure rise and a 2.9 percentage point increase in total-to-static efficiency at the fan’s DP flowrate. The aerodynamic performance results attest to the associated benefits of the investigated passive control techniques.
Ultrasmooth cobalt films on SiO2 by chemical vapor deposition using a nucleation promoter and a growth inhibitor
Authors: Zhang Zhejun V. , Liu Sumeng , Girolami Gregory S. , Abelson John R.
Published: March 2021

Very smooth thin films of Co are deposited on SiO2 by chemical vapor deposition from the precursor dicobalt octacarbonyl Co2(CO)8 by augmenting the process conditions in two ways: (1) pretreating the surface to promote nucleation and (2) adding a coflow of a growth inhibitor. The surface pretreatment involves brief exposure of the SiO2 surface at 70 °C to a tetrakis(dimethylamido) metal complex M(NMe2)4, where M = V, Ti, or Hf. This pretreatment affords a self-limiting, submonolayer coverage of a metal-containing intermediate. When the pretreated surface is then exposed to 0.025 mTorr of the Co2(CO)8 precursor, nucleation occurs to afford a high density (1 × 1012 cm2) of nanoscale islands; the rms surface roughness for a sample with an areal density of 100 Co atoms/nm2 is 1.0 nm. Comparisons show that the M(NMe2)4 pretreatment has three benefits: it accelerates the nucleation process, it increases the nucleation density by about a factor of 3, and it reduces the surface roughness by about a factor of 2. The rms surface roughness of a sample with ∼100 Co atoms/nm2 can be further reduced to only 0.3 nm by adding up to 4 mTorr of ammonia NH3 to the feed gas along with the Co2(CO)8 precursor. Ammonia serves as a growth inhibitor that reduces the steady-state growth rate of Co by a factor of 4. This slower growth allows additional nucleation to occur on bare areas, and the growth of these nuclei affords coalescence with a smaller roughness.
Supplemental Material: Geology of Central Park, Manhattan, New York City, USA: New geochemical insights
Authors: Jaret Steven , al. et
Published: March 2021

Map of field stops as a .kmz file