bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlling the parametric roll of a container ship model by changing the forward velocity
Authors: Deleanu D , Dumitrache C L
Published: September 2020

Parametric roll on ships is a resonance phenomenon whose onset causes heavy roll oscillations leading to dangerous situations for the ship, the cargo and the crew. It affects both small vessels with marginal stability and large container ships if four conditions are met simultaneously: the wave length and ship length are approximately equal, the frequency of encounter wave is twice the roll natural frequency, the ship’s roll damping is low enough and the wave height exceeds a limit value characteristic to each vessel. A good start to capture the basic features of the parametric roll is to cancel the couplings between roll and the other motions of the ship and to analyse the influence of parameters on the ship stability and the appearance of large roll amplitudes by using one-degree-of-freedom model. By doing this, one realizes that, besides increasing the damping, the roll motion can be stabilized by changing the wave encounter frequency in such a way that the resonance condition is no longer fulfilled. Two parameters mainly affect the encounter frequency: the ship forward velocity and the heading angle. In the paper, we have numerically investigated the effect of increasing or decreasing the forward speed on the roll amplitudes. We followed two strategies. In the first, we allowed the speed to change with a constant acceleration (positive or negative) so that the encounter frequency has left the dangerous region of the resonance. In the second strategy, we changed the forward speed up and down around a value that generates large roll amplitudes, by using different periodic profiles such as sinusoidal, saw tooth or trapezoidal. We noticed that both control techniques generally managed to significantly reduce the roll amplitudes (with a few exceptions). At the same time, we found that very important in how the amplitudes diminish are parameters like the moment of time when the control is activated, the speed rate of change or the period and amplitude of the speed change around the average value (in the second strategy). The data used in the paper have been obtained from experiments with a container ship model in a towing tank followed by expansion to a full scale ship.
On the strength assessment of a small liquid petroleum gas carrier in oblique waves by 1D and 3D-FEM analyses
Authors: Domnisoru L
Published: September 2020

The research from this paper is focused on the strength assessment in oblique design waves of a small LPG liquid petroleum gas carrier, with maximum length of 125.6 m. As loading conditions, full cargo and ballast cases are selected. Because the LPG carrier has an unrestricted maritime navigation class, the maximum height of the oblique quasi-static wave is 12 m, in hogging and sagging conditions, with a height step of 1 m. The LPG-oblique quasistatic waves heading angle is in the range 0 – 75 (360) degrees, with step 15 degrees, where the maximum structural response is expected to occur. For the numerical analyses two classes of structural models have to be considered, equivalent 1D-beam and 3D-FEM, both extended over the whole LPG length, on both sides. The 1D model is implemented in the eigen code P_QSW for the LPG and oblique waves equilibrium parameters and sectional efforts computation, by a non-linear iterative three parameters procedure. For detailed structural analysis the LPG 3D-FEM model is used, developed by Femap/NX Nastran program. Combining the numerical results by 1D and 3D models, the safety polar diagrams, in terms of limit oblique quasi-static waves’ height, for the small LPG carrier strength assessment are obtained.
On the oscillations response prediction of a small liquid petroleum gas carrier in random oblique waves
Authors: Domnisoru L
Published: September 2020

The research from this paper is focused on the dynamic study of a small liquid petroleum gas carrier, with mono-hull shape, length of 125.6 m and maximum speed 17 knots. As loading cases, full cargo and ballast conditions are considered. The random waves are modelled on short-term by the ITTC averaged power density spectrum, with the maximum significant wave height 12 m, corresponding to unrestricted navigation cases. The oblique random waves heading angle has 0-360 degrees values. The seakeeping analysis includes the main oscillation components, heave, roll and pitch, based on eigen program DYN (OSC). The numerical analyses include the oscillation transfer functions computation and the short-term evaluation in oblique random waves, for the prediction of the most probable statistical response. For the roll oscillation component, supplementary the influence of the vertical position of the small LPG gravity centre is analysed. The seakeeping criteria are formulated in terms of admissible oscillation statistical most probable amplitudes. The short-term dynamic responses of the small LPG, assessed by the seakeeping criteria, deliver the oscillations cumulative safety polar diagrams. The predicted seakeeping response of the small LPG leads to practical results for the ship’s navigation safety limits in oblique random waves.
Numerical assessment of a very high pressure ratio centrifugal impeller
Authors: Dumitrescu O , Drăgan V , Porumbel I , Gherman B
Published: September 2020

The paper focuses on studying the influence of mesh size, numerical discretization schemes and different turbulence models on radial impeller performances. The chosen impeller is a 14:1 pressure ratio novel design for use in the TIDE pulse detonation engine architecture. In preparation for the experimental research, numerical studies were performed for five steady-state analysis and one unsteady, single passage with a fully structured solver. A grid sensitivity study was conducted over four grid resolutions, starting from a coarse to dense mesh (0.7 mil, 1.5 mil, 5 mil and 9 mil), in order to determine the influence of mesh points, numerical stability and reduce interpolation errors. Another problem in a CFD study is the selection of a proper turbulence model, thus six RANS models were investigated: k-ε, v2-f, k-ω Shear Stress Transport (both steady and unsteady), Spalart – Allmaras and an Explicit Algebraic Reynolds Stress Model. Results show that global parameters such as pressure ratio and efficiency predictions remain unchanged above 1.5 mil cells/passage, while above 5 mil cells/passage, RANS models become unstable and lead to poor convergence. The most conservative model proved to be the SST with minimalistic values for both pressure ratio and isentropic efficiency.
Modeling of friction forces in an asymmetric two-roll module
Authors: Khurramov Sh R , Abdukarimov A , Khalturaev F S , Kurbanova F Z
Published: September 2020

The study is devoted to the analysis of the patterns of friction force distribution in two-roll modules. An asymmetric two-roll module is considered, in which the rolls are located relative to the vertical with a tilt to the right, have unequal diameters and elastic coatings from the materials of different stiffness and friction coefficients, the material layer is fed with a tilt downward relative to the center line. Friction stress models and formulas for calculating neutral angles in a two-roll module under consideration are determined. Dependencies between the forces acting on the rolls and the stresses distributed under these forces are established. It was revealed that these dependences do not change with a change in the angle of supply of the material layer to the line of centers and the angle of inclination of the upper roll relative to the vertical.
Overall performances of a propeller operating near the free surface
Authors: Lungu A
Published: September 2020

The paper describes a numerical study on the effects of the interaction of the free surface with a marine propeller operating close to it, including the effects of the immersion on the cross flow. Extensive simulations using the ISIS-CFD naval hydrodynamics computational fluid dynamics solver are conducted to study the open water characteristics (POW hereafter), transient blade loads, and flow behavior around the DTMB 4119 three-bladed propeller, with comparisons to the fully submerged experimental data at two different immersions in respect to the undisturbed free-surface. Computations and experiments for the deeply submerged case show that the cross flow results in an increase of the energy spent and lower efficiency relative to the uniform inflow. Near the water surface, numerical solutions show that effects on thrust and torque increase significantly as the propeller load increases. Furthermore, the presence of the free surface breaks the symmetry resulting in highest blade force losses when the blade is near top dead center. As the propeller approaches the surface, not only the amplitude of the blade higher harmonics increases, but also the efficiency drops down.
Risk management of friction liner welding reconditioning technology change
Authors: Petrescu C , Cicic DT , Solomon Ghe
Published: September 2020

The paper presents the authors’ work in identifying the main risks that may arise if pursuing the change of the reconditioning technology through welding the friction liner of the passenger car disc brake based on the technical hazard identification, and the authors analysis and management of these risks by carrying out a risk management system. Theyr work is based on the specifications of the Commission implementing regulation (EU) No 402/2013 on the common safety method for risk evaluation and assessment (EU Regulation 402/2013) [1], which is compulsory for any technical, operational and/or organizational change in the railway field that has an impact on railway safety. Also the purpose is that the modified technology does not affect railway safety.

The friction liner from the passenger cars disc brake is a part that ensures the grip of the friction pad, which applies the braking force to the brake disc to realize the braking of the rolling stock. The new reconditioning welding technology can affect the friction liner clamping function, making it possible for the friction pad to fall from the friction liner, resulting in losing braking power on the vehicle, which leads to the occurrence of rail events, thus affecting rail safety.
Modeling a Manufacturing System by Using XML - Petri Nets Technology
Authors: Pop A , Blaga F S , Ursu M P , Bungău C , Hule V
Published: September 2020

In this paper we propose an approach of modeling and simulation of a manufacturing process based on timed colored Petri nets, by developing an application based on XML (eXtensible Markup Language) technology. The architecture of an XML file that characterizes a Petri nets includes specific attributes for positions, transitions, arcs and variable declarations and color sets. This makes it possible to modify the model from a structural point of view very easily by adding lines of code for the required colors, positions, transitions and arcs. In order to generate the default model and to customize the XML-type structure, an application was created where characteristic parameters of the manufacturing process will be introduced as well as the values of the program entry. The manufacturing system considered is the realization of the sunroof component within a company. During the simulation process, the working time will be considered as 8 hours. When product demands change, the simulated model can be modified very quickly to perform the analysis according to the new requirements. The arrangement of the entities of the production system can be reconfigured, the production process can be adjusted and the resources reallocated according to the simulation results.
The naval main engines parameters variation, due different external factors
Authors: Serbanescu I , Stan L
Published: September 2020

In this paper, we carried out a real and simulated study, regarding the naval main engines parameters variation on different external factors. The ships, was in normal operation mode, at various around the globe points, so different environmental external conditions. It is worth mentioning that such studies help us to better understand the operating processes of naval propulsion engines, under different environmental conditions. We can also draw conclusions on how to improve the operating mode of these types of engines. Such tests cannot be carried out in the factory condition, only in operation mode with the ship under way. In particular, the studied parameters of the engines were: average effective pressure, average effective power and maximum combustion pressure. As external factors that have been taken into account I mention: ambient temperature, sea water temperature, supercharger pressure. The study was conducted on two known types of naval propulsion engines. The first most common is the MAN B&W 6S35MC-MK7, in this case being a propulsion engine for a tanker. The second type of naval propulsion engine is in a reefer container ship, the engine being a Sultzer 9RND-90M. The experimental or simulated determinations carried out on board the ships, were made using the existing specific reading devices. Using data obtained by direct reading or performed countless thermal calculations for each engine. There followed the interpretation of the final data obtained, many being presented graphically. The final conclusions were followed, which led to a more efficient operation by regulating certain operating parameters, such as the temperature of the supercharger air under different atmospheric weather conditions.
Tolerance allocation using Monte Carlo simulation
Authors: Tulcan A , Banciu F V , Grozav I
Published: September 2020

Tolerance allocation is an important issue in product manufacturing, ensuring on the one hand the interchangeability of parts in an assembly and on the other hand, it has a major impact on the costs of manufacturing products and quality. This paper aim is to assign in a 2D dimensional chain with, dimensional and geometric tolerances, dimensional and angular (geometrical tolerances) values to dimensions in a variation interval in order to obtain a design required variation in dimension and angle for the closing element of that chain, using the Monte Carlo (MC) simulation. MC simulation randomly assigns values of the dimensions of the dimensional chain (DC) - for their module and angle - to their tolerance field, and then calculates the range for module and angle (R) caused at closing dimension in a sufficiently large number of cases. The ratio of the desired tolerance (Tdo) to the dimension chain closing element and the range (R) resulting from the simulation, respectively Tdo/R are calculated and compared with a value that must be greater or at least equal to an imposed value of an index dependent of the Cp - capability desired at the closing dimension. At the desired value that meets design requirements, the tolerance allocation process is completed.
Latest progress in g-C3N4 based heterojunctions for hydrogen production via photocatalytic water splitting: a mini review
Authors: Rhimi Baker , Wang Chuanyi , Bahnemann Detlef W
Published: September 2020

Graphitic carbon nitride based heterojunction photocatalysts have gained increasing attention in producing the clean energy source of hydrogen. Coupling carbon nitride (g-C3N4) with other semiconductor materials or metals as co-catalysts is considered as an effective strategy to overcome the drawbacks of g-C3N4 such as the quick recombination of photogenerated charges. In this review, the recent research advancements in the construction of g-C3N4-based heterojunctions as well as their different charge separation/transfer mechanisms will be systematically discussed, making special emphasis on the design and fabrication of type-II, Z-scheme, S-scheme and Schottky heterojunctions and their application towards H2 generation from water splitting. Finally, a summary and some crucial issues, which should be further resolved for developing advanced g-C3N4-based heterojunction photocatalysts, are presented.
CANUE: A Theoretical Model of Pain as an Antecedent for Substance Use
Authors: Ferguson Erin , Zale Emily , Ditre Joseph , Wesolowicz Danielle , Stennett Bethany , Robinson Michael , Boissoneault Jeff
Published: September 2020

Background

Pain and substance use are frequently comorbid and have been shown to exert bidirectional effects. Self-medication of pain and distress via substance use is common and can be understood via negative reinforcement, ultimately strengthening the pathway between pain to substance use over time. As such, a testable model of the potentially modifiable candidate mechanisms that underlie the pain to substance use pathway is needed.

Purpose

This review proposes a testable model of pain as an antecedent to substance use to guide future research and inform clinical practice.

Methods

An integrative review of current evidence regarding pain, substance use, and associated risk factors (i.e., negative affect, pain-related attitudes, negative urgency, and substance use outcome expectancies) was conducted.

Results

The Catastrophizing, Anxiety, Negative Urgency, and Expectancy (CANUE) model highlights modifiable risk factors for self-medicating pain with substance use, including increased negative affect and maladaptive pain-related attitudes (i.e., pain catastrophizing, pain anxiety, and fear of pain), negative urgency, and substance-related outcome expectancies for pain relief and enhanced pain coping.

Conclusions

Targeted behavioral and psychological interventions that address these factors may facilitate more adaptive pain-coping responses, thereby reducing the impacts of pain on substance use. Systematic research is needed to evaluate the validity and clinical utility of this model.
Diversity and Host Plant-Use in North AmericanPhytomyzaHolly Leafminers (Diptera: Agromyzidae): Colonization, Divergence, and Specificity in a Host-Associated Radiation
Authors: Scheffer Sonja J , Lewis Matthew L , Hébert Julie B , Jacobsen Frode
Published: September 2020

Insects that feed on plants are widely used for studies of host-plant-associated speciation due to their diversity and tractability. The value of these studies necessarily depends upon an accurate understanding of the diet of the focal insects. In North America, the 12 Phytomyza Fallén (Diptera: Agromyzidae) leafmining fly species feeding on hollies (Ilex spp. (Aquifoliaceae: Ilex)) initially appeared to be primarily a host-plant-associated radiation of largely monophagous species. However, our increased collecting efforts found that a majority of the morphospecies are oligophagous, feeding on multiple Ilex species. Patterns of host-associations suggest that colonization of new hosts followed by host-associated speciation may be an important feature of diversification. Analyses of mitochondrial COI data in three oligophagous species found evidence of host-associated genetic structure consistent with processes of host-associated divergence. However, in one of these species, evidence of geographic divergence as well as host-associated divergence was detected, illustrating complexity in factors relating to speciation and host-use evolution in this radiation of leafmining flies.
Intraperitoneal vancomycin treatment of multifocal methicillin-resistant Staphylococcus aureus osteomyelitis in a patient on peritoneal dialysis
Authors: Abid Qassim , Asmar Basim , Kim Edward , Molloy Leah , Gregory Melissa , Valentini Rudolph P
Published: September 2020

Purpose

We report the case of a 2-year-old girl with end-stage renal disease managed by peritoneal dialysis (PD) who developed methicillin-resistant staphylococcal osteomyelitis of the left shoulder and was successfully treated with intraperitoneal (IP) administration of vancomycin for 2 weeks followed by oral clindamycin therapy.

The patient was hospitalized with tactile fever and a 3-day history of worsening fussiness. Radiography of the left shoulder showed findings indicative of osteomyelitis. Vancomycin was administered via central venous line for 3 days, during which time the patient underwent PD 24 hours a day. After magnetic resonance imaging revealed proximal humeral osteomyelitis, septic arthritis of the shoulder joint, and osteomyelitis of the scapula, the patient underwent incision and drainage of the left shoulder joint. Both blood and joint drainage cultures grew methicillin-resistant Staphylococcus aureus that was sensitive to vancomycin. The patient’s central venous catheter was removed on hospital day 4; due to difficulties with peripheral i.v. access and a desire to avoid placing a peripherally inserted central venous catheter, vancomycin administration was changed to the IP route, with vancomycin added to the PD fluid. During IP treatment, serum vancomycin levels were maintained at 13.5 to 18.5 mg/L, and the calculated ratio of vancomycin area under the curve to minimum inhibitory concentration was maintained above 400. After completing a 14-day course of IP vancomycin therapy, the patient was switched to oral clindamycin, with subsequent complete resolution of osteomyelitis.

Conclusion

IP vancomycin was effective for treatment of invasive S. aureus infection in this case. This approach should be considered in patients undergoing PD for whom peripheral i.v. access options are limited and/or not preferred.
Cross-cultural neuropsychological assessment in the European Union: a Delphi expert study
Authors: Franzen Sanne , Papma Janne M , van den Berg Esther , Nielsen T Rune
Published: September 2020

Objective

The increasing ethnic diversity in the European Union (EU) calls for adaptations to neuropsychological assessment practices. The aims of this study were to examine the current state of cross-cultural neuropsychological assessment in EU-15 countries and to provide recommendations for researchers and policy makers.

Method

Twelve experts from nine EU-15 countries participated in a Delphi consensus study involving two sequential rounds of web-based questionnaires and an in-person consensus meeting. The experts individually rated Delphi topics on the basis of importance (scale 1–10). The degree of consensus was determined by assessing first and third quartiles (Q1 and Q3) and medians.

Results

Consensus outcomes showed the following priorities: (a) the development of tests (median importance rating 10, Q1-Q3: 9–10), (b) the collection of normative data (median importance rating 9, Q1-Q3: 8–10), and (c) more training, awareness, and knowledge regarding cross-cultural assessment among neuropsychologists in the EU (median importance rating 9, Q1-Q3: 8–10). Whereas memory tests were often available, tests measuring social cognition (median 9, Q1-Q3: 8–10) and language (median 9, Q1-Q3: 7–10) are particularly lacking. Recommendations were made regarding essential skills and knowledge necessary for cross-cultural neuropsychological assessment.

Conclusions

This study in a small group of experts suggests that the development and availability of cross-cultural tests and normative data should be prioritized, as well as the development and implementation of training initiatives. Furthermore, EU guidelines could be established for working with interpreters during neuropsychological assessment. Before implementing these recommendations, follow-up studies are recommended that include more minority neuropsychologists and community stakeholders.
Biological network analysis with deep learning
Authors: Muzio Giulia , O’Bray Leslie , Borgwardt Karsten
Published: September 2020

Recent advancements in experimental high-throughput technologies have expanded the availability and quantity of molecular data in biology. Given the importance of interactions in biological processes, such as the interactions between proteins or the bonds within a chemical compound, this data is often represented in the form of a biological network. The rise of this data has created a need for new computational tools to analyze networks. One major trend in the field is to use deep learning for this goal and, more specifically, to use methods that work with networks, the so-called graph neural networks (GNNs). In this article, we describe biological networks and review the principles and underlying algorithms of GNNs. We then discuss domains in bioinformatics in which graph neural networks are frequently being applied at the moment, such as protein function prediction, protein–protein interaction prediction and in silico drug discovery and development. Finally, we highlight application areas such as gene regulatory networks and disease diagnosis where deep learning is emerging as a new tool to answer classic questions like gene interaction prediction and automatic disease prediction from data.
MicrobiomeExplorer: an R package for the analysis and visualization of microbial communities
Authors: Reeder Janina , Huang Mo , Kaminker Joshua S , Paulson Joseph N
Published: September 2020

We developed the MicrobiomeExplorer R package to facilitate the analysis and visualization of microbial communities. The MicrobiomeExplorer R package allows a user to perform typical microbiome analytic workflows and visualize their results, either through the command line or an interactive Shiny application included with the package. In addition to applying common analytical workflows, the application enables automated analysis report generation.

Availability and implementation

Available at https://github.com/zoecastillo/microbiomeExplorer.

Supplementary information

Supplementary data are available at Bioinformatics online.
The Speed of Development of Adolescent Brain Age Depends on Sex and Is Genetically Determined
Authors: Brouwer Rachel M , Schutte Jelle , Janssen Ronald , Boomsma Dorret I , Hulshoff Pol Hilleke E , Schnack Hugo G
Published: September 2020

Children and adolescents show high variability in brain development. Brain age—the estimated biological age of an individual brain—can be used to index developmental stage. In a longitudinal sample of adolescents (age 9–23 years), including monozygotic and dizygotic twins and their siblings, structural magnetic resonance imaging scans (N = 673) at 3 time points were acquired. Using brain morphology data of different types and at different spatial scales, brain age predictors were trained and validated. Differences in brain age between males and females were assessed and the heritability of individual variation in brain age gaps was calculated. On average, females were ahead of males by at most 1 year, but similar aging patterns were found for both sexes. The difference between brain age and chronological age was heritable, as was the change in brain age gap over time. In conclusion, females and males show similar developmental (“aging”) patterns but, on average, females pass through this development earlier. Reliable brain age predictors may be used to detect (extreme) deviations in developmental state of the brain early, possibly indicating aberrant development as a sign of risk of neurodevelopmental disorders.
Primary Care Guidance for Persons With Human Immunodeficiency Virus: 2020 Update by the HIV Medicine Association of the Infectious Diseases Society of America
Authors: Thompson Melanie A , Horberg Michael A , Agwu Allison L , Colasanti Jonathan A , Jain Mamta K , Short William R , Singh Tulika , Aberg Judith A
Published: September 2020

Advances in antiretroviral therapy (ART) have made it possible for persons with human immunodeficiency virus (HIV) to live a near expected life span, without progressing to AIDS or transmitting HIV to sexual partners or infants. There is, therefore, increasing emphasis on maintaining health throughout the life span. To receive optimal medical care and achieve desired outcomes, persons with HIV must be consistently engaged in care and able to access uninterrupted treatment, including ART. Comprehensive evidence-based HIV primary care guidance is, therefore, more important than ever. Creating a patient-centered, stigma-free care environment is essential for care engagement. Barriers to care must be decreased at the societal, health system, clinic, and individual levels. As the population ages and noncommunicable diseases arise, providing comprehensive healthcare for persons with HIV becomes increasingly complex, including management of multiple comorbidities and the associated challenges of polypharmacy, while not neglecting HIV-related health concerns. Clinicians must address issues specific to persons of childbearing potential, including care during preconception and pregnancy, and to children, adolescents, and transgender and gender-diverse individuals. This guidance from an expert panel of the HIV Medicine Association of the Infectious Diseases Society of America updates previous 2013 primary care guidelines.
Enteropathogenic Escherichia coli Infection in Cancer and Immunosuppressed Patients
Authors: Olvera Adilene , Carter Hannah , Rajan Anubama , Carlin Lily G , Yu Xiaomin , Zeng Xi-Lei , Shelburne Samuel , Bhatti Micah , Blutt Sarah E , Shroyer Noah F , Jenq Robert , Estes Mary K , Maresso Anthony , Okhuysen Pablo C
Published: September 2020

Background

The role of enteropathogenic Escherichia coli (EPEC) as a cause of diarrhea in cancer and immunocompromised patients is controversial. Quantitation of fecal bacterial loads has been proposed as a method to differentiate colonized from truly infected patients.

Methods

We studied 77 adult cancer and immunosuppressed patients with diarrhea and EPEC identified in stools by FilmArray, 25 patients with pathogen-negative diarrhea, and 21 healthy adults without diarrhea. Stools were studied by quantitative polymerase chain reaction (qRT-PCR) for EPEC genes eaeA and lifA/efa-1 and strains characterized for virulence factors and adherence to human intestinal enteroids (HIEs).

Results

Patients with EPEC were more likely to have community-acquired diarrhea (odds ratio, 3.82 [95% confidence interval, 1.5–10.0]; P = .008) compared with pathogen-negative cases. Although EPEC was identified in 3 of 21 (14%) healthy subjects by qPCR, the bacterial burden was low compared to patients with diarrhea (≤55 vs median, 6 × 104 bacteria/mg stool; P < .001). Among EPEC patients, the bacterial burden was higher in those who were immunosuppressed (median, 6.7 × 103 vs 55 bacteria/mg; P < .001) and those with fecal lifA/ifa-1 (median, 5 × 104 vs 120 bacteria/mg; P = .015). Response to antimicrobial therapy was seen in 44 of 48 (92%) patients with EPEC as the sole pathogen. Antimicrobial resistance was common and strains exhibited distinct patterns of adherence with variable cytotoxicity when studied in HIEs. Cancer care was delayed in 13% of patients.

Conclusions

Immunosuppressed cancer patients with EPEC-associated diarrhea carry high burden of EPEC with strains that are resistant to antibiotics, exhibit novel patterns of adherence when studied in HIEs, and interfere with cancer care.
Using Prior Culture Results to Improve Initial Empiric Antibiotic Prescribing: An Evaluation of a Simple Clinical Heuristic
Authors: Elligsen Marion , Pinto Ruxandra , Leis Jerome A , Walker Sandra A N , MacFadden Derek R , Daneman Nick
Published: September 2020

Background

A patient’s prior cultures can inform the subsequent risk of infection from resistant organisms, yet prescribers often fail to incorporate these results into their empiric antibiotic selection. Given that timely initiation of adequate antibiotics has been associated with improved outcomes, there is an urgent need to address this gap.

Methods

In order to better incorporate prior culture results in the selection of empiric antibiotics, we performed a pragmatic, prospective, hospital-wide intervention: (1) empiric antibiotic prescriptions were assessed for clinically significant discordance with the most recent methicillin-resistant Staphylococcus aureus (MRSA) surveillance swab, previous cultures for extended-spectrum beta-lactamases (ESBLs), and the most recent culture for a Gram-negative (GN) organism; and (2) if discordant, an antimicrobial stewardship pharmacist provided recommendations for alternative therapy. The impact was analyzed using a quasi-experimental design comparing two 9-month periods (pre- and postintervention) at a large academic, tertiary care institution.

Results

Clinically significant discordance was identified 99 times in the preintervention period and 86 times in the intervention period. The proportion of patients that received concordant therapy increased from 73% (72/99) in the control group to 88% (76/86) in the intervention group (P = .01). The median time to concordant therapy was shorter in the intervention group than the control group (25 vs 55 hrs, respectively; P < .001; adjusted hazard ratio = 1.95 [95% confidence interval {CI}, 1.37–2.77; P < .001]). The median duration of unnecessary vancomycin therapy was reduced by 1.1 days (95% CI, .5–1.6 days; P < .001).

Conclusions

This intervention improved prescribing, with a shorter time to concordant therapy and an increased proportion of patients receiving empiric therapy concordant with prior culture results. The use of unnecessary vancomycin was also reduced.
Infliximab, Immunomodulators and Treatment Failures in Paediatric and Adolescent Patients with Crohn’s Disease: a Nationwide Cohort Study
Authors: Lund Ken , Larsen Michael Due , Knudsen Torben , Kjeldsen Jens , Nielsen Rasmus Gaardskær , Mertz Nørgård Bente
Published: September 2020

Background and Aims

In paediatric patients with Crohn’s disease, the role of combination therapy, infliximab plus immunomodulators [thiopurine or methotrexate], is debated and data are sparse. We examined whether infliximab plus immunomodulators, compared to infliximab therapy alone, reduces the risk of treatment failure measured by intestinal surgery or switching type of anti-tumour necrosis factor [TNF] α agent within 24 months.

Design

Using Danish registries, we identified patients with Crohn’s disease, aged ≤ 20 years at the time of the first infliximab treatment, and retrieved data on their co-medications. We used Cox regression models to examine surgery or switching type of anti-TNFα agent from January 1, 2003 to December 31, 2015.

Results

We included 581 patients. The 2-year cumulative percentage of surgery was 8.5% among patients receiving combination therapy and 14.5% in those receiving infliximab alone. The adjusted 2-year hazard ratio [HR] of surgeries was 0.53 (95% confidence interval [CI] 0.32–0.88) in patients receiving combination therapy, compared to patients receiving infliximab alone. When examining a switch of anti-TNFα we included 536 patients. Within 2 years, 18.3% experienced a switch among patients receiving combination therapy and 24.8% in patients treated with infliximab alone, corresponding to an adjusted HR of 0.66 [95% CI 0.45–0.97] in patients receiving combination therapy.

Conclusions

The HR of intestinal surgeries and the risk of a switch to another anti-TNFα was reduced in paediatric and adolescent patients receiving combination therapy, compared to patients receiving only infliximab. These results suggest a benefit for infliximab therapy combined with immunomodulators, but these need to be confirmed in data with additional clinical information.
Buying Informed Voters: New Effects of Information on Voters and Candidates
Authors: Cruz Cesi , Keefer Philip , Labonne Julien
Published: September 2020

Despite the prominence of information in theories of electoral accountability, providing voters with information often fails to improve politician performance. Using two experiments in the Philippines, we show that when voters are unfamiliar with basic government capabilities, merely informing them of what politicians could do is sufficient to decrease support for incumbents. However, politicians can counteract this decrease in support by increasing clientelistic practices such as vote buying. Our work shows how even neutral information campaigns can improve the leverage of voters vis-à-vis their politicians, offering guidance for the design of interventions to change the electoral equilibrium in clientelistic countries.
Making a Dent in Dent Disease
Authors: Shipman Katherine E , Weisz Ora A
Published: September 2020

Dent disease (DD) is a rare kidney disorder caused by mutations in the Cl−/H+ exchanger ClC-5. Extensive physiologic characterization of the transporter has begun to illuminate its role in endosomal ion homeostasis. Nevertheless, we have yet to understand how loss of ClC-5 function in the kidney proximal tubule impairs membrane traffic of megalin and cubilin receptors to cause the low molecular weight proteinuria characteristic of DD. This review identifies open questions that remain to be answered, evaluates the current literature addressing these questions, and suggests new testable models that may link loss of ClC-5 function to tubular proteinuria in DD.
The Relationship Between Career Success and Sense of Purpose: Examining Linkages and Changes
Authors: Weston Sara J , Cardador M Teresa , Hill Patrick L , Schwaba Ted , Lodi-Smith Jennifer , Whitbourne Susan K
Published: September 2020

Objectives

Although researchers have linked sense of purpose to working status, there are few studies examining how specific characteristics of work may correlate with sense of purpose. The aim of the current study is to extend prior research by assessing the degree to which objective and subjective forms of career success—occupational prestige and work satisfaction—are associated with levels of and changes in sense of purpose.

Methods

Participants were part of the Rochester Adult Longitudinal Study (N = 307), which contains multiple cohorts of participants each assessed at multiple waves (full age range: 42–71). We used cross-lagged modeling to test the relationships in our model.

Results

Occupational prestige was not associated with sense of purpose levels and change. However, work satisfaction was positively associated with higher levels of sense of purpose initially, and there was evidence that changes in the 2 constructs were positively correlated.

Discussion

These findings suggest that subjective career success may be more important for sense of purpose than more objective indicators. Findings are discussed with respect to study limitations and guidance for future researchers using secondary data.
Within-Couple Personality Concordance Over Time: The Importance of Personality Synchrony for Perceived Spousal Support
Authors: Lewis Nathan A , Yoneda Tomiko
Published: September 2020

Objectives

Within-couple similarities in personality traits tend to be positively associated with relationship well-being. However, research in this area is typically based on cross-sectional designs, thereby limiting examination of longitudinal personality concordance. Given that life experiences shape within-person change in personality, and that partners within a couple often experience similar life events, investigation of within-couple personality synchrony and associations with marital outcomes is warranted.

Methods

Using data from 3,988 couples (mean age at baseline = 67.0 years, SD = 9.6), multilevel dyadic growth models estimated within-couple similarity in baseline levels, change, and occasion-to-occasion variability for each of the Big Five personality traits over an 8-year follow-up. Bivariate growth models examined the effect of within-couple similarity on perceived spousal support, accounting for dependency within couples.

Results

Adjusting for baseline age, education, functional ability, and relationship length, analyses revealed within-couple concordance between baseline levels of all 5 personality traits, as well as correlated within-couple fluctuations in neuroticism, extraversion, and openness over time. Similarity in openness, agreeableness, and neuroticism trajectories predicted spousal support. Couples were most similar in openness, showing correlated intercepts, change, and variability, and this longitudinal synchrony was particularly important for perceived spousal support in women.

Discussion

These findings provide evidence for longitudinal personality synchrony over time within older adult couples. Further, concordance in neuroticism, extraversion, and openness predicted perceived spousal support, though there may be some gender differences in personality dynamics and relationship well-being. Effects of similarity were relatively small compared to actor and partner effects of these traits.
Creating Affirmative and Inclusive Practices When Providing Genetic and Genomic Diagnostic and Research Services to Gender-Expansive and Transgender Patients
Authors: Theisen J Graham , Amarillo Ina E
Published: September 2020

Background

Gender expansive and transgender (GET) healthcare extends beyond gender-affirming therapies, reaching every medical specialty and subspecialty. As the number of GET patients seeking health services has increased, so has the need for standards of care regarding GET-affirmative practices throughout the healthcare system. As such, the number of publications surrounding GET-affirmative practices has steadily risen. However, even as such research has gained ground in other areas, one realm in which there has been a relative lag is genetics and genomics (GG).

Content

In this article, we track the GET patient and their laboratory sample from the clinic to the GG laboratory and back. Throughout the preanalytical, analytical, and postanalytical phases, we identify publications, recommendations, and guidelines relevant to the care of the GET community. We also identity knowledge gaps in each area and provide recommendations for affirmative and inclusive processes for addressing those gaps.

We have identified the practices involved in GG services that would benefit from GET-affirmative process improvement, reviewing relevant affirmative guidelines. Where guidelines could not be found, we identified those knowledge gaps and suggested potential solutions and future directions for implementing GET-affirmative practices.
Development and Clinical Evaluation of a High-Throughput LC–MS/MS Assay for Vitamin B6 in Human Plasma and Serum
Authors: Kushnir Mark M , Song Boya , Yang Evelyn , Frank Elizabeth L
Published: September 2020

Background

Pyridoxal 5′-phosphate (PLP) is the primary circulatory form of vitamin B6, an essential cofactor for numerous biochemical enzymatic reactions. Conventional PLP analysis using high-performance liquid chromatography (HPLC) with fluorescence requires derivatization and long injection-to-injection time. Development of high-throughput LC–MS/MS assays is desirable.

Methods

Stable isotope labeled internal standard was added to aliquots of samples, proteins were precipitated using trichloroacetic acid, and supernatants were analyzed by multiple reaction monitoring using LC–MS/MS in positive ion mode. Analysis time for PLP was 3.0 min using single column HPLC separation and 2.4 min using alternating column regeneration (ACR). Clinical evaluation of the method included review of results (n = 102 386) from routine performance of the assay.

Results

The assay was linear to 500 nmol/L; limit of quantification was 5 nmol/L. Imprecision (CV) of the assay was <5%. Equivalent performance was observed for single HPLC column and ACR. In 62% of routinely analyzed patient samples, PLP concentrations were within the reference interval; higher PLP concentrations were observed in samples from males than from females. Vitamin B6 deficiency was lowest in children and highest in elderly adults. Lower PLP concentrations were observed in samples collected during winter/spring than during summer/fall. We observed lower concentrations in plasma collected in lithium heparin tubes, suggesting PLP degradation caused by the anticoagulant.

Conclusions

This LC–MS/MS method allows PLP determination using simple sample preparation and short analysis time. We observed association of PLP concentrations with age, sex, and season of sample collection. Our data indicate that lithium heparin anticoagulant tubes reduce measured PLP concentration.
Stimulation of exosome biogenesis by adiponectin, a circulating factor secreted from adipocytes
Authors: Kita Shunbun , Shimomura Iichiro
Published: September 2020

Adiponectin is an adipocyte-derived circulating factor that protects various organs and tissues. Such a pleiotropic action mechanism has not yet been fully explained. Clinically important multimer adiponectin existing in serum bound to cells expressing T-cadherin, a glycosylphosphatidylinositol-anchored cadherin, but not to the cells expressing other known receptors, AdipoRs or calreticulin. Adiponectin bound to the cell-surface, accumulated inside of multivesicular bodies through T-cadherin, and increased exosome biogenesis and secretion from the cells. Such increased exosome production accompanied the reduction of cellular ceramides in endothelial cells and mouse aorta, and enhanced skeletal muscle regeneration. Significantly lower plasma exosome levels were found in mice genetically deficient in either adiponectin or T-cadherin. Therapeutic effects of mesenchymal stem cells (MSCs) for a pressure overload-induced heart failure in mice required the presence of adiponectin in plasma, T-cadherin expression and exosome biogenesis in MSCs themselves, accompanying an increase of plasma exosomes. Essentially all organs seem to have MSCs and/or their related somatic stem cells expressing T-cadherin. Our recent studies suggested the importance of exosome-stimulation by multimer adiponectin in its well-known pleiotropic organ protections.
A Retrospective Study of Factors Influencing the Survival of Modified Meek Micrografting in Severe Burn Patients
Authors: Zhang Peng , Wang Wensheng , Hu Gaozhong , Yuan Lili , Ma Siyuan , Luo Jia , Song Huapei , Huang Yuesheng , Xiang Fei
Published: September 2020

Modified Meek micrografting is a common method for treating severe burn patients. This study was to analyze the factors affecting the survival of modified Meek micrografting, thereby improving the survival rate of skin grafts. Eighty-three patients who underwent modified Meek micrografting were analyzed. According to the survival rate of skin graft after operation, the patients were divided into good skin survival group (GSSG, survival rate ≥ 70%, 47 cases) and poor skin survival group (PSSG, survival rate < 70%, 36 cases). The baseline data, surgical information, perioperative laboratory indicators, and prognosis of the patients were statistically analyzed. The univariate analysis and repeated measurement showed the burn severity, Meek skin graft area, duration of anesthesia, the postoperative sepsis shock, the mortality, the neutrophils percentage on the third day after surgery (NEU3), and the growth rate of neutrophils percentage from the first to third day after surgery (NEU3-1%) in the GSSG were significantly lower than those in the PSSG, whereas the perioperative average albumin levels and the perioperative average pre-albumin levels were higher. Receiver operating characteristic curve showed that the NEU3 had a good predictive value for the survival of skin slices. Maintaining perioperative albumin levels at a high level, controlling perioperative infection, and shortening the operation time as much as possible may improve the survival rate of modified Meek micrografting.
Biodiversity and host specificity of sponge-associated barnacles (Cirripedia: Thoracica) in Thailand
Authors: Yu Meng-Chen , Chan Benny K K , Kolbasov Gregory A , Ganmanee Monthon
Published: September 2020

We examined the diversity and host use of sponge-associated barnacles of Thailand (Andaman Sea and the Gulf of Thailand) using a combined morphological and molecular approach. Eight barnacle species (including two new species) were collected from 12 host sponges. Host-specific barnacle species includes Acasta lappasp. nov., which exclusively inhabits the sponge Mycale sp. Acasta milkaesp. nov. was only collected from the sponge Callyspongia cf. diffusa (Ridley, 1884). Multatria filigranus (Broch, 1916) were found in the encrusting soft sponges Monanchora unguiculata (Dendy, 1922) and Clathria sp. Pyrgospongia stellula (Rosell, 1975) inhabits the sponges Spheciospongia vagabunda (Ridley, 1884). Generalist barnacle species includes Euacsta ctenodentia (Rosell, 1972), E. porata (Nilsson-Cantell, 1921), E. zuiho (Hiro, 1936), and Acasta cyathus Darwin, 1854, which inhabit a wide range of sponges with various textures.