Search

Nitrogen use in agriculture often prioritizes immediate yield gains at the expense of the environment and agroecosystem health. This problem persists because current solutions for crop nitrogen use inefficiency focus too narrowly on inputs and overlook the internal processes that govern nitrogen’s fate, from crop uptake and environmental losses to storage and transfer between various organic pools. We synthesize recent research developments in soil nitrogen biogeochemistry into an aspirational and accessible microbe-centered framework that clarifies understanding of nitrogen accumulation, recycling, and plant uptake processes in soil. This framework can guide scientific exploration and practical applications to boost crop yields, enrich soil organic matter, and reduce environmental nitrogen losses.

The expansion of agroforestry could provide substantial climate change mitigation (up to 0.31 Pg C yr−1), comparable to other prominent natural climate solutions such as reforestation. Yet, climate-focused agroforestry efforts grapple with ambiguity about which agroforestry actions provide mitigation, uncertainty about the magnitude of that mitigation and inability to reliably track progress. In this Perspective, we define agroforestry as a natural climate solution, discuss current understanding of the controls on farm-scale mitigation potential and highlight recent innovation on emergent, high-resolution remote sensing methods to enable detection, measurement and monitoring. We also assess the status of agroforestry in the context of global climate ambitions, highlighting regions of underappreciated expansion opportunity and identifying priorities for policy and praxis.

•Microcolumns with removable capillary junctions were coated for space exploration.•The manifold and connections were optimized to limit extra-column volumes.•Column efficiency was increased by 100 % using a reduced coating velocity.•The best microcolumn efficiency was >45,000 theoretical plates.•Coating efficiencies of square cross-section and cylindrical columns were compared.

To satisfy the global demand, more and more high-quality fuels, pure or converted from heavy oil cuts, like vacuum gas oil (VGO), into highly refined fuels are needed. To meet this increasingly demand, molecular information is mandatory to allow for a detailed characterization of these heavy oil fractions. Several separation techniques have been developed in the last years, among them gas chromatography (GC) and GC × GC are the most widely used ones for obtaining this information. To perform an exhaustive gas chromatographic analysis, all steps must be optimized. In particular, the injection process, which is a key part of the chromatographic process, should ensure the transfer of a representative part of the sample into the columns. This paper will show how the optimization of all programmable-temperature vaporizing (PTV) injection parameters allowed the determination of optimal high-temperature GC × GC (HT-GC × GC) conditions for the analysis of vacuum gas oil avoiding sample discrimination and sample degradation. n-Paraffins recovery from nC8to nC44was satisfactory and was calculated to be between 93.0 and 100.5% using PTV in splitless injection mode, and between 86.8 and 100.1% in solvent vent mode. A first application of HT-GC × GC using a flow modulator for the analysis of one of the heaviest petroleum cuts is also described. Comparison with other injection techniques showed the possibility to implement PTV, compared to on-column injector, in high-temperature applications for allowing satisfactory recovery of whole sample.

A method utilizing turbulent flow to perform ultrafast separations and screen chiral compounds in supercritical fluid chromatography (SFC) is described. Carbon dioxide at high flow rates (up to 4.0 mL/min) is delivered into gas chromatography (GC) open-tubular columns (OTC, 0.18 mm i.d., 20 m long, ∼0.2 μm stationary film thickness) to establish turbulent flow at Reynolds numbers (Re) as high as 9000. Postcolumn dispersion is eliminated by using a modified UV detector that takes measurements directly on column. Upon crossing the laminar-to-turbulent flow transition regime, a significant reduction in plate height is observed resulting in a nearly 3-fold increase in peak capacity from the laminar regime. This is explained by the massive reduction of the mass transfer resistance in the mobile phase due to a flatter flow profile and faster analyte dispersion across the open-tubular column (OTC) i.d.. Demonstrated in this work is a 9 s separation of four polycyclic aromatic hydrocarbons (PAHs) over a 2.2 s separation window using a poly(dimethylsiloxane-co-methylphenylsiloxane) coated OTC. Additionally, three chiral compounds and three chiral cyclodextrin-incorporated OTCs were evaluated at high temperatures (90–120 °C) and CO2flow rates (3.3–3.7 mL/min) to demonstrate column stability and application of this method for rapid screening. Turbulent SFC provides a separation method for users desiring to achieve separation speeds above what is currently available with very high-pressure LC systems and do so without the resolution loss commonly observed at maximum allowable speed.

Temperature-cycle-induced deracemization (TCID) has been widely studied in the field of chiral separation, ranging from fundamental research to applications. In this study, the second-order asymmetric transformation (SOAT) of 2-methoxy-1-naphthamide in an azeotropic mixture of ethyl acetate and cyclohexane is compared with TCID, in terms of process productivity. The results indicate that the volumetric productivity using SOAT was over 100-times higher than that using TCID, such that a scale-up by a factor of 10 was easily implemented.

Herein, we report the chiral symmetry breaking of 2-methoxy-1-naphthamide atropisomers through temperature cycling without the use of any racemization reagent. The racemization rate (k1) controls the deracemization process when the cooling of the slurry is slow enough to keep the system close to equilibrium. The productivity appears proportional to the racemization rate (k1) multiplied by the solubility.

•Inhalation of pharmaceuticals is a promising alternative.•Protein atomization process in presence of mannitol or trehalose provide suitable particles for inhalation.•IgG co spray-dried with trehalose gives an alloy of IgG/trehalose that confers a good stability of the IgG.•Trehalose has a protective role during the spray drying process.

Due to their easy functionalization and their unique conformational and recognition properties, calixarenes are attracting molecular platforms for the elaboration of separation systems. Thus, in the last decades, these macrocyclic compounds have been subject to extensive research in analytical chemistry. This review is focused on the use of calixarenes as selectors in the chromatographic separation field. The structures of calixarene derivatives and their applications as stationary phases for gas chromatography as well as high-performance liquid chromatography are described.

Dans une démarche qui vise à uniformiser les procédures de greffe de cellules souches hématopoïétiques, la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC) a organisé les septièmes Ateliers d’harmonisation des pratiques en allogreffe en septembre 2016 à Lille. Le but de ces ateliers annuels est de trouver un terrain d’entente entre des centres qui le souhaitent dans les domaines où la littérature ne fournit pas de réponses incontestables et consensuelles. Dans cet atelier, nous élaborons le carnet national destiné aux patients autogreffés.

Crosslinked carboxymethylpullulan have been synthesized by using the dibromohexan as a crosslinking agent. Two phases are obtained after synthesis: a gel and a sol fraction. The sol/gel ratio is dependent on the variation of the polymer concentration (Cp), the incorporation ratio of the dibromohexan (Rc) and the average molar mass (Mn). The study of the swelling degree in water of the gel fraction has shown that this phase is not stable and that it shrinks after a certain time. This phenomenon is accelerated by an increase in temperature. At a macroscopic level, the gelation point is not reached. Nevertheless, the quantity of dibromohexan incorporated seems to be sufficient to obtain a gel.

The static headspace technique is the most common approach to residual solvent analysis in pharmaceutical and environmental matrices. This paper presents an alternative tool where the volatile impurities are released from the matrix by working directly on a small amount of sample at a high equilibration temperature: the so‐called Full Evaporation Technique (FET). The capability of this method was evaluated on a mixture of nine solvents, which belong to Class 3 in the classification of the European Pharmacopoeia Agency for residual solvents, at various levels of concentration: ethanol, acetone, 2‐propanol, methyl acetate, 2‐butanone, ethyl acetate, tetrahydrofuran, 2‐methyl‐1‐propanol, 1‐butanol. Data on linearity, accuracy, precision and sensitivity are reported. Use of an internal standard proved to be necessary when using such a method. The method is then successfully applied to the analysis of solvent traces in permethylated β‐cyclodextrin.

Although the title compound crystallizes as a stable conglomerate without any detectable solid solution, particles in the shape of single crystals grown from the racemic aqueous solution without stirring contain almost no enantiomeric excess. From stereoselective dissolution experiments carried out in a solution saturated with a single enantiomer, it is shown that the formation of these particles results from the epitaxial association of macroscopic homochiral lamellar fragments parallel to the {101} faces. This alternated 2D nucleation and growth process is shown to constitute an oscillating crystallization mechanism controlled by diffusion only. This is confirmed by the implementation of a gentle stirring of the mother liquor during the crystallization which led to crystals having a high enantiomeric excess. Molecular modeling investigations indicate that the epitaxial region can be described at a molecular level. The structure of two racemic compounds could be generated from this epitaxial zone.

The present study investigated the use of a dedicated gas chromatography (GC) column (L= 70 cm, 75 μm deep, and 6.195 mm wide) with radially elongated pillars (REPs) as the second column in a comprehensive two-dimensional gas chromatography (GC × μGC) system. Three stationary phases [apolar polydimethylsiloxane (PDMS), medium polar room-temperature ionic liquid (RTIL) based on monocationic phosphonium, and polar polyethylene glycol (PEG-1000)] have been coated using the static method at constant pressure or using an original vacuum pressure program (VPP) from 400 to 4 mbar. The best efficiency reached up to N= 62,000 theoretical plates for a film thickness of 47 nm at 100 °C for an iso-octane peak (k= 0.16) at an optimal flow rate of 4.8 mL/min. The use of the VPP improved the efficiency by approximately 15%. Efficiencies up to 28,000 and 47,000 were obtained for PEG-1000 and RTIL, respectively. A temperature-programmed separation of a mixture of 11 volatile compounds on a PDMS-coated chip was obtained in less than 36 s. The PDMS-, PEG-1000-, and RTIL-coated chips were tested as the second column using a microfluidic reverse fill/flush flow modulator in a GC × μGC system. The REP columns were highly compatible with the operating conditions in terms of flow rate and with more than 30,000 plates for the iso-octane peak. Moreover, a commercial solvent called white spiritcontaining alkanes and aromatic compounds was injected in three sets of columns in normal and reverse modes, demonstrating the great potential of the chip as a second-dimension separation column.

•SOC stock prediction was accurate using VNIR spectra of sieved dried samples•Prediction in stone-free soils was more accurate with laboratory than field spectra•Calibration by spectral neighbors was recommended when using a large library•There was no evidence of indirect VNIRS prediction of SOC stock

Cancer Cachexia is a metabolic syndrome that can be present even in absence of weight loss and associated with significantly impaired survival. Muscle wasting represents a key-symptom of this syndrome and we recently demonstrated the strong prognosis impact of sarcopenia assessed by computed tomography (CT)-scan in diffuse large B-cell lymphoma (DLBCL) (Lanic et al. Leukemia & Lymphoma 2013). Conversely, the clinical relevance of loss of fat mass (adipopenia) remains unclear. The aim of this study was (i) to investigate the prognostic impact of a multidimensional tool combining a nutritional parameter (albuminemia) and body composition measurements (skeletal muscle and body fat composition) in elderly patients with DLBCL treated by chemotherapy and rituximab (R) (ii) to document the evolution of sarcopenia after immunochemotherapy.

Cancer Cachexia is a metabolic syndrome that can be present even in absence of weight loss and associated with significantly impaired survival. Muscle wasting represents a key-symptom of this syndrome and we recently demonstrated the strong prognosis impact of sarcopenia assessed by computed tomography (CT)-scan in diffuse large B-cell lymphoma (DLBCL) (Lanic et al. Leukemia & Lymphoma 2013). Conversely, the clinical relevance of loss of fat mass (adipopenia) remains unclear. The aim of this study was (i) to investigate the prognostic impact of a multidimensional tool combining a nutritional parameter (albuminemia) and body composition measurements (skeletal muscle and body fat composition) in elderly patients with DLBCL treated by chemotherapy and rituximab (R) (ii) to document the evolution of sarcopenia after immunochemotherapy.This retrospective analysis included 80 DLBCL patients older than 70 years (y) and treated by R-CHOP or R-miniCHOP. Skeletal muscle (SM), visceral (V) and subcutaneal (S) adipose (A) tissues were measured by analysis of stored CT images at the Lumbar vertebrae 3 (L3) level. The surface of the muscular and adipose tissues was selected according to CT Hounsfield unit. Values were normalized for stature to calculate the L3 SM index (LSMI, in cm2/m2), the LVAI and the LSAI and used to define sarcopenia and visceral/subcutaneal adipopenia.The characteristics of the patients were as follows: median age = 78 y [70-95]; 36 males; IPI 0-2 = 22, 3-5 = 58; treatment by R-CHOP (n = 45) or R-miniCHOP (n = 35); median body mass index (BMI; in kg/m2) = 23.9. According to the sex-specific defined cut-offs for LSMI (< 55.8 cm²/m² for men and 38.9 cm²/m² for women), 44 DLBCL patients (55 %, 23 males) were considered as sarcopenic. With a median follow-up of 39 months, the 2y overall survival (OS) in the sarcopenic population was 46% as compared to 84% in the non-sarcopenic group (HR = 3.12; CI95%, 1.66-5.88; p=0.0004). The median LSAI was 76.3 cm2/m2 [10-167] in females and 47.4 cm2/m2[22-100] in males. The median LVSAI was 43.5 cm2/m2[3-141] in females and 50.4 cm2/m2[14-159] in males. Adipopenia, defined by a low LVAI and/or a low LSAI was also highly predictive of the outcome. The 2y OS of the low LVAI population was 48% as compared to 82% for the non-adipopenic group (HR = 2.20; CI95%, 1.19-4.05; p=0.01). The 2y OS in the low LSAI population was 48% as compared to 80% in the non-adipopenic group (HR = 2.28; CI95%, 1.23-4.21; p=0.008). A Three-point cachexia score (CS) including adipopenia, sarcopenia and hypo-albuminemia (defined by an albuminemia < 35 g/L) was build and delineates three distinct risk-groups (Figure 1). More importantly the CS remains predictive of the prognosis in a multivariate analysis including BMI (< or >= 25 kg/m2), age (< or >= 80y), IPI and gender (HR=2.5; CI95%= 1.14-5.39; p =0.02). LMSI was subsequently reassessed in thirty seven patients during the routine CT scan follow-up [mean = 10 months after pre-treatment CT scan (range 2.8-19.2)]. 15 (40%) patients displayed a 5% decrease of their LSMI, whereas 13 (35%) and 9 (25%) displayed no significant change or increase (>5%) of the LMSI respectively.Our study demonstrates that sarcopenia and adipopenia estimated by CT-scan define cachexia more accurately than BMI or weight loss in elderly DLBCL patients. These factors can be integrated in a cachexia scoring tool which predicts the outcome independently of the BMI and of the IPI. CT scan follow-up indicates that cachexia is a reversible process that should be integrated as part of the therapeutic target in combination with lymphoma treatment. A prospective multicentric trial (registered as NCT01715961/Clinical.gov) is ongoing to validate these anthropometric and nutritional parameters and compare to geriatric assessment scales.No relevant conflicts of interest to declare.