bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlling acoustic orbital angular momentum with artificial structures: From physics to application
Authors: Wang Wei , Liu Jingjing , Liang Bin , Cheng Jianchun
Published: June 2022

Acoustic orbital angular momentum (OAM) associated with helicoidal wavefront recently attracts rapidly-growing attentions, offering a new degree of freedom for acoustic manipulation. Due to the unique dynamical behavior and inherent mode orthogonality of acoustic OAM, its harnessing is of fundamental interests for wave physics, with great potential in a plethora of applications. The recent advance in materials physics further boosts efforts into controlling OAM-carrying acoustic vortices, especially acoustic metasurfaces with planar profile and subwavelength thickness. Thanks to their unconventional acoustic properties beyond attainable in the nature, acoustic artificial structures provide a powerful platform for new research paradigm for efficient generation and diverse manipulation of OAM in ways not possible before, enabling novel applications in diverse scenarios ranging from underwater communication to object manipulation. In this article, we present a comprehensive view of this emerging field by delineating the fundamental physics of OAM–metasurface interaction and recent advances in the generation, manipulation, and application of acoustic OAM based on artificial structures, followed by an outlook for promising future directions and potential practical applications.
The Distribution of UV Radiation Field in the Molecular Clouds of Gould Belt
Authors: Xia Jifeng , Tang Ningyu , Zhi Qijun , Jiao Sihan , Xie Jinjin , Fuller Gary A. , Goldsmith Paul F. , Li Di
Published: June 2022

The distribution of ultraviolet (UV) radiation field provides critical constraints on the physical environments of molecular clouds. Within 1 kpc of our solar system and fostering protostars of different masses, the giant molecular clouds in the Gould Belt present an excellent opportunity to resolve the UV field structure in star-forming regions. We performed spectral energy distribution (SED) fitting of the archival data from the Herschel Gould Belt Survey (HGBS). Dust radiative transfer analysis with the DUSTY code was applied to 23 regions in 14 molecular complexes of the Gould Belt, resulting in the spatial distribution of the radiation field in these regions. For 10 of 15 regions with independent measurements of star formation rate, their star formation rate and UV radiation intensity largely conform to a linear correlation found in previous studies.
Solar Flare Forecast Model Based on Resampling and Fusion Method
Authors: Wan Jie , Fu Jun-Feng , Tan Dai-Min , Han Ke , Yu Meng-Yao , E Peng
Published: June 2022

Predicting the activity of solar flares is of great significance for studying its physical mechanism and the impact on human production and life. Problems such as class imbalance, high time-series sensitivity, and over-localization of important features exist in the sample data used for flare forecasting. We design a solar flare fusion method based on resampling and the CNN-GRU algorithm to try to solve the above problems. In order to verify the effectiveness of this fusion method, first, we compared the forecast performance of different resampling methods by keeping the forecast model unchanged. Then, we used the resampling algorithm with high performance to combine some single forecast models and fusion forecast models respectively. We use the 2010–2017 sunspot data set to train and test the performance of the flare model in predicting flare events in the next 48 h. Through the conclusion of the above steps, we prove that the resampling method SMOTE and its variant SMOTE-ENN are more advantageous in class imbalance problem of flare samples. In addition, after the fusion of one-dimensional convolution and recurrent network with “forget-gate” , combined with the SMOTE-ENN to achieve TSS = 61%, HSS = 61%, TPRate = 77% and TNRate = 83%. This proves that the fusion model based on resampling and the CNN-GRU algorithm is more suitable for solar flare forecasting.
A robotic leg inspired from an insect leg
Authors: Tran-Ngoc P Thanh , Lim Leslie Ziqi , Gan Jia Hui , Wang Hong , Vo-Doan T Thang , Sato Hirotaka
Published: June 2022

While most insect-inspired robots come with a simple tarsus, such as a hemispherical foot tip, insect legs have complex tarsal structures and claws, which enable them to walk on complex terrain. Their sharp claws can smoothly attach and detach on plant surfaces by actuating a single muscle. Thus, installing an insect-inspired tarsus on legged robots would improve their locomotion on complex terrain. This paper shows that the tendon-driven ball–socket structure provides the tarsus with both flexibility and rigidity, which is necessary for the beetle to walk on a complex substrate such as a mesh surface. Disabling the tarsus’ rigidity by removing the socket and elastic membrane of a tarsal joint, means that the claws could not attach to the mesh securely. Meanwhile, the beetle struggled to draw the claws out of the substrate when we turned the tarsus rigid by tubing. We then developed a cable-driven bio-inspired tarsus structure to validate the function of the tarsus as well as to show its potential application in the legged robot. With the tarsus, the robotic leg was able to attach and retract smoothly from the mesh substrate when performing a walking cycle.
Partial coherence and amplified internal energy when thermal radiation is sourced within matter
Authors: Smith G B , Gentle A R , Arnold M D
Published: June 2022

Photons excited into ground state modes at finite temperature display partitioning among photon phases, lifetimes and distances travelled since creation. These distributions set the distance from an interface a created photon has some chance of emission. Excited photons have phase velocity set by their mode’s propagation index n which sets mode density then internal energy contribution. All photons that strike an interface obliquely if emitted are refracted, and their exit intensities are irreversible except when weak internal attenuation occurs. Attenuation index k near zero degrees is small, so reversibility is approximate. As temperature rises refraction of exiting photons varies. Total emission remains reversible after transitioning through a nonequilibrium state with no other heat inputs. In equilibrium the densities of excitations that create and annihilate photons are in balance with photon densities, and emissivity dependent on n, k, temperature, and internal incident direction. Exit intensities from pure water and crystalline silica are modelled. They contain strong resonant intensities, and match data accurately. Intrinsic resonances formed within liquids and compounds are due to photon modes hybridising with localized excitations, including molecular oscillations and the anharmonic component of lattice distortions. They explain the many resonant spectral intensities seen in remote sensing. Each hybrid oscillator is a photonic virtual bound state whose energy fluctuates between levels separated by hf. Other features addressed are radiance when solid angle changes at exit, anomalous refraction, thermal recycling of internally reflected photons, fluxes within multilayers, and enhanced internal heat flux from phonon drag by photon density gradients under an external temperature gradient.
The physical significance of imaginary phonon modes in crystals
Authors: Pallikara Ioanna , Kayastha Prakriti , Skelton Jonathan M , Whalley Lucy D
Published: June 2022

The lattice vibrations (phonon modes) of crystals underpin a large number of material properties. The harmonic phonon spectrum of a solid is the simplest description of its structural dynamics and can be straightforwardly derived from the Hellman–Feynman forces obtained in a ground-state electronic structure calculation. The presence of imaginary harmonic modes in the spectrum indicates that a structure is not a local minimum on the structural potential-energy surface and is instead a saddle point or a hilltop, for example. This can in turn yield important insight into the fundamental nature and physical properties of a material. In this review article, we discuss the physical significance of imaginary harmonic modes and distinguish between cases where imaginary modes are indicative of such phenomena, and those where they reflect technical problems in the calculations. We outline basic approaches for exploring and renormalising imaginary modes, and demonstrate their utility through a set of three case studies in the materials sciences.
Green’s function methods for excited states and x-ray spectra of functional materials
Authors: Kas J J , Vila F D , Tan Tun S , Rehr J J
Published: June 2022

Many interesting properties of functional materials, such as dynamic response and thermodynamic behavior, depend on their excited state properties. These functional properties are often related to excitations in the system, such as phonons and plasmons, which lead to inelastic losses, lifetime, and other dynamic effects. The excitations are pure many-body correlation effects that are missing from independent particle theories. They are revealed in x-ray spectra such as photoemission and absorption, where they show up as satellites beyond the quasi-particle approximation. Our main focus in this work is the use of Green’s function methods to describe these effects. In particular, we discuss how the cumulant Green’s function provides a unified treatment of such dynamic correlation effects in many contexts. Besides a robust theoretical framework, these methods also yield widely applicable tools for practical calculations of many functional properties of materials. This methodology is illustrated with a number of applications ranging from optical and x-ray spectra to thermodynamic properties, and dynamic response. Some recent extensions for more correlated systems are also briefly discussed.
Impact of technology-assisted versus manual sterile compounding on safety and efficiency in a Canadian community hospital
Authors: Fan Mark , Yang Danny , Ng Becky , Jackson Jocelyn , Bouris Katherine , Eng Sharon , Rolko Edith , Trbovich Patricia
Published: June 2022

Purpose

Interventions to improve the safety and efficiency of manual sterile compounding are needed. This study evaluated the impact of a technology-assisted workflow system (TAWS) on sterile compounding safety (checks, traceability, and error detection), and efficiency (task time).

Methods

Observations were conducted in an oncology pharmacy transitioning from a manual to a TAWS process for sterile compounding. Process maps were generated to compare manual and TAWS checks and traceability. The numbers and types of errors detected were collected, and task times were observed directly or via TAWS data logs.

Results

Analysis of safety outcomes showed that, depending on preparation type, 3 to 4 product checks occurred in the manual process, compared to 6 to 10 checks with TAWS use. TAWS checks (barcoding and gravimetric verification) produced better traceability (documentation). The rate of incorrect-drug errors decreased with technology-assisted compounding (from 0.4% [5 of 1,350 preparations] with the manual process to 0% [0 of 1,565 preparations] with TAWS use; P < 0.02). The TAWS increased detection of (1) errors in the amount of drug withdrawn from vials (manual vs TAWS, 0.4% [5/1,350] vs 1.2% [18/1565]; P < 0.02), and (2) errors in the amount of drug injected into the final container (manual vs TAWS, 0% [0/1,236] vs 0.9% [11/1,272]; P < 0.002). With regard to efficiency outcomes, TAWS use increased the mean mixing time (manual vs TAWS, 275 seconds vs 355 seconds; P < 0.001), had no significant impact on average visual checking time (manual vs TAWS, 21.4 seconds vs 21.6 seconds), and decreased average physical checking time (manual vs TAWS, 58.6 seconds vs 50.9 seconds; P < 0.001).

Conclusion

In comparison to manual sterile compounding, use of the TAWS improved safety through more frequent and rigorous checks, improved traceability (via superior documentation), and enhanced error detection. Results related to efficiency were mixed.
Do Prostaglandin Analogue Lash Lengtheners Cause Eyelid Fat and Volume Loss?
Authors: Jamison Aaron , Okafor Linda , Ullrich Katja , Schiedler Vivian , Malhotra Raman
Published: June 2022

Background

Prostaglandin analogues (PGAs; a first-line antiglaucoma treatment) have been remarketed as popular eyelash-lengthening serums due to their lash-lengthening and lash-thickening side effects. Periorbital volume loss is now a well-established side effect of topical PGAs used to treat glaucoma (prostaglandin-associated periorbitopathy) but has not, to date, been listed as a potential side effect of lash-lengthening serums containing PGAs.

Objectives

The aim of this study was to identify whether periorbital fat/volume loss is seen in users of PGA lash lengtheners.

Methods

This investigation comprised a case report and an informal randomized controlled study comparing “before-and-after” color photographs displayed on the websites of manufacturers of PGA-containing lash lengtheners (PGALLs) (ie, containing bimatoprost, norbimatoprost, isopropyl cloprostenate, dechloro-dihydroxy-difluoro-ethylcloprostenolamide, or methylamido-dihydro-noralfaprostal) vs 2 control groups: non-PGALLs (NPGALL) and false eyelashes (FLs). Expert and layperson blinded graders used a purpose-designed grading system to identify subtle signs of periorbital fat/volume loss over time.

Results

A 35-year-old female developed thin, wrinkled, darker skin, and periorbital hollowing after 10 months of treatment with Lash Boost (Rodan & Fields, San Francisco, CA), containing isopropyl cloprostenate, which reversed 6 months after discontinuation. Fifteen “before-and-after” pairs of photographs (PGALL, n = 10; NPGALL, n = 3; FL, n = 2) were graded by 5 graders (3 expert, 2 layperson). Mean grading score was 8.2 (of 19) in the PGALL group, 2.3 in the NPGALL group, and 3.2 in the FL group. PGALL scores were significantly higher than scores in the NPGALL (P < 0.001) and FL (P = 0.017) groups.

Conclusions

Review of commercial “before-and-after” photographs suggests that PGALL users develop changes compatible with prostaglandin-associated periorbitopathy. Consumers must be aware of the possibility of periorbital volume loss prior to commencing treatment with PGALLs. Often the customer-facing product ingredient list contains no mention of PGAs.

Level of Evidence: 4
Genetic determinants of individual variation in the superior temporal sulcus of chimpanzees (Pan troglodytes)
Authors: Hopkins William D , Coulon Oliver , Meguerditchian Adrien , Staes Nicky , Sherwood Chet C , Schapiro Steven J , Mangin Jean-Francois , Bradley Brenda
Published: June 2022

The superior temporal sulcus (STS) is a conserved fold that divides the middle and superior temporal gyri. In humans, there is considerable variation in the shape, folding pattern, lateralization, and depth of the STS that have been reported to be associated with social cognition and linguistic functions. We examined the role that genetic factors play on individual variation in STS morphology in chimpanzees. The surface area and depth of the STS were quantified in sample of 292 captive chimpanzees comprised of two genetically isolated population of individuals. The chimpanzees had been previously genotyped for AVPR1A and KIAA0319, two genes that play a role in social cognition and communication in humans. Single nucleotide polymorphisms in the KIAA0319 and AVPR1A genes were associated with average depth as well as asymmetries in the STS. By contrast, we found no significant effects of these KIA0319 and AVPR1A polymorphism on surface area and depth measures for the central sulcus. The overall findings indicate that genetic factors account for a small to moderate amount of variation in STS morphology in chimpanzees. These findings are discussed in the context of the role of the STS in social cognition and language in humans and their potential evolutionary origins.
The role of virome in the gastrointestinal tract and beyond
Authors: Tiamani Kawtar , Luo Shiqi , Schulz Sarah , Xue Jinling , Costa Rita , Khan Mirzaei Mohammadali , Deng Li
Published: June 2022

The human gut virome is comprised of diverse commensal and pathogenic viruses. The colonization by these viruses begins right after birth through vaginal delivery, then continues through breastfeeding, and broader environmental exposure. Their constant interaction with their bacterial hosts in the body shapes not only our microbiomes but us. In addition, these viruses interact with the immune cells, trigger a broad range of immune responses, and influence different metabolic pathways. Besides its key role in regulating the human gut homeostasis, the intestinal virome contributes to disease development in distant organs, both directly and indirectly. In this review, we will describe the changes in the gut virome through life, health, and disease, followed by discussing the interactions between the virome, the microbiome, and the human host as well as providing an overview of their contribution to gut disease and disease of distant organs.
Biology: Motion is Function
Authors: Koch Lauren Gerard , Britton Steven L
Published: June 2022

In 1966 Francis Crick declared that: “The ultimate aim of the modern movement in biology is to explain all biology in terms of physics and chemistry.” This motivated us to contemplate approaches that unify biology at a fundamental level. Exploration led us to consider the features of energy, entropy, and motion. Overall, it can be considered that motion of matter is the feature of life function. No motion. No function. In initial work we evaluated the hypothesis that the scope for biologic function is mediated mechanistically by a differential for energy transfer. Maximal treadmill running capacity served as a proxy for energy transfer. The span for capacity was estimated “biologically” by application of two-way artificial selection in rats for running capacity. Consistent with our “Energy Transfer Hypothesis” (ETH), low physical health and dysfunction segregated with low running capacity and high physical health and function segregated with high running capacity. The high energy yield of aerobic metabolism is also consonant with the ETH; that is, amongst the elements of the universe, oxygen is second only to fluorine in electronegativity. Although we deem these energy findings possibly correct, they are based on correlation and do not illuminate function via fundamental principles. For consideration of life, Entropy (2nd Law of thermodynamics) can be viewed as an open system that exchanges energy with the universe operating via nonequilibrium thermodynamics. The Principle of Maximal Entropy Production (MEP) states that: If a source of free energy is present, complex systems can intercept the free energy flow, and self-organize to enhance entropy production. The development of Benard convection cells in a water heat gradient demonstrate simplistic operation of MEP. A direct step forward would be to explain the mechanism of the obligatory motion of molecules for life function. Motion may be mediated by operation of “action at a distance” for molecules as considered by the Einstein-Podolsky-Rosen Paradox and confirmed by JS Bell. Magnetism, electricity, and gravity are also examples of action at a distance. We propose that some variant of “action at a distance” as directed by the property of Maximal Entropy Production (MEP) underwrites biologic motion.
Mitochondrial Phylogenomics of Cuscuta (Convolvulaceae) Reveals a Potentially Functional Horizontal Gene Transfer from the Host
Authors: Lin Qianshi , Banerjee Arjan , Stefanović Saša
Published: June 2022

Horizontal gene transfers (HGTs) from host or other organisms have been reported in mitochondrial genomes of parasitic plants. Genes transferred in this fashion have usually been found nonfunctional. Several examples of HGT from the mitochondrial genome of parasitic Cuscuta (Convolvulaceae) to its hosts have been reported, but not vice versa. Here we used 31 protein-coding mitochondrial genes to infer the phylogeny of Cuscuta, and compared it with previous nuclear and plastid phylogenetic estimates. We also investigated the presence of HGTs within these lineages. Unlike in plastid genomes, we did not find extensive gene loss in their mitochondrial counterparts. Our results reveal the first example of organellar HGT from host to Cuscuta. Mitochondrial atp1 genes of South African subgenus Pachystigma were inferred to be transferred from Lamiales, with high support. Moreover, the horizontally transferred atp1 gene has functionally replaced the native, vertically transmitted copy, has an intact open reading frame, and is under strong purifying selection, all of which suggests that this xenolog remains functional. The mitochondrial phylogeny of Cuscuta is generally consistent with previous plastid and nuclear phylogenies, except for the misplacement of Pachystigma when atp1 is included. This incongruence may be caused by the HGT mentioned earlier. No example of HGT was found within mitochondrial genes of three other, independently evolved parasitic lineages we sampled: Cassytha/Laurales, Krameria/Zygophyllales, and Lennooideae/Boraginales.
Rheology of partially molten plagioclase containing wetting silica-rich anhydrous melt
Authors: Dimanov Alexandre
Published: June 2022

This work explores the effects of melt chemistry on diffusion controlled creep of partially molten labradorite plagioclase (An50) at anhydrous conditions. Using sol-gel and hot pressing techniques we produced: (1) nominally melt-free samples, with <1 vol. per cent residual glass confined solely to multiple-grain junctions; (2) two types of partially molten samples, containing respectively ∼1 and ∼5 vol. per cent silica-rich partial melts, wetting numerous grain boundaries by thin (<10 nm) amorphous films. Energy dispersive X-ray analysis showed that the amorphous phases of the latter materials contained ∼85 and 95 wt. per cent SiO2, thus representing different polymerization degrees. Infrared spectroscopy showed that the initial traces of water (∼0.05 wt. per cent) were dried out by annealing in air above 1100 °C. Uniaxial creep tests performed at temperatures and flow stresses ranging, respectively, between 1100–1250 °C and 3–60 MPa showed dominantly linear viscous flow, with a strong grain size dependence indicating grain boundary diffusion control. Counter-intuitively strength and activation energy increased with the content of melts. However, for the sample suite silica content covaries with melt proportion, and thus our results suggest that the kinetics of grain boundary diffusion controlled creep strongly depends on melt chemistry. Instead of acting as shortcut for diffusion, thin films of highly viscous amorphous phases may in turn considerably hinder grain boundary transport properties.
Convergence is Only Skin Deep: Craniofacial Evolution in Electric Fishes from South America and Africa (Apteronotidae and Mormyridae)
Authors: Ford Kassandra L , Peterson Rose , Bernt Maxwell , Albert James S
Published: June 2022

Synopsis

Apteronotidae and Mormyridae are species-rich clades of weakly electric fishes from Neotropical and Afrotropical freshwaters, respectively, known for their high morphological disparity and often regarded as a classic example of convergent evolution. Here, we use CT-imaging and 3D geometric morphometrics to quantify disparity in craniofacial morphologies, and to test the hypothesis of convergent skull-shape evolution in a phylogenetic context. For this study, we examined 391 specimens representing 78 species of Apteronotidae and Mormyridae including 30 of 37 (81%) of all valid genera with the goal to sample most of the craniofacial disparity known in these clades. We found no overlap between Apteronotidae and Mormyridae in the skull-shape morphospace using PCA and a common landmark scheme, and therefore no instances of complete phenotypic convergence. Instead, we found multiple potential instances of incomplete convergence, and at least one parallel shift among electric fish clades. The greatest components of shape variance in both families are the same as observed for most vertebrate clades: heterocephaly (i.e., opposite changes in relative sizes of the snout and braincase regions of the skull), and heterorhynchy (i.e., dorsoventral changes in relative snout flexion and mouth position). Mormyrid species examined here exhibit less craniofacial disparity than do apteronotids, potentially due to constraints associated with a larger brain size, ecological constraints related to food-type availability. Patterns of craniofacial evolution in these two clades depict a complex story of phenotypic divergence and convergence in which certain superficial similarities of external morphology obscure deeper osteological and presumably developmental differences of skull form and function. Among apteronotid and mormyrid electric fishes, craniofacial convergence is only skin deep.
Physical Symptoms, Distress, and Functional Disability in Youth With Chronic Orthostatic Intolerance
Authors: Tsai Owens Michele S , Biggs Bridget K , Fahrenkamp Amy C , Geske Jennifer , Hofschulte Deanna R , Harbeck-Weber Cynthia , Fischer Philip R
Published: June 2022

Objective

Youth with chronic orthostatic intolerance (OI) can experience significant physical, social, and academic functional debilitation. Previous studies have indicated associations among symptom severity, psychosocial factors, and functional disability. However, empirically tested models explaining how different medical and psychosocial factors may contribute to functional disability are lacking. The current cross-sectional study aimed to evaluate mediation, moderation, and additive models of the effect of physical symptoms and psychological distress on functional disability.

Methods

One hundred and sixty-five youth (13–22 years old) undergoing medical evaluation of chronic OI symptoms completed measures of autonomic dysfunction symptom severity, depressive and anxiety symptoms, and functional disability. Models were evaluated using tests of indirect effects and linear and logistic regression analyses.

Results

Results supported the mediation and additive effects models for depressive symptoms. Mediation, moderation, and additive models for hypothesized effects of anxiety symptoms were not supported.

Conclusions

Results provide preliminary support for models in which OI symptoms affect functional debility via their effects on mood and in which depressive symptoms have unique and additive effects on functioning. Findings lay the foundation for longitudinal and experimental evaluation of biopsychosocial models of functional disability in youth with chronic OI and related conditions. Implications include the importance of a biopsychosocial conceptualization of OI symptoms and debility as a complex interplay of factors rather than as a purely physiological or psychological process.
#20 Bloodstream Infection is Associated with Prior Gut Microbiome Colonization of the Same Strain in the Neonatal Intensive Care Unit
Authors: Schwartz Drew
Published: June 2022

Background

Infants hospitalized in neonatal intensive care units (NICUs) have high incidence of bacterial bloodstream infections (BSIs) leading to up to 15% mortality and substantial morbidity. Common etiologies of BSI in the NICU are pathogens also capable of colonizing the preterm infant gut. However, differentiating susceptible neonates from those in the same environment remains challenging. We hypothesized that the same strains causing BSI increase in abundance in the gut of affected neonates prior to bacteremia and increased above controls in the same environment.

Method

We performed shotgun metagenomic sequencing on 462 fecal samples from 19 infants with BSI and 37 controls in the same NICUs paired for gestational age, days of life, antibiotic exposure, delivery mode, and sex. We whole genome sequenced the BSI isolate from 19 cases (6 Staphylococcus aureus, 3 Streptococcus agalactiae, 3 Serratia marcescens, 2 Enterococcus faecalis, 2 Klebsiella pneumoniae, 2 Escherichia coli, and 1 Enterobacter cloacae). We utilized MetaPhLan3 to infer taxonomy and InStrain to track the whole genome sequence of the BSI pathogen within the fecal metagenomes longitudinally. We performed generalized linear mixed effect models with MaAsLin2 to determine significant associations between the microbiome and metadata with subject as a random effect.

Results

We found no differences in gut microbiome diversity or richness between cases and controls relative to bacteremia day of life. However, infants who experience a BSI possess significantly higher median relative abundances of the causative species in their gut relative to paired controls in the 2 weeks prior to bacteremia (Figure 1A, median 21.4% IQR 0.33-52 vs. 0.4% IQR 0.23-10.5, p<0.05 Wilcoxon). 10/19 infants produced at least 1 stool before bacteremia containing an organism with 0-1 genomic substitutions from the BSI isolate, establishing isogenicity between gut residing and invasive pathogen. The coverage (abundance) of the BSI isolate increased in the stool of affected neonates in the 10 days before infection to an average maximum of 0.48/1.0 (Figure 1B, linear mixed effect model p<0.05). We observed the strongest associations between high gut microbiome abundance of E. faecalis, Klebsiella spp., E. coli, and S. marcescens in the gut microbiome of cases whose BSI was caused by that organism compared to all other samples (p<0.01).

Conclusion

We show high relative abundance of the same strain in stool prior to bacteremia in hospitalized neonates. The relative abundance of the causative species is higher in cases versus paired controls. These data suggest the potential of gut microbial surveillance and management to identify blooms of gut pathogens to limit the incidence of bacteremia.
#55 Neonatal Outcome Amongst Infants Born to Mothers with Chorioamnionitis
Authors: Chang Vivian
Published: June 2022

Background

Chorioamnionitis (CA) is an acute infection/inflammation of amnion, chorion membrane of placenta and amniotic fluid associated with maternal and neonatal morbidity and mortality. Intrauterine inflammation or infection or both (Triple I) was recommended by National Institutes of Health to help in the diagnosis of CA. There are no studies correlating maternal intrapartum fever and/or Triple I and neonatal outcomes. Objective: To explore the association between maternal intrapartum fever and/or Triple I and neonatal outcomes.

Method

This was a retrospective chart review of neonates born at Flushing Hospital Medical Center from Nov 2012 to Jan 2020 with maternal intrapartum fever and gestational age (GA) >35 wks. Maternal data extracted from EHR include age, parity, ethnicity, comorbidities (diabetes mellitus, hypertension, and obesity), mode of delivery, duration of ruptured membranes (ROM), Group B streptococcus (GBS) status, Triple I, placenta pathology, first antibiotic dose to time of delivery, time interval from fever to delivery, and highest fever (Tmax). Newborn data extracted from EHR include gender, GA, birth weight (BW), Apgar score <5 at 1 minute, need for resuscitation, hyperbilirubinemia requiring phototherapy, and cultures. Sepsis ruled in (SRI) group included neonates treated with antibiotics for ≥ 7 days and sepsis ruled out (SRO) group included neonates if antibiotics discontinued after 48 hours of negative cultures. Data were analyzed using SPSS, p<0.05 was considered significant.

Results

Of 275 charts reviewed, 49 (18%) were in SRI and 226 (82%) in SRO. SRI and SRO for maternal age, parity, ethnicity, maternal comorbidities, mode of delivery, duration of ruptured membranes, GBS status, Triple I, placenta pathology, time of first dose of antibiotic to time of delivery, and time from fever to delivery were not significant. Maternal Tmax was significantly higher in SRI group, Table 1. Neonates in SRI and SRO for gender, GA, Apgar score ≤5 at one minute, BW, and hyperbilirubinemia were not significant. Need for resuscitation was significant for SRI neonates, Table 2. No neonate was readmitted or died due to early onset sepsis.

Conclusion

In our small sample, higher maternal Tmax correlated with SRI and SRI neonates were significantly more likely to require resuscitation. No neonate in either group was readmitted or died within seven days.
#16 Chasing the Small Tail of Infectious Diseases: The Rapid, Non-invasive, Culture-independent Detection Of Rat-Bite Fever With A Plasma-based Microbial Cell-free DNA Next-generation Sequencing Test (The Karius Test)
Authors: Arun Aparna
Published: June 2022

Background

Rat-bite fever (RBF) is a rare, systemic illness caused by infection with Streptobacillus moniliformis. RBF has a case-fatality risk of 7%-10% among untreated patients. Over 200 cases of RBF have been documented in the United States, but this is likely a significant under-representation because RBF is not a reportable disease. The diagnosis of these infections can be limited by: (1) Streptobacillus moniliformis fastidious nature and difficulty to culture; (2) the nonspecific manifestations of the infections and clinical overlap with a broad differential diagnosis; and (3) the unreliability of rat exposure history. We demonstrate use of unbiased microbial cell free DNA (mcfDNA) next-generation sequencing (NGS) to overcome these diagnostic limitations.

Method

The Karius Test (KT) was developed and validated in Karius’s CLIA certified/CAP accredited lab (Redwood City, CA) to detect and interpret mcfDNA in plasma. After mcfDNA is extracted and NGS performed, mcfDNA sequences are aligned to a curated database of > 1000 organisms. McfDNA from organisms observed above background at statistical significance are reported and quantified in molecules/µL (MPM). KT detections of Streptobacillus moniliformis were reviewed from January 2017 - June 2021; clinical information was obtained with test requisition or consultation upon result reporting.

Results

KT detected 7 cases of Streptobacillus moniliformis at an average of 673 MPM (35-3078; SD 1185) with an average turnaround time of 28.5 hours (SD 8.4) from sample receipt from 6 unique institutions (Table 1). Six patients were children; all were immunocompetent. Fever and rash were the most common presentation in the majority of the cases. Five of seven patients had arthritis or osteomyelitis while the remaining two patients had arthralgia. A history of rat exposure was elicited in all cases (some after microbiological diagnosis). In all patients blood cultures were negative and mcfDNA NGS was the only means of microbiological diagnosis.

Conclusion

Unbiased plasma-based mcfDNA NGS provides a rapid, non-invasive test to diagnose diverse clinical infections by Streptobacillus moniliformis. These cases highlight the potential of the KT to effectively identify infections caused by fastidious/unculturable pathogens with non-specific clinical manifestations and broad differential diagnoses.
#57 COVID-19 related Multisystem Inflammatory Syndrome in a Neonate Presenting as Supraventricular Tachycardia. A Case Report
Authors: Hussain Wajid
Published: June 2022

Background

The increasing trend in COVID-19-associated multisystem inflammatory syndrome in children MIS-C has been reported as severe acute respiratory syndrome coronavirus 2 continues to spread worldwide. Impact of covid 19 on newborns remains uncertain, while low, but the risk of neonatal infection does exist. A study from China reported 3% of neonates had evidence of SARS-CoV-2 infection. Postnatal infection is considered through horizontal transmission, as SARS-CoV-2 testing on placenta, umbilical cord, amniotic fluid, vaginal secretions, and breast milk samples has been negative. Diagnosis of MIS-C is based on 6 criteria: pediatric age, persistence fever, raised inflammatory markers, signs of organ dysfunction, lack of an alternative diagnosis, and temporal relation to COVID-19 infection or exposure

Method

A CASE REPORT 24 days old neonate presented with fever, Reluctance to feed and Respiratory distress for 1 day. He was born to a mother G2P1 + 0 with no Co-morbid at 38 weeks gestation with APGAR scores of 8 at 1 minute and 9 at 5 minutes. Clinically he was febrile with heart rate of 270 beats per minute and respiratory rate of 70 breaths per minute. First and 2nd heart sounds were audible along with gallop rhythm. ECG showed rate of 270 & absent p wave suggestive of supraventricular tachycardia. INVESTIGATIONS His pro BNP 152772 pg/ml and trop I were significantly raised. Echocardiography was consistent with severe biventricular dysfunction and ejection fraction of 20 %. COVID antibodies were sent which were reactive. His inflammatory markers ferritin, LDH and D Dimer were strikingly raised. Two blood cultures and bio fire were negative, fulfilling the MIS-C criteria Adenosine was given twice with no improvement, IV amiodarone was added, which reverted SVT. IVIG was given.

Results

Improved echocardiographic led to extubation on day seven AND DISCHARGED

Conclusion

MIS-C in a neonate highlights the importance of considering the increasing spectrum of clinical manifestations, associated with SARS-CoV-2 infection. Further research is needed to make neonatal MISC guidelines
#74 PROGNOSTIC ROLE OF EOSINOPENIA IN CHILDHOOD SEPSIS
Authors: Rustam Nurlyanti
Published: June 2022

Background

Sepsis constitutes one of the most common causes of morbidity and mortality in children. To improve the survival of childhood sepsis, while reducing the risk of antimicrobial resistance, it is obligatory to perform disease risk stratification and risk-adapted antimicrobial treatment. Recently, procalcitonin and C-reactive protein (CRP) are widely used as markers in tertiary health facilities. Due to financial constraints, however, it is not possible to determine procalcitonin and CRP levels in the majority of health facilities in developing countries. A number of studies described that the absolute number of eosinophils decreases in the acute phase of bacterial infection.

Method

This medical record-based cross-sectional study involved children 1 – 18 years of age with the clinical suspicion of sepsis, who were admitted to Dr. Sardjito General Hospital during the period of 2017 – 2021. Children, who received immunosuppressive agents and had no complete medical record data, were excluded from this study.

Results

A total of 149 children were included in which 7.4% (11) cases with eosinopenia and 52.3% (78) cases with sepsis. Septic patients with eosinopenia had a mortality rate 33.3% less than patients without eosinopenia at 43.2%. There was no significant difference, p= 0.731. This means that there was no effect of eosinopenia on mortality. Out of 78 proven sepsis cases with microbial culture 7.69% (6) with eosinopenia and 94.73% without eosinopenia. There was not a significant difference (p = 0.880) between eosinopenia and sepsis.

Conclusion

Eosinopenia cannot be used to prognostic mortality childhood sepsis.
A rare case of small bowel arteriovenous malformation presenting as obscure gastrointestinal bleeding
Authors: Mirza Muhammad H , Nzewi Emeka
Published: June 2022

Lower gastrointestinal (GI) bleeding (LGIB) is a common surgical condition, which is frequently encountered in the emergency department. The most common origin of LGIB is from the colo-rectal region. However, in majority of cases where no apparent bleeding source is identified, small bowel is the area of concern. Here, we report an uncommon cause of small bowel bleeding that manifested as LGIB. A 63-year-old woman presented to emergency department with 2-day history of dark red rectal bleeding. The upper and lower GI endoscopy did not reveal any source of bleeding. Due to the ongoing blood loss, the hemoglobin level dropped significantly, necessitating blood transfusion. Subsequently, an emergency computed tomography mesenteric angiogram was performed, which showed extravasation of contrast into the distal ileum. She underwent a laparotomy where an arteriovenous malformation of the ileum was noticed. A limited ileal resection was performed, followed by primary anastomosis. She recovered well post-operatively with no further bleeding.
Rossby wave instabilities of protoplanetary discs with cooling
Authors: Huang Shunquan , Yu Cong
Published: June 2022

Rossby wave instabilities (RWIs) usually lead to non-axisymmetric vortices in protoplanetary discs and some observed substructures of these discs can be explained well by RWIs. We explore how the cooling influences the growth rate of unstable RWI modes in terms of the linear perturbation analysis. The cooling associated with the energy equation is treated in two different ways. The first approach that we adopt is a simple cooling law. The perturbed thermal state relaxes to the initial thermal state on a prescribed cooling time-scale. In the second approach, we treat the cooling as a thermal diffusion process. The difference in the growth rate between the adiabatic and isothermal modes becomes more pronounced for discs with smaller sound speed. For the simple cooling law, the growth rates of unstable modes monotonically decrease with the shorter cooling time-scale in barotropic discs. However, the dependence of the growth rate with the cooling time-scale becomes non-monotonic in non-baratopic discs. The RWIs might even be enhanced in non-barotropic discs during the transition from the adiabatic state to the isothermal state. When the cooling is treated as thermal diffusion, even in barotropic discs, the variation of the growth rate with thermal diffusivity becomes non-monotonic. Furthermore, a maximum growth rate may appear with an appropriate value of thermal diffusivity. The angular momentum flux is investigated to understand the angular momentum transport by RWIs with cooling.
Duplication of NRAMP3 Gene in Poplars Generated Two Homologous Transporters with Distinct Functions
Authors: Pottier Mathieu , Le Thi Van Anh , Primard-Brisset Catherine , Marion Jessica , Wolf Bianchi Michele , Victor Cindy , Déjardin Annabelle , Pilate Gilles , Thomine Sébastien
Published: June 2022

Transition metals are essential for a wealth of metabolic reactions, but their concentrations need to be tightly controlled across cells and cell compartments, as metal excess or imbalance has deleterious effects. Metal homeostasis is achieved by a combination of metal transport across membranes and metal binding to a variety of molecules. Gene duplication is a key process in evolution, as the emergence of advantageous mutations on one of the copies can confer a new function. Here, we report that the poplar genome contains two paralogues encoding NRAMP3 metal transporters localized in tandem. All Populus species analyzed had two copies of NRAMP3, whereas only one could be identified in Salix species indicating that duplication occurred when the two genera separated. Both copies are under purifying selection and encode functional transporters, as shown by expression in the yeast heterologous expression system. However, genetic complementation revealed that only one of the paralogues has retained the original function in the release of metals stored in the vacuole previously characterized in Arabidopsis thaliana. Confocal imaging showed that the other copy has acquired a distinct localization to the Trans-Golgi Network (TGN). Expression in poplar suggested that the copy of NRAMP3 localized on the TGN has a novel function in the control of cell-to-cell transport of manganese. This work provides a clear case of neofunctionalization through a change in the subcellular localization of a metal transporter as well as evidence for the involvement of the secretory pathway in the cell-to-cell transport of manganese.
A new bacterial tRNA enhances antibiotic production in Streptomyces by circumventing inefficient wobble base-pairing
Authors: Chen Ximing , Li Shuyan , Zhang Binglin , Sun Haili , Wang Jinxiu , Zhang Wei , Meng Wenbo , Chen Tuo , Dyson Paul , Liu Guangxiu
Published: June 2022

We report the discovery and functional characterization of a new bacterial tRNA species. The tRNA-Asp-AUC, from a fast-growing desert streptomycete, decodes GAU codons. In the absence of queuosine tRNA anticodon modification in streptomycetes, the new tRNA circumvents inefficient wobble base-pairing during translation. The tRNA, which is constitutively expressed, greatly enhances synthesis of 4 different antibiotics in the model mesophilic species Streptomyces coelicolor, including the product of a so-called cryptic pathway, and increases yields of medically-important antibiotics in other species. This can be rationalised due to increased expression of both pleiotropic and pathway-specific transcriptional activators of antibiotic biosynthesis whose genes generally possess one or more GAT codons; the frequency of this codon in these gene sets is significantly higher than the average for streptomycete genes. In addition, the tRNA enhances production of cobalamin, a precursor of S-adenosyl methionine, itself an essential cofactor for synthesis of many antibiotics. The results establish a new paradigm of inefficient wobble base-pairing involving GAU codons as an evolved strategy to regulate gene expression and, in particular, antibiotic biosynthesis. Circumventing this by expression of the new cognate tRNA offers a generic strategy to increase antibiotic yields and to expand the repertoire of much-needed new bioactive metabolites produced by these valuable bacteria.
Non-invasive metabolic profiling of inflammation in joints and entheses by multispectral optoacoustic tomography
Authors: Tascilar Koray , Fagni Filippo , Kleyer Arnd , Bayat Sara , Heidemann Robert , Steiger Florian , Krönke Gerhard , Bohr Daniela , Ramming Andreas , Hartmann Fabian , Klett Daniel , Federle Anna , Regensburger Adrian P , Wagner Alexandra L , Knieling Ferdinand , Neurath Markus F , Schett Georg , Waldner Maximilian , Simon David
Published: June 2022

Objective

To explore the metabolic characteristics of arthritis and enthesitis using multispectral opto-acoustic tomography (MSOT), a technology using near-infrared multispectral laser to stimulate tissues and detect the emitted acoustic energy, enabling non-invasive quantification of tissue components in vivo based on differential absorbance at multiple wavelengths.

Methods

We performed a cross-sectional study in patients with RA or PsA and healthy controls (HCs). Participants underwent clinical, ultrasonographic and MSOT examination of MCP and wrist joints as well as the entheses of the common extensor tendon at the lateral humeral epicondyles and of the patellar, quadriceps and Achilles tendon. MSOT-measured haemoglobin (Hb), oxygen saturation, collagen and lipid levels were quantified and scaled mean differences between affected and unaffected joints and entheses were calculated as defined by clinical examination or ultrasonography using linear mixed effects models.

Results

We obtained 1535 MSOT and 982 ultrasonography scans from 87 participants (34 PsA, 17 RA, 36 HCs). Entheseal tenderness was not associated with significant metabolic changes, whereas enthesitis-related sonographic changes were associated with increased total Hb, oxygen saturation and collagen content. In contrast, the presence of arthritis-related clinical and sonographic findings showed increased Hb levels, reduced oxygen saturation and reduced collagen content. Synovial hypertrophy was associated with increased lipid content in the joints.

Conclusion

MSOT allows determination of distinct metabolic differences between arthritis and enthesitis in a non-invasive setting in humans in vivo.