bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Natural Mutations Responsible for Altered Infection Phenotypes of Salmonella enterica Clinical Isolates by Using Cell Line Infection Screens
Authors: Kolenda Rafał , Burdukiewicz Michał , Wimonć Marcjanna , Aleksandrowicz Adrianna , Ali Aamir , Szabo Istvan , Tedin Karsten , Bartholdson Scott Josefin , Pickard Derek , Schierack Peter
Published: November 2020

Salmonella
is a foodborne pathogen affecting over 200 million people and resulting in over 200,000 fatal cases per year. Its adhesion to and invasion into intestinal epithelial cells represent one of the first and key steps in the pathogenesis of salmonellosis. Still, around 35 to 40% of bacterial genes have no experimentally validated function, and their contribution to bacterial virulence, including adhesion and invasion, remains largely unknown. Therefore, the significance of this study is in the identification of new genes or gene allelic variants previously not associated with adhesion and invasion. It is well established that blocking adhesion and/or invasion would stop or hamper bacterial infection; therefore, the new findings from this study could be used in future developments of anti-
Salmonella
therapy targeting genes involved in these key processes. Such treatment could be a valuable alternative, as the prevalence of antibiotic-resistant bacteria is increasing very rapidly.
Chikungunya Virus Replication Rate Determines the Capacity of Crossing Tissue Barriers in Mosquitoes
Authors: Merwaiss Fernando , Filomatori Claudia V. , Susuki Yasutsugu , Bardossy Eugenia S. , Alvarez Diego E. , Saleh María-Carla
Published: November 2020

It is well established that selective pressures in mosquito vectors impose population bottlenecks for arboviruses. Here, we used a CHIKV Caribbean lineage mutant carrying a deletion in the 3′ UTR to study host-virus interactions
in vivo
in the epidemic mosquito vector
Aedes aegypti
. We found that the mutant virus had a delayed replication rate in mosquitoes, which lengthened the extrinsic incubation period (EIP) and reduced fitness relative to the wild-type virus. As a result, the mutant virus displayed a reduced capacity to cross anatomical barriers during the infection cycle in mosquitoes, thus reducing the virus transmission rate. Our findings show how selective pressures act on CHIKV noncoding regions to select variants with shorter EIPs that are preferentially transmitted by the mosquito vector.
In Vivo
Emergence of a Novel Protease Inhibitor Resistance Signature in HIV-1 Matrix
Authors: Datir Rawlings , Kemp Steven , El Bouzidi Kate , Mlchocova Petra , Goldstein Richard , Breuer Judy , Towers Greg J. , Jolly Clare , Quiñones-Mateu Miguel E. , Dakum Patrick S. , Ndembi Nicaise , Gupta Ravindra K.
Published: November 2020

Protease inhibitors (PIs) are the second- and last-line therapy for the majority of HIV-infected patients worldwide. Only around 20% of individuals who fail PI regimens develop major resistance mutations in protease. We sought to explore the role of mutations in
gag
-
pro
genotypic and phenotypic changes in viruses from six Nigerian patients who failed PI-based regimens without known drug resistance-associated protease mutations in order to identify novel determinants of PI resistance.
The Nontypeable Haemophilus influenzae Major Adhesin Hia Is a Dual-Function Lectin That Binds to Human-Specific Respiratory Tract Sialic Acid Glycan Receptors
Authors: Atack John M. , Day Christopher J. , Poole Jessica , Brockman Kenneth L. , Timms Jamie R. L. , Winter Linda E. , Haselhorst Thomas , Bakaletz Lauren O. , Barenkamp Stephen J. , Jennings Michael P.
Published: November 2020

Host-adapted bacterial pathogens like NTHi have evolved specific mechanisms to colonize their restricted host niche. Relatively few of the adhesins expressed by NTHi have been characterized as regards their binding affinity at the molecular level. In this work, we show that the major NTHi adhesin Hia preferentially binds to Neu5Ac-α2-6-sialyllactosamine, the form of sialic acid expressed in humans. The receptors targeted by Hia in the human airway mirror those targeted by influenza A virus and indicates the broad importance of sialic acid glycans as receptors for microbes that colonize the human airway.
The Protein-Protein Interaction Network Reveals a Novel Role of the Signal Transduction Protein PII in the Control of c-di-GMP Homeostasis in Azospirillum brasilense
Authors: Gerhardt Edileusa C. M. , Parize Erick , Gravina Fernanda , Pontes Flávia L. D. , Santos Adrian R. S. , Araújo Gillize A. T. , Goedert Ana C. , Urbanski Alysson H. , Steffens Maria B. R. , Chubatsu Leda S. , Pedrosa Fabio O. , Souza Emanuel M. , Forchhammer Karl , Ganusova Elena , Alexandre Gladys , de Souza Gustavo A. , Huergo Luciano F.
Published: November 2020

The PII proteins sense and integrate important metabolic signals which reflect the cellular nutrition and energy status. Such extraordinary ability was capitalized by nature in such a way that the various PII proteins regulate different facets of metabolism by controlling the activity of a range of target proteins by protein-protein interactions. Here, we determined the PII protein interaction network in the plant growth-promoting nitrogen-fixing bacterium
Azospirillum brasilense
. The interactome data along with metabolome analysis suggest that PII functions as a master metabolic regulator hub. We provide evidence that PII proteins act to regulate c-di-GMP levels
in vivo
and cell motility and adherence behaviors.
Infant Skin Bacterial Communities Vary by Skin Site and Infant Age across Populations in Mexico and the United States
Authors: Manus Melissa B. , Kuthyar Sahana , Perroni-Marañón Ana Gabriela , Núñez-de la Mora Alejandra , Amato Katherine R.
Published: November 2020

This study contributes to the sparse literature on the infant skin microbiome in general, and the virtually nonexistent literature on the infant skin microbiome in a field setting. While microbiome research often addresses patterns at a national scale, this study addresses the influence of population-level factors, such as maternal socioeconomic status and contact with caregivers, on infant skin bacterial communities. This approach strengthens our understanding of how local variables influence the infant skin microbiome, and paves the way for additional studies to combine biological sample collection with questionnaires to adequately capture how specific behaviors dictate infant microbial exposures. Work in this realm has implications for infant care and health, as well as for investigating how the microbial communities of different body sites develop over time, with applications to specific health outcomes associated with the skin microbiome (e.g., immune system development or atopic dermatitis).
Lithologic, geomorphic, and permafrost controls on recent landsliding in the Alaska Range
Authors: Patton A.I. , Rathburn S.R. , Capps D. , Brown R.A. , Singleton J.S.
Published: November 2020

Because landslide regimes are likely to change in response to climate change in upcoming decades, the need for mechanistic understanding of landslide initiation and up-to-date landslide inventory data is greater than ever. We conducted surficial geologic mapping and compiled a comprehensive landslide inventory of the Denali National Park road corridor to identify geologic and geomorphic controls on landslide initiation in the Alaska Range. The supplemental geologic map refines and improves the resolution of mapping in the study area and adds emphasis on surficial units, distinguishing multiple glacial deposits, hillslope deposits, landslides, and alluvial units that were previously grouped. Results indicate that slope angle, lithology, and thawing ice-rich permafrost exert first-order controls on landslide occurrence. The majority (84%) of inventoried landslides are <0.01 km2 in area and occur most frequently on slopes with a bimodal distribution of slope angles with peaks at 18° and 28°. Of the 85 mapped landslides, a disproportionate number occurred in unconsolidated sediments and in felsic volcanic rocks. Weathering of feldspar within volcanic rocks and subsequent interactions with groundwater produced clay minerals that promote landslide initiation by impeding subsurface conductivity and reducing shear strength. Landslides also preferentially initiated within permafrost, where modeled mean decadal ground temperature is −0.2 ± 0.04 °C on average, and active layer thickness is ∼1 m. Landslides that initiated within permafrost occurred on slope angles ∼7° lower than landslides on seasonally thawed hillslopes. The bimodal distribution of slope angles indicates that there are two primary drivers of landslide failure within discontinuous permafrost zones: (1) atmospheric events (snowmelt or rainfall) that saturate the subsurface, as is commonly observed in temperate settings, and (2) shallow-angle landslides (<20° slopes) in permafrost demonstrate that permafrost and ice thaw are also important triggering mechanisms in the study region. Melting permafrost reduces substrate shear strength by lowering cohesion and friction along ice boundaries. Increased permafrost degradation associated with climate change brings heightened focus to low-angle slopes regionally as well as in high-latitude areas worldwide. Areas normally considered of low landslide potential will be more susceptible to shallow-angle landslides in the future. Our landslide inventory and analyses also suggest that landslides throughout the Alaska Range and similar climatic zones are most likely to occur where low-cohesion unconsolidated material is available or where alteration of volcanic rocks produces sufficient clay content to reduce rock and/or sediment strength. Permafrost thaw is likely to exacerbate slope instability in these materials and expand areas impacted by landslides.
Supplemental Material: Trace-element and Sr and Nd isotopic geochemistry of Cretaceous bentonites in Wyoming and South Dakota tracks magmatic processes during eastward migration of Farallon arc plutons
Authors: Hannon Jeffrey S. , al. et
Published: November 2020

Geochemical data, Sr isotope data, and Nd isotope data.
Adsorption of Algerian Asphaltenes onto Synthesized Maghemite
Iron Oxide Nanoparticles
Authors: Abbas H. , Manasrah A. D. , Saad A. Abidi , Sebakhy K. O. , Bouhadda Y.
Published: November 2020

In this study, the adsorption of Algerian asphaltene sample extracted from
Hassi Messaoud oil field is conducted for the first time. The adsorption process
was performed using novel synthesized iron oxide nanoparticles
(γ-Fe2O3).
γ-Fe2O3 Nanoparticles were
in-house synthesized and characterized by an array of techniques using,
Brunauer-Emmett-Teller (BET), high-resolution transmission electron microscopy
(HRTEM) and X-ray diffraction (XRD). The results showed that the synthesized
nanoparticles have an average crystalline domain size around 10 nm and a
specific surface area of 120 m2/g. The adsorption
process of the Algerian asphaltenes took place in a batch mode by dissolving the
asphaltenes in toluene at 25°C. Different initial concentrations of asphaltene
solutions were used in this study, namely 100, 500, and 1000 ppm. During this
adsorption, both isotherm and kinetic studies were investigated. The results
showed that the synthesized iron oxide nanoparticles are promising
nano-adsorbents that have a high affinity to remove the asphaltenes and the
equilibrium was recorded after 15 min. The Solid-Liquid-Equilibrium (SLE) model
was used to correlate the adsorption experimental data.
Coatomer-associated protein subunit alpha syndrome: abnormal trafficking between the Golgi complex and the endoplasmic reticulum
Authors: Perrin Julie , Roux Nicolas , Maurier François
Published: November 2020

A 25-year-old woman with a history of juvenile idiopathic arthritis and rheumatoid factor-positive polyarthritis developed dyspnoea. Progressive cystic lung disease was diagnosed. Biomarkers of autoimmunity, such as antinuclear antibodies, antiextractable nuclear antigen antibodies, anti-SCL-70, rheumatoid factor, cyclic citrullinated peptide antibodies, c-antineutrophil cytoplasmic antibody and MPO, were found. No familial disease was reported. Despite lack of kidney manifestations, coatomer-associated protein subunit alpha syndrome was suggested. Type 1 interferon signature score was 40.8 (range, <2.3). A class 4 heterozygous mutation (c.725T>G, p.Val242Gly) was confirmed. Due to abnormal trafficking between the Golgi complex and the endoplasmic reticulum, a Mendelian monogenic autosomal dominant syndrome associating inflammatory arthritis with interstitial lung disease, with several high-titre autoantibodies, was identified. Treatment with tyrosine kinase inhibitors, Janus kinases-signal transducers and activators of transduction, may be beneficial.
Cancer-associated retinopathy preceding the diagnosis of a pulmonary carcinoid tumour
Authors: Merle Geoffrey , Baglivo Edoardo , Younossian Alain B , Vijgen Sandrine , Karenovics Wolfram , Kherad Omar
Published: November 2020

Cancer-associated retinopathy (CAR) belongs to the paraneoplastic retinopathy syndromes and manifests itself by rapidly progressive vision loss, scotoma and photopsia. We herein reported the case of a 77-year-old woman without a cancer history who presents typical CAR symptoms. A complete workup followed by lung biopsy enabled the detection of a pulmonary carcinoid tumour. Treatment of oral cortisone was then initiated with dramatic improvements in the symptoms.
Ulnar stress reaction in an axillary crutch user
Authors: Manocha Ranita Harpreet Kaur , Weidner Jenelle
Published: November 2020

Ulnar stress fractures have been reported in athletes performing repetitive, high-impact activities, such as baseball pitchers and gymnasts. Crutch-assisted walking also results in cyclical forearm loading. We report the first case of ulnar stress reaction due to axillary crutch use. A 23-year-old right-handed woman experienced right forearm pain and imaging confirmed a right ulnar stress injury. The patient was also found to have mild hypercortisolism, low bone mass and vitamin D deficiency. Crutches were discontinued and physical therapy to normalise weight bearing through the left leg was prescribed. The patient’s right forearm symptoms resolved and she was started on oral vitamin D supplementation. Axillary crutch use may result in ulnar stress injury, particularly in vulnerable populations. The addition of an upper extremity injury to someone with impaired mobility may compound disability. As such, clinicians should be aware of the clinical presentation of ulnar stress fractures in the long-term axillary crutch user.
Fulminant immune-mediated necrotising myopathy (IMNM) mimicking myocardial infarction with non-obstructive coronary arteries (MINOCA)
Authors: Glenn-Cox Sophie , Foley Robert William , Pauling John D , Rodrigues Jonathan C L
Published: November 2020

A 74-year-old man, with inflammatory arthritis, recently commenced on adalimumab, presented with a 4-week history of left-sided chest pain, malaise and shortness of breath. Admission ECG showed age-indeterminate left bundle branch block. Troponin T was 4444 ng/L (normal range <15 ng/L) and acute coronary syndrome treatment was commenced. Catheter angiogram revealed mild-burden non-obstructive coronary disease. Cardiac magnetic resonance (CMR) was performed to refine the differential diagnosis and demonstrated no myocardial oedema or late gadolinium enhancement. Extracardiac review highlighted oedema and enhancement of the left shoulder girdle muscles consistent with acute myositis. Creatine kinase was subsequently measured and significantly elevated at 7386 IU/L (normal range 30–200 IU/L in men). Electrophoresis clarified that this was of predominantly skeletal muscle origin. Myositis protocol MRI revealed florid skeletal muscle oedema. The MR findings, together with positive anti-Scl-70 antibodies, suggested fulminant immune-mediated necrotising myopathy presenting as a rare mimic of myocardial infarction with non-obstructive coronary arteries, diagnosed by careful extracardiac CMR review.
Ovarian ectopic pregnancy after in vitro fertilisation treated by laparoscopic excision with ovarian preservation
Authors: Ribeiro Kelly , El Shamy Tarek , Miskry Tariq
Published: November 2020

A 42-year-old woman presented with lower abdominal pain and fainting episodes 36 days after in vitro fertilisation and embryo transfer. Transvaginal ultrasound revealed a large amount of free fluid in the pouch of Douglas and no evidence of an intrauterine gestational sac or adnexal mass suggestive of ectopic pregnancy. A presumed haemorrhagic corpus luteal cyst was seen in the left ovary. Laparoscopic exploration revealed a left ovarian haemorrhagic mass, which was excised with preservation of the ovary. Histopathological examination confirmed an ovarian ectopic pregnancy (OEP). OEP is rare but potentially life-threatening, as it can lead to internal haemorrhage. Its diagnosis is challenging as preoperative and intraoperative findings can be evocative of the far more frequent haemorrhagic corpus luteal cyst and histopathology is often necessary to confirm the diagnosis. Early recognition of OEP is crucial to reduce maternal morbidity and mortality, and allow treatment that preserves fertility as much as possible.
Unusual manifestation of Koch’s disease: Gradenigo-Lannois syndrome
Authors: Chandran Aswin , Sagar Prem , Monga Rabia , Singh Shuchita
Published: November 2020

Gradenigo-Lannois syndrome or petrous apicitis is an uncommon but a morbid complication of otitis media. Traditionally treated by surgery, recent advances in imaging and antibiotics have favoured a more conservative approach. Although pyogenic organisms are the leading aetiological agent, petrous apicitis due to Koch’s bacilli is not rare. We report two cases of tubercular petrositis presenting as Gradenigo’s syndrome with triad of ear discharge, deep-seated retro-orbital pain and diplopia. The first patient represented a mixed infection with pyogenic organism and tuberculosis, which was successfully treated with antibiotics and antitubercular therapy. The second patient showed an acute presentation of Gradenigo’s syndrome with chronic otitis media having contact with an active tuberculosis case and showed dramatic response with antitubercular treatment. Tubercular petrous apicitis must be suspected and diagnosed promptly as only specific treatment will lead to symptomatic resolution and avoid complications.
NovelNSDHLgene variant for congenital hemidysplasia with ichthyosiform erythroderma and limb defects (CHILD) syndrome
Authors: Maceda Ebner Bon Gatus , Kratz Lisa E , Ramos Veronica Marie E , Abacan Mary Ann R
Published: November 2020

We report a case of a 1-year and 2-month-old girl with clinical features consistent with congenital hemidysplasia with ichthyosis and limb defects syndrome. Sterol analysis from skin flakes revealed increased levels of a mono 4-alpha methyl sterol also seen in plasma as well as the presence of 4-alpha-carboxy-4-methyl-cholest-8(9)-en-3beta-ol and several keto-sterols, which are usually below the limit of detection. This sterol pattern is consistent with abnormal function of the 4-alpha-methylsterol-4-demethylase complex.NSDHLgene testing revealed the presence of a variant of uncertain significance, c.130G>A (p.Gly44Ser). This missense mutation currently is not included in population databases (ExAC no frequency) and has not been reported in individuals with anNSDHL-related condition. Parental studies showed that neither parent carries theNSDHLvariant. On this basis, this variant has been reclassified as likely pathogenic. Symptomatic treatment with keratolytic agents, emollients and ketoconazole was initiated.
Subretinal abscess as an initial presentation of systemic nocardiosis
Authors: Malik Muhammad Bilal , Ahsan Nida Jawed , Hilal Kiran , Mahmood Syed Faisal , Siddiqui M A Rehman
Published: November 2020

We report a case of subretinal abscess as the initial presentation of systemic nocardiosis. The patient was a known case of chronic inflammatory demyelinating polyneuropathy and on long-term immunosuppressants. He presented with a rapidly progressive, unilateral decline in visual acuity in the right eye. Dilated fundus examination showed a large whitish subretinal lesion. A working diagnosis of subretinal abscess was made. The appearance was highly suspicious forNocardiaabscess. On further direct questioning, it was noted that the patient had been experiencing low-grade fever and non-productive cough for 1 month. The patient was referred to infectious diseases for systemic work-up and a vitreous tap was done, along with intravitreal antibiotics. Blood culture and bronchoalveolar lavage both reportedNocardiaspecies. Sensitivity-guided antibiotic therapy resulted in improved systemic condition and a quiet and comfortable right eye, but vision could not be saved due to late presentation.
Mephentermine dependence in a young Indian adult without psychosis
Authors: Somani Aditya
Published: November 2020

Mephentermine is a vasopressor drug closely related to amphetamine and methamphetamine. Cases of abuse and dependence to mephentermine have dotted medical literature for a long time. Till date, 11 cases of dependence to mephentermine have been published. In this report, a case of mephentermine dependence is being discussed. The patient was a young adult male who was dependent to mephentermine for nearly 3 years. He was an athlete and was introduced to mephentermine by his peer for enhancing performance. He did not develop any major physical or psychiatric issue due to the drug. He was managed on out patient basis. Though cases of mephentermine dependence are few and far in medical literature, reports from other sources indicate that the problem could be more common and could be on rise. High index of suspicion and holistic care is likely to help patients and treating clinicians.
Surfactant therapy to facilitate weaning in paediatric patients dependent on extacorporeal membrane oxygenation
Authors: Achanta Nikhil , Vujcikova Julia , Nichani Sahil , Nichani Sanjiv
Published: November 2020

We are reporting two paediatric cases with severe adenoviral acute respiratory distress syndrome with viral counts of 308 and 119 million copies/mL respectively, who required venoarterial extracorporeal membrane oxygenation (ECMO) support for nearly 3 weeks. They were static on ECMO and had shown a complete lack of response to all therapeutic interventions aimed at decreasing ECMO support. To facilitate weaning from ECMO, they received 2–3 doses of surfactant. This led to dramatic improvement in pulmonary compliance, oxygenation and chest X-ray. They were both weaned off ECMO within 24 hours of receiving surfactant. Surfactant was well tolerated, with no adverse effects. In both cases, weaning from ECMO was possible only after surfactant administration. From our experience, we conclude that surfactant administration is a potentially safe and effective treatment modality that helps weaning from ECMO and should be considered in patients who are dependent on ECMO for long duration.
Probable neurosarcoidosis presenting as acute on chronic otorrhoea: a difficult diagnosis
Authors: Somani Shaan N , Schneider Alexander L , Welch Kevin C , Alexiev Borislav A , Matsuoka Akihiro J
Published: November 2020

An elderly African American woman presented to our clinic following 9 months of right-sided unilateral headache, otorrhoea and progressive hearing loss. Despite treatment with topical and oral antibiotics, her clinical condition worsened, and imaging showed mastoid coalescence with an associated subgaleal abscess. She underwent right mastoidectomy and was discharged 3 days later on broad-spectrum intravenous antibiotics despite negative operative cultures. Six weeks later, she was hospitalised with diplopia secondary to a right lateral rectus palsy. Imaging showed abscess resolution but progressive bony remodelling and enhancement of the lateral extending into anterior skull base. Chest CT demonstrated upper lobe predominant pulmonary micronodules, and mastoid biopsy on revision surgery was notable for non-caseating granulomas. Further extensive work-up could not identify an alternative cause, and a presumptive diagnosis of neurosarcoidosis was made. The patient was initiated on intravenous steroids, experienced symptomatic improvement and was thereafter transitioned to oral steroid taper on discharge.
Treatment of tongue telangiectasia in a patient with hereditary haemorrhagic telangiectasia
Authors: Bowers Eve Mandisa Rader , Lee Stella
Published: November 2020

A 61-year-old Caucasian woman presented to an outpatient otolaryngology clinic with increased bleeding from a dorsal tongue telangiectasia for 3 weeks. Her history was significant for hereditary haemorrhagic telangiectasia (HHT), a rare condition that causes vascular dysplasia, and recent symptomatic anaemia requiring blood transfusions. After failing medical management with topical haemostatic agents, she was offered and underwent surgical intervention to remove the tongue telangiectasia with duel therapy potassium titanyl phosphate (KTP) laser coblation and bevacizumab injections. A team of otolaryngologists removed the lesion without complications, and the patient denied bleeding, had minimal pain, and endorsed increased quality of life postoperatively. Tongue telangiectasias can cause life-threatening bleeding in some patients with HHT, and no surgical management guidelines exist to treat them. This case demonstrates the efficacy of KTP laser followed by bevacizumab injections in treating tongue telangiectasias in a patient with HHT.
A NOAA Fisheries science perspective on the conditions during and after COVID-19: challenges, observations, and some possible solutions, or why the future is upon us
Authors: Link Jason S. , Werner Francisco E. , Werner Kevin , Walter John , Strom Mark , Seki Michael P. , Schwing Franklin , Rusin Jeremy , Porch Clay E. , Osgood Kenric , Moline Karl , Methot Richard D. , Lynch Patrick D. , Lipton Douglas , Koch Kristen , Howell Evan A. , Hare Jonathan A. , Foy Robert J. , Detlor David , Desfosse Lisa , Crofts John , Cabana Nicole
Published: November 2020

Many fisheries and marine science organizations are working to determine how to meet their missions in the midst of the COVID-19 outbreak. As such, it seems prudent to exchange ideas, share knowledge, and initiate a discussion among us. As the scientific leadership team for NOAA Fisheries, we wanted to offer some perspectives. Others are also evaluating the impacts of COVID-19 but from the perspective of addressing tactical, day-to-day concerns of restarting operations for various marine and fisheries-oriented organizations. Thus, it seemed appropriate to us to explore the potential challenges posed by COVID-19 and to purposefully ascertain whether there are strategic opportunities for improving how we conduct our operations. We need to find ways to mitigate the effects of COVID-19 on our mission and also to glean information from our responses while in the midst of the crisis. We offer some recommendations to that end and offer these thoughts not as having solved every problem, but to learn from each other, compare across organizations, and engage in dialogue within our discipline to advance much-needed changes.
A green sulfur bacterium from epsomitic Hot Lake, Washington, USA
Authors: Madigan Michael T. , Kempher Megan L. , Bender Kelly S. , Jung Deborah O. , Sattley W. Matthew , Lindemann Stephen R. , Konopka Allan E. , Dohnalkova Alice C. , Fredrickson James K.
Published: November 2020

Hot Lake is a small heliothermal and hypersaline lake in far north–central Washington State (USA) and is limnologically unusual because MgSO4 rather than NaCl is the dominant salt. In late summer, the Hot Lake metalimnion becomes distinctly green from blooms of planktonic phototrophs. In a study undertaken over 60 years ago, these blooms were predicted to include green sulfur bacteria, but no cultures were obtained. We sampled Hot Lake and established enrichment cultures for phototrophic sulfur bacteria in MgSO4-rich sulfidic media. Most enrichments turned green or red within 2 weeks, and from green-colored enrichments, pure cultures of a lobed green sulfur bacterium (phylum Chlorobi) were isolated. Phylogenetic analyses showed the organism to be a species of the prosthecate green sulfur bacterium Prosthecochloris. Cultures of this Hot Lake phototroph were halophilic and tolerated high levels of sulfide and MgSO4. In addition, unlike all recognized species of Prosthecochloris, the Hot Lake isolates grew at temperatures up to 45 °C, indicating an adaptation to the warm summer temperatures of the lake. Photoautotrophy by Hot Lake green sulfur bacteria may contribute dissolved organic matter to anoxic zones of the lake, and their diazotrophic capacity may provide a key source of bioavailable nitrogen, as well.
Revealing neutrino nature and CPT violation with decoherence effects
Authors: Buoninfante Luca , Capolupo Antonio , Giampaolo Salvatore M. , Lambiase Gaetano
Published: November 2020

We study decoherence effects on mixing among three generations of neutrinos. We show that in presence of a non-diagonal dissipation matrix, both Dirac and Majorana neutrinos can violate the CPT symmetry and the oscillation formulae depend on the parametrization of the mixing matrix. We reveal the CP violation in the transitions preserving the flavor, for a certain form of the dissipator. In particular, for such dissipators, the CP violation affects all the transitions in the case of Majorana neutrinos, unlike Dirac neutrinos which still preserve the CP symmetry in one of the transitions flavor preserving. The precise form of the dissipation matrix is not known a-priori as it depends on the nature of the phenomenon that originates it. However, our theoretical results show that decoherence effects, if exist for neutrinos, could allow to reveal the neutrino nature and to test fundamental symmetries.
Thermal noise study of a radiation pressure noise limited optical cavity with fused silica mirror suspensions
Authors: Di Pace Sibilla , Naticchioni Luca , De Laurentis Martina , Travasso Flavio
Published: November 2020

In this work we study the thermal noise of two monolithically suspended mirrors in a tabletop high-finesse optical cavity. We show that, given suitable seismic filters, such a cavity can be designed to be sensitive to quantum radiation pressure fluctuations in the audio band of gravitational wave interferometric detectors below 1 kHz. Indeed, the thermal noise of the suspensions and of the coatings constitutes the main limit to the observation of quantum radiation pressure fluctuations. This limit can be overcome with an adequate choice of mirror suspension and coating parameters. Finally, we propose to combine two optical cavities, like those modeled in this work, to obtain a tabletop quantum radiation pressure-limited interferometer.

Graphical abstract
The geometry, branes and applications of exceptional field theory
Authors: Berman David S. , Blair Chris
Published: November 2020

This is a review of exceptional field theory: a generalisation of Kaluza–Klein theory that unifies the metric and [Formula: see text]-form gauge field degrees of freedom of supergravity into a generalised or extended geometry, whose additional coordinates may be viewed as conjugate to brane winding modes. This unifies the maximal supergravities, treating their previously hidden exceptional Lie symmetries as a fundamental geometric symmetry. Duality orbits of solutions simplify into single objects, that in many cases have simple geometric interpretations, for instance as wave or monopole-type solutions. It also provides a route to explore exotic or nongeometric aspects of M-theory, such as exotic branes, [Formula: see text]-folds, and more novel sorts of non-Riemannian spaces.
Large star/rose extra dimension with small leaves/petals
Authors: Nortier Florian
Published: November 2020

In this paper, we propose to compactify a single Large Extra Dimension (LED) on a star/rose graph with a large number of identical leaves/petals. The 5D Planck scale can be chosen to be [Formula: see text] TeV which can provide a path to solve the gauge hierarchy problem. The leaf/petal length scale is of [Formula: see text], where [Formula: see text] GeV is the weak scale, without the large geometrical hierarchy of the traditional LED models to stabilize. The 4D fields of the SM are localized on a 3-brane at the central vertex of the star/rose graph. We predict a tower of feebly coupled weak scale Kaluza–Klein (KK) gravitons below a regime of strongly coupled gravitational phenomena above the TeV scale. Moreover, we reformulate in our setup the LED mechanism to generate light Dirac neutrinos, where the right-handed neutrinos are KK-modes of gauge singlet fermions propagating in the bulk. A large number of KK-gravitons and KK-neutrinos interact only gravitationally and thus constitute a hidden sector.
Research on the semiclassical theory and Hawking tunneling radiation of nonstationary Kerr black hole
Authors: Wang Tao , Wu Xinxing , Ding Qun-Chao , Yang Shu-Zheng
Published: November 2020

In this paper, the tunneling radiations of spin 1/2 and spin 3/2 fermions from the nonstationary Kerr black hole are investigated. First, according to the Dirac equation and the Rarita–Schwinger equation, the Hamilton–Jacobi equations for spin 1/2 and 3/2 fermions are derived. Then, the tunneling behavior of fermions on the event horizon of the black hole is investigated. Finally, the thermodynamic properties of the nonstationary Kerr black hole are obtained.
Constraint analysis of measurement accuracy in high-precision X-ray pulsar positioning
Authors: Yao Li , Tong Su , Mei Luan , Furui Zhang , Yechuan Zhu , Yun Du , Baosheng Zhao
Published: November 2020

In this paper, the relationship between direct measurement of X-ray pulsar angular position and second-order correlation is analyzed by classical statistical optics. On this basis, a scheme for measuring pulsar angle position is put forward on account of X-ray band intensity correlation, which is expected to achieve a positioning accuracy of 10 Mas. Finally, the connection between positioning accuracy and complex correlation in the intensity correlation measurement is studied. Also, main factors that affected the measurement are analyzed.
Giant dielectric constant and high-temperature dielectric relaxation properties in La-doped SrTiO3 ceramics
Authors: Liu Tianyang , Wang Xiaofei , Li Congcong , Shen Bowen , Yao Mingyan , Pei Xinyang , Yang Yahui , Ou Yanglei , Zhu Zhaofei , Li Liben
Published: November 2020

[Formula: see text] (SLTO) ceramics ([Formula: see text] = 0.05, 0.10, 0.15) were prepared with giant dielectric constant by the traditional solid-state method at 1350[Formula: see text]C. The temperature dependence of the dielectric constant was obtained at the temperature ranging from 29[Formula: see text]C to 500[Formula: see text]C and the frequency ranging from 2 kHz to 2 MHz. Two sets of relaxation peaks appear in the low temperature (region I) and the high temperature (region II), respectively. For region I, we conclude that the relaxation behavior is related to the oxygen vacancy migration. For region II, the two relaxation processes are caused by grain boundary for high frequency and Sr or Ti defects at grain interior for low frequency. With the doping amount reaching 0.15, the relaxation peaks disappear and become a common phase transition because of the aggravation of lattice distortion. These possible physical mechanisms of two sets of relaxation peaks are briefly discussed.
Combined experimental and computational investigation of the effect of coating on operation characteristics of solid–liquid two-phase flow centrifugal pump
Authors: Wang Yong , Chen Jie , Xie Lei , Liu Hou-Lin , Luo Kai-Kai
Published: November 2020

The objective of this paper is to apply combined experimental and computational modeling to investigate the influence of different coating thickness on the operation characteristics of solid–liquid two-phase flow centrifugal pump. According to the characteristics of sediment flow in the Yellow River Basin, the effects of polyurethane coating thickness on the energy performance and pressure fluctuation are analyzed under the condition of solid–liquid two-phase flow and clean water. Meanwhile, the internal flow characteristics and radial force of the coated pump under the condition of solid–liquid two-phase flow are studied. The results show that the blade inlet and outlet of impeller are easy to wear, and the pressure fluctuation at the outlet of the model pump can be reduced by spraying proper coating thickness. The model pump with coating increases the low-speed zone of internal flow, which is mainly due to the increase of the viscous bottom layer area. The variation amplitude of radial force in sediment-laden water decreases with the increase of coating thickness.
Properties of rotating neutron star in density-dependent relativistic mean-field models
Authors: Riahi Rashid , Kalantari Seyed Zafarollah
Published: November 2020

Equilibrium sequences were developed for rotating neutron stars in the relativistic mean-field interaction framework using four density-dependent equations of state (EOSs) for the neutron star matter. These sequences were constructed for the observed rotation frequencies of 25, 317, 346, 716 and 1122[Formula: see text]Hz. The bounds of sequences, the secular axisymmetric instability, static and Keplerian sequences were calculated in each model to determine the stability region. The gravitational mass, quadrupole moment, polar, forward and backward redshifts, and Kerr parameter were calculated according to this stability region, and the allowable range of these quantities was then determined for each model. According to the results, DDF and DD-ME[Formula: see text] were unable to properly describe the low-frequency neutron stars, PSR J0348+432, PSR J1614-2230 and PSR J0740+6620 rotate at a frequency of 25, 317 and 346[Formula: see text]Hz, respectively. On the other hand, all the selected EOSs properly described the rotation of PSR J1748-244ad and PSR J1739-285 at a frequency of 716 and 1122[Formula: see text]Hz, respectively. The mass of these stars was, therefore, in the range of [Formula: see text] and [Formula: see text], respectively. The polar, forward and backward redshifts, and the quadrupole moment were calculated in all the selected rotating frequencies and the Keplerian sequence. The results were consistent with observations. Confirming the mass of [Formula: see text] for EXO 0748-676, our result, [Formula: see text], will be close to the observed value, and the EOSs used in this study properly describe this star. Interestingly, the extremum of Kerr parameter, polar, forward and backward redshifts in all models reached constant values of, [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text], respectively. These behaviors of redshifts and Kerr parameter are approximately independent of EOS. The observed behaviors must evaluate by other EOSs to find universal relations for these quantities. Also, a limit value was found for each of these parameters. In this case where these parameters are greater than the limit value, the star can rotate at a frequency equal to or greater than [Formula: see text][Formula: see text]Hz.
A Content-Based Approach to Profile Expansion
Authors: Fernández Diego , Formoso Vreixo , Cacheda Fidel , Carneiro Victor
Published: November 2020

Collaborative Filtering algorithms suffer from the so-called cold-start problem. In particular, when a user has rated few items, recommendations offered by these algorithms are not too accurate. Profile Expansion techniques have been described as a way to tackle this problem without bothering the user with additional information requests by increasing automatically the size of the user profile. Up to now, only collaborative approaches had been proposed for Profile Expansion. However, content-based techniques can also be used. We perform a manual analysis of a movie dataset to analyze how content features behave. According to this analysis, we propose a content-based approach, which is also combined with collaborative information. Concretely, we expose the advantages and disadvantages of the combination with a popularity feature. Moreover, a comparison to pure collaborative approaches is performed. Our approach is evaluated in a new system situation. That is, not only the active user has few ratings, but also most of the users. The results show that content-based information is useful for rating prediction. In addition, recommendations are less personalized as popularity feature acquires more relevance for item selection.
Multi-Criteria Decision Making Analysis Based on Target-Oriented OWA Operator
Authors: Xia Meimei
Published: November 2020

The target-oriented multi-criteria decision making is investigated based on the ordered weighted averaging (OWA) operator. The criteria evaluations are measured by using the likelihood of satisfying the targets of criteria. To aggregate the target-oriented criteria evaluations, the target-oriented OWA operator is firstly introduced, in which the target-oriented criteria evaluations are reordered and then aggregated by using the weight vector associated with the position of criteria evaluations. Four types of targets about criteria evaluations and four types of attitudinal characters about criteria weight vector are introduced, based on which, models are given to identify the potential best alternative(s), and estimate the ranges of attitudinal characters about criteria weight vector for each potential best alternative. The proposed models can not only analyze the sensitivity of each potential best alternative, but also can explore the impact of targets about criteria evaluations and attitudinal characters about criteria weight vector on the decision results. Models are further established to find the best and worst ranking orders of each alternative based on targets about criteria evaluations, and give decision analysis by considering specific ranking orders of alternatives. The proposed method considers the targets about criteria evaluations and attitudinal character about criteria weight vector at the same time and can provide decision makers more choices. Several examples are given to illustrate the proposed methods.
On the Core, Bargaining Set and the Set of Competitive Allocations of Fuzzy Exchange Economy with a Continuum of Agents
Authors: Zhang Xia , Sun Hao , Esangbedo Moses Olabhele
Published: November 2020

In this paper, we present a new model closer to the real-life — called the fuzzy exchange economy with a continuum of agents (FXE-CA) — that combines fuzzy consumption and fuzzy initial endowment with the agent’s fuzzy preference in the fuzzy consumption set. To characterize the fuzzy competitive allocations of the FXE-CA, we define the indifference fuzzy core of a FXE-CA as the set of all fuzzy allocations that cannot be dominated by any coalition of agents. We also propose the Mas-Colell indifference fuzzy bargaining set, in which no coalition has a justified objection at a fuzzy allocation against any other coalition. Finally, we verify that the indifference fuzzy core and the indifference fuzzy bargaining set of a FXE-CA coincide with the set of all fuzzy competitive allocations under some conditions, respectively. This indicates that the agents unanimously distribute the fuzzy competitive allocations of a FXE-CA.
BOUNDS ON MULTI-ASSET DERIVATIVES VIA NEURAL NETWORKS
Authors: DE GENNARO AQUINO LUCA , BERNARD CAROLE
Published: November 2020

Using neural networks, we compute bounds on the prices of multi-asset derivatives given information on prices of related payoffs. As a main example, we focus on European basket options and include information on the prices of other similar options, such as spread options and/or basket options on subindices. We show that, in most cases, adding further constraints gives rise to bounds that are considerably tighter. Our approach follows the literature on constrained optimal transport and, in particular, builds on the work of Eckstein & Kupper (2018) [Computation of optimal transport and related hedging problems via penalization and neural networks, Appl. Math. Optimiz. 1–29].
A PILOT STUDY OF MECHANOMYOGRAPHY-BASED HAND MOVEMENTS RECOGNITION EMPHASIZING ON THE INFLUENCE OF FABRICS BETWEEN SENSOR AND SKIN
Authors: ZHANG YUE , CAO GANGSHENG , ZHAO TONGTONG , ZHANG HANYANG , ZHANG JUNTIAN , XIA CHUNMING
Published: November 2020

Multi-channel mechanomyography (MMG) signals were acquired from the forearm when the subjects were performing eight classes of hand movements related to rehabilitation training. Ten time domain (TD) features and wavelet packet node energy (WPNE) features were extracted from each channel of MMG, and the hand movements were classified by support vector machine (SVM), extreme learning machine (ELM), linear discriminant analysis (LDA) and [Formula: see text]-nearest neighborhood (KNN) and the classifying results of three methods of collecting MMG (sensors directly on skin, sensors on cotton fabric and sensors on acrylic fiber) were compared. When all TD features were selected and SVM was adopted as the classifier, the total recognition rates of hand movements were 94.0%, 93.9% and 93.6%, respectively, of three collection methods. Using ELM can obtain similar results as SVM, with the recognition rates of 94.3%, 94.3% and 94.1%, respectively, better than using LDA (88.5%, 88.6% and 88.0%) or KNN (88.9%, 89.4% and 89.0%). For each algorithm, using TD features can acquire the highest recognition rates. Once the feature set and the classifier were selected, the total recognition rates were almost equally among three collection methods (especially for some feature sets, the differences are smaller than 1%). The results confirmed that satisfactory effects could be acquired even when the MMG was collected from sensors on fabrics with specific material, thus indicating that MMG has a unique potential value for developing wearable devices.
Genetic algorithm applied to simultaneous parameter estimation in bacterial growth
Authors: Pedrozo Hector A. , Dallagnol Andrea M. , Schvezov Carlos E.
Published: November 2020

Several mathematical models have been developed to understand the interactions of microorganisms in foods and predict their growth. The resulting model equations for the growth of interacting cells include several parameters that must be determined for the specific conditions to be modeled. In this study, these parameters were determined by using inverse engineering and a multi-objective optimization procedure that allows fitting more than one experimental growth curve simultaneously. A genetic algorithm was applied to obtain the best parameter values of a model that permit the construction of the front of Pareto with 50 individuals or phenotypes. The method was applied to three experimental data sets of simultaneous growth of lactic acid bacteria (LAB) and Listeria monocytogenes (LM). Then, the proposed method was compared with a conventional mono-objective sequential fit. We concluded that the multi-objective fit by the genetic algorithm gives superior results with more parameter identifiability than the conventional sequential approach.
Solitons of Kählerian space-time manifolds
Authors: Praveena M. M. , Bagewadi C. S. , Krishnamurthy M. R.
Published: November 2020

We study solitons of almost pseudo symmetric Kählerian space-time manifold. It is considered that different curvature tensors like projective, conharmonic and conformal curvature tensors in almost pseudo symmetric Kählerian space-time manifolds are flat. It is shown that solitons are steady, expanding or shrinking under different relations of isotropic pressure, the cosmological constant, energy density and gravitational constant.