bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Fingerprint of Turner Syndrome
Authors: Bugajska Jolanta , Berska Joanna , Wójcik Małgorzata , Starzyk Jerzy B. , Sztefko Krystyna
Published: March 2020

Girls with Turner syndrome (TS) are at increased risk of developing insulin resistance and coronary artery disease as a result of hypertension and obesity frequently seen in these patients. On the other hand, it is known that obesity is associated with increased serum levels of branched-chain amino acids (BCAAs: valine; leucine and isoleucine) and aromatic amino acids. The aim of the study is to compare the metabolic fingerprint of girls with TS to the metabolic fingerprint of girls with obesity. Metabolic fingerprinting using an untargeted metabolomic approach was examined in plasma from 46 girls with TS (study group) and 22 age-matched girls with obesity (control group). The mean values of BCAAs, methionine, phenylalanine, lysine, tryptophan, histidine, tyrosine, alanine and ornithine were significantly lower in the study group than in the control (p from 0.0025 to <0.000001). Strong significant correlation between BCAAs, phenylalanine, arginine, tyrosine, glutamic acid, citrulline and alanine, and body mass index expressed as standard deviation score BMI-SDS in the patients with obesity (p from 0.049 to 0.0005) was found. In contrast; there was no correlation between these amino acids and BMI-SDS in the girls with TS. It is suggested that obesity in patients with TS is not associated with altered amino acids metabolism.
Social Capital in Community Organizing for Land Protection and Food Security
Authors: Cheevapattananuwong Pornsiri , Baldwin Claudia , Lathouras Athena , Ike Nnenna
Published: March 2020

Since 2016, the Thai Government has pursued a twenty-year national economic growth policy, Thailand 4.0, promoting innovation and stimulating international investment through the Eastern Economic Corridor (EEC) project. The EEC project involves significant land acquisition resulting in the need to relocate villagers with potential impact on food security in a major food production area. This research explored the concerns of a local farming community regarding the potential loss of their farmland and means of livelihood under the EEC project using a case study in Ban Pho District of Chachoengsao (CCS) province. It described their resulting action to protect their farmland using community organizing. Data was collected through documents, observation and semi-structured interviews of key stakeholders. The results demonstrate the role of social capital in community organizing. We contend that high social capital stock is a necessary precursor to create conditions for community members to take steps to defend and protect their interests. This paper contributes to a deeper understanding of the role of social capital in community organizing in cases involving natural resource management.
Going Beyond Panaceas: The Diversity of Land Observatory Forms in Africa
Authors: Grislain Quentin , Bourgoin Jeremy , Anseeuw Ward , Burnod Perrine , Hershaw Eva , Diop Djibril
Published: March 2020

In recent decades, mechanisms for observation and information production have proliferated in an attempt to meet the growing needs of stakeholders to access dynamic data for the purposes of informed decision-making. In the land sector, a growing number of land observatories are producing data and ensuring its transparency. We hypothesize that these structures are being developed in response to the need for information and knowledge, a need that is being driven by the scale and diversity of land issues. Based on the results of a study conducted on land observatories in Africa, this paper presents existing and past land observatories on the continent and proposes to assess their diversity through an analysis of core dimensions identified in the literature. The analytical framework was implemented through i) an analysis of existing literature on land observatories, ii) detailed assessments of land observatories based on semi-open interviews conducted via video conferencing, iii) fieldwork and visits to several observatories, and iv) participant observation through direct engagement and work at land observatories. We emphasize that the analytical framework presented here can be used as a tool by land observatories to undertake ex-post self-evaluations that take the observatory’s trajectory into account, or in the case of proposed new land observatories, to undertake ex-ante analyses and design the pathway towards the intended observatory.
Impacts of Land Ownership on the Economic Performance and Viability of Rice Farming in Thailand
Authors: Pochanasomboon Amorn , Attavanich Witsanu , Kidsom Akaranant
Published: March 2020

This article evaluates the impacts of land ownership on the economic performance and viability of rice farming in Thailand, and explores whether they are heterogeneous across different types of farming while using the propensity score matching (PSM) technique. This study categorizes land ownership into two types: full land ownership and weak land ownership. We reveal that full land ownership enhances the rice yield of small and midsize farms, with values of 115.789–127.414 kg/hectare and 51.926–70.707 kg/hectare, respectively. On the other hand, weak land ownership only enhances the rice yield of small farms, with an increased yield of 65.590–72.574 kg/hectare. Full land ownership also helps to reduce the informal debt of small and midsize farms by $16.972–$24.877 per farm and $31.393–$37.819 per farm, respectively. On the other hand, weak land ownership helps to reduce the informal debt of midsize farms, ranging from $36.909 to $44.681 per farm. Therefore, policy makers should encourage small and midsize farm households to adopt full land ownership instead of weak land ownership, as this will provide the greatest benefits to farm households and efficient land use.
A Clear Past and a Murky Future: Life in the Anthropocene on the Pampana River, Sierra Leone
Authors: Marcantonio Richard , Fuentes Agustin
Published: March 2020

The impacts of human activities on ecosystems are significantly increasing the rate of environmental change in the earth system, reshaping the global landscape. The rapid rate of environmental change is disrupting the ability of millions of people around the globe to live their everyday lives and maintain their human niche. Evidence suggests that we have entered (or created) a new epoch, the Anthropocene, which is defined as the period in which humans and human activities are the primary drivers of planetary change. The Anthropocene denotes a global shift, but it is the collective of local processes. This is our frame for investigating local accounts of human-caused disruptive environmental change in the Pampana River in Tonkolili District, Northern Province, Sierra Leone. Since the end of the Sierra Leonean civil war in 2002, the country has experienced a rapid increase in extractive industries, namely mining. We explored the effects of this development by working with communities along the Pampana River in Tonkolili, with a specific focus given to engaging local fishermen through ethnographic interviews (N = 21 fishermen and 33 non-fishermen), focus group discussions (N = 21 fishermen), and participant observation. We deployed theoretical and methodological frameworks from human niche construction theory, complex adaptive systems, and ethnography to track disruptive environmental change in and on the Pampana from upstream activities and the concomitant shifts in the local human niche. We highlight the value of integrating ethnographic methods with human evolutionary theory, produce important insights about local human coping processes with disruptive environmental change, and help to further account for and understand the ongoing global process of human modification of the earth system in the Anthropocene.
Bio-Based Polyurethane Composite Foams with Improved Mechanical, Thermal, and Antibacterial Properties
Authors: Członka Sylwia , Strąkowska Anna , Strzelec Krzysztof , Kairytė Agnė , Kremensas Arūnas
Published: March 2020

Among different organic fillers, the chemical composition of Syzygium aromaticum, commonly known as cloves, has great potential as a sustainable reinforcement for polymeric materials. In the study, grounded cloves were used as cellulosic filler for a novel polyurethane (PU) composite foams. Soybean oil-based PU composite foams were successfully reinforced with different concentrations (1, 2, and 5 wt%) of clove filler. PU foams were examined by rheological behavior, processing parameters, cellular structure (scanning electron microscopy analysis), mechanical properties (compression test, impact test, three-point bending test), thermal properties (thermogravimetric analysis), viscoelastic behavior (dynamic mechanical analysis) as well as selected application properties (apparent density, dimensional stability, surface hydrophobicity, water absorption, color characteristic). In order to undertake the disc diffusion method, all PU composites were tested against selected bacteria (Escherichia coli and Staphylococcus aureus). Based on the results, it can be concluded that the addition of 1 and 2 wt% of clove filler leads to PU composite foams with improved compression strength (improvement by ≈18% for sample PU-1), greater flexural strength (increase of ≈11%), and improved impact strength (increase of ≈8%). Moreover, it has been proved that clove filler may be used as a natural anti-aging compound for polymeric materials. Based on the antibacterial results, it has been shown that the addition of clove filler significantly improved the antibacterial properties of PU foams and is suitable for the manufacturing of antimicrobial PU composite foams. Due to these positive and beneficial effects, it can be stated that the use of cloves as a natural filler in PU composite foams can promote a new application path in converting agricultural waste into useful resources for creating a new class of green materials.
From Fractional Quantum Mechanics to Quantum Cosmology: An Overture
Authors: Moniz Paulo Vargas , Jalalzadeh Shahram
Published: March 2020

Fractional calculus is a couple of centuries old, but its development has been less embraced and it was only within the last century that a program of applications for physics started. Regarding quantum physics, it has been only in the previous decade or so that the corresponding literature resulted in a set of defying papers. In such a context, this manuscript constitutes a cordial invitation, whose purpose is simply to suggest, mostly through a heuristic and unpretentious presentation, the extension of fractional quantum mechanics to cosmological settings. Being more specific, we start by outlining a historical summary of fractional calculus. Then, following this motivation, a (very) brief appraisal of fractional quantum mechanics is presented, but where details (namely those of a mathematical nature) are left for literature perusing. Subsequently, the application of fractional calculus in quantum cosmology is introduced, advocating it as worthy to consider: if the progress of fractional calculus serves as argument, indeed useful consequences will also be drawn (to cite from Leibnitz). In particular, we discuss different difficulties that may affect the operational framework to employ, namely the issues of minisuperspace covariance and fractional derivatives, for instance. An example of investigation is provided by means of a very simple model. Concretely, we restrict ourselves to speculate that with minimal fractional calculus elements, we may have a peculiar tool to inspect the flatness problem of standard cosmology. In summary, the subject of fractional quantum cosmology is herewith proposed, merely realised in terms of an open program constituted by several challenges.
On the Use of Probabilistic Worst-Case Execution Time Estimation for Parallel Applications in High Performance Systems
Authors: Fusi Matteo , Mazzocchetti Fabio , Farres Albert , Kosmidis Leonidas , Canal Ramon , Cazorla Francisco J. , Abella Jaume
Published: March 2020

Some high performance computing (HPC) applications exhibit increasing real-time requirements, which call for effective means to predict their high execution times distribution. This is a new challenge for HPC applications but a well-known problem for real-time embedded applications where solutions already exist, although they target low-performance systems running single-threaded applications. In this paper, we show how some performance validation and measurement-based practices for real-time execution time prediction can be leveraged in the context of HPC applications on high-performance platforms, thus enabling reliable means to obtain real-time guarantees for those applications. In particular, the proposed methodology uses coordinately techniques that randomly explore potential timing behavior of the application together with Extreme Value Theory (EVT) to predict rare (and high) execution times to, eventually, derive probabilistic Worst-Case Execution Time (pWCET) curves. We demonstrate the effectiveness of this approach for an acoustic wave inversion application used for geophysical exploration.
Output-Space Branch-and-Bound Reduction Algorithm for a Class of Linear Multiplicative Programs
Authors: Zhang Bo , Gao Yuelin , Liu Xia , Huang Xiaoli
Published: March 2020

In this paper, a new relaxation bounding method is proposed for a class of linear multiplicative programs. Although the 2 p − 1 variable is introduced in the construction of equivalence problem, the branch process of the algorithm is only carried out in p − dimensional space. In addition, a super-rectangular reduction technique is also given to greatly improve the convergence rate. Furthermore, we construct an output-space branch-and-bound reduction algorithm based on solving a series of linear programming sub-problems, and prove the convergence and computational complexity of the algorithm. Finally, to verify the feasibility and effectiveness of the algorithm, we carried out a series of numerical experiments and analyzed the advantages and disadvantages of the algorithm by numerical results.
Optimization of the Solution of a Dispersion Model
Authors: Dimache Alexandru-Nicolae , Groza Ghiocel , Jianu Marilena , Perju Sorin , Rece Laurențiu , Harničárová Marta , Valíček Jan
Published: March 2020

The study of the combination of chemical kinetics with transport phenomena is the main step for reactor design. It is possible to deviate from the model behaviour, the cause of which may be fluid channelling, fluid recirculation, or creation of stagnant regions in the vessel, by using a dispersion model. In this paper, the known general solution of the dispersion model for closed vessels is given in a new, straightforward form. In order to improve the classical theoretical solution, a hybrid of analytical and numerical methods is used. It is based on the general analytic solution and the least-squares method by fitting the results of a tracer test carried out on the vessel with the values of the analytic solution. Thus, the accuracy of the estimation for the vessel dispersion number is increased. The presented method can be used to similar problems modelled by a partial differential equation and some boundary conditions which are not sufficient to ensure the uniqueness of the solution.
On the (29, 5)-Arcs in PG(2, 7) and Some Generalized Arcs in PG(2, q)
Authors: Bouyukliev Iliya , Cheon Eun Ju , Maruta Tatsuya , Okazaki Tsukasa
Published: March 2020

Using an exhaustive computer search, we prove that the number of inequivalent ( 29 , 5 ) -arcs in PG ( 2 , 7 ) is exactly 22. This generalizes a result of Barlotti (see Barlotti, A. Some Topics in Finite Geometrical Structures, 1965), who constructed the first such arc from a conic. Our classification result is based on the fact that arcs and linear codes are related, which enables us to apply an algorithm for classifying the associated linear codes instead. Related to this result, several infinite families of arcs and multiple blocking sets are constructed. Lastly, the relationship between these arcs and the Barlotti arc is explored using a construction that we call transitioning.
A Variation of the ATC Work Shift Scheduling Problem to Deal with Incidents at Airport Control Centers
Authors: Jiménez-Martín Antonio , Tello Faustino , Mateos Alfonso
Published: March 2020

This paper deals with a variation of the air traffic controller (ATC) work shift scheduling problem focusing on the tactical phase, in which the plan for the day of operations can be modified according to real-time traffic demand or other possible incidents (one or more ATCs become sick and/or there is an increase in unplanned air traffic), which may lead to a new sectorization and a lower number of available ATCs. To deal with these issues, we must reassign the available ATCs to the new sectorization established at the time the incident happens, but also taking into account the work done by the ATCs up to that point. We propose a new methodology consisting of two phases. The goal of the first phase is to build an initial possibly infeasible solution, taking into account the sectors that have been closed or opened in the new sectorization, together with the ATCs available after the incident. In the second phase, we use simulated annealing (SA) and variable neighborhood search (VNS) metaheuristics to derive a feasible solution in which the available ATCs are used and all the ATC labor conditions are met. A weighted additive objective function is used in this phase to account for the feasibility of the solution but also for the number of changes in the control center at the time the incident happens and the similarity of the derived solution with templates usually used by the network manager operations center, a center managing the air traffic flows of an entire network of control centers. The methodology is illustrated by means of seven real instances provided by the Air Traffic Management Research, Development and Innovation Reference Center (CRIDA) experts representing possible incidents that may arise. The solutions derived by SA outperform those reached by VNS in terms of both the number of violated constraints in all seven instances, and solution compactability in six out the seven instances, and both are very similar with regard to the number of control center changes at the time of the incident. Although computation times for VNS are clearly better than for SA, CRIDA experts were satisfied with SA computation times. The solutions reached by SA were preferred.
Good (and Not So Good) Practices in Computational Methods for Fractional Calculus
Authors: Diethelm Kai , Garrappa Roberto , Stynes Martin
Published: March 2020

The solution of fractional-order differential problems requires in the majority of cases the use of some computational approach. In general, the numerical treatment of fractional differential equations is much more difficult than in the integer-order case, and very often non-specialist researchers are unaware of the specific difficulties. As a consequence, numerical methods are often applied in an incorrect way or unreliable methods are devised and proposed in the literature. In this paper we try to identify some common pitfalls in the use of numerical methods in fractional calculus, to explain their nature and to list some good practices that should be followed in order to obtain correct results.
Marine Alkaloids with Anti-Inflammatory Activity: Current Knowledge and Future Perspectives
Authors: Souza Cássio R. M. , Bezerra Wallace P. , Souto Janeusa T.
Published: March 2020

Alkaloids are nitrogenous compounds with various biological activities. Alkaloids with anti-inflammatory activity are commonly found in terrestrial plants, but there are few records of the identification and characterization of the activity of these compounds in marine organisms such as fungi, bacteria, sponges, ascidians, and cnidarians. Seaweed are a source of several already elucidated bioactive compounds, but few studies have described and characterized the activity of seaweed alkaloids with anti-inflammatory properties. In this review, we have gathered the current knowledge about marine alkaloids with anti-inflammatory activity and suggest future perspectives for the study and bioprospecting of these compounds.
Functionally-Graded Metallic Syntactic Foams Produced via Particle Pre-Compaction
Authors: Fiedler Thomas , Movahedi Nima , York Lucas , Broxtermann Steffen
Published: March 2020

This paper introduces a novel functionally graded metallic syntactic foam. The investigated foams are manufactured while using infiltration casting where molten A356 aluminum flows into the interstitial voids of packed expanded perlite (EP) particle beds. The partial pre-compaction of particle beds enables the creation of distinct and reproducible density gradients within the syntactic foam. In this study, the samples are produced using four gradually increasing compaction forces and are compared to non-compacted samples. X-ray imaging is used to detect the resulting spatial variation of foam density. In addition, quasi-static compression tests are performed to determine the mechanical foam properties. The results suggest that particle pre-compaction is an efficient tool for tailoring the density and mechanical properties of these novel functionally graded materials.
Refining As-Cast Structures of Novel SixTiVCrZr High-Entropy Alloys Using Estimated Effective Solidification Temperature Obtained Using Chvorinov’s Rule
Authors: Leong Zhaoyuan , Huang Yuhe , Bloomfield Maximillian , Jim Bethany , Kerridge George , Pitcairn Jem , Schobitz Michael , Sinclair Lorna , Zilinskaite Silvija , Goodall Russell
Published: March 2020

High-entropy alloys (HEAs), i.e., multicomponent alloys where (typically five or more) elements are combined in equal, or roughly equal, quantities, are of great current interest, due to their formation of single, simple structured phases, and the unusual properties they can potentially exhibit. Phase presence may be predicted using semi-empirical methods, but deviations from predictions may be seen during the course of alloy synthesis, with the formation of unexpected phases. The generation of such phases may be controlled with knowledge of the effective solidification temperature; in this full article, Chvorinov’s rule for solidification time is used to estimate this temperature as part of the design of a new multiphase alloy system, TiVCrZr-Six. Further heat treatment of the TiVCrZr-Si system confirms the applicability of this approach. The new compositions demonstrate mechanical properties that suggest potential for optimization for high-temperature applications.
Study on Grinding and Deformation Fracture Control of Cold Rolled Titanium Strip
Authors: Zhang Jiaming , Yu Wei , Dong Entao , Zhang Zeyu , Shi Jiaxin , Gong Gaoxiang
Published: March 2020

Surface defects of titanium strip need to be removed by local grinding, but local cracking or band breaking then occurs during subsequent cold rolling. Tensile properties and deformation resistance of 3 mm thick commercially pure titanium strip with grinding pits on the surface were simulated by a finite-element method using a multi-pass cold-rolling deformation process. The stress and strain of grinding pits with depths of 0.25–2 mm were analyzed. During cold-rolling deformation, the stress and strain in the center of a grinding pit were larger than at the edge region. The strip was first subjected to tensile stress in the rolling direction, which then decreased and gradually changed to compressive stress. Partial stress was larger in the rolling direction than in the transverse direction. When the tensile stress and true strain both exceeded the stress and strain limits during second-pass rolling, the strip with a grinding depth of 2 mm cracked, but shallower grinding pits were repaired. The criterion for cracking during rolling after grinding is that the maximum tensile strain at the bottom of the pit must be less than the critical strain of the material: ln ( 1 + h / H ) ≤ ε C r . Results of numerical simulation were verified by the data for cold-rolling tests.
Selective and Mutual Separation of Palladium (II), Platinum (IV), and Rhodium (III) Using Aliphatic Primary Amines
Authors: Matsumoto Kazuya , Sezaki Yuto , Yamakawa Sumito , Hata Yuki , Jikei Mitsutoshi
Published: March 2020

The selective recovery of platinum-group metals (PGMs) remains a huge challenge. Although solvent extraction processes are generally used for PGM separation, the use of organic solvents is problematic because of their toxicity and environmental concerns. Here, we have developed a new PGM recovery method by precipitation from hydrochloric acid (HCl) solutions containing Pd(II), Pt(IV), and Rh(III) using aliphatic primary amines as precipitants. Pt(IV) was precipitated using the amines with alkyl chains longer than hexyl independent of HCl concentration. The precipitation of Pd(II) required longer alkyl amines than octyl, regardless of the HCl concentration. Rh(III) was recovered by precipitation at high HCl concentrations using the amines longer than hexyl. The mutual separation of Pt(IV), Rh(III), and Pd(II), in this order, was successfully achieved by changing the HCl concentrations and alkyl chain lengths of the amines. X-ray photoelectron spectroscopy and thermogravimetric analysis evidently showed that the metal-containing precipitates were ion-pair complexes composed of metal chloro-complex anions and ammonium cations.
Reducing the Magnesium Content from Seawater to Improve Tailing Flocculation: Description by Population Balance Models
Authors: Quezada Gonzalo R. , Jeldres Matías , Toro Norman , Robles Pedro , Jeldres Ricardo I.
Published: March 2020

Experimental assays and mathematical models, through population balance models (PBM), were used to characterize the particle aggregation of mining tailings flocculated in seawater. Three systems were considered for preparation of the slurries: i) Seawater at natural pH (pH 7.4), ii) seawater at pH 11, and iii) treated seawater at pH 11. The treated seawater had a reduced magnesium content in order to avoid the formation of solid complexes, which damage the concentration operations. For this, the pH of seawater was raised with lime before being used in the process—generating solid precipitates of magnesium that were removed by vacuum filtration. The mean size of the aggregates were represented by the mean chord length obtained with the Focused beam reflectance measurement (FBRM) technique, and their descriptions, obtained by the PBM, showed an aggregation and a breakage kernel had evolved. The fractal dimension and permeability were included in the model in order to improve the representation of the irregular structure of the aggregates. Then, five parameters were optimized: Three for the aggregation kernel and two for the breakage kernel. The results show that raising the pH from 8 to 11 was severely detrimental to the flocculation performance. Nevertheless, for pH 11, the aggregates slightly exceeded 100 µm, causing undesirable behaviour during the thickening operations. Interestingly, magnesium removal provided a suitable environment to perform the tailings flocculation at alkaline pH, making aggregates with sizes that exceeded 300 µm. Only the fractal dimension changed between pH 8 and treated seawater at pH 11—as reflected in the permeability outcomes. The PBM fitted well with the experimental data, and the parameters showed that the aggregation kernel was dominant at all-polymer dosages. The descriptive capacity of the model might have been utilized as a support in practical decisions regarding the best-operating requirements in the flocculation of copper tailings and water clarification.
Improved Dried Blood Spot-Based Metabolomics: A Targeted, Broad-Spectrum, Single-Injection Method
Authors: Li Kefeng , Naviaux Jane C. , Monk Jonathan M. , Wang Lin , Naviaux Robert K.
Published: March 2020

Dried blood spots (DBS) have proven to be a powerful sampling and storage method for newborn screening and many other applications. However, DBS methods have not yet been optimized for broad-spectrum targeted metabolomic analysis. In this study, we developed a robust, DBS-based, broad-spectrum, targeted metabolomic method that was able to measure over 400 metabolites from a 6.3 mm punch from standard Whatman 903TM filter paper cards. The effects of blood spot volumes, hematocrit, vacutainer chemistry, extraction methods, carryover, and comparability with plasma and fingerstick capillary blood samples were analyzed. The stability of over 400 metabolites stored under varying conditions over one year was also tested. No significant impacts of blood volume and hematocrit variations were observed when the spotted blood volume was over 60 µL and the hematocrit was between 31% and 50%. The median area under the curve (AUC) of metabolites in the DBS metabolome declined by 40% in the first 3 months and then did not decline further for at least 1 year. All originally detectable metabolites remained within detectable limits. The optimal storage conditions for metabolomic analysis were −80 °C with desiccants and without an O2 scavenger. The method was clinically validated for its potential utility in the diagnosis of the mitochondrial disease mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). Our method provides a convenient alternative to freezing, storing, and shipping liquid blood samples for comparative metabolomic studies.
Chemical Fingerprints of Emotional Body Odor
Authors: Smeets Monique A.M. , Rosing Egge A.E. , Jacobs Doris M. , van Velzen Ewoud , Koek Jean H. , Blonk Cor , Gortemaker Ilse , Eidhof Marloes B. , Markovitch Benyamin , de Groot Jasper , Semin Gün R.
Published: March 2020

Chemical communication is common among animals. In humans, the chemical basis of social communication has remained a black box, despite psychological and neural research showing distinctive physiological, behavioral, and neural consequences of body odors emitted during emotional states like fear and happiness. We used a multidisciplinary approach to examine whether molecular cues could be associated with an emotional state in the emitter. Our research revealed that the volatile molecules transmitting different emotions to perceivers also have objectively different chemical properties. Chemical analysis of underarm sweat collected from the same donors in fearful, happy, and emotionally neutral states was conducted using untargeted two-dimensional (GC×GC) coupled with time of flight (ToF) MS-based profiling. Based on the multivariate statistical analyses, we find that the pattern of chemical volatiles (N = 1655 peaks) associated with fearful state is clearly different from that associated with (pleasant) neutral state. Happy sweat is also significantly different from the other states, chemically, but shows a bipolar pattern of overlap with fearful as well as neutral state. Candidate chemical classes associated with emotional and neutral sweat have been identified, specifically, linear aldehydes, ketones, esters, and cyclic molecules (5 rings). This research constitutes a first step toward identifying the chemical fingerprints of emotion.
Local Phenomena Shape Backyard Soil Metabolite Composition
Authors: Nguyen Tra D. , Lesani Mahbobeh , Forrest Ines , Lan Yunpeng , Dean Danya A. , Gibaut Quentin M. R. , Guo Yanting , Hossain Ekram , Olvera Marcela , Panlilio Hannah , Parab Adwaita R. , Wu Chaoyi , Bernatchez Jean A. , Cichewicz Robert H. , McCall Laura-Isobel
Published: March 2020

Soil covers most of Earth’s continental surface and is fundamental to life-sustaining processes such as agriculture. Given its rich biodiversity, soil is also a major source for natural product drug discovery from soil microorganisms. However, the study of the soil small molecule profile has been challenging due to the complexity and heterogeneity of this matrix. In this study, we implemented high-resolution liquid chromatography–tandem mass spectrometry and large-scale data analysis tools such as molecular networking to characterize the relative contributions of city, state and regional processes on backyard soil metabolite composition, in 188 soil samples collected from 14 USA States, representing five USA climate regions. We observed that region, state and city of collection all influence the overall soil metabolite profile. However, many metabolites were only detected in unique sites, indicating that uniquely local phenomena also influence the backyard soil environment, with both human-derived and naturally-produced (plant-derived, microbially-derived) metabolites identified. Overall, these findings are helping to define the processes that shape the backyard soil metabolite composition, while also highlighting the need for expanded metabolomic studies of this complex environment.
Reusable Embedded Microcoils for Magnetic Nano-Beads Trapping in Microfluidics: Magnetic Simulation and Experiments
Authors: Lefebvre Olivier , Cao Hong Ha , Cortés Francisco Meritxell , Woytasik Marion , Dufour-Gergam Elisabeth , Ammar Mehdi , Martincic Emile
Published: March 2020

In this study, a microfluidic chip with integrated coil was designed and fabricated for the aim of effectively trapping magnetic nanobeads (Adembeads®, 300 nm) and measuring the chip’s temperature during the working time. In addition, a reversible technique of bonding Polydimethylsiloxane (PDMS) channels was presented. This bonding process used a coating layer of CYTOP®product as a protection, insulation and low-adhesion layer. The reversible packaging technique allows the bottom substrate to be reused, possibly equipped with sensors, and to use a disposable microchannels network. The FE method was employed to calculate the magnetic field and power consumption by the ANSYS® version 12.1 software. Merit factors were defined in order to synthetically represent the ability of the simulated coil to trap beads for a unit power consumption, i.e. a given heat generation. The simulation results propose a new approach to optimize the design criteria in fabricating planar microcoils. The optimal microcoils were fabricated and then used to realize a magnetic immunoassay in a microfluidic chip. The aim was to integrate these microcoils into a lab-on-chip and obtain a fast and highly sensitive biological element detection.
Correction: Iqbal, S. et al. Empirical Modeling of Zn/ZnO Nanoparticles Decorated/Conjugated with Fotolon (Chlorine e6) Based Photodynamic Therapy towards Liver Cancer Treatment. Micromachines, 2019, 10, 60
Authors: Iqbal Seemab , Fakhar-e-Alam Muhammad , Atif M. , Ahmed Nasar , -ul-Ahmad Aqrab , Amin N. , Alghamdi Raed ahmed , Hanif Atif , Farooq W. Aslam
Published: March 2020

In the published paper [...]
Selenite Cystine Agar for Enumeration of Inoculated Salmonella Serovars Recovered from Stressful Conditions during Antimicrobial Validation Studies
Authors: Karolenko Caitlin E. , Bhusal Arjun , Gautam Dhiraj , Muriana Peter M.
Published: March 2020

Process validation studies often require the inoculation of select foodborne pathogens into targeted foods to determine the lethality of the process or antimicrobial ingredients, and quantitative recovery of surviving inoculum bacteria helps to make those assessments. Such processes introduce various stressors on the inoculated challenge microorganisms whereby traditional selective media are too harsh to enumerate the remaining viable and injured population quantitatively. Innate antibiotic resistance of challenge organisms has often been used to establish simple selective media (i.e., Tryptic Soy Agar/TSA + antibiotics) for recovering inoculated strains, but sometimes antibiotic resistant background microorganisms are higher than desired. Salmonella Thompson 120, Salmonella Heidelberg F5038BG1, Salmonella Hadar MF60404, Salmonella Enteritidis H3527, and Salmonella Typhimurium H3380 were characterized for antibiotic resistance and acid adaptation in Tryptic Soy Broth containing 0%, 0.25%, or 1.0% glucose. Sodium pyruvate was evaluated for recovery after stress but no enhancing effect was observed, possibly because the strains were acid-adapted. Selenite Cystine Broth, traditionally used as a selective enrichment broth, was used as the basis for Selenite Cystine Agar (SCA) in combination with three antibiotics to which our Salmonella are resistant. Serovars of Salmonella, both individually and in mixtures, were enumerated on TSA, SCA, Xylose Lysine Desoxycholate (XLD), and Hektoen Enteric (HE) selective agars (all containing the same antibiotics) after conditions of nutrient starvation, desiccation, acid stress, and thermal stress. The data show that quantitative enumeration of our Salmonella serovars on SCA was not significantly different (p > 0.05) than those achieved on TSA for all tested stress categories. Levels of Salmonella enumerated on XLD and/or HE were significantly different (p < 0.05) than on TSA and SCA and often more than 1–2-log lower, consistent with the inhibition of injured cells. These data confirm that SCA (+ antibiotics) is a suitable selective medium for enumeration of these acid-adapted Salmonella serovars as challenge organisms recovered from various conditions of stress.
Indoor Microbiome: Quantification of Exposure and Association with Geographical Location, Meteorological Factors, and Land Use in France
Authors: Rocchi Steffi , Reboux Gabriel , Scherer Emeline , Laboissière Audrey , Zaros Cécile , Rouzet Adeline , Valot Benoit , Khan Sadia , Dufourg Marie-Noëlle , Leynaert Bénédicte , Raherison Chantal , Millon Laurence
Published: March 2020

The indoor microbial community is a mixture of microorganisms resulting from outdoor ecosystems that seed the built environment. However, the biogeography of the indoor microbial community is still inadequately studied. Dust from more than 3000 dwellings across France was analyzed by qPCR using 17 targets: 10 molds, 3 bacteria groups, and 4 mites. Thus, the first spatial description of the main indoor microbial allergens on the French territory, in relation with biogeographical factors influencing the distribution of microorganisms, was realized in this study. Ten microorganisms out of 17 exhibited increasing abundance profiles across the country: Five microorganisms (Dermatophagoïdes pteronyssinus, Dermatophagoïdes spp., Streptomyces spp., Cladosporium sphaerospermum, Epicoccum nigrum) from northeast to southwest, two (Cryptococcus spp., Alternaria alternata) from northwest to southeast, Mycobacteria from east to west, Aspergillus fumigatus from south to north, and Penicillium chrysogenum from south to northeast. These geographical patterns were partly linked to climate and land cover. Multivariate analysis showed that composition of communities seemed to depend on landscapes, with species related to closed and rather cold and humid landscapes (forests, located in the northeast) and others to more open, hot, and dry landscapes (herbaceous and coastal regions, located in the west). This study highlights the importance of geographical location and outdoor factors that shape communities. In order to study the effect of microorganisms on human health (allergic diseases in particular), it is important to identify biogeographic factors that structure microbial communities on large spatial scales and to quantify the exposure with quantitative tools, such as the multi-qPCR approach.
Standardization of Plant Microbiome Studies: Which Proportion of the Microbiota is Really Harvested?
Authors: Sare Abdoul Razack , Stouvenakers Gilles , Eck Mathilde , Lampens Amber , Goormachtig Sofie , Jijakli M. Haïssam , Massart Sebastien
Published: March 2020

Studies in plant-microbiome currently use diverse protocols, making their comparison difficult and biased. Research in human microbiome have faced similar challenges, but the scientific community proposed various recommendations which could also be applied to phytobiome studies. Here, we addressed the isolation of plant microbiota through apple carposphere and lettuce root microbiome. We demonstrated that the fraction of the culturable epiphytic microbiota harvested by a single wash might only represent one-third of the residing microbiota harvested after four successive washes. In addition, we observed important variability between the efficiency of washing protocols (up to 1.6-fold difference for apple and 1.9 for lettuce). QIIME2 analysis of 16S rRNA gene, showed a significant difference of the alpha and beta diversity between protocols in both cases. The abundance of 76 taxa was significantly different between protocols used for apple. In both cases, differences between protocols disappeared when sequences of the four washes were pooled. Hence, pooling the four successive washes increased the alpha diversity for apple in comparison to a single wash. These results underline the interest of repeated washing to leverage abundance of microbial cells harvested from plant epiphytic microbiota whatever the washing protocols, thus minimizing bias.
Protein Aggregation is Associated with Acinetobacter baumannii Desiccation Tolerance
Authors: Wang Xun , Cole Cody G. , DuPai Cory D. , Davies Bryan W.
Published: March 2020

Desiccation tolerance has been implicated as an important characteristic that potentiates the spread of the bacterial pathogen Acinetobacter baumannii on dry surfaces. Here we explore several factors influencing desiccation survival of A. baumannii. At the macroscale level, we find that desiccation tolerance is influenced by cell density and growth phase. A transcriptome analysis indicates that desiccation represents a unique state for A. baumannii compared to commonly studied growth phases and strongly influences pathways responsible for proteostasis. Remarkably, we find that an increase in total cellular protein aggregates, which is often considered deleterious, correlates positively with the ability of A. baumannii to survive desiccation. We show that inducing protein aggregate formation prior to desiccation increases survival and, importantly, that proteins incorporated into cellular aggregates can retain activity. Our results suggest that protein aggregates may promote desiccation tolerance in A. baumannii through preserving and protecting proteins from damage during desiccation until rehydration occurs.
Transporters and Efflux Pumps Are the Main Mechanisms Involved in Staphylococcus epidermidis Adaptation and Tolerance to Didecyldimethylammonium Chloride
Authors: Ribič Urška , Jakše Jernej , Toplak Nataša , Koren Simon , Kovač Minka , Klančnik Anja , Jeršek Barbara
Published: March 2020

Staphylococcus epidermidis cleanroom strains are often exposed to sub-inhibitory concentrations of disinfectants, including didecyldimethylammonium chloride (DDAC). Consequently, they can adapt or even become tolerant to them. RNA-sequencing was used to investigate adaptation and tolerance mechanisms of S. epidermidis cleanroom strains (SE11, SE18), with S. epidermidis SE11Ad adapted and S. epidermidis SE18To tolerant to DDAC. Adaptation to DDAC was identified with up-regulation of genes mainly involved in transport (thioredoxin reductase [pstS], the arsenic efflux pump [gene ID, SE0334], sugar phosphate antiporter [uhpT]), while down-regulation was seen for the Agr system (agrA, arC, agrD, psm, SE1543), for enhanced biofilm formation. Tolerance to DDAC revealed the up-regulation of genes associated with transporters (L-cysteine transport [tcyB]; uracil permease [SE0875]; multidrug transporter [lmrP]; arsenic efflux pump [arsB]); the down-regulation of genes involved in amino-acid biosynthesis (lysine [dapE]; histidine [hisA]; methionine [metC]), and an enzyme involved in peptidoglycan, and therefore cell wall modifications (alanine racemase [SE1079]). We show for the first time the differentially expressed genes in DDAC-adapted and DDAC-tolerant S. epidermidis strains, which highlight the complexity of the responses through the involvement of different mechanisms.
Strategies to Prevent Biofilm Infections on Biomaterials: Effect of Novel Naturally-Derived Biofilm Inhibitors on a Competitive Colonization Model of Titanium by Staphylococcus aureus and SaOS-2 Cells
Authors: Reigada Inés , Pérez-Tanoira Ramón , Patel Jayendra Z. , Savijoki Kirsi , Yli-Kauhaluoma Jari , Kinnari Teemu J. , Fallarero Adyary
Published: March 2020

Biofilm-mediated infection is a major cause of bone prosthesis failure. The lack of molecules able to act in biofilms has driven research aimed at identifying new anti-biofilm agents via chemical screens. However, to be able to accommodate a large number of compounds, the testing conditions of these screenings end up being typically far from the clinical scenario. In this study, we assess the potential applicability of three previously discovered anti-biofilm compounds to be part of implanted medical devices by testing them on in vitro systems that more closely resemble the clinical scenario. To that end, we used a competition model based on the co-culture of SaOS-2 mammalian cells and Staphylococcus aureus (collection and clinical strains) on a titanium surface, as well as titanium pre-conditioned with high serum protein concentration. Additionally, we studied whether these compounds enhance the previously proven protective effect of pre-incubating titanium with SaOS-2 cells. Out of the three, DHA1 was the one with the highest potential, showing a preventive effect on bacterial adherence in all tested conditions, making it the most promising agent for incorporation into bone implants. This study emphasizes and demonstrates the importance of using meaningful experimental models, where potential antimicrobials ought to be tested for the protection of biomaterials in translational applications.
Classical Microbiological Diagnostics of Bacteremia: Are the Negative Results Really Negative? What is the Laboratory Result Telling Us About the “Gold Standard”?
Authors: Źródłowski Tomasz , Sobońska Joanna , Salamon Dominika , McFarlane Isabel M. , Ziętkiewicz Mirosław , Gosiewski Tomasz
Published: March 2020

Standard blood cultures require at least 24–120 h to be reported as preliminary positive. The objective of this study was to compare the reliability of Gram staining and fluorescent in-situ hybridization (FISH) for detecting bacteria in otherwise negative blood culture bottles. Ninety-six sets were taken from patients with a diagnosis of sepsis. Six incomplete blood culture sets and eight blood cultures sets demonstrating positive growth were excluded. We performed Gram stain and FISH on 82 sets taken from post-operative septic patients: 82 negative aerobic blood cultures, 82 anaerobic blood cultures, and 82 blood samples, as well as 57 blood samples taken from healthy volunteers. From the eighty-two blood sets analyzed from the septic patients, Gram stain visualized bacteria in 62.2% of blood samples, 35.4% of the negative aerobic bottles, and in 31.7% of the negative anaerobic bottles. Utilizing FISH, we detected bacteria in 75.6%, 56.1%, and 64.6% respectively. Among the blood samples from healthy volunteers, FISH detected bacteria in 64.9%, while Gram stain detected bacteria in only 38.6%. The time needed to obtain the study results using Gram stain was 1 h, for FISH 4 h, and for the culture method, considering the duration of growth, 5 days. Gram stain and FISH allow quick detection of bacteria in the blood taken directly from a patient. Finding phagocytosed bacteria, which were also detected among healthy individuals, confirms the hypothesis that blood microbiome exists.