bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous Broad Ligament Hematoma after Vaginal Delivery Requiring Hysterectomy
Authors: Varvoutis Megan , Nguyen Nguyen Thao Thi , Grotegut Chad
Published: February 2021

Background Broad ligament hematomas are rare in the setting of vaginal delivery. When they do occur, patients typically present with acute hemodynamic instability. No cases of infected broad ligament hematomas have been reported.

Case A 22-year-old G2 P1011 status post vaginal delivery complicated by chorioamnionitis and pre-eclampsia presented 5 days postpartum with subjective complaints of fever, vomiting, and increased vaginal bleeding. She was treated with antibiotics and uterine evacuation was planned for presumed retained products. After dilation and curettage, the patient was transferred to our facility, as her clinical status did not improve, and was later found to have an infected broad ligament hematoma requiring hysterectomy.

Conclusion Though uncommon, broad ligament hematomas should be considered in postpartum women presenting with anemia and vaginal bleeding, even without hemodynamic instability. Recent intrauterine infections may predispose to hematoma infection.
Model evaluations of multipactor suppression in rectangular waveguides through grooved surfaces and static magnetic field
Authors: Qiu X. , Saed M. A. , Mankowski J. J. , Dickens J. , Neuber A. , Joshi R. P.
Published: February 2021

Mitigation of multipactor in waveguides is of importance, and strategies have included the addition of external fields, materials engineering, or surface modifications. Here, geometry modifications of rectangular waveguide surfaces and the application of an axial magnetic field are investigated for suppressing multipactor growth. A Monte Carlo approach has been used to simulate electron dynamics. The empirical secondary electrons yield is modeled based on a modified Vaughan approach. The electric fields driving electron transport were derived from separate electromagnetic calculations to adequately include field perturbations due to the presence of surface patterns in the rectangular waveguide structure. Combinations of grooves and a DC magnetic field are shown to effectively mitigate multipactor growth at field strengths up to ∼105 V/m. Finding optimal combinations for an arbitrary field and operating frequency requires further work.
A domain wall creation paradigm: Realization for amorphous Fe-based microwires
Authors: Leble Sergey , Rodionova Valeria
Published: February 2021

The creation of a domain wall pair in the magnetic core of amorphous glass-coated bistable microwires with circular cross-section is studied. Energy balance is formulated in the spirit of particle decay, equalizing magnetic field work and energy of two domain walls, emitted in opposite directions. The critical nucleation field is evaluated and compared with observations.
Activation of NF-κB and p300/CBP potentiates cancer chemoimmunotherapy through induction of MHC-I antigen presentation
Authors: Zhou Yixuan , Bastian Ingmar Niels , Long Mark D. , Dow Michelle , Li Weihua , Liu Tao , Ngu Rachael Katie , Antonucci Laura , Huang Jian Yu , Phung Qui T. , Zhao Xi-he , Banerjee Sourav , Lin Xue-Jia , Wang Hongxia , Dang Brian , Choi Sylvia , Karin Daniel , Su Hua , Ellisman Mark H. , Jamieson Christina , Bosenberg Marcus , Cheng Zhang , Haybaeck Johannes , Kenner Lukas , Fisch Kathleen M. , Bourgon Richard , Hernandez Genevive , Lill Jennie R. , Liu Song , Carter Hannah , Mellman Ira , Karin Michael , Shalapour Shabnam
Published: February 2021

Significance

T cells recognize their targets via their T-cell receptors (TCRs), which in the case of CD8
+
T cells bind to MHC-I:antigen complexes on the surface of target cells. Many cancer cells evade immune recognition and killing by down-regulating MHC-I AgPPM. Here, we show how the histone acetyl transferases p300/CBP together with NF-κB epigenetically regulate expression of MHC-I molecules, immunoproteasome subunits, and peptide transporter to enable proper MHC-I antigen presentation. Notably, this pathway is frequently disrupted in human cancers. We now show that certain chemotherapeutics can augment MHC-I antigen presentation via NF-κB and p300/CBP activation, thereby enhancing cancer cell recognition and killing by effector CD8
+
CTLs.
Speaker’s verbal behavior and collective audience responses in Korean political oratory
Authors: Choi Hyangmi , Bull Peter
Published: February 2021

An analysis was conducted of the discourse of South Korean political speakers in relation to collective audience
responses, based on three situational contexts. Results showed marked contextual differences in the formatting of messages used to
invite audience responses. In campaign speeches, explicit (dialogic) rhetorical devices (RDs) occurred most frequently, thereby
supporting Bull and Miskinis’ (2015) hypothesis that such RDs are characteristic of
political speech-making in collectivist far eastern societies. However, this hypothesis was substantively qualified by findings
that (1) in the acceptance and inauguration speeches, implicit RDs were utilized more frequently than explicit (dialogic) RDs, and
(2) in those two contexts, it was non-formatted messages that occurred more frequently than either explicit or implicit RDs
separately.
Topological phase transition induced by band structure modulation in a Chern insulator
Authors: Mondal Sayan , Kapri Priyadarshini , Dey Bashab , Ghosh Tarun Kanti , Basu Saurabh
Published: February 2021

We study a systematic evolution of the topological properties of a Chern insulator upon smooth variation of a hopping parameter (t
1) of the electrons among a pair of nearest neighbour sites on a honeycomb lattice, while keeping the other two hopping terms (t) fixed. In the absence of a Haldane flux, the tuning of t
1 results in gradual shifting of the Dirac cones which eventually merge into one at the M point in the Brillouin zone (BZ) at t
1 = 2t with a gapless semi-Dirac dispersion at low energies. In the presence of a Haldane flux, the system becomes a Chern insulator for t
1 < 2t, but turns gapless at t
1 = 2t with the semi-Dirac dispersion being transformed to an anisotropic Dirac one. The spectrum eventually gaps out and transforms into a trivial insulator for t
1 > 2t. The Chern number phase diagram obtained via integrating the Berry curvature over the BZ shows a gradual shrinking of the ‘topological’ lobes, and vanishes just beyond t
1 = 2t, where a small but a finite Berry curvature still exists. Thus, there is a phase transition from a topological phase to a trivial phase across the semi-Dirac point (t
1 = 2t). The vanishing of the anomalous Hall conductivity plateau and the merger of the chiral edge states with the bulk bands near the M point provide robust support of the observed phase transition.
Synthesis and bioconjugation of alkanethiol-stabilized gold bipyramid nanoparticles
Authors: Abdul-Moqueet Mohammad M , Tovias Leeana , Lopez Priscilla , Mayer Kathryn M
Published: February 2021

Gold bipyramid (GBP) nanoparticles are promising for a range of biomedical applications, including biosensing and surface-enhanced Raman spectroscopy, due to their favorable optical properties and ease of chemical functionalization. Here we report improved synthesis methods, including preparation of gold seed particles with an increased shelf life of ∼1 month, and preparation of GBPs with significantly shortened synthesis time (< 1 h). We also report methods for the functionalization and bioconjugation of the GBPs, including functionalization with alkanethiol self-assembled monolayers (SAMs) and bioconjugation with proteins via carbodiimide cross-linking. Binding of specific antibodies to the nanoparticle-bound proteins was subsequently observed via localized surface plasmon resonance sensing. Rabbit IgG and goat anti-Rabbit IgG antibodies were used as a model system for antibody-antigen interactions. As-synthesized, SAM-functionalized, and bioconjugated bipyramids were characterized using scanning electron microscopy, UV–vis spectroscopy, zeta potential, and dynamic light scattering.
Reading scientists in the high school classroom: peer and teacher mediation
Authors: Pagliarini Cassiano Rezende , Almeida Maria José P M de
Published: February 2021

The role of peer and teacher mediation in discussions about two original scientific texts in the final year of high school in Brazil is explored in this study. A text by James C Maxwell, deals with the characterisation of light as an electromagnetic phenomenon, and refers to the continuous manner of the distribution of energy by radiation in space. The other, by Ludwig Boltzmann, is about thermodynamics in its probabilistic conception and some of its consequences for the comprehension of the nature of heat. We analyse some of the students’ interpretations using a version of discourse analysis, developed in Brazil following the French tradition of Michel Pêcheux. We highlight interactions that contribute to the reading of the texts and the mediations of both the teacher and peers that promote the establishment of relevant meanings about physics concepts. The appropriation of their statements about the content is observed in this communicative approach. We contribute to the investigation of physics teaching using strategies informed by a humane scientific and cultural educational perspective in high schools.
Bioimpedance analysis as a tool for hemodynamic monitoring: overview, methods and challenges
Authors: Anand Gautam , Yu Yang , Lowe Andrew , Kalra Anubha
Published: February 2021

Recent advances in hemodynamic monitoring have seen the advent of non-invasive methods which offer ease of application and improve patient comfort. Bioimpedance Analysis or BIA is one of the currently employed non-invasive techniques for hemodynamic monitoring. Impedance Cardiography (ICG), one of the implementations of BIA, is widely used as a non-invasive procedure for estimating hemodynamic parameters such as stroke volume (SV) and cardiac output (CO). Even though BIA is not a new diagnostic technique, it has failed to gain consensus as a reliable measure of hemodynamic parameters. Several devices have emerged for estimating CO using ICG which are based on evolving methodologies and techniques to calculate SV. However, the calculations are generally dependent on the electrode configurations (whole body, segmental or localised) as well as the accuracy of different techniques in tracking blood flow changes. Blood volume changes, concentration of red blood cells, pulsatile velocity profile and ambient temperature contribute to the overall conductivity of blood and hence its impedance response during flow. There is a growing interest in investigating limbs for localised BIA to estimate hemodynamic parameters such as pulse wave velocity. As such, this paper summarises the current state of hemodynamic monitoring through BIA in terms of different configurations and devices in the market. The conductivity of blood flow has been emphasized with contributions from both volume and velocity changes during flow. Recommendations for using BIA in hemodynamic monitoring have been mentioned highlighting the suitable range of frequencies (1 kHz–1 MHz) as well as safety considerations for a BIA setup. Finally, current challenges in using BIA such as geometry assumption and inaccuracies have been discussed while mentioning potential advantages of a multi-frequency analysis to cover all the major contributors to blood’s impedance response during flow.
Photoluminescence and temperature dependent polarization response of MgTiO3 synthesised via solid state reaction
Authors: Chattopadhyay K K , Sharma A K , Banerjee D
Published: February 2021

Synthesis of MgTiO3 via solid state reaction with excess MgO has been reported. The as prepared sample was characterised via x-ray diffraction (XRD), field emission scanning electron microscope (FESEM), high resolution transmission electron microscope (HRTEM), UV-Vis-NIR spectroscopy and photoluminescence spectroscopy. XRD pattern of the sample tells that the MgTiO3 is of single phase which is mainly due to the use of excess of MgO and can be indexed in a hexagonal unit cell. FESEM and HRTEM study shows the structure of the sample. The polarisation responses of the sample under applied electric field have been studied at different temperatures. The enhancement of the area of the polarisation-electric field curve with measurement temperature suggest an increased dielectric loss for the sample. The PL property has also been studied for different excitation energies and the result has been compared with optical gap of the sample as obtained from UV-Vis transmission spectra. Efforts have been made to correlate the two properties of the sample.
Photocatalytic properties of nanosized zinc ferrite and zinc chromite
Authors: Shabelskaya N P , Egorova M A , Vasileva E V , Polozhentsev O E
Published: February 2021

A simple one-step synthesis of developed surface zinc ferrite is proposed (S
BET = 453.1 m2 g−1). The formation of zinc ferrite, zinc chromite (S
BET = 53.6 m2 g−1), and mixed zinc ferrite-chromite (S
BET = 37.4 m2 g−1) structures is studied. The resulting materials are analysed using x-ray phase and x-ray fluorescence analysis, IR spectrometry, electron microscopy, TGA and BET method. Single-phase sample formation mechanism is proposed, which includes transition element cation chelate complex formation stage in the presence of citric acid and subsequent thermal decomposition of the complexes formed. The synthesised materials exhibited photocatalytic activity in the decomposition of an organic dye under the action of hydrogen peroxide. The highest catalytic activity is demonstrated by zinc ferrite in acidic medium; the calculated reaction rate constant is 0.010 min−1 for ZnFe2O4, 0.008 min−1 for ZnFeCrO4, 0.007 min−1 for ZnCr2O4. The results can be applied to obtain materials suitable for wastewater treatment processes at industrial enterprises where organic dyes are used in production cycles.
Delayed health consequences of COVID-19 lockdown in an older adult
Authors: Aroos Rana , Wong Beatrix Ling Ling , Merchant Reshma Aziz
Published: February 2021

We report a case of a retired school teacher who presented with rapid cognitive and functional decline following the COVID-19 lockdown period that was diagnosed as worsening depression by referring physician. This highlights the potentially life-threatening consequences of delayed diagnosis and management of delirium, an often reversible syndrome, due to lockdown restrictions. As the pandemic outlives its initial projections, its downstream impact on an already vulnerable population continues to emerge.
Linking key dimensions of plant phenotypic diversity. A commentary on: ‘Mating systems and life history’
Authors: Pannell John R
Published: February 2021

This article comments on:

Yue Ma, Spencer C. H. Barrett, Fang-Yuan Wang, Jun-Chen Deng and Wei-Ning Bai, Do annual and perennial populations of an insect-pollinated plant species differ in mating system?, Annals of Botany, Volume 127, Issue 7, 4 June 2021, Pages 853–864, 10.1093/aob/mcaa178
Comparative analysis of root sprouting and its vigour in temperate herbs: anatomical correlates and environmental predictors
Authors: Bartušková Alena , Filartiga Arinawa Liz , Herben Tomáš , Qian Jianqiang , Klimešová Jitka
Published: February 2021

Background and Aims

Root sprouting (RS), i.e. the ability to form adventitious buds on roots, is an important form of clonal growth in a number of species, and serves as both a survival strategy and a means of spatial expansion, particularly in plants growing in severely and recurrently disturbed habitats. Occurrence and/or success of plants in severely and recurrently disturbed habitats are determined by two components, namely the ability to produce adventitious buds on roots and the vigour of their production. As mechanisms behind different magnitudes of RS remain unclear, our study investigates: (1) whether the presence or absence of specific tissues in roots can promote or limit RS; and (2) whether there is some relationship between RS ability, RS vigour and species niche.

Methods

We studied RS ability together with RS vigour in 182 Central European herbaceous species under controlled experimental conditions. We used phylogenetic logistic regressions to model the presence of RS, RS vigour, the relationship between RS and anatomical traits and the relationship between RS and parameters of species niches.

Key Results

A quarter of herbs examined were able to produce adventitious buds on roots. They were characterized by their preference for open dry habitats, the presence of secondary root thickening and the occurrence of sclerified cortical cells in roots. Root sprouting vigour was not associated with any specific anatomical pattern, but was correlated with the environmental niches of different species, indicating that preferred disturbed and dry habitats might represent a selection pressure for more vigorous root sprouters than undisturbed and wet habitats.

Conclusions

Our study shows that sprouting from roots is quite common in temperate dicotyledonous herbs. Two components of RS – ability and vigour – should be considered separately in future studies. We would also like to focus more attention on RS in herbs from other regions as well as on external forces and internal mechanisms regulating evolution and the functions of RS in both disturbed and undisturbed habitats.
Resolving páramoPoa(Poaceae): morphometric and phylogenetic analysis of the ‘Cucullatacomplex’ of north-west South America
Authors: Sylvester Steven P , Soreng Robert J , Gilliespie Lynn J
Published: February 2021

Species delimitation in the Poa taxa of the ‘Cucullata complex’ from the páramos of north-west South America, morphologically defined by open panicles and webbed calluses, among other characters, has been complicated by their large morphological variability coupled with a lack of available taxonomic treatments. Using multivariate morphometric and phylogenetic analyses, distinct groupings of taxa were identified including the new páramo taxa, P. bricenoi sp. nov. from Venezuela and P. cucullata subsp. cucullatella subsp. nov. from Ecuador, which are described and illustrated. Poa scabrivaginata is also presented as a new record for Ecuador and páramo vegetation in general. Based on the results from this study, updated descriptions and images are also presented for P. chirripoensis, P. cucullata s.s., P. petrosa and P. scabrivaginata, and an identification key is provided for the species of the Cucullata complex and other open-panicled Poa spp. from Ecuador, Colombia and Venezuela.
Shorter and Longer Courses of Antibiotics for Common Infections and the Association With Reductions of Infection-Related Complications Including Hospital Admissions
Authors: Palin Victoria , Welfare William , Ashcroft Darren M , van Staa Tjeerd Pieter
Published: February 2021

Background

Antimicrobial resistance is a serious global health concern that emphasizes completing treatment course. Recently, the effectiveness of short versus longer antibiotic courses has been questioned. This study investigated the duration of prescribed antibiotics, their effectiveness, and associated risk of infection-related complications.

Methods

Clinical Practice Research Datalink identified 4 million acute infection episodes prescribed an antibiotic in primary care between January 2014—June 2014, England. Prescriptions were categorized by duration. Risk of infection-related hospitalizations within 30 days was modelled overall and by infection type. Risk was assessed immediately after or within 30 days follow-up to measure confounders given similar and varying exposure, respectively. An interaction term with follow-up time assessed whether hazard ratios (HRs) remained parallel with different antibiotic durations.

Results

The duration of antibiotic courses increased over the study period (5.2–19.1%); 6–7 days were most common (66.9%). Most infection-related hospitalizations occurred with prescriptions of 8–15 days (0.21%), accompanied by greater risk of infection-related complications compared to patients who received a short prescription (HR: 1.75 [95% CI: 1.54–2.00]). Comparing HRs in the first 5 days versus remaining follow-up showed longer antibiotic courses were no more effective than shorter courses (1.02 [95% CI: 0.90–1.16] and 0.92 [95% CI: 0.75–1.12]). No variation by infection-type was observed.

Conclusions

Equal effectiveness was found between shorter and longer antibiotic courses and the reduction of infection-related hospitalizations. Stewardship programs should recommend shorter courses of antibiotics for acute infections. Further research is required for treating patients with a complex medical history.

Summary

Prescribing of longer courses increased over the study period. The majority of hospitalizations occurred for patients receiving longer courses. Risk of developing a complication (immediate vs remaining follow-up) found longer courses were no more effective than shorter courses.
Ceftazidime-Avibactam Use for Klebsiella pneumoniae Carbapenemase–Producing K. pneumoniae Infections: A Retrospective Observational Multicenter Study
Authors: Tumbarello Mario , Raffaelli Francesca , Giannella Maddalena , Mantengoli Elisabetta , Mularoni Alessandra , Venditti Mario , De Rosa Francesco Giuseppe , Sarmati Loredana , Bassetti Matteo , Brindicci Gaetano , Rossi Marianna , Luzzati Roberto , Grossi Paolo Antonio , Corona Alberto , Capone Alessandro , Falcone Marco , Mussini Cristina , Trecarichi Enrico Maria , Cascio Antonio , Guffanti Elena , Russo Alessandro , De Pascale Gennaro , Tascini Carlo , Gentile Ivan , Losito Angela Raffaella , Bussini Linda , Corti Giampaolo , Ceccarelli Giancarlo , Corcione Silvia , Compagno Mirko , Giacobbe Daniele Roberto , Saracino Annalisa , Fantoni Massimo , Antinori Spinello , Peghin Maddalena , Bonfanti Paolo , Oliva Alessandra , De Gasperi Andrea , Tiseo Giusy , Rovelli Cristina , Meschiari Marianna , Shbaklo Nour , Spanu Teresa , Cauda Roberto , Viale Pierluigi
Published: February 2021

Background

A growing body of observational evidence supports the value of ceftazidime-avibactam (CAZ-AVI) in managing infections caused by carbapenem-resistant Enterobacteriaceae.

Methods

We retrospectively analyzed observational data on use and outcomes of CAZ-AVI therapy for infections caused by Klebsiella pneumoniae carbapenemase–producing K. pneumoniae (KPC-Kp) strains. Multivariate regression analysis was used to identify variables independently associated with 30-day mortality. Results were adjusted for propensity score for receipt of CAZ-AVI combination regimens versus CAZ-AVI monotherapy.

Results

The cohort comprised 577 adults with bloodstream infections (n = 391) or nonbacteremic infections involving mainly the urinary tract, lower respiratory tract, and intra-abdominal structures. All received treatment with CAZ-AVI alone (n = 165) or with ≥1 other active antimicrobials (n = 412). The all-cause mortality rate 30 days after infection onset was 25% (146/577). There was no significant difference in mortality between patients managed with CAZ-AVI alone and those treated with combination regimens (26.1% vs 25.0%, P = .79). In multivariate analysis, mortality was positively associated with presence at infection onset of septic shock (P = .002), neutropenia (P < .001), or an INCREMENT score ≥8 (P = .01); with lower respiratory tract infection (LRTI) (P = .04); and with CAZ-AVI dose adjustment for renal function (P = .01). Mortality was negatively associated with CAZ-AVI administration by prolonged infusion (P = .006). All associations remained significant after propensity score adjustment.

Conclusions

CAZ-AVI is an important option for treating serious KPC-Kp infections, even when used alone. Further study is needed to explore the drug’s seemingly more limited efficacy in LRTIs and potential survival benefits of prolonging CAZ-AVI infusions to ≥3 hours.
Paclitaxel mitigates structural alterations and cardiac conduction system defects in a mouse model of Hutchinson–Gilford progeria syndrome
Authors: Macías Álvaro , Díaz-Larrosa J Jaime , Blanco Yaazan , Fanjul Víctor , González-Gómez Cristina , Gonzalo Pilar , Andrés-Manzano María Jesús , da Rocha Andre Monteiro , Ponce-Balbuena Daniela , Allan Andrew , Filgueiras-Rama David , Jalife José , Andrés Vicente
Published: February 2021

Aims

Hutchinson–Gilford progeria syndrome (HGPS) is an ultrarare laminopathy caused by expression of progerin, a lamin A variant, also present at low levels in non-HGPS individuals. HGPS patients age and die prematurely, predominantly from cardiovascular complications. Progerin-induced cardiac repolarization defects have been described previously, although the underlying mechanisms are unknown.

Methods and results

We conducted studies in heart tissue from progerin-expressing LmnaG609G/G609G (G609G) mice, including microscopy, intracellular calcium dynamics, patch-clamping, in vivo magnetic resonance imaging, and electrocardiography. G609G mouse cardiomyocytes showed tubulin-cytoskeleton disorganization, t-tubular system disruption, sarcomere shortening, altered excitation–contraction coupling, and reductions in ventricular thickening and cardiac index. G609G mice exhibited severe bradycardia, and significant alterations of atrio-ventricular conduction and repolarization. Most importantly, 50% of G609G mice had altered heart rate variability, and sinoatrial block, both significant signs of premature cardiac aging. G609G cardiomyocytes had electrophysiological alterations, which resulted in an elevated action potential plateau and early afterdepolarization bursting, reflecting slower sodium current inactivation and long Ca+2 transient duration, which may also help explain the mild QT prolongation in some HGPS patients. Chronic treatment with low-dose paclitaxel ameliorated structural and functional alterations in G609G hearts.

Conclusions

Our results demonstrate that tubulin-cytoskeleton disorganization in progerin-expressing cardiomyocytes causes structural, cardiac conduction, and excitation–contraction coupling defects, all of which can be partially corrected by chronic treatment with low dose paclitaxel.
Climate change, weather shocks, and price convergence in pre-industrial Germany
Authors: Albers Hakon , Pfister Ulrich
Published: February 2021

Market integration of European inland regions such as Germany caught up on North-Western Europe from the seventeenth century onwards. As many studies rely on grain prices and the pre-industrial era was a period of climate change, a relevant question is in how far changing weather shocks impact on the measurement of convergence trends. We create a new high-quality grain price dataset and apply four methodologies to quantify market integration robust to weather shocks and climate change. Population growth and river transport turn out as plausible explanations for price convergence rather than climate change.
Complex pleiotropic genetic architecture of evolved heat stress and oxidative stress resistance in the nematodeCaenorhabditis remanei
Authors: O’Connor Christine H , Sikkink Kristin L , Nelson Thomas C , Fierst Janna L , Cresko William A , Phillips Patrick C
Published: February 2021

The adaptation of complex organisms to changing environments has been a central question in evolutionary quantitative genetics since its inception. The structure of the genotype–phenotype maps is critical because pleiotropic effects can generate widespread correlated responses to selection and potentially restrict the extent of evolutionary change. In this study, we use experimental evolution to dissect the genetic architecture of natural variation for acute heat stress and oxidative stress response in the nematode Caenorhabiditis remanei. Previous work in the classic model nematode Caenorhabiditis elegans has found that abiotic stress response is controlled by a handful of genes of major effect and that mutations in any one of these genes can have widespread pleiotropic effects on multiple stress response traits. Here, we find that acute heat stress response and acute oxidative response in C. remanei are polygenic, complex traits, with hundreds of genomic regions responding to selection. In contrast to expectation from mutation studies, we find that evolved acute heat stress and acute oxidative stress response for the most part display independent genetic bases. This lack of correlation is reflected at the levels of phenotype, gene expression, and in the genomic response to selection. Thus, while these findings support the general view that rapid adaptation can be generated by changes at hundreds to thousands of sites in the genome, the architecture of segregating variation is likely to be determined by the pleiotropic structure of the underlying genetic networks.
Selection into shift work is influenced by educational attainment and body mass index: a Mendelian randomization study in the UK Biobank
Authors: Daghlas Iyas , Richmond Rebecca C , Lane Jacqueline M , Dashti Hassan S , Ollila Hanna M , Schernhammer Eva S , Smith George Davey , Rutter Martin K , Saxena Richa , Vetter Céline
Published: February 2021

Background

Shift work is associated with increased cardiometabolic disease risk. This observation may be partly explained by cardiometabolic risk factors having a role in the selection of individuals into or out of shift work. We performed Mendelian randomization (MR) analyses in the UK Biobank (UKB) to test this hypothesis.

Methods

We used genetic risk scores (GRS) to proxy nine cardiometabolic risk factors and diseases (including educational attainment, body mass index (BMI), smoking, and alcohol consumption), and tested associations of each GRS with self-reported frequency of current shift work among employed UKB participants of European ancestry (n = 190 573). We used summary-level MR sensitivity analyses to assess robustness of the identified effects, and we tested whether effects were mediated through sleep timing preference.

Results

Genetically instrumented liability to lower educational attainment (odds ratio (OR) per 3.6 fewer years in educational attainment = 2.40, 95% confidence interval (CI) = 2.22–2.59, P = 4.84 × 10–20) and higher body mass index (OR per 4.7 kg/m2 higher BMI = 1.30, 95% CI = 1.14–1.47, P = 5.85 × 10–5) increased odds of reporting participation in frequent shift work. Results were unchanged in sensitivity analyses allowing for different assumptions regarding horizontal pleiotropy. No selection effects were evident for the remaining exposures, nor for any exposures on selection out of shift work. Sleep timing preference did not mediate the effects of BMI and educational attainment on selection into shift work.

Conclusions

Liability to lower educational attainment and higher BMI may influence selection into shift work. This phenomenon may bias epidemiological studies of shift work that are performed in the UKB.
Hamiltonian Floer Theory for Nonlinear Schrödinger Equations and the Small Divisor Problem
Authors: Fabert Oliver
Published: February 2021

We prove the existence of infinitely many time-periodic solutions of nonlinear Schrödinger equations using pseudo-holomorphic curve methods from Hamiltonian Floer theory. For the generalization of the Gromov–Floer compactness theorem to infinite dimensions, we show how to solve the arising small divisor problem by combining elliptic methods with results from the theory of diophantine approximations.
Role of the PhoPQ two-component regulatory system in the β-lactam resistance ofStenotrophomonas maltophilia
Authors: Huang Hsin-Hui , Wu Bo-Kuan , Li Li-Hua , Lin Yi-Tsung , Yang Tsuey-Ching
Published: February 2021

Background

Stenotrophomonas maltophilia, an opportunistic pathogen, is intrinsically resistant to most β-lactams except ceftazidime and ticarcillin/clavulanate, due to the inducibly expressed L1 and L2 β-lactamases. A two-component regulatory system (TCS) allows organisms to sense and respond to changes in different environmental conditions. The PhoPQ TCS of S. maltophilia plays regulatory roles in antibiotic susceptibility, physiology, stress adaption and virulence. Inactivation of S. maltophilia phoPQ increases β-lactam susceptibility.

Objectives

To elucidate the PhoPQ-regulating mechanism for β-lactam resistance.

Methods

The candidate genes responsible for the ΔphoPQ-mediated β-lactam resistance compromise were identified by transcriptome analysis and verified by quantitative RT–PCR and complementation assay. Etest was used to assess β-lactam susceptibility. The phosphorylation level of the PhoP protein was determined by Phos-tag SDS-PAGE and western blotting. A β-lactam influx assay was used to investigate the influx efficiency of a β-lactam.

Results

PhoPQ deletion down-regulated the expression of mltD1 and slt, attenuated the induced β-lactamase activity and then compromised the β-lactam resistance. Complementation of mutant phoPQ with mltD1 or slt genes partially reverted the induced β-lactamase activity and β-lactam resistance. The PhoPQ TCS was activated in logarithmically grown KJ cells and was further activated by low magnesium, but not by a β-lactam. However, low-magnesium-mediated PhoPQ activation hardly made an impact on β-lactam resistance enhancement. Furthermore, PhoPQ inactivation altered the outer membrane permeability and increased the influx of a β-lactam.

Conclusions

The PhoPQ TCS is activated to some extent in physiologically grown S. maltophilia. Inactivation of phoPQ attenuates the expression of mltD1 and slt, and increases β-lactam influx, both synergically contributing to β-lactam resistance compromise.
Utility of 30-Day Readmission Metrics in the Burn Population: Navigating Quality Metric Limitations in Special Populations
Authors: Prindeze Nicholas J , Shupp Jeffrey W , Johnson Laura S
Published: February 2021

Hospital readmission data may be a useful tool in identifying risk factors leading to higher costs of care or poorer overall outcomes. Several studies have emerged utilizing these datasets to examine the trauma and burn population, which have been unable to distinguish planned from unplanned readmissions. The 2014 Nationwide Readmissions Database was queried for 363 burn-specific ICD-9 DX codes and filtered by age and readmission status to capture the adult burn population. Additionally, burn-related excision and grafting procedures were filtered from 25 ICD-9 SG codes to distinguish planned readmissions. A total of 26,719 burn patients were identified with 781 all-cause unscheduled 30-day readmissions. Further filtering by burn-related excision and grafting procedures then identified 468 patients undergoing a burn-related excision and grafting procedure on readmission, reducing the dataset to 313 patients and identifying up to 60% of readmissions as possibly improperly coded planned readmissions. From this dataset, nonoperative management on initial admission was found to have the strongest correlation with readmission (OR 5.00; 3.33–7.14). Notably corrected data, when stratified by annual burn patient admission volume, identified a significant likelihood of readmission (OR 4.57; 2.15–9.70) of centers receiving the lowest annual number of burn patients, which was not identified in the unfiltered dataset. Healthcare performance statistics may be a powerful metric when utilized appropriately; however, these databases must be carefully applied to small and special populations. This study has determined that as many as 60% of burn patient readmissions included in prior studies may be improperly coded planned readmissions.
Gastroduodenal amyloidosis: a case report and review of literature
Authors: Almushait Youssef B , Syed Faaezuddin , Abbasi Safwan U , Alhussaini Hussah F , Alsohaibani Fahad I
Published: February 2021

Amyloidosis is a disorder characterized by deposition of abnormally folded proteins in the extracellular space of various tissues and organs, possibly leading to their dysfunction. In the majority of cases, amyloidosis presents with systemic involvement including the gastrointestinal tract; however, localized gastroduodenal amyloidosis is rare. We report a case of gastroduodenal amyloidosis in a 36-year-old male with multiple comorbidities who presented with right upper quadrant abdominal pain. Reports of gastroduodenal amyloidosis and other relevant literature were also reviewed and discussed alongside this case.
Phloem loading in rice leaves depends strongly on the apoplastic pathway
Authors: Wang Gaopeng , Wu Yue , Ma Li , Lin Yan , Hu Yuxiang , Li Mengzhu , Li Weiwei , Ding Yanfeng , Chen Lin
Published: February 2021

Phloem loading is the first step in sucrose transport from source leaves to sink organs. The phloem loading strategy in rice remains unclear. To determine the potential phloem loading mechanism in rice, yeast invertase (INV) was overexpressed by a 35S promoter specifically in the cell wall to block sugar transmembrane loading in rice. The transgenic lines exhibited obvious phloem loading suppression characteristics accompanied by the accumulation of sucrose and starch, restricted vegetative growth and decreased grain yields. The decreased sucrose exudation rate with p-chloromercuribenzenesulfonic acid (PCMBS) treatment also indicated that rice actively transported sucrose into the phloem. OsSUT1 (SUCROSE TRANSPORTER 1) showed the highest mRNA levels of the plasma membrane-localized OsSUTs in source leaves. Cross sections of the OsSUT::GUS transgenic plants showed that the expression of OsSUT1 and OsSUT5 occurred in the phloem companion cells. Rice ossut1 mutants showed reduced growth and grain yield, supporting the hypothesis of OsSUT1 acting in phloem loading. Based on these results, we conclude that apoplastic phloem loading plays a major role in the export of sugar from rice leaves.
Auxin and gibberellin signaling cross-talk promotes hypocotyl xylem expansion and cambium homeostasis
Authors: Ben-Targem Mehdi , Ripper Dagmar , Bayer Martin , Ragni Laura
Published: February 2021

During secondary growth, the thickening of plant organs, wood (xylem) and bast (phloem) is continuously produced by the vascular cambium. In Arabidopsis hypocotyl and root, we can distinguish two phases of secondary growth based on cell morphology and production rate. The first phase, in which xylem and phloem are equally produced, precedes the xylem expansion phase in which xylem formation is enhanced and xylem fibers differentiate. It is known that gibberellins (GA) trigger this developmental transition via degradation of DELLA proteins and that the cambium master regulator BREVIPEDICELLUS/KNAT1 (BP/KNAT1) and receptor like kinases ERECTA and ERL1 regulate this process downstream of GA. However, our understanding of the regulatory network underlying GA-mediated secondary growth is still limited. Here, we demonstrate that DELLA-mediated xylem expansion in Arabidopsis hypocotyl is mainly achieved through DELLA family members RGA and GAI, which promote cambium senescence. We further show that AUXIN RESPONSE FACTOR 6 (ARF6) and ARF8, which physically interact with DELLAs, specifically repress phloem proliferation and induce cambium senescence during the xylem expansion phase. Moreover, the inactivation of BP in arf6 arf8 background revealed an essential role for ARF6 and ARF8 in cambium establishment and maintenance. Overall, our results shed light on a pivotal hormone cross-talk between GA and auxin in the context of plant secondary growth.
MALDI-TOF-MS Analysis in the Discovery and Identification of the Serum Peptide Pattern of Pancreatic Ductal Adenocarcinoma
Authors: Huang Yuan , Chen Feng , Zhang Linglin , Lv Qian , Yan Jun , Cui Wei
Published: February 2021

Objective

To explore the application of serum peptidomics in the early diagnosis of pancreatic ductal adenocarcinoma (PDAC).

Methods

The serum specimens from 176 patients with PDAC and 158 healthy control patients were subjected to matrix-assisted laser desorption ionization time-of-flight mass spectrometry to obtain serum peptide profiles. Next, a classification model by differentiated peptides was established and verified to distinguish the 2 groups. Finally, the peptides were identified by tandem mass spectrometry.

Results

A classification model was established by 13 peptides. For patients with PDAC in the early stage, the sensitivity and specificity of the model reached 100% and 96.7%, respectively. The amino acid sequences of the 13 peptides were then determined and the types of proteins were identified, including platelet basic protein, fibrinogen alpha, complement C3, and secreted frizzled-related protein 4. Some of the 13 peptides could be potential PDAC biomarkers.

Conclusion

Serum peptidomics may have potential application in the early diagnosis of PDAC.
Understanding the Middle East through the eyes of Japan’s Newspapers: A topic modelling and sentiment analysis approach
Authors: Ghasiya Piyush , Okamura Koji
Published: February 2021

For Japan—a country that has always been described with virtually no major natural resources such as oil, gas, and coal—the Middle Eastern region has a special place in its economic and foreign policy. In 2017, 39% of Japan’s energy came from oil, and 87% of Japan’s imported oil came from the Middle East, predominantly Saudi Arabia and the UAE. The above facts are enough to discern the critical significance of the Middle Eastern region for Japan. For Japan to have an unhindered supply of oil and other natural resources, it is pertinent that this region remains peaceful. In this scenario, the Middle East-related articles in Japan’s newspapers can help understand Japan’s perspective towards the Middle East. This paper would first apply the topic modelling approach non-negative matrix factorization (NMF) on Middle East-related articles from three newspapers of Japan. After discovering crucial topics, we would utilize traditional supervised machine learning algorithms to determine the overall and topic-specific sentiments from the collected headlines. Our topic modelling results discovered that the Japanese media widely reported issues like Islamic State, the refugee crisis, the Syrian civil war, Qasem Soleimani killing, and Iran nuclear deal. Further, the news related to Saudi Arabia, Syria, and Trump garnered high negative sentiment.
Richness, abundance and spatial heterogeneity of gastropods and bivalves in coral ecosystems across the Mexican Tropical Pacific
Authors: Barrientos-Luján Norma Arcelia , Rodríguez-Zaragoza Fabián Alejandro , López-Pérez Andrés
Published: February 2021

The diversity of gastropods and bivalves, total mollusc richness and total mollusc abundance were analysed for three substrates (coral, rock and sand) in the coral and reef ecosystems of the Mexican Tropical Pacific (MTP). Up to 3,828 individuals (70% gastropods and 30% bivalves), belonging to 209 species (146 gastropods and 63 bivalves), were identified; this is one of the most diverse molluscan faunas (2.77 species/m2) associated with reef systems in the MTP. Evaluation of the sampling effort demonstrated that 80% of gastropod species and 93% of bivalve species inhabiting the reef system were recovered. The highest abundance occurred in the coral substrate (1,939 individuals), while the highest species richness was found on the rock substrate (131 species). The analysis showed that the greatest spatial variation in total mollusc, gastropod and bivalve diversity occurred among different substrates within individual localities, with minor differences among assemblages with increasing spatial scale reflecting the relative homogeneity of the molluscan fauna in the study area. While the gastropods Conus nux, Steironepion piperatum and Muricopsis zeteki accounted for differences among different regions, and Vermicularia pellucida eburnea and Bostrycapulus aculeatus accounted for differences among states, the abundances of M. zeteki, B. aculeatus and V. pellucida eburnea were related to differences in diversity at the scale of individual localities. Among bivalves, Leiosolenus aristatus, L. plumula and Gastrochaena ovata accounted for differences between regions, states and localities, respectively. Overall, the study shows that species composition is influenced by both the substrate and the geographical location of assemblages. This indicates that conservation strategies should address preserving habitat heterogeneity at local scales in the study area.
Frustrated folding of guanine quadruplexes in telomeric DNA
Authors: Carrino Simone , Hennecker Christopher D , Murrieta Ana C , Mittermaier Anthony
Published: February 2021

Human chromosomes terminate in long, single-stranded, DNA overhangs of the repetitive sequence (TTAGGG)n. Sets of four adjacent TTAGGG repeats can fold into guanine quadruplexes (GQ), four-stranded structures that are implicated in telomere maintenance and cell immortalization and are targets in cancer therapy. Isolated GQs have been studied in detail, however much less is known about folding in long repeat sequences. Such chains adopt an enormous number of configurations containing various arrangements of GQs and unfolded gaps, leading to a highly frustrated energy landscape. To better understand this phenomenon, we used mutagenesis, thermal melting, and global analysis to determine stability, kinetic, and cooperativity parameters for GQ folding within chains containing 8–12 TTAGGG repeats. We then used these parameters to simulate the folding of 32-repeat chains, more representative of intact telomeres. We found that a combination of folding frustration and negative cooperativity between adjacent GQs increases TTAGGG unfolding by up to 40-fold, providing an abundance of unfolded gaps that are potential binding sites for telomeric proteins. This effect was most pronounced at the chain termini, which could promote telomere extension by telomerase. We conclude that folding frustration is an important and largely overlooked factor controlling the structure of telomeric DNA.
The origin and development of firm management
Authors: Giorcelli Michela
Published: February 2021

This paper examines the historical origin and diffusion of management practices. Despite their centrality in modern world, the concepts of ‘management’ developed fairly recently. Only with the Industrial Revolution, due to the increased firm size, owners needed a management structure to coordinate activities across different plants. Management soon became the subject of numerous studies in economics, sociology, and psychology to maximize firm productivity. The first large-scale programme of management practices diffusion was developed in the US during the Second World War: offering such training to US firms involved in war production boosted their performance for at least 10 years. After the Second World War, the US exported its management principles to Europe, where they have large and persistent effects on small firm productivity, and to Japan, where they interacted with the local economic conditions and originated the ‘kaizen Japanese management’, which aims at ‘continuous improvement’ in firm performance.