Publications by authors named "Martel Richard"

Polymer solution injection has emerged as a promising method for the remediation of NAPL (non-aqueous phase liquids)-contaminated aquifers. This technique enhances recovery efficiency by modifying viscous forces, stabilizing the displacement front, and minimizing channeling effects. However, there remains a significant gap in understanding the behavior of polymer solutions, particularly those with different molecular weights (MW), for mobilizing DNAPL (dense non-aqueous phase liquids) trapped in heterogeneous aquifers, especially within low-permeability layers.

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Background: Congenital diaphragmatic hernia (CDH) survivors exhibit an increased risk for developing musculoskeletal anomalies. This prospective long-term cohort study investigates the characteristics, predictors and dynamic changes of different chest wall deformities in a large cohort of CDH patients.

Methods: All children diagnosed with CDH and treated at the University Hospital Mannheim from 2010 to 2023 were included.

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Introduction:  Interferential current (IFC) has been studied in several clinical trials for the treatment of bowel motility disorders, most often in children. However, only moderate effects are reported, and in contrast to IFC, the so-called placebo application is indiscernible. The mechanisms and neuroanatomic points of action remain elusive.

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Article Synopsis
  • The demand for unconventional crude oils has led to increased production and transportation of diluted bitumen (dilbit) in Western Canada, but there's limited understanding of how spilled dilbit affects shallow groundwater systems.
  • Experiments showed that dilbit spills result in higher concentrations and faster transport rates of harmful compounds (like BTEX and PACs) compared to spills of conventional heavy crude oil.
  • Toxic effects were observed in fish larvae exposed to contaminated water, indicating that both oil types pose risks, potentially due to unknown toxic substances that can be transported in soil following spills.
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Recent advancements in materials science have shed light on the potential of exploring hierarchical assemblies of molecules on surfaces, driven by both fundamental and applicative challenges. This field encompasses diverse areas including molecular storage, drug delivery, catalysis, and nanoscale chemical reactions. In this context, the utilization of nanotube templates (NTs) has emerged as promising platforms for achieving advanced one-dimensional (1D) molecular assemblies.

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Introduction:  Abdominal adhesions following surgery can lead to complications like intestinal obstruction and pelvic pain. While no molecular therapies currently target the underlying adhesion formation process, various barrier agents exist. 4DryField® has shown promise in reducing bleeding and adhesions in adults.

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Chemical vapour deposition (CVD) synthesis of graphene on copper has been broadly adopted since the first demonstration of this process. However, widespread use of CVD-grown graphene for basic science and applications has been hindered by challenges with reproducibility and quality. Here we identify trace oxygen as a key factor determining the growth trajectory and quality for graphene grown by low-pressure CVD.

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Cell replacement in aganglionic intestines is a promising, yet merely experimental tool for the therapy of congenital dysganglionosis of the enteric nervous system like Hirschsprung disease. While the injection of single cells or neurospheres to a defined and very restricted location is trivial, the translation to the clinical application, where large aganglionic or hypoganglionic areas need to be colonized (hundreds of square centimetres), afford a homogeneous distribution of multiple neurospheres all over the affected tissue areas. Reaching the entire aganglionic area is critical for the restoration of peristaltic function.

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Pain sensitivity of healthy subjects in the cold-pressor (CP) test was proposed to be dichotomously distributed and to represent a pain sensitivity trait. Still, it has not been systematically explored which factors influence this pain sensitivity readout. The aim of this study was to distinguish potential contributions of local tissue-related factors such as perfusion and thermoregulation or gain settings in nociceptive systems.

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Background: The purpose of this report is to describe the seminal case of a near-term human fetus with a life-threatening left diaphragmatic hernia that underwent fetoscopic tracheal occlusion (FETO) combined with fetoscopic partial removal of herniated bowel from the fetal chest by fetoscopic laparoschisis (FETO-LAP).

Case Summary: A life-threatening left diaphragmatic hernia (liver-up; o/e LHR of ≤25%; MRI lung volume ≤ 20%) was observed in a human fetus at 34 weeks of gestation. After counselling the mother about the high risks of postnatal demise if left untreated, the expected limitations of fetoscopic tracheal occlusion (FETO), and the previously untested option of combining FETO with fetoscopic laparoschisis, i.

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Article Synopsis
  • A diesel spill in Québec during the late 1980s led to ongoing groundwater contamination, despite remediation efforts that reduced much of the pollution.
  • Recent unconfirmed leaks from industrial activities may also be affecting local water quality, particularly with elevated levels of polycyclic aromatic compounds (PACs).
  • Analysis of stable carbon isotope ratios in groundwater showed that contamination primarily stems from the historical diesel spill, rather than from asphalt or fuel oil sources nearby.
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As an efficient method to remove contaminants from highly polluted sites, enzyme biodegradation addresses unresolved issues such as bioremediation inefficiency. In this study, the key enzymes involved in PAH degradation were brought together from different arctic strains for the biodegradation of highly contaminated soil. These enzymes were produced via a multi-culture of psychrophilic Pseudomonas and Rhodococcus strains.

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Despite recent attention being paid to the biodegradation of petroleum hydrocarbons in cold environments, scale-up studies of biodegradation are lacking. Herein, the effect of scale-up on the enzymatic biodegradation of highly contaminated soil at low temperatures was studied. A novel cold-adapted bacteria (Arthrobacter sp.

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We designed, synthesized, and characterized a Raman nanoprobe made of dye-sensitized single-walled carbon nanotubes (SWCNTs) that can selectively target biomarkers of breast cancer cells. The nanoprobe is composed of Raman-active dyes encapsulated inside a SWCNT, whose surface is covalently grafted with poly(ethylene glycol) (PEG) at a density of ∼0.7% per carbon.

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The oil sands region in Western Canada is one of the world's largest proven oil reserves. To facilitate pipeline transport, highly viscous oil sands bitumen is blended with lighter hydrocarbon fractions to produce diluted bitumen (dilbit). Anticipated increases in dilbit production and transport raise the risk of inland spills.

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A pilot field study was conducted in a Canadian northern village (NV) to assess the remediation efficiency of sodium persulphate (SPS) alkali activated with calcium peroxide (CP) to degrade diesel from Arctic raft soil. A minimum temperature increase in the subsurface due to overall process reactions was required. The projected context of application was imperative to preserve the integrity of the remaining permafrost.

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A bioinspired device was fabricated as a sustainable remedial method and its performance as a membrane-enzyme reactor with cyclic ultrafiltration was investigated. The body of the jellyfish-like device was composed of two parts: 1) Jellyfish arms: Mono and co-axial electrospinning have been utilized to synthesize the flexible parts (e.g.

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The use of surfactant foam for the remediation of diesel fuel, a Light Non-Aqueous Phase Liquid (LNAPL), was investigated in sand column experiments using X-ray Computed Tomography (CT). A preliminary series of tests were carried out on six surfactant candidates in order to measure their physical properties, including critical micelle concentrations and interfacial tensions (IFT) with the LNAPL. Batch tests for foam stability were carried out with and without added LNAPL, in order to measure the half-life of foam columns produced with each surfactant candidate.

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As graphene field-effect transistors (GFETs) are becoming increasingly valued for sensor applications, efficiency and control of their surface functionalization become critical. Here, we introduce an innovative method using a gate electrode to precisely modulate aryldiazonium functionalization directly on graphene devices. Although this covalent chemistry is well-known, we show that its spontaneous reaction on GFETs is highly heterogeneous with a low overall yield.

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Black phosphorus (BP) is unique among layered materials because of its homonuclear lattice and strong structural anisotropy. While recent investigations on few-layer BP have extensively explored the in-plane (, ) anisotropy, much less attention has been given to the out-of-plane direction (). Here, the optical response from bulk BP is probed using polarization-resolved photoluminescence (PL), photoluminescence excitation (PLE), and resonant Raman scattering along the zigzag, out-of-plane, and armchair directions.

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Modern societies are generating considerable volume of Construction and Demolition Wastes (C&DW) annually. Most recycling facilities offers viable sorting and recycling options for the coarser particles of the different materials found in those wastes. However, usual dry mechanical sorting and human sorting are not efficient on C&DW fines particles (C&DF, <10 mm) representing the third of the C&DW produced and being composed of similar materials.

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p-Xylene is considered a recalcitrant compound despite showing a similar aromatic structure to other BTEXs (benzene, toluene, ethylbenzene, xylene isomers). This study evaluated the p-xylene biodegradation potential of three psychrophilic Pseudomonas strains (Pseudomonas putida S2TR-01, Pseudomonas synxantha S2TR-20, and Pseudomonas azotoformans S2TR-09). The p-xylene metabolism-related catabolic genes (xylM, xylA, and xylE) and the corresponding regulatory genes (xylR and xylS) of the selected strains were investigated.

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Though many studies pertaining to soil bioremediation have been performed to study the microbial kinetics in shake flasks, the process efficiency in column tests is seldom. In the present study, soil columns tests were carried out to study the biodegradation of soil contaminated with a high concentration of diesel (≈19.5 g/kg) petroleum hydrocarbons expressed as C-C.

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Enzymatic bioremediation is a sustainable and environment-friendly method for the clean-up of contaminated soil and water. In the present study, enzymatic bioremediation was designed using cold-active enzymes (psychrozymes) which catalyze oxidation steps of p-xylene biodegradation in highly contaminated soil (initial concentration of 13,000 mg/kg). The enzymes were obtained via co-culture of two psychrophilic Pseudomonas strains and characterized by kinetic studies and tandem LC-MS/MS.

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Toluene/o-Xylene Monooxygenase (ToMO) is equipped with a broad spectrum of aromatic substrate specificity (such as BTEX; benzene, toluene, ethylbenzene, and isomers of xylenes). TOMO has can hydroxylate more than a single position of aromatic rings in two consecutive monooxygenation reactions. Catechol 1,2-dioxygenase (C1,2D) is an iron-containing enzyme able to cleave the ring of catechol (the converted product from ToMO) for complete detoxification of BTEX.

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