bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling and analyzing rheological behavior of sour lemon juice concentrate using image processing methods
Authors: Çavdir Esra , Akben Selahaddin B. , Bozdoğan Adnan
Published: May 2020

In this study, temperature‐concentration related rheological behavior of sour lemon juice concentrate (SLJC) were investigated. Lemons were squeezed, and lemon juices were obtained. SLJC samples were produced by two methods: atmospheric and vacuum conditions. The rheological properties of SLJC at 10, 20, 30, 40, and 50°C for each 31, 36, 41, 46, 51 °Bx were measured with rheometer. Firstly, it was determined that the SLJC showed Newtonian flow behavior at measured concentrations and temperatures. Then, viscosity of SLJC produced under vacuum conditions was determined higher than SLJC produced under atmospheric conditions. This difference was calculated statistically significant (p < .05). Furthermore, activation energy values of samples produced under atmospheric and vacuum conditions ranged between 13.6–24.0 kJ/mol and 9.0–17.9 kJ/mol, respectively. Finally, temperature‐concentration dependent viscosity variations were modeled by surface equations, and the data predicted were transformed into images to provide visual analysis. It was determined by images that the viscosity change is proportional to concentration while inversely proportional to temperature. Ascorbic acid value was found higher under vacuum conditions than atmospheric conditions. In contrast, the HMF value was detected in low quantities under vacuum conditions.
In situ structure of the Caulobacter crescentus flagellar motor and visualization of binding of a CheY‐homolog
Authors: Rossmann Florian M. , Hug Isabelle , Sangermani Matteo , Jenal Urs , Beeby Morgan
Published: May 2020

Bacterial flagellar motility is controlled by the binding of CheY proteins to the cytoplasmic switch complex of the flagellar motor, resulting in changes in swimming speed or direction. Despite its importance for motor function, structural information about the interaction between effector proteins and the motor are scarce. To address this gap in knowledge, we used electron cryotomography and subtomogram averaging to visualize such interactions inside Caulobacter crescentus cells. In C. crescentus, several CheY homologs regulate motor function for different aspects of the bacterial lifestyle. We used subtomogram averaging to image binding of the CheY family protein CleD to the cytoplasmic Cring switch complex, the control center of the flagellar motor. This unambiguously confirmed the orientation of the motor switch protein FliM and the binding of a member of the CheY protein family to the outside rim of the C ring. We also uncovered previously unknown structural elaborations of the alphaproteobacterial flagellar motor, including two novel periplasmic ring structures, and the stator ring harboring eleven stator units, adding to our growing catalog of bacterial flagellar diversity.
Comparison of four commercially available chromogenic media to identify Candida albicans and other medically relevant Candida species
Authors: Scharmann Ulrike , Kirchhoff Lisa , Chapot Valerie le Saout , Dziobaka Jan , Verhasselt Hedda Luise , Stauf Raphael , Buer Jan , Steinmann Joerg , Rath Peter‐Michael
Published: May 2020

Background

The number of invasive Candida infections has significantly increased in recent decades. For the successful treatment of fungal infections, rapid identification at the species level, particularly in polyfungal infections, is a key factor.

In this study, four commercially available chromogenic media, CandiSelect™ 4 (CS4), chromID™ Candida Agar (CCA), BBL™ CHROMagar™ Candida Medium (BBL) and Brilliance™ Candida Agar (BCA) were evaluated for Candida identification.

Material/Methods

Overall, 181 bronchial secretion samples from intensive care patients were analysed prospectively. In addition, 18 primarily sterile materials, previously tested positive for Candida, were investigated retrospectively. All samples were cultured as recommended by the manufacturer and visually inspected after 24 and 48 hours by three independent investigators. As a control, colonies were identified by MALDI‐TOF MS. Specificity and sensitivity were determined for C albicans identification prospectively.

Results

CS4 and BCA showed the best overall consensus with the identification results reached by MALDI‐TOF MS for Candida albicans and species. A clear differentiation between the species could be ascertained via easily identifiable, species‐specific coloration in contrast to BBL and CCA. Sensitivity for C albicans (n = 73) identification varied between 32% (BCA) and 69% (CS4 and CCA) after 24 hours and 68% (BBL) and 82% (BCA) after 48 hours incubation, while specificity ranged between 62% (BBL) and 81% (CCA) after 24 hours and 82% (BBL) and 85% (CS4) after 48 hours.

Conclusion

CS4 and BCA are recommended for routine identification of Candida species in human samples.
Periodontitis in tonsil cancer patients—A comparative study in accordance with tumour p16 status
Authors: Keinänen Arvi , Marinescu‐Gava Magdalena , Uittamo Johanna , Hagström Jaana , Marttila Emilia , Snäll Johanna
Published: May 2020

Objectives

We assessed the periodontal situation radiologically according to tumour p16 status.

Materials and methods

Patients with a diagnosis of tonsillar cancer and availability of a digital panoramic radiograph (DPR) during a 5‐year period were included in this retrospective study. The predictor variables were periodontal stability, marginal bone loss, marginal bone loss without periodontal stability and total number of teeth. Periodontal status was compared with p16 status, age, gender, smoking and alcohol use.

Results

Among 115 patients included in the analyses (p16‐negative, n = 24; p16‐positive, n = 91), smoking (p < .0001), heavy alcohol use (p < .0001) and total number of teeth (p = .0001) were significantly associated with p16 status. Current smoking (OR = 7.3) and heavy alcohol use (OR = 10.1) increased the risk of p16‐negative cancer.

Conclusions

Patients with p16‐negative tonsillar carcinoma had less teeth than patients with p16‐positive tumours. Other periodontal findings were common in both groups without statistical significance. Heavy alcohol use and smoking were the most important risk factors for p16‐negative tonsillar carcinoma.
C4 grasses adapted to low precipitation habitats show traits related to greater mesophyll conductance and lower leaf hydraulic conductance
Authors: Pathare Varsha S. , Sonawane Balasaheb V. , Koteyeva Nouria , Cousins Asaph B.
Published: May 2020

In habitats with low water availability, a fundamental challenge for plants will be to maximize photosynthetic C‐gain while minimizing transpirational water‐loss. This trade‐off between C‐gain and water‐loss can in part be achieved through the coordination of leaf‐level photosynthetic and hydraulic traits. To test the relationship of photosynthetic C‐gain and transpirational water‐loss, we grew, under common growth conditions, 18 C4 grasses adapted to habitats with different mean annual precipitation (MAP) and measured leaf‐level structural and anatomical traits associated with mesophyll conductance (gm) and leaf hydraulic conductance (Kleaf). The C4 grasses adapted to lower MAP showed greater mesophyll surface area exposed to intercellular air spaces (Smes) and adaxial stomatal density (SDada) which supported greater gm. These grasses also showed greater leaf thickness and vein‐to‐epidermis distance, which may lead to lower Kleaf. Additionally, grasses with greater gm and lower Kleaf also showed greater photosynthetic rates (Anet) and leaf‐level water‐use efficiency (WUE). In summary, we identify a suite of leaf‐level traits that appear important for adaptation of C4 grasses to habitats with low MAP and may be useful to identify C4 species showing greater Anet and WUE in drier conditions.
Retail Deliveries by Drones: How Will Logistics Networks Change?
Authors: Perera Sandun , Dawande Milind , Janakiraman Ganesh , Mookerjee Vijay
Published: May 2020

Emerging technologies such as drone delivery services enable retailers to cost‐effectively offer unprecedented delivery speed and adaptable delivery lead times using dedicated aerial vehicles for individual orders. A natural and important question arises: What is the impact of a drone delivery system (DDS) on a retailer’s extant logistics parameters, for example, the number of customer‐facing delivery centers (last‐mile warehouses) it uses and delivery lead times it offers? On the one hand, the ability to reach customers faster than through traditional means argues for more centralization of delivery services. On the other hand, more decentralization can allow the retailer to offer hitherto unheard‐of delivery lead times and thereby spur demand. We show that, as drone technology matures and becomes more cost‐effective, delivery networks will become increasingly decentralized while delivering products at faster speeds. While perfect delivery customization—under which each demand location is offered a customized delivery guarantee—is theoretically feasible under a DDS, it may not be practical to implement such a finely differentiated delivery strategy. Instead, we show that retailers can recover a significant portion of the profit under this ideal scenario by offering limited delivery‐time customization, that is, partitioning the market into a few delivery “zones” and offering the best feasible delivery guarantee for each zone. In physically congested metropolitan markets, where retailers may be forced to operate with only a few delivery centers, it may be optimal to operate a DDS by offering delivery guarantees that are inferior to the best possible in order to throttle unprofitable demand. In such markets, the effectiveness of limited delivery‐time customization increases as the extent of physical congestion increases.
Sleep quality features and their association with mood symptoms and cognitive factors in a non‐clinical sample of older Brazilian adults
Authors: da Silva Rosiêne V. , Soares Nayron M. , Pereira Gabriela M. , da Silva Júnior Edivan G. , do Carmo Eulálio Maria
Published: May 2020

Aim

There is strong interest in sleep disorders in the elderly, but there are gaps in identifying how multiple factors affect sleep quality in this population. We aimed to assess sleep quality and its relationship to mood, general cognition, and sociodemographic factors in a sample of cognitively active older adults.

Methods

We assessed 105 non‐clinical older adults (mean age ± SD: 69.64 ± 0.66 years) based on a sociodemographic profile questionnaire, the Beck Anxiety Inventory, the Beck Depression Inventory II, the Montreal Cognitive Assessment, the Pittsburgh Sleep Quality Index, and the Epworth Sleepiness Scale. Separate analyses were conducted, controlled by sleep quality and daytime sleepiness, to understand how variables were associated.

Results

About 46.7% of individuals had significantly poor sleep quality. Univariate analysis showed that non‐workers had a lower risk of impaired sleep quality (prevalence ratio (PR) = 0.67; P = 0.044). However, there was an increased risk of poor sleep quality in those experiencing depressive symptoms (PR = 1.78; P < 0.001) and anxiety symptoms (PR = 1.98; P < 0.001). In multivariate analysis, the language component of the Montreal Cognitive Assessment (PR = 0.80; P = 0.011) was associated with a lower risk of poor sleep quality, and anxiety symptoms (PR = 1.99; P < 0.001) remained significantly associated with a higher risk of poor sleep quality. No significant difference was observed in variables related to daytime sleepiness.

Conclusion

We found that overall quality of sleep potentially relates to mood, cognition, and sociodemographic factors. Further studies using multifactorial approaches to sleep investigation are required.
Expression of iron regulatory proteins in full‐term swine placenta
Authors: Rajamanickam Kandasamy , Leela Venkatasubramanian , Suganya Gopalakrishnan , Basha Sabiha Hayath , Parthiban Manoharan , Pazhanivel Natesan , Mangala Gowri Angappan
Published: May 2020

In swine, even though the pregnant sows were with iron abundance, the inborn iron reserve of piglets was compromised. This indicates the insufficiency of molecular machinery involved in local placental iron flux. Here, we investigated the expression of iron regulatory proteins like hepcidin and ferroportin and also their association with iron reserve, inflammation and oxidative stress in placenta of full‐term pregnant sows (n = 6). Amplification and sequencing of placental DNA confirmed the presence of hepcidin (MN579557) and ferroportin (MN565887) sequences and their 100% identity with existing GenBank data. Real‐time amplification of placental mRNA revealed significant higher expression of hepcidin (p < .05) than ferroportin. Western blot analysis of placental tissues revealed specific bands for both hepcidin (~8 kDa) and ferroportin (~62 kDa) molecules. Immunohistochemistry revealed the immunoreactivity for both proteins in the cytoplasm and membrane of trophoblastic cells of the placenta. Hepcidin and ferroportin expressions were positively associated with placental non‐haem iron reserve (p < .0001; p = .033), lipid peroxidation (p = .0060; p < .0001) and reactive oxygen species level (p = .0092; p = .0292). Hepcidin expression was positively associated with interleukin – 6 (p = .0002) and interferon gamma (p < .0001) expressions but ferroportin expression was negatively associated with interleukin‐6 (p = .0005), interleukin‐1β (p = .0226) and interferon gamma (p = .0059) expressions. This indicates hepcidin and ferroportin may have a role in controlling the local placental iron flux by acting as a molecular bridge between iron trafficking and inflammation.
Bird response to hydrologic restoration of montane riparian meadows
Authors: Campos Brent R. , Burnett Ryan D. , Loffland Helen L. , Siegel Rodney B.
Published: May 2020

Montane riparian meadows foster biodiversity and support critical ecosystem services. A history of exploitation has left most riparian meadows throughout the Mountain West of the United States with incised channels, severely compromising their functionality. Hydrologic restoration of riparian meadows aims to increase overbank flow during spring run‐off and elevate groundwater levels in the dry season. Outcome‐based evaluations of the dominant meadow restoration methods are lacking and needed to ensure objectives are being met and to guide modifications where needed. We completed 1,282 point count surveys from 2009 to 2017 at 173 sampling locations across 31 montane riparian meadows in California restored using partial channel fill techniques (e.g. pond‐and‐plug) to evaluate the expected outcome of increased abundance of meadow birds. We analyzed trends in abundance for 12 focal bird species from 1 to 18 years after hydrologic restoration, substituting space for time in our mixed effects Poisson regression models that included covariates for the amount of riparian deciduous vegetation (RDV) before restoration, stream flow, precipitation, and temperature. We found evidence for a positive effect of time since restoration on abundance for 6 of the 12 species. Although pre‐restoration RDV cover was the most frequently supported predictor of abundance, high pre‐restoration cover of RDV slowed response rates for only two species, suggesting other elements of hydrologic function are also important for meadow birds. Drawing on our results, we provide suggestions for enhancing hydrologic restoration efforts in riparian meadows so that benefits may accrue more quickly to more bird species.
Which firms leave multi‐stakeholder initiatives? An analysis of delistings from the United Nations Global Compact
Authors: Rasche Andreas , Gwozdz Wencke , Lund Larsen Mathias , Moon Jeremy
Published: May 2020

This study analyzes which firms leave multi‐stakeholder initiatives (MSIs) for corporate social responsibility. Based on an analysis of all active and delisted business participants from the United Nations Global Compact between 2000 and 2015 (n = 15,853), we find that small and medium‐sized enterprises are more likely to leave than larger and publicly traded firms; that early adopters are less likely to leave than late adopters; and that the presence of a local network in a country reduces the likelihood of leaving. Based on these findings, we discuss theoretical implications related to MSIs' output legitimacy, the nature of organizational platforms supporting norm entrepreneurs within MSIs, and the occurrence of legitimacy spillover effects in local networks.
Encoding States Is Not Enough: The Case of Spanish Deadjectival Nominalizations1
Authors: Zato Zoltan
Published: May 2020

In this paper, I argue that mass deadjectival nominalizations likebelleza‘beauty’ encodeimperfectivestates, which explains why they are compatible with temporal modifiers, but not with aspectual ones. In contrast to what is claimed in Fábregas & Marín (2012), this paper provides empirical evidence that Spanish nominalizations can encode not only information related to lexical aspect (i.e. (a)telicity), but also information related to viewpoint aspect (i.e. (im)perfectivity). My analysis is based on Anderson's & Morzycki's (2015) model on gradability, in which gradable adjectives express states and degrees are derived from state‐kinds, which allows accounting for the properties of mass deadjectival nominalizations compositionally, insofar as they inherit the adjectival properties.
A phylogenomic tree inferred with an inexpensive PCR‐generated probe kit resolves higher‐level relationships among Neptis butterflies (Nymphalidae: Limenitidinae)
Authors: Ma Lijun , Zhang Yuan , Lohman David J. , Wahlberg Niklas , Ma Fangzhou , Nylin Soren , Janz Niklas , Yago Masaya , Aduse‐Poku Kwaku , Peggie Djunijanti , Wang Min , Zhang Peng , Wang Houshuai
Published: May 2020

Recent advances in obtaining reduced representation libraries for next‐generation sequencing permit phylogenomic analysis of species‐rich, recently diverged taxa. In this study, we performed sequence capture with homemade PCR‐generated probes to study diversification among closely related species in a large insect genus to examine the utility of this method. We reconstructed the phylogeny of Neptis Fabricius, a large and poorly studied nymphalid butterfly genus distributed throughout the Old World. We inferred relationships among 108 Neptis samples using 89 loci totaling up to 84 519 bp per specimen. Our taxon sample focused on Palearctic, Oriental and Australasian species, but included 8 African species and outgroups from 5 related genera. Maximum likelihood and Bayesian analyses yielded identical trees with full support for almost all nodes. We confirmed that Neptis is not monophyletic because Lasippa heliodore (Fabricius) and Phaedyma amphion (Linnaeus) are nested within the genus, and we redefine species groups for Neptis found outside of Africa. The statistical support of our results demonstrates that the probe set we employed is useful for inferring phylogenetic relationships among Neptis species and likely has great value for intrageneric phylogenetic reconstruction of Lepidoptera. Based on our results, we revise the following two taxa: Neptis heliodore comb. rev. and Neptis amphion comb. rev.
Successful recovery from severe COVID‐19 pneumonia after kidney transplantation: The interplay between immunosuppression and novel therapy including tocilizumab
Authors: Lauterio Andrea , Valsecchi Mila , Santambrogio Sara , De Carlis Riccardo , Merli Marco , Calini Angelo , Centonze Leonardo , Buscemi Vincenzo , Bottiroli Maurizio , Puoti Massimo , Fumagalli Roberto , De Carlis Luciano
Published: May 2020

Although immunosuppressed patients may be more prone to SARS‐CoV‐2 infection with atypical presentation, long‐term immunosuppression therapy may provide some sort of protection for severe clinical complications of COVID‐19. The interaction between immunosuppression and new antiviral drugs in the treatment of transplanted patients contracting COVID‐19 has not yet been fully investigated. Moreover, data regarding the optimal management of these patients are still very limited. We report a case of the successful recovery from severe COVID‐19 of a kidney‐transplanted patient treated with hydroxychloroquine, lopinavir/ritonavir, steroid, and tocilizumab.
Broader adaptive range of sympathetic burst size in response to blood pressure change in older women with greater arterial stiffness
Authors: Okada Yoshiyuki , Galbreath M. Melyn , Jarvis Sara S. , Shibata Shigeki , Vongpatanasin Wanpen , Levine Benjamin D. , Fu Qi
Published: May 2020

Key points

In this study, we focused on muscle sympathetic nerve activity (MSNA) burst size and occurrence separately as subcomponents of the sympathetic baroreflex in older adults, and we found that the distribution (variation) of burst size against burst occurrence was greater in women than men.

Older women had greater carotid artery stiffness compared with older men, while blood pressure (BP) distribution (variation) was comparable between sexes.

Sympathetic baroreflex sensitivity assessed with burst incidence was less sensitive as the carotid artery became stiffer in older men and women, while that assessed with burst area was more sensitive as the carotid artery became stiffer in older women but not in older men.

These results help us understand the mechanisms underlying the compensation for the impaired response of MSNA burst occurrence in older women with greater carotid artery stiffness to regulate BP similar to that in older men.

There are sex differences in arterial stiffness and neural control of blood pressure (BP) among older adults. We examined whether the sympathetic response to BP is greater in older women than men in burst size but not burst occurrence. Burst occurrence and size were assessed with burst interval and area of muscle sympathetic nerve activity, respectively, and the distributions of these indices were evaluated by range during supine rest in 61 healthy older subjects (30 men (69 ± 6 years) and 31 women (68 ± 6 years); means ± SD). Also, we analysed sympathetic baroreflex sensitivity (BRS) with burst occurrence and area simultaneously. Carotid β‐stiffness was measured with B‐mode ultrasonic image and carotid BP. The range of burst interval was smaller in older women than men (P = 0.002), while there was no difference in the range of burst area. Carotid β‐stiffness was greater in older women than men (6.7 ± 2.7 vs. 5.1 ± 2.7, P = 0.027). Sympathetic BRS assessed with burst incidence was lower in older women than men (‐2.3 ± 1.4 vs. ‐3.3 ± 1.4 bursts·100 beats‐1 mmHg‐1, P = 0.007), while this sex difference was observed when assessed with burst area after adjusting for carotid β‐stiffness (‐116.1 ± 135.0 vs. ‐185.9 ± 148.2 a.u. burst‐1 mmHg‐1, P = 0.040), but not before. Sympathetic BRS assessed with burst area was negatively (more sensitive) correlated with carotid β‐stiffness in older women (r = ‐0.53, P = 0.002) but not men. These data suggest that the response of burst size within each burst is augmented for the baroreflex BP control despite the impaired response of burst occurrence in older women with greater carotid stiffness.
Sadocepheus nortonroyi sp. nov. (Acari, Oribatida, Cepheidae) from Chile, with identification key to known species of the genus

Authors: Ermilov Sergey G.
Published: May 2020

A new species of oribatid mites of the family Cepheidae is described based on adults from rainforest in Chile. Sadocepheus nortonroyi sp. nov. differs from Sadocepheus foveolatus by the larger body size, the presence of transverse notogastral ridge and divergent lamellar cusps, and the location of notogastral setae on the notogastral surface. Explanations on placement of some species in Sadocepheus are presented. An identification key to known species of Sadocepheus is given.
Antibiofilm Activity of Lactobacillus plantarum 12 Exopolysaccharides against Shigella flexneri
Authors: Song Yinglong , Sun Mengying , Feng Lu , Liang Xue , Song Xing , Mu Guangqing , Tuo Yanfeng , Jiang Shujuan , Qian Fang
Published: May 2020

S. flexneri
is a widespread foodborne pathogen causing food contamination and responsible for food poisoning outbreaks related to various foods in developing countries. Not only has biofilm formation by
S. flexneri
been difficult to eliminate, but it has also increased the drug resistance of the strain. In the present study, it was demonstrated that L-EPSs secreted by
Lactobacillus plantrum
12 could inhibit
S. flexneri
biofilm formation on, adhesion to, and invasion into HT-29 cells. Also, L-EPSs could decrease the minimum biofilm elimination concentration (MBEC) of the antibiotics used against
S. flexneri
biofilm. Therefore, L-EPSs were shown to be bioactive macromolecules with the potential ability to act against
S. flexneri
infections.
Environmental Surveillance Complements Case-Based Surveillance of Acute Flaccid Paralysis in Polio Endgame Strategy 2019–2023
Authors: Chen Peng , Liu Yao , Wang Haiyan , Liu Guifang , Lin Xiaojuan , Zhang Weiyan , Ji Feng , Xu Qing , Tao Zexin , Xu Aiqiang
Published: May 2020

Interrupting wild poliovirus transmission and stopping circulating vaccine-derived poliovirus (cVDPV) outbreaks have been proposed as two global goals by the World Health Organization in the Global Polio Eradication Initiative (GPEI). This analysis, based on the 28-year acute flaccid paralysis (AFP) surveillance and 8-year environmental surveillance, provides continued high-quality surveillance performance in achieving the GPEI and detecting the circulation of enterovirus. Given the ongoing cVDPV outbreaks in the world, we present the surveillance capacity of environmental surveillance in capturing enterovirus circulation. The final poliovirus (especially VDPV) elimination has become increasingly complex, and the case-based AFP surveillance alone will lead to difficulties in early detecting dynamics of poliovirus transmission and monitoring the extent of environmental circulation. This study goes beyond previous work to provide a detailed comprehensive evaluation of the enterovirus surveillance and can be used to formulate a set of implementation plan and performance indicators for environmental surveillance.
Conidial Melanin of the Human-Pathogenic Fungus Aspergillus fumigatus Disrupts Cell Autonomous Defenses in Amoebae
Authors: Ferling Iuliia , Dunn Joe Dan , Ferling Alexander , Soldati Thierry , Hillmann Falk
Published: May 2020

Infections with
Aspergillus fumigatus
are usually acquired by an inhalation of spores from environmental sources. How spores of a saprophytic fungus have acquired abilities to withstand and escape the phagocytic attacks of innate immune cells is not understood. The fungal surface pigment dihydroxynaphtalene-melanin has been shown to be a crucial factor for the delay in phagosome maturation. Here, we show that this pigment also has a protective function against environmental phagocytes. Pigmented conidia escaped uptake and killing by the fungus-eating amoeba
Protostelium aurantium
. When ingested by the nonfungivorous phagocyte
Dictyostelium discoideum
, the pigment attenuated the launch of cell autonomous defenses against the fungal invader, such as membrane repair and autophagy, leading to prolonged intracellular retention. Membrane damage and cytoplasmic leakage may result in an influx of nutrients and thus may further promote intracellular germination of the fungus, indicating that
A. fumigatus
has acquired some of the basic properties of intracellular pathogens.
Parallel Evolution of Tobramycin Resistance across Species and Environments
Authors: Scribner Michelle R. , Santos-Lopez Alfonso , Marshall Christopher W. , Deitrick Christopher , Cooper Vaughn S.
Published: May 2020

The rise of antimicrobial resistance is a leading medical threat, motivating efforts to forecast both its evolutionary dynamics and its genetic causes. Aminoglycosides are a major class of antibiotics that disrupt translation, but resistance may occur by a number of mechanisms. Here, we show the repeated evolution of resistance to the aminoglycoside tobramycin in both
P. aeruginosa
and
A. baumannii
via mutations in
fusA1
, encoding elongation factor G, and
ptsP
, encoding the nitrogen-specific phosphotransferase system. Laboratory evolution and whole-population genome sequencing were used to identify these targets, but mutations at identical amino acid positions were also found in published genomes of diverse bacterial species and clinical isolates. We also identified other resistance mechanisms associated with growth in biofilms that likely interfere with drug binding or uptake. Characterizing the evolution of multiple species in the presence of antibiotics can identify new, repeatable causes of resistance that may be predicted and counteracted by alternative treatment.
Decreased, Deformed, Defective—How HIV-1 Vpu Targets Peroxisomes
Authors: Hopfensperger Kristina , Sauter Daniel
Published: May 2020

Peroxisomes are found in essentially all eukaryotic cells and have been described as important hubs in innate sensing and the induction of type III interferons upon viral infection. Nevertheless, it remains poorly investigated how viral pathogens modulate biogenesis or function of peroxisomes to evade innate sensing and restriction. In a recent study, Hobman and colleagues found that the accessory viral protein u (Vpu) of HIV-1 inhibits peroxisome activity by depleting cellular peroxisome pools.
The Killing Mechanism of Teixobactin against Methicillin-Resistant Staphylococcus aureus: an Untargeted Metabolomics Study
Authors: Hussein Maytham , Karas John A. , Schneider-Futschik Elena K. , Chen Fan , Swarbrick James , Paulin Olivia K. A. , Hoyer Daniel , Baker Mark , Zhu Yan , Li Jian , Velkov Tony
Published: May 2020

Antimicrobial resistance is one of the greatest threats to the global health system. It is imperative that new anti-infective therapeutics be developed against problematic “superbugs.” The cyclic depsipeptide teixobactin holds much promise as a new class of antibiotics for highly resistant Gram-positive pathogens (e.g., methicillin-resistant
Staphylococcus aureus
[MRSA]). Understanding its molecular mechanism(s) of action could lead to the design of new compounds with a broader activity spectrum. Here, we describe the first metabolomics study to investigate the killing mechanism(s) of teixobactin against MRSA. Our findings revealed that teixobactin significantly disorganized the bacterial cell envelope, as reflected by a profound perturbation in the bacterial membrane lipids and cell wall biosynthesis (peptidoglycan and teichoic acid). Importantly, teixobactin significantly suppressed the main intermediate
d
-alanyl-
d
-lactate involved in the mechanism of vancomycin resistance in
S. aureus
. These novel results help explain the unique mechanism of action of teixobactin and its lack of cross-resistance with vancomycin.
Supplemental Material: How do basin margins record long-term tectonic and climatic changes?
Authors: Zhang Jinyu
Published: May 2020

Tables S1 and S2, Animations S1–S4, Figure S1, and additional ancient basin-margin examples.
Neonatal outcomes of extremely preterm twins by sex pairing: an international cohort study
Authors: Gagliardi Luigi , Rusconi Franca , Reichman Brian , Adams Mark , Modi Neena , Lehtonen Liisa , Kusuda Satoshi , Vento Maximo , Darlow Brian A , Bassler Dirk , Isayama Tetsuya , Norman Mikael , Håkansson Stellan , Lee Shoo K , Lui Kei , Yang Junmin , Shah Prakeshkumar
Published: May 2020

Objective

Infant boys have worse outcomes than girls. In twins, the ‘male disadvantage’ has been reported to extend to female co-twins via a ‘masculinising’ effect. We studied the association between sex pairing and neonatal outcomes in extremely preterm twins.

Design

Retrospective cohort study

Setting

Eleven countries participating in the International Network for Evaluating Outcomes of Neonates.

Patients

Liveborn twins admitted at 23–29 weeks’ gestation in 2007–2015.

Main outcome measures

We examined in-hospital mortality, grades 3/4 intraventricular haemorrhage or cystic periventricular leukomalacia (IVH/PVL), bronchopulmonary dysplasia (BPD), retinopathy of prematurity requiring treatment and a composite outcome (mortality or any of the outcomes above).

Results

Among 20 924 twins, 38% were from male-male pairs, 32% were from female-female pairs and 30% were sex discordant. We had no information on chorionicity. Girls with a male co-twin had lower odds of mortality, IVH/PVL and the composite outcome than girl-girl pairs (reference group): adjusted OR (aOR) (95% CI) 0.79 (0.68 to 0.92), 0.83 (0.72 to 0.96) and 0.88 (0.79 to 0.98), respectively. Boys with a female co-twin also had lower odds of mortality: aOR 0.86 (0.74 to 0.99). Boys from male-male pairs had highest odds of BPD and composite outcome: aOR 1.38 (1.24 to 1.52) and 1.27 (1.16 to 1.39), respectively.

Conclusions

Sex-related disparities in outcomes exist in extremely preterm twins, with girls having lower risks than boys and opposite-sex pairs having lower risks than same-sex pairs. Our results may help clinicians in assessing risk in this large segment of extremely preterm infants.
Impact of the COVID-19 pandemic on the process and outcome of thrombectomy for acute ischemic stroke
Authors: Yang Bin , Wang Tao , Chen Jian , Chen Yanfei , Wang Yabing , Gao Peng , Li Guilin , Chen Fei , Li Long , Wang Zheng , Zhang Hongqi , Song Haiqing , Ma Qingfeng , Jiao Liqun
Published: May 2020

Background

The novel coronavirus disease 2019 (COVID-19) pandemic is still spreading across the world. Although the pandemic has an all-round impact on medical work, the degree of its impact on endovascular thrombectomy (EVT) for patients with acute ischemic stroke (AIS) is unclear.

Methods

We continuously included AIS patients with large artery occlusion who underwent EVT in a comprehensive stroke center before and during the Wuhan shutdown. The protected code stroke (PCS) for screening and treating AIS patients was established during the pandemic. The efficacy and safety outcomes including the rate of successful reperfusion (defined as modified Thrombolysis In Cerebral Infarction (mTICI) graded 2b or 3) and time intervals for reperfusion were compared between two groups: pre-pandemic and pandemic.

Results

A total of 55 AIS patients who received EVT were included. The baseline characteristics were comparable between the two groups. The time from hospital arrival to puncture (174 vs 125.5 min; p=0.002) and time from hospital arrival to reperfusion (213 vs 172 min; p=0.047) were significantly prolonged in the pandemic group compared with the pre-pandemic group. The rate of successful reperfusion was not significantly different between the two groups (85.7% (n=18) vs 88.2% (n=30); OR 0.971, 95% CI 0.785 to 1.203; p=1.000).

Conclusion

The results of this study suggest a proper PCS algorithm which combines the COVID-19 screening and protection measures could decrease the impact of the disease on the clinical outcomes of EVT for AIS patients to the lowest extent possible during the pandemic.
YAP confers resistance to vandetanib in medullary thyroid cancer
Authors: Wang Huan , Tang Jian , Su Zhiwei
Published: May 2020

Medullary thyroid cancer (MTC) is the third most common thyroid cancer. RET (Rearranged in Transformation) gene mutations are considered as one of the major drivers of MTC. Vandetanib suppresses RET activity, and has shown promise in clinical trials. Unfortunately, acquired resistance to vandetanib has been observed in MTC, although the mechanism was largely unknown. We investigated the critical role of YAP (Yes-Associated Protein) on vandetanib resistance in MTC. For this, TT cells (medullary thyroid cancer cells) were treated with vandetanib for 3 months to generate a vandetanib-resistant cell line (TT-R). We investigated the role of YAP on vandetanib-resistance in TT-R cells by performing cell proliferation and colony formation assays, and examined the antitumor effects of YAP inhibitor and vandetanib in a mouse model of xenografted MTC. The TT-R cells displayed 6-fold higher IC50 to vandetanib than the TT cells. Overexpression of YAP resulted in resistance to vandetanib, whereas knockdown of YAP re-sensitized the TT-R cells to vandetanib. The YAP inhibitor synergized with vandetanib on tumor inhibition. Our results suggest that YAP plays an important role in acquired resistance to vandetanib in MTC, providing basis for combating MTC with YAP inhibitor and vandetanib.
Platinum(IV) complexes of a bulky and exceptionally donating alkyl: 2-adamantyl
Authors: Taullaj Fioralba , Fekl Ulrich , Lough Alan J.
Published: May 2020

The 2-adamantyl (2-Ad) group is a particularly challenging alkyl to install on a transition metal, with the only reported 2-Ad complexes of platinum being those of Pt(II). The question of whether 2-Ad complexes with platinum in the oxidation state +IV can be made and whether they are stable is answered here. The Pt(IV) compound trans-[(bpy)PtMe2(2-Ad)I] (bpy = 2,2′-bipyridine) was synthesized via oxidative addition of iodomethane to [(COD)PtMe(2-Ad)] (COD = 1,5-cyclooctadiene) in the presence of bpy. Iodide abstraction with silver triflate (triflate anion, OTf− = CF3SO3−) produced trans-[(bpy)PtMe2(2-Ad)(OTf)]. Both complexes were unambiguously characterized by 1D NMR (1H, 13C) spectroscopy and X-ray crystallography. Both show evidence for the large steric bulk of the 2-Ad group (through the conformation of the complex adopted) and also for its exceptionally pronounced trans-influence (very long bonds to iodide/triflate trans to adamantyl). Both of the new platinum(IV) adamantyl complexes were extremely stable, even to prolonged heating.
Water stress, sap flow and transpiration for medium and highly drought resistant poplars grown in the semiarid Canadian prairie
Authors: Cutforth H.W. , Wall K.G.
Published: May 2020

Sap flow was measured to determine transpiration rates for CanAm and Walker poplars grown in the semiarid Canadian prairie. CanAm poplars had higher sap flow rates and were better able to supply water to actively growing regions for all water availabilities (well-watered to drought). CanAm poplars were better able to survive drought.
Redesign of Car Body by Reverse Engineering Technique using Steinbichler 3D Scanner and Projet 3D Printer
Authors: Haleem Abid , Javaid Mohd , Goyal Abhishek , Khanam Tarbiya
Published: May 2020

Product designing requires concept development tool like TRIZ to obtain innovative solutions. In this paper, we have applied available concept development and design tool to develop a relationship between the problem definitions, identified as per customer needs, and the design of the products physical parameters complying with the required specifications. Product development techniques like Reverse Engineering, Surface Modeling, and Rapid Prototyping technologies are employed to improve the existing design of a specific problem. These technologies are used for customization of product and are helpful for research and development purpose. In this paper, the outer body of an existing car is redesigned, and we have further created a prototype with improved aerodynamics and futuristic aesthetics. In this Additive Manufacturing (AM) process, Steinbichler 3D Scanner, Projet 3D printer and associated Scanning and printing software are used, by which redesign and associated development process of a car become easy in lesser time and cost.
Security Issues and Challenges for Virtualization Technologies
Authors: Sierra-Arriaga Federico , Branco Rodrigo , Lee Ben
Published: May 2020

Virtualization-based technologies have become ubiquitous in computing. While they provide an easy-to-implement platform for scalable, high-availability services, they also introduce new security issues. Traditionally, discussions on security vulnerabilities in server platforms have been focused on stand-alone (i.e., non-virtualized) environments. For cloud and virtualized platforms, the discussion focuses on the shared usage of resources and the lack of control over the infrastructure. However, the impact virtualization technologies can have on exploit mitigation mechanisms of host machines is often neglected. Therefore, this survey discusses the following issues: first, the security issues and challenges that are introduced by the migration from stand-alone solutions to virtualized environments—special attention is given to the Virtual Machine Monitor, since it is a core component in a virtualized solution; second, the impact (sometimes negative) that these new technologies have on existing security strategies for hosts; third, how virtualization technologies can be leveraged to provide new security mechanisms not previously available.; and, finally, how virtualization technologies can be used for malicious purposes.
Exploiting Cross-session Information for Session-based Recommendation with Graph Neural Networks
Authors: Qiu Ruihong , Huang Zi , Li Jingjing , Yin Hongzhi
Published: May 2020

Different from the traditional recommender system, the session-based recommender system introduces the concept of the
session
, i.e., a sequence of interactions between a user and multiple items within a period, to preserve the user’s recent interest. The existing work on the session-based recommender system mainly relies on mining sequential patterns within individual sessions, which are not expressive enough to capture more complicated dependency relationships among items. In addition, it does not consider the cross-session information due to the anonymity of the session data, where the linkage between different sessions is prevented. In this article, we solve these problems with the graph neural networks technique. First, each session is represented as a graph rather than a linear sequence structure, based on which a novel
F
ull
G
raph
N
eural
N
etwork (FGNN) is proposed to learn complicated item dependency. To exploit and incorporate cross-session information in the individual session’s representation learning, we further construct a
B
roadly
C
onnected
S
ession (BCS) graph to link different sessions and a novel Mask-Readout function to improve session embedding based on the BCS graph. Extensive experiments have been conducted on two e-commerce benchmark datasets, i.e.,
Yoochoose
and
Diginetica
, and the experimental results demonstrate the superiority of our proposal through comparisons with state-of-the-art session-based recommender models.
Enhancing Employer Brand Evaluation with Collaborative Topic Regression Models
Authors: Lin Hao , Zhu Hengshu , Wu Junjie , Zuo Yuan , Zhu Chen , Xiong Hui
Published: May 2020

Employer Brand Evaluation (EBE) is to understand an employer’s unique characteristics to identify competitive edges. Traditional approaches rely heavily on employers’ financial information, including financial reports and filings submitted to the Securities and Exchange Commission (SEC), which may not be readily available for private companies. Fortunately, online recruitment services provide a variety of employers’ information from their employees’ online ratings and comments, which enables EBE from an employee’s perspective. To this end, in this article, we propose a method named Company Profiling–based Collaborative Topic Regression (CPCTR) to collaboratively model both textual (i.e., reviews) and numerical information (i.e., salaries and ratings) for learning latent structural patterns of employer brands. With identified patterns, we can effectively conduct both qualitative opinion analysis and quantitative salary benchmarking. Moreover, a Gaussian processes--based extension, GPCTR, is proposed to capture the complex correlation among heterogeneous information. Extensive experiments are conducted on three real-world datasets to validate the effectiveness and generalizability of our methods in real-life applications. The results clearly show that our methods outperform state-of-the-art baselines and enable a comprehensive understanding of EBE.
RIPE IPmap active geolocation
Authors: Du Ben , Candela Massimo , Huffaker Bradley , Snoeren Alex C. , claffy kc
Published: May 2020

RIPE IPmap is a multi-engine geolocation platform operated by the RIPE NCC. One of its engines, single-radius, uses active geolocation to infer the geographic coordinates of target IP addresses. In this paper, we first introduce the methodology of IPmap's single-radius engine, then we evaluate its accuracy, coverage, and consistency, and compare its results with commercial geolocation databases. We found that 79.5% of single-radius results have city-level accuracy for our ground truth dataset, and 87.0% have city-level consistency or geolocating different interfaces on the same routers. On our coverage evaluation dataset of 26,559 core infrastructure IP addresses, single-radius provided geolocation inferences for 78.5% of them.We offer recommendations to improve the single-radius engine and IPmap platform in general. The main contributions of this paper are to introduce and evaluate the IPmap single-radius engine and to provide a generalized evaluation workflow applicable to historical and future geolocation techniques.
The web is still small after more than a decade
Authors: Hoang Nguyen Phong , Niaki Arian Akhavan , Polychronakis Michalis , Gill Phillipa
Published: May 2020

Understanding web co-location is essential for various reasons. For instance, it can help one to assess the collateral damage that denial-of-service attacks or IP-based blocking can cause to the availability of co-located web sites. However, it has been more than a decade since the first study was conducted in 2007. The Internet infrastructure has changed drastically since then, necessitating a renewed study to comprehend the nature of web co-location.

In this paper, we conduct an empirical study to revisit web co-location using datasets collected from active DNS measurements. Our results show that the web is still small and centralized to a handful of hosting providers. More specifically, we find that more than 60% of web sites are co-located with at least ten other web sites---a group comprising less popular web sites. In contrast, 17.5% of mostly popular web sites are served from their own servers.

Although a high degree of web co-location could make co-hosted sites vulnerable to DoS attacks, our findings show that it is an increasing trend to co-host many web sites and serve them from well-provisioned content delivery networks (CDN) of major providers that provide advanced DoS protection benefits. Regardless of the high degree of web co-location, our analyses of popular block lists indicate that IP-based blocking does not cause severe collateral damage as previously thought.
Validating the Sharing Behavior and Latency Characteristics of the L4S Architecture
Authors: BoruOljira Dejene , Grinnemo Karl-Johan , Brunstrom Anna , Taheri Javid
Published: May 2020

The strict low-latency requirements of applications such as virtual reality, online gaming, etc., can not be satisfied by the current Internet. This is due to the characteristics of classic TCP such as Reno and TCP Cubic which induce high queuing delays when used for capacity-seeking traffic, which in turn results in unpredictable latency. The Low Latency, Low Loss, Scalable throughput (L4S) architecture addresses this problem by combining scalable congestion controls such as DCTCP and TCP Prague with early congestion signaling from the network. It defines a Dual Queue Coupled (DQC) AQM that isolates low-latency traffic from the queuing delay of classic traffic while ensuring the safe co-existence of scalable and classic flows on the global Internet. In this paper, we benchmark the DualPI2 scheduler, a reference implementation of DQC AQM, to validate some of the experimental result(s) reported in the previous works that demonstrate the co-existence of scalable and classic congestion controls and its low-latency service. Our results validate the co-existence of scalable and classic flows using DualPI2 Single queue (SingleQ) AQM, and queue latency isolation of scalable flows using DualPI2 Dual queue (DualQ) AQM. However, the rate or window fairness between DCTCP without fair-queuing (FQ) pacing and TCP Cubic using DualPI2 DualQ AQM deviates from the original results. We attribute the difference in our results and the original results to the sensitivity of the L4S architecture to traffic bursts and the burst sending pattern of the Linux kernel.