bluuebunny/crossref_metadata_2025 huggingface dataset:
Using a variable value of the fictitious radius to estimate fatigue life of notched elements
Authors: Robak Grzegorz
Published: July 2020

The article discusses the problem related to estimating fatigue life of elements containing stress concentrators. The algorithm for estimating fatigue life presented in this work uses a fictitious ray based on the Neuber method. The proposed algorithm takes into account the variability of microstructural length, which depends on the number of failure cycles. The function thus obtained can be used to select the appropriate value for this length, which simplifies the calculation procedure needed to estimate fatigue life. In addition, this work includes an analysis of the impact of variable cutout geometry on the value of the support coefficient. As a result, it was possible to extend the application of this concept to lower fatigue life values and to structural elements with different notch geometries. The method was verified by performing experiments using elements made of three steel grades. A good correlation between calculation and experimental results was obtained.
Health literacy and COVID‐19
Authors: Spring Hannah
Published: July 2020

In early 2020, the world experienced an unprecedented health crisis. When the pandemic of coronavirus was declared by the World Health Organization, it brought with it sudden and dramatic changes to everyday life. In the UK, the key message from the Government was to ‘Stay at home, protect the NHS, save lives’, sending out a clear warning that failing to stay at home would put other lives and the ability of the NHS to cope at risk. This editorial discusses COVID‐19, how society responded and the vital role that health literacy plays in saving lives during a global health emergency.
Increase of insular exotic arthropod diversity is a fundamental dimension of the current biodiversity crisis
Authors: Borges Paulo A. V. , Rigal François , Ros‐Prieto Alejandra , Cardoso Pedro
Published: July 2020

A dramatic insect decline has been documented on the grasslands and forests of European or North American mainland. Yet, other parts of the world and other ecosystems remain much less studied with unknown patterns.

Using a unique time‐series dataset, we investigate recent trends on abundance and richness of arthropods sampled in Azorean native forest over 6 years (2013–2018).

We test the hypothesis that biodiversity erosion drivers are changing the diversity and relative species abundance structure (species abundance distribution, SAD) of endemics, native non‐endemics and exotic species over time. We also examine temporal trends in abundance for each individual species.

In contrast with mainland studies, we observed no decline in overall arthropod diversity, but a clear increase in the diversity of exotic arthropods and some evidence of a tendency for decreasing abundance for some endemic species. We also document stronger species turnover for exotic species, but no specific changes in the SAD.

We argue that many changes, particularly in unique systems such as islands, will be noticed not at the richness but mostly at compositional level. Special attention should be given to exotic species which are known to be one of the major drivers of biodiversity erosion on islands.
Preparation and physicochemical properties of edible films from gelatin and Andean potato (Solanum tuberosum Group Phureja) starch
Authors: Otálora María Carolina , Wilches‐Torres Andrea , Gómez Castaño Jovanny A.
Published: July 2020

A novel edible film formulation using native Andean potato starch (APS) and gelatin (G) was developed, and evaluated as a function of the APS/G ratio (3:1, 1:1, and 1:3). The films were physicochemically, structurally (FTIR and Raman), morphologically (SEM), thermally (DSC/TGA) and mechanically characterised. The addition of starch increased water resistance, clarity and thermal stability of the films. The SEM micrographs showed a heterogeneous surface and a compact structure. The films also showed low values for both tensile strength and elastic modulus. FTIR analysis revealed intermolecular interactions between the gelatin and starch. Edible film obtained in this work may have potential applications in many fields.
Factors influencing readiness for hospital discharge among patients undergoing laryngectomy
Authors: Zhao Huiling , Feng Xianqiong , Yu Rong , Gu Deying , Zhang Xiaoyan
Published: July 2020

Aim

To identify factors influencing readiness for hospital discharge among Chinese patients having undergone a laryngectomy and to provide evidence for developing future processes.

Background

Laryngectomy changes the functional and psychological state of laryngeal cancer patients considerably. However, influencing factors for discharge readiness among laryngectomy patients have hardly been investigated.

Methods

A descriptive, cross‐sectional design was used with Meleis' transitions theory as a guiding framework. This survey‐based study was performed with 212 laryngeal cancer patients undergoing laryngectomy at a regional tertiary medical centre between August 2012 and September 2013.

Results

Quality of discharge teaching and having a designated caregiver after discharge were found to influence patients' readiness for discharge.

Conclusion

Clinical interventions such as nursing assessment on discharge readiness, assistance to coordinate postdischarge support and individualized follow‐up planning should be integrated into future clinical processes in China. However, further investigations are needed to systematically align relevant results before clinical practices in Chinese settings are eventually changed.
Cardiac implantable electronic device placement following alcohol septal ablation for hypertrophic cardiomyopathy in the United States
Authors: Lam Matthew C. , Naidu Srihari S. , Kolte Dhaval , Kennedy Kevin , Feldman Dmitriy N. , Chu Antony F. , Abbott J. Dawn , Gordon Paul , Aronow Herbert D.
Published: July 2020

Background

Cardiac implantable electronic devices (CIED) are sometimes required after alcohol septal ablation (ASA) for hypertrophic cardiomyopathy (HCM). The primary objectives of this study were to characterize the incidence, timing, and predictors of CIED placement after ASA for HCM.

Methods

Patients were identified from the 2010–2015 Nationwide Readmissions Databases. Incidence, timing and independent predictors of CIED placement, as well as 30‐day readmission rates were examined.

Results

There were 1296 patients (national estimate = 2864) with HCM who underwent ASA. CIED were implanted in 322 (25% overall; 14% permanent pacemaker, 11% implantable cardioverter defibrillator) during the index hospitalization. Of these, 21%, 23%, 21%, and 18% occurred on postprocedure day 0, 1, 2, and 3, respectively. Only 17 (1.3%) patients underwent CIED implantation between discharge and 30‐day follow up. Independent predictors of index hospitalization CIED implantation included older age, diabetes, heart failure, nonelective index hospital admission and hospitalization at a privately owned hospital. Nonelective 30‐day readmission rates among those who did and did not undergo CIED placement during their index hospitalization, were 6.8% and 7.9%, respectively (p = .53); median time to readmission was also similar between groups.

Conclusions

One in four HCM patients undergoing ASA underwent CIED implantation during their index hospitalization; nearly 2/3rd during the first 48 h postprocedure. Private hospital ownership independently predicted CIED placement. More data are needed to better understand the unexpectedly high rates of CIED placement, earlier than anticipated timing of implantation and differential rates by hospital ownership.
Seasonal and developmental diet shifts in sympatric and allopatric intertidal gobies determined by stomach content and stable isotope analysis
Authors: Carbia Penelope S. , Brown Culum , Park Joo M. , Gaston Troy F. , Raoult Vincent , Williamson Jane E.
Published: July 2020

Resource partitioning facilitates the coexistence of sympatric species through spatial, temporal and/or trophic strategies. Fishes living in the intertidal zone demonstrate highly adaptive plastic behaviour, including resource partitioning, through spatial and temporal shifts in diet and microhabitat. Although intertidal fish assemblages are influenced by inter‐ and intraspecific competition, few studies have compared the extent of resource partitioning between sympatric species in the context of trophic niche plasticity. Here we used complementary approaches, stomach content and stable isotope (δ13C and δ15N) analyses, to evaluate seasonal and developmental shifts in trophic niche position in two sympatric (Favonigobius lentiginosus and Bathygobius krefftii) and one allopatric (Bathygobius cocosensis) species of intertidal goby. The results indicate that resource partitioning in the two sympatric species varied with season, with almost no trophic niche overlap in summer to about ~30% overlap in winter. Also, evidence of dietary changes was found in B. cocosensis, which is likely associated with a shift in microhabitat and intraspecific competition. The findings highlight the temporal range of behavioural plasticity in trophic niche position of intertidal gobies, which likely has high adaptive value in the dynamic intertidal zone.
Risk stratification for gastric cancer after Helicobacter pylori eradication: A population‐based study on Matsu Islands
Authors: Chiang Tsung‐Hsien , Maeda Masahiro , Yamada Harumi , Chan Chang‐Chuan , Chen Sam Li‐Sheng , Chiu Sherry Yueh‐Hsia , Chen Yen‐Nien , Chou Yi‐Hsuan , Shieh Chun‐Fu , Liu Cheng‐Ying , Chiu Han‐Mo , Chiang Hung , Shun Chia‐Tung , Lin Ming‐Wei , Wu Ming‐Shiang , Lin Jaw‐Town , Chen Hsiu‐Hsi , Ushijima Toshikazu , Graham David Y. , Lee Yi‐Chia
Published: July 2020

Background and Aim

The reliable method to stratify the gastric cancer risk after Helicobacter pylori eradication remains an elusive goal.

Methods

Mass eradication of H. pylori began in 2004 in a high‐risk population. After eradication, a screening program involving first‐stage serological tests (pepsinogen‐I, pepsinogen‐II, H. pylori immunoglobin G, and gastrin‐17) and second‐stage endoscopic examination was launched in 2015–2018. Index lesions included gastric cancer or extensive premalignant lesions. We evaluated the performance of the serological tests to “rule in” and “rule out” the risk based on positive and negative likelihood ratios, respectively. The methylation levels of microRNA‐124a‐3 in the stomach were measured to indicate genetic damage.

Results

Among 6512 invited subjects, 3895 (59.6%) participated. Both gastrin‐17 and pepsinogen tests were normal in 3560 (91.4%) subjects; 206 (5.3%) gastrin‐17 and 129 (3.3%) pepsinogen tests were abnormal. Years after eradication, the severity of gastritis had fallen greatly, and extensive premalignant lesions or gastric cancer frequently occurred in newly non‐atrophic‐appearing mucosa. Pepsinogen testing could moderately predict atrophic gastritis (positive likelihood ratio: 4.11 [95% confidence interval: 2.92–5.77]; negative likelihood ratio: 0.14 [0.10–0.19]). Gastrin‐17 was not useful (0.66 and 1.20, respectively). However, pepsinogen testing poorly predicted the index lesions (2.04 [1.21–3.42] and 0.57 [0.34–0.95]). DNA methylation levels in the post‐eradication mucosa were more discriminative for predicting index lesions (3.89 [2.32–6.54] and 0.25 [0.15–0.42]).

Conclusions

After eradication, pepsinogen false‐negative results become more frequent because histology is improved but genetic damage may persist. Direct testing for genetic damage offers better discrimination.
Differences in muscle mechanics underlie divergent optimality criteria between feeding and locomotor systems
Authors: Granatosky Michael C. , Ross Callum F.
Published: July 2020

Tetrapod musculoskeletal diversity is usually studied separately in feeding and locomotor systems. However, direct comparisons between these systems promise important insight into how natural selection deploys the same basic musculoskeletal toolkit—connective tissues, bones, nerves, and skeletal muscle—to meet the differing performance criteria of feeding and locomotion. Recent studies using this approach have proposed that the feeding system is optimized for precise application of high forces and the locomotor system is optimized for wide and rapid joint excursions for minimal energetic expenditure. If this hypothesis is correct, then it stands to reason that other anatomical and biomechanical variables within the feeding and locomotor systems should reflect these diverging functions. To test this hypothesis, we compared muscle moment arm lengths, mechanical advantages, and force vector orientations of two jaw elevator muscles (m. temporalis and m. superficial masseter), an elbow flexor (m. brachialis) and extensor (m. triceps‐ lateral head), and a knee flexor (m. biceps femoris‐short head) and extensor (m. vastus lateralis) across 18 species of primates. Our results show that muscles of the feeding system are more orthogonally oriented relative to the resistance arm (mandible) and operate at relatively large moment arms and mechanical advantages. Moreover, these variables show relatively little change across the range of jaw excursion. In contrast, the representative muscles of the locomotor system have much smaller mechanical advantages and, depending on joint position, smaller muscle moment arm lengths and almost parallel orientations relative to the resistance arm. These patterns are consistent regardless of phylogeny, body mass, locomotor mode, and feeding specialization. We argue that these findings reflect fundamental functional dichotomies between tetrapod locomotor and feeding systems. By organizing muscles in a manner such that moment arms and mechanical advantage are relatively small, the locomotor system can produce broad joint excursions and high angular velocities with only small muscular contraction. As such, the anatomical organization of muscles within the limbs allows striding animals to move relatively rapidly and with minimal energetic expenditure. In contrast, the anatomical configuration of muscles in the feeding system, at least m. superficial masseter and m. temporalis, favors their force‐producing capacity at the expense of excursion and velocity.
Caring as an Organizing Principle: Reflections on Ethnography of and as Care
Authors: Ortiz Casillas Samantha
Published: July 2020

This essay is a personal reflection – what Van Maanen (2011) calls a ‘confessional tale’ – about my first experience as an ethnographer. It is a reflection on the four months I spent researching a group of young activists who organized for a political campaign in Mexico City. In particular, it describes how—while observing their everyday lives and work—I came to develop strong feelings of care (affection and concern) for their well‐being and success. I reflect on how these feelings structured my engagement with the work and my role as researcher and the practices of care that I developed for others and myself in order to cope. Departing from the notion that feelings are a natural and important part of doing fieldwork, I ask how we, as situated actors, deal with feelings of affection and concern. How do we cope with the physical and emotional demands of caring while doing our job? And what kinds of roles and strategies should we develop to protect others, ourselves and our research?
Cross‐cultural consumer acceptability of cooked aromatic (cv. Heukhyangchal) and non‐aromatic (cv. Sinnongheukchal) black rice with different milling degrees
Authors: Choi Sehun , Kim Inhwan , Seo Han‐Seok , Lee Jihyun
Published: July 2020

This study aimed to compare acceptances between consumers in the United States (n = 101) and Korea (n = 105) with respect to black rice samples varying in (a) cultivar, aromatic (cv. Heukhayngchal) versus non‐aromatic (cv. Sinnongheukchal), and (b) degree of milling (milled vs. un‐milled). Consumer acceptances of cooked black‐rice samples were also compared with those of cooked white (i.e., non‐colored) rice (cv. Dongjinchal). U.S. consumers were found to like cooked white rice more than black rice. Interestingly, U.S. consumers liked cooked milled black‐rice samples, regardless of their cultivars, while Korean consumers liked cooked un‐milled non‐aromatic black rice and cooked milled white rice. Penalty analysis and standard stepwise multivariate regression analysis revealed that textural and flavor attributes influenced the overall liking of cooked black‐rice samples, although their impacts were different between the two cultural backgrounds. In conclusion, this study shows that consumer acceptance of cooked black‐rice samples differs as a function of cultivar, milling degree, and consumer's cultural background.

Practical applications

Black rice is becoming more popular around the world because of its unique flavor and high nutrient content. This study provides better understanding about the impact of cultivar, milling degree, and consumer's cultural background on acceptability of cooked black rice for Korean and U.S. markets.
Revisiting the coupling of fatty acid to phospholipid synthesis in bacteria with FapR regulation
Authors: Machinandiarena Federico , Nakamatsu Leandro , Schujman Gustavo E. , de Mendoza Diego , Albanesi Daniela
Published: July 2020

A key aspect in membrane biogenesis is the coordination of fatty acid to phospholipid synthesis rates. In most bacteria, PlsX is the first enzyme of the phosphatidic acid synthesis pathway, the common precursor of all phospholipids. Previously, we proposed that PlsX is a key regulatory point that synchronizes the fatty acid synthase II with phospholipid synthesis in Bacillus subtilis. However, understanding the basis of such coordination mechanism remained a challenge in Gram‐positive bacteria. Here, we show that the inhibition of fatty acid and phospholipid synthesis caused by PlsX depletion leads to the accumulation of long‐chain acyl‐ACPs, the end products of the fatty acid synthase II. Hydrolysis of the acyl‐ACP pool by heterologous expression of a cytosolic thioesterase relieves the inhibition of fatty acid synthesis, indicating that acyl‐ACPs are feedback inhibitors of this metabolic route. Unexpectedly, inactivation of PlsX triggers a large increase of malonyl‐CoA leading to induction of the fap regulon. This finding discards the hypothesis, proposed for B. subtilis and extended to other Gram‐positive bacteria, that acyl‐ACPs are feedback inhibitors of the acetyl‐CoA carboxylase. Finally, we propose that the continuous production of malonyl‐CoA during phospholipid synthesis inhibition provides an additional mechanism for fine‐tuning the coupling between phospholipid and fatty acid production in bacteria with FapR regulation.
Screening soybean cyst nematode effectors for their ability to suppress plant immunity
Authors: Pogorelko Gennady , Wang Jianying , Juvale Parijat S. , Mitchum Melissa G. , Baum Thomas J.
Published: July 2020

The soybean cyst nematode (SCN), Heterodera glycines, is one of the most destructive pathogens of soybeans. SCN is an obligate and sedentary parasite that transforms host plant root cells into an elaborate permanent feeding site, a syncytium. Formation and maintenance of a viable syncytium is an absolute requirement for nematode growth and reproduction. In turn, sensing pathogen attack, plants activate defence responses and may trigger programmed cell death at the sites of infection. For successful parasitism, H. glycines must suppress these host defence responses to establish and maintain viable syncytia. Similar to other pathogens, H. glycines engages in these molecular interactions with its host via effector proteins. The goal of this study was to conduct a comprehensive screen to identify H. glycines effectors that interfere with plant immune responses. We used Nicotiana benthamiana plants infected by Pseudomonas syringae and Pseudomonas fluorescens strains. Using these pathosystems, we screened 51 H. glycines effectors to identify candidates that could inhibit effector‐triggered immunity (ETI) and/or pathogen‐associated molecular pattern (PAMP)‐triggered immunity (PTI). We identified three effectors as ETI suppressors and seven effectors as PTI suppressors. We also assessed expression modulation of plant immune marker genes as a function of these suppressors.
P‐Hacking, P‐Curves, and the PSM–Performance Relationship: Is There Evidential Value?
Authors: Vogel Dominik , Homberg Fabian
Published: July 2020

Recent developments in the social sciences have demonstrated that we cannot uncritically aggregate the published research on a particular effect to conclude about its presence or absence. Instead, questionable research practices such as p‐hacking (conducting additional analyses or collecting new data to obtain significant results) and selective publication of significant results can produce a body of published research that misleads readers even if it contains many significant results. It is, therefore, necessary to assess the evidential value of the research on a certain effect; that is, one must rule out that it is the result of questionable research practices. We introduce the p‐curve method to public administration research and apply it to the research on the relationship between public service motivation (PSM) and individual performance, to demonstrate how the evidential value of a body of published research can be assessed. We find that this particular literature contains evidential value.
High velocity impact of an Fe/Cr/Mn/Ni high entropy alloy
Authors: Hawkins M. Cameron , Thomas Sarah , Hixson Robert , Li Nan , Fensin Saryu
Published: July 2020

A series of shock loading experiments were conducted on High Entropy Alloy (HEA) samples consisting of Fe/Cr/Mn/Ni in weight percentages of 25.2/23.5/24.8/26.5. Characterizing this transition metal alloy is a first step in understanding the shock compression response of this relatively new class of alloy. A single stage light gas gun was used to conduct a series of flyer plate symmetric impact experiments to obtain fundamental dynamic properties. Photonic Doppler Velocimetry (PDV) diagnostics were employed to measure the free surface velocity on the back of each target during dynamic compression. These experiments yielded four data points that are in reasonable agreement with an estimated Hugoniot for the material.
Four-View Split-Image Fragment Tracking in Hypervelocity Impact Experiments
Authors: Watson Erkai , Kunert Nico , Putzar Robin , Maas Hans-Gerd , Hiermaier Stefan
Published: July 2020

Hypervelocity impacts (HVI) often cause significant fragmentation to occur in both target and projectile materials, and is often encountered in space debris and planetary impact applications [1]–[5]. In this paper, we focus on determining the individual velocities and sizes of fragments tracked in high-speed images. Inspired by velocimetry methods such as Particle Image Velocimetry (PIV) [6] and Particle Tracking Velocimetry (PTV) [7] and building on past work [8], we describe the setup and algorithm used for measuring fragmentation data.
Statistical Distributions of the Elastic Moduli of Particle Aggregates at the Mesoscale
Authors: Pekmezi Gerald , Littlefield David , Chareyre Bruno
Published: July 2020

The current work is part of an ongoing effort to couple the Discrete Element Method (DEM), used as a mesoscale method, with Statistical Mechanics in order to construct a framework for the modeling, homogenization, and uncertainty quantification of particulate geomaterials. The aspect of the framework tackled in this work, is the quantification of stress and deformation of heterogenous DE models. Such quantification is necessary to allow DEM to “speak continuum”. DEM is a discrete particle method, wherein the concept of “stress” does not fit naturally, but where each particle pair is considered to interact through discrete forces. Additionally, DEM is an explicit method, and equivalent continuum deformation must be defined in the context of particle kinematics.
Assessment and Validation of Collision “Consequence” Method of Assessing Orbital Regime Risk Posed by Potential Satellite Conjunctions
Authors: Lechtenberg Travis F. , Hejduk Matthew D.
Published: July 2020

Collision risk management theory requires a thorough assessment of both the likelihood and consequence of potential collision events. Satellite conjunction risk assessment has produced a highly-developed theory for assessing the likelihood of collision but typically neglects to account for the consequences of a given collision. While any collision may compromise the operational survival of a space-craft, the amount of debris produced by the potential collision, and therefore the degree to which the orbital corridor may be compromised, can vary greatly among satellite conjunctions. Previous studies leveraged work on satellite collision modeling to develop a method to estimate whether a particular collision is likely to produce a relatively large or relatively small amount of resultant debris. The approximation of the number of debris pieces is dependent on a mass estimation process for the secondary objects utilizing the radar cross section of said object. This study examines the validity of the mass estimation process and establishes uncertainty bounds on the secondary object mass which will be used to best approximate the possible consequences of a prospective collision.
Updates to the DebriSat Project in Support of Improving Breakup Models and Orbital Debris Risk Assessments
Authors: Cowardin Heather , Anz-Meador Phillip , Murray James , Liou J.-C. , Christiansen Eric , Sorge Marlon , Fitz-Coy Norman , Huynh Tom
Published: July 2020

Existing DOD and NASA satellite breakup models are based on a key laboratory test, the 1992 Satellite Orbital debris Characterization Impact Test (SOCIT), which has supported many applications and matched on-orbit events involving older satellite designs reasonably well over the years. To update and improve these models, the NASA Orbital Debris Program Office, in collaboration with the Air Force Space and Missile Systems Center, The Aerospace Corporation, and the University of Florida, conducted a hypervelocity impact test using a high-fidelity mock-up satellite, DebriSat, in controlled and instrumented laboratory conditions. DebriSat is representative of present-day LEO satellites, having been constructed with modern spacecraft materials and techniques. The DebriSat fragment ensemble provided a variety of shapes, bulk densities, and dimensions. Fragments down to 2 mm in size are being characterized by their physical and derived properties. A subset of fragments will be analyzed further in laboratory radar and optical facilities to update the existing radar-based NASA Size Estimation Model (SEM) and develop a comparable optical-based SEM. Thoroughly understanding size estimates from ground-based optical and radar sensors is one of the key parameters used in assessing the environment and the risks that debris present to operational spacecraft. The data will inform updates to the current NASA Standard Satellite Breakup Model (SSBM);, which was formulated using laboratory and ground-based measurements of on-orbit fragmentation events to describe an average breakup for spacecraft and upper stage collisions and explosions. DebriSat will extend the laboratory data ensemble. The DebriSat shape and density categories provide a baseline for non-spherical projectile hypervelocity impact testing for damage assessment. The data from these tests, simulations, and analyses will be used to update the NASA Orbital Debris Engineering Model (ORDEM) with more realistic simulations of catastrophic fragmentation events for modern satellites and to assess the risk posed by the orbital debris environment. This paper provides an overview of the project, updates on the characterization process, and the NASA analysis status.
3D Printed Conical Shaped Charge Performance
Authors: Mulligan Phillip , Johnson Catherine , Ho Jason , Lough Cody , Kinzel Edward
Published: July 2020

A Conical Shaped Charge (CSC) is a versatile device utilized in construction, mining, petroleum and defense industries. The geometry and material structure of the metal liner play an integral role in the CSC performance. The performance of CSC liners has been relatively well-characterized for liners manufactured via hydroforming, hydraulic pressing, or turning on a CNC lathe. With advancements in Additive Manufacturing (AM) CSC liners can be 3D printed with metal powders. AM can provide significant design freedom in terms of realizing better properties through introduced hierarchic structuring or anisotropy. However, it is unclear as to how metal liners produced with Selective Laser Melting (SLM), will influence the conical shaped charge’s performance. This paper explores the performance, relative to the penetration of steel plates, of CSCs using 3D printed metal liners benchmarked against machined liners. The metal liners were printed with SLM parameters that were optimized to maximize the print density. The metal liner dimensions (thickness, height, and outer diameter) were designed using the recommended ratios of the liner’s inner diameter presented by Virgil (1988). The 3D printed metal liners are compared to a CNC machined liner, with the same dimensions. The comparison enables the evaluation of how 3D printing a liner influences penetration performance. The results indicate conical shaped charges could utilize 3D printed liners. These results open a wide range of performance design opportunities that cannot be achieved via conventional manufacturing and justify the current increased cost associated with additive manufacturing metal components. Future work will continue to explore how print density, printed material, and advanced geometries modify the conical shaped charge performance.
A Predictive Non-Dimensional Scaling Law for the Plate Perforation of Several Aluminum Alloys by Fragment-Simulating Projectiles
Authors: Chen Weinong , Guo Zherui
Published: July 2020

An equation was previously-presented to predict the ballistic-limit velocity for the perforation of aluminum armor plates by fragment-simulating projectiles (FSP). The ballistic-limit equation was presented in terms of dimensionless parameters so that the geometric and material problem scales are identified. Previously published predictions and data for two different FSP projectile calibers (12.7 mm and 20 mm) and two different strength aluminum alloys show the scaling law to be accurate. In this paper we extend the same concept to several other alloys and show that this scaling law is predictive.
Coils, Codes and Comets: My Attempts to Partially Understand Some Particular Aspects of Hypervelocity Impacts
Authors: Crawford David A.
Published: July 2020

At the time of this writing in 2019, I have been studying hypervelocity impacts for about 34 years. I attended my first Hypervelocity Impact Symposium in 1992. In this paper, I attempt to show what I’ve been up to all this time but also show some of the things I’ve learned along the way. I’ve singled out three topics that stand out in my mind as milestones in my career: the impact of Comet Shoemaker-Levy 9 on Jupiter in 1994, the development of adaptive mesh refinement for the CTH hydrocode in 1998-2001 and my ongoing studies of hypervelocity impact-generated magnetic fields from 1985 to the present day.
Lactoferrin-Derived Peptide Lactofungin Is Potently Synergistic with Amphotericin B
Authors: Fernandes Kenya E. , Payne Richard J. , Carter Dee A.
Published: July 2020

Lactoferrin (LF) is an iron-binding glycoprotein with broad-spectrum antimicrobial activity. Previously, we discovered that LF synergistically enhanced the antifungal efficacy of amphotericin B (AMB) across a variety of yeast species and subsequently hypothesized that this synergy was enhanced by the presence of small peptides derived from the whole LF molecule. In this study, LF was digested with pepsin under a range of conditions. The resulting hydrolysates exhibited enhanced synergy with AMB compared to its synergy with undigested LF.
Intratracheal Inoculation with Brucella melitensis in the Pregnant Guinea Pig Is an Improved Model for Reproductive Pathogenesis and Vaccine Studies
Authors: Hensel Martha E. , Chaki Sankar P. , Stranahan Lauren , Gregory Anthony E. , van Schaik Erin J. , Garcia-Gonzalez Daniel G. , Khalaf Omar , Samuel James E. , Arenas-Gamboa Angela M.
Published: July 2020

Reproductive failure is the hallmark of brucellosis in animals. An uncommon but important complication in pregnant women who become acutely infected withBrucella melitensisis spontaneous pregnancy loss or vertical transmission to the fetus. Unfortunately, the mechanism behind reproductive failure is still obscure, partially due to the lack of a proper study model. Recently, it was demonstrated that intratracheal (IT) inoculation of nonpregnant guinea pigs would replicate features of clinical disease in humans.
Third Helical Domain of the Nipah Virus Fusion Glycoprotein Modulates both Early and Late Steps in the Membrane Fusion Cascade
Authors: Zamora J. Lizbeth Reyes , Ortega Victoria , Johnston Gunner P. , Li Jenny , André Nicole M. , Monreal I. Abrrey , Contreras Erik M. , Whittaker Gary R. , Aguilar Hector C.
Published: July 2020

The
Paramyxoviridae
family includes important human and animal pathogens, such as measles, mumps, and parainfluenza viruses and the deadly henipaviruses Nipah (NiV) and Hendra (HeV) viruses. Paramyxoviruses infect the respiratory tract and the central nervous system (CNS) and can be highly infectious. Most paramyxoviruses have a limited host range. However, the biosafety level 4 NiV and HeV are highly pathogenic and have a wide mammalian host range. Nipah viral infections result in acute respiratory syndrome and severe encephalitis in humans, leading to 40 to 100% mortality rates. The lack of licensed vaccines or therapeutic approaches against NiV and other important paramyxoviruses underscores the need to understand viral entry mechanisms. In this study, we uncovered a novel role of a third helical region (HR3) of the NiV fusion glycoprotein in the membrane fusion process that leads to viral entry. This discovery sets HR3 as a new candidate target for antiviral strategies for NiV and likely for related viruses.
Supplemental Material: Age constraints on surface deformation recorded by fossil shorelines at Cape Range, Western Australia
Authors: Sandstrom Michael R , al. et
Published: July 2020

Figures S1–S8 and Tables S1–S5.
Supplemental Material: First-cycle sand supply and the evolution of the eastern Canadian continental margin: Insights from Pb isotopes in the Mesozoic Scotian Basin
Authors: Blowick Aoife , al. et
Published: July 2020

S1: Statistical Analysis of Pb isotopes in K-feldspar; S2: Pb isotopic compositions of K-feldspars; S3: Thorogenic Pb Plots.
Optimised retinopathy of prematurity screening guideline in China based on a 5-year cohort study
Authors: Yang Qian , Zhou Xiaohong , Ni Yingqin , Shan Haidong , Shi Wenjing , Yin Xuelei , Liu Jiangqin , Huang Xin
Published: July 2020

Purposes

To develop an optimised retinopathy of prematurity (ROP) screening guideline by adjusting the screening schedule and thresholds of gestational age (GA) and birth weight (BW).

Methods

A multicentre retrospective cohort study was conducted based on data from four tertiary neonatal intensive care units in Shanghai, China. The medical records of enrolled infants, born from 2012 to 2016 who underwent ROP examinations, were collected and analysed. The incidence and risk factors for ROP were analysed in all infants. Postnatal age (PNA) and postmenstrual age (PMA) of infants, detected to diagnose ROP for the first time, were compared with the present examination schedule. The predictive performance of screening models was evaluated by internally validating sensitivity and specificity.

Results

Of the 5606 eligible infants, ROP was diagnosed in 892 (15.9%) infants; 63 (1.1%) of them received treatment. The mean GA of ROP patients was 29.4±2.4 weeks, and the mean BW was 1260±330 g. Greater prematurity was associated with an older PNA at which ROP developed. The minimum PMA and PNA at which diagnosis of treatable ROP occurred were 32.43 and 3 weeks, respectively. The optimised criteria (GA <32 weeks or BW <1600 g) correctly predicted 98.4% type 1 ROP infants, reducing the infants requiring examinations by 43.2% when internally validated.

Conclusions

The incidence of type 1 ROP and the mean GA and BW of ROP infants have decreased in China. The suggested screening threshold and schedule may be reliably used to guide the modification of ROP screening guideline and decrease medical costs.
Physical distancing interventions and incidence of coronavirus disease 2019: natural experiment in 149 countries
Authors: Islam Nazrul , Sharp Stephen J , Chowell Gerardo , Shabnam Sharmin , Kawachi Ichiro , Lacey Ben , Massaro Joseph M , D’Agostino Ralph B , White Martin
Published: July 2020

Objective

To evaluate the association between physical distancing interventions and incidence of coronavirus disease 2019 (covid-19) globally.

Design

Natural experiment using interrupted time series analysis, with results synthesised using meta-analysis.

Setting

149 countries or regions, with data on daily reported cases of covid-19 from the European Centre for Disease Prevention and Control and data on the physical distancing policies from the Oxford covid-19 Government Response Tracker.

Participants

Individual countries or regions that implemented one of the five physical distancing interventions (closures of schools, workplaces, and public transport, restrictions on mass gatherings and public events, and restrictions on movement (lockdowns)) between 1 January and 30 May 2020.

Main outcome measure

Incidence rate ratios (IRRs) of covid-19 before and after implementation of physical distancing interventions, estimated using data to 30 May 2020 or 30 days post-intervention, whichever occurred first. IRRs were synthesised across countries using random effects meta-analysis.

Results

On average, implementation of any physical distancing intervention was associated with an overall reduction in covid-19 incidence of 13% (IRR 0.87, 95% confidence interval 0.85 to 0.89; n=149 countries). Closure of public transport was not associated with any additional reduction in covid-19 incidence when the other four physical distancing interventions were in place (pooled IRR with and without public transport closure was 0.85, 0.82 to 0.88; n=72, and 0.87, 0.84 to 0.91; n=32, respectively). Data from 11 countries also suggested similar overall effectiveness (pooled IRR 0.85, 0.81 to 0.89) when school closures, workplace closures, and restrictions on mass gatherings were in place. In terms of sequence of interventions, earlier implementation of lockdown was associated with a larger reduction in covid-19 incidence (pooled IRR 0.86, 0.84 to 0.89; n=105) compared with a delayed implementation of lockdown after other physical distancing interventions were in place (pooled IRR 0.90, 0.87 to 0.94; n=41).

Conclusions

Physical distancing interventions were associated with reductions in the incidence of covid-19 globally. No evidence was found of an additional effect of public transport closure when the other four physical distancing measures were in place. Earlier implementation of lockdown was associated with a larger reduction in the incidence of covid-19. These findings might support policy decisions as countries prepare to impose or lift physical distancing measures in current or future epidemic waves.
30-minute postload plasma glucose levels during an oral glucose tolerance test predict the risk of future type 2 diabetes: the Hisayama Study
Authors: Hirakawa Yoichiro , Hata Jun , Yoshinari Masahito , Higashioka Mayu , Yoshida Daigo , Shibata Mao , Honda Takanori , Sakata Satoko , Kato Hiroyuki , Teramoto Takanori , Maki Hideki , Nishimoto Shozo , Kitazono Takanari , Ninomiya Toshiharu
Published: July 2020

Introduction

To investigate the associations of 30 min postload plasma glucose (30 mPG) levels during an oral glucose tolerance test (OGTT) with the risk of future diabetes in a general Japanese population.

Research design and methods

A total of 2957 Japanese community-dwelling residents without diabetes, aged 40–79 years, participated in the examinations in 2007 and 2008 (participation rate, 77.1%). Among them, 2162 subjects who received 75 g OGTT in a fasting state with measurements of plasma glucose level at 0, 30, and 120 min were followed up for 7 years (2007–2014). Cox’s proportional hazards model was used to estimate HRs and their 95% CIs of each index for the development of type 2 diabetes using continuous variables and quartiles with adjustment for traditional risk factors. The influence of 30 mPG on the predictive ability was estimated with Harrell’s C-statistics, integrated discrimination improvement (IDI), and the continuous net reclassification index (cNRI).

Results

During follow-up, 275 subjects experienced type 2 diabetes. Elevated 30 mPG levels were significantly associated with increased risk of developing diabetes (p<0.01 for trend): the multivariable-adjusted HR was 8.41 (95% CI 4.97 to 14.24) for the highest versus the lowest quartile, and 2.26 (2.04 to 2.52) per 1 SD increase. This association was attenuated but remained significant after further adjustment for fasting and 2-hour postload plasma glucose levels. Incorporation of 30 mPG into the model including traditional risk factors with fasting and 2-hour postload plasma glucose levels for diabetes improved the predictive ability of type 2 diabetes (improvement in Harrell’s C-statistics values: from 0.828 to 0.839, p<0.01; IDI: 0.016, p<0.01; cNRI: 0.103, p=0.37).

Conclusions

Elevated 30 mPG levels were associated with increased risk of diabetes, and inclusion of 30 mPG levels significantly improved the predictive ability for future diabetes, suggesting that 30 mPG may be useful for identifying high-risk populations for type 2 diabetes.
Experimental Nonlinear Flutter Analysis of a Cantilever Wing/Store
Authors: Alizadeh A. , Ebrahimi Z. , Mazidi A. , Fazelzadeh S. Ahmad
Published: July 2020

This paper studies experimentally the nonlinear aeroelastic and flutter behavior of a cantilever plate wing with an external store. The wing model that is constructed from plexiglass sheet is designed and tested in a closed-circuit subsonic wind tunnel. To deal with the structural nonlinearities of the model, various analysis tools such as time history plots, phase-plane projections and Fast Fourier Transform (FFT) have been used for detecting the critical and post-critical behaviors of the structure. The results show that flutter takes place by the coupling between the torsional and bending modes. A good correlation between the present experiments and previous numerical results is obtained. The nonlinear aeroelastic response and flutter boundary are investigated for different sweep angles. The flutter velocity and amplitudes of limit cycle oscillations (LCOs) increase rapidly with increasing sweep angle. The nonlinear response of the wing with an external store is also investigated, with the effect of store location on the nonlinear flutter boundary evaluated.
Max-independent set and the quantum alternating operator ansatz
Authors: Saleem Zain Hamid
Published: July 2020

The maximum-independent set (MIS) problem of graph theory using the quantum alternating operator ansatz is studied. We perform simulations on the Rigetti Forest simulator for the square ring, [Formula: see text], and [Formula: see text] graphs and analyze the dependence of the algorithm on the depth of the circuit and initial states. The probability distribution of observation of the feasible states representing maximum-independent sets is observed to be asymmetric for the MIS problem, which is unlike the Max-Cut problem where the probability distribution of feasible states is symmetric. For asymmetric graphs, it is shown that the algorithm clearly favors the independent set with the larger number of elements even for finite circuit depth. We also compare the approximation ratios for the algorithm when we choose different initial states for the square ring graph and show that it is dependent on the choice of the initial state.
Image-Based Optical-Fiber Force Sensor for Minimally Invasive Surgery with ex-vivo Validation
Authors: Bandari Naghmeh , Dargahi Javad , Packirisamy Muthukumaran
Published: July 2020

During minimally invasive surgery, surgeons insert specially-designed instruments through a small incision into the patient’s body. Despite all the advantages of this procedure, surgeons do not have the natural force feedback in the surgery. Force feedback helps the surgeon to apply an appropriate force to avoid tissue damage. As a solution, this study was aimed at the ex-vivo validation of a proposed image-based optical force sensor with light intensity modulation principle. The sensor was to be integrated with conventional minimally invasive instruments and was working based on variable bending radius sensing principle. To this end, the sensor was integrated on the jaw of a custom-designed minimally invasive grasper and its performance was assessed ex-vivo. Furthermore, the light intensity measurement of this study was performed utilizing an image-based technique to avoid the complexities of using photodetectors. The sensor was calibrated using a rate-dependent learning-based support-vector-regression model, which showed an adjusted−R
2 of 94%. The results of the ex-vivo test on a freshly excised bovine muscle tissue showed fair agreement between sensor measurements and ground truth. Therefore, the proposed sensor was concluded as applicable for minimally invasive surgeries by comparing the minimum performance requirements of force sensors for surgical applications.
Miniaturized Water‐Jet Ultrasound Indentation System for Quantitative Assessment of Articular Cartilage Degeneration: A Validation Study
Authors: Huang Yan-Ping , Zheng Yong-Ping
Published: July 2020

Osteoarthritis is a common joint disease affecting a large population especially the elderly where cartilage degeneration is one of its hallmark symptoms. There is a need to develop new devices and instruments for the early detection and treatment of cartilage degeneration. In this study, we describe the development of a miniaturized water‐jet ultrasound indentation probe for this purpose. To evaluate the system, we applied it to characterize the degeneration of articular cartilage with the measurement of its morphologic, acoustic, and mechanical properties, using the enzymatic digestions of cartilage as a model of OA. Fifty cartilage samples were tested with 10 of them used for the reproducibility study and the other 40 for collagenase and trypsin digestions. Thickness, integrated reflection coefficient (IRC), effective stiffness, and energy dissipation ratio (EDR) were used to quantify the change of articular cartilage before and after degeneration. The measurement reproducibility as represented by the standardized coefficient of variation (SCV) was 2.6%, 10.2%, 11.5%, and 12.8% for thickness, IRC, stiffness, and EDR, respectively. A significant change of IRC, stiffness, and EDR was detected after degeneration by the designed probe (p < 0.05). There was also a significant difference of IRC, stiffness, and EDR between trypsin and collagenase digestions (p < 0.001). In conclusion, a miniaturized water‐jet ultrasound indentation probe has been designed, which has been successfully used to detect and differentiate cartilage degeneration simulated by enzymatic digestions. This probe, with future development, can be potentially suitable for quantitative assessment of cartilage degeneration with an arthroscopic operation.